CN1697356B - Preamble formats of mimo wireless communication system - Google Patents

Abstract

The invention discloses a method of generating preamble information of a frame in a Multiple Input Multiple Output (MIMO) wireless communication system. The method begins by generating a carrier sense field for each transmit antenna of a MIMO wireless communication system, which is cyclically shifted. The method continues to transmit the first group of antennas to the MIMO wireless communication system: generate the first guard interval after the carrier field; generate at least one channel sounding field, and at this time at least one channel sounding field is cyclically shifted from the transmitting antenna to the transmitting antenna, and There is at least one channel sounding field after the first guard interval. When the MIMO wireless communication system includes more than one set of transmit antennas, for another set of transmit antennas: at least one other channel sounding field is generated, and in the other set, at least one channel sounding field is cyclically shifted from transmit antenna to transmit antenna , wherein at least one channel sounding field is followed by at least another channel sounding field; the first guard interval is generated before another channel sounding field is generated.

Description

Preamble Information Format of Multiple-Input Multiple-Output Wireless Communication System

technical field

The present invention generally relates to a wireless communication system, and more particularly relates to a wireless communication protocol supporting multiple input and multiple output in a wireless local area network.

Background technique

Existing communication systems support wireless and wired communication between wireless communication devices and wired communication devices. Such communication systems are used in domestic and international communication between cellular phone communication systems and the Internet, and are also used in indoor "point-to-point" point" wireless network. Any kind of communication system must be established according to one or more communication standards and operate accordingly. For example, a wireless communication system may operate according to one or more of the following standards (including but not limited to): IEEE802.11, Bluetooth, Advanced Mobile Phone Service (AMPS), Digital Advanced Mobile Phone Service (DAMPS), Global Mobile Communication system (GSM), code division multiple access (CDMA), local multipoint distribution service (LMDS), multi-channel multipoint distribution technology (MMDS) and technologies derived from the above several technologies.

Due to different wireless communication systems, a wireless communication device can directly or indirectly establish communication with another wireless communication device. Wireless communication equipment includes: cellular phone, wireless walkie-talkie, personal digital assistant (PDA), personal computer (PC), notebook computer and home entertainment equipment, etc. For direct communication (also known as "point-to-point" communication), adjust the receiver and transmitter of the participating wireless communication equipment to the same channel or channel group, and you can pass these channels or channel groups (for example, wireless communication system One of a plurality of radio frequency carrier waves) to communicate. For indirect wireless communication, any wireless communication device either directly contacts a base station (such as a cellular base station) in a plurality of interconnected base stations through a designated channel, or directly contacts a base station in a plurality of interconnected access points. An access point (such as a wireless network indoors or in a building) is connected, and the interconnected base station and the interconnected access point communicate directly to complete the communication connection between wireless devices. Communications between interconnected base stations and interconnected access points are accomplished through system controllers, the public telephone network, the Internet, and other wide area networks.

Each wireless communication device participating in wireless communication either has a combined wireless transceiver (that is, has a receiver and a transmitter) or is connected to an associated wireless transceiver (for example, an indoor or in-building wireless Base stations of communication networks, radio frequency modems, etc.). The transmitter includes: a data modulation section, one or more intermediate frequency sections, and a power amplifier. The data modulation part converts the original data into a baseband signal according to a specific wireless communication standard. One or more intermediate frequency parts mix the baseband signal with one or more local oscillators to synthesize a radio frequency signal. The power amplifier amplifies the radio frequency signal and transmits it from the antenna. go out.

As we all know, the receiver needs to be connected to the transmitting antenna. The receiver includes: a low noise amplifier, one or more intermediate frequency sections, a filtering section and a data recovery section. The low noise amplifier receives the incoming RF signal from the antenna and amplifies the signal. One or more intermediate frequency sections mix the amplified radio frequency signal with one or more local oscillators, and the amplified radio frequency signal is converted into a baseband signal or an intermediate frequency signal. The filtering part filters the baseband signal or the intermediate frequency signal to attenuate the signal outside the unnecessary band, so as to obtain the filtered signal. The data restoration part restores the filtered signal to original data according to a specific wireless communication standard.

Furthermore, even in the same wireless communication system, the standards adopted by wireless devices may be different. For example, the 802.11 standard has evolved from IEEE 802.11 to IEEE 802.11b, then to IEEE 802.11a, and then to IEEE 802.11g. In the same wireless local area network, wireless communication equipment adopting IEEE 802.11b standard can coexist with wireless communication equipment adopting IEEE 802.11g standard. Another example is that in the same wireless local area network, a wireless communication device adopting the IEEE 802.11a standard can coexist with a wireless communication device adopting the IEEE 802.11g standard. When the original device (that is, the device using the earlier version of the same standard) and the device using the later version of the standard coexist in the same wireless local area network, in order to avoid conflicts, people use a method that allows the original device to recognize the new version. Whether the device is using the wireless channel mechanism.

For example, backward compatibility with legacy equipment has been specifically designed for both the physical (PHY) layer (in the case of IEEE 802.11b) and the media storage control (MAC) layer (in the case of IEEE 802.11g) activation. The backward compatibility of the physical layer is realized by reusing the preamble information of the physical layer of the earlier standard. In this case, even if the original device cannot completely demodulate and decode the transmitted frame, it still needs to decode all the preamble information, and such decoding can provide sufficient information to determine whether the wireless channel is in use at a specific time period.

In the medium storage control layer, the compatibility with the original equipment can be achieved by adopting the method of transmitting a special frame by the equipment of the new standard. This special frame uses the mode and data rate used by the original equipment. For example, new devices transmit clear-to-send/ready-to-send (CTS/RTS) exchange frames, as well as clear-to-send frames, as adopted in IEEE 802.11g. These special frames contain information to set the Network Allocation Vector (NAV) of legacy devices so that they can identify whether a wireless channel is occupied by a newer base station.

However, the existing two mechanisms do not perform as expected because they are not backward compatible and are independent of each other.

Therefore, there is a need for a method and apparatus for supporting multi-user protocols in a wireless communication system, including a wireless local area network.

Contents of the invention

The preamble information format of the MIMO wireless communication system of the present invention fully satisfies this requirement and some other requirements. In one example, the method for generating preamble information of a MIMO wireless communication system frame is performed in the following manner: first, each antenna of the MIMO wireless communication generates a carrier detection field, and then the carrier detection field is transmitted from a The antenna is cyclically shifted to another transmit antenna; then, the first group of transmit antennas in the MIMO wireless communication system generates a guard interval after the carrier detection field, followed by at least one channel detection field, wherein the generated At least one channel sounding field is cyclically shifted from one antenna of the first set of antennas to another antenna immediately following the first swap interval. Secondly, if the MIMO wireless communication system includes more transmitting antennas than the first group of antennas, another group of antennas performs the following work: generating another at least one channel sounding field, wherein the generated another at least one channel sounding The field is cyclically shifted from one antenna of the other set of antennas to the other antenna following the first at least one channel sounding field; and before the other at least one channel sounding field, a first guard interval is generated.

In another example, the method for generating the preamble information compatible with the original version of the MIMO wireless communication system frame is performed in the following manner: first, each of the multiple transmit antennas in the MIMO wireless communication system Antennas generate a carrier detect field, where the carrier detect field is cyclically shifted from one transmit antenna to the other; secondly, the first of the multiple antennas does the following: generates the first guard interval; the first channel sounding field is generated after the first guard interval; the second channel sounding field is generated after the first channel sounding field; again, in the first group of multiple transmit antennas, each of the remaining antennas The following work is done: generating a third channel sounding field; generating a fourth channel sounding field after the third channel sounding field; and generating a second guard interval before the third channel sounding field.

According to one aspect of the present invention, a method for generating preamble information of a frame for a multiple-input multiple-output wireless communication system is provided, and the method includes the following parts:

For each transmit antenna in the multiple-input multiple-output wireless communication system: generating a carrier detect field, wherein the carrier detect field is cyclically shifted from one transmit antenna to another transmit antenna;

The first group of transmitting antennas in the multiple-input multiple-output wireless communication system: generate a first guard interval after the carrier detection field; generate at least one channel sounding field, wherein the at least one channel sounding field is followed by the first guard interval Cyclic shifting from one of the antennas in the first group to the other;

When the multiple-input multiple-output wireless communication system has no more than one set of transmit antennas, another set of transmit antennas: generates another at least one channel sounding field, wherein the other at least one channel sounding field is followed by another at least one channel the sounding field is cyclically shifted from one of the other set of antennas to another; and before another at least one channel sounding field, a first guard interval is generated;

Preferably, for each transmitting antenna in the first group of transmitting antennas in the multiple-input multiple-output wireless communication system, the method further includes:

generating a second guard interval after another at least one channel sounding field; and

Generate a channel sounding field after the second guard interval;

Preferably, for each transmitting antenna in another group of antennas of the multiple-input multiple-output wireless communication system, the method further includes:

A third guard interval is generated before the at least one other channel sounding field, wherein the duration of the first and third guard intervals is longer than that of the second guard interval.

Preferably, the generated carrier detection field consists of the following parts:

A short training sequence is generated according to the original protocol, wherein the cyclic shift is based on multiple transmit antennas and the continuation of the short training sequence.

Preferably, if the number of transmitting antennas is 3, the method further includes:

For the first group of transmitting antennas of the MIMO wireless communication system, it generates the first and second long training sequences according to the original protocol in at least one channel sounding field, wherein the first group of transmitting antennas includes three two of the transmit antennas, wherein the first and second long training sequences are cyclically shifted, respectively; and

Generating a third long training sequence according to the original protocol, which is regarded as another at least one channel sounding field of another set of transmit antennas; wherein the other set of antennas includes the third of the three transmit antennas;

Preferably, if the number of transmitting antennas is 4, the method further includes:

For the first group of transmit antennas of the MIMO wireless communication system, the first and second long training sequences are generated according to the original protocol, which are regarded as at least one channel sounding field; wherein, the first group of antennas contains four two of the transmit antennas, and the first and second long training sequences are cyclically shifted respectively; and

Another group of antennas generates the third and fourth long training sequences according to the original protocol, which are regarded as another at least one channel sounding field of another group of transmitting antennas; wherein, the other group of antennas includes four transmitting antennas The other two, and the third and fourth long training sequences are cyclically shifted respectively;

Preferably, for each transmit antenna in the multiple-input multiple-output wireless communication system, the method includes:

generating another guard interval immediately after another at least one channel sounding field;

generating a second channel sounding field immediately after the further guard interval;

According to one aspect of the present invention, it provides a method for generating a preamble information of a frame compatible with the original version for an MIMO wireless communication system frame, and the method includes the following parts:

Each transmit antenna of the plurality of antennas of the multiple-input multiple-output wireless communication system generates a carrier detect field, wherein the carrier detect field is cyclically shifted from one transmit antenna to another transmit antenna;

For the first of multiple transmit antennas:

The first guard interval is generated immediately after the carrier detection field;

Immediately following the first guard interval, the first channel sounding field is generated;

Immediately following the first channel sounding field, a second channel sounding field is generated;

For each transmit antenna in the first group of the remaining transmit antennas of the plurality of antennas:

generate a third channel sounding field;

Immediately following the third channel sounding field, a fourth channel sounding field is generated;

And generate the second guard interval before generating the third channel sounding field;

Preferably, the plurality of transmission antennas includes three transmission antennas: the third and fourth channel sounding fields in the first group of transmission antennas are respectively cyclically shifted from one transmission antenna to another transmission antenna;

Preferably, the plurality of transmit antennas includes four transmit antennas:

For the fourth antenna of the multiple antennas:

generate a fifth channel sounding field;

Immediately following the fifth channel sounding field, a sixth channel sounding field is generated;

Generate a third guard interval before generating the fifth channel sounding field;

Preferably, for each transmit antenna in the plurality of transmit antennas, the method further includes:

Another guard interval is generated immediately after the sixth channel sounding field;

A channel sounding field is generated immediately after the second guard interval;

Preferably, for the first transmitting antenna, the method further includes:

Immediately following the second channel sounding field produces another guard interval;

Immediately following the second guard interval, a channel sounding field is generated;

Preferably, the generated carrier detection field consists of the following parts:

A short training sequence is generated according to the original protocol, wherein the cyclic shift is based on multiple transmit antennas and the continuation of the short training sequence.

Preferably, for each transmit antenna in the multiple-input multiple-output wireless communication system, the method further includes:

Another guard interval is generated immediately after the fourth channel sounding field;

generating a second signal detection field after the further guard interval;

According to one aspect of the present invention, the radio frequency transmitter consists of the following parts:

a baseband processing module operatively connected to convert output data into an output stream of symbols;

an operatively connected transmitter section for converting the output symbol stream into an output radio frequency signal, wherein the base processing module is operatively connected to:

for each transmit antenna of the transmitter section, generating a carrier detect field, wherein the carrier detect field is cyclically shifted from one transmit antenna to the other transmit antenna;

For the first set of transmit antennas in the transmitter section:

Immediately after the carrier detection field generates the first guard interval;

Following the first guard interval, at least one channel sounding field is generated, wherein the at least one channel sounding field is cyclically shifted from one of the first set of transmit antennas to the other following the first guard interval:

If the transmitter part contains antennas other than the first group of transmitting antennas, for the other group of transmitting antennas:

generating another at least one channel sounding field, wherein the another at least one channel sounding field is cyclically shifted from one of the other set of transmit antennas to the other immediately following the at least one channel sounding field;

generating a first guard interval before generating another at least one channel sounding field;

Preferably, for each antenna of the first set of transmit antennas of the plurality of transmit antennas in the transmitter section, the baseband processing module is still available for:

after at least one channel sounding field, generating a second guard interval;

A channel sounding field is generated after the second guard interval.

Preferably, for each antenna in another group of transmitting antennas among the plurality of transmitting antennas, the baseband processing module is also used for:

Before another at least one channel sounding field, a third guard interval is generated, wherein the first and third guard intervals last longer than the second.

Preferably, the baseband processing module can also be used to generate the carrier detection field:

A short training sequence is generated according to the original protocol, wherein the cyclic shift is based on multiple transmit antennas and the continuation of the short training sequence.

Preferably, when the number of transmitting antennas is 3, the baseband processing module can also be applied to:

For the first group of antennas in the transmitter part, the first and second long training sequences are generated according to the original protocol, which are regarded as at least one channel sounding field; wherein, the first group of antennas includes two of the three antennas , and the first and second long training sequences are cyclically shifted respectively;

Then, a third long training sequence is generated according to the original protocol, and this long training sequence is regarded as another at least one channel sounding field by another group of transmitting antennas; the "another group of transmitting antennas" mentioned here includes the aforementioned The third of the three transmit antennas.

Preferably, when the number of transmitting antennas is 4, the baseband processing module can also be applied to:

For the first group of transmitting antennas in the transmitter part, the first and second long training sequences are generated according to the original protocol, and these two long training sequences are regarded as at least one channel sounding field; wherein, the first group includes Two of the four transmit antennas, and the first and second long training sequences are cyclically shifted respectively;

Then, the third and fourth long training sequences are generated according to the original protocol, and these two long training sequences are regarded as another at least one channel sounding field by another group of transmitting antennas; wherein, another group of transmitting antennas includes four The other two of the antennas, and the third and fourth long training sequences are each cyclically shifted.

Preferably, for each of the plurality of transmit antennas in the transmitter section, the baseband processing module is still available for:

generating another guard interval immediately after another at least one channel sounding field;

And a second channel sounding field is generated after this another guard interval.

According to one aspect of the present invention, the radio frequency transmitter consists of the following parts:

a baseband processing module operatively connected to convert output data into an output symbol stream; and

an operatively connected transmitter section for converting the output symbol stream into an output radio frequency signal, wherein the baseband processing module is operatively connected to:

generating, for each transmit antenna of the plurality of antennas in the transmitter section, a carrier detect field, wherein the carrier detect field is cyclically shifted from one transmit antenna to another transmit antenna;

For the first transmit antenna in the transmitter section:

Immediately after the carrier detection field generates the first guard interval;

Immediately following the first guard interval, the first channel sounding field is generated;

generating a second channel sounding field next to the first channel sounding field;

For each transmit antenna in the first set of the remaining transmit antennas of the multiple sets of antennas:

generate a third channel sounding field;

Immediately following the third channel sounding field, a fourth channel sounding field is generated;

And generate the second guard interval before generating the third channel sounding field;

Preferably, when the number of transmitting antennas is 3, the baseband processing module can also be applied to:

The third and fourth channel sounding fields are respectively shifted from one to the other of the transmit antennas of the first group.

Preferably, when the number of transmitting antennas is 4, the baseband processing module can also be applied to:

Fourth antenna in multiple transmit antennas:

generate a fifth channel sounding field;

generating a sixth channel sounding field after the fifth channel sounding field;

And, generate a third guard interval before generating a fifth channel sounding field;

Preferably, for each antenna in the multiple transmit antennas, the baseband processing module can also be applied to:

Generate another guard interval after the sixth channel sounding field;

Generate a channel sounding field after the second guard interval;

Preferably, for the first antenna in the multiple transmit antennas, the baseband processing module is also applied to:

Immediately following the second channel sounding field produces another guard interval;

A channel sounding field is generated immediately after the second guard interval;

Preferably, the baseband processing module can also be used to generate a carrier detection field in the following manner:

A short training sequence is generated according to the original protocol, wherein the cyclic shift is based on multiple transmit antennas and the continuation of the short training sequence.

For each transmit antenna in the MIMO wireless communication system, the baseband processing module can still be used for:

Immediately following the fourth channel sounding field generates another guard interval;

A second channel sounding field is generated after this other guard interval.

Description of drawings

Fig. 1 is a functional block diagram of a wireless communication system according to the present invention;

Fig. 2 is a functional block diagram of a wireless communication device according to the present invention;

3 is a functional block diagram of another wireless communication device according to the present invention;

Fig. 4 is the functional block diagram of a radio frequency transmitter according to the present invention;

Fig. 5 is a functional block diagram of a radio frequency receiver according to the present invention;

6 is a functional block diagram of an access point communicating with a wireless communication device according to the present invention;

Fig. 7 is a description diagram of a wireless communication according to the present invention;

FIG. 8 is a descriptive diagram of a multiple-input multiple-output wireless communication according to the present invention;

FIG. 9 is a diagram illustrating preamble information for a frame cyclically shifted between two transmit antennas according to the present invention;

FIG. 10 is a diagram illustrating the preamble information of a frame suitable for sparse symbols and dual audio for cyclic shifting between two transmitting antennas according to the present invention;

FIG. 11 is a diagram illustrating preamble information for a frame cyclically shifted among three transmit antennas according to the present invention;

FIG. 12 is a diagram illustrating another preamble information for a frame cyclically shifted among three transmit antennas according to the present invention;

FIG. 13 is a diagram illustrating the preamble information of a frame suitable for sparse symbols and dual audio for cyclic shifting among three transmitting antennas according to the present invention;

14 is a diagram illustrating preamble information for a frame cyclically shifted among four transmit antennas according to the present invention;

FIG. 15 is a diagram illustrating another preamble information for a frame cyclically shifted among four transmit antennas according to the present invention;

Fig. 16 is a descriptive diagram of the preamble information of a frame suitable for sparse symbols and dual audio for cyclic shifting among four transmitting antennas according to the present invention;

Fig. 17 is a descriptive diagram of another wireless communication according to the present invention;

Fig. 18 is a descriptive diagram of another multiple-input multiple-output wireless communication according to the present invention;

FIG. 19 is a diagram illustrating the preamble information of a frame partially using the original protocol for cyclic shifting between two transmitting antennas according to the present invention;

FIG. 20 is a diagram illustrating the preamble information of a frame partially using the original protocol for cyclic shifting among three transmitting antennas according to the present invention;

FIG. 21 is a diagram illustrating the preamble information of a frame partially using the original protocol for cyclic shift among four transmit antennas according to the present invention;

Fig. 22 is a diagram illustrating another wireless communication according to the present invention;

Fig. 23 is a description diagram of yet another multiple-input multiple-output wireless communication according to the present invention;

Fig. 24 is a logic diagram of a multi-user protocol communication method according to the present invention;

Fig. 25 is a logical diagram of a method for monitoring the success of wireless multi-user protocol communication according to the present invention;

Fig. 26 is a logic diagram of a method for a wireless communication device to participate in multi-protocol communication according to the present invention;

Fig. 27 is a logic diagram of another method for a wireless communication device to participate in multi-protocol communication according to the present invention;

Fig. 28 is a logic diagram of another method for a wireless communication device to participate in multi-protocol wireless communication according to the present invention;

Fig. 29 is a description diagram of simultaneous two-channel sounding fields according to the present invention;

Fig. 30 is a description diagram of another simultaneous two-channel sounding field according to the present invention;

Fig. 31 is a description diagram of yet another simultaneous two-channel sounding field according to the present invention;

Fig. 32 is a description diagram of yet another simultaneous two-channel sounding field according to the present invention.

Detailed ways

1 is a schematic diagram of a communication system 10 that includes a plurality of base stations and/or access points 12-16, a plurality of wireless communication devices 18-32, and network hardware 34. As shown in FIG. Wireless communication devices 18-32 may be portable computers 18 and 26, personal digital assistants 20 and 30, personal computers 24 and 32, and cellular telephones 22 and 28. Details about these wireless communication devices are described in more detail in FIGS. 2 and 3 .

Base stations or access points 12-16 are connected to network hardware 34 via local area network connections 36, 38 and 40. The network hardware 34 may be a router, switch, bridge, modem, or system controller, which provides the wide area network connection 42 for the communication system 10 . Each base station or access point 12-16 has an interconnected antenna or group of antennas for communicating with wireless communication devices in its area, such devices are collectively referred to as basic service devices 9,11,13. Typically, a wireless communication device receives service from the communication system 10 after registering with a particular base station or access point 12-14. In the case of a direct connection for point-to-point communication, wireless communication devices can communicate via a dedicated channel, thus creating a dedicated network.

Typically, base stations are used for communications in cellular telephone systems and similar systems, and access points are used for indoor or in-building wireless networks. Regardless of the particular type of communication system, each wireless communication device has an integrated radio or/and is connected to a radio. The wireless device includes a highly linear amplifier or/and a programmable multi-stage amplifier, which is used to improve performance, reduce cost, reduce size and/or enhance broadband applications.

FIG. 2 is a schematic diagram of a wireless communication device, which includes master devices 18 - 32 and an interconnected wireless device 60 . For cellular telephones, the wireless device 60 is a built-in component. For PDAs, laptops, and/or personal computers, wireless device 60 may be a built-in or externally connected component.

As shown, the main device 18 - 32 includes a processing module 50 , memory 52 , wireless interface 54 , input interface 58 and output interface 56 . The processing module 50 and the memory 52 execute relevant instructions input by the master device. For example, for a master device of a cellular phone, the processing module 50 performs related communication functions according to a particular cellular phone standard.

The wireless interface 54 can receive data from the wireless device 60 and can also transmit data to the wireless device 60 . Upon receiving data (eg, input data) from the wireless device 60 , the wireless interface 54 provides the data to the processing module 50 for further processing and/or routing to the output interface 56 . The output interface 56 can be connected to an output display device so that the received data can be displayed, and the display device includes a display, a monitor, a speaker, and the like. The wireless interface 54 may also provide data from the processing module 50 to the wireless device 60 . The processing module 50 can receive data from an input device via the input interface 58 , or generate data by itself. The input device includes a keyboard, a keypad, a microphone, and the like. For the data received through the input interface 58 , the processing module 50 has a corresponding host function, and transmits the data to the wireless device 60 through the wireless interface 54 after processing.

The wireless device 60 includes: a main interface 62, a digital reception processing module 64, a memory 75, a digital transmission processing module 76 and a wireless transceiver. The wireless transceiver includes: an analog-to-digital converter 66, a filter/gain module 68, a down-conversion module 70, a receive filter 71, a low-noise amplifier 72, a transmit/receive switch 73, a local oscillator module 74 , a digital-to-analog converter 78 , a filter/gain module 80 , an upconversion module 82 , a power amplifier 84 , a transmit filter 85 and an antenna 86 . The antenna 86 may be a single antenna shared by the transmission path and the reception path controlled by the transmission/reception switch 73, or may be an antenna group independently used by the transmission path and the reception path. Which antenna to use depends on the particular standard used by the wireless communication device.

After the digital reception processing module 64 and the digital transmission processing module 76 synthesize and process the operation instructions stored in the memory 75, they respectively complete the functions of the digital reception module and the digital transmission module according to one or more wireless communication standards, and further complete the functions shown in Fig. 3- One or more aspects of the functionality described in 11. Digital reception functions include, but are not limited to: transfer of digital IF to baseband, demodulation, constellation demapping, decoding and/or descrambling. Digital transmission functions include, but are not limited to: interference release, encoding, constellation mapping, modulation, and conversion from digital baseband to IF. The digital reception processing module 64 and the digital transmission processing module 76 can be constructed in three ways: using a shared processing device, using a processing device for each, and using multiple processing devices. Such processing devices may be microprocessors, microcontrollers, digital signal processors, microcomputers, central processing units, field programmable gate arrays, programmable logic devices, state machines, logic circuits, analog circuits, digital circuits, and other Any device that can control signals (analog and digital) according to operational instructions. The memory 75 may be a single memory or a group of memories. These memories may be read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, or/and any other devices capable of storing digital information. Note that when the 64 or 76 processing module performs one or more functions through a state machine, analog circuit, digital circuit or logic circuit, the memory storing the relevant operation instructions will be embedded by the state machine, analog circuit, digital circuit and/or logic circuits to generate circuits.

In actual operation, the wireless device 60 receives external data 94 sent from the host device and input via the host interface 62 . The main interface 62 transmits the external data 94 to the digital transmission processing module 76, and then the digital transmission processing module 76 processes the external data 94 according to a specific wireless communication standard (such as IEEE802.11 and related versions, Bluetooth and related versions) to obtain a digital transmission format Data96. The digital transmission format data 96 is a digital baseband signal or a lower digital intermediate frequency signal. The lower intermediate frequency mentioned here specifically refers to the frequency from 100 kHz to several megahertz.

The digital-to-analog converter 78 converts the digital transmission format data 96 from the digital domain to the analog domain, and the filter/gain module 80 filters and adjusts the acquired analog signal, and then transmits the signal to the intermediate frequency synthesis part 82 . The intermediate frequency synthesis part 82 converts the analog baseband or lower intermediate frequency signal into a radio frequency signal based on the transmission local oscillator 83 provided by the local oscillator module 74 . The power amplifier 84 amplifies the radio frequency signal to obtain an output radio frequency signal 98, which is then filtered by the transmission filter 85. Filtered RF signal 98 is transmitted by antenna 86 to target devices such as a base station, access point, and other wireless communication devices.

Wireless device 60 may also receive incoming RF signals 88 via antenna 86 transmitted by base stations, access points, and other wireless communication devices. The antenna 86 provides the input radio frequency signal 88 to the receiving filter 71 via the transmit/receive switch 73, and the receiving filter 71 bandpass filters the input radio frequency signal 88. The receive filter 71 provides the filtered RF signal 88 to the LNA 72, which amplifies to obtain an amplified input RF signal. The low noise amplifier 72 provides the amplified input radio frequency signal to the intermediate frequency mixing module 70, and the intermediate frequency mixing module 70 directly converts the amplified input radio frequency signal into an input lower intermediate frequency signal or baseband signal. The intermediate frequency mixing module 70 provides the input lower intermediate frequency signal or baseband signal to the filter/gain module 68, and the filter/gain module 68 filters and acquires the input lower intermediate frequency signal or baseband signal to obtain a filtered input signal.

The analog-to-digital converter 66 converts the filtered input signal from the analog domain to the digital domain to obtain data 90 in a digital reception format. After the digital receiving processing module 64 decodes, descrambles, demaps and demodulates the digital receiving format data 90 according to the specific wireless communication standard adopted by the wireless device 60 , the input data 92 is recovered. Host interface 62 provides recovered input data 92 to devices 18-32 via wireless interface 54.

Those skilled in the art can understand that the wireless communication device shown in FIG. 2 can be implemented by using one or more integrated circuits. For example, the master device can be completed with one integrated circuit, the digital reception processing module 64, the digital transmission processing module 76 and the memory 75 can be completed with a second integrated circuit, and other components in the wireless device 60 except the antenna 86 can be completed with a third integrated circuit. Another way is: the wireless device 60 is completed with only one integrated circuit; there is another way: the processing module 50, the digital reception processing module 64 and the digital transmission processing module 76 in the master device can be an integrated Common processing equipment on the circuit, the memory 52 and the memory 75 can be a separate integrated circuit, and/or can be a common processing module composed of the processing module 50, the digital reception processing module 64, and the digital transmission processing module 76. integrated in the same integrated circuit.

FIG. 3 is a schematic diagram of a wireless communication device, which includes a main device of 18-32 devices and a connected wireless device 60 . For cellular telephones, the radio 60 is a built-in component. As for personal digital assistants, laptop computers and PC hosts, the wireless device 60 can be a built-in component or an externally connected component.

The wireless device 60 includes a main interface 62, a baseband processing module 63, a memory 65, a plurality of radio frequency transmitters 67, 69, 71, a transmission/reception module 73, a plurality of antennas 81, 83, 85, and a plurality of radio frequency receivers 75, 77, 79 and a local oscillator module 99. After the baseband processing module 63 is combined with the operation instructions stored in the memory 65, the digital receiving function and the digital transmitting function can be completed separately. Digital reception functions include but are not limited to: digital IF conversion to baseband, demodulation, constellation demapping, decoding, deinterleaving, fast Fourier transform, cyclic front shifting, space-time decoding and descrambling. Digital transmission functions include, but are not limited to: interference release, coding, interleaving, constellation mapping, modulation, inverse fast Fourier transform, cyclic prefix appending, space-time coding, and digital baseband to IF conversion. The baseband processing module 63 can be realized with one or more processing devices, such processing devices can be: microprocessor, microcontroller, digital signal processor, microcomputer, central processing unit, field programmable gate array, programmable logic Devices, state machines, logic circuits, analog circuits, digital circuits and any other devices that can control signals (analog signals and digital signals) according to operation instructions. The memory 66 may be a single memory or a memory group. These memories can be: read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory and any other devices that can store digital information. Note that when the 63 processing module performs one or more of its functions via a state machine, analog circuit, digital circuit or logic circuit, the memory storing the relevant operation instructions will be embedded by the state machine, analog circuit, digital circuit or Go to the circuit generated by the logic circuit.

In operation, the wireless device 60 receives output data 87 from the host device via the host interface 62 . After receiving the output data 87 , the baseband processing module 63 generates one or more output symbol streams 89 based on the mode selection signal 101 . Mode selection signal 101 represents a specific mode on the mode selection list. For example, in Table 1, the mode selection signal 101 represents a frequency band of 2.4G Hz, a channel bandwidth of 20 or 22M Hz, and a maximum bit rate of 54M bits per second. In the general table, the mode selection signal may represent a specific bit rate ranging from 1 Mbit per second to 54 Mbit per second. In addition, the mode selection signal also represents a specific type of modulation, including but not limited to: Barker code modulation, binary phase shift keying, quadrature phase shift keying, complement code keying, hexadecimal positive Cross-phase shift keying and 64-ary quadrature phase-shift keying. Table 1 also clarifies that: while providing the coding rate, it also provides the quantity of the following indicators: the number of coded bits per subcarrier wave (NBPSC), the number of coded bits per OFDM signal (NCBPS), the number of data bits per OFDM signal (NDBPS), the number of decibel error vectors, and the sensitivity indicating the maximum receiving capability (need to achieve a target packet loss rate, such as IEEE802.11a is 10 %), the number of adjacent channel rejection (ACR) and the number of alternate adjacent channel rejection (AACR).

The mode selection signal can also represent the specific channelization of the relevant mode. Table 2 illustrates the relevant mode information in Table 1. Table 2 contains the number of channels and the associated IF. The mode selection signal can also represent a probability density mask value, and Table 3 illustrates the probability density mask values in Table 1. The mode selection signal in Table 4 may also represent a frequency band of 5G Hz, a channel bandwidth of 20M Hz, and a maximum bit rate of 54M bits per second. If this is a particular mode selection, channelization is illustrated in Table 5. In addition, the mode selection signal 102 can also represent a frequency band of 2.4G Hz, a channel bandwidth of 20M Hz, and a maximum bit rate of 192M bits per second, which is illustrated in Table 6. Multiple antennas are used in Table 6 to obtain higher bandwidth, in this case the mode selection also represents the number of antennas used. Table 7 illustrates the multiplexing configured in Table 6. Table 8 illustrates another mode selection. In this mode selection, the frequency band is 2.4G Hz, the channel bandwidth is 20M Hz, and the maximum bit rate is 192M bits per second. Accordingly, Table 8 includes various bit rates ranging from 12 Mbits per second to 216 Mbits per second using 2-4 antennas and specified space-time coding rates. Table 9 illustrates multiplexing for Table 8. The mode selection signal 102 can also represent the specific operation mode set forth in Table 10. The frequency band of this specific operation mode is 5G Hz, the channel bandwidth is 40M Hz, and the maximum bit rate is 486M bits per second. In Table 10, the range of the bit rate after using 1-4 antennas and the corresponding space-time coding rate can be between 13.5 Mbits per second and 486 bits per second. Table 10 also illustrates the coding rate and number of coded bits per subcarrier (NBPSC) value for a particular modulation scheme. Table 11 provides the probability density mask for Table 10 and Table 12 provides the multiplexing for Table 10.

Baseband processing module 63 generates one or more output symbol streams 89 from output data 88 based on mode select signal 101 . For example, the baseband processing module 63 will generate a single output symbol stream 89 if the mode select signal 101 represents that a single transmit antenna is being used in a particular mode that has been selected. Alternatively, if the mode selection signal represents 2, 3 or 4 antennas, the baseband processing module 63 will generate 2, 3 or 4 output symbol streams 89 from the output data 88 depending on the number of antennas.

Depending on the number of output symbol streams produced by the baseband module 63, a corresponding number of radio frequency transmitters 67, 69, 71 can convert the output symbol stream 89 into an output radio frequency signal 91. The switching process of the RF transmitters 67, 69, 71 will be further described in FIG. 4 . After receiving the output radio frequency signal 91, the transmitting/receiving module 73 provides each radio frequency signal to the corresponding antenna 81, 83, 85.

The transmit/receive module 73 receives one or more incoming RF signals transmitted via the antennas 81 , 83 , 85 when the wireless device 60 is in receive mode. The transmit/receive module 73 provides an input radio frequency signal 93 to one or more radio frequency receivers 75 , 77 , 79 . The radio frequency receivers 75 , 77 , 79 are described in more detail in FIG. 4 , which convert an input radio frequency signal 93 into a corresponding number of input symbol streams 95 . The number of input symbol streams 95 is related to the particular mode of data received (recall that the mode employed could be any of those shown in Tables 1-12). The baseband processing module 63 receives the input symbol stream 89 and converts them into input data 97, which is transmitted to the host device 18-32 via the host interface 62.

Those skilled in the art can understand that the wireless communication device shown in FIG. 3 can be completed with one or more integrated circuits. For example, the master device can be completed with one integrated circuit, the baseband processing module 63 and the memory 65 can be completed with a second integrated circuit, and other components in the wireless device 60 except antennas 81, 83, 85 can be completed with a third integrated circuit. The circuit is completed; another way is: the whole wireless device 60 is completed with only one integrated circuit; another way is: the processing module 50 and the baseband processing module 63 in the master device can be a common processing that can be completed by using an integrated circuit device, the memory 52 and the memory 75 may be separate integrated circuits, or may be integrated into the same integrated circuit with the common processing module composed of the processing module 50 and the baseband processing module 63 .

Figure 4 is a block diagram of a radio frequency transmitter 67,69,71. The radio frequency transmitter includes: a digital filtering and uplink sampling module 475 , a digital-to-analog conversion module 477 , an analog filter 479 , an up-conversion module 481 , a power amplifier 483 and a radio frequency filter 485 . After receiving an output symbol stream 89, the digital filtering and upsampling module 475 digitizes and filters it, and then upsamples the ratio of the symbol stream to a desired ratio to obtain a filtered symbol stream 487. The digital-to-analog conversion module 477 converts the filtered symbol stream 487 into an analog signal 489 . The analog signal includes a synchronous component and a quadrature component.

The analog filter 479 filters the analog signal 489 to obtain a filtered analog signal 491 . The up-conversion module 481 includes a pair of mixers and a filter, which mixes the filtered analog signal 491 with the local oscillation 493 generated by the local oscillation module 99 to obtain a high-frequency signal 495 . The frequency of the high frequency signal 495 is related to the frequency of the radio frequency signal 492 .

The power amplifier 483 amplifies the high frequency signal 495 to obtain an amplified high frequency signal 497 . The radio frequency filter 485 as a high frequency bandpass filter filters the amplified high frequency signal 497 to obtain the desired output radio frequency signal 91 .

As can be understood by those skilled in the art, each of the RF transmitters 67, 69, 71 includes a frame similar to that described in FIG. 4, and also includes a shutdown mechanism. This mechanism allows a particular radio frequency transmission to be stopped when it is not needed so that interfering signals and noise are not generated.

FIG. 5 is a functional block diagram of one of the radio frequency receivers 75,77,79. In this embodiment, each RF receiver includes: an RF filter 501, a low noise amplifier (LNA) 503, a programmable gain amplifier (PGA) 505, a down conversion module 507, an analog filter 509 , an analog-to-digital conversion module 511 and a digital filtering and downsampling module 513 . The radio frequency filter 501 as a high frequency bandpass filter receives and filters the input radio frequency signal 93 to obtain the filtered input radio frequency signal. Low noise amplifier 503 amplifies filtered input radio frequency signal 93 at an acquisition device and provides the amplified signal to programmable acquisition amplifier 505 . The programmable acquisition amplifier 505 further amplifies the input RF signal 93 and provides it to the down conversion module 507 .

The frequency down conversion module 507 is composed of a pair of mixers, a synthesis module and a filter. It mixes the input RF signal with the local oscillator (LO) generated by the local oscillator module to obtain an analog baseband signal. The analog filter 509 filters the analog baseband signals and then provides them to the analog-digital conversion module 511, and the analog-digital conversion module 511 converts them into digital signals. The digital filtering and down-sampling module 513 filters the digital signal and adjusts its sampling rate to obtain the input symbol stream 95 .

FIG. 6 is a functional block diagram of an access point 12-16 in communication with wireless communication devices 25,27,29. The wireless communication devices 25, 27, 29 may be any of the devices 18-32 described in Fig. 1 to Fig. 3 . In the figure, the access points 12-16 include: a processing module 15, a memory 17 and a wireless transceiver 19. The wireless transceiver 19 has the following characteristics: the wireless transceiver of each wireless communication device on the frame can be similar; in the maximum range or in the basic service device, it includes multiple antennas, multiple transmission paths and Multiple receive paths. The processing module 15 may be a single processing device or multiple processing devices. Such processing devices may be: microprocessors, microcontrollers, digital signal processors, microcomputers, central processing units, field programmable gate arrays, programmable logic devices, state machines, logic circuits, analog circuits, digital circuits, And any other equipment that can control signals (analog signals and digital signals) according to operating instructions. The storage 17 may be a single storage device or multiple storage devices. Such storage devices may be read-only memory, random-access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, cache memory, and/or any other memory that can hold digital information equipment. Note that when the processing module 15 performs one or more functions through a state machine, analog circuit, digital circuit and/or logic circuit, a memory storing relevant operation instructions will be embedded in it, or externally connected to the state machine, digital circuit and/or logic circuit. Circuits produced by analog circuits, digital circuits and/or logic circuits. The memory 17 and the processing module 15 respectively store and execute operation instructions of some related steps and related functions described in FIGS. 7-32 .

In the figure, each wireless communication device 25, 27, 29 uses a different wireless communication protocol. The wireless communication device 25 adopts the A35 communication protocol, the wireless communication device 27 adopts the B37 communication protocol, and the wireless communication device 29 adopts the C39 communication protocol. For example, A, B, C could be three protocols associated with different versions of the IEEE 802.11 standard. For example, Protocol A is related to IEEE 802.11b, Protocol B is related to IEEE 802.11g, and Protocol C is related to IEEE 802.11n.

These protocols need to be sorted according to a protocol sorting table, and the protocol sorting table has already arranged protocol A, protocol B, and protocol C in sequence. Such ordering may be based on the historical order associated with each protocol, such that the first protocol in the ordering list is the oldest standard and the last in the ordering list is the newest standard. For example, in the figure, protocol A is related to IEEE 802.11b, protocol B is related to IEEE 802.11g, and protocol C is related to IEEE 802.11n. Alternatively, the protocol sort table can be sorted based on a user- and system administrator-defined program. For example, when protocol A is used in an established wireless communication system, if the number of transmission errors due to unrecognizable information frames is too large to be tolerated, users can choose to use protocol B format to build a wireless communication system. This concept will be described in more detail in the remaining figures.

In operation, in the central area, the access points 12-16 and/or the respective wireless communication devices 25, 27, 29 determine the protocols used by the wireless communication devices. A central area that may contain the basic service set and/or adjacent basic service set and/or a direct or temporary direct communication network of these wireless communication devices is retrieved. Once each wireless communication device has determined the communication protocol, the access point 12-16 and/or the wireless communication device 25-29 determines which protocol to use to set up the wireless communication based on the protocol instructions. For example, if protocol A is IEEE 802.11b, the communication device will use the MAC level protection mechanism to establish wireless communication, which will be further detailed in Figure 22. In this way, each wireless communication device will use protocol A to set up or establish wireless communication. In this wireless communication, the original device can identify the wireless communication being established and the duration of the wireless communication. In order to avoid conflicts, in It will not be sent during this time.

Once the wireless communication is set or established, the communication device transmits data using the protocol selected from the protocol instruction (such as protocol A) in the subsequent communication. The wireless communication device 27 sets up a wireless communication using protocol A and then transmits corresponding data in the wireless communication using protocol B. Similarly, the wireless communication device 29 establishes or sets up wireless communication using protocol A and then uses protocol C to communicate data in the wireless communication.

Those of ordinary skill in the art can understand that if the central area only includes wireless communication devices using the same protocol, then the setting and data transmission also use the same protocol. Those skilled in the art should also understand that if there are only two different protocols in the central area, the old protocol will be selected as the set protocol.

FIG. 7 is a diagram illustrating wireless communication between two wireless communication devices 100 and 102 in a central area using only the IEEE 802.11n protocol. Wireless communication can occur directly (from a wireless communication device to another wireless communication device) or indirectly (from one wireless communication device to an access point to another wireless communication device). In this example, wireless communication device 100 provides frame 104 to wireless communication device 102 . Frame 104 includes a wireless communication setting information field 106 and data portion 108 . The wireless communication setting information part 106 includes a short training sequence 157 of 8 microseconds long, a first supplementary long training sequence 159 of 4 microseconds long, which is one of a plurality of supplementary long training sequences 161, and a signal field 163 is 4 microseconds long. Note that the number of supplementary long training sequences 159, 161 is consistent with the number of antennas used in MIMO wireless communication.

The data portion of frame 104 includes a plurality of data symbols 165, 167, 169 lasting 4 bit microseconds. The last data symbol 169 also contains a necessary last bit and padding bits.

FIG. 8 is a diagram illustrating wireless communication between two wireless communication devices 100 and 102 in a central area using only the IEEE 802.11n protocol. Wireless communication can occur directly (from a wireless communication device to another wireless communication device) or indirectly (from one wireless communication device to an access point to another wireless communication device). In this example, wireless communication device 100 provides multiple frames 104-1, 104-2, 104-N to wireless communication device 102 using multiple antennas #1-#N. Each of the frames 104-1, 104-2, 104-N includes a wireless communication setup information field 106 and a data portion 108. The wireless communication setting information part includes an 8 microsecond short training sequence 157, a 4 microsecond long first supplementary long training sequence 159, which is one of a plurality of supplementary long training sequences 161, and the signal field 163 is 4 microseconds long. Note that the number of supplementary long training sequences 159, 161 is consistent with the number of antennas used in MIMO radio communication.

The data portion of frame 104 includes a plurality of data symbols 165, 167, 169 lasting 4 bit microseconds. The last data symbol 169 also contains a necessary last bit and padding bits.

In this case, there is a preamble (sometimes referred to as "greenfield") only if the .11n device is present. Alternatively, legacy equipment (.11, .11a, .11b, and .11g) will use the preamble when MAC level (RTS/CTS or CTS alone) protection is used. (When the original base station cannot protect a very long character group, MAC level protection can also be used).

The short training sequence 157 may be the same as the TX antenna in 802.11a. For antennas 2 to N is a cyclically shifted version of the same sequence. In the preferred mode, the number of cyclic shifts for each antenna is calculated by (number of antennas - 1)*800/N in nanoseconds. For 1 antenna, the shift is zero. For 2 antennas, the shift of antenna 1 is 0 ns and 400 ns. For 3 antennas, the shifts are 0, 250, and 500 ns. For 4 antennas, the shifts are 0, 200, 400, and 600 ns. When shifted by about 50ns (inversion of the symbol clock frequency), it is very simple to implement. Shift or forward or backward.

Complementary long training sequences 159, 161: (m=1) There are several implementation possibilities. In this case there is only one long training sequence 159 . For antenna 1, the 802.11a long training sequence 159 is the same but only 4 microseconds long, including a guard interval of 0.8 microseconds. For antennas 2 to N it is a cyclic shift scheme of the same sequence. In the preferred mode, the number of cyclic shifts of each antenna is calculated by passing (number of antennas-1)*4/N in microseconds. For 1 antenna, the shift is 0. For 2 antennas, the shift of antenna 1 is 0 and 4us. For 3 antennas, the shift is 0, 2.65us, 5.35us. For 4 antennas, the shifts are 0, 2, 4, and 6 microseconds. Once again, when shifted by about 50ns (inversion of the symbol clock frequency), it is very simple to execute. Or shift forward or backward.

For (m=N), the number of training sequences and the number of transmit antennas are equal. This is preferably the (m=1) case, as this will reduce channel estimation errors on reception, especially for very many antennas. Therefore it is scalable. There are two possible choices for the training sequence:

Null Space - In this case, the sequences (1,1), (2,2), (3,3), ... to (N,N) are all the same as the 802.11a long training sequence. All other ((1,2), (2,1) etc.) sequences are empty - in those time slots, no data is transmitted.

Subchannel Empty - In this case, the set of subchannels in the training sequence is subdivided by the number of transmit antennas. A single subset is activated in each sub-training interval.

An orthogonal sequence is obtained by multiplying the subcarrier of the 802.11a long sequence by an m*m orthogonal matrix (for example, a matrix for generating discrete Fourier transform).

FIG. 9 is a diagram illustrating preamble information of frames 104-1, 104-2 using a cyclic shift of two antennas. Communication devices in the central area include only 802.11a compliant devices. Preamble information is a part of wireless communication setup information, which includes a short training sequence (STS) 157, a long training sequence (LTS) 159 & 161, a signal field (SIG1) 224 and a data field or another signal field 228. For the first antenna frame 104-1, the STS 157 is split into two parts of symbols 232,234. In the example, the STS 157 includes 10 symbols of 800 ns per previous 802.11x command. The LTS 159 & 161 of the first antenna frame 104-1 includes a double guard interval (GI2) 236 lasting 1600 ns, which is equivalent to the LTS 159 & 161 lasting 1600 ns when the LTS 159 & 161 is considered in advance.

The LTS 159&161 of the first antenna frame 104-1 includes a two-time repeated long training sequence in accordance with the previous 802.11x version instructions, and the dual tone of the LTS is divided into 238 and 240. Signal field 224 and optional second field 228 contain the previously discussed information, which are separated by guard intervals (GI) 220 and 226 .

The preamble of the second antenna frame 104-2 includes similar parts as the preamble of the first antenna, but the STS 157 and LTS 159 & 161 are cyclically shifted. As shown in the figure, in STS 157, the second part of symbol 234 is prior to the first part of symbol 234, and this timing is opposite to the preamble information of the first antenna. It is further shown that STS 157 includes 10 symbols divided into two parts, the first part includes symbols 0-5, and the second part includes symbols 6-9. For the first antenna, the first part of the symbol 232 just precedes the second part 234, and for the second antenna, the second part 234 just precedes the first part 232. In an example, the cyclic shift might be 400-1600ns.

The LTS mode of each LTS field 159 & 161 can be divided into two parts 238, 240 as shown. For the first antenna frame 104-1, the first part of the dual tone 238 just precedes the second part of the dual tone 240. The second portion 240 just precedes the first portion 238 for the second antenna frame 104-2. Thus, the LTS 159 & 161 of the second antenna frame 104-2 represent a cyclic shift of the LTS 159 & 161 of the first antenna frame 104-1.

FIG. 10 is a diagram illustrating a frame 104-1, 104-2 using different forms of cyclically shifted preamble information using phase symbols and/or dual-tone transmit antennas. The communication devices here are in the central area including only 802.11n compliant devices. The preamble information is a part of the wireless communication setup information 106, and includes a short training sequence (STS) 157, a long training sequence (LTS) 159 & 161, a signal field (SIG1) 224, a data field or another signal field 228 and two guard intervals 220,226. In this example, the symbols of the STS 157 are split into two parts 232, 234. The first portion 232 is contained in the first antenna frame 104-1 and the second portion 234 of symbols is contained in the second antenna frame 104-2. The illustration includes an example of dividing the symbols into 232, 234, in this example the STS157 includes 10 symbols per previous version 802.11x instructions. The LTS 159 & 161 of the first antenna frame 104-1 includes a double guard interval (GI2) 236 lasting 1600 ns, which is equivalent to the LTS lasting 1600 ns when the LTS is considered in advance.

LTS 159 & 161 consist of a twice repeated long training sequence equivalent to previous 802.11x commands, and the dual tone of LTS is split into two parts 238, 240. The first portion 238 of the dual tone is contained in the first antenna frame 104-1 and the second portion 240 of the dual tone is contained in the second antenna frame 104-2.

FIG. 11 is a diagram illustrating the preamble information of frames 104-1,-2,-3 using a cyclically shifted three-antenna. The communication devices here are in the central area including only 802.11n devices. Preamble information is a part of wireless communication setting information, it includes a short training sequence (STS) 157, a long training sequence (LTS) 159 & 161, a signal field (SIG1) 224 and a data field or another signal field 228 and two Guard intervals 220,226. For the first antenna frame 104-1, the STS 157 is divided into three parts 250, 252, 254. In an example, the STS 157 includes 10 symbols at 800 ns per previous version of the 802.11x command, for example, the first part includes symbols 0-2, the second part 252 includes symbols 3-5, and the third part 254 includes Code elements 6-9. As one of the general techniques of the technology, it should be appreciated that other sets of symbols can be used.

The LTS 159 & 161 of the first antenna frame 104-1 includes a double guard interval (GI2) 236 lasting 1600 ns, which is equivalent to the LTS lasting 1600 ns when the LTS 159 & 161 are considered in advance. LTS 159 & 161 include a two-time repeated long training sequence in accordance with previous 802.11x version instructions, and here the dual tone of the LTS is divided into three parts 256, 258, 260. The signal field 224 and optional second field 228 contain the previously discussed information.

The preambles 104-2,-3 for the second and third antennas include similar parts as the preambles for the first antenna 104-1, but the STS 157 and/or LTS 159 & 161 are cyclically shifted. As shown, for each antenna frame 104-1, -2, -3, the three symbol portions 250, 252, 254 are sequentially cyclically shifted. In an example, the cyclic shift might be 400-1600ns.

The LTS pattern of each LTS field 159 & 161 can be divided into two parts 256, 258, 260 as shown, for the first antenna frame 104-1, the first part of the dual tone 256 just precedes the second part 258 and the second part of the dual tone 260 in three parts. For the second antenna frame 104 - 2 , the second portion 258 just precedes the first portion 256 and the third portion 260 . For the third antenna frame 104 - 3 , the third portion 260 just precedes the first portion 258 and the second portion 258 . Thus, the LTS 159 & 161 of the second and third antenna frames 104-2,-3 are cyclically shifted with respect to the LTS 159 & 161 of the first antenna frame 104-1.

FIG. 12 is another depiction of preamble information for frames 104-1, -2, -3 using cyclically shifted three transmit antennas, including an original part and a supplementary part. The original part includes STS 157 divided into three parts symbols 250, 252, 254, and LTS 159 & 161 divided into two groups of audio parts 238, 240. The supplementary section includes a guard interval 274 and a unique LTS pattern including the first and second sets of audio portions 276,278.

In this example, s1..s2 is a k*200ns cyclic shift of s0. Here k=1..2 and s1..s2 correspond to the symbols of the STS field 157 of the respective antenna frame 104-1,-2,-3. The two parts 238, 240 of the dual tone of LTS 159&161 conform to the long-term training symbols of the original 802.11a standard (3.2 microseconds, plus 1.6 microseconds prior to GI2 236), each pair of 238 and 240 are equal. Both portions of the dual tone portion 238, 240 of the second antenna frame 104-2LTS 159 & 161 are both portions of the dual tone portion 238, 240 of the first antenna frame cyclically shifted by 1.6 microseconds. The supplemental LTS of the third antenna frame 104-3 is the same as the first and second parts of the LTS pattern 238, 240 of the first antenna frame 104-1 and prepends GI2 274 (duration 1.6 microseconds). Only the first data symbol (DATA0) 272 has a pre-considered GI2 270 (duration 1.6 microseconds). All subsequent data symbols have a pre-considered GI (duration 800ns). The GI2 field 274 precedes the supplemental LTS and the GI2 field 270 precedes the first data symbol (DATA0) to allow setting of the power amplifier.

Fig. 13 is a descriptive diagram of the preamble information of a frame using a cyclic shift form, including sparse symbols and/or dual tones for three transmit antenna frames 104-1,-2,-3, where the communication device only includes Central area for 802.11n compliant devices. Preamble information is a part of wireless communication setting information, it includes a short training sequence (STS) 157, a long training sequence (LTS) 159 & 161, a signal field (SIG1) 224 and a data field or another signal field 228 and two Guard intervals 220,226. In this example, the symbol STS 157 is divided into three parts 280, 282, 284. The first portion 282 is contained in the first antenna frame 104-1, the second portion 282 is contained in the second antenna frame 104-2, and the third portion 284 is contained in the third antenna frame 104-3. The figure includes an example of dividing symbols into parts. In an example, the STS 157 includes 10 symbols per previous 802.11x command. In this example, a first portion 280 may include symbols 0,3,6, a second portion may include symbols 1,4,7, and a third portion 284 may include symbols 2,5,8.

The LTS 159 & 161 of the first antenna frame 104-1 includes a double guard interval (GI2) 236 lasting 1600 ns, equivalent to the LTS lasting 1600 ns when the LTS 159 & 161 are considered in advance. LTS 159&161 includes a two-time repeated long training sequence 159&161 in accordance with previous 802.11x version instructions, and here the dual tone of the LTS is divided into three parts 286, 288, 290. The first part 286 of the dual tone is contained in the first antenna frame 104-1, the second part 288 of the dual tone is contained in the second antenna frame 104-2, and the third part 290 of the dual tone is contained in the third antenna frame 104-2. antenna frame 104-3. For example, if a long training sequence consists of 15 tones, the first part 286 may consist of 0, 3, 6, 9, 12, the second part 288 may consist of 1, 4, 7, 10, 13, and the third part 290 may consist of 2, 5, 8, 11, 14.

Fig. 14 is a diagram illustrating the preamble information of frames 104-1, -2, -3, -4 cyclically shifted by four transmit antennas. As shown, the STS 157 is divided into four symbol parts 300, 302, 304, 306 and/or the LTS 159 & 161 are divided into four part dual tones 308, 310, 312, 314. For each antenna frame 104-1, -2, -3, -4, the symbol portions 300, 302, 304, 306 are cyclically shifted and/or the dual tone portions 308, 310, 312, 314 are cyclically shifted ground shift.

FIG. 15 is another depiction of preamble information for four transmit antenna cyclically shifted frames 104-1, -2, -3, -4. In this example, s1..s3 is a k*200ns cyclic shift s0, where k=1..3 and s1..s3 fits into the symbol portion 300, 302, 304, 306 of the STS field 157. The LTS 159 & 161 and signal fields 224 of the first and second antenna frames 104-1,-2 are discussed with reference to FIG. 12 . The supplementary LTS of the frame 104-3 of the third antenna includes first and second parts 238, 240, which are the same as the two parts 238, 240 of the LTS 159 & 161 of the frame 104-1 of the first antenna, and presupposing to GI 236 (for 1.6 microseconds). The supplemental LTS for the frame 104-4 of the fourth antenna includes the first and second parts 238, 240 of the frame 104-2 of the second antenna and prepends the GI 236 (duration 1.6 microseconds). In other words, the LTS of frame 104-4 for the fourth antenna is a 1.6 microsecond cyclic shift of the complementary LTS of the third antenna. The first data symbol (DATA0) 272 prepends GI2 270 (duration 1.6 microseconds). All data symbols are prepended with GI (duration 800 ns).

FIG. 16 is a depiction of frame preamble information for four transmit antennas using cyclically shifted sparse symbols and/or dual tones, where the communication device is in a central area including only 802.11n compliant devices. Preamble information is a part of wireless communication setting information, it includes a short training sequence (STS) 157, a long training sequence (LTS) 159 & 161, a signal field (SIG1) 224 and a data field or another signal field 228 and two Guard intervals 220,226. In this example, the symbol STS 157 is divided into four parts 320, 322, 324, 326. The first part 320 is contained in the first antenna frame 104-1, the second part 322 is contained in the second antenna frame 104-2, the third part 324 is contained in the third antenna frame 104-3, and the second part 322 is contained in the third antenna frame 104-3. Three sections 326 are included in the fourth antenna frame 104-4. The figure includes an example of dividing symbols into parts. In an example, the STS 157 includes 10 symbols per previous 802.11x command. For example, a first portion 320 may include symbols 0,4, a second portion 322 may include symbols 1,3, a third portion 324 may include symbols 2,6, and a fourth portion 326 may include symbols 3,7 .

The LTS 159 & 161 of the first antenna frame 104-1 includes a double guard interval (GI2) 236 lasting 1600 ns, equivalent to the LTS lasting 1600 ns when the LTS 159 & 161 are considered in advance. LTS 159&161 includes a two-time repeated long training sequence 159&161 in accordance with previous 802.11x version instructions, and here the dual tone of the LTS is divided into four parts 328, 330, 332, 334. The first part 328 of the dual tone is contained in the first antenna frame 104-1, the second part 330 of the dual tone is contained in the second antenna frame 104-2, and the third part 332 of the dual tone is contained in the third antenna frame 104-2. In the first antenna frame 104-3, the fourth portion 334 of the dual tone is contained in the fourth antenna frame 104-4. For example, if a long training sequence consists of 20 tones, the first part 328 may consist of 0, 4, 8, 12, 16, the second part 330 may consist of 1, 5, 9, 13, 17, and the third part 332 may consist of 2, 6, 10, 14, 18, the fourth part 334 may include 3, 7, 11, 15, 19. Note that when using the Supplementary LTS field, a dual tone in LTS mode can only be split into two parts.

FIG. 17 is a diagram illustrating wireless communication between two wireless communication devices 100 and 102 . Both devices are IEEE 802.11n compliant. The communication takes place in a central area comprising 802.11n, 802.11a and/or 802.11g compliant devices. In this example, frame 110 here includes an original setup information section 112, remaining setup information section 114 and data section 108, Wireless communication can be direct or indirect.

The old portion of setup information 112 includes a short training sequence 157 lasting 8 microseconds, a long training sequence 171 lasting 8 microseconds, and a signal field 173 lasting 4 microseconds. Signal field 173 includes several bits representing the duration of frame 110, as is known. In this way, IEEE 802.11a-compliant devices and IEEE 802.11g-compliant devices in the central area can recognize the frame being transmitted without having to decode the remainder of the frame. In this example, old devices (devices conforming to IEEE 802.11a and IEEE802.11g) can avoid communication conflicts with devices conforming to IEEE 802.11n after decoding the original part of the setting information 112 correctly.

The remaining setup information 114 includes additional supplementary long training sequences 159, 161 lasting 4 microseconds. The remaining setup information also includes a 4 microsecond high data field 163 that provides additional information about the frame. Data portion 108 includes data symbols 165, 167, 169, all of 4 microsecond duration as in FIG. In this example, the physical layer provides the original protection.

FIG. 18 is a diagram depicting wireless communication between two wireless communication devices 100 and 102 (both conforming to IEEE 802.11n). The central area where communications occur includes IEEE 802.11n compliant devices, 802.11a compliant devices and/or 802.11g compliant devices. In this example, the frames 110-1, 100-2, and 100-N here each include an original setting information part 112, a remaining setting information part 114 and a data part 108 using multiple antennas. Wireless communication can be direct or indirectly.

The original part of the setup message 112 includes a short training sequence 157 lasting 8 microseconds, a long training sequence 171 lasting 8 microseconds, and a signal field 173 lasting 4 microseconds. Signal field 173 includes several bits representing the duration of frame 110, as is known. In this way, IEEE 802.11a-compliant devices and IEEE 802.11g-compliant devices in the central area can recognize the frame being transmitted without having to decode the remainder of the frame. In this example, the original device (the device conforming to IEEE 802.11a and IEEE802.11g) can avoid conflicts with the communication of the device conforming to IEEE 802.11n after correct decoding of the original part of the setting information 112 .

The remaining setup information 114 includes additional supplementary long training sequences 159, 161 lasting 4 microseconds. The remaining setup information also includes a 4 microsecond high data field 163 that provides additional information about the frame. Data portion 108 includes data symbols 165, 167, 169, all of 4 microsecond duration as in FIG. In this example, the physical layer provides legacy protection.

In the example, m is the number of long training sequences included in each frame, N is the number of transmit antennas, and the preamble information (sometimes called "Brown field") is only used when there is a .11a or .11g device. TX antenna 1 short training sequence and long training sequence are the same as 802.11a. There are two possibilities for antennas 2 to N:

Use the same cyclic shift scheme for the same sequence. For short training sequences, the number of cyclic shifts per antenna can be calculated in nanoseconds by (number of antennas-1)*800/N and in microseconds by (number of antennas-1)*4/N.

The second mode is to leave the signal field of the short training sequence sent by antennas 2 to N empty. (That is, these antennas do not transmit during this interval). Furthermore, the complementary long training sequence for antenna 1 is not used and no information is transmitted during this time.

The signal field 173 follows the 802.11a format, except that the reserved bit (4) is set to 1 to indicate 802.11n frames and .11n reception for subsequent training. Long training sequences for supplemental training can be defined in a number of ways:

When (m=1), there is only one long supplementary training sequence 159 . It is orthogonal to the long training sequence of 802.11a.

When (m=N-1), the number of training sequences is equal to the number of transmitting antennas. This method is better than the (m=1) case because it has less channel estimation error at the receiver, especially when the number of antennas is large. Therefore, it is scalable.

There are three possible choices for the training sequence:

Null Space - In this case, the sequences (1,1), (2,2), (3,3), ..., to (m,m) are all the same as the 802.11a long training sequence. Others (like (1,2), (2,1), etc.) are empty - no information is sent in these slots.

Subchannel Empty - In this case, the set of subchannels in the training sequence is subdivided by the number of transmit antennas. A single subset is activated in each sub-training interval.

One embodiment multiplies the 802.11a long training sequence with an m*m-dimensional orthogonal matrix (such as a matrix for generating discrete Fourier transform) to obtain an orthogonal sequence, and detailed references are in FIGS. 29-32 . For example, in the case of 4 antennas, the following orthogonal matrix will be used to generate the subcarriers of each supplementary long training sequence.

FIG. 19 is a diagram illustrating preamble information of frames 104-1,-2 cyclically shifted using two transmit antennas of the original portion. As shown, STS 157 is divided into two parts of symbols 344,346. For example, the first portion 344 includes symbols 0-4 and the second portion includes symbols 5-9. The next part of the preamble of the first antenna frame 104-1 includes the old LTS 340, a guard interval 220 and a signal field 224. The supplemental LTS 342 of the second antenna frame 104-2 is the same as the LTS of the first antenna frame 104-1, but sequentially shifted.

FIG. 20 is a diagram illustrating preamble information of frames 104-1,-2,-3 cyclically shifted using the original part of the three transmit antennas. As previously stated, the STS 157 is divided into three parts of symbols 250, 252, 254. The next part of the preamble of the first antenna frame 104-1 includes the original LTS 340, a guard interval 220 and a signal field 224. The supplemental LTS 342 of the second antenna frame 104-2 is the same as the LTS of the first antenna frame 104-1, but sequentially shifted. The supplementary LTS of the third antenna frame 104-3 uses the scheme of cyclic shifting of the supplementary LTS of the second antenna. All three antenna frames 104-1,-2,-3 also include a double guard interval 336 and a data field 228.

FIG. 21 is a diagram illustrating preamble information of frames 104-1, -2, -3, -4 cyclically shifted using the original part of four transmit antennas. As previously stated, the STS 157 is divided into three parts of symbols 300, 302, 304, 306. The next part of the preamble of the first antenna frame 104-1 includes the original LTS 340, a guard interval 220 and a signal field 224. The supplemental LTS 342 of the second antenna frame 104-2 is the same as the LTS of the first antenna frame 104-1, but sequentially shifted. The supplementary LTS of the third antenna frame 104-3 uses the scheme of cyclic shifting of the supplementary LTS of the second antenna. The supplemental LTS of the fourth antenna frame 104-4 includes the old LTS unique LTS pattern, time shifted as shown, for approximately 4 microseconds.

FIG. 22 is a diagram depicting wireless communication between two wireless communication devices 100 and 102 (both conforming to IEEE 802.11n). The central area where communications occur includes IEEE 802.11n compliant devices, 802.11a compliant devices and/or 802.11g compliant devices. In this example, the frames here include an original setup information part 112 , remaining setup information part 114 and data part 108 . As shown in the figure, the 112 original part of setting information or the original frame includes an IEEE802.11PHY preamble information (STS, LTS and signal field) and a MAC delimited frame part (indicating that this special frame can be specially decoding). In this example, the MAC layer provides legacy protection.

The remaining setup information 114 includes a number of supplemental long training sequences and high data fields 163 . Data portion 108 includes a number of previously discussed data symbols.

FIG. 22 is a diagram depicting wireless communication between two wireless communication devices 100 and 102 (both conforming to IEEE 802.11n). The central area where communications occur includes IEEE 802.11n compliant devices, 802.11a compliant devices and/or 802.11g compliant devices. In this example, frame 111 includes an old setup information section 112 , remaining setup information section 114 and data section 108 . As shown, the 112 original part of the setting information or the original frame includes an IEEE802.11 PHY preamble information (STS 157, LTS 171 and signal field 173) and a MAC delimited frame part 175 (indicating that this special frame can be Special decoding of the original equipment). In this example, the MAC layer provides legacy protection.

The remaining setup information 114 includes a number of complementary long training sequences 159 , 161 and a high data field 163 . The data portion 108 includes a plurality of previously discussed data symbols 165,167,169.

FIG. 23 is a diagram depicting wireless communication between two wireless communication devices 100 and 102 (both conforming to IEEE 802.11n). The central area where communications occur includes IEEE 802.11n compliant devices, 802.11a compliant devices and/or 802.11g compliant devices. In this example, frames 111-1, 111-2, 111-3, 111-N each include an original setup information 112 section, remaining setup information section 114 and data section 108. As shown, the 112 original part of the setting information or the original frame includes an IEEE802.11 PHY preamble information (STS 157, LTS 171 and signal field 173) and a MAC delimited frame part 175 (indicating that this special frame can be special decoding for older devices). In this example, the MAC layer provides legacy protection. Note that except for the signal field, other fields are the same as those in Fig. 9 and Fig. 10 . This is another NAV method that uses MAC separation to set legacy stations. The MAC Segment contains information to encode frames that can be received by .11a and .11g at the native rate. The supplemental long training sequences 159, 161 follow the same format as previously discussed in FIG. 9 .

The remaining setup information 114 includes a number of complementary long training sequences 159 , 161 and a high data field 163 . The data portion 108 includes a plurality of previously discussed data symbols 165,167,169.

Fig. 24 is a method of multi-protocol wireless communication in WLAN. The method starts at step 120, the access point (for indirect wireless communication) or the wireless communication device (for direct wireless communication) determines the protocol of the wireless communication device in the central area. In an example, the protocol is determined by the frequency band used and the format of the WLAN communication of each wireless communication device. For example, if the frequency band is 2.4GHz, the device may have a WLAN communication format consistent with IEEE 802.11b, IEEE802.11g and/or IEEE802.11n. If the frequency band is 4.9-5.85GHz, the device can have a WLAN communication format consistent with IEEE 802.11a or IEEE.802.11n. In addition, the central area includes a basic service setup coverage area, a dedicated network coverage area and/or at least a portion of the basic service setup and at least one adjacent basic service setup coverage area. Referring to FIG. 1 , the BBSs adjacent to the access point 12 include the BBS of the access point 14 and/or the BBS of the access point 16 .

Returning to the logic diagram of FIG. 24, the process continues to step 122, where the access point and/or the wireless communication device decides which protocol to use for the communication device in the central area. The program then proceeds to step 124, at which point the branch of the process is determined by whether the protocols used by the wireless communication devices in the central area are the same. When the wireless communication devices in the central area use the same protocol, the process proceeds to step 126, at which point the wireless communication devices establish a wireless communication using their protocol and start communicating.

However, if at least one wireless communication device uses a different protocol, the program proceeds to step 128, at which point the access point or the wireless communication device selects one of the protocols of the wireless communication devices in the central area, the wireless communication device based on the protocol order to select a protocol. The order of the protocols may be based on the native order of the wireless communication device protocol and/or a protocol order based on the effective order of transmission of the protocol. For example, devices conforming to IEEE 802.11, IEEE 802.11b, IEEE 802.11g and IEEE802.11n operate in the 2.4GHz band and devices conforming to IEEE 802.11a and IEEE 802.11n operate in the 4.9-5.85GHz band. Therefore, in the 2.4GHz frequency band, if there is an 802.11n-compliant device in a 802.11b-compliant station, a MAC-level protection mechanism such as defined in 802.11g will be used, as shown in FIG. 6 . However, if only 802.11n-compliant devices represent legacy 802.11g devices, either MAC-level protection mechanisms (in Figure 6) or PHY-level protection mechanisms (in Figure 5) are used. In the 4.9-5.85GHz band, if the 802.11n-compliant device represents an 802.11a-compliant device, either MAC-level protection mechanisms or PHY-level protection mechanisms can be used.

Those skilled in the art can understand that it is more necessary to use the PHY-level protection mechanism rather than the MAC-level protection mechanism, because the additional frames of the MAC-level protection mechanism are not necessary, and the throughput impact will be reduced. If the PHY-level protection mechanism does not work well, such as the measurement of the number of acknowledgment frames exceeds a certain threshold, the MAC-level protection mechanism will be used.

Those of ordinary skill in the art will also understand that the use of legacy conditions and required protection mechanisms can be initiated by ERP cells of information frames (and probe response frames). Currently 802.11g uses bit 0 to indicate no ERP (like .11b) and bit 1 to force the base station to use protection (MAC level). Can be extended to use reserved bits (3 to 7) to represent the legacy state of the .11g or .11a base. In the example, bit 3 means "Original OFDM is present", the bits are decoded according to the following table:

bit 0 - no ERP presentation bit 1 - use protection Bit 3 - Legacy OFDM Presentation 802.11n action 0 0 0 Use .11n frames 1 1 0 Use MAC protection 1 1 1 Use MAC protection 0 1 1 Use PHY or MAC protection 0 0 1 Operationally using PHY or MAC protection

For .11n, the MAC-level protection mechanism is the same as for .11g. The base station either uses the CTS itself or the CTS/RTS exchange to set the NAV (Network Allocation Vector) of the original base station.

Returning to the logic diagram of FIG. 24, the process continues to step 130, where the wireless communication device establishes a wireless communication with the central area using the protocol selected by the central area. This is depicted in the previous figure. The program then proceeds to step 132, where the wireless communication device uses its protocol for data transmission for wireless communication.

Figure 25 is a logic diagram of a method for determining whether the selected protocol has been changed. The process begins at step 140, where the access point and/or the wireless communication device monitors the central area for data transmission to prevent transmission of unknown data. The process proceeds to step 142, where the access point and/or wireless communication device compares the transmitted unknown data to a transmission failure threshold (above approximately %5). If the comparison is positive, the program proceeds to step 146 where the selected protocol has not changed and the program repeats at step 140 .

However, if the comparison result of step 144 is unfavorable, the program proceeds to step 148, where the access point and/or wireless communication device selects another protocol of the wireless communication device in the central area, and generates another selected protocol based on the protocol sequence . For example, when too many transmission errors occur, the optional MAC layer protection mechanism replaces the PHY layer protection mechanism. The program then proceeds to step 150, where the wireless communication device establishes wireless communication using another protocol selected by the central area.

FIG. 26 is a logic diagram of a method for a wireless communication device to participate in multi-protocol wireless communication. The process begins at step 160, where the wireless communication device switches an access point (AP) using a protocol of the wireless communication device, such as IEEE 802.11n. The program then proceeds to step 162 where the wireless communication device receives the selected protocol from the access point. It is noted that the selected protocol and the protocol of the wireless communication device may be IEEE 802.11, IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, IEEE 802.11n and/or a modified version of IEEE 802.11 consistent with a wireless local area network communication format. Note also that the selected protocol includes a first frame format that includes a legacy header and a specific Media Access Control layer (MAC) delimiter field, and a second frame format that includes a physical layer backward compatible header, and/or a third frame format that includes a current version of the header and the MAC layer delimiter field.

The program then proceeds to step 164, where the wireless communication device determines whether the selected protocol is the same protocol as that of the wireless communication device. When the protocols are the same, the program branches from step 166 to step 168. If the protocol is different, the program proceeds to step 170. At step 168, the wireless communication device establishes a wireless communication using the protocol and begins transmitting data. At step 170, the wireless communication device establishes a wireless communication using the selected protocol. The program then proceeds to step 172 where the wireless communication device communicates wirelessly using its protocol.

FIG. 27 is a logic diagram of a method for a wireless communication device to participate in multi-protocol wireless communication. The process begins at step 180 where a frame is received by a wireless communication device over a wireless channel. The process then proceeds to step 182, where the wireless communication device determines whether the selected protocol and the protocol of the wireless communication device are the same. If the selected protocol is the same as that of the wireless communication device, the program proceeds to step 184 where the wireless communication device establishes a wireless communication using its protocol and begins transmitting data.

However, if the selected protocol is inconsistent with that of the wireless communication device, the program proceeds to step 186, where the wireless communication device decodes at least a portion of the setup information of the wireless communication setup frame using the selected protocol. In the example, the wireless communication device obtains at least part of the decoded wireless communication setting information by decoding the header of the frame conforming to the original physical layer format, and when the header of the frame does not conform to the original physical layer format, it determines that the remaining frames conform to the original physical layer format. The protocol format of the wireless communication device, the wireless communication device then decodes the wireless communication setting information. Note that the original physical layer format includes at least one of IEEE802.11a and IEEE 802.11g, and the protocol of the wireless communication device here includes IEEE802.11n.

In another example, the wireless communication device obtains at least part of the decoded wireless communication setting information by decoding a frame header conforming to the format of the original specific medium access control layer (MAC). When the control layer (MAC) format is determined, the remaining frames are formatted according to the protocol of the wireless communication device, and the wireless communication device then decodes the wireless communication setting information. Note that the original physical layer format includes at least one of IEEE 802.11a, IEEE 802.11b and IEEE802.11g, and the protocol of the wireless communication device here includes IEEE 802.11n.

The program then proceeds to step 188, where the wireless communication device determines whether the remaining frames are of the same protocol as the wireless communication device based on the decoding of at least a portion of the wireless communication setup information. The program then branches from step 190 to 194 when the remaining frames and the protocol of the wireless communication device are the same, and branches to step 192 when not. At step 192 the wireless communication device ignores the frame. At step 194, the wireless communication device processes the remaining frames with the same protocol as the wireless communication device.

FIG. 28 is a logic diagram of a method for a wireless communication device to participate in multi-protocol wireless communication. The method begins at step 200, where the wireless communication device determines whether the selected protocol is the same as the protocol of the wireless communication device. The process then branches from step 202 to 204 when the selected protocol is the same as that of the wireless communication device, and to step 206 when they are not. At step 192 the wireless communication device ignores the frame. At step 204, the wireless communication device formats the setting information part and the data part of the same frame as the protocol. The wireless communication then starts sending frames.

However, if the selected protocol is inconsistent with the protocol of the wireless communication device, the program proceeds to step 206, where the wireless communication device formats at least a part of the setting information of the wireless communication device according to the selected protocol to generate the original formatted settings information. The program then proceeds to step 208, where the wireless communication device formats the rest of the setting information of the wireless communication device according to the protocol of the wireless communication device to generate the currently formatted setting information. The program then proceeds to step 210, where the wireless communication device formats the data according to the protocol of the wireless communication device to generate data in the current format. Refer to the formatting example in the preceding figure. The program then proceeds to step 212, where the wireless communication device transmits a frame containing the original formatted setup information, the currently formatted setup information and the currently formatted data.

In the example of the present invention, the preamble information should be backward compatible with the current 802.11 standard. The problem in TGn is how to operate inside the original 802.11a and 802.11b/g equipment. The internal operation here includes the following two situations:

- Same BSS: All devices communicate using the same application.

- Channel shifting/"overlapping" BSS

This can be achieved by either designing the PLCP header to allow an 802.11a/g STA to reassert CCA or using a protection mechanism such as RTS/self-CTS.

- 802.11g chooses the latter when dealing with 802.11b devices.

- To some extent, one can rely on RTS/CTS to protect symbol groups anyway.

For unchanged signal fields decoded at the legacy base station, it is highly desirable to use the same linearly weighted existing long training and signal symbols at the transmit antenna input. In MISO systems, the same weighting is applied to the first two long training symbols and to the original signal field for the decoding of the original base station.

In the example of M transmit antennas, N receive antennas and a sequence of L transmit symbols, Xk is the received signal on subcarrier k:

--------→

X _k ＝S _k ·H _k +N _k RX antennas

The zero forcing (ZF) MIMO channel estimate can then be calculated:

${\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; h</span>}}}_{\mathrm{<span\; class="notranslate">\; k</span>}}{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}^{\mathrm{<span\; class="notranslate">\; h</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; )</span>}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}^{\mathrm{<span\; class="notranslate">\; h</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}^{\mathrm{<span\; class="notranslate">\; h</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}$

If the long training symbol sequence has been defined (that is, Sk is finally a real scalar multiplied by an orthogonal matrix).

The minimum mean square error of the channel estimate can be calculated:

${\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; h</span>}}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}^{\mathrm{<span\; class="notranslate">\; h</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; \&eta;</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; I</span>}<span\; class="notranslate">\; )</span>}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}^{\mathrm{<span\; class="notranslate">\; h</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&rho;</span>}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}^{\mathrm{<span\; class="notranslate">\; h</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}$

$\mathrm{<span\; class="notranslate">\; \&rho;</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; I</span>}}{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; \&eta;</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}$

For simplicity, hk is assumed to be Gaussian error, and "reliable long training selection" is used. Note that the expressions for the least mean square estimate and the ZF estimate ignore the subsequent selection of the sequence, since S was chosen with care as shown earlier.

FIG. 29 is a descriptive diagram describing a transmission mode of the frame format in FIG. 7. FIG. For this transmission format, in order to meet backward compatibility and meet the requirements required for channel estimation of the next generation, W can simply select and apply W and W ⁻¹ . Also, any directional patterns [w11..w1M] produced by MIMO transmitters (next generation devices) should be well received by legacy 802.11a/g devices.

In this example, the signal detection (s _k ) 253 is multiplied by multiple weighting factors (W _{k, m} ) 301, 303, 305, where k is equal to the number of channel detections, from 1 to 1, and m is equal to the transmitting antenna 82- The number of 86. The weighted channel sounding is converted into an RF signal by transmitters 67,69,71 and continuously transmitted by antennas 81,83,85. In this example, the weighting factor matrix could be:

With all antennas transmitting at the same time, a null value is produced. Null values are compensated by choosing a weighting sequence. This weighted sequence acts as a form of orientation to steer nulls in a particular direction. For example, when the vector w1=[11] (a row of the previous sliding W matrix in the case of 2TX), the null values will be directed to the directions -90° and +90°, therefore, in the single-input receiver of the original WLAN equipment Certain directions are unfavorable relative to other directions.

According to the invention, a different complex weighting is used for each subcarrier of transmit antenna M-1. This forms a different directional pattern on each subcarrier and results in less power consumption and capacity loss in the worse direction. This is depicted in Figures 31 and 32.

FIG. 31 is a descriptive diagram depicting a method of forming preamble information of a frame in the format as in FIG. 7 of a next-generation MIMO transmitter and, in particular, of a two-antenna next-generation MIMO transmitter. In the figure, two preambles are generated: one for the active antenna. The first preamble 311 transmitted by the first antenna includes a double guard interval (GI2) 313, the first channel sounding (CS 0,0) 315, the second channel sounding (CS 0,1) 317 another Guard interval (GI) 323 and third channel sounding (CS 0,2) 321. The second preamble 327 transmitted through the second antenna includes a double guard interval (GI2) 329, a first channel sounding (CS 1,0) 331, a second channel sounding (CS 1,1) 333, a A guard interval (GI) 335, a signal field (SIG) 337, another guard interval (GI2) 339 and a third channel sounding (CS 1, 2) 341.

In this example, the following expressions will be used for the various channel soundings:

s ₁₁ =s ₀₀

${\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 10</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}{<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}}$

s ₁₁ =s ₁₀

s ₀₂ =s ₀₀

${\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}{<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}}$

From these channel soundings the following weighting factors will be applied:

${\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>\left[\begin{array}{cc}{\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 10</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="11"\; label="s"\; filenames="H05169625420050518E000111.png,H05169625420050518E000121.png"\; state="\{\{state\}\}">s</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}\\ {\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="20"\; label="s"\; filenames="H05169625420050518E000121.png"\; state="\{\{state\}\}">s</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 20</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}\end{array}\right]<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>\left[\begin{array}{cc}\mathrm{<span\; class="notranslate">\; 1</span>}& <span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}\\ \mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}\end{array}\right]<span\; class="notranslate">\; \&Center\; Dot;</span>\left[\begin{array}{cc}\mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 0</span>}\\ \mathrm{<span\; class="notranslate">\; 0</span>}& {\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}{<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}}\end{array}\right]$

$<span\; class="notranslate">\; =</span>\left[\begin{array}{cc}{\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}{<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}}\\ {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}{<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}}\end{array}\right]$

The first subscript number of the channel sounding is equal to the number of antennas. The second subscript number is equal to the number of symbols, and k is equal to the number of channel soundings. For example, s _{10, k} equals that the first symbol of the kth channel is transmitted on the first antenna.

To obtain a different directional pattern per subcarrier, the following equations apply:

FIG. 32 is a descriptive diagram depicting a method of preamble formation of a frame formatted as in FIG. 7 for a next-generation MIMO transmitter of three antennas. In the figure, three preambles are generated: one for each activated antenna. The first preamble 351 transmitted through the first antenna includes a double guard interval (GI2) 353, a first channel sounding (CS 0,0) 355, a second channel sounding (CS 0,1) 357, a guard interval (GI) 359, a signal field (SIG) 361, another guard interval (GI) 363, a third channel sounding (CS 0, 2) 365, a third guard interval (GI) 367 and a fourth Channel sounding CS 0,3)369. The second preamble 371 transmitted through the second antenna includes a double guard interval (GI2) 373, a first channel sounding (CS 1,0) 375, a second channel sounding (CS 1,1) 377, a guard interval (GI) 379, a signal field (SIG) 381, another guard interval (GI2) 383 and a third channel sounding (CS 1, 2) 385, a third guard interval (GI) 387 and a fourth Channel Sounding (CS 1, 3) 389. The third preamble 391 transmitted through the third antenna includes a double guard interval (GI2) 393, a first channel sounding (CS2, 0) 395, a second channel sounding (CS 2, 1) 397, a guard interval (GI) 399, a signal field (SIG) 401, another guard interval (GI2) 403 and a third channel sounding (CS 2, 2) 405, a third guard interval (GI) 407 and a fourth channel Probe (CS 2, 3) 409.

For various channel soundings, the following matrix of weighting factors can be used:

${\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>\left[\begin{array}{ccc}{\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 10</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="11"\; label="s"\; filenames="H05169625420050518E000111.png,H05169625420050518E000121.png"\; state="\{\{state\}\}">s</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}\\ {\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="20"\; label="s"\; filenames="H05169625420050518E000121.png"\; state="\{\{state\}\}">s</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 20</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}\\ {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 30</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 31</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 32</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}\end{array}\right]<span\; class="notranslate">\; =</span>\left[\begin{array}{ccc}{\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}{<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}{<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&phi;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}}\\ {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&pi;</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; )</span>}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&phi;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&pi;</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; )</span>}\\ {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&pi;</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; )</span>}& {\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&phi;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&pi;</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; )</span>}\end{array}\right]$

To obtain a different directional pattern per subcarrier, the following applies:

_θk = π·k/6

φ _k = π·(k+4)/6

In Figures 31 and 32, more signal energy is transmitted so that the receiver can get a better channel estimate. This makes for simpler ZF or MMSE channel estimation at Rx (majority addition/shift):

${\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; T</span>}}<span\; class="notranslate">\; =</span>\left[\begin{array}{cc}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}& <span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}\\ <span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}& <span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}\end{array}\right]<span\; class="notranslate">\; \&DoubleRightArrow;</span>{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; T</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}\left[\begin{array}{cc}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}& <span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}\\ <span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}& <span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}\end{array}\right]$

${\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; T</span>}}<span\; class="notranslate">\; =</span>\left(\begin{array}{ccc}\mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}\\ \mathrm{<span\; class="notranslate">\; 1</span>}& \frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt{\mathrm{<span\; class="notranslate">\; 3</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}& \frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt{\mathrm{<span\; class="notranslate">\; 3</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}\\ \mathrm{<span\; class="notranslate">\; 1</span>}& \frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt{\mathrm{<span\; class="notranslate">\; 3</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}& \frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt{\mathrm{<span\; class="notranslate">\; 3</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}\end{array}\right)<span\; class="notranslate">\; \&DoubleRightArrow;</span>{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; T</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>\left(\begin{array}{ccc}\mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}\\ \mathrm{<span\; class="notranslate">\; 1</span>}& \frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt{\mathrm{<span\; class="notranslate">\; 3</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}& \frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt{\mathrm{<span\; class="notranslate">\; 3</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}\\ \mathrm{<span\; class="notranslate">\; 1</span>}& \frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt{\mathrm{<span\; class="notranslate">\; 3</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}& \frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt{\mathrm{<span\; class="notranslate">\; 3</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}\end{array}\right)$

Channel estimation can be done by a priori knowledge of the orientation-forming coefficients of previous subcarriers, and these coefficients do not have to be applied on the remaining transmission symbols. Its advantage is that no extra multiplication is required at the transmitter, since the LTRN sequence can be easily looked up in a table.

The channel can be estimated without prior knowledge of the coefficients formed by the previous subcarrier orientation, and these coefficients should be applied on the remaining transmission symbols. It has the advantage that the receiver's channel estimation is simplified (fewer multiplications), but the transmitter performs additional multiplications.

In the first case, using the earlier notation and L=M:

${\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; h</span>}}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}^{\mathrm{<span\; class="notranslate">\; h</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; T</span>}}^{\mathrm{<span\; class="notranslate">\; h</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}$

${\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; diag</span>}<span\; class="notranslate">\; (</span>\left[\begin{array}{cccc}\mathrm{<span\; class="notranslate">\; 1</span>}& {\mathrm{<span\; class="notranslate">\; e</span>}}^{\frac{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="1"\; label="l"\; filenames="H05169625420050518E000031.png,H05169625420050518E000101.png"\; state="\{\{state\}\}">l</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{\mathrm{<span\; class="notranslate">\; 6</span>}}}& <span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span>& {\mathrm{<span\; class="notranslate">\; e</span>}}^{\frac{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}}{\mathrm{<span\; class="notranslate">\; 6</span>}}}\end{array}\right]<span\; class="notranslate">\; )</span>$

In the second case, using the earlier notation and L=M:

${\stackrel{<span\; class="notranslate">\; ^</span>}{\mathrm{<span\; class="notranslate">\; h</span>}}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; the\; s</span>}}_{\mathrm{<span\; class="notranslate">\; 00</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; T</span>}}^{\mathrm{<span\; class="notranslate">\; h</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}$

Note that the channel estimation can be further improved by replicating the entire length of the M-sequence p times. Improved by doing simple averaging. The overhead is the same as the single active transmitter approach described in slide 10, but the performance is superior.

In the case that the preamble information is backward compatible, the number of long training sequence symbols is M+1, and a longer sequence will include p*M+1 long training symbols. There are p groups of M symbols that are the same, and the first and second symbols on each antenna are the same.

Those of ordinary skill in the art will understand that the terms "substantially" or "approximately" herein provide industry-accepted tolerances. Industry allowed tolerances range from less than 1% to 20% and are equivalent to, but not limited to, component effects, integrated circuit process variation, temperature variation, rise and fall times and/or termination noise. Those of ordinary skill in the art should also understand that the "feasible connection" mentioned here includes direct connection and indirect connection through other components, parts, circuits or modules. Intervening parts, components, circuits or modules used for indirect connections do not change the signal's information but modulate its current, voltage and/or power. Those of ordinary skill in the art should also understand that an inferred connection (that is, a component is connected to another component by inference) includes a direct connection and an indirect connection between two components in the same manner as a "feasible connection". Those of ordinary skill in the art will also understand that a "positive comparison" as used herein means that a comparison between two or more components, products, signals, etc. provides a desired relationship. For example, when the desired relationship is that signal 1 has a greater magnitude than signal 2, a positive comparison is obtained when signal 1 has a greater magnitude than signal 2 or when signal 2 has a smaller magnitude than signal 1.

The foregoing discussion has presented various embodiments of wireless communications in a wireless communications system including a plurality of wireless communications devices of different protocols. Those of ordinary skill in the art will appreciate that other embodiments can be derived from the teachings of the present invention without departing from the scope of the claims.

Pursuant to 35USC §119, this patent application claims the priority of the following four pending patent applications: The first one is entitled Multi-protocol wireless communication system in wireless local area network, and the provisional application serial number is: 60/544,605, and the filing date is 2004 February 13; the name of the second item is wireless local area network for high-speed data transmission, the provisional application serial number is: 60/545,854, and the application date is February 19, 2004; the name of the third item is wireless communication system. Input and multiple output agreement, the provisional application serial number is: 60/568,914, the application date is May 7, 2004; the name of the fourth item is the same as the title of this patent application, the provisional application serial number is 60/573,782, the provisional application date for May 24, 2004.

Mode selection table:

Table 1: 2.4 GHz, 20/22 MHz channel BW, 54Mbps maximum bit rate

Encoding

Rate Modulation Rate NBPSC NCBPS NDBPS EVM Sensitivity ACR AACR

1 Barker BPSK

2 Barker QPSK

5.5 CCK

6 BPSK 0.5 1 48 24 -5 -82 16 32

9 BPSK 0.75 1 48 36 -8 -81 15 31

11 CCK

12 QPSK 0.5 2 96 48 -10 -79 13 29

18 QPSK 0.75 2 96 72 -13 -77 11 27

24 16-QAM 0.5 4 192 96 -16 -74 8 24

36 16-QAM 0.75 4 192 144 -19 -70 4 20

48 64-QAM 0.666 6 288 192 -22 -66 0 16

54 64-QAM 0.75 6 288 216 -25 -65 -1 15

Table 2: Multiplexing of Table 1

Channel Frequency (MHz)

1 2412

2 2417

3 2422

4 2427

5 2432

6 2437

7 2442

8 2447

9 2452

10 2457

11 2462

12 2467

Table 3: Power Spectrum Plot (PSD) mask of Table 1

PSD mask 1

Frequency Offset dBr

-9MHz to 9MHz 0

+/-11MHz -20

+/-20MHz -28

+/-30MHz and greater -50

Table 4: 5GHz, 20MHz channel BW, 54Mbps maximum bit rate

Encoding

Rate Modulation Rate NBPSC NCBPS NDBPS EVM Sensitivity ACR AACR

6 BPSK 0.5 1 48 24 -5 -82 16 32

9 BPSK 0.75 1 48 36 -8 -81 15 31

12 QPSK 0.5 2 96 48 -10 -79 13 29

18 QPSK 0.75 2 96 72 -13 -77 11 27

24 16-QAM 0.5 4 192 96 -16 -74 8 24

36 16-QAM 0.75 4 192 144 -19 -70 4 20

48 64-QAM 0.666 6 288 192 -22 -66 0 16

54 64-QAM 0.75 6 288 216 -25 -65 -1 15

Figure 5: Multiplexing of Table 4

Frequency

Channel (MHz) Country Channel Frequency (MHz) Country

240 4920 Japan

244 4940 Japan

248 4960 Japan

252 4980 Japan

8 5040 Japan

12 5060 Japan

16 5080 Japan

36 5180 US/Europe 34 5170 Japan

40 5200 US/Europe 38 5190 Japan

44 5220 US/Europe 42 5210 Japan

48 5240 US/Europe 46 5230 Japan

52 5260 US/Europe

56 5280 US/Europe

60 5300 US/Europe

64 5320 US/Europe

100 5500 US/Europe

104 5520 US/Europe

108 5540 US/Europe

112 5560 US/Europe

116 5580 US/Europe

120 5600 US/Europe

124 5620 US/Europe

128 5640 US/Europe

132 5660 US/Europe

136 5680 US/Europe

140 5700 US/Europe

149 5745 United States

153 5765 United States

157 5785 United States

161 5805 United States

165 5825 United States

Table 6: 2.4GHz, 20MHz channel BW, 192Mbps maximum bit rate

ST coding

Rate TX Antenna Rate Modulation Coding Rate NBPSC NCBPS NDBPS

12 2 1 1 BPSK 0.5 1 48 24

24 2 1 1 QPSK 0.5 2 96 48

48 2 1 16-QAM 0.5 4 192 96

96 2 1 64-QAM 0.666 6 288 192

108 2 1 64-QAM 0.75 6 288 216

18 3 1 1 BPSK 0.5 1 48 24

36 3 1 1 QPSK 0.5 2 96 48

72 3 1 16-QAM 0.5 4 192 96

144 3 1 64-QAM 0.666 6 288 192

162 3 1 64-QAM 0.75 6 288 216

24 4 1 1 BPSK 0.5 1 48 24

48 4 1 QPSK 0.5 2 96 48

96 4 1 16-QAM 0.5 4 192 96

192 4 1 64-QAM 0.666 6 288 192

216 4 1 64-QAM 0.75 6 288 216

Figure 7: Multiplexing of Table 6

Channel Frequency (MHz)

1 2412

2 2417

3 2422

4 2427

5 2432

6 2437

7 2442

8 2447

9 2452

10 2457

11 2462

12 2467

Table 8: 5GHz, 20MHz channel BW, 192Mbps maximum bit rate

ST coding

Rate TX Antenna Rate Modulation Coding Rate NBPSC NCBPS NDBPS

12 2 1 1 BPSK 0.5 1 48 24

24 2 1 1 QPSK 0.5 2 96 48

48 2 1 16-QAM 0.5 4 192 96

96 2 1 64-QAM 0.666 6 288 192

108 2 1 64-QAM 0.75 6 288 216

18 3 1 1 BPSK 0.5 1 48 24

36 3 1 1 QPSK 0.5 2 96 48

72 3 1 16-QAM 0.5 4 192 96

144 3 1 64-QAM 0.666 6 288 192

162 3 1 64-QAM 0.75 6 288 216

24 4 1 1 BPSK 0.5 1 48 24

48 4 1 1 QPSK 0.5 2 96 48

96 4 1 16-QAM 0.5 4 192 96

192 4 1 64-QAM 0.666 6 288 192

216 4 1 64-QAM 0.75 6 288 216

Figure 9: Multiplexing of Table 8

frequency

Channel (MHz) Country Channel Frequency (MHz) Country

240 4920 Japan

244 4940 Japan

248 4960 Japan

252 4980 Japan

8 5040 Japan

12 5060 Japan

16 5080 Japan

36 5180 US/Europe 34 5170 Japan

40 5200 US/Europe 38 5190 Japan

44 5220 US/Europe 42 5210 Japan

48 5240 US/Europe 46 5230 Japan

52 5260 US/Europe

56 5280 US/Europe

60 5300 US/Europe

64 5320 US/Europe

100 5500 US/Europe

104 5520 US/Europe

108 5540 US/Europe

112 5560 US/Europe

116 5580 US/Europe

120 5600 US/Europe

124 5620 US/Europe

128 5640 US/Europe

132 5660 US/Europe

136 5680 US/Europe

140 5700 US/Europe

149 5745 United States

153 5765 United States

157 5785 United States

161 5805 United States

165 5825 United States

Table 10: 5GHz, 40MHz channel and maximum bit rate of 486Mbps

ST coding

Rate TX Antenna Rate Modulation Coding Rate NBPSC

13.5Mbps 1 1 1 BPSK 0.5 1

27Mbps 1 1 1 QPSK 0.5 2

54Mbps 1 1 16-QAM 0.5 4

108Mbps 1 1 64-QAM 0.666 6

121.5Mbps 1 1 64-QAM 0.75 6

27Mbps 2 1   BPSK 0.5 1

54Mbps 2 1 qpsk 0.5 2

108Mbps 2 1 16-QAM 0.5 4

216Mbps 2 1 64-QAM 0.666 6

243Mbps 2 1 64-QAM 0.75 6

40.5Mbps 3 1 BPSK 0.5 1

81Mbps 3 1 qpsk 0.5 2

162Mbps 3 1 16-QAM 0.5 4

324Mbps 3 1 64-QAM 0.666 6

365.5Mbps 3 1 64-QAM 0.75 6

54Mbps 4 1 BPSK 0.5 1

108Mbps 4 1 qpsk 0.5 2

216Mbps 4 1 16-QAM 0.5 4

432Mbps 4 1 64-QAM 0.666 6

486Mbps 4 1 64-QAM 0.75 6

Table 11: Power Spectrum Plot (PSD) mask for Table 10

PSD mask 2

Frequency offset dBr

-19MHz to 19MHz 0

+/-21MHz -20

+/-30MHz -28

+/-40MHz and greater -50

Figure 12: Multiplexing of Table 10

Frequency Frequency

Channel (MHz) Country Channel (MHz) Country

242 4930 Japan

250 4970 Japan

12 5060 Japan

38 5190 US/Europe 36 5180 Japan

46 5230 US/Europe 44 5520 Japan

54 5270 US/Europe

62 5310 US/Europe

102 5510 US/Europe

110 5550 US/Europe

118 5590 US/Europe

126 5630 US/Europe

134 5670 US/Europe

151 5755 United States

159 5795 United States

Claims (10)

1. A method for the leading information of a frame generated by a multiple-input multiple-output MIMO wireless communication system, is characterized in that the method comprises: For each transmitting antenna of the MIMO wireless communication system, a short training sequence according to the old version of the 802.11 standard protocol is generated, wherein, for each transmitting antenna, the short training sequence is based on the number of transmitting antennas and the short training sequence The duration is cyclically shifted; For each transmit antenna in the first group of transmit antennas of the MIMO wireless communication system, at least one long training sequence is generated after the short training sequence, and the at least one long training sequence includes a pre-first guard interval, wherein For each transmit antenna in the first set of transmit antennas, the at least one long training sequence is cyclically shifted; For each transmit antenna except the first group of transmit antennas of the MIMO wireless communication system, at least one supplementary long training sequence is generated, wherein for each of the other transmit antennas, the at least one supplementary long training sequence is cyclically shifted bits, and the first guard interval is prior to the at least one supplementary long training sequence. 2. The method according to claim 1, further comprising: for each transmit antenna of the first group of transmit antennas of the MIMO wireless communication system, generating a second long training sequence after the at least one long training sequence a guard interval; and generating a signal field after the second guard interval. 3. The method according to claim 2, further comprising: for each transmit antenna in the MIMO wireless communication system except the first group of transmit antennas, in the at least one supplementary long training sequence Then generate a third guard interval, wherein the duration of the first guard interval and the third guard interval is longer than that of the second guard interval. 4. The method according to claim 1, wherein when the MIMO wireless communication system includes three transmit antennas, the method further comprises: For the first and second transmit antennas among the three transmit antennas, generate the first and second long training sequences according to the old version of the 802.11 standard as the at least one long training sequence, wherein the first and the second long training sequence is cyclically shifted respectively; and For a third transmit antenna among the three transmit antennas, generate a third long training sequence according to an old version protocol of the 802.11 standard as the at least one supplementary long training sequence. 5. A method for generating the preamble information of a frame compatible with devices adopting an old version of the 802.11 standard protocol in a MIMO wireless communication system, characterized in that the method comprises: For each of the multiple transmit antennas of the MIMO wireless communication system, a short training sequence based on the old version of the 802.11 standard protocol is generated, wherein, for each transmit antenna, the short training sequence is based on the number of transmit antennas and the duration of said short training sequence are cyclically shifted; For the first transmitting antenna among the plurality of transmitting antennas, a first guard interval is generated after the short training sequence, a first long training sequence is generated after the first guard interval, and a first long training sequence is generated after the first long training sequence Then generate the second longest training sequence; For each transmit antenna except the first transmit antenna among the multiple transmit antennas, a supplementary long training sequence is generated respectively, where the supplementary long training sequence includes a second guard interval and two specific long training sequences. 6. The method of claim 5, wherein the supplementary long training sequence for each of the plurality of transmit antennas except the first transmit antenna is cyclically shifted respectively. 7. A radio frequency transmitter, characterized in that the radio frequency transmitter comprises: a baseband processing module, which converts the output data into an output symbol stream through the feasible connection; A transmitter part, which converts the output symbol stream into an output radio frequency signal through a feasible connection, wherein the baseband processing module is used for: For each transmitting antenna of the transmitter part, a short training sequence according to the old version of the 802.11 standard protocol is generated, wherein, for each transmitting antenna, the short training sequence is based on the number of transmitting antennas and the duration of the short training sequence The time is cyclically shifted; For each transmit antenna in the first group of transmit antennas of the transmitter part, at least one long training sequence is generated after the short training sequence, and the at least one long training sequence includes a first guard interval in advance, wherein for for each transmit antenna in the first set of transmit antennas, the at least one long training sequence is cyclically shifted; generating at least one supplementary long training sequence for each transmit antenna except the first set of transmit antennas in the transmitter part, wherein for each of the other transmit antennas, the at least one supplementary long training sequence is cyclically shifted , and the first guard interval is prior to the at least one supplementary long training sequence. 8. The radio frequency transmitter as claimed in claim 7, wherein, for each transmitting antenna of the first group of transmitting antennas of the transmitter part, the baseband processing module is also applied to: generating a second guard interval after the at least one long training sequence; A signal field is generated after the second guard interval. 9. A radio frequency transmitter, characterized in that the radio frequency transmitter comprises: a baseband processing module, which converts the output data into an output symbol stream through the feasible connection; A transmitter part, which converts the output symbol stream into an output radio frequency signal through a feasible connection, wherein the baseband processing module is used for: For each transmitting antenna in the plurality of transmitting antennas of the transmitter part, a short training sequence according to the old version of the 802.11 standard protocol is generated, wherein, for each transmitting antenna, the short training sequence is based on the number of transmitting antennas and The duration of the short training sequence is cyclically shifted; For the first transmitting antenna among the plurality of transmitting antennas, a first guard interval is generated after the short training sequence, a first long training sequence is generated after the first guard interval, and a first long training sequence is generated after the first long training sequence Then generate the second longest training sequence; For each transmit antenna except the first transmit antenna among the multiple transmit antennas, a supplementary long training sequence is generated respectively, where the supplementary long training sequence includes a second guard interval and two specific long training sequences. 10. The radio frequency transmitter according to claim 9, wherein the baseband processing module is further used for: The supplementary long training sequence for each of the multiple transmit antennas except the first transmit antenna is cyclically shifted respectively.

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