MX2007000218A - Method and apparatus for transmitting data with down compatibility in high throughput wireless network - Google Patents

Abstract

A method and an apparatus are provided for enabling a legacy station to perform virtual carrier sensing when a plurality of stations with heterogeneous capabilities coexist in a wireless network. The method includes receiving first data via a bonded channel formed by channel bonding first and second adjacent channels, and transmitting second data via each of the first and second adjacent channels, the second data being a clear-to-send (CTS) frame or a request-to-send (RTS) frame.

Description

METHOD AND DEVICE FOR TRANSMITTING DATA WITH COMPATIBILITY WITH PREVIOUS VERSIONS IN WIRELESS NETWORKS HIGH PERFOMANCE FIELD OF THE INVENTION The methods and devices consistent with the present invention relate to the transmission and reception of data in an inherited format in a high-performance wireless network. BACKGROUND OF THE INVENTION Recently there has been an increasing demand for ultra high-speed communication networks due to the widespread public use of the Internet and a rapid increase in the amount of multimedia data available. Since local area networks (LANs) emerged in the late 1980s, the speed of data transmission over the Internet has increased dramatically, from 1 Mbps to approximately 100 Mbps. Consequently, high-speed Ethernet transmission has gained popularity and widespread use. Currently, intensive investigations of Ethernet networks with gigabit speeds are underway. A growing interest in wireless network connections and communications has initiated research and development of wireless LAN (WLAN), and has greatly increased the availability of WLAN networks to the consumer. Although the REF .: 178029 use of WLAN networks could reduce performance due to lower transmission speed and little stability compared to wired LANs, WLAN networks have several advantages, including the ability to build wireless networks, increased mobility, and so on. Consequently, markets for WLAN networks have grown gradually. Due to the need for a higher transmission speed and the development of wireless transmission technologies, the initial standard of the Institute of Electrical and Electronic Engineering (IEEE) 802.11, which specifies a transfer speed of 1 to 2 Mbps, has evolved to advanced standards, including the IEEE 802.11a, 802.11b and 802. llg standards. The IEEE 802. llg standard, which uses a transmission speed of 6 to 54 Mbps in the National Infrastructure Information Infrastructure (NII) 5 GHz, makes use of orthogonal multiplexing frequency division (OFDM) as its transmission technology. With the public's growing interest in OFDM transmission and the use of a 5 GHz band, much more attention has been paid to the IEEE 802. llg standard and OFDM transmission technology - than to other wireless communication standards. Recently, the company Kor-ea Telecommunication (KT) Corporation of Korea has launched and offered wireless Internet services using WLAN networks, known as "Nespot". Nespot services allow Internet access using WLANs in accordance with the IEEE 802.11b standard, commonly known as Wi-Fi (wireless fidelity). The communication standards for wireless data communication systems, which have been completed and promulgated, or which are being investigated and discussed, include Wide Code Division Multiple Access (WCDMA), IEEE 802. llx, Bluetooth, IEEE 802.15.3, etc. ., which are known as third generation communication (3G) standards. The most widely known and economic standard of wireless data communication is IEEE 802.11b, a series of IEEE 802. llx. An IEEE 802.11b standard for WLAN networks provides data transmission at a maximum speed of 11 Mbps, and uses the Industrial, Scientific and Medical (ISM) 2.4 GHz band, which can be used below a predetermined electric field without the need for authorization. With the recent widespread use of the IEEE 802.11a standard for WLAN networks, which provides a maximum data rate of 54 Mbps in the 5 GHz band using OFDM, IEEE 802.11g was developed as an extension of the IEEE 802.11a standard for data transmission in the 2.4 GHz band using OFDM, and it is being intensively investigated. Ethernet and WLAN networks, which are currently widely used, use a Multiple Access by Carrier Detection (CSMA) method. According to the CSMA method, determines if a channel is in use. If the channel is not in use, that is, if the channel is inactive, then data is transmitted. If the channel is busy, an attempt is made to retransmit the data after a predetermined lapse. A Multiple Carrier Detection Access method with collision detection (CSMA / CD), which is a refinement of the CSMA method, is used in a wired LAN, while a Carrier Detection Multiple Access method is used. collision avoidance (CSMA / CA) in wireless data communications. In the CSMA / CD method, a station suspends signal transmission if a collision is detected during transmission. Compared to the CSMA method, which pre-checks whether a channel is busy before transmitting data, in the CSMA / CD method, the station suspends signal transmission when a collision is detected during signal transmission, and transmits a jam signal to another station to inform him of the occurrence of the collision. After transmission of the jam signal, the station has a random interruption period to delay and restart signal transmission. In the CSMA / CD method, the station does not transmit data immediately, even after the channel is inactive, and has a random interruption period of a predetermined duration before transmission to avoid signal collision. Yes a signal collision occurs during transmission, the duration of the random interruption period is doubled, thereby further reducing the probability of a collision. The CSMA / CA method is classified as physical carrier detection and virtual carrier detection. Physical carrier detection refers to the physical detection of active signals in the wireless medium. The virtual carrier detection is performed in such a way that the information about the duration of the occupation of a medium is fixed to a data unit of media access control protocol (MAC) / physical unit (PHY) of service data of data (MPDU / PSDU), and then the data transmission starts after the estimated duration has elapsed. However, if the MPDU / PSDU can not be interpreted, the virtual carrier detection mechanism can not be adopted. IEEE 802.11? It provides coverage for IEEE 802.11a networks at 5 GHz and IEEE 802. llg networks at 2.4 GHz, and allows stations of diverse data speeds to coexist. To operate the stations of various data rates using the CSMA / CA method, the stations must interpret MPDU / PSDU. However, some stations, that is, legacy data stations, can often not process data transmitted or received at high speeds.

In this case, the legacy data stations can not perform a virtual carrier detection. Figure 1 is a data structure of a related technique format of the Data Protocol Unit (PPDU) of Physical Layer Convergence Procedure (PLCP) as defined in the IEEE 802.11a protocol. The PPDU includes a PLCP header and a Physical Capability Service Data Unit (PSDU). A data rate field 3 and a data length field 4 are also used to determine a length of a data field that follows the PLCP header of the PPDU. The data rate field 3 and the data length field 4 are also used to determine the time of the data that is received or transmitted, thereby performing a virtual-carrier detection. In addition, if a Message Protocol Data Unit (MPDU) of the received PPDU is accurately filtered, a "Dur / ID" field is interpreted, which is a field between the header fields of the MPDU, and it is virtually determined that the medium is occupied during an expected period of use of the medium. In the event that a preamble field and a signal field of a received PPDU frame are misinterpreted, the means may attempt to transmit data by an interruption in a predetermined Interframe Extended Space (EIFS), which is longer than a Space Between Frames (DIFS) of a Coordination Function Distributed (DCF), so uniformity in access to the media of all stations available in the DCF is not ensured. In a network in which a station using a conventional protocol or an inherited data station and a High Performance (HT) station coexist, the legacy data station can be updated for the transmission and reception of HT data. However, an inherited data station or a conventional station can not perform a virtual carrier detection because these stations can not interpret the "Dur / ID" field present in the data transmitted and received by the HT station. TECHNICAL PROBLEM Figure 2 is a diagram illustrating that a legacy low rate data station is unable to perform virtual carrier detection when a plurality of stations coexist with a variety of transmission capabilities. A high-performance station on the transmitter side (abbreviated as HT STA on the transmitter side) 101 is a station that complies with the IEEE 802.11 ?, protocols and operates using a multi-input and multiple-output (MIMO) channel-joining technique. The union-of-channels is a mechanism by which data frames are transmitted through two adjacent channels. In other words, and according to a channel joining technique, since two adjacent channels are joined during data transmission, there is channel extension. The MIMO technique is a type of adaptable array antenna technology that electrically controls the addressability using a plurality of antennas. Specifically, in a MIMO system, addressability is increased using a plurality of antennas by reducing a beam width, thereby forming a plurality of transmission paths that are independent of each other. Therefore, the data transmission speed of a device that adopts the MIMO system is increased as many times as the number of antennas in a MIMO system. In this regard, when transmitting or receiving data using the junction of channels or MIMO technique, capable stations can read the transmitted or received data, but the incapable stations, ie the legacy data stations, can not read the transmitted data or received. The physical carrier detection allows a physical layer to inform a MAC layer whether a channel is busy or inactive by detecting whether the physical layer has received a predetermined level of reception power. Therefore, physical carrier detection is not associated with the interpretation of transmitted and received data. If the HT STA on the transmitter side 101 transmits HT data, an HT STA of the receiver side 102 receives the HT data and transmits an HT confirmation (Ack) to the HT STA of the transmitter side 101 in response to the received HT data. An additional HT STA 103 is capable of interpreting the HT data and the HT Ack. Assuming a duration in which the HT and Ack HT data is transmitted and received, which is set to a Network Assignment Vector (NAV), the medium is considered to be busy. Then, the additional HT STA 103 waits for a DIFS after a lapse of NAV, and then performs a random interruption, and finally transmits data. Meanwhile, an inherited data station 201 is a station that complies with the IEEE 802.11a, 802.11b or 802. llg protocols, but is unable to interpret HT data. Accordingly, after checking a duration of the Ack HT by physical carrier detection, the legacy data station 201 waits during the course of an EIFS and then performs an interrupt. In this way, the legacy data station 201 expects more than other stations, that is, the HT STA of the transmitter side 101, the HT STA of the receiving side 102 and the additional HT STA 103, before being assigned a means, thereby the efficiency of data transmission is adversely affected. The IEEE 802.11 standard specifies a response control box, such as an ACK, Request for Sending (RTS) or Free for Sending (CTS) box, which is transmitted to it data rate than the directly preceding box. However, if the control response box can not be transmitted at the same data rate as the directly preceding box, it must be transmitted at a higher speed in a number of basic services (BSS), as specified in the IEEE 802.11 standard. In addition, and unlike the data of inherited format, the HT data have HT preamble and HT signal fields added, which causes an increase in the costs of a PPDU, which can cause the ACK box to have a damaged operation in comparison to the inherited PPDU format. That is, the duration of the PPDU of the legacy format that complies with the IEEE 802.11a standard is approximately 20 μe, while the duration of a newly defined HT PPDU is 40 or more. TECHNICAL SOLUTION Consequently, there is a need to improve the operation of the use of networks by transmitting data of inherited format, that is, an ACK box, without a HT preamble, when an inherited data station can not interpret data transmitted from an HT station, which can prevent the virtual carrier detection from occurring properly. The present invention provides a method and device for allowing a low capacity station to perform a virtual carrier detection when it coexists a plurality of stations with heterogeneous capabilities in a wireless network. BRIEF DESCRIPTION OF THE INVENTION The present invention also provides a method and device for transmitting short data to obtain a high efficiency. In accordance with one aspect of the present invention, a method is provided for transmitting data over a wireless network, where the method comprises accessing a wireless network, receiving the first data using channel joining, the first data transmitted from a station that accessed to the wireless network, and transmitting second data to the respective channels associated with the joining of channels, where the second data is a free box for sending (CTS) or request for sending (RTS). In accordance with another aspect of the present invention, there is provided a wireless network device comprising a receiving unit that accesses a wireless network and receives first data transmitted from a -station that accessed the wireless network using union of channels, and a transmitting unit that transmits second data to channels associated with the joining of channels, where the second data is a free box for sending (CTS) or request for sending (RTS). BRIEF DESCRIPTION OF THE FIGURES These and other aspects of the present invention are they will become more apparent by the detailed description of exemplary embodiments, with reference to the appended figures, in which: Figure 1 is a schematic diagram of a PPDU format of the related art, as defined in the IEEE 802.11 protocol. Figure 2 is a diagram illustrating that an inherited data station with low transmission speed is unable to perform virtual carrier detection when a plurality of stations coexist with a variety of transmission capabilities. Figure 3 is a diagram illustrating a method for transmitting a response frame, in accordance with an exemplary embodiment of the present invention. Figures 4A and 4B are diagrams illustrating data structures of a PPDU transmitted and received by an HT station. Figure 5 is a diagram showing a method in which a receiving unit transmits a legacy data response frame when a transmitting unit transmits HT data using channel joining in accordance with an exemplary embodiment of the present invention. Figure 6 is a diagram showing a procedure in which a receiving unit transmits a Legacy data response box when a transmitting unit transmits HT data using union of channels in accordance with another exemplary embodiment of the present invention. Figure 7 is a diagram showing a method in which a receiving unit transmits a legacy data response frame when the transmitting unit transmits HT data without using channel joining. Figure 8 is a schematic illustrating a transmitting data station HT of inherited format according to an embodiment of the present invention. Figure 9 is a flow chart illustrating a procedure by which an HT station receives an HT box and transmits a legacy data box as a response box, in accordance with one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION The present invention, and the methods for obtaining it, may be more readily understood by reference to the following detailed description of the exemplary embodiments and the appended figures. However, the present invention may have many other forms and modalities, and shall not be construed as limited to the exemplary embodiments described herein. Rather, these exemplary modalities are provided so that the present disclosure is detailed and complete, and fully describes the concept of the present invention to those skilled in the art, and the present invention will be defined solely by the appended claims. Similar reference numbers refer to similar elements throughout the specification. Next, a method and device for transmitting and receiving data of inherited format in an HT wireless network will be described, with reference to illustrations of method flow diagrams, in accordance with exemplary embodiments of the present invention. It will be understood that each block of the illustrations of the flowchart, and the combinations of blocks in the illustrations of the flowchart, can be applied by instructions of computer programs. These instructions of computer programs can be provided to a processor of a general purpose computer, of special purposes, or any other programmable data processing device to produce a machine, so that the instructions, which are executed by the processor of The computer or other programmable data processing device creates ways to apply the functions specified in the blocks of the flowchart. These computer program instructions they can also be stored in a usable or readable memory for a computer, which can direct a computer, or other programmable data processing device, to operate in a particular way, so that the instructions stored in usable or readable memory A computer produces a production article that includes forms of instruction that apply the function specified in the blocks of the flowchart. Computer program instructions may also be loaded onto a computer or other programmable data processing device to cause a series of operational steps to be carried out on the computer or other programmable data processing device to produce a process performed by a computer. computer, so that instructions that run on the computer or other programmable device provide steps to apply the functions specified in the flowchart blocks. Each block of the flowchart illustrations may represent a module, segment or portion of code, comprising one or more executable instructions for applying the specified logic functions. It should also be noted that in some alternative applications, the functions that appear in the blocks may occur in another order. For example, two successive blocks can be executed essentially concurrently, or the blocks it can sometimes be executed in the reverse order, depending on the functionality involved. HT wireless networks in accordance with exemplary embodiments of the present invention include wireless networks capable of transmitting and receiving HT data, i.e., a wireless HT network that complies with the IEEE 802.11? Protocol, a wireless network having compatibility with one of the legacy format standards IEEE 802.11a, 802.11b, and 802. llg, and so on. Figure 3 is a diagram illustrating a method for transmitting a response frame in accordance with an exemplary embodiment of the present invention. Referring to Figure 3, an HT STA on the transmitting side 101, an HT STA on the receiving side 102, an additional HT STA 103, and an inherited data station 201 exist in a wireless network. In step S10, the HT STA on the transmitting side 101 transmits HT data to the HT STA on the receiving side 102. As indicated above, the HT data is transmitted at high speed using a channel junction or MIMO technique. HT stations include stations that allow a high speed of data transmission, that is, stations that comply with the IEEE 802.11 ?. Since the HT STA of the receiving side 102 and the additional HT STA 103 can interpret HT data, they can perform virtual carrier detection. However, and since the legacy data station 201 is not capable of interpreting HT data, it can not perform a virtual carrier detection. Instead, the legacy data station determines that a medium is currently busy, thus performing a physical carrier detection. After completion of the HT data transmission, the operation Sil is started and the legacy data station 201 waits during the course of an EIFS before performing the interrupt. If the HT STA of the transmitting side 101 completes the transmission of the HT data, the procedure passes to the operation Sil. At this time, the HT STA of the receiver side 102 transmits an Ack of inherited data after the passage of a short space between frames (SIFS) to the HT STA of the transmitter side 101. The Ack of inherited data is a response box generated from compliance with the IEEE 802.11a, 802.11b or 802. llg protocols. The Ack of inherited data can be transmitted and received from both an inherited data station and an HT station. After receiving each Ack of inherited data, each of the HT stations 101, 102, and 103 capable of interpreting a legacy data response box goes to operation S12 after the course of a DIFS, and then performs an interrupt procedure. Further, since the legacy data station 201 is able to interpret an Ack frame of legacy data but is unable to interpret HT data, it is it allows to wait during the course of the DIFS in operation S12 to prohibit the legacy data station 201 from performing the interruption procedure. Accordingly, the legacy data station 201 is able to participate in the interruption procedure as well as the HT 101, 102, and 103 stations, thus preventing deterioration of operation. Figures 4A and 4B are diagrams illustrating a data structure of a PPDU transmitted and received by an HT Station. The HT station allows the transmission and reception of data in two ways, where both are started with legacy data preambles, so that a legacy data station can interpret the data transmitted and received by the HT station with the legacy data preamble. As shown in Figure 4A, a legacy format PPDU 30 includes a preamble of legacy data including a Short Legacy Data Training Field (L-STF), a Long Legacy Data Training Field (L-LTF) and a Legacy Data Signal Field (L-SIG), and a load of Inherited Data (DATA). Similar to Figure 1, the L-SIG includes RATE, Reserved, LENGTH, and Parity fields. The legacy format PPDU 30 has the DATA loading following the L-STF, L-LTF, L-SIG fields that contain information related to power handling, signals and so on. Thus, the inherited format PPDU 30 can be interpreted by an HT station and by an inherited data station. As shown in Figure 4B, when a PPDU 40 has an HT preamble added to a legacy data preamble, the HT station considers the PPDU 40 as HT data. The HT preamble contains information related to HT data. The preamble HT consists of a HT signal field (HT-SIG), a short HT training field (HT-STF), and a long HT training field (HT-LTF). In detail, the HT-SIG consists of multiple fields including a LENGTH field that defines a HT data duration, a CS field that defines modulation and coding schemes, an advanced coding field that specifies the presence of advanced coding, a field of probe packet indicating whether transmission was performed on all antennas, a HT-LTF number field specifying the HT-LTF number in a transmitted PPDU, a short GI field specifying a short guard interval in a region of data of a frame, a Scrambler INIT field that specifies an initial value of an encoder, 20/40, which indicates whether the PPDU is converting to a signal at a bandwidth of 20 or 40 Hz, a CRC field for verification of errors, and a final field. As shown in Figure 4B, HT-SIG, HT-STF, HT-SIG, ..., HT-LTF, each contain a specific number of bits, followed by HT data. As shown in Figure 4B, if short data is transmitted on the HT PPDU 40, a considerable increase in the HT preamble is caused, thereby significantly increasing costs. Thus, in order to transmit frames that include only short data, ie, Ack or control boxes, it is efficient to use the inherited data PPDU 30. In addition, the inherited data PPDU 30 allows an inherited data station to perform the detection of virtual carrier when there is a legacy data station in a wireless network. Figure 5 is a diagram showing a method in which a receiving unit transmits a legacy data response frame when a transmitting unit transmits HT data using channel joining in accordance with an exemplary embodiment of the present invention. When a transmitting unit selects two channels adjacent to a channel in use, ie the channel in use and a directly next or directly preceding channel and the channel in use, linked together, and transmits them to a receiving unit, the receiving unit it receives them and transmits an Ack of inherited data to each channel. Figure 6 is a diagram showing a procedure in which a receiving unit transmits a Legacy data response box when a transmitting unit transmits HT data using the junction of channels in accordance with another exemplary embodiment of the present invention, wherein the antennas 181 and 182 transmit data to different channels, unlike Figure 5. When the transmitting unit selects two channels adjacent to a channel in use, ie, the channel in use and a directly next or directly preceding channel and the channel in use, linked together, and transmits them to a receiving unit, the receiving unit it receives them and transmits an Ack of inherited data to each channel. Unlike Figure 5, the respective antennas 181 and 182 are capable of handling different channels. The receiving unit accesses lower and higher sub-channels using the respective antennas 181 and 182, and transmits the same Ack table of inherited data 300. The structure of an inherited format frame is the same as that described in Figure 4. Legacy format data is transmitted simultaneously to a control channel and an extension channel in response to a frame transmitted using channel joining, as shown in Figures 5 and 6, which allow the legacy format data to also be received by stations on the extension channel. Figure 7 is a diagram showing a procedure in which a HT station on the receiving side transmits a legacy data response frame when the HT station on the transmitting side transmits HT data using a MIMD technique in accordance with an exemplary embodiment of the present invention. When the HT station on the transmitting side transmits HT data using a MIMO technique, the HT station on the receiving side uses an antenna 181 to transmit a legacy data response box via a channel in use. The HT station on the transmitting side is capable of receiving the response table of inherited data received by the channel in use. Other HT stations can interpret the legacy data response box to allow virtual carrier detection. In addition, legacy data stations that communicate over the channel in use can also interpret the legacy data response box to allow virtual carrier detection. The structure of an inherited format table is the same as that described in Figure 4A. As illustrated in Figures 5 to 7, the HT STA of the receiver side 102 transmits the PPDU of inherited data 30 in various ways, in accordance with the transmission method used by the HT STA of the transmitter side 101. The HT STA of the side receiver 102 may be informed of the transmission method used by the HT STA on the transmitter side 101 from MCS values in the HT-SIG field of the HT PPDU shown in Figure 4B. That is, the number of antennas used in data transmission or the number of spatial currents, modulation schemes used, coding speed, guard interval, and the use or non-use of union of channels (40 MHz) can be derived from the MCS values listed in the following Table. Table 1 illustrates an exemplary modulation and coding scheme (MCS) table. Table 1 An HT station can transmit not only the Ack box but also a PPDU of a control box, including short data such as a CTS or RTS box. During the transmission of the legacy format, it is not necessary to add a HT preamble to the data, an inherited data station can perform virtual carrier detection, with which costs are reduced. In case of a considerable amount of data, a PPDU of HT format is transmitted. In the case of short data, ie a small amount of data, for example a control box, a PPDU of inherited format is transmitted, thereby reducing a total amount of data transmitted and received in the wireless network in general and applying a wireless network where an HT station and an inherited data station coexist. The term "unit", as used herein, means, without being limited thereto, a software or hardware component or module, such as a Series of Programmable Field Ports (FPGA) or Application Specific Integrated Circuit (ASIC). ), which carries out certain tasks. A unit can be advantageously configured to reside in the storage medium with addresses, and be configured to run on one or more processors. Thus, a unit may include, by way of example, components, such as software components, software components object-oriented, class components and task components, processes, functions, attributes, procedures, subroutines, program code segments, firmware, microcodes, circuits, data, databases, data structures, tables, matrices and variables. The functionalities provided in the components and units can be combined into fewer components and modules, or further separated into additional components and units. In addition, the components and units can be applied so that they are executed on one or more CPUs in a communication system. Figure 8 is a schematic illustrating an HT Station transmitting data of inherited format in accordance with an exemplary embodiment of the present invention. The HT Station 100 includes a transmitter unit 110, a receiver unit 120, a coding unit 130, a decoder unit 140, a controller unit 150, a legacy data transmission control unit 160, and two antennas 181 and 182. The antennas 181 and 182 receive and transmit wireless signals. The transmitter unit 110 transmits signals to the antennas 181 and 182, and the coding unit 130 encodes data to generate signals to be transmitted to the antennas 181 and 182 by the transmitter unit 110. To transmit signals through two or more antennas using a technique MIMO, it is necessary to divide the signal data and then code separately. Alternatively, for the purpose of transmitting signals using channel junction, the transmitter unit 110 selects two adjacent channels, including a channel in use and a directly next or directly preceding channel, to be joined to each other, and transmits the signals along the joined channels . The receiving unit 120 receives signals from the antennas 181 and 182, and the decoding unit 140 decodes the signals received by the receiving unit 120 into data. When the data is received using a MIMO technique, it is necessary to integrate the data transmitted by the two channels. The legacy data transmission controlling unit 160 controls data of short duration, for example an Ack frame, a CTS frame or RTS frame, to be transmitted in an inherited format. The control unit 150 manages and controls the exchange of information between the various elements of the HT 100 station. Figure 9 is a flowchart illustrating a method in which an HT station receives an HT frame and transmits an inherited data frame as a response frame, in accordance with an exemplary embodiment of the present invention. The HT station accesses a wireless network in operation S301. In this case, access to the wireless network it involves not only accessing an existing wireless network, but also generating a wireless network again. In an exemplary embodiment, operation S301 may include the generation of a series of basic services (BSS), i.e. an Access Point (AP). Next, a first station in the wireless station receives first data in compliance with a first protocol in step S302. The first protocol includes transmission and reception protocols in an HT format, that is, IEEE 802.11 ?. In addition, the first protocol can include protocols with support for earlier versions of legacy format protocols. The term "backward compatibility", as used herein, means that an updated protocol or software is compatible with previously proposed protocols or software. For example, the IEEE 802.11 protocols? they can interpret data that is transmitted and received in the IEEE 802.11a, 802.11b or 802.11g protocols, and can transmit or receive HT data in the IEEE 802.11a, 802.11b or 802. llg protocols. The same happens when an updated software is available to allow the interpretation or administration of data generated by software of existing versions. After receiving the first data, it is determined if the first data are transmitted using a union of channels in operation S310. If the first data is transmitted using channel junction (YES in operation S310), second data that complies with a second protocol are transmitted by the respective channels used in the union of channels in operation S320. In accordance with the second protocol, the frames that can be interpreted by the receiver channels of the associated legacy data stations in the channel junction are transmitted. Thus, if the first protocol complies with IEEE 802.11 ?, the second protocol includes protocols from previous versions with which the IEEE 802.11? Protocol is compatible, ie IEEE 802.11a, 802.11b, 802. llg or similar. The transmission procedures have been described above with reference to Figure 5. If the first data is transmitted without using channel joining (NO in operation S310), that is, if the first data is transmitted using, i.e., a technique MIMO, the second data that complies with the second protocol in operation S330 is transmitted. The transmission procedure has been described above with reference to Figure 6. As described above, the second protocol includes previous versions of protocols with which the first protocol is compatible. The wireless network shown in Figure 8 can be a BSS with an AP, or a Basic Service Series Independent (IBSS) without AP. The second data is cut data including control boxes, such as Ack, CTS, RTS, etc. INDUSTRIAL APPLICABILITY The second data can be interpreted by legacy data stations, so that legacy data stations can perform virtual carrier detection. Accordingly, the use of the second data improves the efficiency of the transmission in a wireless network without legacy data stations. As described above, and in accordance with exemplary embodiments of the present invention, when HT stations and legacy data stations coexist with different transmission capabilities in a wireless network, the legacy data stations can perform virtual carrier detection. In addition, in accordance with exemplary embodiments of the present invention, short data is transmitted in an inherited format, thus improving transmission efficiency. Those skilled in the art will understand that various changes can be made in the form and details of the present invention, without departing from the spirit and scope of the present invention, as defined in the following claims. Therefore, it can be seen that the Exemplary embodiments described above are for illustrative purposes only, and should not be construed as limiting the present invention. The scope of the present invention is described in the appended claims, rather than in the foregoing description, and it is intended that all variations and equivalents that fall within the range of the claims be encompassed. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (16)

1. CLAIMS Having described the foregoing invention, the content of the following claims is claimed as property: 1. A method for transmitting data to a station in a wireless network, characterized in that it comprises: receiving first data through a linked channel formed by the joining first and second adjacent channels; and transmitting second data by each of the first and second adjacent channels, where the second data is a free frame to send CTS) or request box to send (RTS).
2. 2. The method of compliance with the claim 1, characterized in that the wireless network complies with the IEEE 802.11 ?.
3. 3. The method of compliance with the claim 2, characterized in that the first data comply with the IEEE 802.11 ?.
4. 4. The method according to claim 3, characterized in that the second data are data based on the IEEE 802.11a standard, the IEEE 802.11b standard or the IEEE 802. llg standard.
5. 5. The method according to claim 1, characterized in that the transmission of the second data comprises separately transmitting the second data and simultaneously by each of the first and second adjacent channels.
6. The method according to claim 5, characterized in that the second data is transmitted through the first adjacent channel by a first antenna, and the second data is transmitted by the second adjacent channel by a second antenna.
7. The method according to claim 1, characterized in that the first data complies with a first protocol, and the second data complies with a second protocol, and the first protocol is compatible with the second protocol.
8. The method according to claim 1, characterized in that the second data is transmitted in a Physical Layer Convergence Procedure Protocol (PLCP) Data Unit.
9. 9. A wireless network device characterized in that it comprises: a receiving unit receiving first data transmitted through a linked channel that is formed by a junction of first and second adjacent channels; and a transmitting unit that transmits second data through each of the first and second adjacent channels, where the second data is a free send box (CTS) or a send request box (RTS).
10. 10. The wireless network device of according to claim 9, characterized in that the wireless network complies with the IEEE 802.11 ?.
11. 11. The wireless network device according to claim 10, characterized in that the first data comply with the IEEE 802.11 ?.
12. The wireless network device according to claim 11, characterized in that the second data complies with the IEEE 802.11a standard, the IEEE 802.11b standard or the IEEE 802. llg standard.
13. The wireless network device according to claim 9, characterized in that the transmitting unit transmits the second data separately and (simultaneously) through each of the first and second adjacent channels
14. 14. The wireless network device according to the claim 13, further comprising first and second antennas, characterized in that the transmitting unit transmits the second data through the first adjacent channel using the first antenna, and transmits the second data through the second adjacent channel using the second antenna. of wireless network according to claim 9, characterized in that the first data comply with a first protocol and the second data comply with a second protocol, and the first protocol It is compatible with the second protocol. The wireless network device according to claim 9, characterized in that the second data is transmitted in a Physical Layer Convergence Procedure Protocol (PLCP) Data Unit.