HK1073944B - Method for processing shared sub-packets in a communication system - Google Patents

Description

Method of processing shared sub-packets in a communication system

Background

FIELD

The present invention relates generally to communication systems, and more particularly to a method and apparatus for processing shared sub-packets within a communication system.

Background

Communication systems have been developed to enable the transmission of information signals from an originating station to a physically different destination station. In transmitting an information signal from an origination station over a communication channel, the information signal is first converted into a form suitable for efficient transmission over the communication channel. The transformation or modulation of the information signal involves changing a parameter of the carrier wave in accordance with the information signal such that the resulting modulated carrier wave is spectrally confined within the communication channel band. At the destination station, the original information signal is replicated by the modulated carrier wave received over the communication channel. This replication is typically achieved by using the inverse of the modulation process performed by the origination station.

Modulation also facilitates multiple access, i.e., the simultaneous transmission and/or reception of several signals over a common communication channel. Multiple-access communication systems typically include a plurality of remote subscriber units that require intermittent, relatively short duration service rather than continuous access to a common communication channel. Several multiple access techniques are known in the art, such as Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA) and amplitude modulation multiple Access (AM). Another type of multiple access technique IS the Code Division Multiple Access (CDMA) Spread spectrum System, which conforms to the "TIA/EIA-95-B Mobile Station-base Compatibility Standard for Dual-Mode Wideband Spread Spectrum cellular System", hereinafter referred to as the TIA/EIA-IS-95 Standard. The use of CDMA technology IN MULTIPLE ACCESS COMMUNICATION SYSTEMs is disclosed IN U.S. patent No. 4901307 entitled "forward speech MULTIPLE-ACCESS COMMUNICATION SYSTEM using satellite COMMUNICATION OR TERRESTRIAL REPEATERS" and U.S. patent No. 5103459 entitled "SYSTEM AND METHOD for detecting interference IN a CDMA cellular TELEPHONE SYSTEM", both of which are assigned to the assignee of the present invention.

Multiple-access communication systems may be wireless or wired and may carry voice and/or data. An example of a communication system that carries voice and data IS a system that conforms to the TIA/EIA-IS-95 standard and provides for the transmission of voice and data over a communication channel. A METHOD FOR transmitting DATA in code channel frames OF fixed size is described in detail in U.S. patent No. 5504773, entitled "METHOD AND APPARATUS FOR the TRANSMISSION OF DATA FOR TRANSMISSION", assigned to the assignee OF the present invention. According to the TIA/EIA-IS-95 standard, data or speech IS divided into encoded channel frames that are 20 milliseconds wide with a data rate of 14.4 Kbps. Additional examples of communication systems carrying voice and data include those conforming to "3^rdThe Generation Partnership Project "(3 GPP) communication System IS embodied in a set of documents including Nos.3G TS 25.211, 3G TS 25.212, 3G TS 25.213, and 3G TS25.214(W-CDMA Standard), or" TR-45.5 Physical Layer Standard for CDMA2000Spread Spectrum Systems "(IS-2000 Standard).

An example of a data-only communication system IS a High Data Rate (HDR) communication system that conforms to the TIA/EIA/IS-895 industry standard, hereinafter referred to as the TIA/EIA/IS-895 standard. The HDR is based on a communication system disclosed in appended application Ser. No. 08/963386 entitled "METHOD AND APPARATUS FOR HIGH RATE PACKET DATA TRANSMISSION", filed 3/11/1997 and assigned to the assignee of the present invention. The HDR communication system defines a set of data rates, from 38.4kbps to 2.4Mbps, which is the rate AT which an Access Point (AP) sends data to a subscriber station (access terminal AT). Since an AP is similar to a base station, the terminology with respect to cells and sectors is consistent with that of a voice system.

Existing voice/data communication systems typically use voice traffic channels for voice telephony or data communications including small file transfers, e-mail and facsimile. And thus the data transmission rate is limited. For example, in the TIA/EIA/IS-95 compliant communication system described above, the establishment of multiple traffic channels IS provided, each data rate being up to 14.4 kilobits per second. While 14.4 kilobits per second is sufficient for low data rate applications of the type described above, the increased data intensity of more data intensive applications such as the world wide web and video conferencing create demands for higher data transmission rates. A communication system conforming to the TIA/EIA/IS-895 standard meets the data rate requirements but only allows data transmission. In order to meet the needs of data transmission while maintaining voice service capabilities, several communication systems have been proposed.

One such communication system is the communication system described above that conforms to the W-CDMA standard. Another communication system is described in the proposals handed over by LG electronics, LSI logic, lucent technologies, Nortel networks, QUALCOMM corporation and Samsung to 3rd Generation Partnership Project2(3GPP 2). This Proposal is presented under the title "Updated Joint Physical Layer protocol for 1 xEV-DV" (document number C50-20010611-009, 11.6.2001) and "Updated Joint Physical Layer protocol for 1 xEV-DV", file L3NQS _ Physical _ Layer _ v09.doc, 20.8.2001, hereafter referred to as the 1xEV-DV Proposal. Another communication system is described in the proposal by motorola, nokia, texas instruments and LSI logic to 3GPP 2. This proposal is described in the title "1 XTREMEPE physical Layer specificity for Integrated Data and Voice Services in cdma2000Spread Spectrum Systems", filed under the reference number C50-2001204021 for 3GPP2, 12/8/2000.

The 1xEV-DV proposal provides an air interface between multiple subscriber stations and multiple subscriber stations initiating simultaneous voice and data services. For this purpose, the 1xEV-DV proposal defines a set of forward and reverse channels.

The structure of the reverse channel transmitted by the base station is illustrated in fig. 1. The reverse pilot channel, dedicated control channel and fundamental channel remain unchanged. The supplemental channel structure remains unchanged for radio configurations 1 to 6. The new reverse control channels are a reverse rate indicator channel (R-RICH), a reverse channel quality indicator channel (R-CQICH), and a reverse acknowledgement channel (R-ACKCH).

The forward channel structure transmitted by base station 104(i) is illustrated in fig. 2. The forward pilot channel, transmit diversity pilot channel, secondary transmit diversity pilot channel, synchronization channel, paging channel, broadcast control channel, quick paging channel, common power control channel, common assignment channel, dedicated control channel, forward fundamental channel, forward secondary channel, and forward secondary code channel are the same as the peers in the IS-2000 standard described above. The forward packet data channel, the optimal forward first packet data control channel, and the forward second packet data control channel are channels defined for 1xEV-DV packet data operations.

Data services are provided to subscriber stations on a forward packet data channel (F-PDCH) that is shared for packet data users on a time division multiplex basis. The F-PDCH consists of a plurality of code division multiplexed Walsh subchannels. The number of sub-channels varies in time with the requirements of the circuit-switched voice and data users. The F-PDCH structure is illustrated in FIG. 3. The information bit stream 302 to be transmitted is divided into packets of several sizes. A 16-bit Cyclic Redundancy Check (CRC) is added to each packet in block 302 and a 6-bit turbo encoder tail redundancy generating encoder packet is added in block 306. In an embodiment, the encoder packet size is 384 bits, 768 bits, 1536 bits, 2304 bits, 3072 bits, and 3840 bits. The encoder packet is encoded by module 308. Each encoded packet is then scrambled within module 310 by the scrambling pattern generated by module 312 and interleaved via module 314. Some or all of the interleaved symbols are then selected to form subpackets in block 316. Depending on the length of the sub-packet, the sub-packet comprises 1, 2, 4 or 8 slots. In one embodiment, the time slot is 1.25 milliseconds long. The sub-packets are QPSK, 8-PSK, or 16-QAM modulated by block 318 and demultiplexed into a variable number of parallel stream pairs (in-phase and quadrature) by block 320. Each parallel stream is covered with a different 32-ary Walsh function by module 322 (i). The Walsh encoded symbols for all streams are summed by module 324 to form a single in-phase stream and a single ac stream. The in-phase and quadrature streams are provided to a module 326 which adjusts the channel gain. Several forward link channels, data and voice, are then summed in block 328, quadrature spread in block 330, the in-phase and quadrature streams generated in block 332(i) are baseband filtered, upconverted in block 334(i), and summed in block 336.

The F-PDCH is controlled by a forward first packet data control channel (F-PPDCCH), if used, and a forward second packet data control channel (F-SPDCCH).

The F-PPDCH is transmitted in the first time slot of the F-PDCH transmission and carries a 2-bit field indicating the length of the F-PDCH subpacket. Those of ordinary skill in the art realize that the use of F-PPDCCH is optional since F-PPDCCH carries only information on the length of the F-DPCH sub-packet. The subscriber station may use other methods to determine the F-PDCH subpacket length. Thus, for example, the subscriber station may decode the subpackets for all subpacket length hypotheses and select the most likely one.

The F-SPDCCH is sent on 1, 2, or 4 time slots and the start of the F-SPDCCH transmission is aligned with the start of the corresponding F-PDCH transmission. The F-SPDCCH carries bits specifying a Medium Access Control (MAC) Identifier (ID), an automatic repeat request (ARQ) channel ID, an encoder packet size, and an F-PDCH subpacket ID.

The 1xEV-DV proposal thus enables a base station to transmit data to multiple mobile units over a single time slot. In addition, the highest subpacket data rate allowed for a 384-bit packet is 307.2kbps, one slot per subpacket. So even when mobile units are able to receive higher data rates, they are limited to a maximum of 307.2kbps and use at least one slot.

Similarly, the 1xTREME proposal provides an air interface between multiple subscriber stations and multiple subscriber stations that enables simultaneous voice and data services. The 1xTREME proposal uses a fixed sub-packet size of 5 milliseconds for both the packet data channel and the control channel associated with the packet data channel. The packet data subpackets may be CDM shared, but there is no flexibility in the duration of the data or control subpackets. The packet data channel is controlled by a dedicated CDM channel (referred to as a forward dedicated pointer channel) and a shared control channel (referred to as a forward shared control channel) for each user.

The fixed duration shared packet data sub-packets and limited control proposed by 1xTREME or 1xEV-DV wastes resources and limits system throughput performance. As a result, there is a need in the art for a method and apparatus for enabling multiple forward link transmissions per time slot to improve system throughput.

SUMMARY

In one aspect of the present invention, the above-mentioned requirements are achieved by: generating a first control channel comprising an indicator indicating a traffic channel to share and a parameter of the traffic channel; and generating at least one second control channel, each of said at least one second control channel comprising an identification of at least one subscriber station and information enabling the subscriber station to demodulate the traffic channel.

In another aspect of the present invention, the above need is achieved by: demodulating the first control channel to determine whether a shared traffic channel; if the traffic channel is shared, determining the number of subscriber stations sharing the traffic channel and multiplexing the traffic channel according to said demodulated first control channel; demodulating a second control channel, the channel comprising an identity of the subscriber station and information enabling the subscriber station to demodulate the traffic channel; and demodulating the traffic channel in accordance with said multiplexing and enabling information if the obtained identity is consistent with the identity of the subscriber station.

Brief description of the drawings

Fig. 1 illustrates a structure of a reverse channel transmitted by a base station;

fig. 2 illustrates a structure of a reverse channel transmitted by a base station;

fig. 3 is an exemplary forward packet data channel;

FIG. 4 illustrates a sub-packet structure according to one embodiment;

FIG. 5 illustrates a sub-packet structure according to one embodiment;

FIG. 6 illustrates a control channel structure in accordance with an embodiment;

FIG. 7 illustrates a control channel structure in accordance with another embodiment;

FIG. 8 illustrates a control channel structure in accordance with another embodiment;

fig. 9 illustrates a CDM channel structure in accordance with an embodiment;

FIG. 10 illustrates a control channel structure in accordance with another embodiment;

FIG. 11 illustrates a control channel structure in accordance with another embodiment;

FIG. 12 illustrates a control channel structure in accordance with another embodiment;

FIG. 13 illustrates a control channel structure in accordance with another embodiment;

Detailed Description

Definition of

The term "exemplary" is used herein to mean "serving as an example, instance, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

The term packet herein refers only to a group of bits, including data (payload) and control elements arranged into a particular format. Control elements include, for example, preamble sequences, quality metrics, and others known to those skilled in the art. Quality metrics include, for example, Cyclic Redundancy Check (CRC), parity bits, and others known to those skilled in the art.

The term access network herein refers only to a collection of Access Points (APs) and one or more access point controllers. An access network transmits data packets between a plurality of Access Terminals (ATs). The access network may be further connected to additional networks outside the access network, such as a corporate intranet or the internet, and may transport data packets between each access terminal and such outside networks.

The term base station is used herein to refer to an AP in an HDR communication system and is used herein to refer only to the hardware that communicates with subscriber stations. A cell refers to either hardware or a geographic coverage area, depending on the environment in which the term is used. A sector is a partition of a cell. All the principles herein relating to cells can be extended to sectors, since sectors have the properties of cells.

The term subscriber station is used herein to refer to an AT in an HDR communication system, and is used herein to refer only to hardware that communicates with an access network. The AT may be mobile or stationary. An AT may be any data device that communicates through a wireless channel or through a wired channel, such as fiber optic or coaxial cables. The AT may also be one of any type of device, including but not limited to: PC card, compact flash, external or internal modem, or wireless or wireline phone. An AT that is establishing an active traffic channel connection with an AP is said to be in a connection setup state. An AT that has established an active traffic channel connection with an AP is referred to as an active AT and is also referred to as being in a traffic state.

The term communication channel/link is used herein to refer to only a single route over which a signal is transmitted or a single route within the protocol layer of an AP or AT described using modulation methods and coding.

The term reverse channel/link is used herein to refer only to the communication channel/link through which the AT sends signals to the AP.

The forward channel/link herein refers only to the communication channel/link through which the AP sends signals to the AT.

The term soft handoff is used herein to refer to communication between a subscriber station and two or more sectors, where each sector belongs to a different cell. In the context of the TIA/EIA/IS-95 standard, reverse link communications are received by two sectors and forward link communications are carried on the forward links of two or more sectors simultaneously. In the context of the TIA/EIA/IS-895 standard, data transmission on the forward link does not occur simultaneously between one of the two or more sectors and the AT.

The term softer handoff is used herein to refer to communication between a subscriber station and two or more sectors, where each sector belongs to the same cell. In the context of the TIA/EIA/IS-95 standard, reverse link communications are received by a sector and forward link communications are simultaneously conducted on two or more sector forward links. In the context of the TIA/EIA/IS-895 standard, data transmission on the forward link does not occur simultaneously between one of two or more sectors and the AT.

The term re-pointing herein refers to selecting only one sector in the AT active list, where the sector is different from the currently selected sector.

Soft/softer handoff delay refers herein to only the minimum interruption of service that a subscriber station would experience in soft handoff to another sector. Soft/softer handoff is based on whether the sector (currently non-serving subscriber station) to which the subscriber station is being redirected is part of the same cell as the currently serving sector. A softer handoff delay is used if the non-serving sector is in the same cell as the serving sector, and a partial soft handoff delay is used if the non-serving sector is in a different cell than the serving sector.

Non-uniform soft/softer handoff delays here simply mean that the soft/softer handoff delays are sector specific and therefore not uniform across the sectors of the access network.

The term scoring is used herein to refer only to dimensionless attributes that specify a quality metric for the reverse link, a quality metric for the forward link, or a composite quality metric for the forward and reverse links.

Erasing a word merely means that a message cannot be identified.

The term quiesce herein refers only to a time interval in which the subscriber station has a reduced likelihood of receiving service.

The term fixed rate mode is used herein to refer only to the particular sector transmitting the forward traffic channel to the AT a particular rate.

Description of the invention

The present invention uses the sub-packet structure as defined in the 1xEV-DV proposal, but further partitions the sub-packet granularity. In the following description, channels are discussed in a structural form to understand the principles of the present invention. Those skilled in the art will appreciate that the channel structure may contain additional elements required for transmission, such as CRC, encoder tail bits, and other modules known to those of ordinary skill in the art.

Fig. 4 illustrates a sub-packet structure according to an embodiment. Subpacket 400 includes one or more slots 402 (i). Each time slot 402(i) is further time divided into sub-time slots 404 (i). (only one slot sub-partition is shown). In one embodiment, there are 2, 4, or 8 equal sub-slots 404 (i). However, one skilled in the art will appreciate that sub-segmentation is an implementation choice and that other sub-segmentations are within the scope of the invention. Data to the subscriber station is provided in one or more sub-slots 404 (i). Multiple sub-slots 404(i) may be used by each subscriber station, and the number of sub-slots for each subscriber station using each sub-packet may be different.

According to another embodiment illustrated in fig. 5, time slot 502(i) of sub-packet 500 contains data for several subscriber stations. All of the time slots 502(i) from the subpacket 500 for a particular mobile unit are transmitted using one or more available Walsh channels. As illustrated in fig. 5, time slots 402(1) - (n) contain data encoded by Walsh codes 504(1) - (504 (m), and thus carry data for m subscriber stations. Thus, the number of subscriber stations receiving information concurrently may vary on a sub-packet to sub-packet basis.

Control structure

Due to the variability of the F-PDCH described above, the subscriber station must be provided with information to enable the subscriber station to demodulate the F-PDCH. In embodiments using code division of sub-packets, existing F-PPDCCH and F-SPDCCH may be used. Those skilled in the art will appreciate that while the following description describes modifications of the F-PPDCCH and F-SPDCCH, this is for illustration purposes only and new channels may be defined in accordance with the described embodiments. Additional information is carried on one or more new channels.

Fig. 6 illustrates a control channel structure including a F-PPDCCH 600, a F-SPDCCH602, and one CDM control channel 608(i) for each subscriber station sharing a subpacket, according to one embodiment. The F-PPDCCH 600 is used as defined in the 1xEV-DV proposal. Those skilled in the art will appreciate that the use of F-PPDCCH is optional since it only carries information about the length of the F-PDCH subpacket. The subscriber station may use other methods to determine the F-PDCH subpacket length. Thus, for example, the subscriber station may decode subpackets for all subpacket length hypotheses and select the most likely one.

Similarly, F-SPDCCH602 is used as defined in the 1xEV-DV proposal with the following modifications. One MAC ID value of module 604 is reserved to identify that sub-packets of the F-PDCH are to be shared. According to an embodiment, the MAC ID value identifies that the sub-packet to be shared is all sub-packets. Since all subscriber stations to which the shared subpacket is directed must reliably receive the information content of channel 602, channel 602 is transmitted at a power determined by the power requirement of the subscriber station with the worst forward link quality metric to which the control channel 602 is directed. Upon receiving the channel 602, each subscriber station demodulates and decodes the MAC ID of the module 604. If the MAC ID indicates that the sub-packet is for one subscriber station, the identified subscriber station processes the sub-packet according to the procedures set forth in the 1xEV-DV proposal.

If the MAC ID indicates that the sub-packet is to be shared, the remaining bits of the module 606 are interpreted as parameters indicating the shared sub-packet. The parameter includes a number of subscriber stations sharing the sub-packet. Thus, each subscriber station acquires this information and then begins receiving CDM channel 608 (i). Since each CDM channel 608(i) is modulated by a Walsh code, the subscriber station needs to know these Walsh codes. In one embodiment, a predetermined Walsh code is reserved for CDM channel 608 (i). In another embodiment, the subscriber station is informed of the Walsh code through a signaling message. Only CDM channels 608(i) equal to the number of subscriber stations sharing the sub-packet are sent and transmission occurs only when the sub-packet is shared. In one embodiment, CDM channels 608(i) are sent concurrently, so each subscriber station accumulates data from all CDM channels 608(i), and then post-processes the accumulated data. Since each CDM channel 608(i) is directed to one subscriber station and the base station has information on the subscriber station's forward link quality metric, the base station transmits each CDM channel 608(i) at the minimum power determined by the power requirements of the subscriber station.

Each CDM channel 608(i) includes information that enables a subscriber station to determine which CDM channel 608 is directed to the subscriber station, and information that enables the subscriber station to demodulate the F-PDCH. The information that enables the subscriber station to determine which CDM channel 608 is directed to the subscriber station includes MAC ID 610 (i). The information that enables the subscriber station to demodulate the F-PDCH includes the ARQ ID 612(i), the sub-packet ID 616(i), the packet size 618(i), and the number of Walsh channels 620(i) used. In an embodiment, current F-PDCCH coding and modulation is used for each CDM channel 608 (i). In post-processing, each subscriber station demodulates the MAC ID 610(i) of CDM channel 608 (i). If the mac id 610(i) indicates that the CDM channel 608(i) does not contain information to the subscriber station, the subscriber station stops further processing of the channel and repeats the processing for the next CDM channel 608(i + 1). If the subscriber station demodulates the mac id 610(i) indicating that the CDM channel 608(i) contains information to the subscriber station, the subscriber station demodulates the remaining information and processes the subpackets on the F-PDCH according to the collected information.

In another embodiment using subpacket code division, information is provided on the F-PPDCCH, F-SPDCCH, and one CDM channel for all subscriber stations sharing a subpacket. Thus, the F-PPDCCH and F-SPDCCH have the structure depicted in FIG. 6. The structure of the CDM channel carries information that enables each subscriber station to demodulate the F-PDCH. The information for all subscriber stations is time multiplexed, then coded and modulated. Thus, the CDM channels include a concatenation of CDM channels 608(i) as described in FIG. 6. In an embodiment, the current F-SPDCCH coding and modulation is used for CDM channels. Thus, the method of acquiring information is the same as described above, except that one point, all subscriber stations, demodulates and decodes the entire information carried on the CDM channel. The subscriber station then checks the MAC ID. If the subscriber station cannot find a MAC ID indicating that the subscriber station is to share the subpacket, the subscriber station stops further processing. If the subscriber station finds a MAC ID indicating that the subsequent portion of the CDM channel contains information for the subscriber station, the subscriber station demodulates the information and processes the subpackets on the F-PDCH according to the collected information.

Those skilled in the art will appreciate that sharing a limited number of subscriber stations in a sub-group will simplify the above embodiment. Thus, in embodiments where only two subscriber stations are allowed to share a subpacket, the existing F-PPDCCH and F-SPDCCH modified structure may be used. Therefore, no additional control channel is required.

The F-PPDCCH is used as defined in the 1xEV-DV proposal. Those skilled in the art will appreciate that the use of F-PPDCCH is optional since it only carries information about the length of the F-PDCH subpacket. The subscriber station may use other methods to determine the F-PDCH subpacket length. Thus, for example, the subscriber station may decode subpackets for all subpacket length hypotheses and select the most likely one.

Fig. 7 illustrates the structure of modified F-SPDCCH 700. Modified F-SPDCCH 700 includes information that enables both subscriber stations to demodulate the F-PDCH. Thus, F-SPDCCH 700 includes the MAC ID of each subscriber station 701(1), 701(2), ARQID 702(1), 704(2), subpacket ID 706(1), 706(2), encoder packet size 708(1), 708(2), and the number of Walsh channels 710(1), 710(2) used. The structure can be further simplified if the second subscriber station is assumed to use a number of Walsh channels less than or equal to the number of Walsh channels of the second subscriber station. Modified F-SPDCCH 700 includes only modules 710(1), 710 (2).

Since all subscriber stations that are designated to share subpackets must reliably receive modified F-SPDCCH 700, modified F-SPDCCH 700 is transmitted at a power determined by the power requirements of the subscriber station with the worst forward link metric to which modified F-SPDCCH 700 is directed. Upon receiving the modified F-SPDCCH 700, each subscriber station demodulates the modified F-SPDCCH 700 and demodulates the MAC ID within modules 702(1), 702 (1). If the subscriber station's MAC ID is the same as any of the decoded MAC IDs, the subscriber station obtains the remaining information from the modified F-SPDCCH 700 and processes the sub-packets of the F-PDCH according to the information.

The modified F-SPDCCH 700 is transmitted even if the F-PDCH is directed to only one subscriber station. In this case, MAC ID 702(2) is the same as MAC ID 702 (1). Therefore, the subscriber station ignores module 704(2) as the ARQ ID, 706(2) as the subpacket ID, 708(2) as the encoder packet size, and 710(2) as the number of Walsh channels 710(1) used. Thus, these modules may be used for any additional information. The subscriber whose MAC ID is the same as the decoded MAC ID obtains the remaining information from the modified F-SPDCCH 700 and processes the subpackets of the F-PDCH according to the procedure defined within 1 xEV-DV.

According to another embodiment, existing F-PPDCCH and F-SPDCCH may be used. The F-PPDCCH is used as in the 1xEV-DV proposal. Those skilled in the art will appreciate that the use of F-PPDCCH is optional since it only carries information about the length of the F-PDCH subpacket. The subscriber station may use other methods to determine the F-PDCH subpacket length. Thus, for example, the subscriber station may decode subpackets for all subpacket length hypotheses and select the most likely one. The F-SPDCCH includes information to enable one of the two subscriber stations to demodulate the F-PDCH and an indicator to indicate whether another CDM control channel is transmitted. The CDM control channel includes information that enables one subscriber station to demodulate the F-PDCH.

Fig. 8 illustrates a control channel structure F-SPDCCH 800 and CDM control channel 802. F-SPDCCH 800 includes MAC ID 804, ARQ ID 806, subpacket ID 808, encoder packet size 810, and the number of Walsh channels 812 used for one of the two possible shared channels, and CDM indicator 814.

CDM channel 802 comprises MAC ID 816, ARQ ID 818, subpacket ID 820, encoder packet size 822, and the number of Walsh channels 824, if used, for the second shared channel. If the F-PDCH subpacket is not shared, CDM channel 802 is not transmitted for the subpacket.

In an embodiment, F-SPDCCH 800 and CDM control channel 802, if used, are sent concurrently. Since subscriber stations do not know whether to transmit CDM control channels 802, each subscriber station accumulates data from F-SPDCCH 800 and all CDM channels 802 and then post-processes the accumulated data. Since the subscriber station to share the subpackets must reliably receive F-SPDCCH 800, F-SPDCCH 800 is transmitted at a power determined by the subscriber station's power requirement with the worst forward link quality metric to which F-SPDCCH 800 is directed. Since CDM control channel 802 is directed to one subscriber station and the base station has information about the forward link quality metric of the subscriber station, the base station transmits CDM control channel 802 at the minimum power determined by the power requirements of the subscriber station.

Upon receiving the modified F-SPDCCH 800, each subscriber station decodes the MAC ID 802. If the decoded MAC ID is the same as the subscriber station MAC ID, the subscriber station decodes the remaining information from the F-SPDCCH 800 and processes the sub-packets of the F-PDCH according to the information.

The subscriber station whose MAC ID is different from the decoded MAC ID decodes CDM indicator 814. If CDM indicator X214 indicates that CDM control channel 802 is not being sent, the subscriber station stops further processing; otherwise the subscriber station decodes the MAC ID 816. The subscriber station whose MAC ID is the same as the decoded MAC ID acquires the remaining information from the CDM control channel 802 and processes the subpackets of the F-DPCH according to the information. Subscriber stations whose MAC ID is not the same as the decoded MAC ID cease further processing.

In another embodiment using time division of the F-PDCH subpacket, control information is provided on one CDM channel for each of the F-PPDCCH, F-SPDCCH, and subscriber stations sharing the subpacket.

The function and structure of the F-PPDCCH is the same as that of the F-PPDCCH, as described with respect to CDM based on F-PDCH subpacket sharing.

Similarly, the function and structure of the F-PSDCCH are the same as those of the F-PSDCCH described above with respect to CDM based on sub-packet sharing with the following modifications. If the MAC ID indicates that a sub-packet of the F-PDCH is to be shared, the remaining bits of the F-SPDCCH are interpreted to indicate the shared sub-packet parameters, which include the number of sub-packets divided into sub-slots and the number of subscriber stations sharing the sub-packet. Thus, each subscriber station demodulates the modified F-SPDCCH and decodes the MAC ID. If the MAC ID indicates that the sub-packet is for a subscriber station, the identified subscriber station processes the sub-packet according to the procedures set forth in the 1xEV-DV proposal.

If the MAC ID indicates that the subpacket is to be shared, the subscriber stations may use the remaining bits of the F-SPDCCH to determine the number of subslots into which the subpacket is divided and the number of subscriber stations sharing the subpacket. Thus, each subscriber station obtains this information and then begins receiving TDM channels 900(i), as illustrated in fig. 9. Since each CDM channel 900(i) is modulated by Walsh codes, the subscriber station needs to know these Walsh codes. In an embodiment, a predetermined Walsh code is reserved for CDM channel 900 (i). In another embodiment, the subscriber station is informed of the Walsh code through a signaling message. Only CDM channels 900(i) equal to the number of subscriber stations sharing a sub-packet are sent and transmission occurs only when the sub-packet is shared. In one embodiment, CDM channels 900(i) are sent in parallel, so each subscriber station accumulates data from all TDM channels 900(i) and then processes the accumulated data. Since each CDM control channel 900(i) of a TDM shared F-PDCH is directed to one subscriber station and the base station is informed of the subscriber station's forward link quality metric, the base station transmits each CDM control channel 900(i) with just enough power to reliably reach the designated subscriber station.

Each CDM control channel 900(i) includes information that enables a subscriber station to determine which CDM channel 900(i) is intended for the subscriber station, and information that enables the subscriber station to demodulate the F-PDCH. The information that enables a subscriber station to determine which CDM channel 900(i) is to the subscriber station includes the MAC ID 902 (i). The information that enables the subscriber station to demodulate the F-PDCH includes the ARQ ID 904(i), the subpacket ID 906(i), the shared subpacket format 908(i), and the starting sub-slot 910(i) for each mobile. In an embodiment, current F-PDCCH coding and modulation is used for each CDM channel 900 a. During post-processing, each subscriber station demodulates the MACID 902(i) of the control channel 900 (i). If the MAC ID 902(i) indicates that the control channel 900(i) does not contain information to the subscriber station, the subscriber station stops further post-processing of the channel and repeats the process for the next control channel 900(i + 1). If the subscriber station demodulates the MAC ID 902(i) of the control channel 900(i) and the MAC ID 902(i) indicates that the control channel 900(i) contains information to the subscriber station, the subscriber station reads the remaining information and processes the subpackets on the F-PDCH according to the collected information.

In another embodiment using time division of time slots, the F-PPDCCH, F-SPDCCH, and one TDM channel to all subscriber stations sharing a subpacket provide information. The TDM channel is modulated by information that enables each subscriber station to demodulate the F-PDCH. The information for all subscriber stations is time multiplexed, encoded, and modulated. Thus, a CDM channel includes a concatenation of CDM channels 900(i) as described in fig. 9. In an embodiment, the current F-SPDCCH coding and modulation is used for CDM channels. Thus, the method of acquiring the information is the same as described above, except that one point, all subscriber stations, tune to the CDM channel, demodulate and decode the entire information. The subscriber station then checks the MAC ID. If the subscriber station cannot find the MAC ID indicating that the subscriber station shares the subpacket, the subscriber station stops further processing. If the subscriber station fails to indicate that the subscriber station shares the MAC ID of the sub-packet, the subscriber station reads the remaining information and processes the sub-packet on the F-PDCH according to the collected information. In addition, each subscriber station checks each part of the F-SPDCCH containing information about the sub-slot position. Thus, the CDM channel need not contain the starting sub-slot for each subscriber station, as subscriber stations have acquired information during the sub-slots directed to other subscriber stations.

A control channel structure according to another embodiment is illustrated in fig. 10. The control channel 1002 includes an indication of a plurality of control channels 1008(i) within the module 1004. In addition, each module 1006(i) identifies the MAC ID of a subscriber station to which information is sent on the F-PDCH. In order to receive the control channel 1002, the subscriber station must know the modulation scheme of the control channel 1002. In one embodiment, the modulation parameters are predetermined. In another embodiment, the modulation parameters are provided to the subscriber station via signaling messages. Since all subscriber stations must reliably receive the control channel 1002, the transmit power of the control channel 1002 is determined by the power requirement of the subscriber station with the worst forward link quality metric. Upon receipt of control channel 1002, each subscriber station having the same MAC ID as the MAC ID obtained from module 1006(i) then obtains a control channel 1008 (i). Thus, the number of control channels 1008(i) transmitted is equal to the number of MAC IDs in channel 1002. Subscriber stations with MAC IDs different from the MAC ID obtained from module 1006(i) cease further control channel processing.

Each additional control channel 1008(i) includes information that enables subscriber stations identified by one MAC ID to demodulate the F-PDCH. Thus, in one embodiment, each control channel includes information of the ARQ channel ID, encoder packet size, and F-PDCH subpacket ID, as well as subpacket TDM/CDM shared as above.

To obtain that the subscriber station identified by a MAC ID within control channel 1002 demodulates the F-PDCH, there must be a relationship between the subscriber station MAC ID and the control channel 1008(i) containing information to that subscriber station. In one embodiment, the relationship is determined by the location of module 1006(i) within channel 1002 and the index to the Walsh code encoded for control channel 1008 (i). Thus, for example, increasing the order of MAC ID positions within the control channel 1002 means increasing the index of the Walsh code encoding the control channel 1008 (i). The relationship between the Walsh code and the MAC ID of the control channel may be predetermined or may be changed by a signaling message. However, one skilled in the art will appreciate that other relationships are within the scope of the invention. Since each additional control channel 1008(i) is directed to one subscriber station and the base station has information about the subscriber station's forward link quality metric, the base station transmits each channel 1008(i) at a minimum power determined by the power requirements of the subscriber station.

Once the subscriber station demodulates the appropriate control channel 1008(i), the subscriber station decodes the information that enables F-PDCH demodulation and processes the subpackets on the F-PDCH based on the collected information.

A control channel structure according to another embodiment is illustrated in fig. 11. Each control channel 1102(i) contains information needed for all subscriber stations to decode the F-PDCH. Thus, in one embodiment, each channel 1102(i) includes a MAC ID module 1104, an ARQ channel ID module 1106, an encoder packet size module 1108, and a F-PDCH subpacket ID module 1110, along with information for subpacket TDM/CDM sharing as described above, collectively identified as module 1112. Since each control channel 1102(i) is directed to one subscriber station and the base station is informed of the subscriber station's forward link quality metric, the base station transmits each channel 1108(i) at the minimum power determined by the power requirements of the subscriber station.

In order to receive the control channel 1102(i), the subscriber station must know the modulation parameters of the control channel 1102 (i). In one embodiment, the modulation parameters and the number of possible control channels are predetermined. In one embodiment, the modulation parameters include different Walsh codes. Since there is no relationship between one subscriber station and one control channel 1102(i) according to the embodiment, the subscriber station must demodulate all of the control channels 1102 (i). Although the number of control channels 1102(i) transmitted is equal to the number of subscriber stations whose information is transmitted on the F-PDCH, the number of control channels 1102(i) transmitted is changing, because the number of subscriber stations may change according to the granularity of the F-PDCH described above.

In one embodiment, the control channels 1108(i) are sent concurrently, so each subscriber station accumulates data for all channels 1108(i) and then post-processes the accumulated data. During post-processing, one control channel 1102(i) is demodulated and the MAC ID of block 1104(i) is decoded. If the decoded MAC ID is the same as the subscriber station MAC ID, the remaining information is demodulated and the subpackets on the F-PDCH are processed according to the collected information. If the MAC ID of module 1104(i) indicates that channel 1108(i) does not contain information to the subscriber station, the subscriber station stops further processing and the process repeats for the next channel 1108 (i). Since, as noted, the subscriber station has no information about the number of control channels 1108(i) sent, unless the subscriber station finds a MAC ID that indicates that the channel 1108(i) contains information to the subscriber station, the subscriber station must attempt to demodulate all possible control channels 1108 (i).

A control channel structure according to another embodiment is illustrated in fig. 12. Each control channel 1202(i) contains information needed for all subscriber stations to decode the F-PDCH. Thus, in one embodiment, each channel 1202(i) includes a MAC ID module 1204, an ARQ channel ID module 1206, an encoder packet size module 1208, and an F-PDCH subpacket ID module 1210, along with information for subpacket TDM/CDM sharing described above, identified collectively as module 1212. In addition, one control channel 1202(i), e.g., control channel 1202(1), includes a spreading module 1214 that identifies the number of control channels 1202(i) transmitted. Since all subscriber stations are required to reliably receive the contents of the control channel 1202(1), in one embodiment, the control channel 1202(1) is transmitted at a power determined by the power requirement of the subscriber station with the worst forward link quality metric. Since each control channel 1202(2) - (1202 m) is directed to one subscriber station and the base station has information about the subscriber station's forward link quality metric, the base station transmits each channel 1202(2) - (1202 m) at the minimum power determined by the power requirements of the subscriber station.

In order to receive the control channel 1202(i), the subscriber station must know the modulation parameters of the control channel 1202 (i). In an embodiment, the modulation parameters and the number of possible control channels are predetermined. In addition, there is a relationship between the control channel 1202(i) and the modulation parameters. In an embodiment, the modulation parameters include different Walsh codes, and the transmitted control channels 1202(i) are encoded with sequentially indexed Walsh codes. However, one skilled in the art will appreciate that other relationships are within the scope of the invention. Since there is no relationship between one subscriber station and one control channel 1202(i) according to the embodiments, the subscriber station must demodulate all of the transmitted control channels 1202 (i). Although the number of multiple transmitted control channels 1202(i) is equal to the number of subscriber stations whose information is transmitted on the F-PDCH, the number of transmitted control channels 1202(i) is changing, because the number of subscriber stations may vary according to the granularity of the F-PDCH described above.

In one embodiment, the channels 1202(i) are sent concurrently, so each subscriber station accumulates data for all channels 1202(i) and then post-processes the accumulated data. During post-processing, each subscriber station first demodulates control channel 1202(1) and decodes the MAC ID of module 1204. Subscriber stations having a MAC ID that is the same as the MAC ID of module 1204 decode the remaining information and process the subpackets of the F-PDCH according to the collected information. If the MAC ID of the subscriber station is different than the MAC ID of module 1204, then the number of control channels 1202(i) sent by module 1214 is decoded, the control channels 1202(1) are stopped for further post-processing, and the process is repeated for the next channel 1208 (i). Thus, the subscriber station has information about the number of control channels 1208(i) transmitted. Since, as described, there is a relationship between the transmitted control channels 1208(i), the subscriber station only attempts to demodulate the transmitted channels 1208(i) unless the subscriber station finds a MAC ID that indicates that the channel 1208(i) contains information to the subscriber station.

The control channel structure according to another embodiment is the same as the control channel structure illustrated in fig. 12, except for the relationship between the control channel 1202(i) and the modulation parameters. As described above, it is desirable for all subscriber stations to reliably receive the information content of the control channel 1202(1), and in one embodiment, the control channel 1202(1) is transmitted at a power determined by the power requirement of the subscriber station with the worst forward link quality metric. In addition, each control channel 1202(2) - (1202 (m) is directed to one subscriber station, and the base station is informed of the subscriber station's forward link quality metric, so that the base station transmits each channel 1202(2) - (1202 (m) at the minimum power determined by the power requirements of the subscriber station. The transmitted control channels 1202(i) are ordered according to transmit power and modulated by an ordered set of modulation parameters, and the control channels 1202(i) are encoded by ascending Walsh codes associated with increasing transmit power. However, one skilled in the art will appreciate that other relationships are also within the scope of the invention.

In one embodiment, the channels 1202(i) are sent concurrently, so each subscriber station accumulates data from all of the channels 1202(i) and then post-processes the accumulated data. During post-processing, each subscriber station first demodulates the control channel 1202(1) and decodes the MAC ID of the module 1204. Subscriber stations with the same MAC ID as module 1204 decode the remaining information and process the subpackets on the F-PDCH according to the collected information.

Subscriber stations whose MAC IDs are not the same as the MAC ID of module 1204 decode the number of control channels 1202(i) sent by module 1214, cease (1) further post-processing of the control channels 1202, and determine the control channels 1202(2) -1202(m) to be demodulated next. Due to the above-described relationship between the power of the control channel 1202(i) and the Walsh code index encoded by the control channel 1202(i), when the subscriber station attempts to decode one of the control channels 1202(2) -1202(m) and fails to decode, the subscriber station knows that it is also likely that the subscriber station will fail for any of the channels 1202(2) -1202(m) that are transmitted at a lower power. Therefore, the subscriber station next attempts to decode one of the control channels 1202(2) -1202(m) that was transmitted at the higher power. Thus, one skilled in the art will appreciate that any sorted-set-based determination method may be used.

For example, according to one embodiment, the determination method may use a binary search method. If the subscriber station experiences a forward link with a high quality metric, the subscriber station demodulates the control channel with the lowest power 1202(m), and therefore encodes the Walsh code with the highest index m. If the decoding fails, the subscriber station repeats the processing with the control channel at an intermediate power 1202(m/2), and is thus encoded by the Walsh code with index m/2. If the decoding is successful, but the MAC ID indicates that the control channel 1202(m/2) does not contain information for the subscriber station, the subscriber station repeats the process with the control channel between 1202(m/2) and 1202 (m). The method is repeated until the subscriber station processes all control channels between 1202(m/2) and 1202(m) or finds a control channel 1202(i) with a MAC ID indicating that the control channel 1202(i) is directed to the subscriber station.

In another embodiment, subscriber stations whose MAC ID is not equal to that of module 1204 measure power from control channel 1202(i) between ranges 1202(2) - (1202 (m)). If the measured power is higher than the power required by the subscriber station, the control channel 1202(i) containing information to the subscriber station may be within the range 1202(i) -1202 (m). The subscriber station may continue to measure power using a deterministic method, such as the binary search described above or selecting a control channel from a deterministic range and attempting demodulation.

The control channel structure according to another embodiment is the same as that illustrated in fig. 12, except for one point, namely the relationship between the control channel 1202(i) and the modulation parameters. According to an embodiment, the transmitted control channels 1202(i) are reordered according to MAC ID values within module 1204 and modulated by an ordered set of modulation parameters. In one embodiment, the modulation parameters include different Walsh codes, and the control channel 1202(i) is encoded with Walsh codes in ascending order, which is related to the ascending value of the MAC ID in module 1204. However, those skilled in the art will recognize that other relationships are also within the scope of the invention.

Thus, the subscriber station may use any determination method applicable to the ordered set, such as one of the methods described above.

A control channel structure according to another embodiment is illustrated in fig. 13. Each control channel 1302(i) contains information needed for all subscriber stations to decode the F-PDCH. Thus, in one embodiment, each channel 1302(i) includes: a MAC ID module 1306(i) that identifies the subscriber station to which channel 1302(i) is directed; a partial MAC ID module 1308(i) that identifies the subscriber station to which another control channel 1302(i) is directed; and an information module 1310(i) that enables the subscriber station identified by the MAC ID of module 1306(i) to demodulate the F-PDCH. Additionally, one of the control channels 1302(i), e.g., control channel 1302(1), includes a module 1304 that identifies the number of control channels 1302 (i). Identification of partial MAC IDs is an implementation issue. In one embodiment, the MAC ID is represented as an 8-bit number. Thus, the subset of bits identifies the partial MAC ID. In one embodiment, the subset contains the most significant MACID bits.

In order to receive the control channel 1302(i), the subscriber station must know the modulation parameters of the control channel 1302 (i). In an embodiment, the modulation parameters and the number of possible control channels are predetermined. In one embodiment, the modulation parameters include different Walsh codes. However, one skilled in the art will appreciate that other relationships are within the scope of the invention. In addition, there is a relationship between the control channels 1302(2) - (1302 (m) and the partial MAC IDs. This relationship is determined by a method for selecting the next control channel 1302(i) to demodulate for the subscriber station control channel 1302(i) whose MAC ID matches the partial MAC ID. One skilled in the art will recognize that this relationship is an implementation issue. According to one embodiment, the partial MACID from module 1308(i) of channel 1302(i) identifies control channel 1302 (m-i-1).

Since all subscriber stations must reliably receive control channel 1302(1), control channel 1302(1) is transmitted at the power determined by the power requirement of the subscriber station with the worst forward link quality metric. Since each control channel 1302(2) -1302(m) is directed to one subscriber station and the base station has information about the subscriber station's forward link quality metric, the base station transmits each channel 1308(i) at the minimum power determined by the power requirements of the subscriber station.

In one embodiment, channels 1302(i) are sent concurrently so each subscriber station accumulates data from all channels 1202(i) and then post-processes the accumulated data. During post-processing, each subscriber station first demodulates the control channel 1202(1) and then demodulates the MAC ID of block 1306 (1). Subscriber stations with the same MAC ID as that of module 1306(1) decode the remaining information and process sub-packets on the F-PDCH according to the collected information.

If the module 1304 indicates that there are no additional control channels 1302(i), then the determination method terminates.

If block 1304 indicates that there are m additional control channels 1118(i), the determination method continues as follows.

Subscriber stations whose MAC ID matches the partial MAC ID of module 1108(1) demodulate and decode control channel 1302(m) to obtain the MAC ID of module 1306 (m). Subscriber stations with the same MAC ID as that of module 1306(m) demodulate and decode the remaining information of control channel 1302(m) and process subpackets on the F-PDCH according to the collected information. Subscriber stations whose MAC ID does not match the MAC ID of module 1316(m) demodulate the next control channel 1302(2), as described below. Since the subscriber station has already processed the control channel 1302(m), the subscriber station that continues processing and encounters the control channel 1302(m) may stop further processing.

Subscriber stations whose MAC ID does not match the partial MAC ID of module 1308(1) demodulate the next control channel 1302(i), i.e., control channel 1302 (2). Subscriber stations with MAC IDs identical to the MAC ID of module 1316(2) decode the remaining information of control channel 1302(2) and process subpackets on the F-PDCH according to the collected information. Subscriber stations whose MAC ID matches the partial MAC ID of block 1318(2) continue processing associated with the MAC ID in block 1308. (thus, the subscriber station demodulates and decodes the control channel 1318(m-1) to obtain the MAC ID for module 1314 (m-1)).

The method is repeated until the subscriber station processes all control channels 1302(i) or finds a control channel 1302(i) with a MAC ID indicating that the control channel 1302(i) points to the subscriber station.

Coded channel allocation signaling

According to the above embodiments, the control channel structure of the present invention may use the control channel proposed by 1 xEV-DV. Therefore, the control channel of the present invention must maintain or improve the functionality of the 1xEV-DV proposed control channel.

According to the 1xEV-DV proposal, the F-PDCH subpackets are demultiplexed into a variable number of parallel stream pairs (in-phase and quadrature), and each parallel stream covered with a different 32-ary Walsh code. F-PDCH Walsh codes are assigned from the top of the list of 28 possible assigned Walsh spaces.

TABLE 1 Default F-PDCH Walsh Range List

32-element Walsh code
	31
15
	23
7
	27
11
	19
3
	29
13
	21
5
	25
9
	30
14
	22
6
	26
10
	18
2
	28
12
	20
4
	24
8

When F-PDCH is used, Walsh code assignments are used for F-PPDCCH, F-SPDCCH, and F-PDCH. In addition, for the F-PDCH, the number of such codes and the Walsh assignments for such codes are required. The number of Walsh codes used for the F-PDCH is transmitted on the F-SPDCCH. A system and method FOR signaling Walsh space assignment is disclosed in the accompanying application serial No. 60/297105, entitled "HANDLING THE WALSH space indicator FOR 1 XEV-DV", filed on 7.6.2001, assigned to the assignee of the present invention.

According to an embodiment of the invention, Walsh space is allocated according to the power of the F-SPDCCH. In one embodiment, the allocation begins with the highest power F-SPDCCH and the lowest Walsh space. Accordingly, the lowest portion of Walsh space is allocated by the highest power F-SPDCCH and the next lower portion of Walsh space is allocated by the second highest power F-PDCH until all F-SPDCCHs are exhausted. To save power and capacity of the F-SPDCCH, a single Walsh code index is not listed, and each within the F-SPDCCH includes the number of Walsh codes used.

For example, referring to table 1, if the highest F-SPDCCH assignment includes a Walsh space with Walsh codes of indices 31, 15, 23, 7, 27, and 11, the highest power F-SPDCCH includes the number 6, which is the number of Walsh codes. Similarly, if the second highest power F-SPDCCH assignment includes a Walsh space with Walsh codes of indices 19, 3, 29, 13, 21, 5, 25, the second highest power F-SPDCCH contains the number 6.

The subscriber station processes the multiple F-SPDCCH according to the embodiments disclosed above to obtain a Walsh code number from each of the multiple F-SPDCCH. The subscriber station further measures power of each of the plurality of F-SPDCCHs and sorts the number of obtained Walsh codes with the measured power. Since the subscriber station is provided with a list of Walsh spaces, the subscriber station can associate the number of each obtained Walsh code with a Walsh code.

Those of skill in the art would understand that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, circuits, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

Those of skill would further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

The various illustrative logical blocks, modules, and circuits described in connection with the embodiments disclosed herein may be implemented or performed with: a general purpose processor, a Digital Signal Processor (DSP) or other processor, an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof, to implement the functions described herein. A general purpose processor is preferably a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary processor is preferably coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an application specific integrated circuit, ASIC. The ASIC may reside in a user terminal. In the alternative, the processor and the storage medium may reside as discrete components in a user terminal.

The previous description of the preferred embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without the use of the inventive faculty. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the patent and trademark office patent file or records, but otherwise reserves all copyright rights whatsoever.

Claims (23)

1. A method for processing shared sub-packets within a communication system, comprising:

generating a first control channel comprising a parameter indicating that a sub-packet on a traffic channel is to be shared and the traffic channel; and

generating at least one second control channel, each of said at least one second control channel comprising an identification from which at least one subscriber station determines that it can share subpackets on the traffic channel and information enabling the subscriber station to demodulate the traffic channel.

2. The method of claim 1, wherein generating the first control channel includes an indicator indicating that sub-packets on a traffic channel are to be shared and a parameter of the traffic channel, comprising:

a first control channel is generated that includes an indicator indicating the number of subscriber stations that are to share the sub-packet on the traffic channel and the traffic channel unit that is shared.

3. The method as claimed in claim 2, wherein said generating at least one second control channel, each of said at least one second control channel including an identification and information enabling the subscriber station to demodulate the traffic channel, comprises:

generating at least one second control channel, each of the at least one second control channel including an identification and a number of code channels encoding a traffic channel.

4. The method of claim 1, further comprising:

the first control channel is transmitted at the power required by the subscriber station with the worst forward link quality metric and is directed to that subscriber station.

5. The method of claim 1, further comprising transmitting each of the at least one second control channel at a power required by the subscriber station to which the at least one second control channel is directed.

6. The method of claim 1, wherein generating the first control channel includes an indicator indicating that sub-packets on a traffic channel are to be shared and a parameter of the traffic channel, comprising:

a first control channel is generated that includes an indicator indicating that subpackets on the traffic channel are to be shared, a first number of sub-divisions of a traffic channel unit, and a second number of subscriber stations sharing the unit.

7. The method as claimed in claim 6, wherein said generating at least one second control channel, each of said at least one second control channel including an identification and information enabling the subscriber station to demodulate the traffic channel, comprises:

generating at least one second control channel, each of said at least one second control channel comprising an identification and a beginning subdivision of the traffic channel element.

8. A method for processing subpackets shared at a subscriber station, comprising:

demodulating the first control channel to determine whether to share subpackets on the traffic channel;

if the sub-packet on the traffic channel is to be shared, determining the number of subscriber stations sharing the sub-packet on the traffic channel and multiplexing the traffic channel according to said demodulated first control channel;

demodulating a second control channel, said channel comprising an identification of the subscriber station and information enabling the subscriber station to demodulate the traffic channel, the subscriber station determining from said identification that it can share subpackets on the traffic channel; and

if the obtained identity is identical to the identity of the subscriber station, the traffic channel is demodulated according to said multiplexing and enabling information.

9. The method of claim 8, further comprising:

if the identity is not consistent with the identity of the subscriber station and another second control channel is sent, the demodulating is repeated for the other second control channel.

10. The method of claim 8, wherein demodulating the first control channel to determine whether to share the subpackets on the traffic channel comprises:

a predetermined control channel is demodulated.

11. The method of claim 8 wherein said demodulating of the traffic channel in accordance with said determined multiplexing and enabling information if the obtained identification is consistent with the identification of the subscriber station comprises:

determining the size of the traffic channel unit and the number of code channels according to the enable information if the traffic channel unit is code multiplexed; and

to demodulate the traffic channel element.

12. The method of claim 8 wherein said demodulating the traffic channel based on the enabling information if the obtained identification is consistent with the identification of the subscriber station comprises:

determining the number of traffic channel unit subdivisions and starting subdivisions according to the enabling information if the traffic channel unit is time multiplexed; and

the traffic channel element is demodulated.

13. A method for processing shared sub-packets within a communication system, comprising:

generating a first control channel comprising a parameter indicating that a sub-packet on a traffic channel is to be shared and the traffic channel; and

generating at least one second control channel, each of said at least one second control channel comprising an identification from which at least one subscriber station determines that it can share subpackets on the traffic channel and information enabling the subscriber station to demodulate the traffic channel;

transmitting a control channel;

demodulating the received first control channel;

determining the number of subscriber stations sharing a sub-packet on a traffic channel and multiplexing the traffic channel according to said demodulated control channel;

demodulating a second control channel that includes an identification of the subscriber station and information that enables the subscriber station to demodulate the traffic channel, the subscriber station determining from the identification that it can share the sub-packet on the traffic channel; and

demodulating the traffic channel in accordance with said determined multiplexing and enabling information if the obtained identity is consistent with the identity of the subscriber station.

14. The method of claim 13, wherein generating the first control channel includes generating an indicator indicating that sub-packets on the traffic channel are to be shared and the traffic channel parameters includes:

a first control channel is generated that includes an indicator that indicates the number of subscriber stations that are to share subpackets on the traffic channel and the shared traffic channel element.

15. The method as claimed in claim 14, wherein said generating at least one second control channel, each of said at least one second control channel including an identification and information enabling the subscriber station to demodulate the traffic channel, comprises:

generating at least one second control channel, each of said at least one second control channel comprising an identification and a number of coding channels encoding traffic channel elements.

16. The method of claim 13, further comprising:

the first control channel is transmitted at the power required by the subscriber station that is the subscriber station with the worst forward link quality to which the first control channel is directed.

17. The method of claim 13, wherein each of the at least one second power channels is transmitted at a power required by the subscriber station to which the at least one second control channel is directed.

18. The method of claim 13, wherein generating the first control channel includes an indicator indicating a traffic channel to share and traffic channel parameters, the method comprising:

a first control channel is generated that includes an indicator that indicates a sub-packet on a traffic channel is to be shared, a first number of sub-divisions of a traffic channel unit, and a second number of subscriber stations sharing the unit.

19. The method as claimed in claim 18, wherein said generating at least one second control channel, each of said at least one second control channel including an identification and information enabling said subscriber station to demodulate a traffic channel, comprises:

generating at least one second control channel, each of said at least one second control channel including an identification and beginning a subdivision of the traffic channel element.

20. The method of claim 13, further comprising:

if the identity is not consistent with the identity of the subscriber station and another second control channel is sent, the demodulating is repeated for the other second control channel.

21. The method as claimed in claim 13, wherein said demodulating the control channel to determine the sub-packets to share on the traffic channel comprises:

demodulating the reserved control channel.

22. The method of claim 15 wherein demodulating the traffic channel in accordance with the predetermined multiplexing and enabling information if the obtained identification is consistent with the identification of the subscriber station comprises:

determining the size of the traffic channel unit and the number of code channels according to the enable information if the traffic channel unit is code multiplexed; and

to demodulate the traffic channel element.

23. The method of claim 18 wherein demodulating the traffic channel based on the enabling information if the obtained identification is consistent with the identification of the subscriber station comprises:

determining a number of sub-divisions of the traffic channel unit and starting the sub-divisions according to the enable information if the traffic channel unit is time-multiplexed; and

to demodulate the traffic channel element.