CN105847214B - Method and apparatus for localized and distributed distribution multiplexing and control - Google Patents

Abstract

The application relates to localized and distributed distribution multiplexing and control. Systems and methodologies are described that facilitate multiplexing of localized and distributed transmissions to reduce overhead transmission costs. According to various aspects, systems and/or methods are described that enable selection of an optimal transmission scheme to accommodate various traffic services, user capabilities, and channel characteristics.

Description

Method and apparatus for localized and distributed distribution multiplexing and control

The present application is a divisional application of the original Chinese patent application entitled "localized and distributed distribution multiplexing and control". The original application has a Chinese application number of 200780002123.7; the original application is filed on the date of No. 1-12 of 2007, and the international application number of the original application is PCT/US 2007/060516.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of U.S. provisional application serial No. 60/759,149 entitled "LOCALIZED AND DISTRIBUTED ALLOCATION MULTIPLEXING AND CONTROL (LOCALIZED AND DISTRIBUTED ALLOCATION MULTIPLEXING AND CONTROL)" filed on 13.1.2006. This application is incorporated by reference herein in its entirety.

Technical Field

The following description relates generally to wireless communications, and more particularly to a multiplexing scheme that may support flexible multiplexing for localized and distributed allocations.

Background

Wireless communication systems have become a popular means by which most people communicate worldwide. Wireless communication devices have become smaller and more powerful in order to meet consumer demands and to improve portability and convenience. The increase in processing power of mobile devices, such as cellular telephones, has led to an increase in demand for wireless network transmission systems.

A typical wireless communication network, employing frequency, time, and code division techniques, for example, comprises one or more base stations that provide a coverage area and one or more mobile (e.g., wireless) terminals that can transmit and receive data within the coverage area. A typical base station can simultaneously transmit multiple data streams for broadcast, multicast, and/or unicast services, wherein a data stream is a stream of data that can be independently received by a mobile terminal. A mobile terminal within the coverage area of that base station can receive one, more than one, or all the data streams carried by the composite stream. Likewise, a mobile terminal may transmit data to the base station or another mobile terminal.

For downlink transmissions, localized (e.g., blocky) transmissions or distributed (e.g., scattered) transmissions may be employed. Localized transmission is beneficial because it allows frequency selective scheduling. On the other hand, distributed transmission utilizes frequency diversity and is useful for high-speed users. There is a need to optimize the type of transmission employed and also to allow the number of bits transmitted during the downlink to be reduced.

Disclosure of Invention

The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

According to one aspect, a method of communication includes: receiving information about access terminal capabilities; and multiplexing localized and distributed transmissions for the access terminal according to the capabilities.

In another aspect, an apparatus comprises: a memory for storing information; a processor to execute instructions; and an optimization component that receives information about capabilities of the access terminal and multiplexes localized and distributed transmissions of the access terminal according to the capabilities.

According to another aspect, a computer-readable medium has stored thereon computer-executable instructions for performing the acts of: receiving information about access terminal capabilities; and multiplexing localized and distributed transmissions for the access terminal according to the capabilities.

In another aspect, a processor has stored thereon computer-executable instructions for performing the following acts: receiving information about access terminal capabilities; and multiplexing localized and distributed transmissions for the access terminal according to the capabilities.

In yet another aspect, a system includes: means for receiving information regarding capabilities of an access terminal; and means for multiplexing localized and distributed transmission for the access terminal according to the capabilities.

To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative aspects of the one or more aspects. These aspects are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed and the described aspects are intended to include all such aspects and their equivalents.

Drawings

Fig. 1 is an illustration of an example system that effectuates optimal downlink transmission in a wireless communication environment.

Fig. 2 is an illustration of an example transmission scheme within a wireless communication environment.

Fig. 3 is another illustration of an example transmission scheme within a wireless communication environment.

Fig. 4 is another illustration of an example scheme within a wireless communication environment.

Fig. 5 is an illustration of an example methodology that facilitates multiplexed downlink transmission in a wireless communication system.

Fig. 6 is another illustration of an example methodology that facilitates multiplexed downlink transmission in a wireless communication system.

Fig. 7 is another illustration of an example methodology that facilitates multiplexed downlink transmission in a wireless communication system.

Fig. 8 is an illustration of a wireless communication system in accordance with various aspects set forth herein.

Fig. 9 is a block diagram of a system that facilitates multiplexed downlink transmissions in accordance with mobile device capabilities.

Fig. 10 illustrates a system that provides other sector communication in accordance with one or more aspects presented herein.

Fig. 11 illustrates a system that provides for processing reverse link communications at a non-serving sector of a terminal in accordance with one or more aspects presented herein.

Fig. 12 is an illustration of a wireless communication environment that can be employed in conjunction with the various systems and methods described herein.

Detailed Description

Various embodiments are now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. It may be evident, however, that such embodiment(s) may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing one or more embodiments.

As used in this application, the terms "component," "module," "system," and the like are intended to refer to a computer-related entity, either hardware, firmware, a combination of hardware and software, or software in execution. For example, a component may be, but is not limited to being, a process running on a processor, an object, an executable, a thread of execution, a program, and/or a computer. For example, both an application running on a computing device and the computing device can be a component. One or more components may reside within a process and/or thread of execution and a component may be localized on one computer and/or distributed between two or more computers. In addition, these components can execute from various computer readable media having various data structures stored thereon. The components may communicate via local and/or remote processes such as in accordance with a signal having one or more data packets (e.g., data from one component interacting with another component in a local system, distributed system, and/or across a network such as the internet with other systems via the signal).

Further, various embodiments are described herein in connection with a mobile device. A mobile device can also be called a system, subscriber unit, subscriber station, mobile, remote station, remote terminal, access terminal, user terminal, wireless communication device, user agent, user device, or User Equipment (UE). The mobile device may be a cellular telephone, a cordless telephone, a Session Initiation Protocol (SIP) phone, a wireless local area loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device having wireless connection capability, a computing device, or other processing device connected to a wireless modem. Moreover, various embodiments are described herein in connection with a base station. A base station is used for communicating with mobile device(s) and may also refer to an access point, a node B, or some other terminology.

Moreover, various aspects or features described herein may be implemented as a method, apparatus, or article of manufacture using standard programming and/or design techniques. The term "article of manufacture" as used herein is intended to encompass a computer program accessible from any computer-readable device, carrier, or media. For example, computer-readable media can include but are not limited to magnetic storage devices (e.g., hard disk, floppy disk, magnetic strips, etc.), optical disks (e.g., Compact Disk (CD), Digital Versatile Disk (DVD), etc.), smart cards, and flash memory devices (e.g., EPROM, card, stick, key drive, etc.). In addition, various storage media described herein can represent one or more devices and/or other machine-readable media for storing information. The term "machine-readable medium" can include, without being limited to, wireless channels and various other media capable of storing, containing, and/or carrying instruction(s) and/or data.

Referring now to fig. 1, a system that effectuates optimal downlink transmission in a wireless communication environment is illustrated in accordance with various embodiments herein. Base station 100 is configured to communicate with one or more mobile devices 102. The base station 100 is comprised of an optimization component 106 that allows multiplexing of localized and distributed transmissions and a reception component 108 that receives information regarding base station capabilities, for example. Optimization component 106 allows downlink transmissions to achieve frequency diversity and mitigate overhead costs associated with the transmissions via various schemes, as described below. It should be appreciated that multiplexing for localized and distributed transmission allows for accommodation of various traffic services, user capabilities, and further allows users of one or more mobile devices 102 to take advantage of channel characteristics. Further, for example, one or more mobile devices 102 can provide information related to mobile device capabilities, estimates of downlink channel conditions, and subscriber data to optimization component 106 at base station 100. It should also be appreciated that the base station 100 may determine the percentage of high speed and low speed users, store subscriber data and information related to mobile device capabilities. This capability of the base station 100 may further allow the optimization component 106 to select an optimal multiplexing scheme based on ambient conditions.

Referring now to fig. 2, a scheme for optimizing downlink transmissions via multiplexing for localized and distributed transmissions is illustrated. At 202, a frequency band divided into three fixed localized subbands is displayed. It will be appreciated that the foregoing examples are illustrative in nature and are not intended to limit the number of localized sub-bands that can be partitioned using the various embodiments and/or methods described herein. At 204, the three localized subbands previously discussed are displayed after the distributed allocation of subcarriers is made. More particularly, distributed allocation is optionally accomplished among subcarriers 206 within localized subbands 204.

Referring to fig. 2, the illustrated multiplexing scheme operates by informing all scheduled users of their subcarrier allocations and signaling the scheduled users of the portion of the resources that have been allocated to the distributed allocation users. In the embodiment illustrated in fig. 2, the number of localized sub-bands making up the band remains unchanged regardless of the number of distributed allocations presented.

Referring now to fig. 3, a multiplexing scheme 300 is illustrated. For example, three localized sub-bands 302 are shown before the distributed resource allocation within the localized sub-bands proceeds. In this embodiment, multiplexing is accomplished by reducing the number of localized subbands 304 in the entire band rather than reducing the number of subcarriers 306 as the distributed resource allocation increases. In this manner, overhead costs associated with the uplink may be mitigated in relation to the reduction of localized sub-bands 304. It should be appreciated that as the distributed resource allocation increases, the number of localized subbands 304 decreases while the number of subcarriers 306 within a localized subband is preserved or maintained within a certain range. It should also be appreciated that as puncturing of localized subbands 304 increases due to distributed allocation, the width of the frequency band occupied by each localized subband may increase. Thus, the frequency selectivity of the localized sub-bands 304 may be reduced.

With further reference to fig. 3, information about the boundaries of localized subbands 304 and the spacing between distributed subcarriers must be conveyed to all scheduled users. A specific resource allocation is signaled on the control channel for each scheduled user and should include subband identification, starting point and spacing for distributed users, or number of tones and starting point for localized users. It should be appreciated that depending on the type of subband ID assigned, each scheduled user can know whether the transmission will be localized, distributed, or a multiplexed signal for both localized and distributed transmissions. Thus, the scheduled user will have knowledge about the interpretation associated with the control channel.

Referring to fig. 4, a multiplexing scheme 400 within a wireless communication environment is illustrated. The frequency band 402 is divided into several localized sub-bands 404. In this embodiment, the interval of the punctured distributed allocation 408 is specified for each localized sub-band 406. Thus, subcarriers may be punctured unevenly within localized subbands 406. In addition, one or more localized subbands 406 may become distributed, reducing the number of subbands 406 requiring uplink quality feedback. Furthermore, as shown above for fig. 3, a specific resource allocation is signaled on the control channel for each scheduled user. It should be appreciated that the distributed allocation is not evenly distributed across the localized sub-bands 406. For example, multiplexing scheme 400 may include one localized subband that is fully distributed, while surrounding localized subbands are localized through distributed puncturing of resources. Although multiplexing scheme 400 provides a frequency span that keeps localized sub-bands 406 constant, the number of subcarriers within localized sub-bands 406 may be reduced due to puncturing of the distributed allocations.

For the multiplexing schemes 300 and 400 illustrated in fig. 3 and 4, respectively, when the distributed allocation is significant, it is possible to reduce the number of localized subbands and thus achieve channel quality overhead reduction during uplink. As an example, if there are four localized subbands and the number of designated bits of channel quality for a subband is eight, only five bits would be needed to represent its channel quality (e.g., MCS index) if the number of localized subbands were reduced to two. On the other hand, if bandwidth overhead reduction is required to be achieved instead of power reduction, an additional three bits may be used to improve the granularity of channel quality feedback.

Referring to fig. 5-7, methodologies relating to multiplexing of localized and distributed transmissions are illustrated. While, for purposes of simplicity of explanation, the methodologies are shown and described as a series of acts, it is to be understood and appreciated that the methodologies are not limited by the order of acts, as some acts may, in accordance with the subject matter of the application, occur in different orders and/or concurrently with other acts from that shown and described herein. For example, those skilled in the art will understand and appreciate that a methodology could alternatively be represented as a series of interrelated states or events, such as in a state diagram. Moreover, not all illustrated acts may be required to implement a methodology in accordance with the claimed subject matter.

Turning specifically to fig. 5, a methodology 500 that facilitates multiplexed downlink transmission in a wireless communication system is illustrated. The method begins at 502 and determines whether a multiplexed transmission of localized and distributed transmissions is required at 504. This determination may be made, for example, based on traffic services, user capabilities, and channel characteristics. If multiplexing is not required, the method moves to 506. At 506, one of localized transmission and distributed transmission is used for downlink transmission. If a multiplexed transmission is desired, the method moves to 508 where the frequency band is partitioned into a fixed number of localized subbands. At 510, distributed allocation of resources is allowed within each localized sub-band. At 512, each scheduled user is informed of its resource allocation, and at 514, the scheduled user receives a signal indicating the portion of the localized sub-bands allocated to distributed users.

Referring now to fig. 6, an example methodology 600 that facilitates multiplexed downlink transmissions in a wireless communication system is illustrated. The method begins at 602, and at 604 it is determined whether a multiplexed transmission of localized and distributed transmissions is required. Such a determination may be made, for example, based on traffic services, user capabilities, and channel characteristics. If multiplexing is not required, the method proceeds to 606. At 606, one of localized transmission and distributed transmission is used for downlink transmission. If a multiplexed transmission is desired, the method proceeds to 608 where the frequency band is partitioned into a fixed number of localized sub-bands. At 610, the distributed allocation of subcarriers within each localized sub-band is maintained. At 612, a reduction in uplink overhead for subband quality reporting may be achieved when an increase in puncturing of distributed resources occurs within localized subbands. This reduction in uplink overhead occurs because of the corresponding reduction in the number of localized subbands caused by puncturing of the distributed resources. At 614, each scheduled user is informed of its resource allocation, and at 616, the scheduled users receive a signal indicating the portion of the localized sub-bands allocated to distributed users.

Referring now to fig. 7, a methodology 700 that facilitates multiplexed downlink transmission in a wireless communication system is illustrated. The method begins at 702, and at 704 it is determined whether a multiplexed transmission of localized and distributed transmissions is required. Such a determination may be made, for example, based on traffic services, user capabilities, and channel characteristics. If multiplexing is not required, the method proceeds to 706. At 706, one of localized transmission and distributed transmission is used for downlink transmission. If a multiplexed transmission is desired, the method proceeds to 708 where the frequency band is partitioned into a fixed number of localized subbands. At 710, an interval of distributed allocation of non-uniform puncturing within each localized sub-band is specified. At 712, the number of localized subbands in the band is reduced by transforming a number of localized subbands to distributed resources. Thus, a reduction of the channel quality overhead in the uplink is achieved. At 714, each scheduled user is notified of its resource allocation, and at 716, the scheduled user receives a signal indicating the portion of the localized subbands allocated to the distributed users.

Referring now to fig. 8, a wireless communication system 800 is illustrated in accordance with various embodiments presented herein. System 800 can comprise one or more base stations 802 (e.g., access points) in one or more sectors that receive, transmit, repeat, etc., wireless communication signals to each other and/or to one or more mobile devices 804. Those skilled in the art will appreciate that each base station 802 can comprise a transmitter chain and a receiver chain, each of which can in turn comprise a plurality of components associated with signal transmission and reception (e.g., processors, modulators, multiplexers, demodulators, demultiplexers, antennas … …). The mobile device 804 can be, for example, a cellular telephone, a smart phone, a laptop computer, a handheld communication device, a handheld computing device, a satellite radio, a global positioning system, a PDA, and/or any other device suitable for communicating on the wireless communication device 800.

Base station 802 can broadcast content to mobile devices 804 by employing a single Forward Link (FLO) technique. For example, real-time audio and/or video signals may be broadcast as well as non-real-time services (e.g., music, weather, news feeds, business, financial information … …). According to an example, content can be broadcast by the base station 802 to the mobile device 804. The mobile device 804 can receive and output such content (e.g., by employing a visual output, audio output … …). Further, FLO technology may utilize orthogonal frequency division multiple access (OFDM). Frequency division based techniques, such as OFDM, typically divide the spectrum into different channels, e.g., the spectrum may be divided into uniform blocks of bandwidth. OFDM effectively partitions the overall system bandwidth into multiple orthogonal frequency channels. In addition, an OFDM system may use time and/or frequency division multiple access to achieve orthogonality among multiple data transmissions for multiple base stations 802.

In the FLO system, it is necessary to ensure that the mobile device 804 properly receives data provided by the base station 802. For that purpose, and as described in more detail below, the FLO Test Application Protocol (FTAP) may be employed to verify the physical layer of system 800. In other words, FTAP can be employed to ensure that the mobile device 804 is properly receiving data from the base station 802. The FTAP defines a set of procedures that, when implemented by both the network and the mobile device 804, can be used for minimum performance testing for the device. For this purpose, an FTAP flow (a series of FTAP packets) may be configured and activated within the network to test specific device behavior. According to one example, each FTAP packet may carry information such as a test sequence number, a test signature, and a test data pattern. The sequence number may be a 32-bit integer obtained from a 32-bit counter, where the counter may be started at any suitable value. However, it should be appreciated that the sequence number may have any suitable number of bits, and the counter may be a counter having any suitable number of bits. The test signature may be an eight-bit pseudorandom integer derived from the use of a particular polynomial (e.g., p (x) ═ x)¹⁵+ x +1) and 15 states are obtained in a ring buffer of bits generated by the simple shift register generation program (SSRG). Again, however, the polynomial and the simple shift register generation procedure may be different, and it should be understood that appropriate variations from the SSRG and the polynomial are contemplated and intended to fall within the scope of the appended claims.

Data validation compliant with FTAP may be performed on the mobile device 804. For example, if well-known algorithms are used to generate the test data, the mobile device 804 can implement a substantially similar algorithm to verify that the received data is correct. The verification performed on the mobile device is very simple and may enable real-time reporting (e.g., the mobile device 804 may report errors over a 1x link or any other suitable link). To enable this verification, the mobile device 804 should be aware of the status of the FTAP flow. Further, the device 804 should account for erasure or coverage loss and wrap around.

Referring now to fig. 9, illustrated is a system 900 that facilitates optimal downlink transmission. System 900 can comprise a module 902 for receiving information regarding access terminal capabilities. For example, system 900 can accommodate various traffic services, user capabilities, and further allow users of one or more mobile devices to take advantage of channel characteristics, among other things. System 900 can also include a module 904 for multiplexing localized and distributed transmission for access terminals according to terminal capabilities. Module 904 can select the optimal scheme for multiplexing based on the terminal capabilities at a given time.

Fig. 10 is an illustration of a terminal or user device 1000 that provides for other sector communication in a wireless communication environment, in accordance with one or more aspects set forth herein. Terminal 1000 can include a receiver 1002 that receives a signal from, for instance, one or more receive antennas, and performs typical actions thereon (e.g., filters, amplifies, downconverts … …) the received signal and digitizes the conditioned signal to obtain samples. A demodulator 1004 can demodulate the samples and provide received pilot symbols to a processor 1006.

Processor 1006 can be a processor dedicated to analyzing information received by receiver component 1002 and/or generating information for transmission by a transmitter 1014. Processor 1006 can be a processor that controls one or more components of terminal 1000, and/or a processor that analyzes information received by receiver 1002, generates information for transmission by a transmitter 1014, and controls one or more components of terminal 1000. The processor 1006 may utilize any of the methods described herein, including those described with respect to fig. 5-7.

Additionally, terminal 1000 can include a transmission control component 1008 that analyzes received input including an acknowledgement of a successful transmission. An Acknowledgement (ACK) may be received from the serving sector and/or a neighboring sector. The acknowledgement may indicate that a previous transmission has been successfully received and decoded by one of the access points. The transmission may be resent if no acknowledgement is received, or if a Negative Acknowledgement (NAK) is received. A transmission control component 1008 may be incorporated into the processor 1006. It is to be appreciated that transmission control component 1008 can include transmission control code to perform analysis in connection with determining receipt of an acknowledgement.

Terminal 1000 can additionally include: a memory 1010 operatively coupled to the processor 1006 and operable to store information related to transmissions; a movable sector group; a method for controlling transmission; a lookup table that includes information related thereto and any other suitable information related to transmissions and the set of active sectors described herein. It will be appreciated that the data store (e.g., memories) components described herein can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. By way of illustration, and not limitation, nonvolatile memory can include Read Only Memory (ROM), programmable ROM (prom), electrically programmable ROM (eprom), electrically erasable ROM (eeprom), or flash memory. Volatile memory can include Random Access Memory (RAM), which acts as external flash memory. By way of illustration and not limitation, RAM may take many forms, such as Synchronous RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and direct memory bus RAM (DRRAM). The memory 1010 of the subject systems and methods is intended to comprise, without being limited to, these and any other suitable types of memory. Processor 1006 is connected to a symbol modulator 1012 and a transmitter 1014 that transmits the modulated signal.

Fig. 11 is an illustration of a system 1100 that facilitates other sector communication in a communication environment in accordance with various aspects. System 1100 comprises an access point 1102 with a receiver 1110 that receives signals from one or more terminals 1104 via one or more receive antennas 1106 and transmits to the one or more terminals 1104 via a plurality of transmit antennas 1108. Terminals 1104 can include those terminals supported by access point 1102 as well as terminals 1104 supported by neighboring sectors. In one or more aspects, receive antennas 1106 and transmit antennas 1108 can be implemented using a single antenna group. Receiver 1110 can receive information from receive antennas 1106 and is operatively associated with a demodulator 1112 that demodulates received information. Those skilled in the art will appreciate that receiver 1110 may be, for example, a rake receiver (e.g., one such technique … … that uses multiple baseband correlators to individually process multipath signal components), an MMSE-based receiver, or some other receiver suitable for separating out the terminals assigned thereto. According to various aspects, multiple receivers may be employed (e.g., one receiver per antenna), and the receivers may communicate with each other to provide improved estimates of user data. Demodulated symbols are analyzed by a processor 1114, which is similar to the processor described above with reference to fig. 10 and is coupled to a memory 1116 that stores information related to the terminal, assigned resources associated with the terminal, and so on. The receiver output for each antenna can be jointly processed by receiver 1110 and/or processor 1114. A modulator 1118 may multiplex the signal for transmission by a transmitter 1120 through transmit antennas 1108 to terminals 1104.

Access point 1102 further includes a terminal communication component 1122 that can be a processor separate from or integral to processor 1114. Terminal communication component 1122 can obtain resource assignment information for terminals supported by neighboring sectors. In addition, terminal communication component 1122 can provide assignment information to neighboring sectors of terminals supported by access point 1102. Assignment information can be provided via backhaul signaling.

Based on the information regarding the assigned resources, terminal communication component 1122 can direct detection of transmissions from terminals supported by neighboring sectors and decoding of received transmissions. Memory 1116 may maintain packets received from the terminals prior to receiving assignment information necessary to decode the packets. Terminal communication component 1122 can also control transmission and reception of acknowledgements indicating successful receipt and decoding of transmissions. It is to be appreciated that terminal communication component 1122 can include transmission analysis code that performs utility-based control in connection with assigning resources, identifying terminals for soft handoff, decoding transmissions, and the like. The terminal analysis code can utilize artificial intelligence based methods that can be combined with probabilistic determinations and/or statistical-based determinations that perform inference and/or in combination with optimizing terminal performance.

Fig. 12 shows an exemplary wireless communication system 1200. The wireless communication system 1200 depicts one terminal and two access points for sake of brevity. It is to be appreciated, however, that the system can include one or more access points and/or one or more terminals, wherein additional access points and/or terminals can be substantially similar or different for the exemplary access point and terminal described below. In addition, it is to be appreciated that the access point and/or the terminal can employ the systems (fig. 1-4 and 8-11) and/or methods (fig. 5-7) described herein.

Fig. 12 shows a block diagram of a terminal 1204, a serving access point 1202X supporting the terminal 1204, and a neighboring access point 1202Y in a multiple access multi-carrier communication system 1200. At access point 1202X, a Transmit (TX) data processor 1214 receives traffic data (i.e., information bits) from a data source 1212 and signaling and other information from a controller 1220 and a scheduler 1230. For example, scheduler 1230 may provide assignments of carriers for the terminals. Additionally, memory 1222 may maintain information about current or previous assignments. TX data processor 1214 encodes and modulates the received data using multi-carrier modulation (e.g., OFDM) to provide modulated data (e.g., OFDM symbols). A transmitter unit (TMTR)1216 then processes the modulated data to generate a downlink modulated signal, which is then transmitted from an antenna 1218.

The scheduler can provide assignment information to access point 1202Y prior to transmission of the assignment information to terminal 1204. The assignment information may be provided via backhaul signaling (e.g., T1 line) 1210. Alternatively, assignment information can be provided to access point 1202Y after transmission to terminal 1204.

At terminal 1204, the transmitted and modulated signal is received by an antenna 1252 and provided to a receiver unit (RCVR) 1254. Receiver unit 1254 processes and digitizes the received signal to provide samples. A Received (RX) data processor 1256 then demodulates and decodes the samples to provide decoded data, which may include recovered traffic data, messages, signaling, and so on. The traffic data can be provided to a data sink 1258 and the carrier assignment information for terminal 1204 can be provided to a controller 1260.

Controller 1260 directs data transmission on the uplink using the particular carrier that has been assigned to terminal 1204 and that has been indicated in the received carrier assignment. Memory 1262 may maintain information regarding assigned resources (e.g., frequency, time, and/or code) and other related information.

For terminal 1204, a TX data processor 1274 receives traffic data from a data source 1272 and signaling and other information from controller 1260. The various types of data are coded and modulated by TX data processor 1274 using the assigned carriers and further processed by a transmitter unit 1276 to generate an uplink modulated signal that is then transmitted from antenna 1252.

At access points 1202X and 1202Y, the transmitted and modulated signals from terminal 1204 are received by antenna 1218, processed by a receiver unit 1232, and demodulated and decoded by a RX data processor 1234. The transmitted signal can be decoded and provided to neighboring access point 1202Y based on the assignment information generated by serving access point 1202X. In addition, access points 1202X and 1202Y can generate an Acknowledgement (ACK) that can be provided to another access point (1202X or 1202Y) and/or to terminal 1204. The decoded signal may be provided to a data sink 1236. Receiver unit 1232 may estimate the received signal quality (e.g., the received signal-to-noise ratio (SNR)) for each terminal and provide this information to controller 1220. RX data processor 1234 provides the recovered feedback information for each terminal to controller 1220 and scheduler 1230.

Scheduler 1230 uses the feedback information to perform functions such as (1) selecting a set of terminals for data transmission on the reverse link and (2) assigning carriers to the selected terminals. The carrier assignments for the scheduled terminals are then transmitted to the terminals on the forward link.

The techniques described herein may be implemented in various ways. For example, these techniques may be implemented in hardware, software, or a combination thereof. For a hardware implementation, the processing units used for these techniques, e.g., controllers 1220 and 1260, TX and RX processors 1214 and 1234, etc., may be implemented within one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), processors, controllers, micro-controllers, microprocessors, other electronic units designed to perform the functions described herein, or a combination thereof.

For a software implementation, the techniques described herein may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. The software codes may be stored in memory units and executed by processors. The memory unit may be implemented within the processor or external to the processor, in which case it can be communicatively coupled to the processor using various means as is known in the art.

The examples described above include one or more aspects. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the aforementioned aspects, but one of ordinary skill in the art may recognize that many further combinations and permutations of various aspects are possible. Accordingly, the aspects are intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims. Furthermore, to the extent that the term "includes" is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term "comprising" as "comprising" is interpreted when employed as a transitional word in a claim.

Claims (29)

1. A method for wireless communication, comprising:

receiving information about access terminal capabilities;

determining percentages of high speed and low speed users; and

selecting an optimal multiplexing scheme to multiplex localized and distributed transmissions in communications to the access terminal on a downlink channel according to the access terminal capabilities and the percentages of the high and low speed users,

assigning a type of subband ID to inform each respective scheduled user whether the transmission will be a localized, distributed, or multiplexed signal of both localized and distributed transmissions, such that the scheduled user is aware of an interpretation of an associated control channel,

wherein prior to said multiplexing, it is determined whether coordination between localized and distributed transmissions is required, and if so, a distributed allocation operation is performed among the subcarriers within the localized sub-bands,

wherein the optimal multiplexing scheme facilitates optimized frequency diversity by informing scheduled users of their respective subcarrier allocations and signaling to the scheduled users the portions of resources that have been allocated to distributed users, and

wherein a particular resource allocation is signaled on a respective control channel for each scheduled user, and includes the subband ID, starting point and spacing for the distributed users, or starting point and number of tones for localized users.

2. The method of claim 1, wherein the multiplexing is a function of an estimate of downlink channel conditions.

3. The method of claim 1, wherein the multiplexing is a function of subscriber data.

4. The method of claim 1, wherein the multiplexing is a function of the percentage of high and low speed users.

5. The method of claim 1, wherein the number of localized sub-bands that make up a frequency band remains unchanged regardless of the number of distributed allocation results present.

6. The method of claim 1, wherein multiplexing is based on decreasing the number of subcarriers as a result of distributed allocation of resources increases.

7. The method of claim 1, wherein multiplexing is based on reducing the number of localized subbands in the entire band.

8. The method of claim 7, wherein as the result of the distributed allocation of resources increases, the number of localized subbands decreases and the number of subcarriers within a localized subband is preserved and kept within a certain range.

9. The method of claim 7, further comprising communicating information about boundaries of the localized subbands and spacing between distributed subcarriers to scheduled users.

10. The method of claim 1, wherein a frequency band is partitioned into localized subbands, and an interval of punctured distributed allocation results is specified for each localized subband.

11. The method of claim 10, wherein one or more localized subbands are distributed to reduce a number of subbands requiring uplink quality feedback.

12. The method of claim 1, wherein the distributed distribution results are unevenly distributed across the localized subbands.

13. The method of claim 12, wherein the multiplexing includes one or more localized sub-bands that are all distributed, while surrounding localized sub-bands are one of localized by distributed puncturing of resources and not localized by distributed puncturing of resources.

14. The method of claim 13, wherein the multiplexing provides a frequency span that keeps the localized subbands constant.

15. The method of claim 1, wherein as distributed allocation results increase, the number of localized subbands is decreased to facilitate achieving a reduction in channel quality overhead during uplink.

16. The method of claim 15, wherein an additional three bits are employed to improve granularity of channel quality feedback in the event that bandwidth overhead reduction is required to be achieved instead of power reduction.

17. An apparatus for wireless communication, comprising:

a memory for storing information;

a processor for executing instructions; and

an optimization component that receives information about access terminal capabilities, determines percentages of high speed and low speed users, and selects an optimal multiplexing scheme to multiplex localized and distributed transmissions in communications to the access terminal on a downlink channel based on the access terminal capabilities and the percentages of high speed and low speed users,

wherein the apparatus is configured to allocate a type of subband ID to inform each respective scheduled user whether the transmission will be a localized, distributed, or a multiplexed signal of both localized and distributed transmissions, such that the scheduled user is aware of an interpretation of an associated control channel,

wherein the optimization component is configured to determine whether coordination between localized and distributed transmissions is required prior to the multiplexing, and if so, the optimization component is configured to perform a distributed allocation operation among subcarriers within a localized sub-band,

wherein the optimization component is configured to perform the optimal multiplexing scheme to facilitate optimized frequency diversity by notifying scheduled users of their respective subcarrier allocations and signaling to the scheduled users portions of resources that have been allocated to distributed users, and

wherein the optimization component is configured to signal a specific resource allocation on a respective control channel for each scheduled user, and the specific resource allocation includes the subband ID, a starting point and spacing for the distributed users, or a starting point and number of tones for localized users.

18. The apparatus of claim 17, wherein the optimization component performs the multiplexing based on an estimate of downlink channel conditions.

19. The apparatus of claim 17, wherein the optimization component performs the multiplexing based on subscriber data.

20. The apparatus of claim 17, wherein the optimization component performs the multiplexing according to a percentage of the high-speed and low-speed users.

21. The apparatus of claim 17, wherein the optimization component performs the multiplexing in accordance with reducing a number of localized subbands in an entire frequency band.

22. An apparatus for wireless communication, comprising:

means for receiving information regarding access terminal capabilities;

means for determining a percentage of high speed and low speed users; and

means for selecting an optimal multiplexing scheme to multiplex localized and distributed transmissions in communications to the access terminal on a downlink channel according to the access terminal capabilities and the percentages of the high speed and low speed users,

means for assigning a type of subband ID to inform each respective scheduled user whether the transmission will be localized, distributed, or a multiplexed signal of both localized and distributed transmissions to let the scheduled user know about an interpretation of an associated control channel,

wherein prior to said multiplexing, it is determined whether coordination between localized and distributed transmissions is required, and if so, a distributed allocation operation is performed among the subcarriers within the localized sub-bands,

wherein the optimal multiplexing scheme facilitates optimized frequency diversity by informing scheduled users of their respective subcarrier allocations and signaling to the scheduled users the portions of resources that have been allocated to distributed users, and

wherein a particular resource allocation is signaled on a respective control channel for each scheduled user, and includes the subband ID, starting point and spacing for the distributed users, or starting point and number of tones for localized users.

23. The apparatus of claim 22, wherein the multiplexing is a function of an estimate of downlink channel conditions.

24. The apparatus of claim 22, wherein the multiplexing is a function of subscriber data.

25. The apparatus of claim 22, wherein the multiplexing is a function of the percentage of high speed and low speed users.

26. The apparatus of claim 22, wherein multiplexing is based on decreasing the number of subcarriers as a result of distributed allocation of resources increases.

27. The apparatus of claim 22, wherein multiplexing is based on reducing a number of localized subbands in an entire band.

28. The apparatus of claim 22, further comprising means for communicating information regarding boundaries of the localized subbands and spacing between distributed subcarriers to scheduled users.

29. A computer readable medium storing computer code executable by a processor to perform the steps of:

receiving information about access terminal capabilities;

determining percentages of high speed and low speed users; and

selecting an optimal multiplexing scheme to multiplex localized and distributed transmissions in communications to the access terminal on a downlink channel according to the access terminal capabilities and the percentages of the high and low speed users,

assigning a type of subband ID to inform each respective scheduled user whether the transmission will be a localized, distributed, or multiplexed signal of both localized and distributed transmissions, such that the scheduled user is aware of an interpretation of an associated control channel,

wherein prior to said multiplexing, it is determined whether coordination between localized and distributed transmissions is required, and if so, a distributed allocation operation is performed among the subcarriers within the localized sub-bands,

wherein the optimal multiplexing scheme facilitates optimized frequency diversity by informing scheduled users of their respective subcarrier allocations and signaling to the scheduled users the portions of resources that have been allocated to distributed users, and

wherein a particular resource allocation is signaled on a respective control channel for each scheduled user, and includes the subband ID, starting point and spacing for the distributed users, or starting point and number of tones for localized users.

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