RU2432690C2 - Cdma wireless communication system - Google Patents

Abstract

FIELD: information technology.

SUBSTANCE: system wherein a CDMA segment at each access point consists of multiple sub-segments a three-frame transmission time interval (TTI) with eight retransmissions is used for data transmission. The access point not only specifies interlaces to be used for data transmission but also assigns packet start interlaces for particular access terminals. An auxiliary pilot channel R-AuxPICH is transmitted by an access terminal along with CDMA data on a reverse link. The ratio of R-AuxPICH to R-PICH is varied based on ACK/NACK feedback. A reverse link activity bit (RAB) which can be used as an emergency load-control mechanism for non-QoS flows is also disclosed.

EFFECT: high accuracy of transmitting information.

45 cl, 11 dwg

Description

Cross reference to related application (s )

This application claims the priority of provisional applications for the grant of US patent No. 60 / 840,109, filed August 25, 2006 and entitled "CDMA WIRELESS COMMUNICATION SYSTEMS", No. 60 / 841,360, filed August 30, 2006 and entitled "CDMA WIRELESS COMMUNICATION SYSTEMS" and No. 60 / 828,823, filed October 10, 2006, entitled "CDMA WIRELESS COMMUNICATION SYSTEMS", the materials of which are fully incorporated herein by reference.

State of the art

This document generally relates to various aspects of the performance of CDMA communications in wireless communication systems.

Wireless communication systems are widely deployed to provide various types of information transfer, such as speech, data, video, etc. These systems can be multiple access systems capable of supporting information exchange with multiple access terminals by sharing available system resources (e.g., bandwidth and transmit power). Examples of such multiple access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access systems (OFDMA) or hybrids comprising at least two of these systems. Typically, a wireless communication system comprises several base stations, each base station communicating with a mobile station using a forward link, and each mobile station (or access terminal) communicating with a base station using a reverse link.

Simple radio networks that transmit data have now evolved to wireless systems that transmit voice or even video signals. As a result, user needs also increased in terms of the amount of data transferred, bandwidth and power, etc. Therefore, despite the successes made in such communication systems, various aspects of these systems must be further developed to respond to growing needs. This could include improvements in various aspects, such as communication quality, energy efficiency, optimal use of radio equipment, bandwidth, etc.

Disclosure of invention

The following is a simplified summary of the claimed subject matter to provide a basic understanding of some aspects of the claimed subject matter. This entity is not a comprehensive review of the claimed subject matter. It is not intended to identify key or important elements of the claimed subject matter, nor to outline the scope of the claimed subject matter. Its sole purpose is to present some concepts of the claimed subject matter in a simplified form as an introduction to the more detailed description that is presented later.

A communication method, according to various aspects described herein, is provided for an access terminal (AT) that can transmit a CDMA data signal and to which a CDMA control subsegment is allocated, together with other ATs that transmit OFDM data signals, and one or more traffic subsegments CDMA for data transfer. The CDMA segment at each access point (AP) consists of a plurality of sub-segments, which can be allocated in a predetermined or dynamic manner in time and / or frequency, configured by the network.

In one aspect, a transmission time interval (TTI) of three frames with eight retransmissions is used to transmit CDMA data. A CDMA segment is defined in such a way that it is transmitted in at least three physical (PHY) frames, for example, one packet is transmitted in parts in three PHY frames. In accordance with other aspects, a predetermined H-ARQ transmission of CDMA data is extended by the number of frames, for example, of the three that make up the TTI, which is available. Moreover, the AP can also establish interlaces from which a packet can begin during configuration for a specific AT.

In some aspects, auxiliary pilots may be transmitted in frames carrying data transmissions over the same bandwidth as data transmissions. In various aspects, the encryption of the auxiliary feedback pilot channel (R-AuxPich) may be a function of both the rate indication and the transmission index. This allows the AT to signal changes in speed for CDMA reverse transmission with minimal loss.

In another aspect, an R-AuxPich (reverse auxiliary pilot channel) is transmitted when CDMA data is present, and ATs for transmitting OFDM data may be excluded. Thus, R-AuxPich is used as a channel estimation pilot for CDMA transmissions, like an AP. In various aspects, the ratio of CDMA traffic power to R-AuxPich is fixed based on the packet format. The ratio of R-AuxPich to R-PICH may vary based on ACK / NACK feedback. In accordance with various aspects, this is achieved by setting the final goal, step size of the step up and step size of the step down during configuration.

In additional aspects, a reverse link peer-to-peer discharge (RAB) that indicates whether a load (indicated by thermal noise excess (RoT) or some other measurement) exceeds a predetermined threshold value in a particular sector can be used as a mechanism emergency load control. It can be used to determine which streams are allowed to transmit data over a CDMA traffic segment in each physical frame. In a further aspect, the RAB bit value for each terminal may be set during configuration.

The following description and the annexed drawings set forth in detail certain illustrative aspects of the claimed subject matter. These aspects, however, indicate only some of the various ways in which the principles of the claimed subject matter can be used, and the claimed subject matter is intended to include all such aspects and their equivalents. Other advantages and features of the claimed subject matter will become apparent from the following detailed description of the claimed subject matter when considered in conjunction with the drawings.

Brief Description of the Drawings

FIG. 1 illustrates a wireless multiple-access communication system in accordance with various aspects set forth herein.

FIG. 2 illustrates a block diagram of an embodiment of an AP and two ATs in a multi-carrier multiple access communication system.

FIG. 3 illustrates a circuit diagram of an AP in accordance with one aspect.

FIG. 4A illustrates a retransmission timeline for an interleaved H-ARQ structure in accordance with one aspect.

FIG. 4B illustrates an aspect in which an AP defines interlaces to be used for CDMA data for an AT and assigns initial packet interleaving.

FIG. 4C illustrates a schematic diagram of an example of a physical frame used to transmit CDMA traffic data.

FIG. 5 is a schematic drawing of an embodiment for transmitting data from an AT in accordance with one aspect.

FIG. 6 illustrates a flowchart of a data transmission method that can be used to reduce the need for an RRI channel.

FIG. 7 is a flowchart that relates to another aspect providing a power control loop for various reverse link channels in a communication system.

FIG. 8 relates to a method 800 for tuning power of various control channels in a communication system based on ACK / NACK feedback.

FIG. 9 illustrates a method that utilizes single bit reverse link (RAB) activity discharge as an emergency load control mechanism.

The implementation of the invention

The claimed object of the invention is further described with reference to the drawings, in which the same reference numbers are used to refer to the same elements throughout the description. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the claimed subject matter. However, it is obvious that the claimed subject matter of the invention can be put into practice without these special details. In other cases, well-known structures and devices are illustrated in block diagram form in order to facilitate describing the claimed subject matter.

Various embodiments will now be described with reference to the drawings, in which like reference numbers 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 features. However, it may be obvious that such an embodiment (s) of implementation can be practiced without these specific details. In other instances, well-known structures and devices are illustrated in block diagram form in order to facilitate describing one or more embodiments. When used in this application, the terms "component", "module", "system", etc. are intended to refer to an object associated with the use of a computer, or hardware, firmware, a combination of hardware and software, software, or software during execution. For example, a component may be, but is not limited to, a process running on a processor, a processor, an integrated circuit, an object, an executable, a thread of execution, a program, and / or a computer. By way of illustration, both an application running on a computing device and a computing device can be a component. One or more components may be in the process and / or thread of execution, and the component may be located on one computer and / or distributed between two or more computers. In addition, these components can be executed from various computer-readable media having various data structures recorded thereon. Components can interact through local and / or remote processes, for example, in accordance with a signal having one or more data packets (for example, data from one component interacting with another component in a local system, distributed system and / or over a network, such like the Internet, with other systems through a signal).

In addition, various embodiments are described herein in connection with a wireless terminal and / or base station. A wireless terminal may refer to a device providing a user with the ability to transmit voice and / or data. The wireless terminal may be connected to a computing device, such as a laptop computer or desktop computer, or it may be a self-contained device, such as a personal digital assistant (PDA). A wireless terminal may also be called a system, subscriber module, subscriber station, mobile station, mobile, remote station, access point, remote terminal, access terminal, user terminal, user agent, user device, or user equipment. A wireless terminal may be a subscriber station, a wireless device, a cellular telephone, a PCS telephone, a wireless telephone, a Session Initiation Protocol (SIP) telephone, a Wireless Local Area Communication System (WLL) station, a personal digital assistant (PDA), and a handheld device with wireless capability connection, or other processing device connected to the wireless modem. A base station (eg, an access point) may refer to a device in some access network that exchanges information over the air interface through one or more sectors with wireless terminals. The base station can act as a router between the wireless terminal and the rest of the access network, which can include an Internet Protocol (IP) network by converting the received frames of the radio interface to IP packets. The base station also coordinates tag management for the radio interface. In addition, various features or features described herein may be implemented as a method, device, or product using standard software and / or technical techniques. The term "product" when used in this document is intended to include a computer program accessible from any computer-readable device, carrier or media. For example, computer-readable media may include, but are not limited to, magnetic storage devices (eg, hard disk, floppy disk, magnetic tapes, ...), optical discs (eg, compact disc (CD), digital versatile disk (DVD), ... ), smart cards, and flash memory devices (such as a memory card, flash drive, ...).

Various embodiments will be presented based on systems, which may include a number of devices, components, modules, and the like. It must be understood and taken into account that various systems may include additional devices, components, modules, etc. and / or may not include all of these devices, components, modules, etc., discussed in connection with the drawings. A combination of these approaches may also be used.

The word “exemplary” is used herein to mean “serving as an example, case, or illustration.” Any embodiment or execution described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments or executions. The word “tapping” is used in this document to indicate that the destination device (access point or access terminal) receives and processes data received on a given channel.

FIG. 1 illustrates a wireless communication system 100 with multiple access points (APs) and multiple terminals 120. A base station is a station that communicates with a terminal. A base station may also be called and may contain some or all of the functionality of an access point, Node B and / or some other network entity. Each access point 110 provides a radio area for a particular geographic area 102. The term "cell" may refer to an access point and / or its service area, depending on the context in which the term is used. To increase system capacity, the service area of the access terminal can be divided into many smaller areas, for example, three small areas 104a, 104b and 104c. Each small area is served by a corresponding base station transceiver subsystem (BTS). The term "sector" may refer to an AP and / or its service area, depending on the context in which the term is used. For sectorized cells, APs for all sectors of this cell are typically combined at the base station for that cell. The signaling techniques described in this document can be used for a system with sectorized cells, as well as systems with non-sectorized cells. For simplicity, in the following description, the term "base station" is used generally for a station that serves a sector, as well as for a station that serves a cell.

Terminals 120 are typically dispersed throughout the system, and each terminal may be stationary or mobile. A terminal may also be called and may contain some or all of the functionality of a mobile station, user equipment, and / or some other device. The terminal may be a wireless device, a cell phone, a personal digital assistant (PDA), a wireless modem card, etc. The terminal can interact with zero, one or multiple base stations on the forward and reverse links at any given time.

For a centralized architecture, a system controller 130 connects to the AP 110 and provides coordination and management of these base stations. System controller 130 may be a single network entity or a collection of network entities. For a distributed architecture, APs can communicate with each other as needed.

In some aspects, a system can support multiple protocols, for example, CDMA and OFDMA, which can be used alternately for reverse and forward transmission, or for only one or the other. In addition, in an OFDMA communication system, one or more ATs may support a CDMA reverse link, along with or instead of an OFDM reverse link.

FIG. 2 illustrates a block diagram 200 of an embodiment of an AP 110x and two ATs 120x and 120y in a multi-carrier multiple access communication system 100. On the AP 110x, the transmit (TX) data processor 514 receives traffic data (i.e., information bits) from the data source 512, and signaling information and other information from the controller 520 and the scheduler 530. For example, the controller 520 may provide power control (PC) commands, which are used to adjust the transmit power of active ATs, and the scheduler 530 may provide carrier allocation for the ATs. These various types of data can be sent on different transport channels. Transmit data processor 514 encodes and modulates received data using multi-carrier modulation (eg, OFDM) to provide modulated data (eg, OFDM symbols). Transmitter module (TMTR) 516 then processes the modulated data to generate a downlink modulated signal, which is then transmitted from antenna 518. Furthermore, memory 522 can store information regarding current or previous distributions and / or power levels.

At each of the ATs 120x and 120y, the transmitted and modulated signal is received using an antenna 552 and provided to the receiver module 554 (RCVR). Receiver module 554 processes and digitizes the received signal to obtain samples. A received (RX) data processor 556 then demodulates and decodes the samples to provide decoded data, which may include recovered traffic data, messages, signaling information, etc. Traffic data may be provided to the data receiver 558, and carrier allocation and PC commands sent to the terminal are provided to the controller 560. A memory device 562 may be used to store received cards and other information facilitating the operation of the terminal. A controller 560 directs uplink data transmission using resources that are allocated to the terminal and indicated in the received allocation.

A controller 520 directs downlink data transmission using resources that are allocated to the terminal. The controller 520 further admits signature deletion packets when there is no current data to transmit, and also expects the allocation of allocated resources.

For each active terminal 120, the transmit data processor 574 receives traffic data from the data source 572, and signaling information and other information from the controller 560. For example, the controller 560 may provide information indicating channel quality information, required transmit power, maximum transmit power, or the difference between the maximum and required transmission powers for the terminal. Various types of data are encoded and modulated by the transmitted data processor 574 using dedicated carriers and further processed by the transmitter module 576 to generate an uplink modulated signal, which is then transmitted from the antenna 552.

At AP 110x, the transmitted and modulated signals from the AT are received by the antenna 518, processed by the receiver module 532, and demodulated and decoded by the received data processor 534. Decoded signals may be provided to data receiver 536. The receiver module 532 can evaluate the quality of the received signal (eg, received signal-to-noise ratio (SNR)) for each terminal and provide this information to the controller 520. The controller 520 can then extract the PC commands for each terminal, so that the quality of the received signal for the terminal is maintained acceptable range. The received data processor 534 provides the controller 520 and the scheduler 530 with the restored feedback information (e.g., the required transmit power) for each terminal.

Scheduler 530 may instruct controller 520 to hold resources. This indication is provided if more data is planned for transmission. For the AT 120x, the controller 560 can determine whether to hold resources. In some features, the controller 520 may execute commands that provide the functionality of the scheduler 530.

As shown in FIG. 3, the access point 300 may comprise a main module 250 (MU) and a radio communication module (RU) 275. The MU 250 includes digital baseband access point components. For example, the MU 250 may include a baseband component 205 and a digital intermediate frequency (IF) processing module 210. The IF digital processing module 210 digitally processes the radio channel data at an intermediate frequency by performing functions such as filtering, channel separation, modulation, etc. RU 275 includes parts of analog radio communications at an access point. As used herein, the radio module is part of an analog radio in an access point or other type of transceiver station with direct or indirect connection to a mobile switching center or corresponding device. A radio communication module typically serves a particular sector in a communication system. For example, RU 275 may include one or more receivers 230 connected to one or more antennas 235a-t for receiving radio communications from mobile subscriber modules. In one aspect, one or more power amplifiers 282a-t are coupled to one or more antennas 235a-t. An analog-to-digital (A / D) converter 225 is connected to the receiver 230. The analog-to-digital converter 225 converts the analog radio received by the receiver 230 into digital input data for transmission to the baseband component 205 through the digital IF processing module 210. RU 275 may also include one or more transmitters 220 connected to either one or different antennas 235 for transmitting radio communications to access terminals. A digital-to-analog (D / A) converter 215 is connected to the transmitter 220. The digital-to-analog converter 215 converts the digital communications received from the baseband component 205 through the digital IF processing module 210 into analog output data for transmission to the mobile subscriber modules. In some embodiments, a multiplexer 284 is used to multiplex multi-channel signals and multiplex a number of signals, including a speech signal and a data signal. The central processor 280 is connected to the main module 250 and the radio communication module 275 to control various processing, which includes the processing of a speech signal or data signal.

This document describes one or more aspects of a wireless communication system that supports both duplex and half duplex FDD (frequency duplex separation) and TDD (time division duplex) operation modes, with support for scalable bandwidth. However, this should not be an example, and other modes may also be supported, in addition to or instead of previous modes. Additionally, it should be noted that the ideas and approaches in this document do not have to be used in conjunction with any other ideas or approaches described in this document. The various features discussed in this document may also be related to UMB (Ultra Wideband Mobile Communication), which is an OFDMA (Orthogonal Frequency Division Multiple Access) mobile solution that provides mobile broadband services to various devices ranging from computing platforms to mobile handsets. It employs signaling and control mechanisms that promote techniques like MIMO, etc. Therefore, this technology can provide mobile broadband qualification, basically similar to the broadband access associated with terrestrial networks.

In one aspect of an AT that can transmit a CDMA data signal, a CDMA control subsegment is allocated along with other ATs that transmit OFDM data signals and one or more CDMA traffic subsegments for data transmission. For example, in a UMB system, a CDMA subsegment consists of a continuous portion of the bandwidth in a frame that periodically occurs through each predetermined number of physical frames. One or more sub-segments may be allocated to one access terminal to transmit a control channel. These are known as CDMA control sub-segments. Moreover, the access terminal may also be allocated one or more CDMA subsegments to transmit CDMA traffic, which are known as CDMA traffic subsegments. The many CDMA subsegments used for traffic may or may not be the same as the many CDMA subsegments used for control. Typically, the CDMA segment in each AP contains a plurality of sub-segments that can be allocated in a predetermined or dynamic manner in time and / or frequency configured by the network. The allocation of CDMA sub-segments is flexible, it can be shared across the entire network or network sections and the same for all ATs, or it provides partial overlap across neighboring APs. Moreover, the APs are also allowed to have only control sub-segments (i.e., no traffic sub-segments) for all ATs. The control sub-segment may be scheduled, or bypassed, on top of the traffic sub-segments in the OFDM reverse link. Moreover, in some aspects, auxiliary pilot signals may be transmitted in frames carrying data transmissions over the same bandwidth as data transmission. Data frames typically comprise a frame control field, an address field, a frame body, and a frame check sequence, among other values.

In one aspect of reverse link (RL) data transmission, CDMAs support automatic repeat request (ARQ) or hybrid automatic repeat request (H-ARQ) for packet retransmission. ARQ is a method of error control in data transmission, in which the receiver sends an acknowledgment to the transmitter to indicate proper reception of the data frame. Hybrid ARQ (H-ARQ) is a type of ARQ error control method in which error detection information (e.g., cyclic redundancy check code) and error correction code, e.g., turbo code, are encoded into a data block. When such an encoded data block is received, error correction codes can be extracted to correct transmission errors and obtain the correct data frame. If all transmission errors are not corrected, then the receiver may request a retransmission in the same ARQ way.

FIG. 4A illustrates a retransmission timeline for an interleaved H-ARQ structure in accordance with one aspect. Data transmission is usually organized in frames of fixed duration, which may be called TTI (transmission time interval). Each frame may consist of a specific number of time slots. Typically, ATs in a cell can be synchronized both at the frame level and at the slot level. To provide H-ARQ-dependent processing time for AN and AT, a three-interleaving structure can be used for FL and RL. In accordance with one aspect, interleaving may comprise multiple frames, such that each frame is separated by seven physical frames and each physical frame contains 8 OFDM symbols.

H-ARQ is typically implemented by forming a frame with transmission data encoded by an error correction code and an error detection code. In accordance with one aspect, a transmission time interval (TTI) of one frame length with eight retransmissions is used to transmit CDMA data. This may be the same as OFDM data transmitted over the same system. However, such an interleaved structure can lead to poor statistical compaction among users, and a link budget that takes into account gains and losses from the transmitter is poor. These disadvantages can be overcome by using an interleaving structure that has packets shared between multiple equidistant frames. Accordingly, a three-frame TTI with eight retransmissions can be used for data transmission, as illustrated in FIG. 4A. In this aspect, a CDMA segment is defined in such a way that it is transmitted in at least three physical frames, for example, one packet is transmitted in parts in three physical frames. In other features, a predetermined H-ARQ transmission of CDMA data is expanded by the number of frames, for example, of the three that make up the TTI, which is available. The scheduler can maintain granularity in the distribution of CDMA traffic, while providing the flexibility to improve the statistical aggregation discussed in this document.

For a given AT, the AP may indicate a plurality of interlaces available for CDMA data. In addition, the AP may also indicate interlaces with which the packet may begin during configuration, by distribution or other transmission. For example, there may be up to two interlaces per user valid for transmitting CDMA data. In accordance with the timeline illustrated in FIG. 4A, the AP specifies that interlaces 0, 1, and 2 should be used for CDMA data (for this AT), and packet transmission should begin at interlace 0 and span interlaces 0, 1, and 2. ACK (acknowledgment) is transmitted from AT to AP in interleaving 5, and subsequently the data is repeated in retransmissions spanning interlaces 8, 9 and 10. FIG. 4B illustrates an aspect in which the AP specifies that interlaces 1 and 2 need to be used for CDMA data (for this AT), and a packet start interlace is assigned to 0. Therefore, packet transmission spans interleaves 1 and 2. In general, an AP can specify two such interleaving "start packet". Two interleaving of the beginning of the packet can be spaced at least three frames. ACK resources (acknowledgment) are allocated to ATs corresponding to each interlace at which it can start a packet, as shown in FIG. 4A and FIG. 4B. In general, for an initial interleaving k, an AT packet may span one or more interlaces k, k + 1 and k + 2 based on interlaces allocated by AT for its CDMA traffic. An extension of three physical frames provides improved statistical multiplexing between users, as well as increased transmitter gains, resulting in a better link budget for the same packet sizes. In addition, it provides AP flexibility in setting variable TTI sizes for different ATs based on various criteria, such as bandwidth requirements.

FIG. 4C illustrates an embodiment of a physical frame used to transmit CDMA traffic data as previously described. In accordance with this aspect, each physical frame is composed of 8 OFDM symbols.

FIG. 5 relates to an embodiment for transmitting data from an AT in accordance with one aspect. In this embodiment, encoder 502 encodes transmission data or information bits for CDMA traffic in a manner similar to OFDMA traffic, for example, using turbo code 1/5. These coded bits are interleaved by an interleaver 504. In accordance with one aspect, the interleaver may be a reduced channel interleaver with a permutation of bits. The scrambler 506 encrypts the interleaved bits based on the MACID of the users and the pilot PN (pseudo noise) code of the sector serving the RL. It should be noted that this encryption of CDMA traffic data is different from encryption of CDMA control data. A modulator 508 modulates the encrypted CDMA traffic data by applying, for example, modulation with QPSK (quadrature phase shift keying). The resulting characters are converted into the input data of the preliminary encoder 510 with DFT (discrete Fourier transform) for further preliminary adaptation of the modulated data before transmission. The number of modulation symbols for CDMA transmission depends on the bandwidth of the CDMA segment (or the number of allocated CDMA sub-segments), as well as the number of frames interleaved. For example, a CDMA segment with 128 subcarriers on 3 physical frames corresponds to 3072 modulation symbols. Moreover, as in OFDMA traffic, repetition is used when the required number of modulation symbols corresponds to a code rate of less than 1/5.

Packet formats in CDMA traffic segments, in accordance with one aspect, support voice over IP (VoIP) communications. In one aspect, VoIP support can be optimized using two packet sizes, for example, 256 and 128, and these sizes can be used to match the frames of the full-speed and quarter-speed advanced codec with variable speed (EVRC), respectively. Packet sizes may include MAC (Media Access Control) overhead as well as cyclic redundancy check (CRC). In addition, other types of flows (not counting VoIP) can be transmitted on this segment. The conversion of CDMA streams is determined by AT using a distributed AT-oriented MAC CDMA, or other conversion. Typically, the distribution indicates which streams are allowed only on the CDMA traffic segment, only on the OFDMA traffic segment, or both. However, the AT may determine this type of information based on a data type, for example, a stream ID, or other approaches. In one aspect, the packet format used for transmitting CDMA data may be indicated by encrypting an auxiliary pilot channel RL (R-AuxPich), which carries an auxiliary pilot signal for use in data demodulation. This allows the AT to signal changes in speed for CDMA reverse transmission with minimal loss.

FIG. 6 illustrates a flow chart 600 that illustrates one aspect that can be applied to reduce the need for an RRI channel, as well as the need for demodulation / decoding of a variety of assumptions. At 602, it is determined whether the transmitted data is CDMA traffic data. If so, then the process proceeds to step 604, otherwise it reaches the final step. At 604, the auxiliary check symbols are encrypted based on the format of the packet to be transmitted, as well as the retransmission index, retransmission number in the current transmission. The retransmission number may be the ARQ transmission number that the current packet or packets represent. As set forth above and as further illustrated in FIG. 6B below, auxiliary pilot signals are transmitted in frames carrying data transmissions. Therefore, at 606, encrypted characters are included in frames carrying data. Thus, the control and data symbols in each frame undergo the same processing before transmission and are transmitted at 608. After receiving these data frames, the AP can match the encryption with different assumptions to determine the packet format and the transmission index before the data demodulation. Moreover, for subsequent transmissions on the CDMA channel, the AP can be combined with the R-AuxPich (pilot channel) from the previous transmission to identify one or more packet formats or transmission indices.

In accordance with some aspects, a data rate control channel (DRC) is transmitted carrying information regarding a data rate to be received in the forward direction. On the other hand, a reverse rate indicator (RRI) channel carrying information about a traffic channel to be transmitted in the reverse direction is also transmitted to support high speed data transfer in the forward and reverse directions in CDMA systems. The base station and the mobile station respectively exchange control information, thereby freely transmitting data. However, R-AuxPich (pilot channel) encryption based on the packet format and retransmission index eliminates the need for a potentially expensive RRI channel and the need for demodulation / decoding of many assumptions in the AP.

FIG. 7 is a flowchart that relates to another aspect, which is a power control loop for various reverse link channels in a communication system. An R-PICH is a channel that is expanded with a CDMA code of all zeros and transmitted immediately before it as an access preamble by a mobile station that transmits an initial access message on an R-CCCH (reverse common control channel). The power control loop for the R-PICH (reverse link pilot channel) and control channels is identical to the case when there is no CDMA data. The F-PCCH, the forward link power control channel, is transmitted even when CDMA data is present. Thus, the F-PCCH is transmitted under different conditions, for example, in the presence or absence of CDMA data, even if it is low cost, since it provides a stable set value of the received SNR for the pilot signal.

In the communication system, various indicators are used as indicators of the level of performance. The SNR or signal-to-noise ratio of a received signal is one such measure. This can be used to determine the transmit power level of an AT. Accordingly, at block 710, a performance indicator is measured. At 720, the measured performance metric is compared with a predetermined setpoint SNR to determine communication quality. If the measured performance indicator is less than a predetermined value, then at step 730, it can be concluded that the associated AT transmits signals with a power level that is above the optimal level. Accordingly, the AP transmits the F-PCCH in step 740 to help reduce the transmit power of the AT. This is accomplished by indicating the MACID of the AT associated with the received signal in F-PCCH transmissions. On the other hand, if it is determined at step 720 that the measured performance indicator is greater than a predetermined value, then at step 750 it is concluded that the associated AT transmits at a power level that is less than the optimum necessary. Accordingly, in step 760, the AP increases the transmit power level of the AT by transmitting an F-PCCH that contains the MACID of this AT. The system continues to monitor the transmit power level of the AT at block 710. Thus, the F-PCCH carries up-down commands that control the level at which the R-PICH is transmitted. This cycle maintains the set value of the received SNR for the pilot. These power control signals are transmitted even when CDMA data is present, thereby ensuring that the power control cycle for the R-PICH and control channels remains unaffected by the power control of the CDMA data. The power control bits for the R-PICH and control channels are a small overhead of signaling information, but they help maintain the SNRs of these channels, which would otherwise unnecessarily fluctuate if they were ACK / NACK-based power control for CDMA data. The SNR setpoint can also be used as a reference for adjusting control channel power and data. ACK / NACK-based power control is used to control the level at which CDMA data is transmitted with respect to the R-PICH.

FIG. 8 relates to a method 800 for tuning power of various control channels in a communication system based on ACK / NACK feedback. The transmit power used is initially based on the power of the last successful access attempt, and is then dynamically adjusted based on feedback received on the F-PCCH. As discussed, the aforementioned R-AuxPich is transmitted when CDMA data is present, and an AT may be skipped for transmitting OFDM data. R-AuxPich can be used as a channel estimation pilot for CDMA transmissions in the AP. R-PICH (Reverse Link Broadband Pilot Channel) provides a standard for power control over the entire bandwidth. In one aspect, the ratio of CDMA traffic power to R-AuxPich is fixed based on the packet format. For example, relationships for each packet format are established during a session configuration. The ratio of R-AuxPich to R-PICH may vary based on ACK / NACK feedback. An ACK is usually sent in response to a received transmission to indicate that the transmission has been properly received. A NACK in response to a transmission indicates that the transmission was not properly received. In response to the ACK, the transmitter transmits the following data, while in response to the NACK, the transmitter retransmits a transmission that was not properly received.

Turning now to FIG. 8, at 802, QoS flows carried in packets are determined. The QoS of packets may vary, for example, depending on the type of data carried by the packets. The final goal for adjusting the power ratio of R-AuxPich to R-PICH is then determined at step 804. At step 806, the sizes of the increase and decrease steps are determined. The final goal, as well as the step sizes of the increase and decrease, are determined for each packet based on the QoS flows carried in this packet. At 808, feedback from packet transmission is received. At block 810, the feedback is compared with the final goal to determine if the packet has ended after the goal. If so, then at step 812, the R-AuxPich / R-PICH ratio is increased by the size of the increment step, thereby increasing the transmit power of the R-AuxPich and therefore the data. If the determination in step 810 is negative, then it is concluded that the packet has completed before or in its final destination. Therefore, in step 814, the R-AuxPich / R-PICH ratio is reduced by the size of the reduction step.

FIG. 9 is a flowchart that relates to another aspect related to the load of a CDMA segment. Typically, this is controlled through segment access control and / or AP, which can also advantageously support QoS traffic, like VoIP. FIG. 9 illustrates a method 900 that employs a single bit reverse link activity (RAB) discharge as an emergency load control mechanism. The RAB bit indicates whether the load (indicated by thermal noise excess (RoT) or some other measurement) exceeds a predetermined threshold value in a particular sector. It can be used to determine which streams are allowed to transmit data over a CDMA traffic segment in each physical frame. Accordingly, the value for RAB is set initially during packet configuration. Therefore, at step 902, it is initially determined whether the configurable packets belong to QoS flows, like VoIP. If so, then at 904 they are configured to ignore the RAB bits that are being broadcast, and instead rely on admission control. If the configuration in step 902 is not associated with the QoS flow, the method proceeds to step 906, where RAB bits are obtained from each sector in the active set of the associated AT. At step 908, the received RAB bits are compared with a threshold value to determine if any of the bits that are set deviate from the threshold value. If none of the bits deviate from the threshold value, the process proceeds to step 910, where the CDMA segment is loaded. However, if any RAB bits deviate from the threshold at 912, then non-QoS traffic is instructed to stop using the CDMA segment. For further use of the RAB, the terminal listens to the RAB from each sector in its active set, observing the threshold value for RL quality (relative to the sector serving RL), if any of their received RAB bits that deviate from the threshold value are set, the terminal operates as if they were installed via RLSS. RAB is an amplitude-manipulated channel. In one aspect, an on-state RAB uses only one of the 16 codewords used by the F-PQICH (pilot quality channel transmitted from AP to AT indicating RL pilot quality from AT).

Acknowledge bits can use the same modulation as the modulation for OFDMA data to simplify RL processing on the AT. In one aspect, each user admitted to the CDMA segment is assigned an ACKID corresponding to each interlace from which it is allowed to start a packet. This ACKID is applicable in a frame in which the ACK would be transmitted for that interleaving, based on the decoding timeline specified in the concept. As discussed above, in one aspect, up to two packet start interlaces are assigned, and hence up to two ACKIDs per user, for example, during an initial session configuration. In one aspect, a CDMA ACKID of 0 corresponds to a first ACK channel not assigned to OFDMA traffic. In another aspect, where the number of ACKs assigned to OFDMA traffic depends on the bandwidth available to ACK traffic, the ACKs assigned to the CDMA data are automatically reduced based on the bandwidth allocated to the CDMA segment.

As used herein, a segment or subsegment may be a predetermined time-frequency or frequency distribution, which may be continuous or fragmented in time and / or frequency. Typically, a segment or subsegment is a subset of the available distribution, with the remainder of the distribution being used by OFDM data and control segments.

The data transmission techniques described herein may be implemented by various means. For example, these techniques may be implemented in hardware, firmware, software, or a combination thereof. For hardware implementation, the processing modules used to transmit data at the transmitter or receive data at the receiver can be implemented in one or more specialized integrated circuits (ASIC), digital signal processors (DSP), digital signal processing devices (DSPD), programmable logic devices ( PLD), Field Programmable Gate Arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, electronic devices, and other electronic modules designed to perform the functions described here, or in combinations thereof.

For firmware and / or software implementation, techniques can be implemented using modules (eg, procedures, functions, and so on) that perform the functions described here. Firmware and / or software codes may be stored in a memory device and executed by a processor. The storage device may be implemented within the processor or outside the processor.

The foregoing description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the disclosure of the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, this disclosure is not intended to be limited to the embodiments shown in this document, but should correspond to the broadest scope consistent with the principles and new features disclosed in this document.

What is described above includes examples of various embodiments. Of course, it is not possible to describe every possible combination of components or methodologies in order to describe embodiments, however, one of ordinary skill in the art may recognize that many additional combinations and permutations are permissible. Accordingly, this detailed description is intended to cover all such changes, modifications and variations that fall within the spirit and scope of the appended claims.

In particular, regarding the various functions performed by the above-described components, devices, circuits, systems, etc., the terms (including a reference to "means") used to describe such components are intended to correspond, unless otherwise indicated, to any component, which performs the specified function of the described component (for example, the functional equivalent), even if it is structurally not equivalent to the disclosed structure, which performs the function in the typical features of the variants illustrated in this document suschestvleniya. It will also be apparent that the embodiments include a system as well as a computer-readable medium having computer-executable instructions for performing actions and / or events from various methods.

Moreover, although a particular feature may be disclosed with respect to only one of several implementations, such a feature may be combined with one or more other features from other implementations, as may be necessary and beneficial for any given or specific application. In addition, if the terms “includes” and “including” and their variants are used either in the detailed description or in the claims, these terms should be encompassing, similarly to the term “comprising”.

Claims (45)

1. A method for transmitting data in a wireless communication system, comprising the steps of:
transmitting data from the access terminal through at least one data segment of a code division multiple access (CDMA) system, the data being scrambled according to a first scrambling sequence; and
transmitting control information from the access terminal through at least one CDMA control segment, wherein the control information is scrambled according to a second scrambling sequence that is different from the first scrambling sequence. 2. The method of claim 1, wherein the first scrambling sequence comprises a data medium access control identifier (MACID) of the access terminal and a pilot pseudo noise (PilotPN) of the reverse link (RL) serving sector for the access terminal. 3. The method according to claim 1, wherein the data transmission further comprises transmitting an auxiliary pilot signal through an auxiliary pilot channel (R-AuxPich). 4. The method according to claim 3, in which the data transmission is that the data is transmitted through at least one data segment when the power level is shifted from the transmit power level of the auxiliary pilot signal based on the ratio determined by the data packet format. 5. The method according to claim 3, in which the ratio of R-AuxPich to the pilot channel of the reverse link (R-PICH) is based on the final goal, the size of the step up and the size of the step down. 6. The method according to claim 5, in which the final goal, step size increase and step size decrease is determined for each package and set by the quality of service (QoS), which is contained in the corresponding package. 7. The method according to claim 1, in which at least one segment of CDMA data corresponds to at least some of the 128 subcarriers in the passband of an orthogonal frequency division multiple access (OFDMA) system. 8. The method of claim 1, further comprising transmitting an acknowledgment from the access terminal, including an acknowledgment identifier (ID) identifying the acknowledgment. 9. The method of claim 8, in which the confirmation ID corresponds to each interleaving with which the access terminal is allowed to start transmitting data in the packet. 10. The method of claim 8, further comprising selecting an acknowledgment ID from one of two acknowledgment IDs assigned to the access terminal. 11. The method of claim 8, in which at least one segment of CDMA data corresponds to at least some of the 128 subcarriers in the OFDMA bandwidth. 12. A device for transmitting data in a wireless communication system, comprising:
means for transmitting data through at least one CDMA data segment, the data being scrambled according to the first scrambling sequence;
means for transmitting control information through at least one CDMA control segment, the bandwidth of which is different from at least one CDMA data segment, wherein the control information is scrambled according to a second scrambling sequence that is different from the first scrambling sequence. 13. The device according to item 12, in which the first scrambling sequence contains
The MACID of the access terminal and the PilotPN of the sector serving the RL for the access terminal. 14. The device according to item 12, in which the means for transmitting data further comprises means for transmitting an auxiliary pilot signal through the auxiliary pilot channel. 15. The device according to 14, in which the means for transmitting data comprises means for transmitting data through at least one data segment while shifting the power level from the transmit power level of the auxiliary pilot signal based on the ratio determined by the format of the data packet. 16. The device according to clause 15, in which the ratio is based on the ultimate goal, the size of the step up and the size of the step down. 17. The device according to clause 16, in which the final goal, step size increase and step size decrease are set according to the QoS class supported by the access terminal. 18. The device according to item 12, in which at least one segment of CDMA data corresponds to at least some of the 128 subcarriers in the OFDMA bandwidth. 19. The device according to p. 12, comprising means for transmitting an acknowledgment from an access terminal including an acknowledgment ID identifying the acknowledgment. 20. The device according to claim 19, in which the confirmation ID corresponds to each interleaving, from which the access terminal is allowed to start transmitting data in a packet. 21. The device according to claim 19, further comprising means for selecting a confirmation ID from one of two confirmation IDs assigned to the access terminal. 22. The device according to claim 19, in which at least one segment of CDMA data corresponds to at least some of the 128 subcarriers in the OFDMA bandwidth. 23. A computer-readable medium in which a computer program product is stored, which, when executed by a processor of an access terminal of a wireless communication system, causes the access terminal to transmit data, the software product comprising:
commands for transmitting from the access terminal data through at least one CDMA data segment, the data being scrambled according to the first scrambling sequence;
commands for transmitting control information from the access terminal through at least one CDMA control segment, wherein the control information is scrambled according to a second scrambling sequence that is different from the first scrambling sequence. 24. The computer-readable medium of claim 23, wherein the at least one CDMA data segment corresponds to at least some of the 128 subcarriers in the OFDMA bandwidth. 25. The computer-readable medium of claim 23, further comprising instructions for expanding a given transmission with a hybrid automatic repeat request (H-ARQ) of CDMA data by the number of frames that are available from three frames that form a transmission time interval (TTI). 26. The computer-readable medium of claim 23, further comprising instructions for transmitting an acknowledgment from an access terminal including an acknowledgment ID identifying an acknowledgment. 27. The computer-readable medium of claim 26, wherein the at least one segment of CDMA data corresponds to at least some of the 128 subcarriers in the OFDMA bandwidth. 28. The computer-readable medium of claim 26, wherein the packet format used for at least the CDMA data segment is indicated by scrambling the auxiliary pilot channel RL (R-AuxPich), which carries an auxiliary pilot signal for use in data demodulation. 29. The computer-readable medium of claim 28, wherein the scrambling of the auxiliary pilot channel RL is further based on a retransmission index. 30. The computer-readable medium of claim 26, further comprising instructions for implementing a load control mechanism by reverse link activity (RAB) bits received from each sector in an active set of an associated access terminal (AT). 31. The computer-readable medium of claim 30, wherein the non-QoS (quality of service) streams are blocked if the set RAB bits deviate from a predetermined threshold value. 32. The computer-readable medium of claim 30, wherein the QoS streams are configured to ignore RAB bits. 33. An access terminal for a wireless communication system, comprising:
a transmitter for transmitting data through at least one segment of CDMA data and control information through at least one segment of CDMA control;
a processor for scrambling data according to a first scrambling sequence and scrambling control information according to a second scrambling sequence that is different from the first scrambling sequence. 34. The access terminal according to claim 33, wherein the first scrambling sequence comprises a MACID (Access Control of Media Access Data) of the access terminal and a PilotPN of a sector serving the RL for the access terminal. 35. The access terminal according to clause 34, in which the transmitter transmits an auxiliary pilot signal through an auxiliary pilot channel. 36. The access terminal according to clause 35, in which data is transmitted through at least one data segment when the power level is shifted from the transmit power level of the auxiliary pilot signal based on the relationship determined by the data packet format. 37. The access terminal according to clause 35, in which the ratio is based on the ultimate goal, the size of the step up and the size of the step down. 38. The access terminal according to clause 37, in which the final goal, step size increase and step size decrease are set according to the QoS class supported by the access terminal. 39. The access terminal of claim 33, wherein the at least one CDMA data segment corresponds to at least some of the 128 subcarriers in the OFDMA bandwidth. 40. The access terminal according to claim 33, wherein the transmitter further transmits an acknowledgment and an acknowledgment ID identifying the acknowledgment. 41. The access terminal of claim 40, wherein the acknowledgment IDs correspond to each interleaving from which the access terminal is allowed to start transmitting data in a packet. 42. The access terminal of claim 40, wherein the processor selects an acknowledgment ID from one of two acknowledgment IDs assigned to the access terminal. 43. The access terminal according to claim 33, wherein the processor implements an emergency load control mechanism in a wireless communication system by setting reverse link activity (RAB) bits if the load on their associated sector exceeds a predetermined threshold; and the transmitter broadcasts RABs to access terminals in a given sector. 44. The access terminal of claim 43, wherein the transmitter transmits non-QoS streams to stop loading data into a CDMA data segment when reverse link activity bits are set for this sector. 45. The access terminal according to item 43, in which the RAB is a channel with amplitude manipulation, activated in such a way that the RAB in the on state uses only one of the sixteen codewords used by the F-PQICH (quality pilot channel) transmitted from the access point (AP) to an access terminal (AT).

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