RU2369021C2 - Transmission with incremental redundancy in mimo communication system - Google Patents

Abstract

FIELD: communication means.

SUBSTANCE: invention is intended for transmission with incremental redundancy (IR) in MIMO communication system. Transmitter unit processes (for example, codes, divides, alternates and modulates) data packages based on the selected speed to get multiple blocks of data symbols. Transmitter unit sends one block of symbols at a time, until receiver does not errorless restore data package, or until all the blocks are transmitted. Regardless of the time of acceptance of data symbol blocks from the transmitter unit, receiver detects accepted block of data symbols to get the detected block of symbols, processes (for example, demodulates, re-alternates, selects and decodes) all the detected blocks of symbols, received for the data package, and provides decoded package. If the decoded package contains an error, then the receiver repeats processing, while another block of symbols is being accepted for the data package. Receiver may as well perform repeated iterative detection and decoding on the accepted blocks of symbols for the data package to get a decoded package.

EFFECT: improved efficiency of data transmission.

38 cl, 16 dwg

Description

FIELD OF THE INVENTION

The present invention generally relates to the exchange of information and, more specifically, to techniques for transmitting data in a communication system with many inputs and many outputs (MIMO).

State of the art

A MIMO system employs multiple (N _T ) transmit antennas and multiple (N _R ) receive antennas for data transmission and is referred to as a (N _T , N _R ) system. A MIMO channel formed by N _T transmit and N _R receive antennas can be decomposed into N _S spatial channels, where N _s ≤min {N _T , N _R }. A MIMO system can provide increased throughput if N _S spatial channels created by multi-element transmit and receive antennas are used for data transmission.

The main problem in the MIMO system is the selection of an appropriate data rate based on channel conditions. A “rate” may indicate a particular data rate or bit rate, a specific coding scheme, a particular modulation scheme, a specific data packet size, and so on. The goal of selecting a rate is to maximize throughput over N _S spatial channels along with meeting specific quality objectives that can be measured through a particular burst error rate (e.g., 1% PER).

The MIMO channel capacity depends on the signal-to-noise-and-noise ratio (SNR) achieved by the N _S spatial channels. SNRs, in turn, depend on channel conditions. In one conventional MIMO system, a transmitter encodes, modulates, and transmits data in accordance with a rate that is selected based on a static MIMO channel model. Good performance can be achieved if the model is accurate and if the MIMO channel is relatively static (i.e. does not change over time). In another conventional MIMO system, the receiver estimates the MIMO channel, selects the appropriate speed based on the channel estimates, and sends the selected speed to the transmitter. Then the transmitter processes and transmits data in accordance with the selected speed. The performance of this system depends on the features of the MIMO channel and the accuracy of the channel estimates.

For both conventional MIMO systems described above, the transmitter typically processes and transmits each data packet at the speed selected for that data packet. The receiver decodes each data packet transmitted by the transmitter and determines whether the packet is decoded correctly or in error. The receiver may send back an acknowledgment of acknowledgment (ACK) if the packet is decoded correctly, or a negative acknowledgment of acknowledgment (NAK) if the packet is decoded in error. The transmitter may retransmit each data packet decoded by the receiver in error, completely receiving the NAK for the packet from the receiver.

The performance of both of the above MIMO systems is highly dependent on the accuracy of the speed selection. If the selected speed for the data packet is too moderate (for example, since the actual SNR is much better than the SNR estimate), then excessive system resources are spent on transmitting the data packet and the channel bandwidth is underutilized. Conversely, if the selected speed for the data packet is too intense, then the packet may be decoded by the receiver with an error, and system resources may be spent on retransmission of the data packet. The choice of speed for the MIMO system is promising because of (1) the greater complexity in channel estimation for the MIMO channel and (2) the time-dependent and independent feature of the multiple spatial channels of the MIMO channel.

Therefore, there is a need in the art for techniques for efficiently transmitting data in a MIMO system that do not require accurate speed selection to achieve good performance.

SUMMARY OF THE INVENTION

This document provides techniques for performing incremental redundancy (IR) transmission in a MIMO system. Initially, the receiver or transmitter in the MIMO system evaluates the MIMO channel and selects the appropriate rate for transmitting data on the MIMO channel. The transmitter is provided with the selected speed if the receiver makes a speed selection.

The transmitter processes (for example, encodes, splits, interleaves, and modulates) the data packet based on the selected rate and obtains multiple (N _B ) data symbol blocks for the data packet. The first block of data symbols usually contains sufficient information to enable the receiver to recover the data packet under favorable channel conditions. Each of the remaining data symbol blocks contains additional redundancy to enable the receiver to recover the data packet under less favorable channel conditions. The transmitter transmits a first block of data symbols from N _T transmit antennas to N _R receive antennas at the receiver. After that, the transmitter transmits the remaining blocks of N _B data symbol blocks, one block at a time, until the data packet is restored correctly by the receiver or all of the N _B blocks are not transmitted.

If multiple (N _P ) data symbol blocks for N _P data packets need to be transmitted simultaneously from N _T transmit antennas, then the transmitter further processes these N _P data symbol blocks, so that N _P data packets experience similar channel conditions. This allows you to use a single speed for all data packets transmitted simultaneously on the MIMO channel.

The receiver receives a received symbol block for each data symbol block transmitted by the transmitter. The receiver “detects” each received symbol block to obtain a detected symbol block, which is an estimate of the corresponding data symbol block. Then the receiver processes (for example, demodulates, interleaves, iterates, and decodes) all detected blocks of characters received for the data packet and provides a decoded packet. The receiver can send back the ACK if the decoded packet is correctly decoded, and NAK if the decoded packet is in error. If the decoded packet is in error, the receiver repeats the processing when another received block of symbols is received for another block of data symbols transmitted by the transmitter.

The receiver may also recover the data packet using an iterative detection and decoding (IDD) scheme. For the IDD scheme, whenever a new received symbol block for a data packet is obtained, detection and decoding is iteratively performed multiple (N _dd ) times on all received symbol blocks to obtain a decoded packet. The detector detects all received symbol blocks and provides detected symbol blocks. The decoder decodes all detected symbol blocks and provides a priori decoder information, which is used by the detector in the subsequent iteration. A decoded packet is generated based on the decoder output for the last iteration.

Various aspects and embodiments of the invention are described in detail below.

Brief Description of the Drawings

The features and features of the present invention will become more apparent from the following detailed description, taken in conjunction with the drawings, in which the same reference characters are defined respectively throughout the document, and where:

Figure 1 shows a block diagram of a transmitter and a receiver in a MIMO system that implements IR transmission;

Figure 2 shows a process for sending and receiving IR transmission in a MIMO system;

Figure 3 shows a timing diagram that illustrates IR transmission;

4A shows a transmit (TX) data processor in a transmitter;

Fig. 4B shows a turbo encoder inside a data processor;

5 illustrates the processing of one data packet by a data processor;

6A-D show four embodiments of a spatial transmit processor in a transmitter;

FIG. 7A and 7B show demultiplexing of one data symbol block and two data symbol blocks, respectively, for an exemplary MIMO-OFDM system (orthogonal frequency division multiplexing);

Figa shows one of the embodiments of the receiver;

Fig. 8B shows a received (RX) data processor in the receiver of Fig. 8A;

Figa shows a receiver that implements iterative detection and decoding; and

Figv shows a turbo decoder.

Detailed description

The word “exemplary” is used herein to mean “serving as an example, individual case, or illustration.” Any embodiment or project described herein as “exemplary” is not necessarily to be construed as preferred or advantageous in comparison with other embodiments or projects.

For a MIMO system with N _S spatial channels, N _P data packets can be transmitted simultaneously from N _T transmit antennas, where 1≤N _P ≤N _S. A single rate can be used for all data packets transmitted simultaneously, regardless of the value of N _P. Using a single speed can simplify processing both in the transmitter and in the receiver in the MIMO system.

1 shows a block diagram of a transmitter 110 and a receiver 150 in a MIMO system 100 that implements IR transmission. At transmitter 110, a transmit data processor 120 receives data packets from a data source 112. The transmitted data processor 120 processes (for example, formats, encodes, splits, interleaves, and modulates) each data packet in accordance with the rate selected for this packet to obtain N _B data symbol blocks for the packet, where N _B > 1 and may depend on selected speed. The selected rate for each data packet may indicate the data rate, coding scheme or code rate, modulation scheme, packet size, number of data symbol blocks, and so on for that packet, which is indicated by various controls provided by the controller 140. For transmitting IR N _B data symbol blocks for each data packet are transmitted, one block at a time, until the packet is decoded correctly by receiver 150, or all N _B data symbol blocks are transmitted.

The spatial spatial processor 130 receives blocks of data symbols and performs the necessary processing to transmit each block of data symbols from all N _T transmit antennas in one time slot (or simply “slot”). An interval is a predetermined time period for a 100 MIMO system. The spatial transmit processor 130 may perform demultiplexing, spatial processing, and so on, as described below. For each slot, the spatial spatial processor 130 processes one block of data symbols, multiplexes into pilot symbols (pilot symbols) as required, and provides N _T transmitted symbol sequences to transmitter module 132 (TMTR). Each transmitted symbol may be a data symbol or control symbol.

и дополнительно ухудшает передаваемые сигналы с помощью аддитивного белого гауссовского шума и возможного взаимного влияния от других передатчиков.The transmitter module 132 receives and brings to the desired state (for example, converts to analog, upconverts, filters, and amplifies) N _T transmitted symbol sequences to obtain N _T modulated signals. Each modulated signal is then transmitted from a respective transmit antenna (not shown in FIG. 1) and through a MIMO channel to a receiver 150. The MIMO channel distorts N _T transmitted signals with a channel characteristic

and further degrades the transmitted signals using additive white Gaussian noise and possible interference from other transmitters.

At a receiver 150, N _T transmitted signals are received by each of the N _R receive antennas (not shown in FIG. 1), and N _R received signals from N _R receive antennas are provided to the receiver module 154 (RCVR). The receiver module 154 brings to the desired state, digitizes, and preprocesses each received signal to obtain a sequence of received symbols for each interval. The receiver module 154 provides N _R received symbol sequences (for data) to the receiving spatial processor 160 and received pilot symbols (for monitoring) to the channel estimator 172. The receive spatial processor 160 processes (eg, detects and multiplexes) N _R received symbol sequences for each slot to obtain a detected symbol block, which is an estimate of the data symbol block sent by transmitter 110 for that slot.

The received data processor 170 receives all detected symbol blocks that have been received for the data packet being restored (that is, the “current” packet), processes (for example, demodulates, interleaves, iterates, and decodes) these detected symbol blocks in accordance with the selected rate and provides a decoded packet, which is an estimate of the data packet sent by the transmitter 110. The received data processor 170 also provides a decoded packet state, which indicates error-free whether the packet is decoded or with an error.

Channel estimator 172 processes the received pilot symbols and / or received data symbols to obtain channel estimates (e.g., channel gain estimates and SNR estimates) for the MIMO channel. The speed selector 174 receives the channel estimates and selects the speed for the next data packet to be transmitted to the receiver 150. The controller 180 receives the selected speed from the speed selector 174 and the state of the packet from the transmit data processor 170 and collects feedback information for the transmitter 110. Feedback information may include the selected speed for the next packet, ACK or NAK for the current packet, and so on. Feedback information is processed by the spatial transmit processor 190 / transmit data processor 190, additionally brought into the desired state by the transmitter module 192 and transmitted through the feedback channel to the transmitter 110.

At transmitter 110, the signal (s) transmitted (e) by receiver 150 are received and brought into position by receiver module 146 and are further processed by receive spatial processor 148 / received data processor 148 to recover feedback information sent by receiver 150 The controller 140 receives the recovered feedback information, uses the selected rate to process the next data packet to be sent to the receiver 150, and uses the ACK / NAK to control the current IR transmission on the package.

Controllers 140 and 180 control operation at transmitter 110 and receiver 150, respectively. Memory modules 142 and 182 provide storage for program codes and data used by controllers 140 and 180, respectively. The memory modules 142 and 182 may be internal to the controllers 140 and 180, as shown in FIG. 1, or external to these controllers. The processing units shown in FIG. 1 are described in detail below.

FIG. 2 shows a flowchart of a process 200 for sending and receiving IR transmission in a MIMO system. At the beginning, the receiver estimates the MIMO channel based on pilot symbols and / or data symbols received from the transmitter (step 210). The receiver selects a single rate for transmitting data on the MIMO channel based on the channel estimates and sends the selected speed to the transmitter (step 212). The transmitter receives the selected rate and encodes the data packet in accordance with the selected rate to obtain an encoded packet (step 220). The transmitter then splits the encoded packet into N _B subpackets, where N _B can also be determined by the selected rate, and then processes each subpacket to obtain a corresponding block of data symbols (also at step 220). The transmitter transmits one data symbol block at a time from N _T transmit antennas until all N _B data symbol blocks are transmitted or ACK is received from the receiver for the data packet (step 222).

A receiver receives each transmitted block of data symbols through N _R receive antennas (step 230). Whenever a new block of data symbols is received, the receiver detects and decodes all the blocks of data symbols that have been received for the data packet (step 232). The receiver also checks the decoded packet to determine if the packet is correctly decoded (good) or in error (deleted) (also step 232). If the decoded packet is deleted, the receiver can send the NAK back to the transmitter, which uses this feedback to start transmitting the next block of data symbols for the data packet. Alternatively, the transmitter may send one block of data symbols at a time until it receives an ACK from the receiver, which may or may not send back the NAK. The receiver interrupts the processing for the data packet if the packet is decoded correctly or if all N _B data symbol blocks are received for the packet (step 234).

2 shows a specific embodiment for transmitting IR in a MIMO system. IR transmission can also be implemented by other methods, and this is within the scope of the invention. IR transmission can be implemented in both frequency division duplex (FDD) and time division duplex (TDD) systems. For an FDD system, the forward MIMO channel and the feedback channel use different frequency bands and probably observe different channel conditions. In this case, the receiver can estimate the forward MIMO channel and send back the selected speed, as shown in FIG. For a TDD system, the forward MIMO channel and the feedback channel share the same frequency band and probably observe similar channel conditions. In this case, the transmitter can estimate the MIMO channel based on the pilot sent by the receiver and use this channel estimate to select the rate for transmitting data to the receiver. Channel estimation and speed selection can be performed by the receiver, transmitter, or both.

3 illustrates IR transmission in a MIMO system. The receiver evaluates the MIMO channel, selects the speed r ₁ and sends the selected speed to the transmitter in the interval 0. The transmitter receives the selected speed from the receiver, processes the data packet (Pack 1) in accordance with the selected speed and transmits the first block of data symbols (Block 1) for the data packet in interval 1. The receiver receives, detects, and decodes the first block of data symbols, determines that Packet 1 is decoded in error, and sends back the NAK in interval 2. The transmitter receives the NAK and transmits the second block of data symbols (Block 2) for I Packet 1 in interval 3. The receiver receives Block 2, detects and decodes the first two blocks of data characters, determines that Packet 1 is still decoded with an error, and sends back the NAK in interval 4. The transmission of the block and the NAK response can be repeated any number of times . In the example shown in FIG. 3, the transmitter receives a NAK for a block of N _x -1 data symbols and transmits a block of N _x data symbols for Packet 1 in the interval m, where N _{x is} less than or equal to the total number of blocks for Packet 1. The receiver receives, detects and decodes all N _x blocks of data symbols received for Packet 1, determines that the packet is decoded correctly, and sends back the ACK in the interval m + 1. The receiver also evaluates the MIMO channel, selects the speed r ₂ for the next data packet and sends the selected speed to the transmitter in the interval m + 1. The transmitter receives the ACK for the N _x block of data symbols and interrupts the transmission of Packet 1. The transmitter also processes the next data packet (Packet 2) in accordance with the selected speed and transmits the first block of data symbols (Block 1) for Packet 2 in the interval m + 2. Processing at the transmitter and receiver continues in the same manner for each data packet transmitted through the MIMO channel.

For the embodiment shown in FIG. 3, there is a one slot delay for the ACK / NAK response from the receiver for each transmission unit. To improve channel utilization, multiple data packets may be interlaced. For example, data packets for one information channel may be transmitted at odd intervals, and data packets for another information channel may be transmitted at even intervals. More than two data channels may also alternate if the ACK / NAK delay is longer than one interval.

1. Transmitter

FIG. 4A shows a block diagram of an embodiment of a transmit data processor 120 at a transmitter 110. A transmit data processor 120 receives data packets, processes each packet based on its selected rate, and provides N _B data symbol blocks for the packet. Figure 5 illustrates the processing of one data packet by the processor 120 of the transmitted data.

In a data processor 120, a cyclic redundancy check (CRC) generator 412 receives a data packet, generates a CRC value for the data packet, and attaches a CRC value to the end of the data packet to form a formatted packet. The CRC value is used by the receiver to check if the packet is decoded correctly or with errors. Other error detection codes may also be used in place of CRC. Forward Error Correction (FEC) encoder 414 then encodes the formatted packet according to the coding scheme or code rate indicated by the selected rate, and provides an encoded packet or “codeword”. Coding increases the reliability of data transmission. The FEC encoder 414 may provide execution of block code, convolutional code, turbo code, some other code, or combinations thereof.

FIG. 4B shows a block diagram of a parallel-connected convolutional encoder 414a (or turbo encoder) that can be used for the FEC encoder 414 in FIG. 4A. The turbo encoder 414a includes two component convolutional encoders 452a and 452b, a code interleaver 454, and a multiplexer 456 (MUX). A code interleaver 454 interleaves information bits in a formatted packet (indicated by

as {d}) according to the code interleaving scheme. The constituent encoder 452a receives and encodes information bits with the first constituent code, and provides the first parity bits (denoted as {c _p1 }). Similarly, constituent encoder 452b receives and encodes interleaved information bits from code interleaver 454 with a second constituent code, and provides second parity bits (denoted as {c _p2 }). Component encoders 452a and 452b may provide two recursive systematic component codes with code rates R ₁ and R ₂ , respectively, where R ₁ may or may not be equal to R ₂ . Multiplexer 456 receives and multiplexes information bits and parity bits from constituent encoders 452a and 452b, and provides an encoded packet of code bits (denoted as {c}). The encoded packet includes information bits {d}, which are also called systematic bits and are denoted as {c _data }, followed by the first parity bits {c _p1 }, and then followed by second {c _p2 } parity bits.

Returning to FIG. 4A, separation module 416 receives and splits the encoded packet into N _B encoded subpackets, where N _B may depend on the selected rate and indicated by the separation adjustment from controller 140. The first encoded subpacket typically contains all systematic bits and zero or more control bits parity. This allows the receiver to recover the data packet using only the first encoded subpacket under favorable channel conditions. The remaining N _B -1 encoded subpackets contain the remaining first and second parity bits. Each of these N _B -1 encoded subpackets typically contains the first few parity bits and several second parity bits with parity bits crossing the entire data packet. For example, if N _B = 8 and the remaining first and second parity bits are given indices starting at 0, then the second coded subpacket may contain bits 0, 7, 14, ... of the remaining first and second parity bits, the third coded subpacket may contain bits 1, 8, 15, ... of the remaining first and second parity bits, and so on, and the eighth and last encoded subpacket may contain bits 6, 13, 20, ... of the remaining first and second parity bits. Improved decoding performance can be achieved by spreading the parity bit spectrum in parallel to the remaining N _B -1 encoded subpackets.

Channel interleaver 420 includes N _B block interleavers 422a-422nb that receives N _B coded subpackets from partition module 416. Each block interleaver 422 interleaves (i.e., reorders) the code bits for their subpacket in accordance with the interleaving scheme and provides an interleaved subpacket. Interleaving provides time, frequency, and / or spatial diversity for code bits. Multiplexer 424 connects to all N _B block interleavers 422a-422b and provides N _B interleaved subpackets, one subpacket at a time and if directed by adjusting IR transmission from controller 140. In particular, multiplexer 424 provides the interleaved subpacket from block interleaver 422a first, then the interleaved subpacket from the block interleaver 422b next and so on, and the interleaved subpacket from the block interleaver 422nb last. Multiplexer 424 provides the next interleaved subpacket if a NAK is received for a data packet. All N _B block interleavers 422a-422b may be cleared whenever an ACK is received.

Symbol conversion module 426 receives interleaved subpackets from channel interleaver 420 and converts the interleaved data in each subpacket to modulation symbols. Character conversion is performed in accordance with the modulation scheme indicated by the selected rate. Character conversion can be achieved by (1) grouping sets of B bits to form B-bit binary values, where B≥1, and (2) converting each B-bit binary value to a point on a signal constellation having 2 ^B points. This signal constellation corresponds to the selected modulation scheme, which can be BPSK (on-off phase shift keying), QPSK (quadrature phase shift keying), 2 ^B- PSK (phase shift keying), 2 ^B- QAM (quadrature amplitude modulation) and so on. As used herein, a “data symbol” is a modulation symbol for data and a “control symbol” is a modulation symbol for control. Symbol conversion module 426 provides a data symbol block for each encoded subpacket, as shown in FIG.

For each data packet, the transmitted data processor 120 provides N _B data symbol blocks, which together include N _SYM data symbols and may be denoted as

]. {s} = [s ₁ s ₂ ...

].

Each data symbol s _i , where i = 1 ... N _SYM , is obtained by converting B code bits as follows: s _i = map ( b _i ), where b _i = [b _{i, 1} b _{i, 2} ... b _{i, B} ].

The IR transmission techniques described herein can be implemented in a single-carrier MIMO system that uses a single carrier for data transmission, and in a multi-carrier MIMO system that uses multiple carriers for data transmission. Multiple carriers may be provided by orthogonal frequency division multiplexing (OFDM), other multi-carrier modulation techniques, or some other design. OFDM effectively partitions the overall system bandwidth into multiple (N _F ) orthogonal subbands, which are also commonly referred to as tones, bins, or frequency channels. With OFDM, each subband is associated with a respective carrier, which may be modulated with data.

The processing performed by the spatial spatial processor 130 and the transmitter module 132 at the transmitter 110 depends on whether one or a plurality of data packets are transmitted simultaneously and whether one or a plurality of carriers are used for data transmission. Some sample samples for these two modules are described below. For simplicity, the following description assumes a full-rank MIMO channel with N _s = N _T ≤N _R. In this case, one modulation symbol may be transmitted from each of the N _T transmit antennas for each subband in each symbol period.

6A shows a block diagram of a spatial spatial processor 130a and a transmitter module 132a that can be used to transmit IR one packet at a time in a single carrier MIMO system. The spatial transmit processor 130a includes a multiplexer / demultiplexer 610 (MUX / DEMUX) that receives a block of data symbols and demultiplexes the data symbols in a block into N _T subblocks for N _T transmit antennas. Multiplexer / demultiplexer 610 also multiplexes pilot symbols (e.g., by time division multiplexing (TDM)) and provides N _T transmitted symbol sequences for N _T transmit antennas. Each transmitted sequence of characters is intended to be transmitted from one transmitting antenna in one slot. Each transmitted symbol may be a data symbol or control symbol.

Transmitter module 132a includes N _T transmit RF modules 652a through 652t for N _T transmit antennas. Each transmit RF module 652 receives and brings to the desired state a corresponding transmit sequence of symbols from the spatial transmit processor 130a to form a modulated signal. N _T modulated signals from transmitting RF modules 652a through 652t are transmitted from N _T transmit antennas 672a through 672t, respectively.

6B shows a block diagram of a spatial spatial processor 130b and transmitter module 132a that can be used to transmit IR multiple packets simultaneously in a single-carrier MIMO system. Spatial processor 130b includes a matrix multiplication unit 620 that receives N _P data symbol blocks for transmission in one slot, where 1≤N _P ≤N _S. Module 620 performs data symbol matrix multiplication in N _P blocks with a transmission basis matrix and a diagonal matrix as follows:

есть вектор {N_T×1} данных;Where

there is a vector {N _T × 1} of data;

есть заранее оговоренный вектор {N_T×1} данных;

there is a predefined vector {N _T × 1} of data;

есть матрица {N_T×N_T} базиса передачи, которая является унитарной матрицей; и

there is a transmission basis matrix {N _T × N _T }, which is a unitary matrix; and

есть диагональная матрица {N_T×N_T}.

there is a diagonal matrix {N _T × N _T }.

включает в себя N_T элементов для N_T передающих антенн с N_P элементами, устанавливаемыми в N_P символов данных из N_P блоков, и остающиеся N_T-N_P элементы, устанавливаемые в ноль. Вектор

включает в себя N_T элементов для N_T заранее оговоренных символов, которые необходимо отправить от N_T передающих антенн в одном периоде символов. Матрица

базиса передачи позволяет отправить каждый блок символов данных от всех N_T передающих антенн. Это дает возможность всем N_P блокам символов данных испытывать схожие условия канала и дополнительно позволяет использоваться единой скорости для всех N_P пакетов данных. Матрица

также позволяет полной мощности P_ant каждой передающей антенны быть использованной для передачи данных. Матрица

может быть определена какVector

includes N _T elements for N _T transmit antennas with N _P elements set to N _P data symbols from N _P blocks, and the remaining N _T -N _P elements set to zero. Vector

includes N _T elements for N _T predetermined symbols to be sent from N _T transmit antennas in one symbol period. Matrix

The transmission basis allows each block of data symbols to be sent from all N _T transmit antennas. This allows all N _P blocks of data symbols to experience similar channel conditions and additionally allows the use of a single speed for all N _P data packets. Matrix

also allows the total power P _{ant of} each transmit antenna to be used for data transmission. Matrix

can be defined as

есть матрица Адамара - Уолша (Walsh-Hadamard). Матрица

также может быть определена какWhere

there is a Hadamard-Walsh matrix (Walsh-Hadamard). Matrix

can also be defined as

есть матрица дискретного преобразования Фурье (DFT) с (k,i)-ым элементом, определенным какWhere

is the discrete Fourier transform (DFT) matrix with the (k, i) -th element defined as

где m есть индекс ряда и n есть индекс столбца для матрицы

с m=1 … N_T и n=1 … N_T. Диагональная матрица

может использоваться для распределения различных мощностей передачи на N_P блоков символов данных, соответствующих общему ограничению P_tot мощности передачи для каждой передающей антенны. «Эффективная» характеристика канала, наблюдаемая приемником, тогда равна

. Эта схема передачи описывается более подробно в Патентной заявке США номер 10/367,234, озаглавленной «Rate Adaptive Transmission Scheme for MIMO Systems» (Схема передачи с адаптивной скоростью передачи для систем MIMO), зарегистрированной 14 февраля 2003 г.

where m is the index of the series and n is the column index for the matrix

with m = 1 ... N _T and n = 1 ... N _T. Diagonal matrix

can be used to distribute different transmit powers to N _P data symbol blocks corresponding to the general transmit power limit P _tot for each transmit antenna. The “effective” channel response observed by the receiver is then equal to

. This transmission scheme is described in more detail in US Patent Application No. 10 / 367,234, entitled "Rate Adaptive Transmission Scheme for MIMO Systems", registered February 14, 2003.

A multiplexer 622 receives predetermined symbols from the matrix multiplication module 620, multiplexes the pilot symbols, and provides N _T transmitted symbol sequences for N _T transmit antennas. Transmitter module 132a receives and drives N _T transmitted symbol sequences and generates N _T modulated signals.

6C shows a block diagram of a spatial spatial processor 130a and a transmitter module 132b that can be used to transmit IR one packet at a time in a MIMO-OFDM system. In the spatial transmit processor 130a, the multiplexer / demultiplexer 610 receives and demultiplexes the data symbols, multiplexes the pilot symbols, and provides N _T transmitted symbol sequences for N _T transmit antennas.

Transmitter module 132b includes N _T OFDM modulators 660a-660t, and N _T transmit RF modules 666a-666t for N _T transmit antennas. Each OFDM modulator 660 includes an inverse fast Fourier transform (IFFT) module 662 and a cyclic prefix generator 664. Each OFDM modulator 660 receives a corresponding transmitted symbol sequence from the spatial transmit processor 130a and groups each set of N _F transmitted symbols and a zero signal value for the N _F subbands. (Subbands not used for data transmission are filled with zeros). IFFT module 662 converts each set of N _F transmitted symbols and zeros to the time domain using an N _F -point inverse fast Fourier transform, and provides a corresponding transformed symbol that contains N _F symbols of a noise-like sequence. A cyclic prefix generator 664 repeats a portion of each transformed symbol to obtain a corresponding OFDM symbol that contains N _F + N _cp symbols of a noise-like sequence. The repeated part is called a cyclic prefix, and N _cp indicates the number of repeated characters of the noise-like sequence. The cyclic prefix ensures that the OFDM symbol retains its orthogonal properties in the presence of multipath delay spread caused by selective frequency attenuation (i.e., a frequency response that is uneven). The cyclic prefix generator 664 provides an OFDM symbol sequence for a transmitted symbol sequence, which is further brought to the desired state by an associated radio frequency transmitting module 666 to generate a modulated signal.

7A shows demultiplexing a data symbol block for an exemplary MIMO-OFDM system with four transmit antennas (N _T = 4) and 16 subbands (N _F = 16). A data symbol block may be denoted as {s} = [s ₁ s ₂ ... s _N ]. For the embodiment shown in FIG. 7A, demultiplexing is performed such that the first four data symbols s ₁ through s ₄ are sent in a subband 1 of transmission antennas 1 through 4, respectively, the next four data symbols s ₅ through s ₈ are sent in a subband 2 of transmission antennas 1 through 4, respectively and so on.

6D shows a block diagram of a spatial spatial processor 130c and a transmitter module 132b that can be used to transmit IR multiple packets simultaneously in a MIMO-OFDM system. The spatial processor 130c transmit multiplexer / demultiplexer 630 receives N _P data symbol blocks, where 1≤N _P ≤N _S, and provides the data symbols in each block to different subbands and different transmit antennas, as illustrated below. Multiplexer / demultiplexer 630 also multiplexes pilot symbols and provides N _T transmitted symbol sequences for N _T transmit antennas.

7B shows an embodiment of multiplexing / demultiplexing two data symbol blocks (N _p = 2) for an exemplary MIMO-OFDM system with four transmit antennas (N _T = 4) and 16 subbands (N _F = 16). For the first block of data symbols, the first four symbols s _1,1 , s _1,2 , s _1,3 and s _{1,4 of} data are transmitted on 1, 2, 3 and 4 subbands, respectively, of transmitting antennas 1, 2, 3 and 4 , respectively. The next four characters s _1,5 , s _1,6 , s _1,7 and s _1,8 data are wrapped and transmitted on the 5, 6, 7 and 8 subbands, respectively, of the transmitting antennas 1, 2, 3 and 4, respectively. For the second block of data symbols, the first four symbols s _2,1 , s _2,2 , s _2,3 and s _2,4 data are transmitted on 1, 2, 3 and 4 subbands, respectively, of the transmitting antennas 3, 4, 1 and 2 , respectively. The next four characters s _2.5 , s _2.6 , s _2.7 and s _2.8 data are wrapped and transmitted on the 5, 6, 7 and 8 subbands, respectively, of the transmitting antennas 3, 4, 1 and 2, respectively. For the embodiment shown in FIG. 7B, a plurality of N _F frequency domain values for each transmit antenna for each symbol period includes transmit symbols for some subbands and zeros for other subbands.

FIG. 7B shows the transmission of two blocks of data symbols simultaneously over N _F subbands and N _T transmit antennas. In general, any number of data symbol blocks can be transmitted simultaneously through subbands and transmit antennas. For example, one, two, three, or four blocks of data symbols may be transmitted simultaneously in FIG. However, the number of data symbol blocks that can be reliably transmitted at the same time depends on the rank of the MIMO channel, so that N _P should be less than or equal to N _S. The transmission scheme shown in FIG. 7B provides a simple transmission adaptation of a different number of data symbol blocks simultaneously based on the rank of the MIMO channel.

For the embodiment shown in FIG. 7B, each data symbol block is transmitted diagonally through NF subbands and from all N _T transmit antennas. This provides both frequency and spatial diversity for all N _P blocks of data symbols transmitted simultaneously, which allow using a single speed for all data packets. However, different rates can also be used for different data packets transmitted simultaneously. The use of different speeds may provide better performance for some receivers, such as, for example, a line receiver that does not support the execution of the IDD circuit. IR transmission of multiple data packets at different rates is simultaneously described in US Patent Application No. 10 / 785,292, entitled “Incremental Redundancy Transmission for Multiple Parallel Channels in a MIMO Communication System”, registered with MIMO February 23, 2004

Multiplexing / demultiplexing can also be performed by other methods when achieving both frequency and spatial diversity. For example, multiplexing / demultiplexing may be such that all N _F subbands of each transmit antenna are used to carry the transmitted symbols. Since the total power of each transmit antenna is limited by P _ant , the amount of transmit power available for each transmit symbol depends on the number of subbands carrying the transmit symbols.

Returning back to FIG. 6D, the transmitter module 132b receives and brings to the desired state N _T transmitted symbol sequences from the spatial transmit processor 130 c and generates N _T modulated signals.

2. Receiver

FIG. 8A shows a block diagram of a receiver 150a, which is one embodiment of a receiver 150 in FIG. 1. At the receiver 150 a, N _R receive antennas 810 a through 810 r receive N _T modulated signals transmitted by the transmitter 110 and provide N _R received signals N _{R to the} receiving RF modules 812 a through 812 r, respectively, in the receiver module 154. Each receiving RF module 812 brings to the desired state and digitizes its received signal and provides a stream of symbols / symbols of a noise-like sequence. For a single-carrier MIMO system, OFDM demodulators 814a-814r are not needed, and each receiving RF module 812 provides a symbol stream to a corresponding demultiplexer 816 directly. For the MIMO-OFDM system, each receiving RF module 812 provides a noise-like sequence symbol stream to a corresponding OFDM demodulator 814. Each OFDM demodulator 814 performs OFDM demodulation on its noise-like sequence symbol stream by (1) removing a cyclic prefix in each received OFDM symbol to obtain a received converted symbol, and (2) converting each received converted symbol to the frequency domain using a fast Fourier transform ( FFT) to obtain N _F received symbols for N _F subbands. For both systems, demultiplexers 816a through 816r receive N _R symbol streams from receiving RF modules 812 or OFDM demodulators 814, provide N _R received symbol sequences (for data) for each slot to a receive spatial processor 160a, and provide received pilot symbols to a channel estimator 172.

характеристик канала, если пространственная обработка не выполняется на передатчике. В альтернативном варианте осуществления обнаружение может выполняться на основе эффективной матрицы

оценки канала, если символы данных заранее перемножаются с матрицей

базиса передачи на передатчике для системы MIMO с единственной несущей. Для простоты последующее описание предполагает, что матрица

базиса передачи не использовалась. Модель для системы MIMO-OFDM может выражаться как:The receive spatial processor 160a includes a detector 820 and a multiplexer 822. The detector 820 performs spatial or space-time processing (or "detection") on N _R received symbol sequences to obtain N _T detected symbol sequences. Each detected symbol is an estimate of the data symbol transmitted by the transmitter. Detector 820 may implement a maximum ratio combining (MRC) detector, a linear zero-return (ZF) detector of negligible coefficients (also called a channel correlation matrix (CCMI) detector), a minimum mean square error (MMSE) detector, and an MMSE linear corrector (MMSE) -LE), decision feedback equalizer (DFE), or some other detector / corrector. Detection may be performed based on matrix estimation

channel characteristics if spatial processing is not performed at the transmitter. In an alternative embodiment, detection may be based on an effective matrix

channel estimates if the data symbols are pre-multiplied with the matrix

transmitter base for a single carrier MIMO system. For simplicity, the following description assumes that the matrix

transmission basis was not used. The model for the MIMO-OFDM system can be expressed as:

есть вектор {N_T×1} данных с N_T элементами для N_T символов данных, переданных от N_T передающих антенн по поддиапазону k;Where

there is a vector {N _T × 1} of data with N _T elements for N _T data symbols transmitted from N _T transmit antennas over subband k;

есть вектор {N_R×1} приема с N_R элементами для N_R принятых символов, полученных через N_R приемных антенн по поддиапазону k;

there is a receiving vector {N _R × 1} with N _R elements for N _R received symbols received through N _R receiving antennas over subband k;

есть матрица {N_R×N_T} характеристик канала для поддиапазона k; и

there is a matrix of {N _R × N _T } channel characteristics for subband k; and

есть вектор аддитивного белого гауссовского шума (AWGN).

is the additive white Gaussian noise (AWGN) vector.

предполагается имеющим нулевое значение, и ковариационная матрица

, где

есть дисперсия шума, и

есть единичная матрица с единичками по диагонали и нулями где-либо еще.Vector

assumed to be zero, and the covariance matrix

where

there is noise variance, and

there is an identity matrix with ones on the diagonal and zeros elsewhere.

включает в себя N_T символов данных, отправленных от N_T передающих антенн.For a MIMO-OFDM system, the receiver performs detection separately for each of the subbands used for data transmission. The following description is for one subband, and for simplicity, the index k of the range is omitted in the mathematical derivation. The following description also applies to a single carrier MIMO system. For simplicity, it is assumed that the vector

includes N _T data symbols sent from N _T transmit antennas.

Spatial processing through an MRC detector can be expressed as:

есть характеристика детектора MRC, которая равна

;Where

there is a characteristic of the MRC detector, which is equal

;

есть вектор {N_T×1} обнаруженных символов для детектора MRC; и

there is a vector {N _T × 1} of detected symbols for the MRC detector; and

“ ^H ” stands for conjugate transpose.

, где

есть i-тый столбец

, и задается как

, где

есть вектор характеристики канала между передающей антенной i и N_R приемными антеннами.The detected symbol for the transmitting antenna i can be expressed as

where

there is an i-th column

, and is set as

where

there is a channel response vector between the transmitting antenna i and N _R receiving antennas.

Spatial processing through an MMSE detector can be expressed as:

Where

для детектора MMSE. Характеристика детектора MMSE для передающей антенны i может выражаться как

for MMSE detector. The MMSE detector characteristic for transmit antenna i can be expressed as

Spatial processing by means of a zero vanishing detector can be expressed as:

Where

для детектора обращения в нуль незначащих коэффициентов. Характеристика детектора обращения в нуль незначащих коэффициентов для передающей антенны i может выражаться как

for a zero vanishing detector. The characteristic of the zero vanishing detector for transmitting antenna i can be expressed as

. Мультиплексор 822 принимает N_T обнаруженных последовательностей символов от детектора 820 и выполняет обработку дополнительно к выполненной пространственным процессором 130 передачи на передатчике. Если только один блок символов данных передается в каждом интервале, как для пространственного процессора 130а передачи на фиг. 6А и 6С, то мультиплексор 822 мультиплексирует обнаруженные символы в N_T последовательностях в один обнаруженный блок символов. Если многочисленные блоки символов данных передаются в каждом интервале, как для пространственных процессоров 130а и 130с передачи на фиг. 6В и 6D соответственно, то мультиплексор 822 мультиплексирует и демультиплексирует обнаруженные символы в N_T последовательностях в N_P обнаруженных блоков символов (не показаны на фиг.8А). В любом случае, каждый обнаруженный блок символов является оценкой блока символов данных, переданного передатчиком.For each interval, detector 820 provides N _T detected symbol sequences that correspond to N _T elements

. A multiplexer 822 receives N _T detected symbol sequences from the detector 820 and performs processing in addition to the transmission performed by the spatial processor 130 at the transmitter. If only one block of data symbols is transmitted in each slot, as for the spatial transmit processor 130a in FIG. 6A and 6C, the multiplexer 822 multiplexes the detected symbols in N _T sequences into one detected symbol block. If multiple blocks of data symbols are transmitted in each slot, as for the spatial transmit processors 130a and 130c in FIG. 6B and 6D, respectively, the multiplexer 822 multiplexes and demultiplexes the detected symbols in N _T sequences in N _P detected symbol blocks (not shown in FIG. 8A). In any case, each detected symbol block is an estimate of the data symbol block transmitted by the transmitter.

характеристик канала для канала MIMO и минимальный уровень шума в приемнике (например, на основе принятых контрольных символов) и предоставляет оценки канала контроллеру 180. В контроллере 180 модуль 176 вычисления матриц выводит характеристику

детектора (которая может быть

или

на основе оцененной матрицы характеристик канала, как описано выше, и предоставляет характеристику детектора детектору 820. Детектор 820 предварительно перемножает вектор

Channel estimator 172 estimates the matrix

channel characteristics for the MIMO channel and the minimum noise level at the receiver (for example, based on the received pilot symbols) and provides channel estimates to the controller 180. In the controller 180, the matrix calculation module 176 outputs the characteristic

detector (which may be

or

based on the estimated channel response matrix, as described above, and provides the detector response to the detector 820. The detector 820 pre-multiplies the vector

детектора, чтобы получить вектор

обнаруженных символов. Селектор 174 скорости (который реализуется контроллером 180 для варианта осуществления приемника, показанного на фиг.8А) выполняет выбор скорости на основе оценок канала, как описано ниже. Таблица 184 поиска (LUT) хранит множество скоростей, поддерживаемых системой MIMO, и множество значений параметра, ассоциативно связанных с каждой скоростью (например, скорость передачи данных, размер пакета, схема кодирования или скорость кода, схема модуляции и так далее для каждой скорости). Селектор 174 скорости обращается к LUT 184 за информацией, используемой для выбора скорости.received characters with characteristic

detector to get a vector

detected characters. A speed selector 174 (which is implemented by the controller 180 for the receiver embodiment shown in FIG. 8A) performs speed selection based on channel estimates, as described below. A search table (LUT) 184 stores a plurality of rates supported by the MIMO system and a plurality of parameter values associated with each rate (e.g., data rate, packet size, coding scheme or code rate, modulation scheme, etc. for each rate). The speed selector 174 accesses the LUT 184 for information used to select the speed.

FIG. 8B shows a block diagram of a received data processor 170a, which is one embodiment of a received data processor 170 in FIGS. 1 and 8A. In the received data processor 170a, the symbol recovery module 830 receives the detected symbol blocks from the spatial reception processor 160a, one block at a time. For each detected symbol block, the symbol recovery module 830 demodulates the detected symbols in accordance with the modulation scheme used for that block (as indicated by the demodulation adjustment from the controller 180), and provides a demodulated data block to the channel deinterleaver 840. Reversed channel interleaver 840 includes a demultiplexer 842 and N _B block inverse interleavers 844a-844nb. Prior to receiving a new data packet, block deinterleavers 844a through 844nb are initialized with erasures. An erasure is a value that replaces with a missing bit of code (that is, one that has not yet been accepted), and that sets the corresponding weight in the decoding process. A multiplexer 842 receives demodulated data blocks from a symbol recovery module 830 and provides each demodulated data block to a proper inverse block interleaver 844. Each inverted block interleaver 844 interleaves demodulated data back in their block in a manner complementary to the interleaving performed on the transmitter for that block. If the interleaving is dependent on the selected speed, then the controller 180 provides a reverse interleave adjustment to block the inverted interleavers 844, as indicated by the dashed line.

Whenever a new block of data symbols is received from the transmitter for a data packet, decoding is performed again on all blocks received for that packet. The reassembly module 848 forms a packet of deinterleaved data for subsequent decoding. A deinterleaved data packet contains (1) deinterleaved data blocks for all data symbol blocks received for the current packet, and (2) deletion for data symbol blocks not received for the current packet. The reassembly module 848 performs reassembly by a method complementary to the separation performed by the transmitter, as indicated by the reassembly adjustment from the controller 180.

Enhanced Error Code Correction (EEC) decoder 850 decodes the de-interleaved data packet in a manner complementary to FEC (forward error correction) encoding performed on the transmitter, as indicated by the decoding adjustment from controller 180. For example, a turbo decoder or a Viterbi decoder can be used to an 850 FEC decoder if turbo or convolutional coding is respectively performed on the transmitter. The 850 FEC decoder provides a decoded packet for the current packet. The CRC verification device 852 checks the decoded packet to determine if the packet is correctly decoded or in error, and provides the status of the decoded packet.

FIG. 9A shows a block diagram of a receiver 150b, which is another embodiment of a receiver 150 in FIG. The receiver 150b implements an iterative detection and decoding (IDD) scheme. For simplicity, the IDD scheme is described below for the coding scheme shown in FIGS. 4B and 5, which encodes a data packet into three parts — systematic bits {c _data }, first bits {c _p1 } of parity and second bits {c _p2 } of control parity.

Receiver 150b includes a detector 920 and an FEC decoder 950, which iteratively detect and decode the received symbols for the data packet to obtain a decoded packet. The IDD scheme takes advantage of channel code error correction capabilities to provide improved performance. This is achieved by iteratively passing a priori information between detector 920 and FEC decoder 950 during N _dd iterations,

where N _dd > 1, as described below. A priori information indicates the likelihood of the transmitted bits.

Receiver 150b includes a spatial receive processor 160b and a received data processor 170b. Inside the receive spatial processor 160b, a buffer 918 receives and stores N _R received symbol sequences provided by the receiver module 154 for each slot. Whenever a new block of data symbols is received from the transmitter for a data packet, iterative detection and decoding is performed anew (that is, from the beginning) on all received symbols for all blocks received for that packet. Detector 920 performs spatial processing or detection on the N _R received symbol sequences for each received block and provides N _T detected symbol sequences for this block. Detector 920 may implement an MRC detector, a null factor detector, an MMSE detector, or some other detector / corrector. For simplicity, detection with an MMSE detector is described below.

для передающей антенны i может выражаться:For MMSE detector with iterative detection and decoding, the detected symbol

for transmitting antenna i can be expressed:

и

выводятся на основе критерия MMSE, который может выражаться как:Where

and

are derived based on the MMSE criterion, which can be expressed as:

Solutions to the optimization problem posed in equality (7) can be expressed as:

and

from

and

есть i-ый столбец матрицы

характеристик канала;Where

there is the i-th column of the matrix

channel characteristics;

равен

с установленным в нуль i-ым столбцом;

is equal to

with the i-th column set to zero;

есть вектор {(N_T-1)×1}, полученный посредством удаления i-ого элемента

;

there is a vector {(N _T -1) × 1} obtained by removing the ith element

;

есть ожидаемые значения элементов вектора

; и

there are expected values of vector elements

; and

есть ковариационная матрица вектора

.

is the covariance matrix of the vector

.

является векторным проигрышем энергии вектора

характеристик канала для передающей антенны i.Matrix

is a vector loss of vector energy

channel characteristics for transmitting antenna i.

является ковариационной матрицей взаимного влияния на передающую антенну i. Вектор

является ожидаемым значением взаимного влияния на передающую антенну i.Matrix

is the covariance matrix of the mutual influence on the transmitting antenna i. Vector

is the expected value of the mutual influence on the transmitting antenna i.

Equality (6) can be simplified as:

и

есть выборка гауссова шума с нулевым значением и дисперсией

Where

and

there is a sample of Gaussian noise with zero value and dispersion

предполагает, что взаимное влияние от других передающих антенн является гауссовым после детектора MMSE.Gaussian noise sample

suggests that the interference from other transmitting antennas is Gaussian after the MMSE detector.

In the following description, the superscript n denotes the nth detection / decoding iteration, and the subscript m denotes the mth data symbol block received for the current packet being restored. For the first iteration (i.e., n = 1), the detection is based solely on the received symbols, since there is no a priori information available from the FEC decoder. From here, bits are allowed that are equally likely to be '1' or '0'. In this case, equality (8) is reduced to a linear MMSE detector, which can be set as

. Для каждой последующей итерации (то есть n>1), априорная информация, предоставляемая декодером FEC, используется детектором. Так как количество итераций увеличивается, взаимное влияние уменьшается и детектор стремится к детектору MRC, который достигает полного разнесения.

. For each subsequent iteration (i.e., n> 1), the prior information provided by the FEC decoder is used by the detector. As the number of iterations increases, the mutual influence decreases and the detector tends to the MRC detector, which reaches full diversity.

.For each block of data symbols received for the current packet, the detector 920 in FIG. 9A detects on N _R received symbol sequences for that block and provides N _T detected symbol sequences. A multiplexer 922 multiplexes the detected symbols in N _T sequences to obtain a detected symbol block that is provided to the received data processor 170b. The detected symbol block obtained at the nth detection / decoding iteration for the mth data symbol block is denoted as

.

является оценкой символа

данных, которая получается посредством преобразования B битов кода b _i=[b_i,1 b_i,2 … b_i,B] в точку на сигнальном созвездии. LLR для j-ого бита обнаруженного символа

может выражаться как:In the received data processor 170b, the logarithmic likelihood ratio (LLR) module 930 receives the detected symbols from the spatial reception processor 160b and calculates LLR B code bits for each detected symbol. Each character found

is a character rating

data, which is obtained by converting B bits of code b _i = [b _{i, 1} b _{i, 2} ... b _{i, B} ] to a point on the signal constellation. LLR for the jth bit of a detected symbol

may be expressed as:

есть j-ый бит для обнаруженного символа

;Where

there is a j-th bit for the detected character

;

есть вероятность обнаруженного символа

с битом

являться 1;

there is a probability of a detected character

with a bit

be 1;

есть вероятность обнаруженного символа

с битом

являться -1 (то есть '0');

there is a probability of a detected character

with a bit

be -1 (i.e. '0');

есть LLR бита

.and

have LLR bits

.

} представляют априорную информацию, предоставленную детектором декодеру FEC, и называется так же, как и LLR детектора.LLR {

} represent the a priori information provided by the detector to the FEC decoder, and is called the same as the LLR of the detector.

являлись независимыми. Равенство (14) тогда может выражаться как:For simplicity, the interleaving is assumed such that B bits for each detected symbol

were independent. Equality (14) can then be expressed as:

есть множество точек в сигнальном созвездии, чей j-тый бит равен q,Where

there are many points in the signal constellation whose jth bit is q,

(то есть «гипотетический» символ);s is a modulation symbol or an estimated point in the set

(that is, a “hypothetical” symbol);

есть коэффициент усиления для передающей антенны i и определяется выше;

there is a gain for the transmitting antenna i and is determined above;

есть дисперсия выборки гауссова шума

для обнаруженного символа

;

there is a variance of the sample of Gaussian noise

for a detected character

;

есть множество B битов для гипотетического символа s;

there are many B bits for the hypothetical character s;

равен

с удаленным j-ым битом;

is equal to

with the jth bit removed;

есть множество LLR, полученных от декодера FEC для B битов гипотетического символа s;

there are many LLRs received from the FEC decoder for B bits of the hypothetical symbol s;

равен

с декодером LLR для удаленного j-ого бита (то есть,

); и

is equal to

with an LLR decoder for the remote jth bit (i.e.,

); and

“ ^T ” stands for transposition.

The LLR decoder for the (i, j) -th bit can be expressed as:

есть вероятность бита

являться 1; иWhere

there is a chance of a bit

be 1; and

есть вероятность бита

являться -1.

there is a chance of a bit

be -1.

(j) устанавливаются в нули, чтобы обозначать равную вероятность каждого бита быть 1 или -1, так как нет априорной информации, доступной для бита. Для каждой последующей итерации элементы

(j) вычисляются на основе «гибких» значений для битов из декодера FEC. Модуль 930 вычисления LLR предоставляет LLR для битов кода каждого обнаруженного символа, принятого от пространственного процессора 160b приема. Блок LLR, полученный на n-ой итерации обнаружения/декодирования для m-ого блока символов данных, обозначается как

.For the first iteration (n = l), all elements

(j) are set to zeros to indicate the equal probability of each bit being 1 or -1, since there is no a priori information available for the bit. For each subsequent iteration, the elements

(j) are computed based on “flexible” values for the bits from the FEC decoder. LLR calculation module 930 provides an LLR for the code bits of each detected symbol received from the receive spatial processor 160b. The LLR block obtained at the nth detection / decoding iteration for the mth data symbol block is denoted as

.

. Декодер 950 FEC принимает и декодирует пакет LLR от модуля 948 повторной сборки, как описано ниже.The reverse channel interleaver 940 receives and interleaves each LLR block from the LLR calculation unit 930, and provides back-interleaved LLRs for the block. The reassembly module 948 generates an LLR packet that contains (1) blocks of deinterleaved LLRs from channel deinterleaver 940 for all data symbol blocks received from the transmitter, and (2) zero LLR blocks for unreceived data symbol blocks. The LLR packet for the nth detection / decoding iteration is denoted as

. The FEC decoder 950 receives and decodes the LLR packet from the reassembly module 948, as described below.

FIG. 9B shows a block diagram of a turbo decoder 950a that can be applied to FEC decoders 950 and 850 in FIGS. 9A and 8B, respectively. Turbo decoder 950a performs iterative decoding for a parallel-related convolutional code, such as that shown in FIG. 4B.

LLR от модуля 948 повторной сборки (который также обозначается как входные LLR) на информационный бит

LLR, первый бит

контроля четности LLR и второй бит

контроля четности LLR. Декодер 954а с гибким входом/гибким выходом (SISO) принимает информационный бит

LLR и первый бит

контроля четности LLR от демультиплексора 952, и обратно перемеженный информационный бит

LLR от обращенного перемежителя 958 кода. Декодер 954а SISO затем извлекает новые LLR для данных и первых битов

и

контроля четности на основе первого составляющего сверточного кода. Перемежитель 956 кода перемежает информационный бит

LLR в соответствии со схемой кодового перемежения, используемой на передатчике, и предоставляет перемеженный информационный бит

LLR. Подобным образом декодер 954b SISO принимает информационный бит

LLR и второй бит

контроля четности от демультиплексора 952, и перемеженный информационный бит

LLR от кодового перемежителя 956. Декодер 954b SISO затем извлекает новые LLR для данных и вторых битов

и

контроля четности на основе второго составляющего сверточного кода. Обращенный перемежитель 958 кода обратно перемежает информационный бит

LLR дополнительным способом по отношению к кодовому перемежению и предоставляет обратно перемеженный информационный бит

LLR. Декодеры 954а и 954b SISO могут реализовывать максимально апостериорный (МАР) алгоритм BCJR SISO либо его производные меньшей сложности, алгоритм гибкого выхода Витерби (Viterbi) или какой-либо другой алгоритм декодирования, которые известны в данной области техники.In turbo decoder 950a, demultiplexer 952 receives and demultiplexes a packet

LLR from reassembly module 948 (which is also referred to as input LLRs) per information bit

LLR, first bit

LLR parity and second bit

parity LLR. Flexible Input / Flexible Output (SISO) Decoder 954a receives information bit

LLR and first bit

LLR parity from demultiplexer 952, and back-interleaved information bit

LLR from code deinterleaver 958. SISO decoder 954a then extracts new LLRs for data and first bits

and

parity based on the first component convolutional code. Code interleaver 956 interleaves the information bit

LLR in accordance with the code interleaving scheme used at the transmitter and provides an interleaved information bit

LLR. Similarly, the SISO decoder 954b receives the information bit

LLR and second bit

parity from demultiplexer 952, and interleaved information bit

LLR from code interleaver 956. SISO decoder 954b then extracts new LLRs for data and second bits

and

parity based on the second component convolutional code. Reverse code interleaver 958 interleaves the information bit

LLR in an additional way with respect to code interleaving and provides a reverse interleaved information bit

LLR. SISO decoders 954a and 954b can implement the maximum posterior (MAP) BCJR SISO algorithm or its derivatives of less complexity, the Viterbi flexible output algorithm, or some other decoding algorithm that is known in the art.

LLR и итоговый первый бит

контроля четности от декодера 954а SISO, обратно перемеженный итоговый информационный бит

LLR от обращенного перемежителя 958 кода и итоговый второй бит

контроля четности LLR от декодера 954b SISO. Сумматор/мультиплексор 960 затем вычисляет LLR

декодера для следующей итерации n+1 обнаружения/декодирования следующим образом:

. LLR

декодера соответствуют

в равенстве (16) и представляют априорную информацию, предоставляемую детектору декодером FEC.Decoding by SISO decoders 954a and 954b is repeated N _dec times for the current iteration n of detection / decoding, where N _dec ≥ 1. After all N _dec decoding iterations are completed, adder / multiplexer 960 receives the final information bit

LLR and final first bit

parity from SISO decoder 954a, reverse interleaved total information bit

LLR from code deinterleaver 958 and the resulting second bit

LLR Parity from SISO Decoder 954b. The adder / multiplexer 960 then calculates the LLR

decoder for the next iteration n + 1 detection / decoding as follows:

. LLR

decoder match

in equality (16) and represent the a priori information provided to the detector by the FEC decoder.

LLR следующим образом:

, где

есть информационный бит LLR, предоставленный модулем 930 вычисления LLR для последней итерации обнаружения/декодирования. Двусторонний ограничитель 962 ограничивает итоговый информационный бит

LLR и предоставляет декодированный пакет

для восстанавливаемого пакета. Проверочное устройство 968 CRC проверяет декодированный пакет и предоставляет состояние пакета.After all N _dd detection / decoding iterations are completed, adder / multiplexer 960 calculates the resulting information bit

LLR as follows:

where

there is an LLR information bit provided by the LLR calculation unit 930 for the last iteration of detection / decoding. Two-way limiter 962 limits the total information bit

LLR and provides a decoded packet

for a recoverable package. CRC verification device 968 checks the decoded packet and provides packet status.

декодера от декодера 950 FEC перемежаются перемежителем 970 канала, и перемеженные LLR декодера предоставляются детектору 920. Детектор 920 извлекает новые обнаруженные символы

на основе принятых символов

и LLR

декодера. LLR

декодера используются для вычисления (а) ожидаемого значения взаимного влияния (то есть

), которое используется для получения

в равенстве (12), и (b) дисперсии взаимного влияния (то есть

), которая используется для получения

в равенстве (11).Returning back to FIG. 9A, LLR

the decoder from the FEC decoder 950 is interleaved with a channel interleaver 970, and the interleaved LLRs of the decoder are provided to the detector 920. The detector 920 extracts the new detected symbols

based on accepted characters

and LLR

decoder. LLR

decoders are used to calculate (a) the expected value of the mutual influence (i.e.

), which is used to obtain

in equality (12), and (b) the variance of the mutual influence (i.e.

), which is used to obtain

in equality (11).

для всех принятых блоков символов данных от пространственного процессора 160а приема снова декодируются процессором 170b принимаемых данных, как описано выше. Процесс обнаружения и декодирования повторяется N_dd раз. Во время итеративного процесса обнаружения и декодирования надежность обнаруженных символов усиливается с каждой итерацией обнаружения/декодирования.Detected Characters

for all received blocks of data symbols from the spatial receiving processor 160a are again decoded by the received data processor 170b, as described above. The detection and decoding process is repeated N _dd times. During the iterative process of detecting and decoding, the reliability of the detected symbols is enhanced with each iteration of detection / decoding.

детектора MMSE зависит от

, которая, в свою очередь, зависит от дисперсии взаимного влияния

. Поскольку

различна для каждой итерации обнаружения/декодирования, характеристика

детектора MMSE также различается для каждой итерации. Для упрощения приемника 150b детектор 920 может реализовать (1) детектор MMSE для N_dd1 итераций обнаружения/декодирования, и затем (2) детектор MRC (или какой-нибудь другой тип детектора/корректора, имеющего характеристику, которая не меняется с итерацией) для N_dd2 последующих итераций обнаружения/декодирования, где N_dd1 и N_dd2 каждый могут быть единицей либо больше. Например, детектор MMSE может использоваться для первой итерации обнаружения/декодирования, и детектор MRC может использоваться для следующих пяти итераций обнаружения/декодирования. В другом примере, детектор MMSE может использоваться для первых двух итераций обнаружения/декодирования, и детектор MRC может использоваться для следующих четырех итераций обнаружения/декодирования.As shown in equality (8), the characteristic

MMSE detector depends on

, which, in turn, depends on the variance of the mutual influence

. Insofar as

different for each iteration of detection / decoding, characteristic

MMSE detector also differs for each iteration. To simplify receiver 150b, detector 920 may implement (1) an MMSE detector for N _dd1 detection / decoding iterations, and then (2) an MRC detector (or some other type of detector / corrector having a characteristic that does not change with iteration) for N _dd2 subsequent iterations of detection / decoding, where N _dd1 and N _dd2 each may be one or more. For example, an MMSE detector can be used for the first iteration of detection / decoding, and an MRC detector can be used for the next five iterations of detection / decoding. In another example, an MMSE detector can be used for the first two detection / decoding iterations, and an MRC detector can be used for the next four detection / decoding iterations.

заменяет

. Как показано в равенствах (6), (9) и (12), составляющая u_i зависит от ожидаемого значения взаимного влияния

. Для дополнительного упрощения приемника 150b составляющая u_i может быть опущена после переключения с детектора MMSE на детектор MRC.The MRC detector can be implemented with component u _i , as shown in equality (6), where

replaces

. As shown in equalities (6), (9) and (12), the component u _i depends on the expected value of the mutual influence

. To further simplify the receiver 150b, the component u _i can be omitted after switching from the MMSE detector to the MRC detector.

An iterative detection and decoding scheme provides various advantages. For example, the IDD scheme supports the use of a single rate for all data packets transmitted simultaneously over N _T transmit antennas, can combat frequency selective attenuation, and can be flexibly used with various coding and modulation schemes, including the parallel-connected convolutional code shown in FIG. 4B .

3. Speed selection

For both single-carrier MIMO and MIMO-OFDM systems, the receiver and / or transmitter can evaluate the MIMO channel and selects the appropriate rate for data transmission on the MIMO channel. Speed selection can be performed in various ways. Some exemplary speed selection schemes are described below.

In the first rate selection scheme, a rate for transmitting data on a MIMO channel is selected based on a metric that is output using an equivalent system that models channel characteristics for N _T transmit antennas. An equivalent system is defined as having an AWGN channel (i.e., with a uniform frequency response) and spectral efficiency, which is equal to the average spectral efficiency N _{T of the} transmitting antennas. An equivalent system has a total throughput equal to the total throughput N _T transmit antennas. The average spectral efficiency can be determined by (1) estimating the received SBR for each transmit antenna (e.g., based on the received pilot symbol and / or data symbol), (2) calculating the spectral efficiency of each transmit antenna from the received SNR and on the basis of (limited or unlimited ) spectral efficiency functions f (x) and (3) calculating the average spectral efficiency N _{T of the} transmitting antennas based on the spectral efficiencies of the individual transmitting antennas. The metric can be defined as the SNR required by the equivalent system in order to maintain average spectral efficiency. This SNR can be determined from the average spectral efficiency and based on the inverse function f ^-1 (x).

The system can be designed to support multiple speeds. One of the supported speeds may be designed for zero speed (i.e., the data rate is zero). Each of the remaining rates is associated with a specific non-zero data rate, a specific coding scheme or code rate, a specific modulation scheme, and a specific minimum SNR required to achieve a given level of performance (e.g., 1% PER) for an AWGN channel. For each supported rate with a non-zero data rate, the required SNR is obtained based on a specific system design (i.e., a specific code rate, interleaving scheme, modulation scheme, and so on, used by the system for that rate) and for the AWGN channel. The required SNR can be obtained through computer simulation, empirical measurements, and so on, as is known in the art. Many supported speeds and their required SNRs can be stored in a look-up table (for example, LUT 184 in FIG. 8A).

The metric can be compared with the required SNR for each of the speeds supported by the system. The highest speed with the required SNR, which is less than or equal to the indicator, is selected for use for data transmission on the MIMO channel. The first speed selection scheme is described in detail in US Patent Application No. 10 / 176,567, entitled "Rate Control for Multi-Channel Communication Systems", registered June 20, 2002.

для N_T передающих антенн. Рабочее SNR

вычисляется следующим для N_T передающих антенн на основе среднего принятого SNR

, и смещения

SNR или фактора возврата в предыдущее состояние (например,

, где единицы в дБ). Смещение SBR используется для подсчета ошибки оценки, изменчивости в канале MIMO и других факторов. Рабочий SNR

может сравниваться по отношению к требуемому SNR для каждой из скоростей, поддерживаемых системой. Наивысшая скорость с требуемым SNR, которая меньше, либо равна рабочему SNR (то есть

), выбирается для использования для передачи данных по каналу MIMO. Вторая схема выбора скорости подробно описывается в Патентной заявке США номер 10/394,529, озаглавленной «Transmission Mode Selection for Data Transmission in a Multi-Channel Communication System» (Выбор режима передачи для передачи данных в многоканальной системе связи), зарегистрированной 20 марта 2003 г.In a second rate selection scheme, a rate for transmitting data on a MIMO channel is selected based on received SNRs for N _T transmit antennas. The received SNR for each transmit antenna is first determined, and then the average received SNR is calculated

for N _T transmit antennas. Work SNR

calculated as follows for N _T transmit antennas based on the average received SNR

, and offsets

SNR or return to previous state (e.g.

where units are in dB). The SBR offset is used to calculate the estimation error, variability in the MIMO channel, and other factors. Working SNR

can be compared with the required SNR for each of the speeds supported by the system. The highest speed with the required SNR, which is less than or equal to the working SNR (i.e.

), is selected for use for data transmission on the MIMO channel. The second speed selection scheme is described in detail in US Patent Application No. 10 / 394,529, entitled "Transmission Mode Selection for Data Transmission in a Multi-Channel Communication System", registered March 20, 2003.

The IR transmission techniques described herein may be implemented by various means. For example, these techniques may be implemented in hardware, software, or a combination thereof. For a hardware implementation, the processing modules used on the transmitter for IR transmission can be implemented in one or more specialized integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), programmable user gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, other electronic modules designed to perform the functions described here, or combinations thereof. The processing modules used at the receiver to receive IR transmission can also be implemented in one or more ASICs, DSPs, DSPDs, PLDs, FPGAs, processors, controllers, and so on.

For software implementation, IR transmission techniques can be implemented using modules (eg, procedures, functions, and so on) that perform the functions described here. Software codes may be stored in a memory module (e.g., memory modules 142 and 182 in FIG. 1) and executed by a processor (e.g., controllers 140 and 180). The memory module may be implemented within the processor or external to the processor, in which case it may be communicatively connected to the processor through various means, as is known in the art.

Headings are included herein for reference and to assist in locating specific sections. These headings are not intended to limit the scope of the concepts described below in the document, and these concepts may be applicable in other sections throughout the description of the invention.

The foregoing description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be 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 invention. Thus, the present invention is not intended to be limited to the embodiments shown in the materials of this application, but should correspond to the broadest scope consistent with the principles and new features disclosed in the materials of this application.

Claims (40)

1. The method of performing transmission with incremental redundancy (IR) in a wireless communication system with multiple inputs and multiple outputs (MIMO), namely, that
processing a data packet to obtain a plurality of symbol blocks for the data packet;
transmitting a first block of symbols from a plurality of transmit antennas at a transmitter to a plurality of receiving antennas at a receiver, the first block of symbols being one of a plurality of symbol blocks;
transmit the remaining blocks from the plurality of symbol blocks, one symbol block at a time, until the data packet is restored correctly by the receiver, or all of the plurality of symbol blocks will not be transmitted; and
transmit many of the data packets interlaced. 2. The method according to claim 1, in which additionally
get the selected speed for transmitting data on the MIMO channel between multiple transmit antennas and multiple receive antennas, and the data packet is processed in accordance with the selected speed. 3. The method according to claim 2, in which the processing includes the steps of
encode the data packet in accordance with the encoding scheme indicated by the selected rate to obtain an encoded packet, divide the encoded packet into a plurality of encoded
subpackages, and
modulating a plurality of coded subpackets in accordance with a modulation scheme indicated by a selected rate to obtain a plurality of symbol blocks. 4. The method according to claim 3, in which the coding scheme is a turbo code, and the first block of characters includes systematic bits for the data packet. 5. The method according to claim 1, in which additionally
accept a negative acknowledgment of receipt (NAK); and
transmitting the next block of symbols from the remaining blocks of the plurality of symbol blocks in response to receiving a NAK. 6. The method according to claim 1, wherein the MIMO system uses orthogonal frequency division multiplexing (OFDM), and while transmitting, each of the plurality of symbol blocks is transmitted from a plurality of subbands of a plurality of transmit antennas. 7. The method according to claim 2, in which each of the at least two data packets is processed in accordance with the selected speed to obtain at least two sets of symbol blocks, one set of symbol blocks for each data packet, and this, at least two symbol blocks for at least two data packets are transmitted simultaneously from multiple transmit antennas to multiple receive antennas. 8. The method of performing transmission with incremental redundancy (IR) in a wireless communication system with multiple inputs and multiple outputs (MIMO), namely, that
processing a data packet to obtain a plurality of symbol blocks for the data packet;
transmitting a first block of symbols from a plurality of transmit antennas at a transmitter to a plurality of receiving antennas at a receiver, the first block of symbols being one of a plurality of symbol blocks;
transmit the remaining blocks from the plurality of symbol blocks, one symbol block at a time, until the data packet is restored correctly by the receiver, or all of the plurality of symbol blocks are transmitted, and the MIMO system uses orthogonal frequency division multiplexing (OFDM), and each of at least two symbol blocks for at least two data packets are transmitted diagonally through a plurality of subbands and a plurality of transmit antennas. 9. The method of performing transmission with incremental redundancy (IR) in a wireless communication system with multiple inputs and multiple outputs (MIMO), namely, that
processing a data packet to obtain a plurality of symbol blocks for the data packet;
transmitting a first block of symbols from a plurality of transmit antennas at a transmitter to a plurality of receiving antennas at a receiver, the first block of symbols being one of a plurality of symbol blocks;
transmit the remaining blocks from the plurality of symbol blocks, one symbol block at a time, until the data packet is restored correctly by the receiver, or all of the plurality of symbol blocks will not be transmitted;
moreover, the MIMO system uses orthogonal frequency division multiplexing (OFDM), wherein each of N _{p of} said data packets is processed in accordance with a selected speed to obtain N _p sets of said symbol blocks, one set of said symbol blocks for each said data packet, N _p is greater than or equal to one and is selected based on the rank MIMO channel, and wherein said blocks N _p N _p symbols for the data packets are transmitted simultaneously diagonally across a plurality of subbands, and the set of transmit antennas. 10. The transmitter, configured to transmit with incremental redundancy (IR) in a wireless communication system with many inputs and many outputs (MIMO), containing
a transmit data processor configured to process a data packet to obtain a plurality of symbol blocks for the data packet;
and a controller configured to start transmitting a first symbol block from a plurality of transmit antennas at a transmitter to a plurality of receiving antennas at a receiver, the first symbol block being one of a plurality of symbol blocks, triggering a transmission of remaining blocks of a plurality of symbol blocks, one symbol block at a time, the data packet will not be restored correctly by the receiver, or all of the multiple blocks will not be transmitted; and
transmit many of the data packets interlaced. 11. The transmitter of claim 10, in which the processor of the transmitted data is configured to
encoding a data packet in accordance with an encoding scheme indicated by a selected rate to obtain an encoded packet,
dividing the encoded packet into a plurality of encoded subpackets, and
modulating a plurality of coded subpackets in accordance with a modulation scheme indicated by a selected rate to obtain a plurality of symbol blocks. 12. The transmitter of claim 10, further comprising a spatial transmit processor configured to receive a block of symbols to be transmitted and provide symbols in a block of symbols to a plurality of transmit antennas. 13. A transmission device, configured to transmit with incremental redundancy (IR) in a wireless communication system with multiple inputs and multiple outputs (MIMO), containing
means for processing the data packet to obtain a plurality of symbol blocks for the data packet;
means for transmitting a first block of symbols from a plurality of transmitting antennas at a transmitter to a plurality of receiving antennas at a receiver, the first block of symbols being one of a plurality of symbol blocks; and
means for transmitting the remaining blocks from the plurality of symbol blocks, one symbol block at a time, until the data packet is restored correctly by the receiver, or all of the plurality of symbol blocks will not be transmitted; and
means for transmitting the plurality of said data packets interlaced. 14. The device according to item 13, in which the processing means includes
means for encoding a data packet in accordance with an encoding scheme indicated by a selected rate to obtain an encoded packet,
means for splitting an encoded packet into a plurality of encoded subpackets, and
means for modulating a plurality of coded subpackets in accordance with a modulation scheme indicated by a selected rate to obtain a plurality of symbol blocks. 15. The method of receiving transmission with incremental redundancy (IR) in a wireless communication system with multiple inputs and multiple outputs (MIMO), namely, that
receiving a block of detected symbols for a data packet, the block of detected symbols being an estimate of a block of data symbols transmitted from a plurality of transmit antennas at a transmitter and received by a plurality of receiving antennas at a receiver, wherein the data symbol block is one of a plurality of data symbol blocks generated for a packet data;
decode all blocks of detected symbols received for the data packet to provide a decoded packet;
determining whether the decoded packet is error-free or in error;
retrieving, decoding, and determining for another block of the plurality of data symbol blocks if the decoded packet is in error; and
receive many of the data packets interlaced. 16. The method according to clause 15, in which additionally
receiving a block of received symbols for a data symbol block; and detecting the received symbol block to obtain a detected symbol block. 17. The method according to clause 16, in which the detection is based on a minimum mean square error detector (MMSE), a maximum ratio combining detector (MRC), or a linear zeroing detector (ZF) of negligible coefficients. 18. The method according to clause 15, in which additionally
interrupt receiving, decoding and determining if the decoded packet is error-free, or if multiple blocks of data symbols for the data packet are transmitted. 19. The method according to clause 15, in which additionally
send an acknowledgment notification (ACK) for the data symbol block if the decoded packet is error free, or a negative acknowledgment notification (NAK) if the decoded packet is in error. 20. The method according to clause 15, in which additionally
obtaining channel estimates for the MIMO channel between the plurality of transmit antennas and the plurality of receive antennas; and
based on the channel estimates, the rate for transmitting data on the MIMO channel is selected. 21. The method of receiving transmission with incremental redundancy (IR) in a wireless communication system with multiple inputs and multiple outputs (MIMO), namely, that
receiving a block of detected symbols for a data packet, wherein the block of detected symbols is an estimate of a block of data symbols transmitted from a plurality of transmit antennas at a transmitter and received by a plurality of receiving antennas at a receiver, and the data symbol block is one of a plurality of data symbol blocks generated for a packet data;
decode all blocks of detected symbols obtained for a data packet to provide a decoded packet;
determining whether the decoded packet is error-free or in error;
retrieving, decoding, and determining for another block of the plurality of data symbol blocks if the decoded packet is in error,
deriving a signal-to-noise-and-noise ratio (SNR) estimate for each of the plurality of transmit antennas,
determining an average spectral efficiency for a plurality of transmit antennas based on SNR estimates for a plurality of transmit antennas, and
determining a rate for transmitting data based on average spectral efficiency for a plurality of transmit antennas. 22. The method according to claim 20, in which the selection includes the steps of
deriving a signal-to-noise-and-noise ratio (SNR) estimate for each of the plurality of transmit antennas,
calculate the average SNR based on SNR estimates for multiple transmit antennas,
determine the factor of return to the previous state, and
determine the speed based on the average SNR and the previous return factor. 23. The receiver, configured to receive transmission with incremental redundancy (IR) in a wireless communication system with many inputs and many outputs (MIMO), containing
a received data processor configured to
receiving a block of detected symbols for a data packet, the block of detected symbols being an estimate of a block of data symbols transmitted from a plurality of transmit antennas at a transmitter and received by a plurality of receiving antennas at a receiver, wherein the data symbol block is one of a plurality of data symbol blocks generated for a packet data
decoding all blocks of detected symbols received for the data packet to provide a decoded packet, and
determining whether the decoded packet is error-free or in error; and
a controller configured to instruct the received data processor to retry receiving a new block of detected symbols, decoding all blocks of detected symbols and determining whether the decoded packet is error-free or with an error if the decoded packet is in error; and
a receiver for receiving the plurality of said data packets interlaced. 24. The receiver of claim 23, further comprising
a detector configured to receive a block of received symbols for a block of data symbols and detect a received block of symbols to obtain a detected symbol block. 25. The receiver of claim 23, further comprising
a channel estimator configured to obtain channel estimates for the MIMO channel between the plurality of transmit antennas and the plurality of receive antennas; and
a speed selector configured to select, based on the estimates of the speed channel, for transmitting data on the MIMO channel. 26. A receiver for receiving transmission with incremental redundancy (IR) in a wireless communication system with multiple inputs and multiple outputs (MIMO), containing
means for obtaining a block of detected symbols for a data packet, the block of detected symbols being an estimate of a block of data symbols transmitted from a plurality of transmit antennas at a transmitter and received by a plurality of receiving antennas at a receiver, and the block of data symbols is one of a plurality of data symbol blocks generated for a data packet;
means for decoding all blocks of detected symbols received for the data packet to obtain a decoded packet;
means for determining whether the decoded packet is error-free or in error;
means for retrieving, decoding, and determining for another block of the plurality of data symbol blocks if the decoded packet is in error;
means for receiving the plurality of said data packets interlaced. 27. The device according to p, optionally containing
means for obtaining a block of received symbols for a block of data symbols; and
means for detecting a received block of characters to obtain a detected block of characters. 28. The method of receiving transmission with incremental redundancy (IR) in a wireless communication system with multiple inputs and multiple outputs (MIMO), namely, that
receiving a block of received symbols for a data packet, wherein the received symbol block is for a block of data symbols transmitted from a plurality of transmit antennas at a transmitter and received by a plurality of receiving antennas at a receiver, and the data symbol block is one of a plurality of data symbol blocks generated for a packet data;
detecting all received symbol blocks received for a data packet to obtain detected symbol blocks, one detected symbol block for each received symbol block;
decode the detected symbol blocks for the data packet to obtain decoder feedback information;
detecting and decoding for a plurality of iterations are performed, wherein decoder feedback information from decoding for the current iteration is used in detection for subsequent iterations; and
form a decoded packet based on the output from decoding for the last iteration of the many iterations;
moreover, the MIMO system uses orthogonal frequency division multiplexing (OFDM), and wherein each of at least two symbol blocks for at least two data packets is transmitted diagonally through a plurality of subbands and a plurality of transmit antennas. 29. The method according to p, in which additionally
determining whether the decoded packet is error-free or in error; and
repeat the reception, detection, decoding, execution, and generation for another block of a plurality of data symbol blocks if the decoded packet is in error, and if all of the plurality of data symbol blocks are not transmitted. 30. The method according to p, in which additionally
obtaining channel estimates for the MIMO channel between the plurality of transmit antennas and the plurality of receive antennas; and
based on the channel estimates, the rate for transmitting data on the MIMO channel is selected. 31. The method of claim 28, wherein the detection is based on a minimum mean square error (MMSE) detector, a maximum ratio combining (MRC) detector, or a linear nulling (ZF) detector of negligible coefficients. 32. The method according to p, in which the MMSE detector is used to detect for N iterations, and the MRC detector or ZF detector is used for detection after N iterations, where N is one or more. 33. A receiver configured to receive transmission with incremental redundancy (IR) in a wireless communication system with multiple inputs and multiple outputs (MIMO), comprising
a buffer configured to receive and store a block of received symbols for a data packet, the received symbol block being for a block of data symbols transmitted from a plurality of transmit antennas at a transmitter and received by a plurality of receiving antennas at a receiver, and the data symbol block is one of a plurality blocks of data symbols generated for the data packet;
a detector configured to detect all received symbol blocks received for the data packet to obtain detected symbol blocks, one detected symbol block for each received symbol block; and
a decoder configured to decode all detected symbol blocks for a data packet to obtain decoder feedback information,
wherein the detector and decoder are capable of detecting and decoding for multiple iterations, wherein the decoder feedback information from the decoder for the current iteration is used by the detector for the subsequent iteration, and a decoded packet is generated based on the output from the decoder for the last iteration from the many iterations , and
moreover, the MIMO system uses orthogonal frequency division multiplexing (OFDM), and wherein each of at least two symbol blocks for at least two data packets is transmitted diagonally across multiple subbands and multiple transmit antennas. 34. The receiver of claim 33, further comprising a controller configured to indicate to the buffer
receive and save another received symbol block for another block of the multiple data symbol blocks if the decoded packet is in error and if all of the many data symbol blocks are not transmitted and instructs the detector and decoder to detect and decode on all the received symbol blocks received for the data packet , to receive a decoded packet. 35. A receiver for receiving transmission with incremental redundancy (IR) in a wireless communication system with multiple inputs and multiple outputs (MIMO), containing
means for receiving a block of received symbols for a data packet, wherein the received symbol block is for a block of data symbols transmitted from a plurality of transmit antennas at a transmitter and received by a plurality of receiving antennas at a receiver, wherein the data symbol block is one of a plurality of data symbol blocks generated for a data packet;
means for detecting all received symbol blocks received for a data packet to obtain detected symbol blocks, one detected symbol block for each received symbol block;
means for decoding all detected symbol blocks for a data packet to obtain decoder feedback information;
means for performing detection and decoding for multiple iterations, wherein the decoder feedback information from decoding for the current iteration is used upon detection for subsequent iteration; and
means for generating a decoded packet based on decoder output from decoding for the last iteration of the many iterations,
moreover, the MIMO system uses orthogonal frequency division multiplexing (OFDM), and wherein each of at least two symbol blocks for at least two data packets is transmitted diagonally across multiple subbands and multiple transmit antennas. 36. The device according to p, optionally containing
means for determining whether the decoded packet is error-free or in error; and
means for repeating the reception, detection, decoding, execution, and generation for another block of a plurality of data symbol blocks, if the decoded packet is in error and all of the plurality of data symbol blocks are not transmitted. 37. The method of receiving data transmission in a wireless communication system with many inputs and many outputs (MIMO), which consists in the fact that
detecting received symbols for a data packet to obtain detected symbols;
decode the detected symbols to obtain decoder feedback information;
detection and decoding are performed for a plurality of iterations, wherein the decoder feedback information from decoding for the current iteration is used for detection for the subsequent iteration, while the detection is performed based on the minimum mean square error detector (MMSE) for the first N iterations, where N is one or more, and based on the maximum ratio combining detector (MRC) or the linear zeroing (ZF) detector of insignificant coefficients for the remaining iterations from the set of iterations;
form a decoded packet based on the output from decoding for the last iteration of the many iterations; and
receive many of the data packets interlaced. 38. The method according to clause 37, in which N is equal to one.
Priorities for items: 09.09.2003 according to claims 2, 3, 11, 14, 20, 25, 30; 12/18/2003 according to claims 1, 4-10, 12, 13, 15-19, 21-24, 26-29, 31-38.

Images