RU2351071C2 - Channel evaluation and spatial processing for tdd mimo systems - Google Patents

Abstract

FIELD: physics; communications.

SUBSTANCE: present invention pertains to communication techniques and can be used for channel evaluation and spatial processing for an MIMO system. During normal operation, a MIMO pilot-signal is transmitted to the first communication line and is used for evaluating channel response of the first communication line, which is resolved for obtaining a diagonal matrix of singular values and a first unitary matrix, containing left characteristic vectors of the first communication line and right characteristic vectors of the second communication line. A controlled reference signal (reference) is transmitted on the second communication line, using characteristic vectors of the first unitary matrix, and is processed so as to obtain a diagonal matrix and a second unitary matrix, containing left characteristic vectors of the second communication line and right characteristic vectors of the first communication line. Each unitary matrix can be used for spatial processing for receiving/transmitting data on both communication lines.

EFFECT: making out the difference in responses of receiving/transmitting circuits at the access point and user terminal.

60 cl, 6 dwg

Description

FIELD OF THE INVENTION

This invention, in General, relates to data transmission, and more specifically, to methods for performing channel estimation and spatial processing in time division duplex (TDD) systems with multiple inputs and multiple outputs (MIMO).

State of the art

. Каждый из независимых каналов N _S также называется пространственным подканалом или собственной модой MIMO канала и соответствует размерности. MIMO система может обеспечить улучшенные характеристики (например, увеличенную пропускную способность) если используются дополнительные размерности, созданные множеством передающих и приемных антенн.A MIMO system uses multiple (N _T ) transmit antennas, and multiple (N _R ) receive antennas for data transmission. A MIMO channel formed by transmitting N _T and receiving N _R antennas can be decomposed into independent channels N _S with

. Each of the independent channels N _{S is} also called a spatial subchannel or its own MIMO channel mode and corresponds to a dimension. A MIMO system can provide improved performance (for example, increased throughput) if additional dimensions created by multiple transmit and receive antennas are used.

In order to transmit data on one or several N _S eigenmodes of the MIMO channel, it is necessary to perform spatial processing at the receiver and usually also at the transmitter. Data streams transmitted from N _T transmit antennas are crossed with each other at receive antennas. Spatial processing attempts to separate data streams at the receiver so that they can be returned individually.

, где

обозначает перемещение М .To perform spatial processing, an accurate estimate of the channel response between the transmitter and receiver is required. For a TDD system, a downlink (i.e., a forward link) and an uplink (i.e., a reverse link) share the same frequency band between an access point and a user terminal. In this case, the responses of the downlink channel and the uplink channel can be adopted so as to be reciprocal with each other after the calibration has been performed (as described below) to make up the differences in the transmit and receive chains at the access point and user terminal. Thus, if H represents a channel response matrix from the antenna array A to the antenna array B, then the reciprocal channel implies that communication from the antenna array B to the antenna array A is provided by

where

denotes the movement of M.

Channel estimation and spatial processing for a MIMO system typically consumes most of the system resources. Therefore, there is a need in the art for techniques to efficiently perform channel estimation and spatial processing in a TDD MIMO system.

SUMMARY OF THE INVENTION

The methods provided herein are used to perform channel estimation and spatial processing in an efficient manner in a TDD MIMO system. For a TDD MIMO system, channel mutual characteristics can be used to simplify channel estimation and spatial processing at both the transmitter and receiver. Initially, the access point and user terminal in the system can perform a calibration in order to determine the differences in the responses of their transmit and receive chains and obtain correction factors used to account for the differences. Calibration can be performed to ensure that the “calibrated” channel, with correction factors applied, is reciprocal. Thus, a more accurate estimate of the second communication line can be obtained based on the estimate obtained for the first communication line.

During normal operation, a MIMO pilot (pilot) is transmitted (for example, by an access point) on the first communication line (i.e., downlink), and is used to obtain a channel response estimate for the first communication line. The channel response estimate can then be decomposed (for example, by a user terminal using a singular decomposition) in order to obtain a diagonal matrix of singular values and a first unitary matrix containing both left eigenvectors of the first communication line and right eigenvectors of the second communication line (for example, uplink). The first unitary matrix can be used in such a way as to perform spatial processing for transmitting data received on the first communication line as well as for transmitting data that was sent on the second communication line.

An adjustable reference signal (adjustable reference) can be transmitted on the second communication line using eigenvectors in the first unitary matrix. An adjustable reference signal (or an adjustable pilot signal) is a pilot signal transmitted on certain eigenmodes using eigenvectors used to transmit data. This adjustable reference signal can then be processed (for example, by an access point) in order to obtain a diagonal matrix and a second unitary matrix containing both left eigenvectors of the second communication line and right eigenvectors of the first communication line. The second unitary matrix can be used in such a way as to perform spatial processing for transmitting data received on the second communication line as well as for transmitting data that was sent on the first communication line.

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

Brief Description of the Drawings

Various aspects and features of the present invention are described below in connection with the following drawings, in which:

Figure 1 is a block diagram of an access point and a user terminal in a TDD MIMO system, in accordance with one embodiment of the invention;

2A depicts a block diagram of a transmit and receive circuit at an access point and a user terminal, in accordance with one embodiment of the invention;

FIG. 2B depicts the use of correction matrices to compose differences in transmit / receive circuits at an access point and a user terminal, in accordance with one embodiment of the invention;

3 depicts spatial processing for a downlink and an uplink for a spatial multiplexing method, in accordance with one embodiment of the invention;

4 depicts spatial processing for a downlink and an uplink for a beam control method, in accordance with one embodiment of the invention; and

5 depicts a process for performing channel estimation and spatial processing at an access point and user terminal, in accordance with one embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a block diagram of an embodiment of an access point 110 and a user terminal 150 in a TDD MIMO system 100. The access point 110 is equipped with N _ap transmit / receive antennas for receiving / transmitting data, and the user terminal 150 is equipped with N _ut transmit / receive antennas .

On the downlink, at access point 110, data processor (TX) 114 receives a data stream (i.e., information bits) from data source 112 and sends signals and other data from controller 130. TX data processor 114 formats, encodes, interleaves and modulates (i.e., symbol maps) data in order to provide modulation symbols. TX spatial processor 120 receives modulation symbols from TX data processor 114 and performs spatial processing to provide N _ap transmit symbol streams, one stream for each antenna. The TX spatial processor 120 also multiplexes into pilot symbols as appropriate (e.g., for calibration and normal operation).

Each modulator (MOD) 122 (which includes a transmission chain) receives and processes a respective symbol transmission stream in order to provide a corresponding modulated downlink signal. The modulated downlink signals N _ap from modulators 122a through 122ap are then transmitted from the antennas N _ap 124a-124ap, respectively.

At user terminal 150, antennas N _ut 152a-152ut receive transmitted downlink modulated signals, and each antenna provides a received signal to a corresponding demodulator (DEMOD) 154. Each demodulator 154 (which includes a receive circuit) performs processing in addition to in modulator 122, and provides received symbols. The spatial reception processor (RX) 160 then performs spatial processing of the received symbols from all demodulators 154a-154ut in order to provide returned symbols, which are estimates of the modulation symbols sent by the access point. The RX data processor 170 further processes (e.g., the symbol demaps, deinterleaves, and decryption) the returned symbols in order to provide decoded data. The decoded data may include the returned data stream, signaling, and so on, which may be provided to the data receiver 172 for storage and / or to the controller 180 for further processing.

The processing for the uplink may be the same or different from the processing for the downlink. Data and signal transmission are processed (e.g., encoded, interleaved, and modulated) by TX data processor 188 and further spatially processed by TX spatial processor 190, which also multiplexes into pilot symbols as appropriate (e.g., for calibration and normal operation). The pilot and symbol transmission from TX spatial processor 190 are further processed by modulators 154a-154ut in order to generate uplink modulated signals N _ut , which are then transmitted via antennas 152a-152ut to the access point.

At access point 110, uplink modulated signals are received by antennas 124a-124ap, demodulated by demodulators 122a-122ap, and processed by spatial RX processor 140 and RX data processor 142 in an additional way to that performed at the user terminal. Decoded data for the uplink may be provided to a data receiver 144 for storage and / or to a controller 130 for further processing.

Controllers 130 and 180 control the operation of various data processing units at the access point and user terminal, respectively. Memory units 132 and 182 store data and program codes used by controllers 130 and 180, respectively.

1. Calibration

For a TDD system, since the downlink and the uplink share the same frequency band, there is usually a high degree of correlation between the responses of the downlink channel and the uplink channel. Thus, the response matrices of the downlink channel and the uplink channel can presumably be mutually (i.e. transposed) from each other. However, the responses of the transmit / receive chains at the access point are typically not equal to the responses of the transmit / receive chains at the user terminal. For improved performance, differences can be determined and accounted for through calibration.

) обрабатываются цепью передачи 214 и передаются от антенн N _ap 124 по каналу MIMO. В терминале пользователя 150 сигналы нисходящей линии связи принимаются антеннами N _ul 152 и обрабатываются цепью приема 254 для того, чтобы обеспечить принятые символы (обозначенные вектором "прием"

). Для восходящей линии связи в терминале пользователя 150 символы (обозначенные вектором передачи

) обрабатываются цепью передачи 264 и передаются от антенн N _ut 152 по каналу MIMO. В точке доступа 110, сигналы восходящей линии связи принимаются антеннами N _ap 124 и обрабатываются цепью приема 224 для того, чтобы обеспечить принятые символы (обозначенные вектором приема

).FIG. 2A depicts a block diagram of a transmit and receive circuit at an access point 110 and a user terminal 150, in accordance with one embodiment of the invention. For the downlink at access point 110, the characters (indicated by the “transfer” vector

) are processed by the transmission chain 214 and transmitted from the antennas N _ap 124 on the MIMO channel. At user terminal 150, downlink signals are received by antennas N _ul 152 and processed by a receive circuit 254 in order to provide received symbols (indicated by a “receive” vector)

) For the uplink in the user terminal, 150 characters (indicated by the transmission vector

) are processed by the transmission chain 264 and transmitted from the antennas N _ut 152 on the MIMO channel. At access point 110, uplink signals are received by antennas N _ap 124 and processed by a receive circuit 224 in order to provide received symbols (indicated by a receive vector

)

в терминале пользователя (в отсутствии помех) может быть выражен как:For the downlink, the receive vector

in the user terminal (in the absence of interference) can be expressed as:

, Уравнение 1,

, Equation 1,

представляет собой вектор передачи с N _ар элементами для нисходящей линии связи;Where

represents a transmission vector with N _ar elements for the downlink;

представляет собой вектор приема с N _ut элементами;

represents a receive vector with N _ut elements;

представляет собой диагональную матрицу N _ар × N _ар с элементами для комплексных коэффициентов передачи, связанных с цепью передачи для антенн N _ap в точке доступа;

represents a diagonal matrix N _ar × N _ar with elements for complex transmission coefficients associated with the transmission chain for antennas N _ap at the access point;

представляет собой диагональную матрицу N _ut × N _ut с элементами для комплексных коэффициентов передачи, связанных с цепью приема для антенн N _ut в терминале пользователя; и

represents a diagonal matrix N _ut × N _ut with elements for complex transmission coefficients associated with a receive circuit for antennas N _ut in a user terminal; and

H is a downlink channel response matrix N _ut × N _ap .

The responses of the transmit / receive circuits and the MIMO channel are usually a function of frequency. For simplicity, an amplitude fading channel (i.e., with a flat frequency response) is allowed for subsequent differentiation.

в точке доступа (в отсутствии помех) может быть выражен как:For the uplink, the receive vector

at the access point (in the absence of interference) can be expressed as:

, Уравнение 2,

, Equation 2,

представляет собой вектор передачи с N _ut элементами для восходящей линии связи;Where

represents a transmission vector with N _ut elements for the uplink;

представляет собой вектор приема с N _ар элементами;

is a receive vector with N _ar elements;

представляет собой диагональную матрицу N _ut × N _ut с элементами для комплексных коэффициентов передачи, связанных с цепью передачи для антенн N _ut в терминале пользователя;

represents a diagonal matrix N _ut × N _ut with elements for complex transmission coefficients associated with the transmission chain for the antennas N _ut in the user terminal;

представляет собой диагональную матрицу N _ар × N _ар с элементами для комплексных коэффициентов передачи, связанных с цепью приема для N _ар антенн в точке доступа; и

represents a diagonal matrix of N _ar × N _ar with elements for complex transmission coefficients associated with the receive circuit for N _ar antennas at the access point; and

представляет собой матрицу ответа канала N _ар × N _ut для восходящей линии связи.

represents the channel response matrix N _ar × N _ut for the uplink.

и

, которые включают в себя ответы применяемых цепей приема и передачи, могут быть выражены как:From equations (1) and (2), the “effective” responses of the downlink channel and the uplink channel

and

, which include the responses of the applicable transmit and receive chains, can be expressed as:

и

Уравнение 3

and

Equation 3

As shown in equation (3), if the responses of the transmit / receive chains at the access point are not equal to the responses of the transmit / receive chains at the user terminal, then the effective responses of the downlink channel and the uplink channel are not mutually related, i.e.

Combining these two equations in the set of equation (3), the following relationships can be obtained:

Уравнение 4

Equation 4

By rearranging equation (4), the following is obtained:

or

Уравнение 5

Equation 5

и

. Так как

,

,

, и

являются диагональными матрицами,

и

также являются диагональными матрицами. Также уравнение (5) может быть выражено как:Where

and

. As

,

,

, and

are diagonal matrices,

and

are also diagonal matrices. Equation (5) can also be expressed as:

Уравнение 6

Equation 6

и

могут быть рассмотрены как, включающие в себя "поправочные коэффициенты", которые могут составлять различия в цепях приема/передачи в точке доступа и терминале пользователя. Тогда это позволило бы ответу канала для одной линии связи быть выраженным ответом канала для другой линии связи, как показано в уравнении (5).Matrices

and

may be considered as including “correction factors”, which may constitute differences in the transmit / receive chains at the access point and user terminal. Then this would allow the channel response for one communication line to be the expressed channel response for another communication line, as shown in equation (5).

и

. Как правило, истинный ответ канала H и ответы цепи приема/передачи не известны, и не могут быть точно или легко установлены. Вместо этого эффективные ответы канала нисходящей линии связи и канала восходящей линии связи

и

могут быть оценены основываясь на контрольных сигналах MIMO, посланных по нисходящей линии связи и на восходящей линии связи соответственно. Генерация и использование контрольного сигнала MIMO подробно описаны вышеупомянутой США заявке на патент № 60/421,309.Calibration can be performed to determine matrices

and

. Typically, the true response of channel H and the responses of the transmit / receive chain are not known, and cannot be accurately or easily established. Instead, the effective responses of the downlink channel and the uplink channel

and

can be estimated based on the MIMO pilots sent on the downlink and on the uplink, respectively. The generation and use of the MIMO pilot signal is described in detail in the aforementioned US patent application No. 60 / 421,309.

и

, которые упоминаются как матрицы коррекции

и

, могут быть получены на основании оценок ответа канала нисходящей линии связи и канала восходящей линии связи

и

в различных способах, включая вычисление матричного отношения и минимальной среднеквадратической ошибки (MMSE). Для вычисления матричного отношения, матрица

С сначала вычисляется как отношение оценок ответов канала нисходящей линии связи и канала восходящей линии связи следующим образом:Matrix Estimates

and

referred to as correction matrices

and

can be obtained based on the response estimates of the downlink channel and the uplink channel

and

in various ways, including calculating the matrix ratio and the minimum mean square error (MMSE). To calculate the matrix ratio, the matrix

C is first calculated as the ratio of the estimates of the responses of the downlink channel and the uplink channel as follows:

Уравнение 7,

Equation 7

where the relation is taken element-wise. Thus, each element of C can be calculated as:

, для

и

,

for

and

,

и

является (i,j)-м (ряд, колонка) элементом из

и

соответственно, и

представляет собой (i,j)-й элемент из С .Where

and

is the ( i, j ) -th (row, column) element of

and

respectively, and

represents the ( i, j ) th element of C.

для точки доступа, который включает в себя только диагональные элементы

из

, может быть определен так, чтобы быть равным значению нормализованных рядов С . Каждый ряд С ,

, сначала нормализован посредством разделения каждого элемента ряда с первым элементом ряда для того, чтобы получить соответствующий нормализованный ряд

. Таким образом, если

представляет собой i-й ряд из C , то нормализованный ряд

, может быть выражен как:Correction Vector

for an access point that includes only diagonal elements

of

It may be defined to be equal to the value of the normalized rows of C. Each row C ,

is first normalized by dividing each element of the row with the first element of the row in order to obtain the corresponding normalized row

. So if

represents the i-th row of C, then the normalized row

may be expressed as:

.

.

затем приравнивается к средним из

нормализованных рядов С и может быть выражен как:Correction Vector

then equated to the average of

normalized series C and can be expressed as:

Уравнение 8

Equation 8

является единством.Due to normalization, the first element of

is a unity.

для терминала пользователя,

, который включает в себя только диагональные элементы

из

, может быть определен так, чтобы быть равным средней из инверсий нормализованных колонок С . Каждая колонка из С ,

, сначала нормализована посредством измерения каждого элемента в колонке с j-м элементом вектора

, который обозначен как

для того, чтобы получить соответствующую нормализованную колонку

. Таким образом, если

является j-й колонкой из C , тогда нормализованная колонка

может быть выражена как:Correction Vector

 for user terminal,

which includes only diagonal elements

 of

can be defined to be equal to the average of the inversions of the normalized columns FROM . Each column of FROM ,

is first normalized by measuring each element in column cj-m element of vector

which is designated as

 in order to get the corresponding normalized column

. So if

is anjcolumn of C then normalized column

 may be expressed as:

затем устанавливается равным средней из инверсий из

нормализованных колонок из С и может быть выражен как:Correction Vector

then set equal to the average of the inversions of

normalized columns from C and can be expressed as:

Уравнение 9

Equation 9

выполнена поэлементно.where the inverse of normalized columns

executed element by element.

и

или соответствующие матрицы коррекции

и

для точки доступа и терминала пользователя соответственно.Calibration provides correction vectors

and

or corresponding correction matrices

and

for the access point and user terminal, respectively.

и

подробно описано в вышеупомянутой США заявке на патент № 60/421,462.MMSE calculation for correction matrices

and

described in detail in the aforementioned US patent application No. 60 / 421,462.

сначала умножается с матрицей

посредством блока 212. Последующая обработка цепью передачи 214 и цепью приема 254 для нисходящей линии связи является аналогичной показанной на Фиг.2А. Точно так же на восходящей линии связи вектор передачи

сначала умножается с матрицей

посредством блока 262. К тому же последующая обработка цепью передачи 264 и цепью приема 224 для восходящей линии связи является аналогичной показанной на Фиг.2А.FIG. 2B illustrates the use of correction matrices for counting differences in transmit / receive circuits at an access point and user terminal, in accordance with one embodiment of the invention. Downlink transmission vector

first multiplied with matrix

by block 212. Subsequent processing by the transmit chain 214 and the receive chain 254 for the downlink is similar to that shown in FIG. 2A. Similarly, on the uplink transmission vector

first multiplied with matrix

by block 262. In addition, subsequent processing by the transmit chain 264 and the receive chain 224 for the uplink is similar to that shown in FIG. 2A.

The “calibrated” responses of the downlink channel and the uplink channel observed by the user terminal and access point, respectively, can be expressed as:

и

, Уравнение 10

and

, Equation 10

и

представляют собой оценки "истинных" выражений ответа калиброванного канала в уравнении (6). Из уравнений (6) и (10) может быть выявлено, что

. Точность отношений

зависит от точности оценок

и

, которые в свою очередь зависят от качества оценок ответа канала нисходящей линии связи и канала восходящей линии связи

и

. Как показано выше, как только цепи приема/передачи были калиброваны, оценка ответа калиброванного канала полученная для одной линии связи (например,

), может быть использована как оценка ответа калиброванного канала для другой линии связи (например,

).Where

and

are estimates of the "true" expressions of the response of the calibrated channel in equation (6). From equations (6) and (10) it can be revealed that

. Relationship accuracy

depends on the accuracy of the estimates

and

, which in turn depend on the quality of the response estimates of the downlink channel and the uplink channel

and

. As shown above, as soon as the transmit / receive circuits were calibrated, a response estimate of the calibrated channel obtained for one communication line (for example,

) , can be used as an estimate of the response of a calibrated channel for another communication line (for example,

)

Calibration for the TDD MIMO system is described in detail in the aforementioned US patent application No. 60 / 421,309, and US patent application No. 60 / 421,462.

2. Spatial Processing

For a MIMO system, data can be transmitted on one or more eigenmodes of the MIMO channel. The spatial multiplexing method can be defined in order to cover data transmission on many eigenmodes, and the beam control method can be determined in order to cover data transmission on a single eigenmode. Both working methods require spatial processing at the transmitter and receiver.

), которые также называются элементами разрешения по частоте или подканалами. С OFDM, каждая(ый) подполоса (поддиапазон) связана с соответствующей поднесущей, на которой могут быть модулированы данные. Для MIMO системы, использующей OFDM (т.е. MIMO-OFDM система), каждая собственная мода каждой подполосы может быть рассмотрена как независимый канал передачи. Для ясности, оценка канала и пространственные методы обработки описаны ниже для TDD MIMO-OFDM системы. Для этой системы, каждая подполоса беспроводного канала может быть предположена так, чтобы быть взаимной.Channel estimation and spatial processing techniques described herein can be used for MIMO systems with or without OFDM. OFDM effectively divides the overall system bandwidth into multiple orthogonal subbands (subbands) (

) , which are also called frequency resolution elements or subchannels. With OFDM, each subband (subband) is associated with a corresponding subcarrier on which data can be modulated. For a MIMO system using OFDM (i.e., a MIMO-OFDM system), each eigenmode of each subband can be considered as an independent transmission channel. For clarity, channel estimation and spatial processing techniques are described below for a TDD MIMO-OFDM system. For this system, each subband of the wireless channel can be assumed to be mutual.

The correlation between the responses of the downlink channel and the uplink channel can be used to simplify channel estimation and spatial processing at the access point and user terminal for the TDD system. This simplification is effective after the calibration has been performed in order to make up the differences in the transmit / receive circuits. The responses of a calibrated channel can be expressed as a function of frequency, as follows:

, для

,

for

,

, для

, Уравнение 11 and

for

, Equation 11

и

были получены для каждой из подполос данных. Альтернативно, калибровка может быть выполнена только для подмножества всех подполос данных, когда матрицы

и

для "некалиброванных" подполос могут быть получены, интерполируя матрицы для "калиброванных" подполос, как описано в вышеупомянутой США заявке на патент № 60/421,462.where K represents a series of all subbands that can be used to transmit data (ie, "data subbands"). Calibration can be performed so that the matrices

and

were obtained for each of the data subbands. Alternatively, calibration can only be performed for a subset of all data subbands when matrices

and

for "non-calibrated" subbands can be obtained by interpolating matrices for "calibrated" subbands, as described in the aforementioned US patent application No. 60 / 421,462.

для каждой подполосы может быть "диагонализуемой " для того, чтобы получить N _s собственных мод для той подполосы. Это может быть достигнуто либо посредством выполнения сингулярной декомпозиции на матрице ответа канала

либо посредством разложения собственного значения на матрице корреляции из

, являющейся

. Для ясности, сингулярная декомпозиция используется для следующего описания.Channel Response Matrix

for each subband can be "diagonalizable" in order to get N _s eigenmodes for that subband. This can be achieved either by performing a singular decomposition on the channel response matrix

either by expanding the eigenvalue on the correlation matrix from

which is

. For clarity, a singular decomposition is used for the following description.

может быть выражена как:Singular decomposition of a matrix of a calibrated response of the uplink channel

may be expressed as:

, для

Уравнение(12)

for

Equation (12)

представляет собой унитарную матрицу (N _ap × N _ap) левых собственных векторов из

;Where

is a unitary matrix ( N _ap × N _ap ) of left eigenvectors from

;

представляет собой диагональную матрицу (N _ap × N _ut) сингулярных значений из

и;

is a diagonal matrix ( N _ap × N _ut ) of singular values from

and;

представляет собой унитарную матрицу (N _ut × N _ut) правых собственных векторов из

.

is a unitary matrix ( N _ut × N _ut ) of right eigenvectors from

.

,где

представляет собой матрицу идентичности.The unitary matrix is characterized by property

,Where

is an identity matrix.

может быть выражена как:Accordingly, a singular decomposition of a calibrated downlink response matrix

may be expressed as:

, для

, Уравнение (13)

for

, Equation (13)

и

являются унитарными матрицами левых и правых собственных векторов соответственно из

. Как показано в уравнениях (12) и (13) и основано на вышеупомянутом описании, матрицы левых и правых собственных векторов для одной линии связи являются комплексом, сопряженным из матриц правых и левых собственных векторов, соответственно, для другой линии связи. Матрицы

,

,

и

являются различными формами матрицы

, и матрицы

,

,

и

- также являются различными формами матрицы

. Для простоты, ссылка на матрицы

и

в следующем описании может также может быть сделана к их различным другим формам. Матрицы

и

используются точкой доступа и терминалом пользователя соответственно, для пространственной обработки и обозначены также их подписями. Собственные векторы также часто называются "регулируемыми" векторами.where are the matrices

and

are unitary matrices of left and right eigenvectors respectively from

. As shown in equations (12) and (13) and based on the above description, the matrix of left and right eigenvectors for one communication line are a complex conjugate of the matrices of right and left eigenvectors, respectively, for another communication line. Matrices

,

,

and

are different forms of matrix

, and matrices

,

,

and

- are also different forms of matrix

. For simplicity, a link to the matrix

and

the following description can also be made to their various other forms. Matrices

and

are used by the access point and user terminal, respectively, for spatial processing and are also indicated by their signatures. Eigenvectors are also often referred to as “regulated” vectors.

A singular decomposition is described in detail by Hilbert Strang in a book entitled “Linear Algebra and Its Applications,” Second Edition, Academic Press, 1980.

, для

, для того, чтобы получить диагональную матрицу

и матрицу

левых собственных векторов из

. Эта сингулярная декомпозиция может быть представлена как

, где шапка

над каждой матрицей указывает то, что это оценка фактической матрицы.The user terminal may evaluate a calibrated downlink channel response based on the MIMO pilot transmitted by the access point. Then, the user terminal may perform a singular decomposition to evaluate the calibrated response of the downlink channel

for

, in order to get the diagonal matrix

and matrix

left eigenvectors from

. This singular decomposition can be represented as

where is the hat

above each matrix indicates that it is an estimate of the actual matrix.

, для

, для того, чтобы получить диагональную матрицу

и матрицу

левых собственных векторов из

. Эта сингулярная декомпозиция может быть представлена как

.Similarly, the access point can evaluate the calibrated uplink channel response based on the MIMO pilot transmitted by the user terminal. Then the access point can perform a singular decomposition to evaluate the calibrated response of the uplink channel

for

In order to obtain a diagonal matrix

and matrix

left eigenvectors from

. This singular decomposition can be represented as

.

, для

, используется для пространственной обработки в терминале пользователя, и матрица

, для

, может быть обеспечена в точке доступа в любой прямой форме (т.е. посылая элементы матриц

) или косвенной форме (например, через регулируемую ссылку, как описано ниже).However, due to the mutual channel and calibration, the singular decomposition should be performed only by the user terminal or access point. If executed by the user terminal, then the matrix

for

is used for spatial processing in the user terminal, and the matrix

for

, can be provided at the access point in any direct form (i.e., sending matrix elements

) or in indirect form (for example, through a regulated link, as described below).

, для

, может быть задано такое, что первая колонка содержит наибольшее сингулярное значение, вторая колонка содержит следующее наибольшее сингулярное значение, и так далее (т.е.

, где

является собственным значением в i-й колонке

после задания). Когда сингулярные значения для каждой матрицы

заданы, собственные векторы (или колонки) связанных унитарных матриц

и

для той подполосы, также задаются соответственно. "Широкополосная" собственная мода может быть определена как набор того же самого порядка собственных мод всех подполос после упорядочения (т.е. m-я широкополосная собственная мода включает в себя m-е собственные моды всех подполос). Каждая широкополосная собственная мода связана с соответствующим набором собственных векторов для всех подполос. Основная широкополосная собственная мода представляет собой собственную моду, связанную с наибольшим сингулярным значением в каждой матрице

после упорядочения.The singular values in each matrix

for

, can be set such that the first column contains the largest singular value, the second column contains the next largest singular value, and so on (i.e.

where

is an eigenvalue in the i- th column

after the assignment). When the singular values for each matrix

given eigenvectors (or columns) of connected unitary matrices

and

for that subband, are also set accordingly. A “wideband” eigenmode can be defined as a set of the same order of eigenmodes of all subbands after ordering (i.e., the mth wideband eigenmode includes the mth eigenmodes of all subbands). Each broadband eigenmode is associated with a corresponding set of eigenvectors for all subbands. The main broadband eigenmode is the eigenmode associated with the largest singular value in each matrix

after streamlining.

A. Uplink Spatial Processing

Spatial processing by a user terminal for uplink transmission can be expressed as:

, для

Уравнение 14

for

Equation 14

представляет собой вектор передачи для восходящей линии связи для k-й подполосы; иWhere

represents an uplink transmission vector for the kth subband; and

представляет собой вектор "данных" с до N _s элементами, отличными от нуля, для символов модуляции, которые будут переданы на N _s собственных модах k-й подполосы.

represents a vector of “data” with up to N _s non-zero elements for modulation symbols that will be transmitted to N _s eigenmodes of the kth subband.

The received uplink transmission at the access point may be expressed as:

, для

Уравнение 15

for

Equation 15

представляет собой принятый вектор для восходящей линии связи для k-й подполосы; иWhere

represents the received vector for the uplink for the k- th subband; and

представляет собой совокупные белые Гауссовы помехи (AWGN) для k-й подполосы.

represents the aggregate white Gaussian interference (AWGN) for the kth subband.

и

.Equation (15) uses the following relationships:

and

.

для передачи восходящей линии связи от терминала пользователя может быть выражена как:Matched Filter Matrix

for uplink transmission from a user terminal may be expressed as:

, для

Уравнение 16

for

Equation 16

The spatial processing (or matched filtering) at the access point for the received uplink transmission can be expressed as:

для

Уравнение 17

for

Equation 17

представляет собой оценку вектора данных

, переданную терминалом пользователя по восходящей линии связи, и

представляет собой постобработанные помехи.Where

is an estimate of the data vector

transmitted by the user terminal on the uplink, and

represents post-processed interference.

B. Downlink Spatial Processing

Spatial processing by an access point for downlink transmission can be expressed as:

, для

, Уравнение 18

for

, Equation 18

представляет собой вектор передачи, и

представляет собой вектор данных для нисходящей линии связи.Where

represents the transfer vector, and

is a data vector for the downlink.

The received downlink transmission in the user terminal may be expressed as:

,для

, Уравнение 19

for

, Equation 19

для передачи нисходящей линии связи от точки доступа может быть выражена как:Matched Filter Matrix

for downlink transmission from an access point can be expressed as:

, для

Уравнение 20

for

Equation 20

Spatial processing (or matched filtering) in a user terminal for a received downlink transmission can be expressed as:

, для

Уравнение 21

for

Equation 21

The table summarizes the spatial processing at the access point and user terminal for receiving and transmitting data.

Uplink Downlink User terminal Broadcast: Reception:

Access point Reception: Broadcast:

и

применены на стороне передачи в точке доступа и терминале пользователя соответственно. Матрицы коррекции

и

могут также быть объединены с другими диагональными матрицами (например, типа весовых матриц

и

используемых для достижения инверсии канала). Однако матрицы коррекции также могут быть применены на сторону приема, вместо стороны передачи, и это находится в рамках изобретения.In the above description and as shown in the table, correction matrices

and

applied on the transmission side at the access point and user terminal, respectively. Correction matrices

and

can also be combined with other diagonal matrices (e.g., type weight matrices

and

used to achieve channel inversion). However, correction matrices can also be applied to the receive side, instead of the transmit side, and this is within the scope of the invention.

FIG. 3 is a block diagram of a spatial processing for a downlink and an uplink for a spatial multiplexing method, in accordance with one embodiment of the invention.

, для

, сначала умножается с матрицей

посредством блока 310 и затем дополнительно умножается с матрицей коррекции

посредством блока 312 для того, чтобы получить вектор передачи

. Вектор

, для

, затем обрабатывается цепью передачи 314 в модуляторе 122x и передается по каналу MIMO на терминал пользователя 150x. Блок 310 выполняет пространственную обработку для передачи данных нисходящей линии связи.For the downlink in the TX spatial processor 120x of the access point 110x, the data vector

for

is first multiplied with the matrix

by block 310 and then further multiplied with a correction matrix

by block 312 in order to obtain a transmission vector

. Vector

for

, then processed by the transmission chain 314 in the modulator 122x and transmitted over the MIMO channel to the user terminal 150x. Block 310 performs spatial processing for transmitting downlink data.

, для

. В пространственном RX процессоре 160x, вектор приема

, для

, сначала умножается с матрицей

посредством блока 356 и дополнительно измеряется обратной диагональной матрицей

посредством блока 358 для того, чтобы получить вектор

, который является оценкой вектора данных

. Блоки 356 и 358 выполняют пространственную обработку для подобранной фильтрации нисходящей линии связи.In the user terminal 150x, the downlink signals are processed by the receive circuit 354 in the demodulator 154x in order to obtain a receive vector

for

. In a spatial RX processor 160x, receive vector

for

is first multiplied with the matrix

by block 356 and additionally measured by the inverse diagonal matrix

by block 358 in order to obtain a vector

Which is an estimate of the data vector

. Blocks 356 and 358 perform spatial processing for matched downlink filtering.

, для

, сначала умножается с матрицей

посредством блока 360 и затем дополнительно умножается с матрицей коррекции

посредством блока 362 для того, чтобы получить вектор передачи

. Вектор

, для

, затем обрабатывается цепью передачи 364 в модуляторе 154x и передается по каналу MIMO в точку доступа 110x. Блок 360 выполняет пространственную обработку для передачи данных восходящей линии связи.For uplink in TX spatial processor 190x of user terminal 150x, data vector

for

is first multiplied with the matrix

by block 360 and then further multiplied with a correction matrix

by block 362 in order to obtain a transmission vector

. Vector

for

, then processed by the transmission chain 364 in the modulator 154x and transmitted on the MIMO channel to the access point 110x. Block 360 performs spatial processing for transmitting uplink data.

, для

. В пространственном RX процессоре 140x вектор приема

, для

, сначала умножается с матрицей

посредством блока 326 и дополнительно измеряется обратной диагональной матрицей

посредством блока 328 для того, чтобы получить вектор

, который является оценкой вектора данных

. Блоки 326 и 328 выполняют пространственную обработку для согласованной фильтрации восходящей линии связи.At access point 110, the uplink signals are processed by receive chain 324 in demodulator 122x in order to obtain a receive vector

for

. In a spatial RX processor 140x receive vector

for

is first multiplied with the matrix

by block 326 and additionally measured by the inverse diagonal matrix

by block 328 in order to obtain a vector

which is an estimate of the data vector

. Blocks 326 and 328 perform spatial processing for matched uplink filtering.

3. Beam adjustment

For certain channel modes, it is better to transmit data only on one broadband eigenmode — usually the best or primary broadband eigenmode. This may be the case if the received signal-to-interference ratios (SNRs) for all other broadband eigenmodes are bad enough for improved performance to be achieved by using all available transmit energy on the main broadband eigenmode.

или

, для

, для основной широкополосной собственной моды (т.е. первая колонка

или

, после задания). Для регулирования луча символы модуляции пространственно обрабатываются с рядом "нормализованных" (или "насыщенных"), собственных векторов

или

, для

, для основной широкополосной собственной моды. Для ясности, регулирование луча описано ниже для восходящей линии связи.Data transmission on one wideband eigenmode can be achieved using either beamforming or beam steering. To form a beam, the modulation symbols are spatially processed with eigenvectors

or

for

, for the main broadband eigenmode (i.e., the first column

or

after the assignment). To control the beam, the modulation symbols are spatially processed with a number of “normalized” (or “saturated”) eigenvectors

or

for

, for the main broadband native fashion. For clarity, beam control is described below for the uplink.

, для

, для основной широкополосной собственной моды, могут иметь различные величины. Таким образом, предобусловленные символы для каждой подполосы, которые получены, посредством умножения символа модуляции для подполосы k с элементами собственного вектора

для подполосы k, могут тогда иметь различные величины. Следовательно, per-антенна передает векторы, каждый из которых включает в себя предварительно кондиционированные символы для всех подполос данных к антенне передачи, могут иметь различные величины. Если переданная мощность для каждой антенны передачи ограничена (например, из-за ограничений усилителей мощности), то формирование луча, возможно, полностью не использует полную мощность, доступную для каждой антенны.For the uplink, elements of each eigenvector

for

, for the main broadband eigenmode, can have different values. Thus, the preconditioned symbols for each subband that are obtained by multiplying the modulation symbol for subband k with eigenvector elements

for subband k, can then have different values. Therefore, the per-antenna transmits vectors, each of which includes pre-conditioned symbols for all data subbands to the transmission antenna, can have different values. If the transmitted power for each transmission antenna is limited (for example, due to the limitations of power amplifiers), then beamforming may not fully utilize the full power available for each antenna.

, для

, для основной широкополосной собственной моды и нормализует каждый собственный вектор так, что все элементы в собственном векторе имеют равные величины. Нормализованный собственный вектор

для k-й подполосы может быть выражен как:Beam control uses only phase information from eigenvectors

for

, for the main broadband eigenmode and normalizes each eigenvector so that all elements in the eigenvector have equal values. Normalized Eigenvector

for the k- th subband can be expressed as:

, Уравнение 22

, Equation 22

where A is a constant (for example, A = 1); and

представляет собой фазу для k-й подполосы j-й антенны передачи, которая дается как:

represents the phase for the kth subband of the jth transmission antenna, which is given as:

Уравнение 23

Equation 23

получена от соответствующего элемента собственного вектора

(т.е.

получен от

где

As shown in equation (23), the phase of each element in the vector

obtained from the corresponding element of the eigenvector

(those.

received from

Where

A. Uplink Beam Regulation

Spatial processing by a user terminal for uplink beam control can be expressed as:

, для

Уравнение 24

for

Equation 24

представляет собой символ модуляции, который будет передан на k-й подполосе; и

представляет собой вектор передачи для k-й подполосы для регулирования луча.Where

represents the modulation symbol to be transmitted on the k-th subband; and

represents the transmission vector for the kth subband for beam control.

для каждой подполосы имеют равную величину, но возможно различные фазы. Регулирование луча таким образом генерирует каждый вектор передачи

для каждой подполосы с элементами N _ut из

имеющий ту же самую величину, но возможно различные фазы.As shown in equation (22), the elements N _{ut of the} normalized controlled vector

for each subband, they are of equal magnitude, but different phases are possible. Beam control thus generates each transmission vector

for each subband with elements N _ut from

having the same magnitude but possibly different phases.

The received uplink transmission at the access point for beam control can be expressed as:

, для

, Уравнение 25

for

, Equation 25

представляет собой принятый вектор для канала восходящей связи для k-й подполосы для регулирования луча.Where

represents the received vector for the uplink for the kth subband for beam control.

для передачи по восходящей линии связи, использующий регулирование луча может быть выражен как:Matched Filter String Vector

for uplink transmission using beam control can be expressed as:

, для

. Уравнение 26

for

. Equation 26

может быть получен как описано ниже. Пространственная обработка (или согласованная фильтрация) в точке доступа для принятой передачи по восходящей линии связи с регулированием луча может быть выражена как:Matched Filter Vector

can be obtained as described below. Spatial processing (or matched filtering) at the access point for received uplink transmission with beam control can be expressed as:

, для

, Уравнение 27

for

, Equation 27

(т.е.,

представляет собой скалярное произведение

и его сопряженного перемещения),Where

(those.,

is a scalar product

and its associated displacement),

представляет собой оценку символа модуляции

, переданного терминалом пользователя по восходящей линии связи, и

is an estimate of the modulation symbol

Transmitted by the user terminal on the uplink, and

представляет собой постобработанные помехи.

represents post-processed interference.

B. Downlink beam control

Spatial processing by an access point for downlink beam control can be expressed as:

, для

, Уравнение 28

for

, Equation 28

представляет собой нормализованный собственный вектор для k-й подполосы, который сгенерирован основываясь на собственном векторе

для основной широкополосной собственной моды, как описано выше.Where

represents the normalized eigenvector for the kth subband, which is generated based on the eigenvector

for the main broadband eigenmode as described above.

для передачи по нисходящей линии связи, используя регулирование луча, может быть выражен как:Matched Filter String Vector

for downlink transmission using beam control, can be expressed as:

, для

Уравнение 29

for

Equation 29

Spatial processing (or matched filtering) in a user terminal for a received downlink transmission can be expressed as:

для

, Уравнение 30

for

, Equation 30

(т.е.,

представляет собой скалярное произведение

и его сопряженного перемещения).Where

(those.,

is a scalar product

and its associated displacement).

Beam control can be considered as a special case of spatial processing, in which only one eigenvector for one eigenmode is used to transmit data, and this eigenvector is normalized in order to have equal values.

FIG. 4 is a block diagram of a spatial processing for a downlink and an uplink for a beam-steering method, in accordance with one embodiment of the invention.

, для

, сначала умножается с нормализованным собственным вектором

(k) блоком 410 и затем дополнительно умножается с матрицей коррекции

блоком 412 для того, чтобы получить вектор передачи

. Вектор

, для

, затем обрабатывается цепью передачи 414 в модуляторе 122y и передается по MIMO каналу на терминал пользователя 150y. Блок 410 выполняет пространственную обработку для передачи данных по нисходящей линии связи для регулирующего луч способа.For the downlink in the TX spatial processor 120y of the access point 110y, a modulation symbol

for

is first multiplied with the normalized eigenvector

( k) block 410 and then further multiplied with a correction matrix

block 412 in order to obtain a transmission vector

. Vector

for

, then processed by transmission chain 414 in modulator 122y and transmitted over the MIMO channel to user terminal 150y. Block 410 performs spatial processing for transmitting data in a downlink for a beam-controlling method.

, для

. В пространственном RX процессоре 160y блок 456 выполняет скалярное произведение вектора

, для

, с подобранным вектором фильтра

. Результат скалярного произведения затем измеряется

блоком 458 для того, чтобы получить символ

, который является оценкой символа модуляции

. Блоки 456 и 458 выполняют пространственную обработку для согласованной фильтрации нисходящей линии связи для регулирующего луч способа.At user terminal 150y, downlink signals are processed by receive chain 454 in demodulator 154y in order to obtain a receive vector

for

. In the spatial RX processor 160y, block 456 performs the scalar product of the vector

for

, with a matched filter vector

. The result of the scalar product is then measured

block 458 in order to get the character

Which is an estimate of the modulation symbol

. Blocks 456 and 458 perform spatial processing for matched downlink filtering for the beam-controlling method.

, для

, сначала умножается с нормализованным собственным вектором

блоком 460 и затем дополнительно умножается с матрицей коррекции

блоком 462 для того, чтобы получить вектор передачи

. Вектор

, для

, затем обрабатывается цепью передачи 464 в модуляторе 154y и передается по каналу MIMO в точку доступа 110y. Блок 460 выполняет пространственную обработку для передачи данных по восходящей линии связи для регулирующего луч способа.For the uplink in the TX spatial processor 190y of the user terminal 150y, a modulation symbol

for

is first multiplied with the normalized eigenvector

block 460 and then further multiplied with a correction matrix

block 462 in order to obtain a transmission vector

. Vector

for

, then processed by the transmission chain 464 in the modulator 154y and transmitted on the MIMO channel to the access point 110y. Block 460 performs spatial processing for transmitting uplink data for the beam-steering method.

, для

. В пространственном RX процессоре 140y блок 426 выполняет скалярное произведение вектора приема

, для

, с подобранным вектором фильтра

. Результат скалярного произведения затем измеряется

блоком 428 для того, чтобы получить символ

, который является оценкой символа модуляции

. Блоки 426 и 428 выполняют пространственную обработку для согласованной фильтрации восходящей линии связи для регулирующего луч способа.At access point 110y, uplink signals are processed by receive chain 424 in demodulator 124y in order to obtain a receive vector

for

. In spatial RX processor 140y, block 426 performs the scalar product of the receive vector

for

, with a matched filter vector

. The result of the scalar product is then measured

block 428 in order to receive the character

Which is an estimate of the modulation symbol

. Blocks 426 and 428 perform spatial processing for matched uplink filtering for the beam-steering method.

4. Adjustable reference signal (adjustable link)

, для

, восходящей линии связи, в отсутствии помех, равен вектору данных

, преобразованному

, который является матрицей

левых собственных векторов

, измеренных диагональной матрицей

сингулярных значений. Как показано в уравнениях (17) и (18), из-за взаимного канала и калибровки, матрица

и ее перемещение используются для пространственной обработки передачи нисходящей линии связи и пространственной обработки (согласованной фильтрации) принятой передачи восходящей линии связи, соответственно.As shown in equation (15), at the access point, the received vector

for

, uplink, in the absence of interference, equal to the data vector

, transformed

which is a matrix

left eigenvectors

measured by a diagonal matrix

singular values. As shown in equations (17) and (18), due to the mutual channel and calibration, the matrix

and its movement is used for spatial processing of the downlink transmission and spatial processing (matched filtering) of the received uplink transmission, respectively.

и

, для

, не имея необходимость оценивать MIMO канал или выполнять сингулярную декомпозицию. Точно так же регулируемая ссылка может быть передана точкой доступа и использоваться терминалом пользователя для того, чтобы получить оценки и

и

.An adjustable link (or adjustable pilot) may be transmitted by the user terminal and used by the access point in order to obtain estimates and

and

for

Without having to evaluate the MIMO channel or perform the singular value decomposition. Similarly, a regulated link can be transmitted by an access point and used by a user terminal in order to obtain estimates and

and

.

An adjustable link contains a specific OFDM symbol (called a pilot or “P” OFDM symbol), which is transmitted from all antennas N _ut in the user terminal (for the uplink) or antennas N _ap in the access point (for the downlink). The P OFDM symbol is transmitted on only one wideband eigenmode, performing spatial processing with a set of eigenvectors for that broadband eigenmode.

A. Regulated Uplink Link

An uplink adjustable link transmitted by a user terminal may be expressed as:

, для

, Уравнение 31

for

, Equation 31

представляет собой вектор передачи для k-й подполосы m-й широкополосной собственной моды;Where

represents the transmission vector for the kth subband of the mth wideband eigenmode;

представляет собой собственный вектор для k-й подполосы m-й широкополосной собственной моды; и

represents an eigenvector for the kth subband of the mth broadband eigenmode; and

p (k) is the modulation symbol of the pilot signal that was transmitted on the k-th subband.

представляет собой m-ю колонку матрицы

_, где

.Eigenvector

represents the mth column of the matrix

_where

.

A received uplink adjustable link at an access point may be expressed as:

, для

, Уравнение 32

for

, Equation 32

представляет собой принятый вектор для регулируемой ссылки восходящей линии связи для k-й подполосы m-й широкополосной собственной моды; иWhere

represents an accepted vector for an uplink adjustable link for the kth subband of the mth wideband eigenmode; and

представляет собой сингулярное значение для k-й подполосы m-й широкополосной собственной моды.

represents the singular value for the kth subband of the mth wideband eigenmode.

Methods for evaluating a channel response based on a custom link are described in detail below.

B. Adjustable Downlink Link

A downlink adjustable link transmitted by an access point may be expressed as:

, для

, Уравнение 33,

for

, Equation 33 ,

представляет собой вектор передачи для k-й подполосы m-й широкополосной собственной моды; иWhere

represents the transmission vector for the kth subband of the mth wideband eigenmode; and

представляет собой собственный вектор для k-й подполосы m-й широкополосной собственной моды. Регулируемый вектор

представляет собой m-ю колонку матрицы

, где

.

is an eigenvector for the kth subband of the mth broadband eigenmode. Adjustable vector

represents the mth column of the matrix

where

.

A downlink adjustable link may be used by a user terminal for various purposes. For example, an adjustable downlink link allows the user terminal to determine which rating for the MIMO channel the access point has (since the access point has a channel rating estimate). A downlink adjustable link may also be used by a user terminal to evaluate a received downlink transmission SNR.

C. Adjustable link for beam adjustment

). Регулируемая ссылка, сгенерированная, используя набор нормализованных собственных векторов для всех подполос, затем может быть послана передатчиком и использована приемником для того, чтобы получить согласованные векторы фильтра для этих подполос для регулирующего луч способа.For the beam-regulating method, spatial processing on the transmission side is performed using a series of normalized eigenvectors for the main broadband eigenmode. The full transfer function with a normalized eigenvector is different from the full transfer function with a non-normalized eigenvector (i.e.,

) An adjustable link generated using a set of normalized eigenvectors for all subbands can then be sent by the transmitter and used by the receiver to obtain consistent filter vectors for these subbands for the beam-controlling method.

For an uplink channel, an adjustable link for a beam-steering method may be expressed as:

, для

Уравнение 34

for

Equation 34

At the access point, the adjustable uplink reception link for the beam-steering method may be expressed as:

, для

Уравнение 35

for

Equation 35

для передачи с регулированием луча восходящей линии связи, принятый вектор

для регулируемой ссылки сначала умножают с

. Затем результат объединяют по многократным принятым символам регулируемой ссылки для того, чтобы сформировать оценку

. Вектор

затем объединяет перемещение этой оценки.To get a consistent filter string vector

for uplink beam control transmission, received vector

for an adjustable reference, first multiply with

. Then, the result is combined over multiple received symbols of the adjustable link in order to form an estimate

. Vector

then combines the movement of this estimate.

, один или более символов, используя собственный вектор

для основной собственной моды, и возможно один или более символов, используя собственные векторы для другой собственной моды. Символы регулируемой ссылки, сгенерированные с

могут быть использованы точкой доступа для того, чтобы получить подобранный вектор фильтра

. Символы регулируемой ссылки, сгенерированные с

могут быть использованы для того, чтобы получить

, который может затем быть использован для того, чтобы получить нормализованный собственный вектор

, используемый для регулирования луча на нисходящей линии связи. Символы регулируемой ссылки, сгенерированные с собственными векторами

через

для других собственных мод, могут быть использованы точкой доступа для того, чтобы получить

через

и сингулярные значения для этих других собственных мод. Затем эта информация может быть использована точкой доступа для того, чтобы решить, использовать ли способ пространственного мультиплексирования или регулирующий луч способ для передачи данных.By operating in a beam-steering manner, a user terminal may transmit a plurality of adjustable link symbols, for example, one or more symbols, using a normalized eigenvector

one or more characters using an eigenvector

for the main eigenmode, and possibly one or more characters, using eigenvectors for another eigenmode. Custom Link Symbols Generated With

can be used by an access point in order to obtain a matched filter vector

. Custom Link Symbols Generated With

can be used in order to get

, which can then be used to obtain a normalized eigenvector

used to control the beam in the downlink. Custom Link Symbols Generated with Eigenvectors

across

for other own mods, can be used by an access point in order to get

across

and singular values for these other eigenmodes. This information can then be used by the access point to decide whether to use the spatial multiplexing method or the beam steering method for data transmission.

для регулирующего луч способа, основанный на калиброванной оценке ответа канала нисходящей линии связи

. В частности, терминал пользователя имеет

от сингулярной декомпозиции

и может получить нормализованный собственный вектор

. Терминал пользователя может затем умножить

с

для того, чтобы получить

, и может затем получить

, основанный на

. Альтернативно, регулируемую ссылку можно послать точкой доступа, используя нормализованный собственный вектор

, и эта регулируемая ссылка может быть обработана терминалом пользователя способом, описанным выше, чтобы получить

.For the downlink, the user terminal may receive a consistent filter vector

for a beam-steering method based on a calibrated downlink channel response estimate

. In particular, the user terminal has

from singular decomposition

and can get a normalized eigenvector

. User terminal can then multiply

from

in order to receive

, and can then get

, based on

. Alternatively, a custom link can be sent by an access point using a normalized eigenvector

, and this custom link can be processed by the user terminal in the manner described above to obtain

.

D. Custom Link Estimation

. Точка доступа может таким образом получить оценку ответа канала восходящей линии связи, основанную на регулируемой ссылке, посланной терминалом пользователя. Различные методы оценки могут быть использованы для того, чтобы получить оценку ответа канала.As shown in equation (32), at the access point, the received uplink adjustable link (in the absence of interference) is approximately

. An access point can thus obtain an uplink channel response estimate based on a controlled link sent by a user terminal. Various estimation methods can be used to obtain an estimate of the channel response.

, принятый вектор

, для регулируемой ссылки для m-ой широкополосной собственной моды, сначала умножают с комплексом, сопряженным из символа модуляции контрольного сигнала, p ^* (k), используемого для регулируемой ссылки. Результат затем объединяют по множеству принятым символам регулируемой ссылки для каждой широкополосной собственной моды для того, чтобы получить оценку

, которая измеряет левый собственный вектор

для m-й широкополосной собственной моды. Каждые из N _ap элементов

получены на основании соответствующего одного из N _ap элементов для

, где N _ap элементы

- принятые символы, полученные от антенн N _ap в точке доступа. Так как собственные векторы имеют единичную мощность, сингулярное значение

может быть оценено на основании полученной мощности регулируемой ссылки, которая может быть измерена для каждой подполосы каждой широкополосной собственной моды.In one embodiment, in order to obtain an estimate

, accepted vector

, for an adjustable link form-th broadband eigenmode, first multiplied with a complex conjugated from the modulation symbol of the control signal,p ^* (k) used for adjustable links. The result is then combined over the plurality of received adjustable link symbols for each broadband eigenmode in order to obtain an estimate

, which measures the left eigenvector

 form-th broadband own fashion. Each ofN _ap elements

 obtained on the basis of one ofN _ap elements for

whereN _ap the elements

 - received symbols received from antennasN _ap at the access point. Since the eigenvectors have unit power, the singular value

 can be estimated based on the received power of the adjustable link, which can be measured for each subband of each broadband eigenmode.

, основанную на принятом векторе

для регулируемой ссылки. Так как символы p(k) модуляции контрольного сигнала известны, точка доступа может получить оценку

так, как среднеквадратическая ошибка между принятыми символами контрольного сигнала (полученная после выполнения подобранного фильтрования на принятом векторе

) и переданными символами контрольного сигнала минимизирована. Использование метода MMSE для пространственной обработки в приемнике подробно описано в США заявке на патент № 09/993,087, названной "Multiple-Access Multiple-Input Multiple-Output (MIMO) Communication System", поданной 6 ноября 2001 г.In another embodiment, the minimum mean square error (MMSE) method is used to obtain an estimate

based on accepted vector

for an adjustable link. Since the pilot modulation symbols p (k) are known, the access point can obtain an estimate

as the standard error between the received symbols of the control signal (obtained after performing selected filtering on the received vector

) and transmitted pilot symbols are minimized. The use of the MMSE method for spatial processing at the receiver is described in detail in US Patent Application No. 09 / 993,087, entitled "Multiple-Access Multiple-Input Multiple-Output (MIMO) Communication System", filed November 6, 2001.

An adjustable link is sent for one broadband mode at any given symbol period, and can in turn be used to obtain an estimate of one eigenvector for each subband of that wideband eigenmode. Thus, the receiver is able to obtain an estimate of one eigenvector in the unitary matrix during any given symbol period. Since estimates of multiple eigenvectors for the unitary matrix were obtained for different periods of the symbol, and due to interference and other sources of deterioration in the transmission path, the estimated eigenvectors for the unitary matrix are unlikely to be orthogonal. If the estimated eigenvectors are subsequently used for spatial processing of data transmission on another communication line, then any errors in orthogonality in these estimated eigenvectors would lead to cross-coupling among the eigenmodes, which can degrade performance.

In an embodiment, the estimated eigenvectors for each unitary matrix are forced to be orthogonal to each other. Orthogonalization of eigenvectors can be achieved using the Gram-Schmidt technique, which is described in detail in the above link from Hilbert Strang, or some other method.

Other methods for evaluating a channel response based on a custom link may also be used, and this is within the scope of the invention.

и

основываясь на регулируемой ссылке, посланной терминалом пользователя, не имея необходимость оценивать ответ канала восходящей линии связи или выполнять сингулярную декомпозицию на

. Так как только N _ut широкополосных собственных мод имеют любую мощность, матрица

левых собственных векторов

является эффективной (N _ap × N _ut ), и матрица

может быть рассмотрена, чтобы быть (N _ut × N _ut)An access point can thus evaluate and

and

based on the adjustable link sent by the user terminal without having to evaluate the response of the uplink channel or perform a singular decomposition into

. Since only N _ut broadband eigenmodes have any power, the matrix

left eigenvectors

is effective (N _ap × N _ut ), and the matrix

may be considered to be ( N _ut × N _ut )

и

, для

, основанной на регулируемой ссылке нисходящей линии связи, может быть выполнена подобно регулируемой ссылке восходящей линии связи, описанной выше.Processing in user terminal for matrix evaluation

and

for

Based on an adjustable link downlink it may be performed similarly adjustable link uplink as described above.

5. Channel estimation and spatial processing

5 is a flowchart of a specific embodiment of a process 500 for performing channel estimation and spatial processing at an access point and user terminal, in accordance with one embodiment of the invention. The process 500 includes two parts — calibration (block 510) and normal operation (block 520).

и

, для

(в блоке 512). Калибровка должна быть выполнена лишь однажды (например, в начале сеанса связи, или в самый первый раз, когда терминал пользователя включают). Матрицы коррекции

и

впоследствии используются точкой доступа и терминалом пользователя, соответственно, на стороне передачи, как описано выше.Initially, the access point and user terminal perform calibration in order to determine the differences in the responses of their transmit and receive chains and obtain correction matrices

and

for

(in block 512). Calibration should be performed only once (for example, at the beginning of a communication session, or the very first time that a user terminal is turned on). Correction matrices

and

subsequently used by the access point and user terminal, respectively, on the transmission side, as described above.

During normal operation, the access point transmits a MIMO pilot to a calibrated downlink channel (at block 522). The user terminal receives and processes the MIMO pilot, estimates the response of the calibrated downlink channel based on the received MIMO pilot, and supports the estimation of the response of the calibrated downlink (in block 524). This shows that the characteristics are better (i.e., less degradation) when the channel response estimate is accurate. An accurate estimate of the channel response can be obtained by averaging the estimates obtained from the plurality of received MIMO pilot transmissions.

, для

, для того, чтобы получить диагональную матрицу

и унитарную матрицу

(в блоке 526). Матрица

содержит и левые собственные векторы

и

и правые собственные векторы

. Матрица

таким образом может быть использована терминалом пользователя для того, чтобы выполнить пространственную обработку для передачи данных, принятой на нисходящей линии связи так же, как для передачи данных, которая будет послана по восходящей линии связи.The user terminal then analyzes a calibrated downlink channel response estimate,

for

, in order to get the diagonal matrix

and unitary matrix

(at block 526). Matrix

contains left eigenvectors

and

and right eigenvectors

. Matrix

thus can be used by a user terminal to perform spatial processing for transmitting data received on the downlink as well as for transmitting data to be sent on the uplink.

, как показано в уравнении (31) (в блоке 530). Точка доступа принимает и обрабатывает регулируемую ссылку восходящей линии связи для того, чтобы получить диагональную матрицу

и унитарную матрицу

, для

(в блоке 532).The user terminal then transmits the adjustable link on the uplink to the access point using eigenvectors in the matrix

as shown in equation (31) (at block 530). The access point receives and processes an uplink adjustable link in order to obtain a diagonal matrix

and unitary matrix

for

(at block 532).

содержит и левые собственные векторы

и

и правые собственные векторы

. Матрица

может таким образом использоваться точкой доступа для того, чтобы выполнить пространственную обработку для передачи данных, принятой по восходящей линии связи так же, как для передачи данных, которая будет послана по нисходящей линии связи.Matrix

contains left eigenvectors

and

and right eigenvectors

. Matrix

can thus be used by the access point to perform spatial processing for transmitting data received on the uplink as well as for transmitting data to be sent on the downlink.

, для

, получена на основании оценки регулируемой ссылки восходящей линии связи, которая в свою очередь сгенерирована с собственным вектором, который получен на основании оценки ответа калиброванного канала нисходящей линии связи. Таким образом, матрица

эффективно оценивает оценку. Точка доступа может усреднить передачи регулируемой ссылки восходящей линии связи для того, чтобы получить более точную оценку фактической матрицы

.Matrix

for

, obtained on the basis of the estimated adjustable link uplink, which in turn is generated with an eigenvector, which is obtained on the basis of the estimated response of the calibrated channel downlink. So the matrix

effectively evaluates the score. An access point can average the transmission of a regulated uplink link in order to obtain a more accurate estimate of the actual matrix

.

и

, соответственно, передача данных может начаться на нисходящей линии связи и/или восходящей линии связи. Для передачи данных нисходящей линии связи точка доступа выполняет пространственную обработку на символах с матрицей

правых собственных векторов

и передает на терминал пользователя (в блоке 540). Терминал пользователя затем получает и пространственно обрабатывает передачу данных нисходящей линии связи с матрицей

, которая является объединенным перемещением матрицы

левых собственных векторов

(в блоке 542). Для передачи данных восходящей линии связи, терминал пользователя выполняет пространственную обработку на символах с матрицей

правых собственных векторов

, и передает в точку доступа (в блоке 550). Точка доступа получает и пространственно обрабатывает передачу данных восходящей линии связи с матрицей

, которая является объединенной с перемещением матрицы

левых собственных векторов

(в блоке 552).Once the user terminal and access point receive matrices

and

accordingly, data transmission may begin on the downlink and / or uplink. To transmit downlink data, the access point performs spatial processing on matrix symbols

right eigenvectors

and transmits to the user terminal (at block 540). The user terminal then receives and spatially processes the downlink data transmission with the matrix

which is the combined displacement of the matrix

left eigenvectors

(at block 542). For uplink data transmission, the user terminal performs spatial processing on matrix symbols

right eigenvectors

, and transmits to the access point (in block 550). The access point receives and spatially processes the uplink data transmission with the matrix

which is combined with the displacement of the matrix

left eigenvectors

(at block 552).

Data transmission on the downlink and / or uplink may continue until it is terminated by the access point or user terminal. While the user terminal is inactive (i.e., has no data to receive and transmit), the MIMO pilot and / or adjustable link can still be sent in order to allow the access point and user terminal to maintain the most recent downstream channel response estimates link and uplink channel, respectively. Then it will allow data transfer to start quickly, even when resuming.

For clarity, channel estimation and spatial processing techniques have been described for a specific embodiment in which a user terminal estimates the response of a calibrated downlink channel based on the MIMO pilot of the downlink channel and performs a singular decomposition. Channel estimation and singular decomposition can also be performed by an access point, and this is within the scope of the invention. In general, due to the mutual channel for a TDD system, channel estimation should only be performed at one end of the communication.

The methods described here can be used with or without calibration. Calibration can be performed in order to improve channel estimates, which can then improve system performance.

The methods described here can also be used in conjunction with other spatial processing methods, such as water-filling to distribute transmit power among wideband eigenmodes, and channel inversion for distributing transmit power among subbands of each broadband eigenmode. Channel inversion and water-filling are described in the aforementioned US Patent Application No. 60 / 421,309.

Channel estimation and spatial processing techniques described herein may be implemented by various means. For example, these methods may be implemented in hardware, software, or a combination thereof. For execution in hardware, elements used to implement the methods described here can be implemented within one or more specialized integrated circuits (ASICs), digital signal processors (DSP), digital signal processing devices (DSPD), programmable logic devices (PLD) , programmable logic element arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, other electronic units designed to perform the functions described here, or a combination thereof .

For execution in software, channel estimation and spatial processing techniques may be implemented with modules (eg, procedures, functions, and so on) that perform the functions described herein. Software codes may be stored in a memory unit (e.g., memory unit 132 and 182 in FIG. 1) and executed by a processor (e.g., controllers 130 and 180). The memory unit can be used in the processor or outside it, in some cases it can be combined with the processor through various means, as is known in the art.

Headings are included here for reference and assistance in locating specific sections. These headings are not intended to limit the scope of the concepts described there, and these concepts may have applicability in other sections throughout the specification.

The previous 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 basic principles defined herein can 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 by the embodiments shown here, but should receive the broadest possible possibilities consistent with the principles and new features disclosed herein.

Claims (60)

1. A method of performing spatial processing in a wireless time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), which is that
processing a first transmission signal received through the first communication line to obtain at least one eigenvector used for spatial processing and to transmit data received through the first communication line and to transmit data sent via the second communication line; and
perform spatial processing for the second transmission signal, with at least one eigenvector prior to transmission on the second communication line. 2. The method according to claim 1, in which additionally
performing spatial processing on a third gear signal received via a first communication link with at least one eigenvector for reconstructing data symbols for a third gear signal. 3. The method according to claim 1, in which the first transmission signal is an adjustable pilot signal received on at least one eigenmode of the MIMO channel for the first communication line. 4. The method of claim 1, wherein the first transmission signal is a MIMO pilot signal comprising a plurality of pilot transmissions transmitted from a plurality of transmit antennas and wherein the pilot transmission from each transmit antenna is an identifiable MIMO pilot receiver . 5. The method according to claim 4, in which the processing of the first transmission signal includes the steps of
obtaining a channel response estimate for the first communication link based on the MIMO pilot, and
carry out decomposition of the channel response estimate to obtain a plurality of eigenvectors used for spatial processing for the first and second communication lines. 6. The method according to claim 5, in which the decomposition of the channel response estimates for the first communication line is carried out using the decomposition of singular values. 7. The method according to claim 4, in which additionally
performing spatial processing on the pilot symbols with at least one eigenvector to generate an adjustable pilot signal for transmission on the at least one eigenmode of the MIMO channel for the second communication line. 8. The method according to claim 1, in which the second transmission signal is spatially processed with one eigenvector for transmission on one eigenmode of the MIMO channel for the second communication line. 9. The method according to claim 1, in which the second transmission signal is spatially processed with a normalized eigenvector for transmission on one eigenmode of the MIMO channel for the second communication line, wherein the normalized eigenvector includes many elements having the same magnitude. 10. The method according to claim 1, in which the first transmission signal is an adjustable pilot signal generated using the normalized eigenvector for one eigenmode of the MIMO channel for the first communication line, wherein the normalized eigenvector includes many elements having the same value, and thus receive one eigenvector used for spatial processing for the first and second communication lines. 11. The method according to claim 1, in which additionally
calibrate the first and second communication lines so that the channel response estimate for the first communication line is a mutual channel response estimate for the second communication line. 12. The method according to claim 11, in which the calibration includes steps in which
receive correction factors for the first communication line based on the channel response estimates for the first and second communication lines, and
receive correction factors for the second communication line based on the channel response estimates for the first and second communication lines. 13. The method according to claim 1, in which the TDD MIMO communication system uses orthogonal frequency division multiplexing (OFDM), and wherein the processing for the first transmission signal and the spatial processing for the second transmission signal are performed for each of a plurality of subbands. 14. A device for spatial processing in a wireless time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), comprising
means for processing the first transmission signal received through the first communication line to obtain at least one eigenvector used for spatial processing and to transmit data received through the first communication line and to transmit data sent through the second communication line; and
means for performing spatial processing for the second transmission signal with at least one eigenvector prior to transmission on the second communication line. 15. The device according to 14, additionally containing
means for performing spatial processing on the third gear signal received through the first communication line with at least one eigenvector for reconstructing data symbols for the third gear signal. 16. The device according to 14, in which the first transmission signal is an adjustable pilot signal received on at least one eigenmode of the MIMO channel for the first communication line. 17. The apparatus of claim 14, wherein the first transmission signal is a MIMO pilot signal consisting of a plurality of pilot transmissions sent from a plurality of transmitting antennas, and wherein the transmission of the pilot signal from each transmitting antenna is identifiable by the pilot MIMO signal. 18. The device according to 17, additionally containing
means for obtaining a channel response estimate for a first communication link based on a MIMO pilot; and
means for decomposing the channel response estimate to obtain a plurality of eigenvectors used for spatial processing for the first and second communication lines. 19. A device for spatial processing in a wireless time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), comprising
a controller configured to process the first transmission signal received through the first communication line to obtain at least one eigenvector used for spatial processing and to transmit data received through the first communication line and to transmit data sent through the second communication line ; and
a spatial transmission processor configured to perform spatial processing for the second transmission signal with at least one eigenvector prior to transmission on the second communication line. 20. The device according to claim 19, further comprising
a spatial receive processor configured to perform spatial processing on a third gear signal received via a first communication link with at least one eigenvector for reconstructing data symbols for a third gear signal. 21. The device according to claim 19, in which the first transmission signal is an adjustable pilot signal received on at least one eigenmode of the MIMO channel for the first communication line. 22. The device according to claim 19, in which the first transmission signal is a MIMO pilot signal consisting of a plurality of pilot transmissions sent from a plurality of transmitting antennas, and wherein the transmission of the pilot signal from each transmitting antenna is identified by the pilot receiver MIMO signal. 23. The device according to item 22, in which the controller is additionally configured to obtain a channel response estimate for the first communication line, based on the MIMO pilot and decomposition of the channel response estimate to obtain a plurality of eigenvectors used for spatial processing for the first and second lines communication. 24. A method of performing spatial processing in a wireless time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), namely, that
processing the MIMO pilot received through the first communication line to obtain a plurality of eigenvectors used for spatial processing and for transmitting data received through the first communication line and for transmitting data sent through the second communication line, the MIMO pilot containing a plurality pilot transmissions sent from a plurality of transmit antennas, and wherein the pilot transmission from each transmit antenna is an identifiable MIMO pilot receiver;
performing spatial processing on a first data transmission received via a first communication line with a plurality of eigenvectors for recovering data symbols for a first data transmission; and
perform spatial processing for the second data transmission with many eigenvectors before transmission on the second communication line. 25. The method according to paragraph 24, in which additionally perform spatial processing on the symbols of the pilot signal with at least one of the eigenvectors for generating an adjustable pilot signal for transmission on at least one eigenmode of the MIMO channel for the second communication lines. 26. The method according to paragraph 24, in which additionally
perform calibration to obtain correction factors; and
scale the second data transmission with correction factors before transmission on the second communication line. 27. The method according to paragraph 24, in which the TDD MIMO communication system uses orthogonal frequency division multiplexing (OFDM), and the spatial processing is performed for each set of subbands. 28. A device for spatial processing in a wireless time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), comprising
means for processing the MIMO pilot received through the first communication line to obtain a plurality of eigenvectors used for spatial processing and for transmitting data received through the first communication line and for transmitting data sent through the second communication line, the MIMO pilot comprises a plurality of pilot transmissions sent from a plurality of transmit antennas, and wherein the pilot transmission from each transmit antenna is an identifiable MIMO pilot receiver;
means for performing spatial processing on a first data transmission received via a first communication line with a plurality of eigenvectors for reconstructing data symbols for a first data transmission; and
means for performing spatial processing for a second data transmission with multiple eigenvectors prior to transmission on the second communication line. 29. The device according to p, optionally containing
means for performing spatial processing on the pilot symbols with at least one of the eigenvectors for generating an adjustable pilot signal for transmission on the at least one eigenmode of the MIMO channel for the second communication line. 30. The device according to p, optionally containing
means for performing calibration to obtain correction factors; and
means for scaling the second data transmission with correction factors before transmission on the second communication line. 31. A device for spatial processing in a wireless time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), comprising
a controller configured to process the MIMO pilot received through the first communication line to obtain a plurality of eigenvectors used for spatial processing and to transmit data received through the first communication line and to transmit data sent through the second communication line, the pilot the MIMO signal comprises a plurality of pilot transmissions sent from a plurality of transmit antennas, and wherein the transmission of a pilot signal from each transmit antenna is an identifiable MIMO pilot receiver;
a spatial receive processor configured to perform spatial processing on a first data transmission received via a first communication line with a plurality of eigenvectors for reconstructing data symbols for a first data transmission; and
a spatial transmission processor configured to perform spatial processing for a second data transmission with a plurality of eigenvectors prior to transmission on the second communication line. 32. The device according to p, in which the spatial transmission processor is additionally configured to perform spatial processing on the symbols of the pilot signal with at least one of the eigenvectors for generating an adjustable pilot signal for transmission on at least one native mode MIMO channel for the second communication line. 33. The device according to p, in which the controller is additionally configured to perform calibration to obtain correction factors, and the spatial transmission processor is further configured to scale the second data transmission with correction factors before transmission on the second communication line. 34. A method of performing spatial processing in a wireless time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), which is that
process an adjustable pilot signal received through at least one eigenmode of the MIMO channel for the first communication line to obtain at least one eigenvector used for spatial processing and for transmitting data received through the first communication line and for transmitting data sent through a second communication line;
performing spatial processing on a first data transmission received via a first communication line with at least one eigenvector; and
perform spatial processing for a second data transmission with at least one eigenvector prior to transmission on the second communication line. 35. The method according to clause 34, in which additionally generate a MIMO pilot signal for transmission on the second communication line, and the MIMO pilot signal contains many pilot transmissions sent from multiple transmit antennas, and the transmission of the pilot signal from each The transmit antenna is an identifiable MIMO pilot receiver. 36. A device for spatial processing in a wireless time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), comprising
means for processing the adjustable pilot signal received through at least one eigenmode of the MIMO channel for the first communication line, to obtain at least one eigenvector used for spatial processing and for transmitting data received through the first communication line and for transmitting data sent through a second communication line;
means for performing spatial processing on a first data transmission received via a first communication line with at least one eigenvector; and
means for performing spatial processing for the second data transmission with at least one eigenvector prior to transmission on the second communication line. 37. The device according to clause 36, further comprising
means for generating a MIMO pilot for transmission on a second communication line, wherein the MIMO pilot comprises a plurality of pilot transmissions sent from a plurality of transmit antennas, and wherein the transmission of a pilot signal from each transmit antenna is an identifiable MIMO pilot receiver . 38. A device for spatial processing in a wireless time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), comprising
a controller configured to process the adjustable pilot received through at least one eigenmode of the MIMO channel for the first communication line to obtain at least one eigenvector used for spatial processing and data transmission received through the first line communication, and data transmission sent through a second communication line;
a spatial receiving processor, configured to perform spatial processing on a first data transmission received via a first communication line with at least one eigenvector; and
a spatial transmission processor configured to perform spatial processing for a second data transmission with at least one eigenvector prior to transmission on the second communication line. 39. The device according to § 38, in which the spatial transmission processor is further configured to generate a MIMO pilot for transmission on a second communication line, the MIMO pilot signal comprising a plurality of pilot transmissions sent from a plurality of transmit antennas, and pilot transmission from each transmit antenna is an identifiable MIMO pilot receiver. 40. A method of performing spatial processing in a wireless time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), which is that
performing spatial processing on the pilot symbols with a normalized eigenvector for one eigenmode of the MIMO channel to generate a first adjustable pilot signal for transmission through one eigenmode of the MIMO channel, wherein the normalized eigenvector contains many elements having the same value; and
perform spatial processing on data symbols with a normalized eigenvector before transmission on one eigenmode of the MIMO channel. 41. The method according to p, in which additionally:
performing spatial processing on pilot symbols with a non-normalized eigenvector for one eigenmode to generate a second adjustable pilot signal for transmission through one eigenmode of the MIMO channel. 42. A method of performing spatial processing in a wireless time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO) with orthogonal frequency division multiplexing (OFDM), the method comprising:
they process the first transmission signal received through the first communication line to obtain an eigenvector matrix for each of a plurality of subbands, wherein a plurality of eigenvector matrices are obtained for a plurality of subbands and used for spatial processing and for transmitting data received through the first communication line and transmitting data sent through second line of communication; and
perform spatial processing for the second transmission signal with many matrices of eigenvectors before transmission on the second communication line. 43. The method according to § 42, in which additionally
arrange the eigenvectors in each matrix based on the transmission coefficients of the channel associated with the eigenvectors. 44. The method of claim 43, wherein the second transmission signal is sent to at least one wideband eigenmode, each wideband eigenmode associated with a set of eigenvectors in a plurality of matrices having the same order after ordering. 45. A method for estimating a wireless channel in a time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), the method comprising:
processing the transmission of the pilot signal received through the first communication line to obtain an estimate of the channel response for the first communication line; and
carry out decomposition of the channel response estimate to obtain a matrix of eigenvectors used for spatial processing and for transmitting data received through the first communication line and for transmitting data sent through the second communication line. 46. A method for estimating a wireless channel in a time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), the method comprising:
receiving an adjustable pilot on at least one eigenmode of the MIMO channel for the first communication line; and
process the received adjustable pilot signal to obtain at least one eigenvector used for spatial processing and for transmitting data received through the first communication line and for transmitting data sent through the second communication line. 47. The method according to item 46, in which the processing includes the steps of
demodulating the received adjustable pilot signal to remove modulation from the pilot symbols used to generate the adjustable pilot signal, and
process a demodulated adjustable pilot signal to obtain at least one eigenvector. 48. The method according to item 46, in which at least one eigenvector is obtained on the basis of the method of minimum mean square error (MMSE). 49. The method according to item 46, in which receive a lot of eigenvectors, and they must be orthogonal to each other. 50. A method of performing data processing in a wireless communication system including an access point and a user terminal, the method comprising:
calibrating one or more communication lines, including a first communication line and a second communication line, between the access point and the user terminal to form a calibrated first communication line and a calibrated second communication line;
obtaining a channel response estimate for the calibrated first communication line based on one or more pilot signals transmitted on the calibrated first communication line; and
carry out decomposition of the channel response estimate to obtain one or more eigenvectors used for spatial processing of one or more communication lines. 51. The method of claim 50, wherein the calibration comprises the steps of determining one or more sets of correction factors based on channel response estimates for one or more communication lines; and
apply one or more sets of correction factors to the first and second communication lines to form a calibrated first and second communication lines. 52. The method according to item 50, in which additionally
perform spatial processing for data transmission on the first and second communication lines using one or more eigenvectors obtained from the decomposition of the channel response estimates for the calibrated first communication line. 53. The method according to paragraph 52, in which the implementation of the spatial processing includes a stage in which
transmit an adjustable reference signal on the second communication line using one or more eigenvectors. 54. The method according to item 53, in which additionally
performing spatial processing of one or more pilot symbols with one or more eigenvectors to generate an adjustable reference signal. 55. An apparatus for performing data processing in a wireless communication system including an access point and a user terminal, comprising
means for calibrating one or more communication lines, including a first communication line and a second communication line, between the access point and the user terminal to form a calibrated first communication line and a calibrated second communication line;
means for obtaining a channel response estimate for the calibrated first communication line based on one or more pilot signals transmitted on the calibrated first communication line; and
means for decomposing the channel response estimate to obtain one or more eigenvectors used for spatial processing of one or more communication lines. 56. The device according to clause 55, in which the means for calibration comprises means for determining one or more sets of correction factors based on estimates of channel responses for one or more communication lines; and
means for applying one or more sets of correction factors to the first and second communication lines to form a calibrated first and second communication lines. 57. The device according to item 55, further containing
means for performing spatial processing for transmitting data on the first and second communication lines using one or more eigenvectors obtained from decomposing the channel response estimate for the calibrated first communication line. 58. The device according to clause 57, in which the means for performing spatial processing contains
means for transmitting an adjustable reference signal on a second communication line using one or more eigenvectors. 59. The device according to § 58, further comprising
means for performing spatial processing of one or more pilot symbols with one or more eigenvectors to generate an adjustable reference signal. 60. A computer-readable storage medium encoded by instructions for performing spatial processing by a processor in a wireless time division duplex (TDD) system with multiple inputs and multiple outputs (MIMO), the instructions comprising a code for processing a first transmission received via a first communication line for obtain at least one eigenvector used for spatial processing and for modulated symbols received through the first communication line, and for modulated symbols sent through without a second communication line; and performing spatial processing for the second transmission with at least one eigenvector before transmission on the second communication line.

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