WO2013075320A1

WO2013075320A1 - Space division multiplexing receiver and air interface signal processing method

Info

Publication number: WO2013075320A1
Application number: PCT/CN2011/082902
Authority: WO
Inventors: 龚明
Original assignee: 中兴通讯股份有限公司
Priority date: 2011-11-24
Filing date: 2011-11-24
Publication date: 2013-05-30

Abstract

Disclosed is a space division multiplexing receiver, comprising a control decision module, a Minimum Mean Square Error (MMSE) module, a sphere decoding module, and a decoding module. The control decision module decides that the MMSE module or the sphere decoding module processes a received signal and notifies the corresponding module. The MMSE module and the sphere decoding module are configured to process the received signal after receiving a processing notification of the control decision module. The decoding module decodes data processed by the MMSE module or the sphere decoding module. Further disclosed is an air interface signal processing method. By means of the present invention, a signal can be received in an MMSE manner or a sphere decoding manner according to an actual condition, thereby having higher receiver performance and reducing the complexity.

Description

Space division multiplexing receiver and air interface signal processing method

The present invention relates to wireless communication technologies, and in particular, to a space division multiplexing receiver and an air interface signal processing method. Background technique

In the LTE communication system, in order to improve system throughput and improve link reliability, the system introduces multiple multi-antenna technologies, such as space-frequency coding and space division multiplexing, as well as multi-users similar to space division multiple access. Antenna technology.

For system downlink, the space division multiplexing technology enables spatial multiplexing of time-frequency resources in a cell, that is, each time-frequency resource block, multiple codewords are simultaneously transmitted on multiple antennas, and the receiver is also equipped with multiple The antenna is processed by Multiple Input Multiple Output (MIMO) technology to recover information of multiple codewords. The space division multiplexing technology helps the system to achieve a significant increase in capacity and becomes a mandatory technology for LTE. The User Equipment (UE) must support the reception of the space division multiplexing mode.

The structures of the general-purpose space division multiplex transmitter and the space division multiplex receiver are shown in Fig. 1 and Fig. 2, respectively. In the middle of the transceiver is a MIMO channel, which can be modeled by matrix H. Suppose there are N transmit antennas, M receive antennas, and the channel is a frequency flat fading channel. The received signal model is:

r - H _c s + n

Where y is the reception vector of Ν χ 1, s is the transmission signal vector of Μ χ 1, the average power is 1.0, n is the reception noise vector of Ν χ 1, and the noise power of each dimension is N. , H _c is the channel transmission matrix of NM. For normal LTE, it needs to support downlink 100Mbps reception, support 2 x 2 antenna configuration, spatial multiplexing number is 2, and two codewords are transmitted simultaneously. When M=N=2, the received signal model is:

A linear method can be used to solve the above problem. A more practical one is the Minimum Mean Square Error Error (MMSE) method. The pick-up adopts the structure of the line '1' raw equalizer. The linear equalizer not only considers the space. The suppression of each channel interference also takes into account the improvement of the useful signal, while suppressing the noise level as much as possible. The equalizer model is:

^X _MMSE- G _MMSE y

Wherein, the linear equalization matrix is ^^^^ + /)- ¹ ^^ , where H is a channel transmission matrix estimation value, which may also be referred to as a channel estimation value, and is provided by a channel estimation module.

After the equalization is performed, the two channels of parallel data can be processed independently. In order to improve the performance of the space division multiplexing receiver, the UE can also adopt a nonlinear method such as sphere decoding. The receiver using the sphere decoding method is actually a simplified form of the maximum likelihood receiver. Sphere decoding is limited by a variety of criteria to solve the problem of solving the European minimum distance in a subspace. The process is generally complicated. For a 2 x 2 system, the process is relatively simplified.

QR decomposition of the H matrix (channel estimate H is provided by the channel estimation module)

(1) Multiply both sides by the conjugate of Q to get

For equation (2), the sphere decoding method enumerates the possible combinations of transmitted signals and searches for the group that best matches the received signal, namely:

= arg minllzj - R _nSl

- ? ₀₀ - ² } ( 3 ) where C _M is a constellation set of 80 and ₈₁ . The above formula (2) undergoes QR decomposition, so that the total Euclidean distance in (3) is divided into two sum terms, the first term is only related to Si, and the spherical decoding method can enumerate _Sl first, for the determined _Sl , You can quickly search for the right s. Make the second item the smallest; traverse all the Si, and finally you can find the best combination, namely (3) in ^), ^.

The above process will perform traversal search on the signal constellation space of s _Q and Si. The preferred result of this method is the same as the maximum likelihood method, and the performance is good. In some channel environments, the throughput rate is 5~50% higher than the MMSE method. . However, the method is highly complex. For each MIMO problem, QR decomposition is required, and the signal constellation is also traversed. For example, in the 64QAM debugging mode, Si is searched 64 times for s. It is also necessary to perform multiple searches. If the spherical method needs to output soft bits, the complexity will increase several times. The experimental analysis shows that the power consumption of the sphere decoding reception can reach 10 times of the MMSE receiving power consumption.

It can be seen that although the MMSE receiver and the sphere decoding receiver are both optional when designing the LTE space division multiplexing receiver, the performance (error rate) of the MMSE receiver is inferior to the sphere decoding receiver in terms of performance. Correspondingly, the sphere decoding receiver can obtain higher throughput rate; in terms of complexity, the sphere decoding receiver is much more complicated, and the UE generates a lot of power when it works. It has not been proposed yet to have both high receiver performance and low complexity. Summary of the invention

In view of this, the main object of the present invention is to provide a space division multiplexing receiver and an air interface signal processing method, which have higher receiver performance and lower complexity.

In order to achieve the above object, the technical solution of the present invention is achieved as follows:

A space division multiplexing receiver, the LTE space division multiplexing receiver includes: a control decision module, a minimum mean square error estimation MMSE module, a sphere decoding module, and a decoding module; wherein the control decision module is configured to perform control decision, and the MMSE module or the sphere decoding module processes the received signal, and notifies the corresponding Module

The MMSE module is configured to process the received signal after receiving the processing notification of the control decision module;

The ball decoding module is configured to process the received signal after receiving the processing notification of the control decision module;

The decoding module is configured to decode data processed by the MMSE module or the sphere decoding module.

The LTE spatial division multiplexing receiver further includes a front end module and a channel estimation module; wherein the front end module is configured to receive an air interface signal, and process the air interface signal to obtain a frequency domain signal, for the MMSE module or the sphere translation Code module for processing;

The channel estimation module is configured to extract a reference symbol in the frequency domain signal, perform channel estimation, and obtain a channel estimation value H(i, j) on each subcarrier, where the control decision module performs a decision, where

H(i,j) = ' is 2 x 2 on the i-th subcarrier of the jth OFDM symbol

Channel coefficient moment. The control decision module performs control

The decision is:

Determining a first threshold, E(i, j) is greater than the first threshold, and determining to receive the ith subcarrier of the jth OFDM symbol by using an MMSE module; otherwise, the decision is to use a spherical decoding module for the jth OFDM The ith subcarrier of the symbol is received; or,

Presetting the second threshold and the third threshold, assuming that the number of all subcarriers in the i-th subframe is N, and calculating the number of subcarriers M that satisfy E(i, j) is greater than the second threshold; when M/N is greater than When the third threshold is used, the decision is to use the MMSE module to receive all the subcarrier data of the subframe. Otherwise, the decision is to use the ball decoding module to receive all the subcarrier data of the subframe.

The E(i, j) is greater than the first threshold or the second threshold is further reduced to A(i,j) > w x

B(i,j)c,

B(i, j) = ,

C (j, j) =

F{i, j) =| a(i, j) I ² + 1 b(i, j) I ² , G(i, j) =| c(i, j) | ² + 1 d(i, j ² ) The control decision module performs control decisions as:

Setting a fourth threshold t, the fourth threshold is greater than 1, when F(i, j) > tx G(i,j) or G(i, j) > tx F(i,j), the decision is to use sphere decoding The module receives the ith subcarrier of the jth OFDM symbol; otherwise, the decision is to use the MMSE module to receive the ith subcarrier of the jth OFDM symbol; or

The fifth threshold value 0 and the sixth threshold value V are set in advance, assuming that the number of all subcarriers in the i-th subframe is N, and the calculation statistics satisfy F(i, j) > ο χ G(i, j) or G(i, j > o χ F(i,j) number of subcarriers M,; When M, /N, < v, the decision is to use the MMSE module to receive all subcarrier data of the sub-frame; otherwise, the decision is spherical translation The code module receives all of the subcarrier data for the subframe.

G(i, j) =| c(i, j) I ² + 1 d(i, j) I ² , the control decision module performs the control decision as:

Presetting a seventh threshold t, and an eighth threshold, t, >l, when F(i, j) > t, X G(i,j) , or

G(i, j) > fx F(i,j), or E(i, j) is less than the eighth threshold, and the decision is to use the spherical decoding module to receive the ith subcarrier of the jth OFDM symbol; otherwise The decision is to use the MMSE module to receive the ith subcarrier of the jth OFDM symbol, or

The ninth threshold o, the tenth threshold V, and the eleventh threshold are set in advance, assuming that the number of all subcarriers in the i-th subframe is N", and the calculation statistic satisfies F(i, j) > ο χ G(i,j ) , or G(i, j) > ο χ F(i,j), or E(i,j) is less than the first threshold number of subcarriers M"; when M, VN"< v, the decision is to use the MMSE module for all subcarriers of the subframe The data is received. Otherwise, the decision uses the sphere decoding module to receive all subcarrier data of the subframe.

The control decision module performs a control decision as: extracting a portion of the E (i, j) pair to control.

The control decision module is further configured to adjust the threshold according to actual conditions.

The decision information of the subframe is used for the reception method selection of the subframe, and/or the reception method of the subframe after the subframe is selected.

An air interface signal processing method includes:

Control decision is made, and the frequency domain signal of the air interface signal is processed by the MMSE method or the sphere decoding method;

According to the decision result, the received frequency domain signal is processed according to the MMSE mode or the sphere decoding mode;

The data processed in accordance with the MMSE mode or the sphere decoding mode is decoded.

Before the controlling decision is made, the method further includes:

Receiving an air interface signal, and processing the air interface signal to obtain a frequency domain signal; extracting reference symbols in the frequency domain signal, performing channel estimation, and obtaining channel estimation values H i, j) on each subcarrier, where

H(i,j) = , which is 2 x 2 on the i-th subcarrier of the jth OFDM symbol

Channel coefficient matrix,

The control is performed as follows: A decision is made according to the H(i, j). , the control decision is as follows:

Presetting a first threshold, E(i, j) is greater than the first threshold, and determining, by using an MMSE module, to receive an ith subcarrier of the jth OFDM symbol; otherwise, the decision uses a spherical decoding mode The block receives the i-th subcarrier of the jth OFDM symbol; or

Presetting the second threshold and the third threshold, assuming that the number of all subcarriers in the i-th subframe is N, and calculating the number of subcarriers M satisfying E (i, j) greater than the second threshold; when M/N is greater than When the third threshold is used, the decision is to use the MMSE module to receive all the subcarrier data of the subframe. Otherwise, the decision is to use the ball decoding module to receive all the subcarrier data of the subframe.

The E(i, j) is greater than the first threshold or the second threshold is further simplified to A(i,j) > wx

B(i,j)c,

B(i, j) = , C ( , j) =

F{i,j) =| a(i,j) I ² + 1 b(i,j) I ² , G(i,j) =| c(i,j) | ² + 1 d(i,j ) ² , the control decision is as follows:

Setting a fourth threshold t, the fourth threshold is greater than 1, when F(i, j)>tx G(i,j) or G(i, j) > tx F(i,j), the decision is to use sphere decoding The module receives the ith subcarrier of the jth OFDM symbol; otherwise, the decision is to use the MMSE module to receive the ith subcarrier of the jth OFDM symbol; or

The fifth threshold value 0 and the sixth threshold value V are set in advance, assuming that the number of all subcarriers in the i-th subframe is N, and the calculation statistics satisfy F(i, j) > οχ G(i, j) or G(i, j) >οχ F(i,j) number of subcarriers M,; When M, /N, < v, the decision uses the MMSE module to receive all subcarrier data of the subframe; otherwise, the decision uses a spherical decoding module All subcarrier data of the subframe is received.

Oh, . . ,

^Ε ' ,

G(iJ) =| c(i,j) I ² + 1 d(i,j) I ² , the control decision is:

Setting a seventh threshold t, and an eighth threshold, t, >l, when F(i, j) > t, XG(i,j), or G(i, j) > fx F(i,j), Or E(i, j) is smaller than the eighth threshold, and the decision is to use the ball decoding module to receive the ith subcarrier of the jth OFDM symbol; otherwise, the decision adopts the MMSE mode. The block receives the i-th subcarrier of the jth OFDM symbol, or

The ninth threshold o, the tenth threshold V, and the eleventh threshold are set in advance, assuming that the number of all subcarriers in the i-th subframe is N", and the calculation statistic satisfies F(i, j) > ο χ G(i,j ), or G(i, j) > ο χ F(i,j) , or E(i, j) is less than the first threshold number of subcarriers M"; when M, VN" < v, The decision uses the MMSE module to receive all the subcarrier data of the subframe. Otherwise, the decision uses the sphere decoding module to receive all the subcarrier data of the subframe.

The control decision is made as follows: The extraction part E ( i, j ) pairs are subjected to control decisions.

The method further includes: adjusting the threshold according to actual conditions.

The space division multiplexing receiver and the air interface signal processing method of the present invention, the control decision module determines that the received signal is processed by the MMSE module or the sphere decoding module, and notifies the corresponding module; the MMSE module and the sphere decoding module are used for receiving After the processing notification by the control decision module, the received signal is processed; the decoding module decodes the processed data of the MMSE module or the sphere decoding module. According to the present invention, signal reception can be performed by using the MMSE method or the sphere decoding method according to actual conditions, so that the complexity can be reduced while having high receiver performance. DRAWINGS

1 is a schematic structural diagram of a universal space division multiplexing transmitter;

2 is a schematic structural diagram of a universal space division multiplexing receiver;

3 is a schematic structural diagram of a space division multiplexing receiver according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of another space division multiplexing receiver according to an embodiment of the present invention. detailed description

The basic idea of the present invention is: The decision of the control decision module is processed by the MMSE module or the sphere decoding module to process the received signal, and the corresponding module is notified; the MMSE module and the sphere decoding module, The method is configured to process the received signal after receiving the processing notification of the control decision module; and the decoding module decodes the processed data of the MMSE module or the sphere decoding module.

In order to obtain a suitable compromise between performance and complexity, the present invention introduces a complexity adaptive spatial division multiplex receiver. Generally, LTE has multi-user interference. Sometimes, although there is only one data stream to the UE, the UE can still use the MMSE receiver. At this time, the MMSE will suppress the neighboring area interference or the user interference of the cell, and the MMSE equalization. After that, the UE only needs to perform demodulation and decoding of its own data according to the debug coding information obtained by the UE. In this scenario, the sphere decoding method cannot be used because the receiver does not know how the interference data is modulated. Therefore, the MMSE receiver becomes an important option for the UE. In order to further improve the demodulation performance, the UE can also introduce a spherical decoding receiver module, and under certain conditions, the receiving module can be activated to obtain better performance.

Through the link simulation analysis under different channel models, it is found that when the channel spatial correlation is small (or uncorrelated), the performance difference between the performance of the MMSE receiver and the spherical decoding receiver is small. Ideally, the performance of the two is better. The difference is almost the same; when the spatial channel correlation is relatively large, the performance of the spherical decoding receiver is obviously better than that of the MMSE receiver. The present invention will utilize this feature to optimize the UE receiver. The adaptive receiver will simultaneously introduce the MMSE module and the sphere decoding module, and adaptively receive the appropriate receiving module according to the channel characteristics to receive the signal, in order to achieve the best reception performance and calculation. The purpose of power consumption is as low as possible.

3 is a schematic structural diagram of a space division multiplexing receiver according to an embodiment of the present invention. As shown in FIG. 3, the space division multiplexing receiver includes: a control decision module, a minimum mean square error estimation MMSE module, and a sphere decoding module. And a decoding module; wherein

The control decision module is configured to perform control decision, and the decision is processed by the MMSE module or the spherical decoding module to notify the corresponding module;

The MMSE module is configured to process the received signal after receiving the processing notification of the control decision module; The ball decoding module is configured to process the received signal after receiving the processing notification of the control decision module;

The LTE spatial division multiplexing receiver further includes a front end module and a channel estimation module; wherein the front end module is configured to receive an air interface signal, and process the air interface signal to obtain a frequency domain signal, for the MMSE module or the sphere translation The code module performs processing. Specifically, the front-end module receives the air interface signal, and after the RF front-end and digital front-end signal processing, the time domain signals are separated by symbols, the cyclic prefix is removed, and the frequency domain signal is obtained by performing FFT. ;

The channel estimation module is configured to extract reference symbols in the frequency domain signal, perform channel estimation, and obtain channel estimation values H(i, j) on each subcarrier, where the control decision module performs decision, wherein (i ) = , is 2 x 2 on the ith subcarrier of the jth OFDM symbol

Channel coefficient matrix.

The control decision module will analyze the channel characteristics and calculate the normalized determinant value.

^E{i , , the value is generally in the (0,1) interval,

The control decision module can make control decisions:

Receiving method selection control according to subcarriers: a first threshold is set in advance, E(i, j) is greater than the first threshold, and the MMSE module is used to receive the ith subcarrier of the jth OFDM symbol; otherwise, the decision is adopted. The sphere decoding module receives the ith subcarrier of the jth OFDM symbol; or

Receiving method selection control according to a subframe: presetting a second threshold and a third threshold, assuming that the number of all subcarriers in the i-th subframe is N, and calculating a subcarrier that satisfies E (i, j ) greater than the second threshold Number M; when M/N is greater than the third threshold, the decision uses MMSE mode The block receives all subcarrier data of the subframe. Otherwise, the decision uses the sphere decoding module to receive all subcarrier data of the subframe.

It should be noted that both the MMSE module and the sphere decoding module need to use the channel estimation value H(i, j) estimated by the channel estimation module for the processing of the received signal.

As a simplified derivative option, the E(i, j) being greater than the first threshold or the second threshold may be further reduced to A(i,j)>wx B(i,j)C(i,j), where , A(i,j) =

,

B(i, j) = + \c(i, ,

C(i, j) = max {\b(i, j% \d(i, + ^ {\b(i, j)\ + \d(i, , it should be noted that the invention is in other

O O

The above simplification can also be performed in similar situations. The above simplification greatly reduces the computational complexity and ensures that no additional computational load is introduced for the adaptive receiver.

F{i,j) =| a(i,j) I ² + 1 b(i,j) I ² , G(i,j) =| c(i,j) | ² + 1 d(i,j ² ) The control decision module performs the control decision:

Receiving method selection control according to subcarriers: setting a fourth threshold t, the fourth threshold being greater than 1, when F(i, j)>tx G(i,j) or G(i, j)>tx F(i , j), the decision uses the sphere decoding module to receive the ith subcarrier of the jth OFDM symbol; otherwise, the decision is to use the MMSE module to receive the ith subcarrier of the jth OFDM symbol; or

The receiving method selection control is performed according to the subframe: the fifth threshold value 0 and the sixth threshold value V are set in advance, and the number of all subcarriers in the i-th subframe is N, and the calculation statistic satisfies F(i,j)>oxG(i , j) or G(i,j)>oxF(i,j) number of subcarriers M;; when MVN, <v, the decision is to use the MMSE module to receive all subcarrier data of the subframe; otherwise, The decision uses a sphere decoding module to receive all of the subcarrier data for the subframe.

G(i,j) =| c(i,j) I ² + 1 d(i,j) I ² , the control decision module performs the control decision as:

Receiving method selection control according to subcarriers: setting a seventh threshold t and an eighth threshold in advance, t,>l, when F(i, j) > t, x G(i,j) , or G(i,j)> t, xF(i,j), or E(i,j) is less than The eighth threshold, the decision is to use the ball decoding module to receive the ith subcarrier of the jth OFDM symbol; otherwise, the decision is to use the MMSE module to receive the ith subcarrier of the jth OFDM symbol, or

Receiving method selection control according to the subframe: preset a ninth threshold o, a tenth threshold V, and an eleventh threshold, assuming that the number of all subcarriers in the i-th subframe is N", and the calculation statistics satisfy F(i, j) > ο χ G(i,j) , or G(i,j)>oxF(i,j) , or E(i,j) is less than the first threshold number of subcarriers M"; when M" When /N"<v', the decision uses the MMSE module to receive all the subcarrier data of the subframe. Otherwise, the decision uses the sphere decoding module to receive all the subcarrier data of the subframe.

As other options, the UE may also extract part E (i, j) to analyze the channel space feature, and use the set threshold decision to use an appropriate receiver module. In other words, the control decision module may perform the control decision: E (i, j) pairs make control decisions.

The threshold can be optimized in engineering practice. In other words, the control decision module can also be used to adjust the threshold according to actual conditions.

The decision information of the subframe is used for the receiving method selection of the subframe, and/or the receiving method of the subframe after the subframe is selected, for example, the decision information using the subframe n can be used for the receiving method of the subframe. The selection can also be used for the method selection of the subsequent sub-frame n+m.

The invention also correspondingly proposes an air interface signal processing method, the method comprising: performing a control decision, and determining, by the MMSE method or the sphere decoding method, the frequency domain signal of the air interface signal;

Optionally, before the performing the control decision, the method further includes: Receiving an air interface signal, and processing the air interface signal to obtain a frequency domain signal; extracting reference symbols in the frequency domain signal, performing channel estimation, and obtaining channel estimation values H(i, j) on each subcarrier, where ,

b(ij

, is 2x2 on the ith subcarrier of the jth OFDM symbol

, c(,_)

Channel coefficient matrix,

The controlling decision is: selecting, according to the H(i, j), the controlling decision

For:

Optionally, the E(i, j) is greater than the first threshold or the second threshold is further reduced to A(i,j) > w XB(i,j)C(i,j) , where A( i,j) = \a(i,j)d(i,j)-b(i,j)c(i,j)

B(i, j) = - max {\a(i, \c(i, + - {\a(i, j)\ + \c(i, j

O O

C ( , j) = + \d ( , j

Optional, F(i,j)=\a(i,j)\ ² + \b(i,j)\ ² , G(i,j)=\c(i,j)\ ² + \d (i,j)\ ² , the control decision is as follows:

Setting a fourth threshold t, the fourth threshold is greater than 1, when F(i, j)>tx G(i,j) or G(i, j) > tx F(i,j), the decision is to use sphere decoding The module performs the ith subcarrier of the jth OFDM symbol Receiving; otherwise, the decision uses the MMSE module to receive the ith subcarrier of the jth OFDM symbol; or

The fifth threshold value 0 and the sixth threshold value V are set in advance, assuming that the number of all subcarriers in the i-th subframe is N, and the calculation statistics satisfy F(i, j) > οχ G(i, j) or G(i, j) >οχ F(i,j) number of subcarriers M,; When M, /N, < v, the decision uses the MMSE module to receive all subcarrier data of the subframe; otherwise, the decision uses a spherical decoding module All subcarrier data of the subframe is received. Optional, ^E( ,

F{i,j) =| a(i,j) I ² + 1 b(i,j) I ² , G(i,j) =| c(i,j) | ² + 1 d(i,j ² ) The control decision is made as follows: a seventh threshold t is set in advance, and an eighth threshold, t, >l, when F(i, j) > t, XG(i,j), or G(i, j) > fx F(i,j), or E(i, j) is less than the eighth threshold, the decision is to use the spherical decoding module to receive the ith subcarrier of the jth OFDM symbol; otherwise, the decision is MMSE The module receives the i-th subcarrier of the jth OFDM symbol, or

The ninth threshold o, the tenth threshold V, and the eleventh threshold are set in advance, assuming that the number of all subcarriers in the i-th subframe is N", and the calculation statistic satisfies F(i, j) > οχ G(i, j) , or G(i, j) > οχ F(i,j), or E(i,j) is less than the number of subcarriers of the first threshold M"; when M, VN"<v, the decision is adopted The MMSE module receives all the subcarrier data of the subframe. Otherwise, the decision uses the sphere decoding module to receive all the subcarrier data of the subframe.

Optionally, the performing the control decision is: extracting a part of the E (i, j) pair to make a control decision. Optionally, the method further includes: adjusting the threshold according to actual conditions.

Optionally, the decision information of the subframe is used for the receiving method selection of the subframe, and/or the receiving method of the subframe after the subframe is selected.

It should be noted that, the present invention may further provide a gating module (as shown in FIG. 4) to control the MMSE module, the sphere decoding module, and the decoding module. Specifically, for a specific subcarrier, if the control decision module Deciding to use the MMSE module, then the gating module will close the ball decoding module, and the gating module will pass the result of the MMSE module to the following decoding module; The policy module decides to use the sphere decoding module, then the strobe module will close the MMSE module, and the strobe module will pass the result of the sphere decoding module to the following decoding module; the decoding module collects the code block data for decoding.

It can be seen that the present invention adaptively selects the receiving algorithm for the spatial characteristics of the channel, achieving a good compromise between complexity and performance, that is, the performance is as good as possible, and the power consumption of the receiver is as small as possible.

Claims

A spatial division multiplexing receiver, characterized in that: the LTE space division multiplexing receiver comprises: a control decision module, a minimum mean square error estimation MMSE module, a sphere decoding module and a decoding module;

The LTE space division multiplexing receiver according to claim 1, wherein the LTE space division multiplexing receiver further includes a front end module and a channel estimation module;

The front end module is configured to receive an air interface signal, and process the air interface signal to obtain a frequency domain signal for processing by the MMSE module or the sphere decoding module;

H(i,j) = , which is 2 χ 2 on the ith subcarrier of the jth OFDM symbol

Channel coefficient matrix.

3. The space division multiplexing receiver according to claim 2, wherein: said control decision module performs control

The decision is:

The space division multiplexing receiver according to claim 3, wherein said E(i, j) is greater than said first threshold or second threshold is further simplified to A(i,j) > wx B (i,j)C(i,j), where

A(i, j) = + \c(i, ,

C ( , j) =

5. The space division multiplexing receiver according to claim 2, characterized in that

Setting a fourth threshold t, the fourth threshold is greater than 1, when F(i, j) > t XG(i,j) or G(i, j) > tx F(i,j), the decision is to use sphere decoding The module receives the ith subcarrier of the jth OFDM symbol; otherwise, the decision is to use the MMSE module to receive the ith subcarrier of the jth OFDM symbol; or

The fifth threshold value 0 and the sixth threshold value V are set in advance, assuming that the number of all subcarriers in the i-th subframe is

N,, calculate the number of subcarriers M satisfying F(i, j) > ο χ G(i,j) or G(i, j) > o χ F(i,j);; when M'/N When <v, the decision uses the MMSE module to receive all the subcarrier data of the subframe. Otherwise, the decision uses the sphere decoding module to receive all the subcarrier data of the subframe.

6. The space division multiplexing receiver according to claim 2, characterized in that ,

^{E( j)} ,

The ninth threshold o, the tenth threshold V, and the eleventh threshold are set in advance, assuming that the number of all subcarriers in the i-th subframe is N", and the calculation statistic satisfies F(i, j) > ο χ G(i,j ) , or G(i, j) > ο χ

F(i,j), or E(i,j) is less than the first threshold number of subcarriers M"; when M, VN" < v, the decision is to use the MMSE module for all subcarriers of the subframe The data is received. Otherwise, the decision uses the sphere decoding module to receive all subcarrier data of the subframe.

The space division multiplexing receiver according to claim 3 or 6, wherein the control decision module performs a control decision as: performing a control decision on the extracted portion E (i, j).

The spatial multiplexing receiver according to any one of claims 3 to 6, wherein the control decision module is further configured to adjust the threshold according to actual conditions.

The space division multiplexing receiver according to any one of claims 3 to 6, wherein the decision information of the subframe is used for selection of a receiving method of the subframe, and/or after the subframe The receiving method of the subframe is selected.

10. An air interface signal processing method, the method comprising:

The air interface signal processing method according to claim 10, wherein the Before the line control decision, the method also includes:

Receiving an air interface signal, and processing the air interface signal to obtain a frequency domain signal;

Extracting reference symbols in the frequency domain signal, performing channel estimation, and obtaining channel estimation values H(i, j) on each subcarrier, where (i) = , is the i th subcarrier of the jth OFDM symbol 2x2

Channel coefficient matrix,

The making control decision is: making a decision according to the H(i, j).

The air interface signal processing method according to claim 11, wherein the controlling decision is:

The air interface signal processing method according to claim 12, wherein the E(i, j) is greater than the first threshold or the second threshold is further simplified to A(i,j)>wxB(i, j) C(i, j), where

A(i, j) = \a(i, j) + \c(i, ,

C ( , j) = - max

14. The air interface signal processing method according to claim 11, wherein:

F{i,j) =| a(i,j) b(i,j) G(i,j) =| c(i,j) d(i,j) | ² , the control decision is: Setting a fourth threshold t, the fourth threshold is greater than 1, when F(i, j) > t XG(i,j) or G(i, j) > tx F(i,j), the decision is to use sphere decoding The module receives the ith subcarrier of the jth OFDM symbol; otherwise, the decision is to use the MMSE module to receive the ith subcarrier of the jth OFDM symbol; or

The fifth threshold value 0 and the sixth threshold value V are set in advance, assuming that the number of all subcarriers in the i-th subframe is N, and the calculation statistics satisfy F(i, j) > ο χ G(i, j) or G(i, j > o χ F(i,j) the number of subcarriers M,; When M'/N, < v, the decision uses the MMSE module to receive all subcarrier data of the sub-frame. Otherwise, the decision is spherical translation. The code module receives all of the subcarrier data for the subframe.

15. The air interface signal processing method according to claim 11, wherein:

,

^{E( j)} ,

G(iJ) =| c(i, j) I ² + 1 d(i, j) I ² , the control decision is as follows:

Setting a seventh threshold t, and an eighth threshold, t, >l, when F(i, j) > t, XG(i,j), or G(i, j) > fx F(i,j), Or E(i, j) is smaller than the eighth threshold, and the decision is to use the ball decoding module to receive the ith subcarrier of the jth OFDM symbol; otherwise, the decision is to use the MMSE module to the ith sub of the jth OFDM symbol. Carrier receiving, or,

The air interface signal processing method according to claim 12 or 15, wherein the performing the control decision is: extracting a part E (i, j) pair to perform a control decision.

The air interface signal processing method according to any one of claims 12 to 15, wherein the method further comprises: adjusting the threshold according to an actual situation.

The air interface signal processing method according to any one of claims 12 to 15, characterized in The decision information of the subframe is used for the selection of the receiving method of the subframe, and/or the method of receiving the subframe after the subframe is selected.