WO2007137490A1

WO2007137490A1 - Signal transmitting and receiving method of mimo system and apparatus thereof

Info

Publication number: WO2007137490A1
Application number: PCT/CN2007/001572
Authority: WO
Inventors: Bin Li; Linfeng Xia; Shengrong Feng; Yinggang Du
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2006-05-15
Filing date: 2007-05-15
Publication date: 2007-12-06

Abstract

A signal transmitting and receiving method of a MIMO system and an apparatus thereof, which enable the code rate of complete diversity of four or more than four transmitting antennas to be not less than 1. The MIMO system transmits signals using KM goups of antennas in which two antennas is one group, wherein K, M are integers which are greater than 0 and KM>1; the method includes the following steps: 2KM transformation results are obtained from 2KM parallel signals that are to be transmitted through the linear combination, the 2KM transformation results are recombined into KM result groups with two being one group; the two transformation results in each result group include the linear transformation of 2KM signals; KM result groups are encoded using twin antenna time-space code, the code rate of which is 1; the signal encoded are separately transmitted through KM groups of antennas, K groups of antennas transmit signals simultaneously at every turn.

Description

Multi-input multi-output system signal transmitting and receiving method and device thereof

This application is required to be submitted to the China Patent Office on May 15, 2006, and the application number is 200610079787.0. The Chinese patent application entitled "Multiple Input Multiple Output System Signal Transmitting Method and Its Device" was submitted to China on June 20, 2006. The Patent Office, application number is 200610091970.2, and the Chinese patent application entitled "Multiple Input Multiple Output System Signal Transceiver Method and Its Device" was submitted to the Chinese Patent Office on June 23, 2006, the application number is 200610093901.5, and the invention name is "Multiple Input Multiple Output System Signal Transmitting Method and Transceiver," the three priority of the Chinese patent application, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD The present invention relates to the field of wireless communications, and in particular, to multiple input multiple outputs (Multiple Input Multiple Outputs)

Output, referred to as "MIMO") System signal transmission and reception method and device thereof.

Background technique

Current Wireless Local Area Network ("WLAN") technologies are facing limitations such as limited bandwidth and transmit power, interference, signal attenuation, and multipath effects (echoes and reflections that cause interference). With the development of the current situation, the convergence of future mobile communication broadband wireless mobile and wireless access has become a hot research topic, and MIMO system is one of the more research directions. MIMO technology will become an effective means to solve these problems. It can improve the throughput, transmission distance and reliability of WLAN, and is one of the most important technologies in the wireless field.

A MIMO system has twice the system capacity than a conventional antenna system, and signals are transmitted and received through multiple antennas at the transmitting end and the receiving end, thereby improving the quality of service for each user, for example, bit error rate or data rate. However, the conventional communication system uses a single-input and single-input (SISO) antenna system. In addition, Multiple-Inputs and Single-Output (MISO) and Single-Input and Multiple-Outputs (SIMO) based on transmit diversity and receive diversity are also used. It belongs to the implementation of the MIMO system, but the multi-input and multi-output methods are implemented at both ends of the communication to achieve the best results.

Space-time coding is the basis of MIMO systems, and next-generation wireless communication systems are planned to adopt spatio-temporal processing. People are also constantly proposing new or improved space-time codes (Space-Time Coding, referred to as The "STC" method improves the performance of the MMO system, reduces the complexity of the space-time coding system, and is better suited to the requirements of the new generation wireless communication system and the actual situation of the channel.

STC technology is an important topic. It utilizes two-dimensional coding of time and space to maximize the transmission rate in wireless channels to meet the technical requirements of next-generation wireless communication. The general structure of STC technology is shown in Figure 1. .

The physical essence of STC technology lies in: using the orthogonal or quasi-orthogonal characteristics existing between the airspace and the time domain, according to a design criterion, the coding redundancy information is mapped as evenly as possible to the space-time two-dimensional plane to weaken the wireless multipath. The negative effects of spatially selective fading and time-selective fading caused by propagation, thereby achieving high-reliability high-speed data transmission in wireless channels.

STC mainly includes the following four categories: Layered Space-Time Coding (abbreviation)

"LSTC,,", Space-Time Block Coding ("STBC"), Space-Time Trellis Coding ("STTC"), and space-time "Turbo" code. More complex STC The scheme is various cascade structures of the above-mentioned types of STCs, and the implementation complexity and performance of various types of STCs are different.

In addition, in order to achieve high-rate transmission, antenna diversity techniques are applied to both the transmitting end and the receiving end of the MMO system to reduce the correlation of the transmission path to achieve higher channel capacity.

In the wireless environment, multipath propagation is the main cause of channel fading, and Antenna Diversity is a typical technique for resisting channel fading. Traditionally, antenna diversity techniques process signals received from a plurality of spatially uncorrelated receiving antennas that are transmitted from the transmitting end and propagated through different paths. Therefore, antenna diversity is simultaneously received by antenna diversity. The probability of a signal with severe fading distortion is small, which can effectively improve the transmission quality of the signal, and the anti-channel fading of the 4th.

The "Alamouti" space-time code is a simple and effective space-time coding applied to two transmit antennas and multiple receive antennas. As shown in Figure 2, the code rate is 1 and the full diversity effect is achieved, as shown in Figure 3. Among them, the full diversity effect, that is, the diversity degree is the number of transmitting antennas 2; the code rate is defined as the ratio of the number of symbol symbols to the number of transmitting slots.

When the number of antennas is 2, the STC adopts the "Alamouti" space-time code. As shown in Fig. 2 and Fig. 3, the code rate of the transmitting antenna can be 1 and the effect of full diversity can be achieved. Wherein the input signal "S !, S _2, ..." by the first serial-parallel converted two parallel data streams, each parallel data for Si and S _2, respectively, Transmitted in two symbol symbols and on two transmit antennas. Specifically, data 8 and S ₂ * are respectively transmitted in two symbol symbols of the antenna 1, and data S ₂ and -Sj* are respectively transmitted in two symbol symbols of the antenna 2, where S!* is Si conjugated, S ₂ * S ₂ is conjugated.

When the number of antennas is 4, orthogonal space-time codes are usually used in the prior art. Orthogonal space-time codes can achieve full diversity, but the code rate is 3/4.

In practical applications, the above solution has the following problem: for four or more transmit antennas, the full diversity code rate is less than one.

Summary of the invention

In view of this, the embodiments of the present invention provide a method for transmitting and receiving signals of a multiple input multiple output system and a device thereof, so that the code rate of the full diversity is not less than 1 for four or more transmit antennas.

To achieve the above objective, an embodiment of the present invention provides a signal transmission method for a multiple input multiple output system, in which a transmitting end transmits signals by two groups of KM group antennas, where K and Μ are integers greater than 0 and ΚΜ>1 The method includes:

Two transform results are obtained from two parallel signals to be transmitted by linear transformation, and two transform results are reorganized into two groups into KM result groups; two transform results in each result group include 2KM a linear combination of signals;

The KM result groups are respectively coded with a double antenna space-time code with a code rate of 1;

The encoded signals of the KM result sets are respectively transmitted through the KM group antenna, and each round is simultaneously transmitted by the K group antenna.

The embodiment of the invention further provides a signal receiving method for a multiple input multiple output system, wherein the signal is transmitted by using two groups of KM group antennas, wherein K is the number of antenna groups simultaneously transmitted, and K and Μ are greater than An integer of 0 and ΚΜ>1; the number of receiving antennas is not less than Κ; the method includes:

Detecting 2 received signals in 2 symbol symbols;

According to the linear transformation of the received signal before transmission and the dual antenna space-time code coding with a code rate of 1, two parallel signals are obtained from the two received signals.

The embodiment of the present invention further provides a signal input device for a multiple input multiple output system, comprising: a KM group antenna of two groups, KM coding modules and a transform unit corresponding to each group of antennas, where M is greater than An integer of 0 and KM>1, where:

a transform unit for obtaining 2KM by 2KM parallel signals to be transmitted by linear transformation Transforming the result, and outputting to 1 coding module as 2 sets of 2 transform results; 2 transform results in each set include linear combination of 2KM parallel signals;

KM coding modules for encoding the input two conversion results with a dual antenna space-time code with a code rate of 1;

The KM group antenna is used for transmitting signals encoded by the corresponding coding module, and each round is simultaneously transmitted by the K group antennas.

The embodiment of the invention further provides a signal receiving device for a multiple input multiple output system, wherein the signal is transmitted by using two groups of KM group antennas, wherein K is the number of antenna groups simultaneously transmitted, and K and Μ are greater than An integer of 0 and ΚΜ>1; the device includes at least one receive antenna, and:

a serial transfer module for converting 2 接收 received signals detected by the receiving antenna within 2 码 symbol symbols into parallel received signals and outputting to the signal recovery unit;

And a signal recovery unit, configured to perform linear transformation according to the received signal before transmission and dual antenna space-time code coding with a code rate of 1, and obtain two parallel signals from the two received signals.

An embodiment of the present invention further provides a signal receiving apparatus for a multiple input multiple output system, wherein the signal is transmitted in turn by two groups of two groups of antennas, wherein Ν is an integer greater than one; 1 receiving antenna, and:

a decoding module, configured to decode two received signals detected in each of the two symbol symbols into two decoding results; and the decoding is performed according to a dual antenna space-time code with a code rate of 1 before the receiving of the received signal;

The signal inverse transform unit is configured to obtain two parallel signals from the two decoding results of the decoding according to the linear transformation performed before the transmission of the received signal.

In the embodiment of the present invention, two transform results are obtained by linear transformation from two parallel signals to be transmitted, and two transform results are reorganized into two groups into KM result groups, and the KM result groups are coded at a rate of one. Dual antenna space-time code coding, transmitted on the KM group antenna. Because the 2KM signals to be sent are linearly transformed and recombined into KM groups for encoding, and finally sent to KM for antenna transmission, each signal is transmitted via 2KM antennas, with full diversity effect and good transmission performance. And transmitting in the M round by K to the antenna, the code rate is not less than 1.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a general structural diagram of an STC technique of a MIMO system in the prior art; 2 is a schematic diagram of an "Alamouti" space-time code scheme of a MIMO system in the prior art; FIG. 3 is a schematic diagram of an "Alamouti" space-time code according to the MIMO system shown in FIG. 2 in the prior art;

4 is a flowchart of a signal transmission method of a MIMO system according to a first embodiment of the present invention; FIG. 5 is a schematic diagram of a transmission scheme of a 4-antenna system according to a first embodiment of the present invention; FIG. FIG. 7 is a flowchart of a MIMO system signal transmission method according to a second embodiment of the present invention; FIG. 8 is an STC scheme of an 8-antenna system according to a second embodiment of the present invention; FIG. 9 is a schematic diagram of an STC of an 8-antenna system according to a second embodiment of the present invention shown in FIG. 8. FIG. 10 is a flowchart of a MIMO system signal receiving method according to a third embodiment of the present invention; FIG. FIG. 12 is a structural diagram of a signal transmitting apparatus of a MIMO system according to a fourth embodiment of the present invention; FIG. 13 is a signal receiving apparatus of a MIMO system according to a fifth embodiment of the present invention; FIG. 14 is a flowchart of a MIMO system signal transmitting method according to a sixth embodiment of the present invention; FIG. 15 is a sixth aspect of the present invention. FIG. 16 is a flowchart of a MIMO system signal receiving method according to a seventh embodiment of the present invention; FIG. 17 is a structural diagram of a MIMO receiver according to a ninth embodiment of the present invention;

18 is a structural diagram of a MIMO receiver according to a thirteenth embodiment of the present invention;

FIG. 19 is a flowchart of a transmission method of a MIMO system according to a sixteenth embodiment of the present invention; FIG. 20 is a schematic diagram of a transmission scheme of a four-antenna system according to a sixteenth embodiment of the present invention; FIG. STC diagram of a four-antenna system of a sixteenth embodiment of the present invention;

Figure 22 is a flowchart of a signal transmission method of a MIMO system according to a seventeenth embodiment of the present invention; Figure 23 is a schematic diagram of an STC scheme of a four-antenna system according to a seventeenth embodiment of the present invention; FIG. 25 is a schematic diagram of an STC scheme of an 8-antenna system according to an eighteenth embodiment of the present invention; FIG. 26 is an eighth embodiment of the eighteenth embodiment of the present invention shown in FIG. STC diagram of the antenna system;

FIG. 27 is a flowchart of a method for transmitting a MIMO system signal according to a nineteenth embodiment of the present invention; FIG. 28 is a schematic diagram of an STC scheme of an 8-antenna system according to a nineteenth embodiment of the present invention; FIG. 29 is a structural diagram of a MIMO system signal transmitting apparatus according to a twentieth embodiment of the present invention; and FIG. 30 is a twentieth according to the present invention. A structural diagram of a signal receiving apparatus of a MIMO system according to a second embodiment;

Figure 31 is a structural diagram of a signal receiving apparatus of a MIMO system according to a twenty-fifth embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION In order to make the objects, technical solutions and advantages of the present invention more comprehensible, the present invention will be further described in detail with reference to the accompanying drawings.

The embodiment of the present invention provides a space-time coding scheme for four or more transmit antennas with a code rate of not less than 1 and full diversity. First, a transform result is obtained by a linear transform from a signal to be transmitted, and the transform result is obtained. Two groups are combined and encoded by a pair of antennas with a code rate of 1 and then output by K to the antenna. At the receiving end, decoding and inverse transform corresponding to the transmitting end are used to obtain the transmitted signal.

The MIMO system signal transmission method according to the first embodiment of the present invention is as shown in FIG.

2N transmit antennas, 2N antennas are divided into 1 groups into N groups, where N is an integer greater than 1. When N=2, 4 transmit antenna antennas 1 and 2 are a group, and antenna 3 and antenna 4 are a group. The STC scheme of the MIMO system adopts orthogonal transform and "Alamouti" space-time code as shown in Fig. 5. Show.

In step 401, the transmitting end of the MIMO system converts four (2N) serial signals in the serial signal stream to be transmitted, for example, signals Xi, X ₂ , X ₃ and X ₄ , after serial-to-parallel conversion. The corresponding four parallel signals are obtained, and the subsequent signals are equally converted every four to obtain a parallel signal stream. The present invention is applied to the transmission of a serial signal stream by serial transfer.

In step 402, the parallel signal stream four parallel signals are converted into two groups, for example, and for the first group _2, X _3, X ₄ of the second group.

In step 403, the signals of the two transform groups are linearly transformed, and each transform group is generated.

2 transformation results. Wherein, the signal of the first group and the result of the transformation are 8 ₁ and 8 ₃ ; the signal of the second group X ₃ and the resulting transformation result are 8 ₂ and S ₄ .

The linear transformation performed may be an orthogonal transform, such as a Fast Fourier Transform ("FFT"), a Hadamard Transform, and a metamorphosis. By changing, the signal code words sent in the present embodiment can be orthogonalized, thereby further improving the transmission performance, and also having good performance when the receiving end performs inverse transform to obtain signals, X ₂ , ... X ₈ .

Taking the Hada code transformation as an example, the transformation result is:

(X3 - X4) / /Ϊ.

In step 404, the four transformation results obtained by the signals of the two transformation groups are reorganized into two result groups by two groups, and that 8 ₁ and 8 ₂ form a first result group, and S ₃ and S ₄ constitute a group. Two result groups. The principle of recombination is that the two transformation results in each result group are required to come from different transformation groups.

In step 405, the two result sets are respectively encoded with a two-antenna space-time code of code rate 1, for example, an "Alamouti" space-time code.

In step 406, the two sets of transmit antennas respectively transmit the signals encoded by the double-antenna space-time code of the code rate of 1 in the two result sets, wherein each set of antennas continuously transmits 2 symbol symbols. When the "Alamouti" space-time code is used, the STC output by the four transmitting antennas is as shown in Fig. 6. Since the first result set encoded signal and the second result set encoded signal are transmitted in different antenna groups and at different times, they do not interfere with each other. Only one pair of antennas transmits the signal encoded by the "Alamouti" space-time code in each time period, so that the code rate of the full diversity of the "Alamouti" space-time code is 1 and the code word is orthogonal.

Because the four parallel signals to be transmitted are linearly transformed, and reorganized into two result groups for "Alamouti" space-time code encoding, and finally sent to a pair of antenna transmissions, for example, 8 ₁ and 8 ₂ are transmitted by a pair of antennas, S ₃ and S ₄ are sent by another pair of antennas, and 8 ₁ = ( + ₂ ) / 2 , S ₂ = ( X3 + X4 ) / V2 ; S ₃ = ( Xj - X ₂ ) / V2 , S ₄ = ( X3 - X4 ) / V2 , so each of the signals of x ₂ , x ₃ and is transmitted via each of the four antennas, with a full diversity effect of 4 antennas, and good transmission performance.

The MIMO system signal transmission method according to the second embodiment of the present invention is as shown in FIG. 7. When N=4, eight (2N) transmit antenna antennas 1 and 2 are a group, and antenna 3 and antenna 4 are a group. The antenna 5 and the antenna 6 are a group, and the antenna 7 and the antenna 8 are a group. The STC scheme of the MIMO system is as shown in FIG. 8 when orthogonal transform and "Alamouti" space-time code are employed.

In step 701, the transmitting end of the MIMO system converts 8 (2N) serial signals in the serial signal stream to be transmitted, for example, signals Χι, X ₂ , ... X ₈ , after serial-to-parallel conversion. Get the corresponding 8 Parallel signals, the subsequent signals are equally converted every 8 to obtain a parallel signal stream. The present invention is applied to the transmission of a serial signal stream by serial transfer.

In step 702, the eight parallel signals in the parallel signal stream are equally divided into two transform groups, for example,

Xi, X ₂ , X ₃ and X ₄ are the first group, and X ₅ , X ₆ , X ₇ and X ₈ are the second group.

In step 703, the signals of the two transform groups are linearly transformed, and each transform group is generated.

4 transformation results. Wherein, the conversion result of the first group of signals, X ₂ , X ₃ and X ₄ is Si, S ₃ ,

S ₅ and S ₇ ; the second set of signals X ₅ , X ₆ , X ₇ and X ₈ result in transformations S ₂ , S ₄ , S ₆ and S ₈ .

The linear transformation performed may be an orthogonal transform, such as an FFT, a Hada code transform, or the like. In step 704, a signal converting two sets of eight converting the obtained junction Gao 1 to 2 groups as a result of recombinant four groups, 8! And S ₂ are the results of a first group consisting of, S ₃ and S ₄ Composition The second result set, S ₅ and s ₆ constitute a third result set, and s ₇ and s ₈ form a fourth result set. The principle of recombination is that the two transformation results in each result group are required to come from different transformation groups.

In step 705, the four result sets are respectively encoded with a two-antenna space-time code of a code rate of 1, for example, an "Alamouti" space-time code.

In step 706, the four sets of transmit antennas respectively transmit the signals encoded by the double-antenna space-time code of the code rate of 1 in the four result sets, wherein each set of antennas continuously transmits two symbol symbols. When using the "Alamouti" space-time code, the STC output by these 8 transmit antennas is shown in Figure 9. Similarly, the coded signals of the different result sets are transmitted in different antenna groups and at different times, and therefore do not interfere with each other.

A MIMO system signal receiving method according to a third embodiment of the present invention is shown in FIG. In this embodiment, the signal transmitting end includes N sets of transmitting antennas in a group of two, and the number of transmitting antenna groups is 1 at the same time, and the number of receiving antennas at the receiving end is 1.

In step 1001, when the receiving end of the MIMO system receives the signal, the signal received in the two symbol symbols is correspondingly decoded by the dual antenna space-time code with the code rate of 1 used by the transmitting end, for example, "Alamouti""Time and space code. Two signals are obtained per decoding. For example, when receiving signals from antenna 1 and antenna 2 (including two consecutive symbols), decoding results in 8 ₁ and 8 ₂ ; signals from antenna 3 and antenna 4 are received (including two consecutive symbols) At the time, decoding results in S ₃ and S ₄ .

In step 1002, the 2N signals obtained by successive N decodings are equally divided into two groups, and the N signals in each group are respectively derived from N different decoding results. Where N is an integer greater than one. example For example, when N = 2 and the transmitting end uses the orthogonal transform as shown in Fig. 11, for the signal transmitted by the 4-antenna system, the decoding is performed twice to obtain 4 signals, which are divided into 2 groups, the first group is 8 ₁ And 8 ₃ , the second group is S ₂ and S ₄ .

In step 1003, an inverse transform corresponding to the linear transformation of the transmitting end is performed for each of the N signals in each group, and N transform results are obtained for each group. Wherein, if the linear transformation at the transmitting end is an orthogonal transform, for example, an FFT, a Hada transform or a cosine transform, the inverse transform of the orthogonal transform of the signals is used to obtain N transform results; when N = 2, as shown in FIG. the results obtained after two converted signals in each group after the two signals inverse orthogonal transform, the first group of 8! S _3, and an inverse orthogonal transform and signal _2, and a second set S ₂ of S ₄ for The signals X ₃ and X _{4 are} obtained after orthogonal inverse transformation.

In step 1004, the two sets of transform results are combined into 2N parallel signal outputs.

In step 1005, 2N parallel signals are converted to a serial signal stream output.

In the embodiment, the MIMO system signal receiving method is described by taking N=2 as an example. It is easy for those skilled in the art to understand that when N takes other integer values greater than 1, the signal receiving manner of the MIMO system is similar. No longer.

As shown in FIG. 12, the MIMO system signal transmitting apparatus according to the fourth embodiment of the present invention includes N sets of antennas of two groups, and N coding modules 1231 and 1232 corresponding to N sets of antennas up to 123N. The serial conversion module 1210 and the transform unit 1220 include two linear transform modules 1221 and 1222, where N is an integer greater than one.

Specifically, the serial-to-transfer module 1210 is configured to convert the serial signal stream to be transmitted into 2N parallel signals, and divide them into two groups and output them to two linear transform modules 1221 and 1222, respectively. The group signal is linearly transformed into N transform results and output to N coding modules 1231, 1232 to 123N, respectively, and then these transform results are encoded by each coding module with a two-antenna space-time code with a code rate of 1, and output to the corresponding 1 set of antennas; the N sets of antennas transmit signals from corresponding coding modules in turn.

Wherein, if the linear transformation in the transmitting device adopts orthogonal transform, the codewords output to each group of antennas are orthogonal, and the corresponding inverse transform is easily implemented, so that the structure of the receiving device can be relatively simple; The antenna space-time code can be the "Alamouti" space-time code. Because the 2N signals to be sent are linearly transformed, and reorganized into N groups for "Alamouti" space-time code encoding, and finally sent to a pair of antennas, each signal is transmitted via 2N antennas, with 2N antennas. Full score Set effect, good transmission performance.

In the present embodiment, the transform unit 1220 includes two linear transform modules 1221 and 1222. The basic function of the two linear transform modules is that each input signal can be distributed to each antenna for linear transmission after being transformed by the transform unit 1220. It can be understood that the same effect can be achieved if the transform unit 1220 linearly transforms all 2N signals together using only one linear transform module.

The MIMO system signal receiving apparatus according to the fifth embodiment of the present invention is configured as shown in FIG. 13 and is configured to receive 2N transmit antennas and a transmission signal having a code rate of 1. The receiving apparatus includes an antenna, a decoding module 1310, and two linear transform modules. 1321 and 1322, and a parallel-to-serial module 1330.

Specifically, the decoding module 1310 is configured to decode each of the two received signals received by the antenna with an "Alamouti" space-time code to obtain two signals, which are respectively output to the linear transform modules 1321 and 1322. The decoding module 1310 decodes the signal received by the antenna, and the N decoding results are collected and then inversely transformed by the two linear transform modules 1321 and 1322 respectively; and each linear transform module performs linearity with the transmitting end for the N input signals. Transform the corresponding inverse transform to obtain a signal output. Finally, the 2N parallel signals output by the two linear transform modules 1321 and 1322 are converted to a serial signal output by the parallel-to-serial module 1330. Wherein, the linear transformation may be an orthogonal transformation.

In the fifth embodiment, two linear transform modules are used, the basic function of which is to cause the receiving device to perform a packet linear transformation inverse to the transmitting end of the received signal. It can be understood that if the receiving signal transmitting end linearly transforms all 2N signals, the receiving device in this embodiment can obtain the corresponding 2N parallel signals by using only one linear transform module.

A four-antenna MMO system signal transmitting method according to a sixth embodiment of the present invention is shown in Figs. 14 and 15. The sixth embodiment is similar to the first embodiment except that the first embodiment employs two transform groups for linear transformation, and the sixth embodiment performs linear transformation with only one transform group. In Figure 14, step 1401 is similar to step 401 of the first embodiment, step 1403 is similar to step 405, and step 1404 is similar to step 406, and details are not described herein again.

In step 1402, the four parallel signals generated after the serial-to-parallel conversion are linearly transformed to generate four signals, and the two signals are grouped into two result groups, so that the code rate is 1 in step 1403. Antenna space-time code coding.

The STC scheme of the MIMO system in this embodiment adopts orthogonal transform and "Alamouti" space-time The code time is shown in Figure 15.

A signal receiving method for a 4-antenna MIMO system according to a seventh embodiment of the present invention is shown in FIG. The seventh embodiment corresponds to receiving the signal transmitted by the sixth embodiment.

In step 1601, the receiving end decodes the received signal (including 2 consecutive symbols) of the "Alamouti" space-time code to obtain two signals. Four signals can be obtained by two consecutive decodings.

Thereafter, the process proceeds to step 1602, and the four signals obtained by the two consecutive decodings are subjected to linear inverse transformation, and the manner of the linear inverse transformation is opposite to the manner of linear transformation in the sixth embodiment, and the purpose is to recover from the four signals obtained by decoding. Out of 4 original signals. The linear transformation can be an orthogonal transformation, and the use of orthogonal transformation can suppress noise and improve signal quality.

Thereafter, proceeding to step 1603, the four parallel signals obtained by the linear transformation are converted into serial signal outputs.

The eighth embodiment of the present invention is a receiving method in which four transmitting antennas and one receiving antenna, the code rate is 1, and the transmitting end encodes with an "Alamouti" space-time code, and can be used to receive the signal transmitted by the first embodiment. Assuming that the channel parameters corresponding to four transmit antennas and one receive antenna are (h _x , h ₂ , h„h, ), the received signals ^ , r ₂ , r ₃ , r _{4 in the} four symbol symbols can represent for:

Here, / , « ₃ , /7 ₄ are the noise sample values within the four symbol symbols, respectively, assuming a Gaussian distribution with zero mean and the same variance ² . The above formula can be further expressed as:

_

Assume that the linear transformation (typically an orthogonal transformation) used by the sender is:

Can get: R = HH _NT X ~~ N (4)

Based on the receiver of the Minimum mean-square error (MMSE) criterion, the detection of the signal is:

) H" _T H" _H R (5)

Here, it represents the estimated value of X, /„ is the diagonal unit matrix, the superscript "-1" represents the inversion of the matrix, H^ represents the common transposition of ^^, and H^ represents the transposition of H _EH . .

A ninth embodiment of the present invention is a single receiving antenna MMO receiver for encoding a 4 transmitting antenna, a code rate of 1, and a transmitting end using an "Alamouti" space-time code, and its structure is as shown in FIG. Inputting the signal sequence in the symbol symbol received from the receiving antenna, Α, ... into the serial and module

1710, converted from serial to parallel in groups of four.

The parallel receiving signals outputted by the serial and module 1710 are input to the conjugate processing module 1721, and r ₂ and r ₄ having an even number in the parallel received signals are conjugated, and the serial number is maintained as an odd number, and r _{3 is} unchanged. The processing result is output as a vector ? = to the matrix multiplication module 1723,

In the matrix calculation module, the moment c =

And the matrix C is also output to the matrix multiplication module 1723.

The matrix multiplication module 1723 multiplies the matrix C by the vector R to obtain the detection result.

Of course, the matrix multiplication module 1723 outputs four sets of parallel signals. If serial results are required, a parallel and serial module can be added after the matrix multiplication module 1723.

In this embodiment, the conjugate processing module 1721, the matrix calculation module 1722, and the matrix multiplication module

1723 can constitute a signal recovery unit 1720 to recover the received signal detected in each symbol symbol. For parallel signals.

A tenth embodiment of the present invention is a receiving method in which eight transmitting antennas and one receiving antenna, the code rate is 1, and the transmitting end encodes with an "Alamouti" space-time code, and can be used to correspondingly receive the signal transmitted by the second embodiment. Assuming that the channel parameters corresponding to eight transmit antennas and one receive antenna are (h _x , /? ₂ , Ζζ ₃ , Α ₄ , /? ₅ , Α ₆ , /? ₇ , ), then within eight symbol symbols The received signals r„r ₂ , r ₃ , r , r ₅ , r ₆ , r ₇ , r ₈ can be expressed as:

Here, the noise sample values in the eight symbol symbols are assumed to be Gaussian distribution, zero mean and the same variance ⁰ ". The above equation can be further expressed as:

Assume that the linear transformation (typically orthogonal transformation) adopted by the sender is:

4

Can get:

R = H _R „H _NT X + N (9)

h ₂ 0 0 0 0 0 0

-h ₂ * K 0 0 0 0 0 0

0 0 κ 0 0 0 0

0 0 - h 0 0 0 0

0 0 0 0 h ₅ h ₆ 0 0

0 0 0 0 0 0 η _Ί h

0 0 0 0 0 0 - h h. w ₁₂ w ₁₃ w ₁₄ w ₁₅ w ₁₆ w ₁₇ w ₁₈

w ₂₁ w ₂₄ ^W 27

w ₃₁ ^32 ^W 37

w ₄₁ ^W 47

w ₅₃ W54 ^W 57

w ₆₁ w ₆₃ ^W 67 ^W 68

w ₇₃ W75

W _S1 w ₈₂ w ₈₃ w ₈₄ w ₈₅ w ₈₆ w ₈₇ w ₈₈

For receivers based on the MMSE criteria, the detection of the signal is:

^ = (^or H " _H H _CH Η _ΟΤ + σ^Ι _Η ) Η" _Τ Η" _Η R (10)

Where, represents the estimated value of X.

The eleventh embodiment of the present invention is a single receive antenna MIMO receiver for encoding 8 transmit antennas, a code rate of 1, and a transmit end using an "Alamouti" space-time code. The structure is similar to that of FIG. 17, except that the parallel transmission signals between the modules are 8 instead of 4. The signal sequence in the symbol symbol received from the receiving antenna, ι^ Α, ... is input to the serial to the module, and the 8 groups are serially connected. Switch to parallel.

The parallel receiving signals outputted by the serial and module are input to the conjugate processing module, and r2, r4, r6, r8 with the even number of the parallel received signals are conjugated, and the rl, r3, r5 with the odd number are maintained. R7 does not change,

Will

The matrix C is also output to the matrix multiplication module.

The matrix multiplication module multiplies the matrix C by the vector R to obtain the detection result.

Of course, the matrix multiplication module outputs eight sets of parallel signals. If serial results are required, a parallel and serial module can be added after the moment P multiply the module.

In this embodiment, the conjugate processing module, the matrix calculation module, and the matrix multiplication module may constitute a signal recovery unit, and restore the received signals detected in the respective symbol symbols to parallel signals.

A twelfth embodiment of the present invention is a receiving method in which four transmitting antennas and one receiving antenna, the code rate is 1, and the transmitting end encodes with an "Alamouti" space-time code, and can be used to receive the signal transmitted by the first embodiment. In the present embodiment, the ML (Maximum Likelihood) algorithm is used, specifically, for each possible detection result _{4, the} corresponding Z _K = {RH _CH H _OT X _K ) ^H {RH _CH H _{OT is} calculated. X _K )\ where'

X, for

One possible value of ^2; a letter X _A corresponding to four transmit antennas and one receive antenna

The channel parameter; r _l5 r ₂ , r ₃ , r ₄ is the received signal of the receiving antenna in four symbol symbols, representing the conjugate of η; Η _ητ is the linear transformation matrix of the transmitting end. The minimum value is searched for in all ^, and the corresponding value of the minimum value is output as a detection result. For the case of four transmit antennas, X is a group of four signals, each signal may take 0 or 1, and the possible detection results _fc are 2 ⁴ = 16 for each type. , there are a total of 16 Z _fc , and then find the minimum value, which corresponds to it; ^ as the test result.

A thirteenth embodiment of the present invention is a single receiving antenna MIMO receiver corresponding to four transmitting antennas, having a code rate of 1, and transmitting at the transmitting end using an "Alamouti" space-time code, and its structure is as shown in FIG.

The signal sequence in the symbol symbol received from the receiving antenna, ι· ₂ , . . . is input to the serial to serial module 1810, and is switched from serial to parallel in groups of four.

The parallel received signal signal outputted by the serial and module 1810 is input to the conjugate processing module 1821, and r ₂ and r ₄ having an even number in the parallel received signal are conjugated, and the rr ₃ having the odd number is maintained. The processing result is output to the ML algorithm module 1822 as a vector i?.

In the ML algorithm module 1822, the corresponding Z _k ={RH _CH H _OT X _k ) ^H {RH _CH H _OT X _k )' is calculated for each possible detection result, and the minimum value is searched for in all Z ₄ , the corresponding value of the minimum value; ^ is output as a detection result. among them,

In this embodiment, the conjugate processing module 1821 and the ML algorithm module 1822 may constitute a signal recovery unit 1820 to restore the received signals detected in the respective symbol symbols to parallel signals.

The fourteenth embodiment of the present invention is a receiving method in which eight transmitting antennas and one receiving antenna, the code rate is 1, and the transmitting end encodes with an "Alamouti" space-time code, and can be used to receive the signal transmitted by the second embodiment. This embodiment adopts an ML algorithm, specifically, for each possible detection result, its corresponding Z _A =(R - H _CH H _0T X _k ) ^H (R - H _CH H _OT X _k );

W _u W _n W ₁₃ W _H W ₁₅ W _i6 W ₁₇ W _ls

w ₂₁ w ₂₂ w ₂₃ w ₂₄ w ₂₅ w ₂₆ w ₂₁ w ₂₈

W3l ^w 32 W33 W34 ^35 W ₃₆ W ₃₇ W ₃₈

_{H =} ^41 w ₄₂ w ₄₃ w _M w ₄₅ w ₄₆ w A possible value for _A1 w ₄₈ ;

° ^T W ₅ 1 ^52 w ₅₃ w ₅₄ w ₅₅ w ₅₆ w ₅₇ w ₅₈

w ₆₁ w ₆₂ w ₆₃ w ₆₄ w ₆₅ w ₆₆ w ₆₇ w _6s

W71 ^w n W73 W ₇₄ W ₇₅ W ₇₆ w ₇₇ W _7S

8 ₁ w ₈₂ w _S3 w ₈₄ w _S5 w ₈₆ w ₈₇ w _S8

, A ₄ , is a channel parameter corresponding to eight receiving antennas and one receiving antenna; r _s is a receiving signal of the receiving antenna within eight symbol symbols, ^ represents a conjugate of η; Η _οτ is a linear transformation matrix of the transmitting end.

The minimum value is searched for among all, and the _FT corresponding to the minimum value is output as a detection result. For the case of eight transmit antennas, X is a group of eight signals, each of which may take 0 or 1. The combined possible detection result is 2 ⁸ = 256, and the corresponding is calculated for each. Ζ, , There are a total of 256 Z _T , and then find the minimum value, and the corresponding; ^ as the test result.

A fifteenth embodiment of the present invention corresponds to eight transmit antennas, a code rate of 1, and a transmit end

The "Alamouti" space-time code encoding single-receiver antenna MIMO receiver has a structure similar to that of FIG. 18, except that the signals transmitted in parallel between the modules in FIG. 18 are 4-way, and the signals transmitted in parallel in this embodiment are transmitted. It is 8 roads.

The signal sequence Ι^Α, Ι^ ... in the symbol symbol received from the receiving antenna is input to the serial conversion module, and is switched from serial to parallel in groups of eight.

The parallel receiving signals outputted by the serial and module are input to the conjugate processing module, and the parallel numbers of the received signals are evenly numbered r ₂ , r ₄ , r ₆ , r ₈ , and the number is odd. ΑΑ unchanged, will be The result is treated as a vector; ? = output to the ML algorithm module.

N53⁄4 3⁄4 _r r K26o5 * * *

In the ML algorithm module, for each possible test result; ^ calculate its corresponding Z _k = (R - H _CH H _OT X _k ) ^H (R - H _CH H _or X _k ); in all Z ₄ Search for the minimum value, and the corresponding value of the minimum value; ^ is output as the detection result. among them,

w ₁₂ w ₁₃ w ₁₄ w ₁₅ w ₁₆ w ₁₇

w.

W33 W34 W35 w ₃₆ W- w ₄₁ w ₄₆

w ₅₁ W52 W53 w ₅₆

w ₆₁ w ₆₃ w ₆₆ w ₆₇ w<

W73 W74 w ₇₆ w ₇₇ w.

w ₈₁ w ₈₂ w ₈₃ w ₈₄ w ₈₅ w ₈₆ w _{87 In the} present embodiment, the conjugate processing module and the ML algorithm module may constitute a signal recovery unit that restores the received signal detected in each symbol symbol to a parallel signal.

A MIMO system signal transmitting method according to a sixteenth embodiment of the present invention is as shown in FIG. 4N transmit antennas are preset, and 4N antennas are divided into 2 components into 2N groups, where N is an integer greater than 0. When N = l, 4 transmit antenna antennas 1 and 2 are a group, antenna 3 and antenna 4 are a group, and the STC scheme of the MIMO system is used when orthogonal transform and "Alamouti" space-time code are used. As shown in Figure 20.

In step 1901, the transmitting end of the MIMO system transmits four (4N) serial signals, for example, signals X ₂ , X ₃ and X ₄ , in the serial signal stream to be transmitted, and then obtains corresponding signals. The four parallel signals, the subsequent signals are equally converted every four, resulting in a parallel signal stream. The present invention is applied to the transmission of a serial signal stream by serial transfer.

In step 1902, the parallel signal stream four parallel signals are converted into two groups, for example, and for the first group _2, X _3, X ₄ of the second group.

In step 1903, the two sets of signals are linearly transformed, and each transform set generates two transform results. Wherein, the signal of the first group and the result of the transformation of ₂ are

S ₃ ; The results of the second set of signals _3⁄4 and x ₄ are s ₂ and s ₄ .

The linear transformation performed may be an orthogonal transform, such as a Fast Fourier Transform ("Front Fourier Transform"), a Hadamard Transform (Hadamard Transform), a cosine transform, etc., so that the receiving end can be performed at the receiving end. The inverse transform is easy to implement when obtaining signals, X ₂ , ... X ₄ , and has good performance.

Si = (Xi + x ₂ ) / ϊ , s ₃ = (Xi - x ₂ ) / ϊ , s ₂ = (x ₃ + x ₄ ) / 2 , s ₄ = (x ₃ - χ ₄ ) / ϊ.

In step 1904, the four transform results obtained by the signals of the two transform groups are reorganized into two result groups by two groups, and that 8 ₁ and 8 ₂ form a first result group, and S ₃ and S ₄ constitute a first group. Two result groups. The principle of recombination is that the two transformation results in each result group are required to come from different transformation groups.

In step 1905, the two result sets are respectively coded with a two-antenna space-time code of code rate 1, for example, "Alamouti" space-time code.

In step 1906, the two sets of transmit antennas respectively transmit two symbols of the two-antenna space-time code encoded by the code rate of two in the two result sets. When the "Alamouti" space-time code is used, the STC output by the four transmitting antennas is as shown in FIG. 21. Since each pair of antennas transmits a set of signals encoded by the "Alamouti" space-time code in each time period, the code rate of the full diversity can be made 2. Because the four signals to be transmitted are linearly transformed and reorganized into two groups for "Alamouti" space-time code encoding, and finally sent to a pair of antenna transmissions, for example, 8 and S ₂ are transmitted by a pair of antennas, S ₃ and S ₄ Sent by another pair of antennas, and ( Xj+X ₂ ) / 42 , S ₂ = ( X3+X4 ) / 2; S ₃ = ( Xi -X ₂ ) / V2 , S ₄ = (X3 - X4) / 2 , so each of X ₂ , X ₃ and X ₄ is transmitted via each of the 4 antennas with 4 antennas The full diversity effect and better transmission performance.

A MIMO system signal transmitting method according to a seventeenth embodiment of the present invention is as shown in FIG. 4N transmit antennas are preset, and 4N antennas are divided into 2 components into 2N groups, where N is an integer greater than 0. When N=l, four transmit antenna antennas 1 and 2 are a group, and antenna 3 and antenna 4 are a group. When orthogonal transform and "Alamouti" space-time code are used, the STC scheme of the MIMO system is as shown in Fig. 23. Show.

In step 2201, the transmitting end of the MO system transmits four (4N) serial signals in the serial signal stream to be transmitted, for example, signals, x ₂ , x ₃ and x ₄ , after serial-to-parallel conversion. corresponding

Four parallel signals, the subsequent signals are equally converted every four times to obtain a parallel signal stream. The present invention is applied to the transmission of a serial signal stream by serial transfer.

In step 2202, the parallel signal stream four parallel linear transformation signals, generates four transformation results S ^ S ^ S ₃ and S _4.

The linear transformation performed may be an orthogonal transform, such as a fast Fourier transform, a Hadamard transform, a cosine transform, etc., so that the inverse transform at the receiving end can be easily obtained when the signal, X ₂ , ... X4 is obtained. , have good performance.

(x ₃ -X4) / Ϊ.

In step 2203, the four transformation results generated by the linear transformation are divided into two result groups in groups of two, wherein, in groups of 8 ₁ and 8 ₃ , S ₂ and S ₄ are a group.

Steps 2204 to 2205 are similar to steps 1904 to 1905, respectively, and are not described herein.

A signal transmission method of a MIMO system according to an eighteenth embodiment of the present invention is as shown in FIG. 24, when N =

2, 8 (4N) transmit antenna antenna 1 and antenna 2 are a group, antenna 3 and antenna 4 are a group, antenna 5 and antenna 6 are a group, and antenna 7 and antenna 8 are a group. The STC scheme of the MIMO system when the transform and the "Alamouti" space-time code are used is as shown in FIG. 25.

In step 2401, the transmitting end of the MIMO system will have 8 of the serial signal streams to be transmitted (4N) The serial signal, for example, the signals XX ₂ , ... X ₈ , after serial-to-parallel conversion, obtains the corresponding 8 parallel signals, and the subsequent signals are equally converted every 8 to obtain a parallel signal stream. The present invention is applied to the transmission of a serial signal stream by serial transfer.

In step 2402, the eight parallel signals in the parallel signal stream are equally divided into two transform groups, for example, X ₂ , X ₃ and X ₄ are the first group, X ₅ , X ₆ , X ₇ and X ₈ For the second group.

In step 2403, the signals of the two transform groups are linearly transformed, and each transform group generates four transform results. Wherein, the signals of the first group, the transformation results of X ₂ , X ₃ and X ₄ are Sj, S ₃ , S ₅ and S ₇ ; the transformations of the signals of the second group X ₅ , X ₆ , X ₇ and X ₈ The results are S ₂ , S ₄ , S ₆ and S ₈ .

Wherein, the linear transformation performed may be an orthogonal transform, such as FFT, Hadamard transform or cosine transform.

In step 2404, the eight transformation results obtained by the signals of the two transformation groups are reorganized into two groups of four results groups.

S ₂ constitutes a first result set, S ₃ and S ₄ form a second result set, S ₅ and S ₆ form a third result set, and S ₇ and S ₈ form a fourth result set. The principle of recombination is that the two transformation results in each result group are required to come from different transformation groups.

In step 2405, the four result groups are respectively coded with a two-antenna space-time code of code rate 1, for example, "Alamouti" space-time code.

In step 2406, the four sets of transmit antennas respectively transmit the four sets of signals encoded by the two-antenna space-time code with a code rate of 1, wherein each of the two sets of antennas simultaneously transmits and continuously transmits two symbol symbols. When the "Alamouti" space-time code is used, the STC output by the eight transmitting antennas is as shown in FIG. 27 of the MIMO system according to the nineteenth embodiment of the present invention. When N = 2, 8 (4N) The transmitting antenna antenna 1 and the antenna 2 are a group, the antenna 3 and the antenna 4 are a group, the antenna 5. and the antenna 6 are a group, and the antenna 7 and the antenna 8 are a group, and the orthogonal transform and "Alamouti" are used. The STC scheme of the MIMO system at time and space code is as shown in FIG.

In step 2701, the transmitting end of the MIMO system serially converts 8 (4N) serial signals, for example, signals, X ₂ , ... X ₈ , of the serial signal stream to be transmitted. Corresponding 8 parallel signals, the subsequent signals are equally converted every 8 to obtain a parallel signal stream. The present invention is applied to the transmission of a serial signal stream by serial transfer. In step 2702, eight parallel signals in the parallel signal stream are linearly transformed to obtain eight transform results S ₂ , S ₃ , S ₄ , S ₅ , S ₆ , S ₇ and S ₈ .

In step 2703, the eight transformation results are equally divided into two transformation result groups, for example, S

S ₃ , S ₅ and S _{7 are} grouped into one group, and S ₂ , S ₄ , S ₆ and S _{8 are} divided into another group.

Steps 2704 to 2705 are similar to steps 2405 to 2406, respectively, and are not described here.

As shown in FIG. 29, the MIMO system signal transmitting apparatus according to the twentieth embodiment of the present invention includes 2N sets of antennas of 2 sets, 2N coding modules 2931, 2932 up to 293N corresponding to 2N sets of antennas, and Transform unit 2920, transform unit 2920 includes linear transform module 2921; further, the transmitting device further includes a serial-to-parallel module 2910, where N is an integer greater than zero.

Specifically, the serial to parallel module 2910 is configured to convert the serial signal stream to be transmitted into 4N parallel signal streams and output to the transform unit 2920. The linear transform module 2921 of the transform unit 2920 is configured to linearly transform 4N input parallel signals to be transmitted into 4N transform results, and output them to 2N encoding modules 2931, 2932 to 293N in two groups; each encoding module It is used to encode the input transform result with a dual antenna space-time code of code rate 1, for example, "Alamouti" space-time code, and output the coding result to the corresponding group of antennas; and the 2N group antennas are transmitted in turn from the corresponding coding module. The signal in which one set of encoded signals is transmitted simultaneously in each of the two sets of antennas every two symbol symbol times.

The linear transform may be an orthogonal transform, for example, an FFT, a Hadamard transform, or a cosine transform. The twenty-first embodiment of the present invention is a MIMO system receiving method in which four transmitting antennas and two receiving antennas, a code rate 2, and a transmitting end are encoded by an "Alamouti" space-time code, which can be used to receive the sixteenth and tenth tenth. The signal transmitted by the seven embodiments. Assuming that the channel parameters corresponding to the four transmit antennas and the two receive antennas are where T is the Tth transmit antenna and R is the Rth receive antenna, then the signals of the two receive antennas in the two symbol symbols can be expressed as: 2007/001572

-twenty three -

< ^r n = V; - Vi* + one ^s + "12

, ₂ 2

+ n ₂₂ ( n ) where is the received signal of the first receive antenna in the first symbol; is the received signal of the first receive antenna in the second symbol; is the second receive antenna at the first symbol The received signal in the second; is the received signal of the second receiving antenna in the second symbol;

For noise samples, assume a Gaussian distribution, zero mean and the same variance ^. The above formula can be further expressed as:

Assuming that the linear transformation of the transmitter (typically an orthogonal transformation) matrix is H _OT , we can get:

R = H _r „H _nr X + N ( ! ^

Estimated based on a minimum mean square error (Minimum mean-square error, said cartridge "MMSE") quasi-shell ¹ J receiver, the detection signal is:

^ = iHo _T Hc _H H _CH H _OT + ^Ι _η ) Ho _T H" _H R ( 14 ) Here, = is the signal to be detected, representing the estimated value of X; H _CH is the antenna

^ w:. The corresponding channel parameter matrix; H _OT is the linear transformation matrix of the transmitting end, for example, it can be an orthogonal transformation matrix, H^ represents the conjugate transposition of ^^; H^ represents the conjugate transposition of H _OT ; The superscript "-1" represents the inversion of the matrix. By the above method, it is possible to efficiently receive a full-diversity space-time code coded signal having a code rate of two.

A twenty-second embodiment of the present invention is a MIMO system signal receiving apparatus for encoding four transmit antennas and two receive antennas, a code rate of 2, and an "Alamouti" space-time code for a transmitting end, as shown in FIG. The signals transmitted by the sixteenth and seventeenth embodiments are received. The receiving device includes: two receiving antennas, a serial-to-parallel module 3010, a conjugate processing module 3021, a matrix calculation module 3022, and a matrix multiplication module 3023.

The serial rotation module 3021 is configured to convert the signal r _y in the 4N symbol symbols serially received by the antenna into a parallel received signal output, where r _y is the ith receiving antenna received in the symbol symbol j The signal, i=l, 2, l<j<4N, N is an integer greater than zero. For example, the signals r„, r _n , r ₁₃ , . . . and the signals r ₂₁ , r ₂₂ received by the antenna 2 are converted into four signals and output in parallel to obtain parallel received signals r„, r _{12 .} , r ₂₁ , r ₂₂ .

The conjugate processing module 3021 is configured to conjugate the r _y whose sequence number j is an even number in the parallel received signal from the serial-to-parallel module 3010, maintain the sequence number j as an odd number r3⁄4, and output the processing result as a vector R. For the parallel received signals r„, r _n , r , r ₂₂ , r ₁₂ and r _{22 are} conjugated, respectively

3⁄4 and .

Matrix calculation module _{3022 is} used to calculate and output the matrix

OT ^{x ±} CH

λ h 21 ^l 31 h '41 where H _ra is the channel parameter matrix corresponding to each antenna,

H, CH

^12 ^22 3⁄42 42 h 32 H _OT is the linear transformation matrix of the transmitting end, H, οτ H stands for H. OT total

The yoke is transposed, H^ represents the conjugate transpose of H _OT , σ,; represents the variance of the zero-mean Gaussian distribution noise, and the superscript represents the inverse of the matrix. The matrix multiplication module 3023 is used to multiply the matrix C by the vector R to obtain a detection result. In this embodiment, the conjugate processing module 3021, the matrix calculation module 3022, and the matrix multiplication module

The 3023 may constitute a signal recovery unit 3020 that restores the received signals detected within the respective symbol symbols to parallel signals.

The twenty-third embodiment of the present invention is a MIMO system receiving method in which eight transmitting antennas and two receiving antennas, a code rate of 2, and a transmitting end are encoded by an "Alamouti" space-time code, which can be used for receiving the eighteenth and tenth The signal transmitted by the nine embodiments. Assuming that the channel parameters corresponding to the eight transmit antennas and the two receive antennas are where T is the Tth transmit antenna and R is the Rth receive antenna, then the signals of the two receive antennas within the four symbol symbols can be expressed as:

r _n = h _ll s _l + h _2l s ₂ + h ₃₁ s ₃ + h ₄₁ s ₄ + n _n

= ^h 5\ ^S 5 + ^k 6l ^S 6 + ^71^7 + ^81^8 +

rU ⁼ ^5\ ^S 6 ~ ^6\ ^S 5 + ^7 8 — 1 7 + 14

Here is the received signal of the first receiving antenna in the kth symbol; the received signal of the second receiving antenna in the kth symbol; and the first receiving antenna and the receiving antenna respectively in the kth The noise sample values within the symbol are assumed to be Gaussian distribution, zero mean and same variance ^. The above formula can be further expressed as:

Assume that the linear transformation of the transmitter (typically orthogonal transform) matrix is H _OT , which can be obtained

R― Η _Γ ττΗ _ητ Χ + Ν (17)

The receiver based on the MMSE criterion detects the signal as

^ = [ ^H OT ^H CH ^H CH ^H OT ^{+ <T} n ^I n) ^ ^H OT ^H CH ^R (18)

Here, it is a signal to be detected, which represents an estimated value of X; H _OT is a channel parameter matrix corresponding to each antenna; H _OT is a linear transformation matrix of the transmitting end, for example, may be an orthogonal transformation matrix, and a conjugate transpose; H^ represents the conjugate transpose of H _OT ; the superscript represents the inversion of the matrix.

The twenty-fourth embodiment of the present invention is a receiving method in which 4N transmitting antennas and two receiving antennas and a transmitting end encode using an "Alamouti" space-time code. This embodiment adopts the ML algorithm, and calculates the corresponding ^ =(RH _CH H _OT X _k ) ^H (RH _CH H _OT X _k ) for each possible detection result; then, searches for the smallest among all The value, which is ₄ corresponding to the minimum value, is output as a detection result. In this way, it is possible to efficiently receive a full-diversity space-time code coded signal having a code rate of two. Rn r\,2N~\

Where the superscript 'Ή' represents the conjugate transpose operation on the matrix, ^r \, 2n

R I3⁄4 is the r2l

R2 2N-1

r ₂ . IN

The signals received by the receiving antenna in the symbol symbol j, i=l, 2, l<j<4N, N is greater than 0

The number, * represents the conjugate of r _y , X is the required number, and H _ffl is the corresponding to each antenna

a channel parameter matrix, H _OT is a linear transformation matrix at the transmitting end, for example, an orthogonal transformation matrix,

When the number of transmitting antennas is 4, H _CH =

κ Κ 0 0 0 0

0 0 0 0 κ h 〃32 0 0 0 0 When the number of transmitting antennas is 8, "22 Κι -Κι 0 0 0 0

Η _σΗ =

Κ

Receive

The channel parameter corresponding to antenna i. The twenty-fifth embodiment of the present invention is a signal receiving apparatus for a MIMO system in which four transmitting antennas and two receiving antennas, a code rate 2, and a transmitting end are encoded by an "Alamouti" space-time code, as shown in FIG. 31, Two receiving antennas, a serial to parallel module 3110, a conjugate processing module 3121, and an ML algorithm module 3122.

The serial rotation module 3110 is configured to convert the signal 126 in the 4N symbol symbols serially received by the antenna into a parallel received signal output, where ry is the signal received by the ith receiving antenna in the symbol symbol j. , i = l, 2, l ≤ j ≤ 4N, where N is an integer greater than zero. For example, when N = l, it indicates that the transmitting end is four transmitting antennas, and the signals r„, r _n , r ₁₃ , ... received from the receiving antenna 1 and the signals r ₂₁ , r ₂₂ received from the receiving antenna 2 are ,..., converted into 4 signals in parallel to obtain parallel received signals ^ r _u , r ₂ r ₂₂ .

The conjugate processing module 3121 is configured to sequence the parallel received signals from the serial to parallel module 3110 The y whose number j is an even number is conjugated, and the number j is maintained as an odd number, and the processing result is output as a vector R. For the parallel received signals r„, r _n , r _2l , r ₂₂ , the conjugate is summed with 3⁄4, respectively

3⁄4 and .

ML algorithm module 3122 for calculating its corresponding detection result for each possible _{_{Z k = (R - H CH}} H 0T X k) H (R -H CH H 0T X k), the search of all the Z _ft The minimum value, X _k corresponding to the minimum value is output as a detection result. Where H _OT is the channel parameter matrix corresponding to each antenna, H _CH

w„ w ₁₂ w ₁₃ w _u

w ₂₁ w ₂₂ w ₂₃ w _u

H _OT is the linear transformation matrix of the transmitting end, H. _T = , the superscript ' Ή ' stands for the moment w ₃₁ w ₃₂ w ₃₃ w ₃₄

w ₄₁ w ₄₂ w ₄₃ w The _44- frame conjugate transpose operation.

In this embodiment, the conjugate processing module 3121 and the ML algorithm module 3122 may constitute a signal recovery unit 3120, and restore the received signals detected in the respective symbol symbols to parallel signals.

A person skilled in the art can understand that all or part of the steps in implementing the above method embodiments can be completed by a program to instruct related hardware, and the program can be stored in a computer readable storage medium, and the program is executed. All or part of the steps in the above method embodiments may be included. The storage medium may be a read only memory, a random access memory, a magnetic disk, an optical disk, or the like.

In the embodiment of the present invention, 2KM signals to be transmitted are transmitted by the KM to the antenna after linear conversion and dual antenna space-time code encoding with a code rate of 1, so each signal is transmitted via 2KM antennas, and has 2KM signals. The full diversity effect of the antenna, the transmission performance is better; and the transmission is performed in units of K to the antenna, and the code rate is not less than 1.

Although the invention has been illustrated and described with reference to the preferred embodiments of the present invention, it will be understood The spirit and scope of the invention.

Claims

Rights request

A signal transmission method for a multiple input multiple output system, wherein a transmitting signal is transmitted by two groups of KM group antennas, wherein K and Μ are integers greater than 0 and ΚΜ>1; wherein the method comprises :

The transmitting method according to claim 1, wherein the obtaining 2KM transform results by the 2KM parallel signals to be sent includes:

Dividing 2KM parallel signals into two transform groups, each group of KM signals;

Linearly transforming KM signals in each transform group;

The recombination of 2KM transformation results into KM result groups includes: 2KM transformation results are reorganized into KM result groups in groups of two, and two transformation results in each result group are from different transformation groups.

The transmitting method according to claim 1, wherein the obtaining 2KM transform results by the 2KM parallel signals to be transmitted comprises: linearly transforming 2KM parallel signals.

The transmission method according to any one of claims 1 to 3, characterized in that the linear transformation is orthogonal transformation.

The transmitting method according to any one of claims 1 to 3, characterized in that: the dual antenna space-time code with a code rate of 1 is an Alamouti space-time code.

The transmitting method according to claim 1, wherein the transmitting of the K sets of antennas comprises: transmitting the K sets of the encoded signals simultaneously through the K sets of antennas, wherein the two symbol symbols are One result set of encoded signals is transmitted in each set of antennas during the time.

7. The transmitting method according to claim 1, wherein the method further comprises: converting 2KM serial signals in the serial signal stream into 2KM parallel signals to be transmitted.

8. A multi-input multi-output system signal transmitting apparatus, characterized in that it comprises two a group of KM group antennas, KM coding modules and transform units corresponding to each group of antennas, wherein K, Μ are integers greater than 0 and ΚΜ>1, where:

a transform unit, configured to obtain 2 transform results from 2 parallel signals to be transmitted by linear transform, and output to 1 coding module as 2 sets of 2 transform results; 2 transform results in each group include 2 parallel a linear combination of signals;

KM coding modules, which are used to encode the input two conversion results by a random antenna space-time code with a code rate of 1;

9. The transmitting apparatus according to claim 8, wherein: the transforming unit comprises two linear transform modules, each linear transform module is configured to linearly transform KM parallel signals to obtain KM transform results, and The transformation results are output to KM coding modules respectively.

10. The transmitting apparatus according to claim 8, wherein: the transforming unit comprises a linear transforming module, configured to perform linear transformation on 2KM parallel signals to obtain 2KM transform results, and to perform two transforms. As a result, one group is output to KM coding modules, respectively.

The transmitting apparatus according to claim 9 or 10, wherein the linear transform module is an orthogonal transform module.

12. The transmitting apparatus according to claim 8, wherein: the double-sky line space-time code having a code rate of 1 is an Alamouti space-time code.

13. The transmitting apparatus according to claim 8, wherein: the apparatus further comprises a serial transfer module for converting 2KM serial signals in the serial signal stream into 2KM parallel signals to be transmitted.

A signal receiving method for a multiple input multiple output system, wherein the signal is transmitted by two groups of KM group antennas, wherein K is the number of antenna groups simultaneously transmitted, K, Μ is an integer greater than 0 and ΚΜ >1; The number of receiving antennas is not less than Κ; characterized in that the method comprises:

Detecting 2 received signals in 2 symbol symbols;

The receiving method according to claim 14, wherein the receiving is performed by two The signal obtains 2KM parallel signals, which are: a minimum mean square error estimation MMSE criterion, and 2KM parallel signals are calculated from the 2M received signals and a linear transformation matrix before transmission and a dual antenna space-time code with a code rate of 1. .

The receiving method according to claim 15, wherein: the antenna space-time code of the code rate 1 is an Alamouti space-time code;

The calculation of 2KM parallel signals according to the MMSE criterion is performed according to the following formula:

X

Valuation

^ is the received signal of the pth receiving antenna in q symbol symbols, l ≤ p < K, l ≤ g ≤ 2M, on

H _U 0 0

0 H

Mark * indicates conjugate; 22 0

H, CH is the channel reference corresponding to the transmitting antenna and the receiving antenna.

0 0 Η MM

Number of rebellion, in the formula H, , 0≤ < , h _ab

Showing the channel state corresponding to the a-th transmitting antenna and the b-th receiving antenna; being a diagonal unit matrix; ^ the variance of the zero-mean Gaussian distribution noise; the superscript H indicating the conjugate transposition operation of the matrix; Represents the inversion of a matrix.

The receiving method according to claim 14, wherein the obtaining 2KM parallel signals from 2KM received signals is: using a maximum likelihood ML algorithm, according to the 2KM received signals and before transmitting A linear transformation matrix and a two-antenna space-time code with a code rate of 1 determine 2KM parallel signals.

The receiving method according to claim 17, wherein: the dual antenna space-time code with a code rate of 1 is an Alamouti space-time code;

The determining the 2KM parallel signals by using the ML algorithm includes:

For each possible value of 2KM parallel signals, calculate

One of Z _k

Array

Ri, 2M

R = r _pq is the received signal of the pth receiving antenna in q symbol symbols, l ≤ _P ≤ K

r K, 1M

0

0 H. 0

l≤q≤2M, superscript * indicates conjugate; 22

H _CH = is the transmitting antenna and receiving antenna

0 0 H MM ^2/^+2,1 ' ^ri 2iK+2K-l,\

― / 2,l /X+U · · · — , X+2人', 1 ^2iK+2K- , \ corresponding channel parameter matrix, where

^2iK+2K, K one

0 ≤ i < M , indicating the channel state corresponding to the a-th transmitting antenna and the b-th receiving antenna;

Η matrix conjugate transpose operation; Find the minimum of all [zeta] _[alpha], which is the minimum value of _t corresponding to 2KM parallel signals.

The receiving method according to claim 16 or 18, wherein the H _OT is an orthogonal matrix.

The receiving method according to claim 14, wherein when K=l, obtaining the two parallel signals from the two received signals comprises:

Decoding two received signals in each of the two symbol symbols according to the dual antenna space-time code of the code rate of 1;

According to the linear transformation performed before the transmission, two parallel signals are obtained from the decoding result of the order.

The receiving method according to claim 20, wherein: the linear transformation performed before the transmission is a linear transformation performed on two sets of each of the parallel signals;

The obtaining of 2 parallel signals by the decoding result of the order includes:

The two decoding results obtained by decoding one time are divided into two groups, and the decoding results in each group are respectively obtained from the decoding;

A linear inverse transform is performed on the decoding results of each of the sets to obtain two parallel signals, which corresponds to the linear transformation performed by the pre-transmission packet.

22. The receiving method according to claim 21, wherein: the linear transformation performed before the transmission is a linear transformation performed on two parallel signals;

The obtaining of the two parallel signals by the decoding result of the order includes: performing inverse transform of the linear transform before transmission on the two decoding results, and obtaining two parallel signals.

The receiving method according to claim 21 or 22, wherein the linear inversion is changed to an orthogonal transform.

The receiving method according to claim 14, wherein the method further comprises: Converting the 2KM parallel signals into a serial signal stream.

25. A multiple input multiple output system signal receiving apparatus, wherein the signal is transmitted by two groups of KM group antennas, wherein K is the number of antenna groups simultaneously transmitted, K, Μ is an integer greater than 0 and ΚΜ The device includes at least one receiving antenna, and the device further includes: a serial-to-parallel module, configured to convert two consecutive received signals detected by the receiving antenna into two parallel symbol symbols into parallel The received signal is output to the signal recovery unit;

The receiving apparatus according to claim 25, wherein the dual antenna space-time code having a code rate of 1 is an Alamouti space-time code.

The receiving device according to claim 26, wherein the signal processing unit comprises:

The conjugate processing module is configured to conjugate the received signal with an even number of the 2KM received signals from the serial-to-parallel module, and maintain the received signal with the odd-numbered sequence unchanged, and use the processing result as a vector

Ri, 2M

R output, where is the received signal of the pth receive antenna in q symbol symbols: rK, 2

K, 2M~\

r

l≤p≤K , \≤q≤2M , superscript * indicates conjugate; matrix calculation module, where J„

a diagonal unit matrix; Η _οτ matrix;

Corresponding channel parameter matrix, where

0 < z < , Λ. ₄ indicates the first hair

The channel state corresponding to the transmit antenna and the bth receive antenna; the variance of the zero mean Gaussian distribution noise; the superscript H represents the conjugate transpose operation of the matrix; the superscript -1 represents the inverse operation of the matrix.

A matrix multiplication module is used to multiply the matrix C by the vector ? output of the conjugate processing module to obtain 2KM parallel signals.

The receiving device according to claim 26, wherein the signal recovery unit comprises:

r\,2M-\

r\,2M

R = output, where is the received signal of the pth receive antenna in q symbol symbols: rK, 2 rK, 2M-\

rK, 2M

l≤p≤K , \ < q≤2M , superscript * indicates total

ML algorithm module, for each possible value of 2KM parallel signals; ^ calculating its Z, corresponding to the minimum value of ^; ^ obtaining 2KM parallel signals; the calculation according to the following formula: Z,

12 2KM

W ₀₁ W 2.2 _t 2KM

Possible value; is the linear transformation matrix before transmission

^W 2KMA ^W 2KM: 2ΚΜΛΚΜ rn r\,lM-\

r\,2M

R r _pq is the received signal of the pth receiving antenna in q symbol symbols, ί ≤ ρ ≤ Κ

rK, 2M-l

rK, 2M

H _u 0 0

0 H

Total 22 0

l≤q≤2M, the superscript * indicates that H _CH = is the transmitting antenna and the receiving antenna

0 0 H MM , a corresponding channel parameter matrix, where H,

0 ≤ i < M , ₄ represents the channel state corresponding to the a-th transmitting antenna and the b-th receiving antenna;

H is the conjugate transpose operation of the matrix.

The receiving device according to claim 27 or 28, wherein: ^ is a quadrature matrix.

30. The receiving device according to claim 25, wherein the device further comprises The serial module is used to convert 2KM parallel signals into serial signal streams.

31. A multiple input multiple output system signal receiving apparatus, wherein said signal is transmitted in turn using two N sets of antennas, wherein N is an integer greater than one; said apparatus comprising at least one receive antenna, characterized The device further includes:

The signal inverse transform unit is configured to obtain 2N parallel signals from the 2N decoded results of the N decodings according to the linear transform performed before the reception of the received signal.

The receiving apparatus according to claim 31, wherein: the linear transformation performed before the transmission of the received signal is a linear transformation performed on two sets of each of the M parallel signals;

The inverse signal transform unit includes two linear transform modules, each linear transform module is configured to perform linear inverse transform on N decoding results respectively from N decodings to obtain N parallel signals, where the inverse transforms respectively correspond to the sending The linear transformation performed before the two groups.

33. The receiving apparatus according to claim 31, wherein: the linear transformation performed before the transmission is a linear transformation performed on 2M parallel signals;

The signal inverse transform unit includes a linear transform module for performing inverse transform of the linear transform before the received signal transmission on the 2N decoding results to obtain 2N parallel signals.

The receiving apparatus according to claim 32 or 33, wherein the linear inversion is changed to an orthogonal transform.

The receiving apparatus according to claim 31, wherein the method further comprises: converting the 2KM parallel signals into a serial signal stream.