CN101997649A - Method and device for processing MU-MIMO (Multiuser Multiple-Input Multiple-Output) based on orthogonal diversity - Google Patents

Abstract

The invention discloses a multi-user multiple-input multiple-output (MU-MIMO) processing method based on orthogonal diversity, which includes: mapping data streams of different users to empty space through independent layering and specific orthogonal diversity precoding In the matrix of frequency coding; the data of different users in the matrix of space frequency coding are respectively subjected to multi-user precoding or beamforming (BF) processing, and the processed data are resource-mapped and then transmitted through the transmitting antenna. The invention also discloses a MU-MIMO processing device based on orthogonal diversity. Through the method and device of the present invention, multi-user transmit diversity processing is realized, antenna and carrier resources are fully utilized, and more users can be multiplexed under the same resource consumption.

Description

A MU-MIMO processing method and device based on orthogonal diversity

technical field

The present invention relates to the transmit diversity technology in the Long Term Evolution (LTE, Long Term Evolution) system, in particular to a multi-user multiple input multiple output (MU--MIMO, Multiple User Multiple Input Multiple Output) processing method and device based on orthogonal diversity .

Background technique

In the LTE system, the downlink defines that the diversity method when the transmitting antenna is 2 antennas is space-frequency coding (SFBC, Space-Frequency Block Codes), and the coding matrix is as follows:

和

分别表示S₁和S₂的共轭。In the above formula, each row of the matrix corresponds to a different transmission frequency, and each column of the matrix corresponds to a different transmission antenna; S ₁ represents the data mapped to subcarrier (Subcarrier) 1 at the first moment, and S ₂ represents the data mapped to Subcarrier 2 at the second moment The data,

and

denote the conjugations of _S1 and _S2 , respectively.

When the transmitting antenna is 4 antennas, the diversity method is SFBC+Frequency Switching Transmit Diversity (FSTD, FrequencySwitching Transmit Diversity), and the encoding matrix is as follows:

和分别表示S₁、S₂、S₃和S₄的共轭。In the above formula, each row of the matrix corresponds to a different transmission frequency, and each column of the matrix corresponds to a different transmission antenna; S ₁ represents the data mapped to Subcarrier 1 at the first moment, S ₂ represents the data mapped to Subcarrier 2 at the second moment, and S ₃ indicates the data mapped to Subcarrier 3 at the third moment, S ₄ indicates the data mapped to Subcarrier 4 at the fourth moment,

and denote the conjugates of S ₁ , S ₂ , S ₃ and S ₄ , respectively.

In the existing version of LTE, the antenna and carrier resources are not fully utilized when the 4-antenna is transmitted, and only a single-user transmit diversity scheme is adopted, and multi-user orthogonal diversity multiplexing is not involved, thereby limiting the performance of LTE.

Contents of the invention

In view of this, the main purpose of the present invention is to provide a MU-MIMO processing method and device based on orthogonal diversity, so as to realize transmit diversity processing of multiple users.

In order to achieve the above object, technical solution of the present invention is achieved in that way:

The present invention provides a multi-user multiple-input multiple-output MU-MIMO processing method based on orthogonal diversity, the method comprising:

The data streams of different users are mapped to the space-frequency coded matrix through independent layering and specific orthogonal diversity precoding;

Perform multi-user precoding or beamforming BF processing on the data of different users in the space-frequency coding matrix, and transmit the processed data through the transmitting antenna after resource mapping.

The method further includes: when the number of transmit antennas is greater than or equal to 8, the specific orthogonal diversity precoding matrix is:

$\left[\begin{array}{cccc}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; three</span>}}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}^{<span\; class="notranslate">\; *</span>}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; four</span>}}^{<span\; class="notranslate">\; *</span>}\\ {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; four</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; three</span>}}^{<span\; class="notranslate">\; *</span>}\\ {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 13</span>}}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}^{<span\; class="notranslate">\; *</span>}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 14</span>}}^{<span\; class="notranslate">\; *</span>}\\ {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 14</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 13</span>}}^{<span\; class="notranslate">\; *</span>}\end{array}\right]$

Among them, S _1i represents the data sent by user 1, S _2i represents the data sent by user 2, i=1, 2, 3, 4;

The data stream for user 1 is mapped to the space-frequency coded matrix through hierarchical and diversity precoding, and the data stream for user 2 is mapped to the space-frequency coded matrix through the complementary diversity precoding matrix.

The method further includes: when the number of transmit antennas is greater than or equal to 8, the specific orthogonal diversity precoding matrix is:

$\left[\begin{array}{cccc}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; three</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; four</span>}}\\ <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}^{<span\; class="notranslate">\; *</span>}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; four</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; three</span>}}^{<span\; class="notranslate">\; *</span>}\\ {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 13</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 14</span>}}\\ <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}^{<span\; class="notranslate">\; *</span>}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 14</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 13</span>}}^{<span\; class="notranslate">\; *</span>}\end{array}\right]$

Among them, S _1i represents the data sent by user 1, S _2i represents the data sent by user 2, i=1, 2, 3, 4;

The data stream for user 1 is mapped to the space-frequency coded matrix through hierarchical and diversity precoding, and the data stream for user 2 is mapped to the space-frequency coded matrix through the complementary diversity precoding matrix.

The method further includes: when the number of transmit antennas is greater than or equal to 8, the specific orthogonal diversity precoding matrix is:

$\left[\begin{array}{cccc}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 13</span>}}^{<span\; class="notranslate">\; *</span>}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 14</span>}}^{<span\; class="notranslate">\; *</span>}\\ <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 14</span>}}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 13</span>}}\\ {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 13</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 14</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}^{<span\; class="notranslate">\; *</span>}\\ <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 14</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 13</span>}}^{<span\; class="notranslate">\; *</span>}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}\end{array}\right]<span\; class="notranslate">\; ,</span>\left[\begin{array}{cccc}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; three</span>}}^{<span\; class="notranslate">\; *</span>}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; four</span>}}^{<span\; class="notranslate">\; *</span>}\\ <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; four</span>}}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; three</span>}}\\ {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; three</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; four</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}^{<span\; class="notranslate">\; *</span>}\\ <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; four</span>}}^{<span\; class="notranslate">\; *</span>}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; three</span>}}^{<span\; class="notranslate">\; *</span>}& <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}& {\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}\end{array}\right]$

Among them, S _1i represents the data sent by user 1, S _2i represents the data sent by user 2, i=1, 2, 3, 4;

The data stream for user 1 is mapped to the space-frequency coded matrix through hierarchical and diversity precoding, and the data stream for user 2 is mapped to the space-frequency coded matrix through the same diversity precoding matrix as user 1.

The multi-user precoding or BF processing is specifically:

The data of different users in the space-frequency coded matrix are respectively multiplied by different precoding vectors, or by different BF vectors.

The present invention also provides a MU-MIMO processing device based on orthogonal diversity, which includes:

The orthogonal diversity precoding module is used to map the data streams of different users into the space-frequency coding matrix through layered and specific orthogonal diversity precoding;

A multi-user precoding module, configured to perform multi-user precoding or BF processing on the data of different users in the matrix of the space-frequency coding;

The transmitting module is configured to transmit the data processed by the multi-user precoding module after resource mapping.

When the number of transmit antennas is greater than or equal to 8, the orthogonal diversity precoding module is further used to map the data stream of user 1 into a space-frequency coded matrix through hierarchical and diversity precoding, and map the data stream of user 2 Then, the complementary diversity precoding matrix is mapped to the space-frequency coding matrix.

When the number of transmit antennas is greater than or equal to 8, the orthogonal diversity precoding module is further used to map the data stream of user 1 into a space-frequency coded matrix through hierarchical and diversity precoding, and map the data stream of user 2 Then, the same diversity precoding matrix as that of user 1 is used to map to the space-frequency coding matrix.

The multi-user precoding module is further configured to multiply data of different users in the space-frequency coded matrix by different precoding vectors, or by different BF vectors.

In the MU-MIMO processing method and device based on orthogonal diversity provided by the present invention, the data streams of different users are mapped to the space-frequency coded matrix through independent layering and specific orthogonal diversity precoding; and then Multi-user precoding or beamforming (BF) processing is performed on the data of different users respectively, and the processed data is transmitted outside after resource mapping. The present invention makes full use of antenna and carrier resources through multi-user orthogonal diversity multiplexing, and multiplexes more users under the same resource consumption; without adding additional pilot overhead, better The performance gain; the use of precoding and BF technology eliminates the interference between multiple users, and increases the diversity gain for a single user.

Description of drawings

Fig. 1 is a flow chart of an MU-MIMO processing method based on orthogonal diversity in the present invention;

FIG. 2 is a schematic diagram of MU-MIMO processing based on orthogonal diversity in an embodiment of the present invention;

FIG. 3 is a schematic diagram of the composition and structure of an MU-MIMO processing device based on orthogonal diversity according to the present invention.

Detailed ways

The technical solutions of the present invention will be further elaborated below in conjunction with the accompanying drawings and specific embodiments.

A kind of MU-MIMO processing method based on orthogonal diversity provided by the present invention, as shown in Figure 1, mainly comprises the following steps:

In step 101, the base station maps data streams of different users into a space-frequency coded matrix through independent layering and specific orthogonal diversity precoding.

Step 102, perform multi-user precoding or beamforming (BF, Beamforming) processing on the data of different users in the space-frequency coded matrix respectively.

Specifically, the data of different users in the space-frequency coding matrix are respectively multiplied by different precoding vectors, or by different BF vectors. Moreover, the precoding vector or the BF vector can be calculated according to the interchangeability between the uplink and downlink channels, or according to the information feedback from the uplink channel to the downlink channel.

Step 103, the processed data is resource-mapped and then transmitted through the transmitting antenna.

S1和S2为编码前的符号，通过Alamouti编码后行对应相邻时刻或者相邻频率，列代表不同的发射天线。此外，在SFBC下利用预编码技术能消除多用户之间的干扰，而且可以通过选择最佳的预编码矢量使得分集性能得到进一步的增强。因此本发明结合预编码波束形成和发射分集，设计LTE-Advanced系统的多用户分集方法。At present, it has been proved by theoretical analysis and simulation verification that sending the diversity output signals into independent beamforming arrays can obtain a gain of 6dB compared with Alamouti diversity, where the coding matrix of Alamouti diversity is

S1 and S2 are the symbols before encoding. After Alamouti encoding, the rows correspond to adjacent times or adjacent frequencies, and the columns represent different transmitting antennas. In addition, the use of precoding technology under SFBC can eliminate the interference between multiple users, and the diversity performance can be further enhanced by selecting the best precoding vector. Therefore, the present invention combines precoding beamforming and transmit diversity to design a multi-user diversity method for an LTE-Advanced system.

Among them, the corresponding relationship in the diversity method in which the transmitting antenna is 4 antennas is:

用户1Subcarrier

user 1

用户2Subcarrier

user 2

S _1i is data sent by user 1, S _2i is data sent by user 2, i=1, 2, 3, 4.

The corresponding relationship in the diversity method with 8 transmitting antennas is:

用户1Subcarrier

user 1

用户2Subcarrier

user 2

Subcarrier $\left[\begin{array}{cccc}{S}_{11}& S_{\mathrm{twenty\; three}}& -S_{12}^{*}& -S_{\mathrm{twenty\; four}}^{*}\\ S_{12}& S_{\mathrm{twenty\; four}}& S_{11}^{*}& S_{\mathrm{twenty\; three}}^{*}\\ S_{\mathrm{twenty\; one}}& S_{13}& -S_{\mathrm{twenty\; two}}^{*}& -S_{14}^{*}\\ S_{\mathrm{twenty\; two}}& S_{14}& S_{\mathrm{twenty\; one}}^{*}& S_{13}^{*}\end{array}\right]$

In the case of 8 antennas, a maximum of 4 users can be multiplexed by using two-antenna space-frequency coding. When using the coding method of 8 antennas, the precoding vector can not only eliminate multi-user interference, but also enhance the signal energy of users.

When the transmitting antenna is extended to N (N ≥ 8) antennas, the corresponding relationship in the corresponding diversity method is:

用户1Subcarrier

user 1

Subcarrier user 2

用户N/2Subcarrier

User N/2

Subcarrier $\left[\begin{array}{cccc}{S}_{11}& S_{\mathrm{twenty\; three}}& -S_{12}^{*}& -S_{\mathrm{twenty\; four}}^{*}\\ S_{12}& S_{\mathrm{twenty\; four}}& S_{11}^{*}& S_{\mathrm{twenty\; three}}^{*}\\ S_{\mathrm{twenty\; one}}& S_{13}& -S_{\mathrm{twenty\; two}}^{*}& -S_{14}^{*}\\ S_{\mathrm{twenty\; two}}& S_{14}& S_{\mathrm{twenty\; one}}^{*}& S_{13}^{*}\end{array}\right]$

Wherein, S _ni is data sent by user n, n=1, 2, 3, . . . , N/2, i=1, 2, 3, 4. In the case of N antennas, a maximum of N/2 users can be multiplexed by using two-antenna space-frequency coding. When the number of users is less than N/2, the encoding method when N antennas are used, the precoding vector can not only eliminate multi-user interference, but also enhance the signal energy of users.

Based on the schematic diagram of MU-MIMO processing shown in FIG. 2 , the above MU-MIMO processing method is further described in detail in combination with specific embodiments.

Embodiment 1: 4-antenna multi-user 2-antenna diversity coding matrix is as follows:

用户1Subcarrier

user 1

用户2Subcarrier

user 2

Divide the two streams of different users (the data stream of user 1 and the data stream of user 2) into two layers respectively, perform orthogonal diversity precoding respectively, and then multiply different precoding vectors or BF for different users Vector, and then transmit user data through the actual antenna after resource mapping.

The precoding vector or BF vector here is on the one hand to eliminate the interference between multiple users, that is, through zero forcing (ZF, Zero Forcing), block diagonalization (BD, Block Diagnolization) and Tomlinson-Halashi Tomlinson-Harashima Precoding (THP, Tomlinson-Harashima Precoding) and other methods, or through multi-user weighted vector pairing criteria to perform interference cancellation; on the other hand, in order to enhance the diversity gain of each user, the maximum signal interference based on eigenvalue decomposition Noise ratio (SINR, Signal to InterferencNoise Ratio) criterion to calculate the weighted vector.

In the case of an open loop, use the interchangeability of the channel and calculate the downlink channel correlation matrix by estimating the uplink channel correlation matrix to determine the vector pairing of multiple users; or use the uplink ePlus link to calculate the wave Angle of Arrival (AOA, Angle of Arrival) determines the BF vector of each user, and selects two users with the largest angle difference between the two users (the BF vectors are orthogonal). In the case of a closed loop, two users with orthogonal precoding vectors can be selected for pairing by feeding back the precoding codebook index (PMI, Precoding Matrix Index), or feedback channel information (H _i ), and use ZF or BD, The THP algorithm realizes the interference elimination between multiple users, and can also feed back the autocorrelation matrix of the matrix, and use the user pairing algorithm to realize the pairing between two users.

Embodiment 2: 8-antenna multi-user 2-antenna diversity coding matrix is as follows:

用户1Subcarrier

user 1

Subcarrier user 2

用户3Subcarrier

user 3

用户4Subcarrier

user 4

When multiplexing 4 users in the case of 8 antennas, first map the streams of the first two users to four layers, then map the streams of the last two users to the other four layers, and then perform orthogonal diversity pre-processing Coding, and then multiplied by different precoding vectors or BF vectors for different users, and finally through resource mapping (mapped to the same time-frequency resource) and then sent out through the actual antenna. The calculation method of the precoding vector or the BF vector is the same as that in the first embodiment.

It should be pointed out that when the channel information is PMI or Rank Index (RI, Rank Index), the pairing method of Signal to Leakage Noise Ratio (SLNR, Signal to LeakageNoise Ratio) can be used when there is no optimal orthogonal weight vector. When multiplexing fewer users in the case of 8 antennas, the precoding vector can not only eliminate multi-user interference, but also enhance the signal energy of users.

Embodiment 3: 8-antenna multi-user 4-antenna diversity coding matrix:

Subcarrier $\left[\begin{array}{cccc}{S}_{11}& S_{\mathrm{twenty\; three}}& -S_{12}^{*}& -S_{\mathrm{twenty\; four}}^{*}\\ S_{12}& S_{\mathrm{twenty\; four}}& S_{11}^{*}& S_{\mathrm{twenty\; three}}^{*}\\ S_{\mathrm{twenty\; one}}& S_{13}& -S_{\mathrm{twenty\; two}}^{*}& -S_{14}^{*}\\ S_{\mathrm{twenty\; two}}& S_{14}& S_{\mathrm{twenty\; one}}^{*}& S_{13}^{*}\end{array}\right]$

User 1 maps the modulation symbols to the space-frequency coding matrix through hierarchical and diversity precoding, and user 2 uses the complementary diversity precoding matrix to map the modulation symbols to the space-frequency coding matrix, and then users 1 and 2 respectively perform multi-user Precoding or BF processing, and finally through resource mapping and then sent out through the actual antenna. Using 8-antenna diversity can obtain better diversity gain, and using 8-antenna BF can not only eliminate multi-user interference, but also enhance user signal energy. The specific calculation of the precoding vector or the BF vector is as described in the first embodiment.

Embodiment 4: 8-antenna multi-user 4-antenna diversity coding matrix:

Subcarrier $\left[\begin{array}{cccc}{S}_{11}& S_{12}& S_{\mathrm{twenty\; three}}& S_{\mathrm{twenty\; four}}\\ -S_{12}^{*}& S_{11}^{*}& -S_{\mathrm{twenty\; four}}^{*}& S_{\mathrm{twenty\; three}}^{*}\\ S_{\mathrm{twenty\; one}}& S_{\mathrm{twenty\; two}}& S_{13}& S_{14}\\ -S_{\mathrm{twenty\; two}}^{*}& S_{\mathrm{twenty\; one}}^{*}& -S_{14}^{*}& S_{13}^{*}\end{array}\right]$

User 1 maps the modulation symbols to the space-frequency coding matrix through hierarchical and diversity precoding, and user 2 uses the complementary diversity precoding matrix to map the modulation symbols to the space-frequency coding matrix, and then users 1 and 2 respectively perform multi-user Precoding or BF processing, and finally through resource mapping and then sent out through the actual antenna. The difference from the third example lies in the difference of the diversity precoding matrix. The specific calculation of the precoding vector or the BF vector is as described in the first embodiment.

Embodiment 5: 8-antenna multi-user 4-antenna diversity coding matrix:

用户1Subcarrier

user 1

用户2Subcarrier

user 2

User 1 maps the modulation symbols to the space-frequency coding matrix through layered and diversity precoding, and user 2 uses the same diversity precoding matrix to map the modulation symbols to the space-frequency coding matrix, and then users 1 and 2 perform multi-user Precoding or BF processing, and finally through resource mapping (multiple users occupy exactly the same resource) and then sent out through the actual antenna. The difference from the previous example lies in the difference of the diversity precoding matrix. This precoding matrix can provide better diversity gain. The specific calculation of the precoding vector or the BF vector is as described in the first embodiment.

In order to realize the above-mentioned MU-MIMO processing method based on orthogonal diversity, the present invention also provides an MU-MIMO processing device based on orthogonal diversity, as shown in FIG. 3 , the device includes: an orthogonal diversity precoding module 10, A multi-user precoding module 20 and a transmitting module 30 . The orthogonal diversity precoding module 10 is configured to map data streams of different users into a space-frequency coding matrix through layered and specific orthogonal diversity precoding. The multi-user precoding module 20 is used to perform multi-user precoding or BF processing on the data of different users in the space-frequency coded matrix, specifically: multiply the data of different users in the space-frequency coded matrix by different The precoding vector of , or multiplied by a different BF vector. The transmitting module 30 is configured to transmit the data processed by the multi-user precoding module 20 after resource mapping.

The multi-user precoding module 20 can calculate the precoding vector or the BF vector according to the interchangeability between the uplink and downlink channels, or according to the information feedback from the uplink channel to the downlink channel. In the case of an open loop, the interchangeability of the channel can be used, and the downlink channel correlation matrix can be calculated by estimating the uplink channel correlation matrix to determine the vector pairing of multiple users; or the uplink can be used to calculate AOA to Determine the BF vector for each user. In the case of a closed loop, two users with orthogonal precoding vectors are selected for pairing by feeding back PMI; or by feeding back channel information Hi, and using ZF or BD, THP algorithms to perform interference cancellation between multiple users; or by feedback matrix autocorrelation matrix, and utilizes the user's pairing algorithm to perform pairing between two users.

When the number of transmit antennas is greater than or equal to 8, the orthogonal diversity precoding module 10 is further configured to map the data stream of user 1 into a space-frequency coded matrix through layered and diversity precoding, and the data stream of user 2 The complementary or the same diversity precoding matrix is mapped to the space-frequency coding matrix.

It should be pointed out that the SFBC coding scheme adopted in the present invention can have various modifications, so the orthogonal space-frequency or space-time coding units can replace the SFBC and SFBC+FSTD coding schemes in this paper, and all should include the present invention within the scope of protection.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention.

Claims (9)

1. multi-user's multiple-input and multiple-output MU-MIMO processing method based on orthogonal set is characterized in that this method comprises:

Data flow to different user is passed through independently layering and specific orthogonal set precoding, is mapped in the matrix of space-frequency coding;

The data of different user in the described space-frequency coding matrix are carried out multi-user pre-coding or beam shaping BF processing respectively, and the data after will handling are outwards launched by transmitting antenna after the resource mapping.

2. according to the described MU-MIMO processing method of claim 1, it is characterized in that this method further comprises based on orthogonal set: when number of transmit antennas more than or equal to 8 the time, the matrix of described specific orthogonal set precoding is:

$\left[\begin{array}{cccc}{S}_{11}& S_{23}& -S_{12}^{*}& -S_{24}^{*}\\ S_{12}& S_{24}& S_{11}^{*}& S_{23}^{*}\\ S_{21}& S_{13}& -S_{22}^{*}& -S_{14}^{*}\\ S_{22}& S_{14}& S_{21}^{*}& S_{13}^{*}\end{array}\right]$

Wherein, S _1iThe data that expression user 1 sends, S _2iThe data that expression user 2 sends, i=1,2,3,4;

Data flow to user 1 is mapped in the matrix of space-frequency coding by layering and diversity precoding, and user 2 data flow then is mapped in the matrix of space-frequency coding by the diversity pre-coding matrix of complementation.

3. according to the described MU-MIMO processing method of claim 1, it is characterized in that this method further comprises based on orthogonal set: when number of transmit antennas more than or equal to 8 the time, the matrix of described specific orthogonal set precoding is:

$\left[\begin{array}{cccc}{S}_{11}& S_{12}& S_{23}& S_{24}\\ -S_{12}^{*}& S_{11}^{*}& -S_{24}^{*}& S_{23}^{*}\\ S_{21}& S_{22}& S_{13}& S_{14}\\ -S_{22}^{*}& S_{21}^{*}& -S_{14}^{*}& S_{13}^{*}\end{array}\right]$

Wherein, S _1iThe data that expression user 1 sends, S _2iThe data that expression user 2 sends, i=1,2,3,4;

Data flow to user 1 is mapped in the matrix of space-frequency coding by layering and diversity precoding, and user 2 data flow then is mapped in the matrix of space-frequency coding by the diversity pre-coding matrix of complementation.

4. according to the described MU-MIMO processing method of claim 1, it is characterized in that this method further comprises based on orthogonal set: when number of transmit antennas more than or equal to 8 the time, the matrix of described specific orthogonal set precoding is:

$\left[\begin{array}{cccc}{S}_{11}& S_{12}& -S_{13}^{*}& -S_{14}^{*}\\ -S_{12}^{*}& S_{11}^{*}& S_{14}& -S_{13}\\ S_{13}& S_{14}& S_{11}^{*}& S_{12}^{*}\\ -S_{14}^{*}& S_{13}^{*}& -S_{12}& S_{11}\end{array}\right],\left[\begin{array}{cccc}{S}_{21}& S_{22}& -S_{23}^{*}& -S_{24}^{*}\\ -S_{22}^{*}& S_{21}^{*}& S_{24}& -S_{23}\\ S_{23}& S_{24}& S_{21}^{*}& S_{22}^{*}\\ -S_{24}^{*}& S_{23}^{*}& -S_{22}& S_{21}\end{array}\right]$

Wherein, S _1iThe data that expression user 1 sends, S _2iThe data that expression user 2 sends, i=1,2,3,4;

Data flow to user 1 is mapped in the matrix of space-frequency coding by layering and diversity precoding, and user 2 data flow then is mapped in the matrix of space-frequency coding by the diversity pre-coding matrix identical with user 1.

5. according to each described MU-MIMO processing method in the claim 1 to 4, it is characterized in that described multi-user pre-coding or BF handle, and are specially based on orthogonal set:

The data of the different user in the matrix of described space-frequency coding be multiply by different precoding vectors respectively, or multiply by different B F vector.

6. MU-MIMO processing unit based on orthogonal set is characterized in that this device comprises:

The orthogonal set precoding module is used for data flow to different user by layering and specific orthogonal set precoding, is mapped in the matrix of space-frequency coding;

The multi-user pre-coding module is used for that the data of the different user of the matrix of described space-frequency coding are carried out multi-user pre-coding or BF respectively and handles;

Transmitter module is used for the outwards emission after the resource mapping of the data after the described multi-user pre-coding resume module.

7. according to the described MU-MIMO processing unit of claim 6 based on orthogonal set, it is characterized in that, when number of transmit antennas more than or equal to 8 the time, described orthogonal set precoding module is further used for, data flow to user 1 is mapped in the matrix of space-frequency coding by layering and diversity precoding, and user 2 data flow then is mapped in the matrix of space-frequency coding by the diversity pre-coding matrix of complementation.

8. according to the described MU-MIMO processing unit of claim 6 based on orthogonal set, it is characterized in that, when number of transmit antennas more than or equal to 8 the time, described orthogonal set precoding module is further used for, data flow to user 1 is mapped in the matrix of space-frequency coding by layering and diversity precoding, and user 2 data flow then is mapped in the matrix of space-frequency coding by the diversity pre-coding matrix identical with user 1.

9. according to claim 6 or 7 or 8 described MU-MIMO processing unit based on orthogonal set, it is characterized in that, described multi-user pre-coding module is further used for, the data of the different user in the matrix of described space-frequency coding be multiply by different precoding vectors respectively, or multiply by different B F vector.

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