CN109861729B - Single-user multi-antenna signal transceiver system and signal processing method in MIMO system - Google Patents

Abstract

The invention discloses a single-user multi-antenna signal transceiver in a MIMO system and a signal processing method thereof. The transceiver includes a base station and a multi-antenna user, the base station has Nr antennas, the user has Nt antennas, and the user end and The base station is equipped with K radio frequency links, and the required number of radio frequency links K is much smaller than the number of antennas, and a specific connection method and information processing method are adopted, so that the signal transmission and reception and processing performance is compared with the assumption that the channel state information is completely known. The traditional transceiver system has only a slight loss; the construction cost and power loss are reduced, and the occupation area required for the construction of the receiver is saved.

Description

Single-user multi-antenna signal transceiver system and signal processing method in MIMO system

technical field

The invention belongs to the technical field of wireless communication, and in particular relates to a single-user multi-antenna signal receiving and transmitting system and a signal processing method thereof in a MIMO system.

Background technique

In recent years, with the rapid increase in the number of wireless communication system users and the pursuit of high voice quality and high data transmission rate, people's demand for bandwidth has increased dramatically, and spectrum resources are not unlimited. Therefore, it is not practical to increase the transmission rate by simply increasing the bandwidth. Therefore, to transmit data at a higher rate, a new technology with high spectrum utilization must be supported. Multiple-Input Multiple-Output (Multiple-Input Multiple-Output) is one of the major technological breakthroughs in the field of digital communication in recent years, and it plays a significant role in improving the spectrum utilization and channel capacity of wireless communication systems. The MIMO system realizes the parallel transmission of multiple signal streams. Compared with the traditional single-input single-output (SISO) system, the receiving end of the system realizes that the received signal of each receiving antenna is the superposition of multiple transmitting antenna signals. However, there are problems such as selective fading of the channel, inter-symbol interference, and path loss in the transmission process.

Due to the existence of multiple antennas, the design of space-time combiners and signal detection to eliminate spatial interference becomes extremely complicated. Compared with the single-antenna system, the transceiver system of MIMO system has significantly increased complexity. For example, MIMO channel estimation will lead to an increase in complexity, because each path delay of the entire channel matrix needs to be tracked and updated by technology, instead of only tracking and updating. Update a single coefficient; the existing large-scale antenna transceiver system requires a lot of RF radio frequency links to process signals due to the large number of base stations and user-end antennas, but the cost of building RF radio frequency links is high and the power loss is large , and there are requirements for land occupation and construction area. Therefore, it is necessary to research and design a large-scale antenna transceiver system with low cost and low complexity.

SUMMARY OF THE INVENTION

Based on the above deficiencies in the prior art, the present invention provides a single-user multi-antenna signal transceiving and a signal processing method thereof in a MIMO system.

In order to achieve the above-mentioned purpose of the invention, the present invention adopts the following technical solutions:

The present invention provides a single-user multi-antenna signal transceiving system in a MIMO system, including a base station and a multi-antenna user, the base station has Nr antennas to receive signals sent by the user's Nt antennas, and both Nt and Nr are greater than 1 positive integer;

The user end includes a user transmitter and a user receiver, the base station includes a base station transmitter and a base station receiver, and the user transmitter and the base station receiver form an uplink.

In the uplink, the user transmitter includes:

K phase-shift control units, the phase-shift control units include Nt sub-control units connected in parallel with each other, each sub-control unit includes an adjustment switch and a phase-measuring phase shifter, and the phase-measuring phase shifter is connected to the adjustment switch;

The K radio frequency links transmit the transmitted signals of the user terminal, and are respectively connected with the Nt phase-measuring phase-shifters in each phase-shifting control unit in a one-to-one correspondence;

Nt adders are respectively connected with the phase measuring phase shifters in each phase shifting control unit in one-to-one correspondence;

The base station receiving end includes:

Nr LNAs are connected to Nr antennas in one-to-one correspondence;

Nr phase-shift control units are connected to Nr low-noise power amplifiers in one-to-one correspondence; the phase-shift control units include K sub-control units connected in parallel with each other, each sub-control unit includes an adjustment switch and a phase measuring phase shifter, The phase measuring phase shifter is connected with the adjustment switch, and the adjustment switch is connected with the corresponding low-noise power amplifier;

The K adders are respectively connected with the phase-detecting phase-shifters in each phase-shifting control unit in a one-to-one correspondence;

K radio frequency links are connected with K adders in one-to-one correspondence;

K analog-to-digital converters are connected with the K radio frequency links in one-to-one correspondence;

A decoder, connected with K analog-to-digital converters.

As a preferred solution of the present invention, the user receiving end and the base station transmitting end form a downlink, and in the downlink, the base station transmitting end includes:

Nr phase-shift control units, the phase-shift control units include an adder and K sub-control units in parallel with each other, each sub-control unit includes an adjustment switch and a phase-measuring phase shifter, and the adjustment switch and the phase-measuring phase shifter connection, the phase measuring phase shifter is connected with the adder;

K radio frequency links, which transmit signals sent by the base station, and are respectively connected with each phase-shift control unit in a one-to-one correspondence;

The user receiving end includes:

Nt phase-shift control units are connected with Nt antennas in one-to-one correspondence; the phase-shift control unit includes Nt sub-control units connected in parallel with each other, each sub-control unit includes an adjustment switch and a phase-measuring phase shifter, which measures the phase shift The phase device is connected with the adjustment switch;

The K adders are respectively connected with the K phase-measuring phase-shifters in each phase-shifting control unit in a one-to-one correspondence;

The K radio frequency chains are connected to the K adders in one-to-one correspondence.

Based on the above-mentioned transceiver system, the present invention also provides a single-user multi-antenna signal processing method in a MIMO system, comprising the following steps:

In the uplink,

S1. The user transmitter sends a training sequence to estimate the channel;

S2. The transmitting end of the user sends a data signal, the receiving end of the base station receives the signal, and processes the signal through a low-noise power amplifier, a phase measuring phase shifter, an adder, a radio frequency link, and an analog-to-digital converter;

S3. Decode the processed signal input to the decoder to obtain the data signal sent by the user node;

In downlink,

S4, perform parameter setting on the phase-shift control units of the base station transmitter and the user receiver in the downlink by the uplink training result;

S5. The base station transmitter sends a data signal, the user receiver receives the signal, and processes the signal through a low-noise power amplifier, a phase measuring phase shifter, an adder, a radio frequency link, and an analog-to-digital converter;

S6. Decode the processed signal.

As a preferred solution of the present invention, step S1 specifically includes:

S11. Set the t-th direction-finding phase shifter of the k-th phase-shift control unit of the user transmitting end to q _k,t , where q _k,t is the element of the k-th column and the t-th row in the matrix Q, and the matrix Q is the first K columns of the N _t -dimensional DFT matrix;

S12. The kth radio frequency link of the user transmitter sends a training symbol, and the training symbols are all 1, turn on all switches in the kth phase-shift control unit of the user transmitter, and disconnect the switches of other phase-shift control units. The processed transmit signal x _k can be expressed as:

x _k =q _k s

为矩阵Q中的第k列向量，s为训练符号1；Among them, k=1,2,...,K,

is the k-th column vector in the matrix Q, and s is the training symbol 1;

Turn on the kth switch of each phase-shift control unit at the base station receiving end, and disconnect the other switches of each phase-shift control unit at the base station receiving end, the signal y _k received by the base station is expressed as:

Among them, k=1,2,...,K, ρ is the signal-to-noise ratio, H is the N _r ×N _t -dimensional channel matrix, w _k is the N _r ×1-dimensional complex additive white Gaussian noise, and its terms independent and submissive

Denote the signal received by the k-th channel of the phase-shift control unit of the r-th receiving antenna of the base station as h _r,k , and denote its phase as φ _r,k (r=1,2,...,N _t ), that is, The transmission matrix after the transmission signal is transmitted through the transmission preprocessing unit and the wireless communication channel is:

The phase φ _r,k of h _r,k is taken as a negative number and stored in the corresponding phase measuring phase shifter, and the phase matrix is recorded as:

As a preferred solution of the present invention, step S1 also includes:

S13, turn on all switches of the phase shift control unit of the kth radio frequency link of the user transmitter, and the kth radio frequency link sends training symbol 1;

送入第k个加法器，再经过第k个RF射频链路及第k个模数转换器处理，得到接收信号z_0k：Turn on the kth switch of the phase shift control unit of all receiving antennas of the base station, and turn off other switches of the phase shift control unit of all receiving antennas of the base station. When the signal received by the base station passes through the phase shifter, it is multiplied by

It is sent to the kth adder, and then processed by the kth RF radio frequency chain and the kth analog-to-digital converter to obtain the received signal z _0k :

k＝1,2,…,K，w_r,k表示基站的第r根天线收到的噪声；in,

k=1,2,...,K, w _r,k represents the noise received by the rth antenna of the base station;

S14. The k1 and k2 radio frequency links of the user transmitter simultaneously send training symbols, and the training symbol is 1, where k1, k2=1, 2...K, and k1≠k2, and the k1 and k2 of the user transmitter are connected at the same time. The adjustment switches in the phase-shift control unit, and the rest of the radio frequency links do not send signals, the signal matrix y _{k1, k2} received by the base station antenna is:

的第k1、k2列，w_k1,k2为Nr×1维的复加性高斯白噪声，其各项独立且服从

Among them, h _k1 and h _k2 are transmission matrices

The k1 and k2 columns of , w _{k1 and k2} are complex additive white Gaussian noise of Nr×1 dimension, and its terms are independent and obey the

与

后送入相应加法器，再经过相应的射频链路和模数转换器处理，得到两个信号z_k1,k2和z_k2,k1，表示为：S15. Turn on the control switches of the k1th and k2th phase measuring phase shifters of all phase shift control units at the base station receiving end, and the signals y _{k1 and k2} received by the base station antenna pass through the k1th phase shifter of each phase shift control unit. and the k2th phase-detecting phase shifter, and multiply by

and

After that, it is sent to the corresponding adder, and then processed by the corresponding radio frequency link and analog-to-digital converter to obtain two signals z _k1,k2 and z _k2,k1 , which are expressed as:

通过训练得到g_k1,k2、g_k2,k1，即得到

的估计矩阵G为：S16, order

Obtain g _k1,k2 , g _k2,k1 through training, namely get

The estimated matrix G is:

As a preferred solution of the present invention, step S2 specifically includes:

S21. The user transmitter sends a data signal, and the data symbol sent by the k-th radio frequency link is denoted as _sk , turn on all adjustment switches, and let the signal received by the r-th antenna be y _r , there are:

Among them, n _r is Gaussian white noise, and obeys

再经过对应的加法器、射频链路、模数转换器处理，得到的信号分别记为[r₁，r₂，…，r_K]，表示为：S22. The signal received by the antenna passes through the corresponding phase measuring phase shifter and is multiplied by

After processing by the corresponding adder, radio frequency link, and analog-to-digital converter, the obtained signals are respectively recorded as [r ₁ , r ₂ , ..., r _K ], which are expressed as:

为处理后的噪声，独立且服从

in,

is the processed noise, independent and subject to

As a preferred solution of the present invention, the decoding method in step S3 is:

则用户发射端第k条射频链路所发送的数据符号记为s_k的解码为Let G _ZF = (G ^H G) ^-1 G ^H ,

Then the data symbol sent by the kth RF link of the user transmitter is denoted as _sk and the decoding is

Among them, (Y _ZF ) _k is the k-th component in Y _ZF , and ε is the constellation used by the user to send the signal.

As a preferred solution of the present invention, step S4 specifically includes:

S41, obtain the setting value E ^H of the base station phase-measuring phase shifter in the downlink by the uplink training; the phase of the kth phase-measuring phase shifter of the phase-shifting control unit corresponding to the rth antenna of the base station transmitting end Set to φ _r,k , and denote the phase matrix as:

(

表示q_t,k的共轭)，其中q_t,k是矩阵Q中的第t列第k行的元素。S42. Set the k-th direction finding phase shifter of the t-th phase-shifting control unit at the user receiving end to

(

represents the conjugate of q t, _k ), where q _t,k is the element in the t-th column and the k-th row of the matrix Q.

As a preferred solution of the present invention, step S5 specifically includes:

S51. Turn on all the adjustment switches, the base station transmitter sends a data signal, the data symbol sent by the kth radio frequency link is marked as _sk ', and the transmission of the transmitted signal after passing through each phase-shift control unit of the base station and the wireless communication channel is marked. The matrix is

S52. Denote the signal received by the rth antenna of the user receiving end as y _r ', then there are:

Among them, n _r is Gaussian white noise, and obeys

The transmission equation from the transmitter of the base station to the receiver antenna of the receiver of the user can be expressed as

Among them, W represents the N _r ×1-dimensional Gaussian white noise vector, which is independent and obeys the

再经过对应的加法器、射频链路、模数转换器处理，得到总体传输方程：S53. The signal received by the antenna of the user's receiving end passes through the corresponding phase measuring phase shifter and is multiplied by

After processing by the corresponding adder, radio frequency link, and analog-to-digital converter, the overall transmission equation is obtained:

独立且服从

in,

independent and submissive

As a preferred solution of the present invention, step S6 is specifically:

Perform ZF decoding on the processed signal,

Let G' _ZF = ((Q ^H H ^H E) ^H Q ^H H ^H E) ^-1 (Q ^H H ^H E) ^H , Y' _ZF = G' _ZF Y, then the data symbol _sk ' sent by the base station is decoded to

Among them, (Y' _ZF ) _k is the k-th component in Y' _ZF , and ε is the constellation used by the user to send the signal.

Compared with the prior art, the present invention has the following beneficial effects:

In the prior art, the transmitting end of the user needs N _t radio frequency links, and the receiving end of the base station needs N _r radio frequency links, but using the transceiver system and the information processing method of the present invention, in the uplink and downlink, Both the user end and the base station only need K RF links to process the received signal, and the performance is only slightly lost compared with the traditional transceiver system; the construction cost and power loss are reduced, and the occupation required for the construction of the transceiver system is saved. area.

At the same time, most of the existing researches are based on the perfect assumption that both receivers know the channel information completely, but this is difficult to achieve in reality. The transceiver system proposed by the present invention can record the channel information required for channel estimation and decoding by using a phase measuring phase shifter by sending training symbols, which is established on a realistic basis.

Description of drawings

FIG. 1 is a schematic diagram of the uplink connection structure in the single-user multi-antenna signal transceiving system according to the present invention.

FIG. 2 is a simulation diagram of channel capacity of a transceiver system in an uplink when K=2 in an embodiment of the present invention.

FIG. 3 is a simulation diagram of channel capacity of a transceiver system in an uplink when K=8 in an embodiment of the present invention.

FIG. 4 is a schematic diagram of a downlink connection structure in the single-user multi-antenna signal transceiving system according to the present invention.

FIG. 5 is a simulation diagram of the channel capacity of the transmission and reception system in the downlink when K=8 in the embodiment of the present invention.

Detailed ways

In order to describe the embodiments of the present invention more clearly, the following will describe specific embodiments of the present invention with reference to the accompanying drawings. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative efforts, and obtain other implementations.

Applying the single-user multi-antenna signal transceiver system of the present invention to a specific case,

As shown in Figure 1, in the single-user multi-antenna signal transceiver system, the connection structure of the user end and the base station end in the uplink, it is assumed that the number of antennas at the user end is N _t =16, the number of antennas at the base station end is N _r =64, the radio frequency chain The number of roads K = 2,

The information processing method in the uplink includes the following steps:

S1: User sends training sequence

The receiving end estimates the signal, and the specific operation is divided into the following steps:

S1. The multi-antenna user sends a training sequence to estimate the channel;

Wherein step S1 specifically includes:

S11: Set the t-th direction-finding phase shifter of the k-th phase-shift control unit of the user end to q _k,t , where q _k,t is an element of the k-th column and the t-th row in the DFT matrix Q.

S12: The first radio frequency link of the user end sends training symbols, and the training symbols are all standardized as 1, turn on all switches C ₁₁ , C ₁₂ in the first phase-shifting control unit of the transmitting end, and turn off the switches of other phase-shifting control units. switch, the preprocessed transmit signal x ₁ can be expressed as:

x ₁ =q ₁ s

为2维DFT矩阵Q中的第1列向量，s为训练符号1。接通基站各接收天线移相控制单元的第1个开关，断开其他开关，则基站收到的信号y₁表示为：in,

is the first column vector in the 2D DFT matrix Q, and s is the training symbol 1. Turn on the first switch of each receiving antenna phase shift control unit of the base station, and turn off the other switches, the signal y ₁ received by the base station is expressed as:

Among them, k=1,2, ρ is the signal-to-noise ratio, H is the N _r ×N _t -dimensional channel matrix, w _k is the N _r ×1-dimensional complex additive white Gaussian noise, and its terms are independent and obey the

Denote the signal received by the kth channel of the phase shift control unit of the first receiving antenna of the base station as h _1,k , and denote its phase as φ _1,k .

The second radio frequency link of the user end sends training symbols, and the training symbols are all standardized as 1, turn on all switches C ₂₁ , C ₂₂ in the second phase-shift control unit of the transmitting end, and turn off the switches of other phase-shift control units, The preprocessed transmit signal x ₂ can be expressed as:

x ₂ =q ₂ s

为2维DFT矩阵Q中的第2列向量，s为训练符号1。接通基站各接收天线移相控制单元的第2个开关，断开其他开关，则基站收到的信号y₂表示为：in,

is the second column vector in the 2D DFT matrix Q, and s is the training symbol 1. Turn on the second switch of each receiving antenna phase shift control unit of the base station, and turn off the other switches, the signal y ₂ received by the base station is expressed as:

Among them, k=1,2, ρ is the signal-to-noise ratio, H is the N _r ×N _t -dimensional channel matrix, w _rk is the N _r ×1-dimensional complex additive white Gaussian noise, and its terms are independent and obey the

Denote the signal received by the kth channel of the phase-shift control unit of the second receiving antenna of the base station as h _2,k , and denote its phase as φ _2,k , that is, the transmitted signal is transmitted through the transmission preprocessing unit and the wireless communication channel. The transfer matrix is

The phase φ _r,k (r=1,2,...,N _t ,k=1,2) of h _r,k is taken as a negative number and stored in the corresponding phase shifter to obtain the phase matrix:

送入第1个加法器，再经过第1个RF射频链路及第1个模数转换器处理，得到接收信号z₀₁：S13: Turn on all switches of the phase shift control unit of the first radio frequency link of the user terminal, and the first radio frequency link sends training symbol 1. Turn on the first switch of the phase shift control unit of all the receiving antennas of the base station, and turn off the other switches, then the signal received by the base station is multiplied by the phase shifter.

It is sent to the first adder, and then processed by the first RF radio frequency link and the first analog-to-digital converter to obtain the received signal z ₀₁ :

Wherein, ||h ₁ || ₁ =|h _1,1 |+|h _2,1 |, w _r,1 represents the noise received by the rth antenna of the base station.

送入第2个加法器，再经过第2个RF射频链路及第2个模数转换器处理，得到接收信号z₀₂：S14: Turn on all switches of the phase-shift control unit of the second radio frequency link of the user terminal, and the second radio frequency link sends training symbol 1. Turn on the second switch of the phase shift control unit of all the receiving antennas of the base station, and turn off the other switches, then the signal received by the base station is multiplied by the phase shifter.

It is sent to the second adder, and then processed by the second RF radio frequency link and the second analog-to-digital converter to obtain the received signal z ₀₂ :

Wherein, ||h ₂ || ₁ =|h _1,2 |+|h _2,2 |, w _r,2 represents the noise received by the rth antenna of the base station.

S15: The two radio frequency links of the user end send training symbols at the same time, the training symbol specification is 1, and the adjustment switch in the second phase-shift control unit is turned on at the same time, then the signal matrix y _{1, 2} received by the base station antenna is:

的第1、2列，w_1,2为Nr×1维的复加性高斯白噪声，其各项独立且服从

Among them, h ₁ , h ₂ are transmission matrices

The 1st and 2nd columns of , w _1,2 is the complex additive white Gaussian noise of Nr×1 dimension, and its terms are independent and obey

与

后送入相应加法器，再经过相应的射频链路和模数转换器处理，得到两个信号z_1,2和z_2,1，表示为：The signals y _{1, 2} received by the antenna of the base station pass through each phase-measurement phase shifter of each phase-shift control unit, and are multiplied by

and

Then, it is sent to the corresponding adder, and then processed by the corresponding radio frequency link and analog-to-digital converter to obtain two signals z _1,2 and z _2,1 , which are expressed as:

For convenience, remember

S16: Estimate channel information using MMSE method

Using the channel estimation method of MMSE, after the above steps, denote the signal received by the base station as Z=[z ₀₁ , z ₀₂ , z ₁₁ , z ₁₂ ], so that:

||h ₁ || ₁ can be estimated as:

||h ₂ || ₁ can be estimated as:

g _1,2 can be estimated as:

g _2,1 can be estimated as:

的估计矩阵G为：get

The estimated matrix G is:

S2: Data transmission and decoding

S21: The multi-antenna user terminal sends a data signal, the data symbol sent by the first radio frequency link is denoted as s ₁ , and the data symbol sent by the second radio frequency link is denoted as s ₂ , all adjustment switches are turned on, and the first The signal received by r antennas is y _r , then there are:

It can be expressed as:

其中ρ为信噪比，W其中为N_r×1维的高斯白噪声，且服从

which is

where ρ is the signal-to-noise ratio, W where is N _r ×1-dimensional Gaussian white noise, and obeys

再经过对应的加法器、射频链路、模数转换器处理，得到的信号分别记为[r₁，r₂，…，r_K]，表示为：S22, the signal passes through the corresponding phase measuring phase shifter and is multiplied by

After processing by the corresponding adder, radio frequency link, and analog-to-digital converter, the obtained signals are respectively recorded as [r ₁ , r ₂ , ..., r _K ], which are expressed as:

为处理后的噪声，独立且服从

in,

is the processed noise, independent and subject to

S3: Decoding with ZF

The specific decoding method is as follows, let G _ZF =(GH G) ^{-1 G H ,}

Then the symbols sent by the two links can be solved as:

Among them, (Y _ZF ) _k is the k-th component in Y _ZF , and ε is the constellation used by the user to send the signal.

As shown in Figure 2 and Figure 3, the object of comparison in the simulation diagram is the ideal situation that both the base station and the user are fully aware of the channel information, and the rank of precoding is K, but in reality this ideal situation is very difficult to achieve. It can be seen from the simulation in FIG. 3 that the transceiver system structure according to the present invention only uses the channel capacity of K radio frequency links, which is about 3dB lost compared to the ideal situation in which the channel information is completely known.

As shown in Figure 4, in the single-user multi-antenna signal transceiving system, the connection structure between the user terminal and the base station in the downlink, it is assumed that the number of antennas at the user terminal is N _t =16, the number of antennas at the base station is N _r =64, and the radio frequency chain The number of paths K=8. The corresponding signal processing method in the downlink includes the following steps:

S4. Perform parameter setting on the phase shift control units of the base station transmitter and the user receiver in the downlink based on the uplink training result.

S5. The base station sends the data signal, the antenna of the multi-antenna user receives the signal, and processes the signal through a low-noise power amplifier, a phase measuring phase shifter, an adder, a radio frequency link, and an analog-to-digital converter;

S6. Decode the processed signal.

Specifically, step S4 includes the following steps:

S41. Obtain the setting value E ^H of the base station phase measuring phase shifter in the downlink system from the uplink training. Set the phase of the k-th phase-measurement phase shifter of the phase-shift control unit corresponding to the r-th antenna at the base station as φ _r,k , and denote the phase matrix as:

(

表示q_t,k的共轭)，其中q_t,k是矩阵Q中的第t列第k行的元素。S42. Set the k-th direction finding phase shifter of the t-th phase-shifting control unit of the user terminal to

(

represents the conjugate of q t, _k ), where q _t,k is the element in the t-th column and the k-th row of the matrix Q.

Specifically, step S5 includes the following steps:

S51, all adjustment switches are closed, the base station sends a data signal, and the data symbol sent by the kth radio frequency link is denoted as _sk '. The transmission matrix after the transmitted signal is transmitted through each phase-shift control unit of the base station and the wireless communication channel is recorded as

S52. Denote the signal received by the rth antenna of the user terminal as y _r ', then there are:

Among them, n _r is Gaussian white noise, and obeys

The transmission equation from the base station to the receiving antenna of the user can be expressed as

Among them, W represents the N _r ×1-dimensional Gaussian white noise vector, independent and obeying the

再经过对应的加法器、射频链路、模数转换器处理，得到最后的总体传输方程：S53. The signal received by the antenna at the user end passes through the corresponding phase measuring phase shifters and is multiplied by

After processing by the corresponding adder, radio frequency link, and analog-to-digital converter, the final overall transmission equation is obtained:

独立且服从

in,

independent and submissive

S6. Perform ZF decoding on the processed signal

Let G' _ZF =((Q ^H H ^H E) ^H Q ^H H ^H E) ^-1 (Q ^H H ^H E) ^H , Y' _ZF =G' _ZF Y, then the data symbol _sk ' sent by the base station has decoded to

Among them, (Y' _ZF ) _k is the k-th component in Y' _ZF , and ε is the constellation used by the user to send the signal.

As shown in FIG. 5 , in the downlink, the transceiver system according to the present invention only uses K radio frequency links, which loses about 3dB compared to the ideal situation where the channel information is completely known.

Compared with the prior art that the base station needs Nr radio frequency chains to process and the user terminal needs Nt radio frequency chains, the transceiver system and the signal processing method thereof of the present invention only need K RF chains to process received signals, and There is no need to use the perfect assumption that the receiver and both parties fully know the channel information, which reduces the construction cost and power loss, and saves the occupied area required for the construction of the transceiver system.

The above is only a detailed description of the preferred embodiments and principles of the present invention. For those of ordinary skill in the art, according to the ideas provided by the present invention, there will be changes in the specific implementation, and these changes should also be It is regarded as the protection scope of the present invention.

Claims (9)

1. A single-user multi-antenna signal transceiving system in a MIMO system, comprising a base station and a multi-antenna user, characterized in that:

   the base station has N_rThe root antenna being arranged to receive signals transmitted by Nt antennas of a user, N_t、N_rAre all positive integers greater than 1;

   the user terminal comprises a user transmitting terminal and a user receiving terminal, the base station terminal comprises a base station transmitting terminal and a base station receiving terminal,

   the user transmitting end and the base station receiving end form an uplink, in which,

   the user transmitting terminal includes:

   k phase shift control units including N_tEach sub-control unit comprises an adjusting switch and a phase measuring phase shifter, and the phase measuring phase shifter is connected with the adjusting switch;

   k radio frequency links for transmitting the sending signals of the user end and the N in each phase shift control unit respectively_tThe phase measuring phase shifters are connected in a one-to-one correspondence manner;

   N_tthe adders are respectively and correspondingly connected with 1 phase measuring phase shifter in the K phase shift control units;

   the base station receiving end comprises:

   N_ra low noise power amplifier, and N_rThe root antennas are connected in a one-to-one correspondence manner;

   N_rphase shiftControl unit, with N_rThe low-noise power amplifiers are connected in a one-to-one correspondence manner; the phase-shifting control unit comprises K sub-control units which are connected in parallel, each sub-control unit comprises an adjusting switch and a phase-measuring phase shifter, the phase-measuring phase shifters are connected with the adjusting switches, and the adjusting switches are connected with corresponding low-noise power amplifiers;

   k adders respectively connected to N_r1 phase measuring phase shifters in the phase shift control units are correspondingly connected;

   k radio frequency links which are connected with the K adders in a one-to-one correspondence manner;

   k analog-to-digital converters are connected with the K radio frequency links in a one-to-one correspondence manner;

   the decoder is connected with the K analog-to-digital converters;

   the base station transmitting end and the user receiving end form a downlink, in which,

   the base station transmitting end comprises:

   N_rthe phase-shifting control unit comprises K sub-control units which are connected in parallel, each sub-control unit comprises an adjusting switch and a phase-measuring phase shifter, and the adjusting switches are connected with the phase-measuring phase shifters;

   N_rthe adders are respectively connected with the phase measuring phase shifters in the phase shift control units in a one-to-one correspondence manner;

   k radio frequency links are used for transmitting the sending signals of the base station end and are connected with each phase-shifting control unit;

   the user receiving end includes:

   N_ta phase shift control unit, and N_tThe root antennas are connected in a one-to-one correspondence manner; the phase-shifting control unit comprises K sub-control units which are connected in parallel, each sub-control unit comprises an adjusting switch and a phase-measuring phase shifter, and the phase-measuring phase shifters are connected with the adjusting switches;

   k adders respectively connected to N_t1 phase measuring phase shifters in the phase shift control units are correspondingly connected;

   and the K radio frequency links are correspondingly connected with the K summers one by one.
2. 2. A method for processing a single-user multi-antenna signal in a MIMO system, which employs the single-user multi-antenna signal transceiving system in the MIMO system of claim 1, wherein: the method comprises the following steps:

   in the uplink, the base station sets a transmission power,

   s1, the user transmitting terminal sends a training sequence to estimate the channel;

   s2, a user transmitting end sends a data signal, a base station receiving end receives the signal, and the signal is processed through a low noise power amplifier, a phase measurement phase shifter, an adder, a radio frequency link and an analog-to-digital converter;

   s3, inputting the processed signals into a decoder for decoding to obtain data signals sent by the user nodes;

   in the downlink, the number of channels in the downlink,

   s4, setting parameters of phase shift control units of a base station transmitting end and a user receiving end in a downlink according to the uplink training result;

   s5, a base station transmitting end sends data signals, a user receiving end receives the signals, and the signals are processed through a low noise power amplifier, a phase measurement phase shifter, an adder, a radio frequency link and an analog-to-digital converter;

   and S6, decoding the processed signal.
3. 3. The method of claim 2, wherein: step S1 specifically includes:

   s11, setting the t direction-finding phase shifter of the k phase shift control unit at the user transmitting end as q_k,tWherein q is_k,tIs an element of the kth column, the tth row in the matrix Q, which is N_tThe first K columns of the dimension DFT matrix;

   s12, the kth radio frequency link of the user transmitting end sends training symbols, the training symbols are all 1, all switches in the kth phase-shift control unit of the user transmitting end are switched on, switches of other phase-shift control units are switched off, and the sending signal x after pretreatment is sent_kExpressed as:

   x_k＝q_ks

   wherein K is 1,2, …, K,

   

   is the k column vector in the matrix Q, s is the training symbol 1;

   switching on the kth switch of each phase shift control unit at the receiving end of the base station, switching off other switches of each phase shift control unit at the receiving end of the base station, and receiving a signal y by the base station_kExpressed as:

   

   where K is 1,2,., K, ρ is the signal-to-noise ratio, and H is N_r×N_tDimensional channel matrix, w_kIs N_rComplex additive white Gaussian noise of x 1 dimension, each independent and obedient

   

   The signal received by the kth path of the phase shift control unit of the r receiving antenna of the base station is recorded as h_r,kRecording the phase as phi_r,k，r＝1,2,...,N_tI.e. the transmission matrix of the transmitted signal after transmission through the transmit preprocessing unit and the wireless communication channel is

   

   H is to be_r,kPhase phi of_r,kTaking a negative number, storing the negative number in a corresponding phase measurement phase shifter, and recording a phase matrix as follows:

   
4. 4. the method of claim 3, wherein: step S1 further includes:

   s13, switching on all switches of a phase shift control unit of a kth radio frequency link at a user transmitting end, wherein the kth radio frequency link sends a training symbol 1;

   switching on the kth switch of all receiving antenna phase shift control units of the base station, switching off other switches of all receiving antenna phase shift control units of the base station, multiplying the signal received by the base station when passing through the phase shifter

   

   Sending the signal to a k adder, and processing the signal by a k RF link and a k analog-to-digital converter to obtain a received signal z_0k：

   

   Where p represents the signal-to-noise ratio,

   

   w_r,krepresenting the noise received by the r-th antenna of the base station;

   s14, the K1 and K2 radio frequency links of the user transmitting end simultaneously transmit training symbols, the training symbols are 1, wherein K1, K2 is 1,2 … K, and K1 is not equal to K2, adjusting switches in the K1 and K2 phase shift control units of the user transmitting end are switched on simultaneously, the rest radio frequency links do not transmit signals, and then a signal matrix y received by the base station antenna is transmitted_k1,k2Comprises the following steps:

   

   wherein h is_k1、h_k2For transmission matrix

   

   K1, k2 column, w_k1,k2Is Nr × 1-dimensional complex additive white Gaussian noise, each independent and obedient

   

   S15, switching on the control switches of the phase-measuring phase shifters of the k1 th and the k2 th of all the phase-shifting control units at the receiving end of the base station, so that the signal y received by the antenna of the base station_k1,k2Passing through the phase-shift control units to obtain the k1 th and k2 th phase-measuring phase shifters, and multiplying the phase-measuring phase shifters by the phase-measuring

   

   And

   

   then sent to corresponding adder, and processed by corresponding radio frequency link and analog-to-digital converter to obtain two signals z_k1,k2And z_k2,k1Expressed as:

   

   

   s16, order

   

   G is obtained by training_k1,k2、g_k2,k1To obtain

   

   The estimation matrix G of (a) is:

   
5. 5. the method of claim 2, wherein: step S2 specifically includes:

   s21, user transmitting end sends data signal, data symbol sent by k-th radio frequency link is marked as S_kIs connected throughAll the regulating switches make the signal received by the r-th antenna be y_rThen, there are:

   

   wherein n is_rIs white Gaussian noise and is obeyed

   

   ρ represents the signal-to-noise ratio;

   s22, the signals received by the antennas pass through the corresponding phase measuring phase shifters and are multiplied by the phase measuring phase shifters

   

   The signals are processed by corresponding summers, radio frequency links and analog-to-digital converters to obtain signals which are respectively marked as r₁，r₂，…，r_K]Expressed as:

   

   wherein,

   

   independent and compliant for processed noise

   
6. 6. The method of claim 2, wherein: the decoding method in step S3 is:

   let G_ZF＝(G^HG)^-1G^H，

   

   The data symbol sent by the kth radio frequency link of the user transmitting terminal is marked as s_kIs decoded into

   

   Wherein (Y)_ZF)_kIs Y_ZFThe kth component in (e) is a constellation adopted by a user to send a signal; ρ represents the signal-to-noise ratio.
7. 7. The method of claim 2, wherein: step S4 specifically includes:

   s41, obtaining the setting value E of the base station phase measuring phase shifter in the downlink by the uplink training^H(ii) a Setting the phase of the kth phase measurement phase shifter of the phase shift control unit corresponding to the r antenna at the transmitting end of the base station as phi_r,kThe phase matrix is written as:

   

   s42, setting the kth direction-finding phase shifter of the tth phase shift control unit at the receiving end of the user to be

   

   (

   

   Denotes q_t,kConjugate of (b) wherein q_t,kIs an element of the kth column and kth row in the matrix Q.
8. 8. The method of claim 7, wherein: step S5 specifically includes:

   s51, switching on all the adjusting switches, the transmitting end of the base station sends data signals, the data symbol sent by the kth radio frequency link is marked as S_kThe transmission matrix of the transmitted signal after passing through each phase shift control unit of the base station and the wireless communication channel is

   

   S52, recording the signal received by the r-th antenna at the receiving end of the user as y_r', then there are:

   

   wherein n is_rIs white Gaussian noise and is obeyed

   

   The transmission equation from the transmitting end of the base station to the receiving antenna of the receiving end of the user can be expressed as

   

   Wherein W represents N_rX 1-dimensional Gaussian white noise vector, independent and obedient

   

   ρ represents the signal-to-noise ratio;

   s53, the signals received by the antenna at the receiving end of the user pass through the corresponding phase-measuring phase shifter and are multiplied by

   

   And processing the data by a corresponding adder, a radio frequency link and an analog-to-digital converter to obtain an overall transmission equation:

   

   wherein,

   

   independent and compliant

   
9. 9. The method of claim 8, wherein: step S6 specifically includes:

   the processed signal is ZF decoded,

   line G'_ZF＝((Q^HH^HE)^HQ^HH^HE)^-1(Q^HH^HE)^H，Y′_ZF＝G′_ZFY, then the data symbol s sent by the base station_kDecoding of

   

   Wherein, (Y'_ZF)_kIs Y'_ZFThe kth component in (e) is a constellation adopted by a user to send a signal; ρ represents the signal-to-noise ratio.

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