WO2022067824A1

WO2022067824A1 - Signal transmission method and related apparatus

Info

Publication number: WO2022067824A1
Application number: PCT/CN2020/119757
Authority: WO
Inventors: 高翔; 刘鹍鹏
Original assignee: 华为技术有限公司
Priority date: 2020-09-30
Filing date: 2020-09-30
Publication date: 2022-04-07
Also published as: CN116235415A

Abstract

The present application provides a signal transmission method and related apparatus. The signal transmission method comprises: a terminal device receiving a first received signal; the first received signal is pre-coded by a first reference signal according to a first channel matrix, then sent to the terminal device via a downlink channel corresponding to the terminal device, the first channel matrix being obtained according to a second channel matrix, the number of rows and/or number of columns of the first channel matrix being less than or equal to the sum of the number of receiving antennas of one or more terminal devices participating in multiple-input multiple-output (MIMO) transmission, the second channel matrix being the channel matrix of the downlink channel corresponding to one or a plurality of terminal devices; according to the first received signal, the terminal device obtaining an equivalent channel coefficient corresponding to the terminal device.

Description

Signal transmission method and related device

technical field

The present application relates to the field of communication technologies, and in particular, to a signal transmission method and related devices.

Background technique

The 5G communication system has higher requirements on system capacity and spectral efficiency. In 5G communication systems, massive multiple input multiple output (MIMO) plays a crucial role in the spectral efficiency of the system.

When the MIMO technology is adopted, precoding needs to be performed when the network device sends data to the terminal device through multiple antenna ports. The network device can preprocess the signal to be transmitted by using a precoding matrix matching the channel when the channel state is known, so that the precoded transmission signal is adapted to the channel, thereby improving the transmission performance. In a specific implementation process, the sending device may also perform precoding in other manners. For example, in the case where the channel information cannot be obtained, a preset precoding matrix or a weighting processing method is used to perform precoding and the like.

In the related art, the network device may send a demodulation reference signal (DMRS) to the terminal device, and the DMRS and the data signal perform the same precoding process based on the same precoding matrix. The receiver of the terminal device estimates the equivalent channel matrix or the equivalent channel coefficients by demodulating the reference signal, and estimates the received data signal according to the equivalent channel matrix or the equivalent channel coefficients.

When the THP algorithm in the MIMO scenario performs precoding, the feedback matrix B is used for precoding to eliminate interference. B=GR ^H , R is obtained by performing QR decomposition on the conjugate transposed matrix H ^H of the channel matrix H of all users, and Q is a unitary matrix. The G matrix is a diagonal matrix, and its main diagonal element is the reciprocal of the main diagonal element of the R matrix. The dimension of the user complete channel matrix H is

For large-scale antennas, the number of transmitting antennas is usually large, such as 64T. In addition, when the number of paired users is large,

value is also larger. Therefore, the QR decomposition of the channel matrix H has high complexity. Therefore, in the process of THP precoding, the matrix calculation dimension is large and the complexity is high.

SUMMARY OF THE INVENTION

The present application provides a signal transmission method and a related device, which can reduce the computational difficulty of channel matrix decomposition, reduce the computational complexity of precoding, and improve transmission performance.

In a first aspect, the present application provides a signal transmission method, including: a terminal device receives a first received signal; the first received signal is obtained by precoding a first reference signal according to a first channel matrix, and then sent to the terminal device by the terminal device. If the corresponding downlink channel is sent to the terminal device, the first channel matrix is obtained according to the second channel matrix, and the number of rows and/or columns of the first channel matrix is less than or equal to the one participating in the MIMO transmission. or the sum of the number of receiving antennas of multiple terminal devices, the second channel matrix is the channel matrix of the downlink channel corresponding to the one or more terminal devices; the terminal device obtains the Equivalent channel coefficient corresponding to the terminal device. The equivalent channel coefficients can be used to detect the data signal.

In the technical solution of the present application, the first received signal is sent to the terminal device through the downlink channel corresponding to the terminal device after precoding the first reference signal according to the first channel matrix, and the first channel matrix is based on the first channel matrix. Obtained from the two-channel matrix, the number of rows and/or columns of the first channel matrix is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission, so that the matrix calculation can be reduced in the process of THP precoding. Difficulty, making the calculation of THP precoding simpler.

It should be understood that the precoding in this application may be THP precoding, and may also be other precoding techniques. For example, the precoding may be, but not limited to, symbol level precoding (SLP), vector perturbation (VP) precoding, zero-forcing (ZF) precoding, and the like.

In some possible implementations, the first channel matrix

is obtained by processing the second channel matrix according to the receiving weight matrix W and the weight matrix V.

In this application, the weight matrix may be an outer weight matrix.

In some embodiments, the number of rows of the weight matrix and/or the number of columns of the weight matrix is less than or equal to the sum of the number of receiving antennas of the one or more terminal devices participating in the MIMO transmission.

Optionally, the first channel matrix

second channel matrix

first channel matrix

The number of rows is less than or equal to the sum of the number of receive antennas of n terminal devices participating in MIMO transmission, or the first channel matrix

The number of rows and columns is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission.

Optionally, the first channel matrix

second channel matrix

first channel matrix

The number of columns is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission, or the first channel matrix

For example, the number of rows of the weight matrix V is the sum of the number of transport streams of the one or more terminal devices, and/or the number of columns of the weight matrix is the sum of the number of transport streams of the multiple terminal devices sum of numbers. In this way, by reasonably designing the weight matrix V and the receiving weight matrix W, the first channel matrix can be

The number of rows and columns are the sum L of the total number of transmission streams of one or more terminal devices participating in MIMO transmission, so that the sum L of the total number of transmission streams of n terminal devices participating in MIMO transmission is less than that of multiple terminal devices. The sum of the total number of receiving antennas, and the resulting matrix dimension mismatch problem.

In some embodiments, the first channel matrix

W is the reception weight matrix, V is the weight matrix, and H is the second channel matrix. The number of rows of the reception weight matrix and/or the number of columns of the weight matrix is less than or equal to the number of the participating MIMO transmission. The sum of the number of receive antennas of one or more terminal devices. In this way, the second channel matrix is dimensionally reduced by receiving the weight matrix and the weight matrix to obtain a first matrix whose dimension is less than or equal to the second channel matrix, thereby reducing the computational difficulty of channel matrix decomposition.

Optionally, the receiving weight matrix includes a receiving weight sub-matrix corresponding to the terminal device; the method further includes:

the terminal device receives the second received signal;

Obtaining, by the terminal device, according to the first received signal, the equivalent channel coefficient corresponding to the terminal device includes:

determining, by the terminal device, an estimated receiving weight sub-matrix corresponding to the receiving weight sub-matrix according to the second received signal;

The terminal device obtains an equivalent channel coefficient corresponding to the terminal device according to the estimated reception weight sub-matrix and the first received signal. For example, the terminal device may left-multiply the first received signal by the estimated receiving weight sub-matrix to obtain the third received signal, and then perform channel estimation according to the third received signal and the first reference signal.

In this way, the terminal device determines the estimated receiving weight sub-matrix corresponding to the terminal device according to the receiver type and the second received signal corresponding to the second reference signal. In this application, when performing channel estimation, in addition to the reference signal used for direct channel estimation, the network device also sends another reference signal (second reference signal). This scheme of implicitly indicating the receiving weight sub-matrix through the second reference signal can avoid the signaling notification of the receiving weight matrix, reduce the downlink signaling overhead, and avoid the quantization during notification. performance loss.

Optionally, the weight matrix includes a weight sub-matrix corresponding to the terminal device, and the second received signal is obtained by the network device after precoding the second reference signal according to the weight sub-matrix, The downlink channel corresponding to the terminal device is sent to the terminal device. In this way, the terminal device can estimate the estimated receiving weight sub-matrix corresponding to the terminal device according to the second reference signal.

Optionally, the receiving weight sub-matrix corresponding to the terminal device is obtained according to the channel matrix and the weight matrix corresponding to the terminal device.

In some other possible implementation manners, the first channel matrix

is obtained by processing the second channel matrix according to the receiving weight matrix W.

first channel matrix

second channel matrix

The number of rows of the receiving weight matrix W is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission, that is, the first channel matrix

The number of rows is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission.

Alternatively, the first channel matrix

second channel matrix

The number of columns of the receiving weight matrix W is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission, that is, a channel matrix

The number of columns is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission.

In this way, the second channel matrix is dimensionally reduced by receiving the weight matrix and the weight matrix to obtain a first matrix whose dimension is less than or equal to the second channel matrix, thereby reducing the computational difficulty of channel matrix decomposition.

Optionally, the number of rows of the reception weight matrix is the sum of the numbers of transport streams of the multiple terminal devices. In this way, by reasonably designing the receiving weight matrix W, the first channel matrix can be

The number of rows is the sum L of the total number of transmission streams of one or more terminal devices participating in MIMO transmission, and it can be solved that the sum of the total number of transmission streams L of n terminal devices participating in MIMO transmission is less than the total number of receiving antennas of multiple terminal devices. The sum of the numbers, and the resulting matrix dimension mismatch problem.

Specifically, the receiving weight matrix includes a receiving weight sub-matrix corresponding to the terminal device; the method further includes:

the terminal device receives the second received signal;

The terminal device obtains an equivalent channel coefficient corresponding to the terminal device according to the estimated reception weight sub-matrix and the first received signal.

In this way, the terminal device determines the estimated receiving weight sub-matrix corresponding to the terminal device according to the receiver type and the second received signal corresponding to the second reference signal. In this application, when performing channel estimation, in addition to the reference signal used for direct channel estimation, another reference signal (second reference signal) is also sent. This scheme of implicitly indicating the receiving weight sub-matrix through the second reference signal can avoid the signaling notification of the receiving weight matrix, reduce the downlink signaling overhead, and avoid the quantization during notification. performance loss.

In some implementation manners, the method further includes: receiving, by the terminal device, a first received data signal, where the first received data signal is after the network device precodes the transmitted data signal according to the first channel matrix, It is sent to the terminal device through the downlink channel corresponding to the terminal device; the terminal device detects the first received data signal according to the estimated receiving weight sub-matrix and the equivalent channel coefficient corresponding to the terminal device. In this way, the terminal device can detect the received data signal according to the equivalent channel coefficient.

In some implementation manners, the terminal device detecting the data signal according to the estimated reception weight sub-matrix and the equivalent channel coefficient corresponding to the terminal device comprises: the terminal device uses the estimated reception weight sub-matrix to Multiply the first received data signal to obtain a second received data signal corresponding to the first received data signal; the terminal device obtains the second received data signal and the equivalent channel coefficient corresponding to the terminal device according to the second received data signal an estimation result for the transmitted data signal. In this way, the network device processes the transmitted data signal according to the receiving weight matrix, and the terminal device processes the first received data signal according to the receiving weight matrix. Calculated matches. The reporting or downlink notification of the detection weight matrix can be avoided.

Optionally, the method further includes: sending, by the terminal device, a receiver type of the terminal device, and the receiver type of the terminal device is used by the network device to determine the receiving right matrix. In this way, the network device can determine the reception weight sub-matrix corresponding to the terminal device according to the receiver type reported by the terminal device and according to the preset receiver or reception weight calculation method, so as to obtain the first channel matrix.

In a second aspect, an embodiment of the present application further provides a signal transmission method for multiple-input multiple-output MIMO transmission, including: a network device precoding a first reference signal according to a first channel matrix to obtain a first transmitted signal, the The first channel matrix is obtained according to the second channel matrix. The number of rows and/or columns of the first channel matrix is less than or equal to the sum of the number of receiving antennas of one or more terminal devices participating in the MIMO transmission. The second channel matrix is a channel matrix of downlink channels of the one or more terminal devices; the network device sends the first transmission signal.

It should be understood that the first transmission signal is sent to one or more terminal devices participating in the MIMO transmission. The one or more terminal devices receive respective corresponding first received signals on respective downlink channels.

In the technical solution of the present application, the network device precodes the first reference signal according to the first channel matrix, the first channel matrix is obtained according to the second channel matrix, and the number of rows and/or columns of the first channel matrix is less than or It is equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission, so that the difficulty of matrix calculation can be reduced in the process of THP precoding, and the calculation of THP precoding can be made simpler.

Optionally, the second channel matrix

first channel matrix

Optionally, the second channel matrix

first channel matrix

In some possible implementations, the first channel matrix

W is a receiving weight matrix, V is a weight matrix, and the number of rows of the receiving weight matrix and/or the number of columns of the weight matrix is less than or equal to the sum of the number of receiving antennas of the one or more terminal devices. In this way, the second channel matrix is dimensionally reduced by receiving the weight matrix and the weight matrix to obtain a first matrix whose dimension is less than or equal to the second channel matrix, thereby reducing the computational difficulty of channel matrix decomposition.

Optionally, the number of rows of the receiving weight matrix is the sum of the number of transmission streams of the one or more terminal devices, and/or the number of columns of the weight matrix is the number of transmission streams of the one or more terminal devices. the number of streams. In this way, by reasonably designing the weight matrix V and the receiving weight matrix W, the first channel matrix can be

In some embodiments, the weight matrix includes a weight sub-matrix corresponding to each terminal device in the one or more terminal devices, and the weight sub-matrix corresponding to each terminal device is based on the weight sub-matrix corresponding to the terminal device. The channel matrix of the downlink channel is determined. The weight sub-matrix calculated by the network device only depends on the channel matrix corresponding to each terminal device, and does not depend on the channel information of other users, and does not require joint detection or notification of channel state information of other users.

Optionally, the receiving weight sub-matrix corresponding to each terminal device is obtained according to the channel matrix and weight matrix corresponding to the terminal device.

In some possible implementations, the method further includes: the network device sends a second transmission signal, and each terminal device in the one or more terminal devices determines its own corresponding reception right by the second transmission signal The estimated receive weight sub-matrix corresponding to the sub-matrix. In this way, the terminal device can determine the estimated receiving weight sub-matrix corresponding to the terminal device according to the receiver type and the second received signal corresponding to the second reference signal. In this application, when performing channel estimation, the network device sends another reference signal (second reference signal) in addition to the reference signal used for direct channel estimation. This scheme of implicitly indicating the receiving weight sub-matrix through the second reference signal can avoid the signaling notification of the receiving weight matrix, reduce the downlink signaling overhead, and avoid the quantization during notification. performance loss.

Specifically, the second transmission signal is obtained by precoding the second reference signal by the network device according to the weight sub-matrix. In this way, the terminal device can estimate the estimated receiving weight sub-matrix corresponding to the terminal device according to the second reference signal.

In some other possible implementation manners, the first channel matrix

W is a receiving weight matrix, and the number of rows of the receiving weight matrix is less than or equal to the sum of the number of receiving antennas of the one or more terminal devices. In this way, the second channel matrix is dimensionally reduced by receiving the weight matrix and the weight matrix to obtain a first matrix whose dimension is less than or equal to the second channel matrix, thereby reducing the computational difficulty of channel matrix decomposition.

In some embodiments, the receiving weight matrix includes a receiving weight sub-matrix corresponding to each terminal device in the plurality of terminal devices, and the receiving weight sub-matrix corresponding to each terminal device is the network device according to the terminal device. The receiver type of the device is determined. The network device does not depend on the channel information of other users to calculate the receiving weight matrix, and does not need joint detection or notification of channel state information of other users. In this way, the terminal equipment at the receiving end can estimate the estimated receiving weight sub-matrix corresponding to the receiving weight sub-matrix corresponding to the terminal equipment in a simpler manner when detecting the signal, thereby reducing the processing complexity of the terminal equipment.

In some embodiments, the method further includes: the network device precoding the transmission data signal according to the first channel matrix to obtain a precoded transmission data signal; the network device sends the precoding After the data signal is sent. In this way, since the first transmitted signal is encoded based on the first channel matrix to encode the first reference signal, and the transmitted data signal is also precoded based on the first channel matrix, the terminal device can The equivalent channel coefficient corresponding to the terminal device is obtained from the first received signal of the terminal device, and the received data signal corresponding to the transmitted data signal is detected according to the equivalent channel coefficient.

In a third aspect, an embodiment of the present application further provides a signal transmission device, including a receiving unit and a processing unit; the signal transmission device may be, for example, a terminal device, or the signal transmission device may be deployed in the terminal device; the receiving unit is configured to receive a first received signal; the first received signal is sent to the terminal device through the downlink channel corresponding to the terminal device after precoding the first reference signal according to the first channel matrix, and the first channel matrix is based on the Obtained from the second channel matrix, the number of rows and/or columns of the first channel matrix is less than or equal to the sum of the number of receiving antennas of one or more terminal devices participating in MIMO transmission, and the second channel matrix is all The channel matrix of the downlink channel corresponding to the one or more terminal equipment; the processing unit is configured to obtain the equivalent channel coefficient corresponding to the terminal equipment according to the first received signal.

In some embodiments, the first channel matrix

W is the reception weight matrix, V is the weight matrix, and H is the second channel matrix. The number of rows of the reception weight matrix and/or the number of columns of the weight matrix is less than or equal to the number of the participating MIMO transmission. The sum of the number of receive antennas of one or more terminal devices.

In some embodiments, the number of rows of the receiving weight matrix is the sum of the number of transport streams of the one or more terminal devices, and/or the number of columns of the weight matrix is the number of the plurality of terminal devices The sum of the number of transport streams.

In some embodiments, the receiving weight matrix includes a receiving weight sub-matrix corresponding to the terminal device; the receiving unit is further configured to receive a second received signal;

The processing unit is also used to:

According to the first received signal, obtaining the equivalent channel coefficient corresponding to the terminal device includes:

determining an estimated receiving weight sub-matrix corresponding to the receiving weight sub-matrix according to the second received signal; and

Equivalent channel coefficients corresponding to the terminal equipment are obtained according to the estimated receiving weight sub-matrix and the first received signal.

In some embodiments, the weight matrix includes a weight sub-matrix corresponding to the terminal device, and the second received signal is obtained after the network device precodes the second reference signal according to the weight sub-matrix, It is sent to the terminal device through the downlink channel corresponding to the terminal device.

In some embodiments, the first channel matrix

W is a receiving weight matrix, and the number of rows of the receiving weight matrix is less than the sum of the number of receiving antennas of the one or more terminal devices participating in the MIMO transmission.

In some embodiments, the number of rows of the reception weight matrix is the sum of the number of transport streams of the plurality of terminal devices.

Processing units are also used to:

In some implementations, the receiving unit is further configured to receive a first received data signal, where the first received data signal is a network device that precodes the transmitted data signal according to the first channel matrix and passes through the terminal device. The corresponding downlink channel is sent to the terminal device; the processing unit is further configured to detect the first received data signal according to the estimated receiving weight sub-matrix and the equivalent channel coefficient corresponding to the terminal device.

In some embodiments, in terms of detecting the data signal according to the estimated receiving weight sub-matrix and the equivalent channel coefficient corresponding to the terminal device, the processing unit is specifically configured to:

Left-multiplying the first received data signal by the estimated receiving weight sub-matrix to obtain a second received data signal corresponding to the first received data signal;

The estimation result of the transmitted data signal is obtained according to the second received data signal and the equivalent channel coefficient corresponding to the terminal device.

In some embodiments, the signal transmission apparatus further includes: a sending unit, configured to send a receiver type of the terminal device, where the receiver type of the terminal device is used by the network device to determine the reception weight matrix.

It should be understood that the technical effects and related supplementary descriptions of the various embodiments of the signal transmission method of the first aspect are also applicable to the signal transmission device of the third aspect of the present application, and the description will not be repeated here.

In a fourth aspect, embodiments of the present application further provide a signal transmission device for multiple-input multiple-output MIMO transmission, including a processing unit and a sending unit; the signal transmission device may be, for example, a network device, or the signal transmission device may be deployed in network equipment; wherein the processing unit is configured to precode the first reference signal according to the first channel matrix to obtain the first transmission signal, the first channel matrix is obtained according to the second channel matrix, and the value of the first channel matrix is The number of rows and/or columns is less than or equal to the sum of the number of receiving antennas of one or more terminal devices participating in the MIMO transmission, and the second channel matrix is the channel matrix of the downlink channel of the one or more terminal devices; The sending unit is used for sending the first sending signal.

In the technical solution of the present application, the signal transmission apparatus precodes the first reference signal according to the first channel matrix, the first channel matrix is obtained according to the second channel matrix, and the number of rows and/or columns of the first channel matrix is less than Or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission, so that the difficulty of matrix calculation can be reduced in the process of THP precoding, and the calculation of THP precoding can be made simpler.

In some embodiments, the first channel matrix

W is a receiving weight matrix, V is a weight matrix, and the number of rows of the receiving weight matrix and/or the number of columns of the weight matrix is less than or equal to the sum of the number of receiving antennas of the one or more terminal devices.

In some embodiments, the number of rows of the reception weight matrix is the sum of the number of transport streams of the one or more terminal devices, and/or the number of columns of the weight matrix is the number of the one or more terminals The number of transport streams for the device.

In some embodiments, the weight matrix includes a weight sub-matrix corresponding to each terminal device in the one or more terminal devices, and the weight sub-matrix corresponding to each terminal device is based on the corresponding weight sub-matrix of the terminal device. The channel matrix of the downlink channel is determined.

In some embodiments, the sending unit is further configured to send a second sending signal, and in the second sending signal, each terminal device in the one or more terminal devices determines the corresponding receiving weight sub-matrix corresponding to itself. The estimated receiver weight submatrix of .

In some embodiments, the second transmission signal is obtained by precoding the second reference signal by the network device according to the weight sub-matrix.

In some embodiments, the first channel matrix

W is a receiving weight matrix, and the number of rows of the receiving weight matrix is less than or equal to the sum of the number of receiving antennas of the one or more terminal devices.

In some embodiments, the receiving weight matrix includes a receiving weight sub-matrix corresponding to each terminal device in the plurality of terminal devices, and the receiving weight sub-matrix corresponding to each terminal device is the network device according to the terminal device. The receiver type of the device is determined.

In some embodiments, the processing unit is further configured to perform precoding on the transmission data signal according to the first channel matrix to obtain a precoded transmission data signal; the transmission unit is further configured to send the precoded transmission data Signal.

It should be understood that the technical effects and related supplementary descriptions of the various embodiments of the signal transmission method of the second aspect are also applicable to the signal transmission device of the fourth aspect of the present application, and the description will not be repeated here.

In a fifth aspect, the present application provides a communication device, which is a terminal device or a network device, and includes a processor and a memory, the memory is used to store computer instructions, and the processor executes the computer program or instructions in the memory, so that the above-mentioned No. The method of any one of the embodiments of one aspect or the second aspect above is performed.

In a sixth aspect, the present application further provides a communication device, the communication device includes a processor, a memory, and a transceiver, where the transceiver is used for receiving signals or sending signals; the memory is used for storing program codes; The calling program code performs the method of the first aspect or the second aspect. The memory is used to store computer programs or instructions, the processor is used to call and run the computer programs or instructions from the memory, and when the processor executes the computer programs or instructions in the memory, the communication device is made to perform the first aspect or the first aspect above. any one of the methods of the two aspects.

Optionally, there are one or more processors and one or more memories.

Optionally, the memory may be integrated with the processor, or the memory may be provided separately from the processor.

Optionally, the transceiver may include a transmitter (transmitter) and a receiver (receiver).

In a seventh aspect, the present application provides an apparatus, the apparatus includes a processor, and the processor is coupled to a memory, and when the processor executes a computer program or instructions in the memory, the method of any one of the embodiments of the first aspect is executed. Optionally, the apparatus further includes a memory. Optionally, the apparatus further includes a communication interface to which the processor is coupled.

In an implementation manner, the apparatus is a terminal device. When the communication device is a terminal device, the communication interface may be a transceiver, or an input/output interface. Optionally, the transceiver may be a transceiver circuit. Alternatively, the input/output interface may be an input/output circuit.

In another implementation, the device is a chip or a system of chips. When the device is a chip or a chip system, the communication interface may be an input/output interface, an interface circuit, an output circuit, an input circuit, a pin or a related circuit, etc. on the chip or a chip system. A processor may also be embodied as a processing circuit or a logic circuit.

In an eighth aspect, the present application provides a communication device, the communication device includes a processor and an interface circuit, the interface circuit is used to receive code instructions and transmit them to the processor; the processor runs the code instructions to execute the above-mentioned first aspect or the above-mentioned second aspect A method in any of the possible implementations of an aspect.

In a ninth aspect, the present application provides a system, where the system includes the above-mentioned terminal device and network device.

In a tenth aspect, the present application provides a computer program product, the computer program product includes: a computer program (also referred to as code, or instruction), when the computer program is run, the computer executes the above-mentioned first aspect or the above-mentioned second aspect. A method in any of the possible implementations of an aspect.

In an eleventh aspect, the present application provides a computer-readable storage medium, where the computer-readable medium stores a computer program (also referred to as code, or instruction) when it runs on a computer, so that the computer executes the above-mentioned first aspect Or the method in any possible implementation manner of the second aspect above.

In a twelfth aspect, the present application further provides a chip, including: a processor and an interface, configured to execute a computer program or instruction stored in a memory, to execute any of the possible implementations of the first aspect or the second aspect. Methods.

Description of drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the accompanying drawings required in the embodiments will be briefly introduced below.

1 is a network architecture diagram of a network system involved in an embodiment of the application;

2A is a schematic structural diagram of a communication device according to an embodiment of the present application;

2B is a schematic structural diagram of a chip according to an embodiment of the present application;

3A is a schematic diagram of a scenario of THP precoding;

3B is a schematic flowchart of THP precoding;

4 is a schematic flowchart of a signal transmission method according to an embodiment of the present application;

5A is another schematic flowchart of a signal transmission method according to an embodiment of the present application;

FIG. 5B is another schematic flowchart of a signal transmission method according to an embodiment of the present application;

5C is a schematic diagram of a scenario involved in a signal transmission method according to an embodiment of the present application;

6 is another schematic flowchart of a signal transmission method according to an embodiment of the present application;

FIG. 7 is another schematic flowchart of a signal transmission method according to an embodiment of the present application;

FIG. 8 is a schematic structural diagram of a signal transmission apparatus according to an embodiment of the present application;

FIG. 9 is another schematic structural diagram of a signal transmission apparatus according to an embodiment of the present application.

Detailed ways

The technical solutions in the present application will be described below with reference to the accompanying drawings.

The technical solutions of the embodiments of the present application can be applied to various communication systems, such as: Long Term Evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (time division duplex) , TDD), universal mobile telecommunication system (UMTS), worldwide interoperability for microwave access (WiMAX) communication system, 5G mobile communication system or new radio access technology (new radio Access Technology, NR). The 5G mobile communication system may include a non-standalone (NSA, NSA) and/or an independent network (standalone, SA).

The technical solutions provided in this application can also be applied to machine type communication (MTC), Long Term Evolution-machine (LTE-M), device-to-device (D2D) Network, machine to machine (M2M) network, internet of things (IoT) network or other network. The IoT network may include, for example, the Internet of Vehicles. Among them, the communication methods in the Internet of Vehicles system are collectively referred to as vehicle to other devices (vehicle to X, V2X, X can represent anything), for example, the V2X may include: vehicle to vehicle (vehicle to vehicle, V2V) communication, vehicle and vehicle Infrastructure (V2I) communication, vehicle to pedestrian (V2P) or vehicle to network (V2N) communication, etc.

The technical solutions provided in this application can also be applied to future communication systems, such as the sixth generation mobile communication system. This application does not limit this.

In this embodiment of the present application, the network device may be any device with a wireless transceiver function. The device includes but is not limited to: evolved Node B (evolved Node B, eNB), radio network controller (radio network controller, RNC), Node B (Node B, NB), base station controller (base station controller, BSC) , base transceiver station (base transceiver station, BTS), home base station (for example, home evolved NodeB, or home Node B, HNB), baseband unit (baseband unit, BBU), wireless fidelity (wireless fidelity, WiFi) system Access point (AP), wireless relay node, wireless backhaul node, transmission point (TP) or transmission and reception point (TRP), etc. It can also be 5G, such as NR , a gNB in the system, or, a transmission point (TRP or TP), one or a group of (including multiple antenna panels) antenna panels of a base station in a 5G system, or, it can also be a network node that constitutes a gNB or a transmission point, Such as baseband unit (BBU), or distributed unit (distributed unit, DU) and so on.

In some deployments, a gNB may include a centralized unit (CU) and a DU. The gNB may also include an active antenna unit (AAU). CU implements some functions of gNB, and DU implements some functions of gNB. For example, CU is responsible for processing non-real-time protocols and services, implementing radio resource control (RRC), and packet data convergence protocol (PDCP) layer function. The DU is responsible for processing physical layer protocols and real-time services, and implementing the functions of the radio link control (RLC) layer, medium access control (MAC) layer, and physical (PHY) layer. AAU implements some physical layer processing functions, radio frequency processing and related functions of active antennas. Since the information of the RRC layer will eventually become the information of the PHY layer, or be transformed from the information of the PHY layer, therefore, in this architecture, the higher-layer signaling, such as the RRC layer signaling, can also be considered to be sent by the DU. , or, sent by DU+AAU. It can be understood that the network device may be a device including one or more of a CU node, a DU node, and an AAU node. In addition, the CU can be divided into network devices in an access network (radio access network, RAN), and the CU can also be divided into network devices in a core network (core network, CN), which is not limited in this application.

The network equipment provides services for the cell, and the terminal equipment communicates with the cell through the transmission resources (for example, frequency domain resources, or spectrum resources) allocated by the network equipment, and the cell may belong to a macro base station (for example, a macro eNB or a macro gNB, etc.) , can also belong to the base station corresponding to the small cell, where the small cell can include: urban cell (metro cell), micro cell (micro cell), pico cell (pico cell), femto cell (femto cell), etc. , these small cells have the characteristics of small coverage and low transmission power, and are suitable for providing high-speed data transmission services.

In this embodiment of the present application, a terminal device may also be referred to as user equipment (user equipment, UE), an access terminal device, a subscriber unit, a subscriber station, a mobile station, a mobile station, a remote station, a remote terminal device, a mobile device, a user Terminal equipment, terminal equipment, wireless communication equipment, user agent or user equipment.

The terminal device may be a device that provides voice/data connectivity to the user, such as a handheld device with a wireless connection function, a vehicle-mounted device, and the like. At present, some examples of terminal equipment can be: mobile phone (mobile phone), tablet computer (pad), computer with wireless transceiver function (such as notebook computer, palmtop computer, etc.), mobile internet device (mobile internet device, MID), virtual Virtual reality (VR) equipment, augmented reality (AR) equipment, wireless terminal equipment in industrial control, wireless terminal equipment in self-driving (self driving), remote medical (remote medical) wireless terminal equipment in smart grid, wireless terminal equipment in transportation safety, wireless terminal equipment in smart city, wireless terminal equipment in smart home Wireless terminal equipment, cellular phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDA), with wireless communication capabilities handheld devices, computing devices or other processing devices connected to wireless modems, in-vehicle devices, wearable devices, end devices in 5G networks or end devices in the future evolved public land mobile network (PLMN) Wait.

Among them, wearable devices can also be called wearable smart devices, which is a general term for the intelligent design of daily wear and the development of wearable devices using wearable technology, such as glasses, gloves, watches, clothing and shoes. A wearable device is a portable device that is worn directly on the body or integrated into the user's clothing or accessories. Wearable device is not only a hardware device, but also realizes powerful functions through software support, data interaction, and cloud interaction. In a broad sense, wearable smart devices include full-featured, large-scale, complete or partial functions without relying on smart phones, such as smart watches or smart glasses, and only focus on a certain type of application function, which needs to cooperate with other devices such as smart phones. Use, such as all kinds of smart bracelets, smart jewelry, etc. for physical sign monitoring.

In addition, the terminal device may also be a terminal device in an internet of things (Internet of things, IoT) system. IoT is an important part of the development of information technology in the future. Its main technical feature is to connect items to the network through communication technology, so as to realize the intelligent network of human-machine interconnection and interconnection of things. IoT technology can achieve massive connections, deep coverage, and power saving of terminal devices through, for example, narrowband NB technology.

In addition, terminal equipment can also include sensors such as smart printers, train detectors, and gas stations. The main functions include collecting data (part of terminal equipment), receiving control information and downlink data of network equipment, and sending electromagnetic waves to transmit uplink data to network equipment. .

To facilitate understanding of the embodiments of the present application, a communication system applicable to the methods provided by the embodiments of the present application is first described in detail with reference to FIG. 1 . FIG. 1 shows a schematic diagram of a communication system applicable to the method provided by this embodiment of the present application. As shown in the figure, the communication system may include at least one network device; the communication system may also include at least one terminal device. Wherein, the terminal equipment in the communication system may be mobile or fixed. Network devices and end devices can communicate over wireless links. Each network device can provide communication coverage for a specific geographic area and can communicate with terminal devices located within that coverage area. For example, the network device may send configuration information to the terminal device, and the terminal device may send uplink data to the network device based on the configuration information; for another example, the network device may send downlink data to the terminal device. Therefore, the network device and the terminal device in FIG. 1 constitute a communication system.

Optionally, the terminal devices may also communicate with network devices respectively. Direct communication between end devices is possible.

It should be understood that FIG. 1 exemplarily shows a network device, a plurality of terminal devices, and communication links between the communication devices. Optionally, the communication system may include multiple network devices, and the coverage of each network device may include other numbers of terminal devices, such as more or less terminal devices. This application does not limit this.

Each of the above communication devices, such as the network device and the terminal device in FIG. 1 , may be configured with multiple antennas. The plurality of antennas may include at least one transmit antenna for transmitting signals and at least one receive antenna for receiving signals. In addition, each communication device additionally includes a transmitter chain and a receiver chain, which can be understood by those of ordinary skill in the art, all of which may include multiple components (eg, processors, modulators, multiplexers) related to signal transmission and reception. , demodulator, demultiplexer or antenna, etc.). Therefore, the network device and the terminal device can communicate through the MIMO technology.

Optionally, the wireless communication system may further include other network entities such as a network controller, a mobility management entity, and the like, which are not limited in this embodiment of the present application.

The related functions of the terminal device and the network device in the embodiments of the present application may be implemented by the communication apparatus 200 in FIG. 2A . FIG. 2A is a schematic structural diagram of a communication device according to an embodiment of the present application. As shown in FIG. 2A , the communication apparatus 200 may include: a processor 201 , a transceiver 205 , and optionally a memory 202 .

The transceiver 205 may be referred to as a transceiver unit, a transceiver, or a transceiver circuit, etc., for implementing a transceiver function. The transceiver 205 may include a receiver and a transmitter, the receiver may be called a receiver or a receiving circuit, etc., for implementing a receiving function; the transmitter may be called a transmitter or a transmitting circuit, etc., for implementing a transmitting function.

Stored in memory 202 may be a computer program or software code or instructions 204, which may also be referred to as firmware. The processor 201 can control the MAC layer and the PHY layer by running the computer program or software code or instruction 203 therein, or by calling the computer program or software code or instruction 204 stored in the memory 202, so as to realize the following aspects of the present application. The signal transmission method provided by the embodiment. Wherein, the processor 201 can be a central processing unit (central processing unit, CPU), and the memory 202 can be, for example, a read-only memory (read-only memory, ROM), or a random access memory (random access memory, RAM).

The processor 201 and transceiver 205 described in this application may be implemented in integrated circuits (ICs), analog ICs, radio frequency integrated circuits (RFICs), mixed-signal ICs, application specific integrated circuits (ASICs), printed circuits board (printed circuit board, PCB), electronic equipment, etc.

The above-mentioned communication apparatus 200 may further include an antenna 206, and each module included in the communication apparatus 200 is only for illustration, which is not limited in this application.

As mentioned above, the communication apparatus 200 described in the above embodiments may be network equipment or terminal equipment, but the scope of the communication apparatus described in this application is not limited thereto, and the structure of the communication apparatus may not be limited by FIG. 2A . The communication apparatus may be a stand-alone device or may be part of a larger device. For example, the implementation form of the communication device may be:

(1) Independent integrated circuit IC, or chip, or, chip system or subsystem; (2) A set of one or more ICs, optionally, the IC set may also include storage for storing data and instructions components; (3) modules that can be embedded in other devices; (4) receivers, smart terminals, wireless devices, handsets, mobile units, in-vehicle devices, cloud devices, artificial intelligence devices, etc.; (5) others, etc. .

For the case where the implementation form of the communication device is a chip or a chip system, reference may be made to the schematic structural diagram of the chip shown in FIG. 2B . The chip shown in Figure 2B includes a processor and an interface. The number of processors may be one or more, and the number of interfaces may be multiple. Interfaces are used for signal reception and transmission. Optionally, the chip or chip system may include memory. The memory is used to store the necessary program instructions and data of the chip or chip system.

The examples of this application do not limit the protection scope and applicability of the claims. Those skilled in the art may make adaptive changes to the functions and deployment of the elements involved in the present application, or omit, substitute or add various processes or components as appropriate, without departing from the scope of the embodiments of the present application.

As shown in FIG. 3A , the processing block diagram of THP precoding, THP precoding includes a process of nonlinear precoding and a process of linear precoding. Based on the scenario that the number of transmit antennas is equal to the total number of receive antennas of all terminal devices participating in MIMO transmission, and equal to the total number of transmission streams L of all users, the process of THP precoding is described. As shown in the schematic flowchart of FIG. 3B, in the related art, the process of THP precoding includes the following steps:

301. The network device performs interference cancellation and modulo calculation on the transmitted modulation symbol vector based on the feedback matrix to obtain the transmitted symbol vector.

It should be understood that the above interference cancellation and modulo calculation can also be other similar operations or equivalent operations, and step 301 can also be understood as a process of nonlinear precoding.

For example, assuming that n terminal devices participate in MIMO transmission, the n terminal devices may be denoted as terminal device 1, terminal device 2, . . . , terminal device n.

A terminal device participating in MIMO transmission may be a terminal device participating in pairing, or a terminal device participating in multi-user MU-MIMO transmission.

For example, the terminal device k can be understood as the kth terminal device, k=1, 2, ..., n. Each terminal device corresponds to the transmitted symbol vector

Wherein L _k represents the number of transmitted transport streams corresponding to terminal device k. s _k,l (l∈[1,L _k ]) represents the symbol sent by the lth transport stream corresponding to terminal device k. In the nonlinear processing stage, the network device performs interference cancellation on the multi-user transmitted symbol vector s=(s ₁ , s ₂ ,...,s _n ) ^T , and performs a modulo operation after the interference cancellation operation to avoid the interference cancellation operation. This results in unlimited transmit power.

After the modulo operation, the network device obtains the transmitted symbol vector x=(x ₁ , x ₂ , . . . , x _n ) ^T . The total number of transmitted transport streams corresponding to n terminal devices is

Each element in the multi-user transmitted symbol vector s can be re-indexed, denoted as s=(s ₁ , s ₂ , . . . , s _L ) ^T . Similarly, each element in the transmitted symbol vector x is rearranged and denoted as x=(x ₁ , x ₂ , . . . , x _L ) ^T .

Specifically, the feedback matrix B can be expressed as B=GR ^H . The dimension of the feedback matrix B is L×L.

where the R matrix passes through the complete channel matrix for all users

QR decomposition of the conjugate transposed matrix can be obtained: H ^H =QR. where H _k represents the channel matrix corresponding to terminal device k, and the dimension is

represents the number of receiving antennas of the terminal device k, and _NT represents the number of transmitting antennas of the network device.

The G matrix is a diagonal matrix of dimension L×L, and its main diagonal element is the reciprocal of the main diagonal element of the R matrix, that is,

where r _kk represents the element corresponding to the k-th row and the k-th column of the R matrix. Matrix B is a lower triangular matrix with elements on the main diagonal of 1. The matrix Q is a unitary matrix of dimension L×L.

For the kth spatial layer composed of n terminal devices, the transmission symbol x _k output after the network device performs interference cancellation and modulo calculation on the transmission modulation symbol vector can be expressed as:

where B _k,l represents the element corresponding to the k-th row and the l-th column of the B matrix. Mod _τ {x} represents the modulo operation, and the modulo operation parameter is τ.

Used to power constrain the transmitted symbols after nonlinear operation. d _k represents the rounded part obtained by modulo operation of the kth space layer. In this application, one spatial layer corresponds to one transport stream.

Through the above nonlinear operations, the obtained transmitted symbol vector can be expressed as:

x = B ^-1 v;

Wherein, v=(v ₁ , v ₂ , . . . , v _L ) ^T , v _k =s _k +d _k τ . k=1,2,...,L.

302. The network device performs linear precoding on the transmitted symbol vector x to obtain a precoded transmitted symbol vector.

Specifically, the network device performs linear precoding on the transmitted symbol vector x by using the matrix Q to obtain the precoded transmitted symbol vector

β is the power normalization factor. The power normalization factor in this embodiment of the present application may also be a power adjustment factor, a power control factor, or a power factor. The power factor can be 1, or a real number greater than 1 or less than 1.

The signal received by one or more terminal devices participating in MIMO transmission can be represented as

where n is additive white Gaussian noise, sum or interference.

y=(y ₁ , y ₂ ,...,y _n ) ^T , y _k represents the received symbol vector corresponding to terminal device k,

y _k,l represents the received signal corresponding to the lth receiving antenna of terminal device k. The G matrix is a diagonal matrix. Therefore, through THP precoding, the multi-user multi-antenna channel can be converted into parallel sub-channels, and the received signal corresponding to the u-th terminal device can be expressed as

in,

is the sub-matrix corresponding to the u-th terminal device in matrix G ^-1 ,

The transport stream corresponding to the u-th spatial layer of terminal equipment k, the corresponding equivalent channel coefficient is

is a matrix

Elements located on the main diagonal in the row corresponding to the u-th spatial layer of terminal device k.

The terminal device may use a demodulation reference signal (DMRS) sent by the network device to perform channel estimation to obtain equivalent channel coefficients

Based on the above introduction about THP precoding, THP precoding depends on the channel matrix

The QR decomposition of H ^H = QR. Among them, the Q matrix is a unitary matrix of N _T × N _T , and the R matrix is

the triangular matrix. On the other hand, the dimension of the feedback matrix B used by the network device for serial interference cancellation in the nonlinear precoding stage should be L×L. When the total number of transmission streams of n terminal devices participating in MIMO transmission

Less than the total number of receiving antennas of multiple terminal devices

When , due to the mismatch of matrix dimensions, the feedback matrix B cannot directly obtain a square matrix of dimension L×L through B=GR ^H. n is the number of terminal devices participating in MIMO transmission.

In the related art, the solution to the above-mentioned problem of matrix dimension mismatch is to select L row vectors in the R matrix to form a new matrix

Correspondingly, select L corresponding column vectors in the Q matrix to form a new matrix

Matrix after row/column selection

and

Do THP precoding.

In such a scheme, in the case of a large number of transmitting antennas,

The value of is also larger, and the QR decomposition of the channel matrix H has a higher complexity. In addition, the total number of transport streams for n terminal devices

Less than the total number of receiving antennas of multiple terminal devices

When the signal is received by some receiving antennas, there will be strong inter-user interference and inter-stream interference, which will affect the detection performance of the receiving end.

The embodiment of the present application provides a signal transmission method for MIMO transmission.

As shown in the schematic flowchart shown in FIG. 4 , the signal transmission method according to the embodiment of the present application includes:

401. According to the first channel matrix, the network device

Perform precoding on the first reference signal s ₁ to obtain the first transmitted signal x ₁ ;

first channel matrix

is obtained according to the second channel matrix H, the first channel matrix

The number of rows and/or columns is less than or equal to the sum of the number of receiving antennas of one or more terminal devices participating in MIMO transmission, and the second channel matrix H is a channel matrix of downlink channels of multiple terminal devices.

In this embodiment of the present application, the terminal device participating in MIMO transmission may also be a terminal device participating in pairing, or a terminal device participating in multi-user MU-MIMO transmission.

The MIMO system includes n terminal devices, which are terminal device 1, terminal device 2, ..., and terminal device n respectively. The terminal device k may also be understood as the kth terminal device. k=1, 2, ..., n.

The sum of the total number of transport streams of n terminal devices is

first channel matrix

The number of rows and columns is greater than or equal to L.

Optionally, the second channel matrix H is a block matrix. The second channel matrix H includes a channel matrix of downlink channels corresponding to each of the n terminal devices participating in the MIMO transmission. second channel matrix

The dimension of the second channel matrix H is

or the second channel matrix

The dimension of the second channel matrix H is

represents the number of receiving antennas of the terminal device k, and _NT represents the number of transmitting antennas of the network device. The element in the ith row and the jth column of H _k represents the channel coefficient between the ith receiving antenna of the terminal device k and the jth sending antenna pair of the network device.

For example, the second channel matrix

It includes multiple sub-matrices, the multiple sub-matrices include the second channel matrix H ₁ of the downlink channel corresponding to the terminal device 1, the channel matrix H ₂ of the downlink channel corresponding to the terminal device 2, ..., the channel of the downlink channel corresponding to the terminal device n matrix H _n .

The first transmission signal x ₁ may be a transmission signal vector corresponding to the first reference signal symbols corresponding to the n terminal devices after precoding. The first reference signal corresponding to the terminal device k

The first reference signal symbols corresponding to the L _k ports are included. in,

Indicates the first reference signal symbol corresponding to the lth port of the kth terminal device. Each reference signal port corresponds to a spatial layer. The first reference signals corresponding to different ports may be orthogonal signals. The first reference signal symbols corresponding to different ports may be multiplexed by one or more of time division multiplexing, frequency division multiplexing and code division multiplexing. The network device may send first transmit signals corresponding to multiple first reference signals, or in other words, may transmit first transmit signals corresponding to multiple first reference signal symbols. Multiple first reference signals may occupy different time-frequency resources. It can be understood that the n terminal devices are terminal devices participating in MIMO transmission.

Specifically, the network device according to the first channel matrix

For the first reference signals corresponding to n terminal devices

Perform precoding to obtain the first transmission signal corresponding to n terminal devices

Indicates the first transmit signal corresponding to the lth transmit antenna. The first reference signal corresponding to terminal device k is

The first reference signal may be a demodulation reference signal (DMRS).

402. The network device sends the first sending signal x ₁ ;

The first transmit signal x ₁ is the transmit signal corresponding to the n terminal devices participating in the MIMO transmission; x ₁ satisfies

403. Terminal device k receives a first received signal corresponding to terminal device k

the first received signal

It may be that the _first transmission signal x1 is sent to the terminal equipment k through the downlink channel corresponding to the terminal equipment k.

It can be understood that the first received signal received by n terminal devices participating in MIMO transmission can be jointly expressed as

in,

Satisfy

where n _k is additive noise, sum or interference.

404. The terminal device k receives the signal according to the first

Determine the equivalent channel coefficient corresponding to the terminal device k.

The equivalent channel coefficient corresponding to the terminal device k can be used by the terminal device k to perform data detection on the data signal received via the downlink channel corresponding to the terminal device k.

In the technical solution of the present application, the network device according to the first channel matrix

Precoding the first reference signal _s1 , the first channel matrix

is obtained according to the second channel matrix H, the first channel matrix

The number of rows and/or columns is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission, thereby reducing the difficulty of matrix calculation in the process of THP precoding and making the calculation of THP precoding simpler .

Specifically, the first channel matrix

is obtained by processing the second channel matrix H by using a dimensionality reduction matrix. The dimension reduction matrix includes a receiving weight matrix W and a weight value matrix V; or the dimension reducing matrix includes a receiving weight matrix W.

In this application, the weight matrix may be an outer weight matrix.

It should be understood that the precoding in this embodiment of the present application may be THP precoding, or may be other precoding technologies. For example, the precoding may be, but not limited to, symbol level precoding (SLP), vector perturbation (VP) precoding, zero-forcing (zero-forcing) precoding, and the like.

In one possible implementation, the second channel matrix

first channel matrix

In another possible implementation, the second channel matrix

first channel matrix

The signal transmission scheme in the scenario where the dimensionality reduction matrix includes the receiving weight matrix W and the outer layer weight matrix V, and the signal transmission scheme in the scenario where the dimensionality reduction matrix includes the receiving weight matrix W are described in detail below.

1. The signal transmission scheme in the scenario where the dimensionality reduction matrix includes the receiving weight matrix W and the weight matrix V.

In some possible implementations, the first channel matrix

second channel matrix

The number of rows of the receiving weight matrix W is less than or equal to the sum of the number of receiving antennas of the n terminal devices participating in the MIMO transmission. That is, the first channel matrix

The number of rows is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission. Or the number of rows of the receiving weight matrix W and the number of columns of the weight matrix V are both less than or equal to the sum of the number of receiving antennas of the n terminal devices participating in the MIMO transmission, that is, the first channel matrix

In some other possible implementations, the first channel matrix

second channel matrix

The number of columns of the weight matrix V is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission, that is, the first channel matrix

The number of columns is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission. Or the number of rows of the receiving weight matrix W and the number of columns of the weight matrix V are both less than or equal to the sum of the number of receiving antennas of the n terminal devices participating in the MIMO transmission, that is, the first channel matrix

The weight matrix V includes a weight sub-matrix V _k corresponding to each of the multiple terminal devices, the weight matrix V=[V ₁ . . . V _n ], and the dimension of the weight matrix V is N _T ×L. The dimension of the weight sub-matrix V _k of the terminal device k is N _T ×L _k . L _k is the number of transport streams of terminal equipment k, k=1, 2, ..., n. The weight sub-matrix V _k is determined by the network device according to the channel matrix H _k of the downlink channel of the terminal device k. n is the number of terminal devices participating in MIMO transmission. If the weight matrix is an outer weight matrix, the outer weight matrix may include an outer weight sub-matrix corresponding to each terminal device. In other words, the weight sub-matrix may be an outer weight sub-matrix.

For example, for the weight sub-matrix V _k corresponding to the terminal equipment k, the network equipment can perform singular value decomposition (SVD) on the channel matrix H _k of the downlink channel of the terminal equipment k, that is,

Among them, U _k is the dimension

The unitary matrix of , V _k is a unitary matrix of dimension N _T × N _T , D _k is a diagonal matrix, and its main diagonal elements are the singular values corresponding to H _k .

The matrix formed by the L _k right eigenvectors corresponding to the largest L _k singular values in V _k is used as the weight sub-matrix V _k . Or the covariance matrix of the channel matrix of the downlink channel of the network device to the terminal device k

Eigenvalue decomposition (EVD) is performed, i.e.

V _k is a unitary matrix of dimension N _T × N _T , Λ _k is a diagonal matrix, and its main diagonal elements are the eigenvalues corresponding to H _k . A matrix composed of L _k right eigenvectors corresponding to the largest L _k eigenvalues in V _k is used as a weight sub-matrix V _k .

The receiving weight matrix W includes the receiving weight sub-matrices W ₁ , W ₂ , . . . , W _n corresponding to each of the n terminal equipments, wherein the receiving weight matrix W is a block diagonal matrix,

k=1,2,...,n, the dimension is

The kth sub-matrix corresponding to the main diagonal of the receiving weight matrix W is the receiving weight sub-matrix W k corresponding to the terminal device _k . The receiving weight sub-matrix W _k corresponding to the terminal device k is determined by the network device according to the receiver type of the terminal device k and the weight sub-matrix V _k corresponding to the terminal device k. Algebraically, it can be expressed as W _k =f(H _k V _k ). Wherein, f(H _k V _k ) represents corresponding processing based on H _k V _k . The corresponding processing can be a linear processing method or a nonlinear processing method.

The dimension of W _n is

The reception matrix W is a block diagonal matrix, and the sub-matrix on the diagonal is the reception weight matrix corresponding to each terminal device in the terminal device 1 to the terminal device n. The terminal device k may be understood as any one of the n terminal devices participating in the MIMO transmission.

For example, if the type of receiver sent by the terminal equipment is an MRC receiver, W _k =(H _k V _k ) ^H . If the type of receiver sent by the terminal equipment is an MMSE receiver, W _k =[(H _k V _k ) ^H (H _k V _k )+σ ² I] ^-1 (H _k V _k ) ^H . where I is the identity matrix. σ ² is an adjustment factor, which is related to the transmitted signal power and/or noise power.

In this way, the calculation of the receiving weight matrix by the network device only depends on the channel matrix H _k and the weight sub-matrix V _k corresponding to each terminal device, and does not depend on the channel information of other users, and does not require joint detection or other user channel state information (channel state information). information, CSI) notification. In this way, the terminal equipment at the receiving end can estimate the estimated receiving weight sub-matrix W _k corresponding to the receiving weight sub-matrix W _k corresponding to the terminal equipment in a simpler manner when detecting signals, thereby reducing the processing complexity of the terminal equipment.

In the scenario where the dimensionality reduction matrix includes the receiving weight matrix W and the weight matrix V, in the channel estimation stage, the network device is based on the first channel matrix

Linear precoding is performed on the reference signal to obtain the transmitted signal, and the transmitted signal is sent to the terminal equipment participating in the MIMO transmission, and the terminal equipment participating in the MIMO transmission receives the received signal transmitted through the downlink channel corresponding to the terminal equipment. The estimated receiving weight sub-matrix W′ _k performs channel estimation on the received signal, and obtains the equivalent channel parameters corresponding to the terminal equipment.

In the transmission phase of the data signal, taking THP precoding as an example, the network device first uses the first channel matrix

The obtained feedback matrix B performs nonlinear precoding on the transmitted data signals corresponding to one or more terminal devices to eliminate interference to obtain a precoded transmitted data signal, and then performs linear precoding on the transmitted data symbols based on the weight matrix V to obtain The precoded transmission data signal c. The receiving end receives the precoded transmission data signal c and transmits the corresponding received data signal through the downlink channel of the terminal device, and estimates the receiving weight sub-matrix _W'k corresponding to the terminal device and the equivalent channel corresponding to the terminal device. parameter to detect the received data signal.

Optionally, the first channel matrix

The number of rows and/or columns is the sum L of the number of transport streams of multiple terminal devices.

For example, the channel matrix

first channel matrix

The number of rows is the sum of the number of transport streams of multiple terminal devices L or the first channel matrix

The number of rows and columns of is the sum L of the number of transport streams of multiple terminal devices. For another example, the channel matrix

first channel matrix

The number of columns is the sum of the number of transport streams of multiple terminal devices L or the first channel matrix

The number of rows and columns of is the sum L of the number of transport streams of multiple terminal devices.

The following is the first channel matrix

As an example, the technical solution of the signal transmission method of the present application is described in the scenario where the dimensionality reduction matrix includes the receiving weight matrix W. Specifically, as shown in the schematic flowchart of FIG. 5A, in a specific embodiment, the signal transmission method includes the following steps:

501. The network device precodes the first reference signal s ₁ according to the matrix Q and the weight matrix V to obtain the first transmission signal x ₁ ;

The Q matrix is the network device based on the first channel matrix

obtained by QR decomposition,

The Q matrix is a unitary matrix. The R matrix is an upper triangular matrix.

first channel matrix

The number of rows and/or columns is less than or equal to the sum of the number of receive antennas of the n terminal devices participating in the MIMO transmission.

For example, the first channel matrix

The number of rows and columns of can be the sum L of the number of transport streams of multiple terminal devices, the dimension of Q is L×L, and the dimension of R is L×L. The first channel matrix after dimensionality reduction in this way

It is a square matrix, which avoids the problem of mismatching matrix dimensions when the number of transmission streams L is less than the total number of receiving antennas, and can flexibly adapt to various antenna configurations and transmission scenarios.

In one possible implementation,

α is the power control factor. The network device precodes the first reference signal s ₁ corresponding to the n terminal devices participating in the MIMO transmission according to the matrix Q and the weight matrix V, to obtain the first transmitted signal x ₁ .

Indicates the first transmitted signal symbol corresponding to the lth transmit antenna. First reference signals corresponding to n terminal devices

The first reference signal corresponding to the terminal device k

Contains the first reference signal symbols corresponding to the L _k ports,

Indicates the first reference signal symbol corresponding to the lth port of the kth terminal device. Each reference signal port corresponds to a spatial layer. The first reference signals corresponding to different ports may be orthogonal signals. The first reference signal symbols corresponding to different ports may be multiplexed by one or more of time division multiplexing, frequency division multiplexing and code division multiplexing.

The network device may transmit multiple first reference signals, or may transmit multiple first reference signal symbols. Multiple first reference signals may occupy different time-frequency resources. The terminal device k is any one of the n terminal devices participating in the MIMO transmission. If the first reference signal corresponding to each terminal equipment is an orthogonal signal, the first transmission signal corresponding to terminal equipment k

It can be expressed as:

where P _k represents the matrix VQ in

The matrix formed by the corresponding column vectors has dimension N _T ×L _k .

In another possible implementation,

Wherein, the matrix B can be expressed as B=GR ^H , the G matrix is a diagonal matrix. For example, the first channel matrix

The number of rows and columns can be the sum of the number of transport streams of multiple terminal devices, L, the G matrix is a diagonal matrix with dimension L×L, and its main diagonal elements are the main diagonal elements of the R matrix. reciprocal, i.e.

The dimension of matrix B is L×L. α is the power control factor.

The network device precodes the first reference signal s ₁ corresponding to the n terminal devices participating in the MIMO transmission according to the matrix Q, the matrix B and the weight matrix V to obtain the first transmitted signal x ₁ .

The first reference signal corresponding to the terminal device k

Contains the first reference signal symbols corresponding to the L _k ports,

Indicates the first reference signal symbol corresponding to the lth port of the kth terminal device.

If the first reference signal corresponding to each terminal equipment is an orthogonal signal, the first transmission signal corresponding to terminal equipment k

It can be expressed as:

where P _k represents the matrix VQB ^-1

502. The network device sends a first sending signal x ₁ .

503. The terminal device k receives the first received signal corresponding to the terminal device k

The first received signal y ₁ corresponds to the first transmitted signal x ₁ . in the above

In the implementation manner of , the first received signal received by n terminal devices participating in MIMO transmission can be expressed as

where n is additive white Gaussian noise and or interference, where,

is the first received signal corresponding to the terminal device k, k=1, 2, ..., n.

second channel matrix

The first received signals corresponding to n terminal devices participating in MIMO transmission:

For convenience, define

Then the first received signal corresponding to the kth terminal device

where n _k is the additive white Gaussian noise sum or interference corresponding to terminal device k,

in the above

where n is additive white Gaussian noise, where,

second channel matrix

For convenience, define

Then the first received signal corresponding to the kth terminal device

n _k is additive white Gaussian noise and or interference.

504. The terminal equipment k determines the estimated receiving weight sub-matrix W' k corresponding to the receiving weight sub-matrix W _k corresponding to the terminal equipment _k ;

For example, the terminal device k may determine the reception weight sub-matrix W _k according to the second received signal corresponding to the second transmission signal sent by the network device; or, the terminal device k may also determine the reception weight sub-matrix W _k in a manner agreed with the network device The corresponding estimated receive weight submatrix W' _k . The estimated receiving weight sub-matrix W' _k can be understood as an estimated matrix of the receiving weight sub-matrix W _k .

It can be understood that step 504 may be performed after step 503 or may be performed before step 503 .

505. Terminal equipment k estimates the first received signal corresponding to terminal equipment k according to the estimated receiving weight sub-matrix W' _k

The equivalent channel coefficient corresponding to the terminal equipment k is obtained.

Specifically, the terminal device k can use the estimated receiving weight sub-matrix W′ _k to left-multiply the first received signal

Obtain the third received signal corresponding to the first received signal

Terminal device k receives the signal according to the third

The first reference signal corresponding to terminal equipment k

For example, based on the above

The implementation manner of , the third received signal corresponding to the terminal device k

The corresponding third received signal of the corresponding terminal equipment 1-terminal equipment n:

Among them, n _k and n' are additive white Gaussian noise.

Estimating the receiving weight matrix

The estimated receiving weight matrix W' can be understood as an estimated matrix of the receiving weight matrix W. The estimated receiving weight matrix W' can be equivalent to the receiving weight matrix W superimposed on the channel estimation error matrix, that is, W'=W+ _ΔW . The estimated receiving weight matrix W' is a block diagonal matrix, and W' includes estimated receiving weight sub-matrices W' ₁ , W' ₂ corresponding to W ₁ , W ₂ , ..., W _n included in the receiving weight matrix W, respectively, ..., _W'n . In an ideal case, assuming W′=W, the above formula can be expressed as

When there is a channel estimation error,

where the R matrix is the matrix for the first channel

obtained by QR decomposition,

In this way, the network device uses the first channel matrix for precoding

is obtained according to the receiving weight sub-matrix W _k , and the terminal device multiplies the first received signal by left-multiplying the estimated receiving weight matrix _W'k

Received data received signal

Determine the equivalent channel coefficients. Both the network equipment and the terminal equipment operate and process according to the same receiver assumption to ensure the matching calculated by the sender and the receiver. The reporting or downlink notification of the detection weight matrix can be avoided.

It is estimated that the dimension of the receiving weight matrix W' is the same as that of the receiving weight matrix W. It is estimated that the values of the elements in the receiving weight matrix W' and the elements in the same position of the receiving weight matrix W may be the same or close.

R ^H is the lower triangular matrix, R matrix is the first channel matrix

It is obtained by QR decomposition. The elements located on the main diagonal in each row of ^RH correspond to the equivalent channel coefficients of a transport stream. The equivalent channel coefficients can be used to detect data transmitted by the transport stream.

The terminal device k receives the third signal corresponding to the terminal device k through

Perform channel estimation to obtain equivalent channel coefficients corresponding to one or more transport streams corresponding to terminal device k.

For example, if the number of transmission streams corresponding to terminal equipment k is m, then terminal equipment k can receive signals through the third receiving signal corresponding to terminal equipment k.

Perform channel estimation. The first reference signal corresponding to terminal device k

The terminal equipment k and the network equipment at both ends of the transceiver are known, and the terminal equipment k can receive the signal according to the third

In ^RH , the main diagonal elements on the m rows corresponding to the terminal device k are obtained, and the diagonal elements on the m rows are the equivalent channel coefficients corresponding to the m transport streams respectively. In an implementation manner, if the first reference signal corresponding to each terminal device is an orthogonal signal, the third received signal corresponding to terminal device k

It can be expressed as

in

express

A sub-matrix consisting of elements corresponding to the row and column corresponding to terminal device k.

The terminal device k can receive the signal through the third corresponding to the terminal device k

Based on the first reference signal

Perform channel estimation to get the estimation result

where the l-th main diagonal element is the equivalent channel coefficient corresponding to the l-th data stream corresponding to the terminal device k.

The terminal device k can detect the data signal transmitted by each transport stream according to the equivalent channel coefficient corresponding to the transport stream.

For another example, based on the above

Among them, n and n' are additive white Gaussian noise.

Estimating the receiving weight matrix

The estimated receiving weight matrix W' can be understood as an estimated matrix of the receiving weight matrix W. The estimated receiving weight matrix W' can be equivalent to the receiving weight matrix W superimposed on the channel estimation error matrix, that is, W'=W+ _ΔW .

The estimated receiving weight matrix W' is a block diagonal matrix, and W' includes estimated receiving weight sub-matrices W' ₁ , W' ₂ corresponding to W ₁ , W ₂ , ..., W _n included in the receiving weight matrix W, respectively, ..., _W'n . In an ideal case, assuming W′=W, the above formula can be expressed as

When there is a channel estimation error,

The G matrix is related to the R matrix, and the R matrix is the network device according to the first channel matrix

obtained by QR decomposition,

The G matrix is a diagonal matrix, and its main diagonal element is the reciprocal of the main diagonal element of the R matrix, that is,

The third received signal corresponding to the terminal device k

or

Among them, n and n' are additive white Gaussian noise.

in,

is the submatrix corresponding to the kth terminal device in matrix G ^-1 ,

G ^-1 is a diagonal matrix, and each element on the main diagonal of G ^-1 corresponds to an equivalent channel coefficient of a transport stream. The equivalent channel coefficients can be used to detect data transmitted by the transport stream.

Perform channel estimation. first reference signal

get

There are m main diagonal elements, where the m diagonal elements are the equivalent channel coefficients corresponding to the m transport streams respectively. The transport stream corresponding to the u-th spatial layer of terminal equipment k, the corresponding equivalent channel coefficient is

is a matrix

In this way, each of the n terminal devices participating in the MIMO transmission can obtain their corresponding equivalent channel coefficients for subsequent detection of the received data signal by each device.

It can be seen that in the technical solution of the present application, the dimension of the channel matrix can be reduced, so that the first channel matrix

The number of rows and/or columns is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission. By designing the weight matrix V and the receiving weight matrix W reasonably, the first channel matrix can be

The number of rows and columns are the sum L of the total number of transmission streams of n terminal devices participating in MIMO transmission, so that the sum L of the total number of transmission streams of n terminal devices participating in MIMO transmission is less than the sum of the total number of transmission streams of multiple terminal devices. The sum of the number of receiving antennas results in the mismatch of matrix dimensions.

Also, the first channel matrix used by the network device for precoding

Received data received signal

Determine the equivalent channel coefficients. Both the network equipment and the terminal equipment operate and process according to the same receiver assumption to ensure the matching calculated by the sender and receiver. The reporting or downlink notification of the detection weight matrix can be avoided.

Furthermore, the total number of transmission streams in n terminal devices participating in MIMO transmission

Less than the total number of receiving antennas of multiple terminal devices

, if you select L row vectors in the R matrix to form a new matrix

Select L corresponding column vectors in the Q matrix to form a new matrix

Matrix after row/column selection

and

When performing THP precoding, since the number of rows of the B matrix is smaller than the number of receiving antennas, when the B matrix is used for interference cancellation, the inter-user interference and inter-stream interference of the received signals of all antennas cannot be completely eliminated.

If the signal detection is performed only based on the receiving antenna without inter-user interference and inter-stream interference, without detecting the signal of the receiving antenna with inter-user interference and inter-stream interference, this part of the antenna is not used, resulting in power loss; The receiving antenna performs signal detection. Since some receiving antennas have inter-user interference and inter-stream interference, the interference of the received signals of these receiving antennas will be severe, resulting in serious performance leveling.

By adopting the technical solution of the present application, the total number of transmission streams of n terminal devices participating in MIMO transmission

Less than the total number of receiving antennas of multiple terminal devices

When , by reasonably designing the weight matrix V and the receiving weight matrix W, the first channel matrix can be

The number of rows is reduced to be consistent with the total number of transmission streams L of the n terminal devices participating in the MIMO transmission, so that the number of columns of the matrix ^RH can be L.

In this way, the feedback matrix B=GR ^H , and the dimension of the feedback matrix B is also L×L. In this way, the dimension of the channel matrix of the QR decomposition can be reduced, and the computational complexity of the QR decomposition can be reduced.

Moreover, the channel matrix H of the downlink channels of the n terminal devices participating in the MIMO transmission is processed as a first channel matrix with a dimension of L×L

After that, according to the first channel matrix whose dimension is L×L

For interference cancellation, the first channel matrix

It is equivalent to a channel matrix of a virtual downlink channel with the number of receiving antennas L, and the number of receiving antennas of the channel matrix of the virtual downlink channel is

The number of lines L.

In this way, the number of transmission streams L of the n terminal devices can be the same as the number of rows of the channel matrix of the virtual downlink channel, and the interference corresponding to each receiving antenna can be better eliminated in the process of interference cancellation, thereby avoiding the The power loss or residual interference caused by the mismatch between the number of streams and the number of antennas at the receiving end.

The following provides a solution for the terminal equipment to determine and estimate the received weight sub-matrix W' _k .

In step 504, the terminal equipment k can determine the estimated receiving weight sub-matrix W' _k corresponding to the receiving weight sub-matrix W _k corresponding to the terminal equipment according to the received second received signal; , the signal transmission method further includes the steps:

506. The network device sends a second sending signal x ₂ ;

Optionally, the second transmission signal x ₂ is obtained by the network device precoding the second reference signal s ₂ corresponding to the n terminal devices participating in the MIMO transmission according to the weight matrix V,

γ is the power factor.

s ₂ includes second reference signals corresponding to n terminal devices.

is the second reference signal corresponding to terminal device k.

Indicates the second reference signal symbol corresponding to the lth port of the kth terminal device. Each second reference signal port corresponds to one spatial layer. The second reference signals corresponding to different ports may be quadrature signals. The second reference signal symbols corresponding to different ports may be multiplexed by one or more of time division multiplexing, frequency division multiplexing and code division multiplexing.

The network device may transmit multiple second transmit signals, or may transmit multiple second transmit signal symbols. The multiple second transmission signals may occupy different time-frequency resources. The second transmission signal x ₂ corresponding to the n terminal devices includes the second reference signal symbols corresponding to the L _k ports,

Indicates the second reference signal symbol corresponding to the lth port of the terminal device k. The second reference signals of different ports may be quadrature signals. If the different ports of the second reference signal s ₂ are orthogonal, the second transmission signal corresponding to the terminal device k

507. The terminal device k receives the second received signal corresponding to the terminal device k

the second received signal

is the received signal received by the receiving end after the second transmitted signal x ₂ passes through the downlink channel corresponding to the terminal device k. y ₂ =Hx ₂ +n. in

Optionally, the different ports of the second reference signal s ₂ are orthogonal, and the second received signal corresponding to the terminal device k can be expressed as

in,

is additive white Gaussian noise, and or interference.

In this way, the terminal device k can receive the second received signal according to the

Determine the estimated receiving weight sub-matrix W' k corresponding to the receiving weight sub-matrix W _k corresponding to the terminal device _k .

Step 504 may include:

5041. Terminal device k receives the signal according to the second

Perform channel estimation to obtain the second channel estimation matrix corresponding to terminal equipment k

specifically,

reference signal

For the receiving end, it can be known that the terminal equipment k at the receiving end can obtain an estimate of the equivalent channel, and the equivalent channel

The dimension of is N _R ×L _k ,

is based on the second received signal

and the second reference signal

Estimated result of H _k V _k . Δ ₁ is the estimation error matrix corresponding to the channel estimation.

For example, the terminal device k may use a least squares (Least Square, LS) channel estimation algorithm or a Minimum Mean Squared Error (Minimum Mean Squared Error, MMSE) channel estimation algorithm, etc. to perform channel estimation.

5042. The terminal device k estimates the matrix according to the second channel

and receiver type, determine the estimated receiving weight sub-matrix W' _k corresponding to the receiving weight sub-matrix W _k .

It can be understood that the estimated receiving weight sub-matrix W′ _k obtained by the terminal device k is an estimated value of the receiving weight sub-matrix W _k corresponding to the terminal device k.

The receiving weight sub-matrix W _k corresponding to the terminal equipment k is related to the channel matrix H _k corresponding to the terminal equipment k and the corresponding weight matrix V _k . The receiver type is the receiver type sent by the terminal device k to the network device. The network device determines the receiving weight sub-matrix W k corresponding to the terminal device k according to the receiver type sent by the terminal device k and the downlink channel H _k corresponding to the terminal device _k . In this way, the terminal device k can more accurately determine the estimated reception weight sub-matrix W' _k corresponding to the reception weight sub-matrix W _k according to the receiver type sent to the network device.

Specifically, the terminal device k calculates the estimated receiving weight sub-matrix corresponding to the terminal device k according to the receiver type sent to the network device

in,

means based on

deal with it accordingly. The corresponding processing can be a linear processing method or a nonlinear processing method.

For example, if the receiver type sent by the terminal device k to the network device is an MRC receiver,

If the type of receiver sent by the terminal equipment is an MMSE receiver, W _k =[(H _k V _k ) ^H (H _k V _k )+σ ² I] ^-1 (H _k V _k ) ^H . where I is the identity matrix. σ ² is an adjustment factor, which is related to the transmitted signal power and/or noise power.

In this way, the terminal device k according to the receiver type and the second received signal corresponding to the second reference signal

Determine the estimated receiving weight sub-matrix W' k corresponding to the terminal equipment _k . In this application, when performing channel estimation, in addition to the reference signal used for direct channel estimation, another reference signal (second reference signal) is also sent. This scheme of implicitly indicating the receiving weight sub-matrix through the second reference signal can avoid the signaling notification of the receiving weight matrix, reduce the downlink signaling overhead, and avoid the quantization during notification. performance loss.

In this embodiment of the present application, the first reference signal and the second reference signal may be demodulation reference signals (DMRS). The DMRS resource 1 corresponding to the first reference signal and the DMRS resource 2 corresponding to the second reference signal may occupy different time and frequency resources.

As shown in the schematic diagram of the scenario shown in FIG. 5C , the horizontal axis represents OFDM symbols, and the vertical axis represents frequency domain subcarriers. Each cell represents a resource particle. For example, DMRS resource 1 and DMRS resource 2 may be arranged in a time division manner. Among them, DMRS resource 1 occupies 12 subcarriers of the third OFDM symbol in a resource block (resource block, RB), and DMRS resource 2 occupies 12 subcarriers of the ninth OFDM symbol in one RB.

Of course, in other embodiments, the DMRS resource 1 and the DMRS resource 2 are not limited to be arranged according to the example in FIG. 5C , nor are they limited to be arranged in a time-division manner. DMRS resource 1 and DMRS resource 2 may have different time-frequency resource mapping methods.

In other embodiments, the first reference signal and the second reference signal may also be other types of reference signals. For example, it can be a channel state information-reference signal (channel state information reference signal, CSI-RS), a cell reference signal (cell information reference signal, CRS), a phase tracking reference signal (phase tracking reference signal, PTRS) and the like.

The first reference signal and the second reference signal may be different types of reference signals. For example, the first reference signal is a DMRS, and the second reference signal may be a CSI-RS.

It should be understood that the above-mentioned solution for the terminal device to determine and estimate the receiving weight sub-matrix _W'k according to the second transmission signal is for illustration purposes, and the present application does not limit the terminal device to only use the solutions of the above steps 505, 506 and 504 to determine the estimate Receive weight submatrix W' _k . In other embodiments, the terminal device k may also determine the estimated reception weight sub-matrix W′ _k corresponding to the reception weight sub-matrix W _k corresponding to the terminal device according to a manner agreed with the network device.

The following describes the transmission scheme of the data signal in the scenario where the dimensionality reduction matrix includes the receiving weight matrix W and the weight matrix V. Specifically, as shown in the schematic flow chart shown in FIG. 6 , the transmission method of the data signal includes:

601. The network device according to the first channel matrix

Precoding the transmission data signal s to obtain the precoded transmission data signal c;

The transmission data signal s=(s ₁ , s ₂ , . . . , s _n ) ^T . The transmitted data signal s may also be understood as a transmitted symbol vector corresponding to n terminal devices participating in MIMO transmission, or a multi-user transmitted symbol vector.

_sk can be expressed as

_sk is a transmitted symbol vector corresponding to terminal equipment k, or _sk is a transmitted data signal corresponding to terminal equipment k. s _k,l (l∈[1,L _k ]) represents the data symbol sent by the lth transport stream corresponding to terminal device k.

Specifically, the network device is based on the first channel matrix

THP precoding is performed on the transmission data signal to obtain a precoded transmission data signal c. The THP precoding includes a process of nonlinear precoding and a process of linear precoding.

In the process of nonlinear precoding, the network device performs a stream-by-stream serial interference cancellation operation based on the feedback matrix B. B=GR ^H . The R matrix is passed to the first channel matrix

QR decomposition of the conjugate transposed matrix of , we get:

For example, the first channel matrix

The dimension of is L×L;

where r _kk , represents the element corresponding to the k-th row and the k-th column of the R matrix. Therefore, matrix B is a lower triangular matrix with elements on the main diagonal of 1. The matrix Q is a unitary matrix of dimension L×L.

n terminal devices participate in MIMO transmission, and each terminal device corresponds to a transmitted symbol vector

where L _k represents the number of transport streams sent by terminal device k. _sk,l (l∈[1, _Lk ]) denotes the symbol sent by the lth transport stream of terminal device k.

In the process of nonlinear precoding, the network device performs interference cancellation on the multi-user transmitted symbol _vector s=(s ₁ , s ₂ , ^. A modulo operation is also performed after the interference cancellation operation. After the modulo operation, the network device obtains the transmitted symbol vector x=(x ₁ , x ₂ , . . . , x _n ) ^T . The total number of transmission streams sent by n terminal devices is

Rearrange the index of each element in the multi-user transmitted symbol vector s, denoted as s=(s ₁ , s ₂ , . . . , s _L ) ^T . Similarly, each element in the transmitted symbol vector x is rearranged and denoted as x=(x ₁ ,x ₂ ,...,x _L ) ^T .

For transport stream i corresponding to spatial layer i, the transmitted symbols output by the nonlinear precoding step

B _i,l represents the element corresponding to the i-th row and the l-th column of the B matrix. Mod _τ {x} represents the modulo operation, for a given modulo operation parameter τ,

d _k represents the rounded part obtained by the modulo operation. The network device obtains the transmitted symbol vector x=B ^-1 v through the above non-linear operation.

Among them, v=(v ₁ , v ₂ ,...,v _L ) ^T , which represents the transmitted data symbol vector after signal perturbation (modulo operation) obtained by n users after THP nonlinear operation, which can be recorded as

in

Represents the transmitted data symbol vector corresponding to terminal equipment k after signal disturbance.

In the process of linear precoding, the network device precodes the transmitted symbol vector x according to the matrix Q and the weight matrix V, and obtains the transmitted data signal c corresponding to the n terminal devices participating in the MIMO transmission. Specifically, sending a data signal

where β is the power normalization factor.

The process that the network device performs precoding according to the matrix Q and the weight matrix V can be understood as a process of linear processing.

602. The network device sends the precoded sending data signal c;

603. The terminal device k receives the first received data signal

It can be understood that the received data signals of n terminal devices participating in MIMO transmission

Among them, the first received data signal

is the received data signal corresponding to the terminal device k among the n terminal devices.

604. The terminal device k detects the first received data signal according to the equivalent channel coefficient corresponding to the terminal device k and the receiving weight sub-matrix W' _k

Specifically, the terminal equipment k uses the receiving weight sub-matrix W' _k corresponding to the terminal equipment k, and the left multiplication of the received data signal is

get the second received data signal

It can be understood that the second received data signals of the n terminal devices participating in the MIMO transmission

where n represents the corresponding additive noise and or interference.

The matrix G ^-1 is a diagonal matrix, and the main diagonal element corresponding to the ith row and the ith column of the matrix G is the reciprocal of the main diagonal element corresponding to the ith row and the ith column of the ^RH matrix or R matrix.

where r _kk represents the element corresponding to the k-th row and the k-th column of the R ^H matrix, we can get

The second received data signal corresponding to terminal device k can be expressed as

Represents the symbol vector sent after modulo operation corresponding to terminal device k.

understandably,

In the matrix, m main diagonal elements corresponding to terminal equipment k are equivalent channel coefficients corresponding to m transport streams of terminal equipment k. The terminal device may use the equivalent channel coefficient obtained in the above step 505 to detect the received data signal to obtain an estimation result of the transmitted data signal. For example, the terminal device may use the equivalent channel coefficient obtained in the above step 505 to equalize the received data signal, and then perform a modulo operation to obtain an estimate of the transmitted data signal.

2. The dimensionality reduction matrix includes the receiving weight matrix W.

In some possible implementations, the first channel matrix

second channel matrix

Among them, the number of rows of the receiving weight matrix W is less than or equal to the sum of the number of receiving antennas of the n terminal devices participating in the MIMO transmission, that is, the first channel matrix

In some other possible implementations, the first channel matrix

second channel matrix

Among them, the number of columns of the receiving weight matrix W is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission, that is, a channel matrix

k=1,2,...,n, the dimension is

The kth sub-matrix corresponding to the main diagonal of the receiving weight matrix W is the receiving weight sub-matrix W k corresponding to the terminal device _k . The receiving weight sub-matrix W _k corresponding to the terminal equipment k is determined by the network equipment according to the receiver type of the terminal equipment k.

The following is the first channel matrix

As an example, the technical solution of the signal transmission method of the present application is described in the scenario where the dimensionality reduction matrix includes the receiving weight matrix W. Specifically, as shown in the schematic flowchart in FIG. 7 , the signal transmission method includes the following steps:

701. The network device precodes the first reference signal s ₁ according to the matrix Q to obtain the first transmitted signal x ₁ ;

The Q matrix is the network device based on the first channel matrix

obtained by QR decomposition,

The Q matrix is a unitary matrix. The R matrix is an upper triangular matrix.

first channel matrix

For example, the first channel matrix

The number of lines of can be the sum L of the number of transport streams of multiple terminal devices, the dimension of R is L×L, and the dimension of Q is N _T ×L. In this way, the reduced dimension matrix R is a square matrix, which avoids the problem of mismatching matrix dimensions when the number of transmission streams L is less than the total number of receiving antennas, and can flexibly adapt to various antenna configurations and transmission scenarios.

In one possible implementation,

α is the power control factor. The network device precodes the first reference signals s ₁ corresponding to the n terminal devices participating in the MIMO transmission according to the matrix Q, and obtains the first transmission signal x ₁ corresponding to the n terminal devices.

The first reference signal corresponding to the terminal device k

Contains the first reference signal symbols corresponding to the L _k ports,

Indicates the first reference signal symbol corresponding to the lth port of the kth terminal device. The first reference signals of different ports may be quadrature signals. The terminal device k is any one of the n terminal devices participating in the MIMO transmission.

In another possible implementation,

Among them, the matrix B can be expressed as B=GR ^H , the G matrix is a diagonal matrix with dimension L×L, and its main diagonal elements are the reciprocals of the main diagonal elements of the R matrix, that is,

The dimension of matrix B is L×L. α is the power control factor. The network device precodes the first reference signals s ₁ corresponding to the n terminal devices participating in the MIMO transmission according to the matrix Q and the matrix B, and obtains the first transmission signal x ₁ corresponding to the n terminal devices.

The first reference signal corresponding to the terminal device k

Contains the first reference signal symbols corresponding to the L _k ports,

702. The network device sends a first sending signal x ₁ .

703. The terminal device k receives the first received signal

In the implementation manner of , the vector received by n terminal devices participating in MIMO transmission can be expressed as

where n is additive white Gaussian noise and or interference. in,

second channel matrix

The R matrix and the Q matrix are the network equipment to the first channel matrix

obtained by QR decomposition,

For convenience, define

Then the first received signal corresponding to the kth terminal device

n _k is additive white Gaussian noise, sum or interference.

in the above

where n is additive white Gaussian noise. in,

second channel matrix

obtained by QR decomposition,

For convenience, define

Then the first received signal corresponding to the kth terminal device

n _k is additive white Gaussian noise and or interference.

704. The terminal equipment k determines the estimated receiving weight sub-matrix W' k corresponding to the receiving weight sub-matrix W _k corresponding to the terminal equipment _k ;

For example, the terminal device k can also determine the receiving weight sub-matrix W _k according to the second received signal corresponding to the second sending signal sent by the network device; or, the terminal device k can determine the receiving weight sub-matrix W _k in a manner agreed with the network device The corresponding estimated receive weight submatrix W' _k . The estimated receiving weight sub-matrix W' _k can be understood as an estimated matrix of the receiving weight sub-matrix W _k .

It can be understood that step 704 may be performed after step 703 or may be performed before step 703 .

705. The terminal device k estimates the first received signal corresponding to the terminal device k according to the received weight sub-matrix W' _k

Obtain the third received signal corresponding to the first received signal

Terminal device k receives the signal according to the third

The first reference signal corresponding to terminal equipment k

For example, based on the above

The corresponding third received signals of terminal equipment 1-terminal equipment n:

Based on the relevant description of the relationship between the receiving weight matrix W and the estimated receiving weight matrix W' in the scenario where the above-mentioned dimensionality reduction matrix includes the receiving weight matrix W, in an ideal case, assuming that W'=W, the above formula can be expressed as

When there is a channel estimation error,

first reference signal

The network equipment and terminal equipment k on both sides of the transceiver are known, so the equivalent channel matrix can be obtained

's estimate. In an implementation manner, if the first reference signal corresponding to each terminal device is an orthogonal signal, the third received signal corresponding to terminal device k

It can be expressed as

in

express

A sub-matrix consisting of elements corresponding to the row and column corresponding to terminal device k. The terminal device k can receive the signal through the third corresponding to the terminal device k

Based on the first reference signal

Perform channel estimation to get the estimation result

In this way, the network device uses the first channel matrix for precoding

is obtained according to the receiving weight sub-matrix W _k , and the terminal device multiplies the first received signal by left-multiplying the estimated receiving weight matrix W'

Received data received signal

^RH or

is the lower triangular matrix, and the R matrix is the first channel matrix

It is obtained by QR decomposition.

The elements on the main diagonal in each row correspond to the equivalent channel coefficients of a transport stream. The equivalent channel coefficients can be used to detect data transmitted by the transport stream.

For another example, based on the above

Estimating the receiving weight matrix

The estimated receiving weight matrix W' can be understood as an estimated matrix of the receiving weight matrix W. The estimated receiving weight matrix W' can be equivalent to the receiving weight matrix W superimposed on the channel estimation error matrix, that is, W'=W+ _ΔW . The estimated receiving weight matrix W' is a block diagonal matrix, and W' includes estimated receiving weight sub-matrices W' ₁ , W' ₂ corresponding to W ₁ , W ₂ , ..., W _n included in the receiving weight matrix W, respectively, ..., _W'n .

In an ideal case, assuming W′=W, the above formula can be expressed as

When there is a channel estimation error,

obtained by QR decomposition,

The data receiving signal corresponding to the terminal equipment k

or

in,

is the submatrix corresponding to the kth terminal device in matrix G ^-1 ,

in,

is a matrix

The submatrix corresponding to the kth terminal device in ,

Due to the first reference signal

The network equipment and terminal equipment on both sides of the transceiver are known, so the equivalent channel matrix can be obtained

's estimate.

In this way, the network device uses the first channel matrix for precoding

Received data received signal

The number of rows and/or columns is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission. By designing the receiving weight matrix W reasonably, the first channel matrix can be

The number of rows is the sum L of the total number of transmission streams of n terminal devices participating in MIMO transmission, and the solution is that the sum of the total number of transmission streams L of n terminal devices participating in MIMO transmission is less than the sum of the total number of receiving antennas of multiple terminal devices and, resulting in a mismatch of matrix dimensions.

In step 704, the terminal device k may determine the estimated reception weight sub-matrix _W'k corresponding to the reception weight sub-matrix _Wk corresponding to the terminal device according to the received second received signal; before step 704, the signal transmission method further includes the steps:

706. The network device sends a second sending signal x ₂ .

Optionally, the second transmission signal may be understood as the second reference signal corresponding to the n terminal devices,

γ is the power factor, and the value of γ can be 1.

in,

s ₂ includes second reference signals corresponding to n terminal devices.

is the second reference signal corresponding to terminal device k. The second transmission signal corresponding to the terminal device k

For the explanation of x ₂ , reference may be made to the relevant description in the signal transmission scheme in the scenario where the dimensionality reduction matrix includes the receiving weight matrix W and the weight matrix V, and the description will not be repeated here.

707. The terminal device k receives the second received signal corresponding to the terminal device k

the second received signal

is the received signal received by the receiving end after the second transmitted signal x ₂ passes through the downlink channel corresponding to the terminal device k. y ₂ =Hx ₂ +n. If the different ports of the second reference signal s ₂ are orthogonal, the second received signal corresponding to the terminal device k can be expressed as

in,

is additive white Gaussian noise, and or interference.

Step 704 may include:

7041. Terminal device k receives the signal according to the second

specifically,

Due to the reference signal

For the receiving end, it can be known that the terminal equipment k at the receiving end can obtain the estimation of the equivalent channel

in,

The dimension is

is based on the second received signal

and the second reference signal

Estimated result of _Hk . Δ ₁ is the estimation error matrix corresponding to the channel estimation.

For example, the terminal device k may perform channel estimation using the LS channel estimation algorithm or the MMSE channel estimation algorithm, or the like.

7042. The terminal device k estimates the matrix according to the second channel

For the specific implementation scheme of step 7042, please refer to the relevant description of step 5042 in the foregoing embodiment, and the description will not be repeated here.

The first reference signal and the second reference signal may be demodulation reference signals (DMRS). The DMRS resource 1 corresponding to the first reference signal and the DMRS resource 2 corresponding to the second reference signal may occupy different time and frequency resources.

It should be understood that the above solution of determining and estimating the receiving weight sub-matrix _W'k by the terminal device according to the second transmission signal is for illustration, and the present application does not limit that the terminal device can only use the solutions of the above steps 705, 706 and 704 to determine the estimate Receive weight submatrix W' _k . In other embodiments, the terminal device k may also determine the estimated reception weight sub-matrix W′ _k corresponding to the reception weight sub-matrix W _k corresponding to the terminal device according to a manner agreed with the network device.

The following describes the transmission scheme of the data signal in the scenario where the dimensionality reduction matrix includes the receiving weight matrix W. Specifically, the transmission method of the data signal includes:

711. The network device is based on the first channel matrix

first channel matrix

is the transmitted symbol vector corresponding to terminal device k.

Specifically, the network device is based on the first channel matrix

For the process of nonlinear precoding, reference may be made to the relevant description in the signal transmission scheme in the scenario where the dimension reduction matrix includes the receiving weight matrix W and the weight matrix V, and the description is not repeated here.

In the process of linear precoding, for n terminal devices participating in MIMO transmission, the network device precodes the transmitted symbol vector according to the matrix Q to obtain the transmitted data signal c corresponding to the n terminal devices. Specifically, sending a data signal

where β is the power normalization factor.

The process that the network device performs precoding according to the matrix Q can be understood as a process of linear processing.

712. The network device sends the precoded sending data signal c;

713. Terminal device k receives the first received data signal

Among them, the first received data signal

is the received data signal corresponding to the terminal device k.

714. The terminal device k detects the first received data signal according to the equivalent channel coefficient corresponding to the terminal device k and the receiving weight sub-matrix W' _k

get the second received data signal

where n represents the corresponding additive noise and or interference.

The matrix G ^-1 is a diagonal matrix, and the main diagonal element corresponding to the i-th row and the i-th column is the reciprocal of the main diagonal element corresponding to the i-th row and the i-th column of the ^RH matrix. The second received data signal corresponding to terminal device k can be expressed as

understandably,

In the matrix, m main diagonal elements corresponding to terminal equipment k are equivalent channel coefficients corresponding to m transport streams of terminal equipment k. The terminal device may use the equivalent channel coefficient obtained in the above step 705 to detect the received data signal to obtain an estimation result of the transmitted data signal.

Among them, based on the above

In the implementation manner of , an equivalent channel matrix ^RH is obtained based on the first received signal, wherein the elements located on the main diagonal in each row of ^RH correspond to the equivalent channel coefficients of one transmission stream. The u-th spatial layer of terminal equipment k, the equivalent channel coefficient obtained based on the first received signal is

is a matrix

Elements located on the main diagonal in the row corresponding to the u-th spatial layer of terminal device k. based on

The sum-modulo operation can estimate the data signal corresponding to the u-th spatial layer of the terminal device k. Based on the above

The implementation method of , obtains the equivalent channel matrix based on the first received signal

based on equivalent channel matrix

The sum-modulo operation can estimate the corresponding data signal sent by the terminal device k.

An embodiment of the present application further provides a signal transmission device. As shown in FIG. 8 , a schematic structural diagram of the signal transmission device is shown. The signal transmission device 800 includes a receiving unit 801 and a processing unit 802; the signal transmission device may be, for example, a terminal device, or the The signal transmission apparatus is deployed in the terminal equipment; the receiving unit 801 is used for receiving the first received signal; the first received signal is sent to the terminal equipment through the downlink channel corresponding to the terminal equipment after precoding the first reference signal according to the first channel matrix The first channel matrix is obtained according to the second channel matrix. The number of rows and/or columns of the first channel matrix is less than or equal to the sum of the number of receiving antennas of one or more terminal devices participating in MIMO transmission. The channel matrix is a channel matrix of downlink channels corresponding to one or more terminal devices; the processing unit 802 is configured to obtain equivalent channel coefficients corresponding to the terminal devices according to the first received signal.

In the technical solutions of the embodiments of the present application, the first received signal is sent to the terminal device through the downlink channel corresponding to the terminal device after precoding the first reference signal according to the first channel matrix, and the first channel matrix is based on the second channel matrix. The number of rows and/or columns of the first channel matrix obtained from the matrix is less than or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission, so that the difficulty of matrix calculation can be reduced in the process of THP precoding, It makes the calculation of THP precoding simpler.

In some embodiments, the first channel matrix

W is the reception weight matrix, V is the weight matrix, and H is the second channel matrix. The number of rows of the reception weight matrix and/or the number of columns of the weight matrix is less than or equal to the reception of one or more terminal devices participating in MIMO transmission. Sum of the number of antennas.

Optionally, the number of rows of the receiving weight matrix is the sum of the numbers of transport streams of one or more terminal devices, and/or the number of columns of the weight matrix is the sum of the numbers of transport streams of multiple terminal devices.

In some possible implementations, the receiving weight matrix includes a receiving weight sub-matrix corresponding to the terminal device; the receiving unit 801 is further configured to receive the second received signal;

The processing unit 802 is also used to:

Optionally, the weight matrix includes a weight sub-matrix corresponding to the terminal device, and the second received signal is sent to the terminal device through a downlink channel corresponding to the terminal device after the network device precodes the second reference signal according to the weight sub-matrix. of.

In some embodiments, the first channel matrix

W is the receiving weight matrix, and the number of rows in the receiving weight matrix is less than the sum of the number of receiving antennas of one or more terminal devices participating in the MIMO transmission.

Optionally, the number of rows of the receiving weight matrix is the sum of the numbers of transport streams of multiple terminal devices.

The processing unit 802 is also used to:

In some embodiments, the receiving unit 801 is further configured to receive a first received data signal, where the first received data signal is sent by the network device through the downlink channel corresponding to the terminal device after precoding the transmitted data signal according to the first channel matrix. To the terminal equipment; the processing unit 802 is further configured to detect the first received data signal according to the estimated receiving weight sub-matrix and the equivalent channel coefficient corresponding to the terminal equipment.

In some embodiments, the processing unit 802 is specifically configured to:

The first received data signal is left-multiplied by the estimated receiving weight sub-matrix to obtain the second received data signal corresponding to the first received data signal;

According to the second received data signal and the equivalent channel coefficient corresponding to the terminal device, the estimation result of the transmitted data signal is obtained.

Optionally, the signal transmission apparatus 800 further includes a sending unit configured to send the receiver type of the terminal device, and the receiver type of the terminal device is used for the network device to determine the receiving right matrix.

It should be understood that the technical effects and related supplementary descriptions of the various embodiments of the signal transmission method described above are also applicable to the signal transmission apparatus 800 in this embodiment of the present application, and the description will not be repeated here.

An embodiment of the present application further provides a signal transmission device for MIMO transmission. As shown in FIG. 9, a schematic structural diagram of the signal transmission device is shown. The signal transmission device 900 includes a processing unit 901 and a sending unit 902; the signal transmission The apparatus 900 may be, for example, network equipment, or the signal transmission apparatus may be deployed in the network equipment; wherein, the processing unit 901 is configured to precode the first reference signal according to the first channel matrix to obtain the first transmitted signal, and the first channel matrix is Obtained according to the second channel matrix, the number of rows and/or columns of the first channel matrix is less than or equal to the sum of the number of receiving antennas of one or more terminal devices participating in MIMO transmission, and the second channel matrix is one or more The channel matrix of the downlink channel of the terminal device; the sending unit 902 is configured to send the first sending signal.

In the technical solution of the present application, the signal transmission device precodes the first reference signal according to the first channel matrix, the first channel matrix is obtained according to the second channel matrix, and the number of rows and/or columns of the first channel matrix is less than Or equal to the sum of the number of receiving antennas of n terminal devices participating in MIMO transmission, so that the difficulty of matrix calculation can be reduced in the process of THP precoding, and the calculation of THP precoding can be made simpler.

In some embodiments, the first channel matrix

W is a receiving weight matrix, V is a weight matrix, and the number of rows of the receiving weight matrix and/or the number of columns of the weight matrix is less than or equal to the sum of the number of receiving antennas of one or more terminal devices.

Optionally, the number of rows of the receiving weight matrix is the sum of the number of transport streams of one or more terminal devices, and/or the number of columns of the weight matrix is the number of transport streams of one or more terminal devices.

Optionally, the weight matrix includes a weight sub-matrix corresponding to each terminal device in one or more terminal devices, and the weight sub-matrix corresponding to each terminal device is determined according to the channel matrix of the downlink channel corresponding to the terminal device. of.

In a possible implementation manner, the sending unit 902 is further configured to send a second sending signal, and each terminal device in the one or more terminal devices of the second sending signal determines the estimated reception value corresponding to its corresponding reception weight sub-matrix weight matrix.

Optionally, the second transmission signal is obtained by precoding the second reference signal by the network device according to the weight sub-matrix.

In some embodiments, the first channel matrix

W is the receiving weight matrix, and the number of rows in the receiving weight matrix is less than or equal to the sum of the number of receiving antennas of one or more terminal devices.

Optionally, the received weight matrix includes a receiving weight sub-matrix corresponding to each terminal device in the plurality of terminal devices, and the receiving weight sub-matrix corresponding to each terminal device is determined by the network device according to the receiver type of the terminal device.

Optionally, the processing unit 901 is further configured to precode the transmission data signal according to the first channel matrix to obtain the precoded transmission data signal; the transmission unit is further configured to send the precoded transmission data signal.

It should be understood that the technical effects and related supplementary descriptions of the various embodiments of the signal transmission method described above are also applicable to the signal transmission apparatus 900 in this embodiment of the present application, and the description is not repeated here.

The present application provides a computer program product, the computer program product includes: a computer program (also referred to as code, or instruction), when the computer program is run, the computer executes any of the above method embodiments that can be executed by a network device. steps or perform steps that can be performed by a terminal device in any of the foregoing method embodiments.

The present application provides a computer-readable storage medium, where the computer-readable medium stores a computer program (also referred to as code, or instruction) when it runs on a computer, so that the computer can execute any of the above method embodiments and can be accessed by a network The steps performed by the device or the steps performed by the terminal device in any of the foregoing method embodiments are performed.

It should also be understood that the first, second, third, fourth and various numeral numbers mentioned herein are only for the convenience of description, and are not used to limit the scope of the present application.

It should be understood that the term "and/or" in this document is only an association relationship to describe associated objects, indicating that there can be three kinds of relationships, for example, A and/or B, which can mean that A exists alone, and A and B exist at the same time , there are three cases of B alone. In addition, the character "/" in this document generally indicates that the related objects are an "or" relationship.

It should be understood that, in various embodiments of the present application, the size of the sequence numbers of the above-mentioned processes does not mean the sequence of execution, and the execution sequence of each process should be determined by its functions and internal logic, and should not be dealt with in the embodiments of the present application. implementation constitutes any limitation.

Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may implement the described functionality using different methods for each particular application, but such implementations should not be considered beyond the scope of this application.

Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the above-described systems, devices and units may refer to the corresponding processes in the foregoing method embodiments, which will not be repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed system, apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not implemented. On the other hand, the shown or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of devices or units, and may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit.

The functions, if implemented in the form of software functional units and sold or used as independent products, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be embodied in the form of a software product in essence, or the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including Several instructions are used to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), magnetic disk or optical disk and other media that can store program codes .

The steps in the method of the embodiment of the present application may be adjusted, combined and deleted in sequence according to actual needs.

The modules in the apparatus of the embodiment of the present application may be combined, divided and deleted according to actual needs.

As mentioned above, the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand: The technical solutions described in the embodiments are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

A signal transmission method for multiple-input multiple-output MIMO transmission, comprising:

The terminal equipment receives the first received signal; the first received signal is sent to the terminal equipment through the downlink channel corresponding to the terminal equipment after precoding the first reference signal according to the first channel matrix, and the first received signal is sent to the terminal equipment through the downlink channel corresponding to the terminal equipment. A channel matrix is obtained according to the second channel matrix. The number of rows and/or columns of the first channel matrix is less than or equal to the sum of the number of receiving antennas of one or more terminal devices participating in MIMO transmission. The second channel matrix is the channel matrix of the downlink channel corresponding to the one or more terminal devices;

The terminal device obtains the equivalent channel coefficient corresponding to the terminal device according to the first received signal.
The method of claim 1, wherein the first channel matrix
W is the reception weight matrix, V is the weight matrix, and H is the second channel matrix. The number of rows of the reception weight matrix and/or the number of columns of the weight matrix is less than or equal to the number of the participating MIMO transmission. The sum of the number of receive antennas of one or more terminal devices.
The method according to claim 2, wherein the number of rows of the reception weight matrix is the sum of the number of transport streams of the one or more terminal devices, and/or the number of columns of the weight matrix is The sum of the number of transport streams of the plurality of terminal devices.
The method according to claim 2 or 3, wherein the receiving weight matrix comprises a receiving weight sub-matrix corresponding to the terminal device;

The method also includes:

the terminal device receives the second received signal;

Obtaining, by the terminal device, according to the first received signal, the equivalent channel coefficient corresponding to the terminal device includes:

determining, by the terminal device, an estimated receiving weight sub-matrix corresponding to the receiving weight sub-matrix according to the second received signal;

The terminal device obtains an equivalent channel coefficient corresponding to the terminal device according to the estimated reception weight sub-matrix and the first received signal.
The method according to claim 4, wherein the weight matrix includes a weight sub-matrix corresponding to the terminal device, and the second received signal is a second reference of the network device according to the weight sub-matrix. After the signal is precoded, it is sent to the terminal device through the downlink channel corresponding to the terminal device.
The method of claim 1, the first channel matrix
W is a receiving weight matrix, and the number of rows of the receiving weight matrix is less than the sum of the number of receiving antennas of the one or more terminal devices participating in the MIMO transmission.
The method according to claim 6, wherein the number of rows of the reception weight matrix is the sum of the number of transport streams of the plurality of terminal devices.
The method according to claim 6 or 7, wherein the receiving weight matrix comprises a receiving weight sub-matrix corresponding to the terminal device;

The method also includes:

the terminal device receives the second received signal;

Obtaining, by the terminal device, according to the first received signal, the equivalent channel coefficient corresponding to the terminal device includes:

determining, by the terminal device, an estimated receiving weight sub-matrix corresponding to the receiving weight sub-matrix according to the second received signal;

The terminal device obtains an equivalent channel coefficient corresponding to the terminal device according to the estimated reception weight sub-matrix and the first received signal.
The method according to any one of claims 4, 5 and 8, wherein the method further comprises:

The terminal device receives a first received data signal, and the first received data signal is sent to the terminal equipment;

The terminal device detects the first received data signal according to the estimated reception weight sub-matrix and equivalent channel coefficients corresponding to the terminal device.
The method according to claim 9, wherein the terminal device detecting the data signal according to the estimated receiving weight sub-matrix and the equivalent channel coefficient corresponding to the terminal device comprises:

The terminal device left-multiplies the first received data signal by using the estimated receiving weight sub-matrix to obtain a second received data signal corresponding to the first received data signal;

The terminal device obtains an estimation result of the transmitted data signal according to the second received data signal and an equivalent channel coefficient corresponding to the terminal device.
The method according to any one of claims 2-10, wherein the method further comprises:

The terminal device sends the receiver type of the terminal device, and the receiver type of the terminal device is used by the network device to determine the reception weight matrix.
A signal transmission method for multiple-input multiple-output MIMO transmission, comprising:

The network device precodes the first reference signal according to the first channel matrix to obtain the first transmitted signal, the first channel matrix is obtained according to the second channel matrix, and the number of rows and/or columns of the first channel matrix , which is less than or equal to the sum of the number of receiving antennas of one or more terminal devices participating in MIMO transmission, and the second channel matrix is the channel matrix of the downlink channel of the one or more terminal devices;

The network device transmits the first transmit signal.
The method of claim 12, wherein the first channel matrix
W is a receiving weight matrix, V is a weight matrix, and the number of rows of the receiving weight matrix and/or the number of columns of the weight matrix is less than or equal to the sum of the number of receiving antennas of the one or more terminal devices.
The method according to claim 13, wherein the number of rows of the reception weight matrix is the sum of the number of transport streams of the one or more terminal devices, and/or the number of columns of the weight matrix is the Specifies the number of transport streams for one or more terminal devices.
The method according to claim 13 or 14, wherein the weight matrix comprises a weight sub-matrix corresponding to each terminal device in the one or more terminal devices, and the weight corresponding to each terminal device The sub-matrix is determined according to the channel matrix of the downlink channel corresponding to the terminal device.
The method of claim 15, wherein the method further comprises:

The network device sends a second transmission signal, and in the second transmission signal, each terminal device in the one or more terminal devices determines an estimated reception weight sub-matrix corresponding to its own corresponding reception weight sub-matrix.
The method according to claim 16, wherein the second transmission signal is obtained by precoding the second reference signal by the network device according to the weight sub-matrix.
The method of claim 12, wherein the first channel matrix
W is a receiving weight matrix, and the number of rows of the receiving weight matrix is less than or equal to the sum of the number of receiving antennas of the one or more terminal devices.
The method according to any one of claims 13-18, wherein the reception weight matrix comprises a reception weight sub-matrix corresponding to each terminal device in the plurality of terminal devices, and the reception weight corresponding to each terminal device The weight sub-matrix is determined by the network device according to the receiver type of the terminal device.
The method according to any one of claims 12-19, wherein the method further comprises:

The network device performs precoding on the transmission data signal according to the first channel matrix to obtain the precoded transmission data signal;

The network device sends the precoded transmission data signal.
A communication device, characterized in that it includes a processor and a memory, wherein the memory is used to store computer instructions, and the processor executes the computer instructions, so that the communication device executes any one of claims 1-11. method, or causing the communication device to perform the method of any one of claims 12-20.
A computer-readable storage medium, characterized in that the computer-readable storage medium stores computer instructions, the computer instructions instructing a communication device to execute the method or claim in any one of claims 1-11 The method of any one of 12-20.
A chip, characterized in that it includes: a processor and an interface for executing computer programs or instructions stored in a memory, and executing the method described in any one of claims 1-11 or any one of claims 12-20 the method described.
A computer program product, characterized in that the computer program product comprises a computer program, which, when the computer program is run on a computer, causes the computer to execute the method or the rights described in any one of claims 1-11 The method of any of claims 12-20.