CN111835390B - Channel measurement method, communication device and computer readable medium - Google Patents

Abstract

The present application provides a channel measurement method and a communication device. The method includes: a network device determines a target precoding vector for data transmission based on feedback information received K times; precoding the data according to the target precoding vector, and sending the precoded data. The feedback information received in the K times is determined based on the precoding reference signals sent in the K times, and the feedback information received in the kth time is used to indicate the weight of the N _k precoding vectors, and the weighted sum of the N _k precoding vectors is One of the N _k+1 precoding vectors; the N _k precoding vectors are the precoding vectors used to generate the precoding reference signal transmitted at the kth time, and the _Nk+1 precoding vectors are used to generate the kth precoding reference signal. The precoding vector of the precoding reference signal transmitted by +1 time. Through multiple channel measurements and feedbacks, the precoding vector for data transmission determined by the network device is getting closer and closer to the direction of the terminal device, which is conducive to improving data transmission performance.

Description

A channel measurement method, communication device and computer readable medium

technical field

The present application relates to the field of communication, and more particularly, to a channel measurement method and a communication device.

Background technique

In a massive multiple-input multiple-output (massive multiple-input multiple output, Massive MIMO) technology, a network device can reduce interference between multiple users and interference between multiple signal streams of the same user through a precoding technology. Thereby, signal quality is improved, space division multiplexing is realized, and spectrum utilization is improved.

Currently, a channel measurement method is known. The terminal device can perform channel measurement according to the received reference signal, and determine the precoding vector to be fed back. The reference signal received by the terminal device may be, for example, a precoded reference signal. However, if the precoding vector used by the network device to precode the downlink reference signal is not suitable, the feedback obtained from the terminal device is not accurate enough, and the precoding matrix determined thereby for precoding the downlink data is also inaccurate. It may not be able to adapt to the downlink channel well, and the data transmission performance is degraded.

SUMMARY OF THE INVENTION

The present application provides a channel measurement method and a communication device, in order to select a reasonable precoding vector to precode a downlink reference signal, so as to help obtain more accurate feedback from a terminal device.

In a first aspect, a channel measurement method is provided. The method may be performed by a network device, or may also be performed by a chip configured in the network device. This application does not limit this.

Specifically, the method includes: determining a target precoding vector for data transmission based on feedback information received K times; the feedback information received K times is determined based on precoding reference signals sent K times, wherein the kth The feedback information received for the second time is used to indicate the weight of the N _k precoding vectors, and the weighted sum of the N _k precoding vectors is one precoding vector in the N _k+1 precoding vectors; the N _k precoding vectors The precoding vector is a precoding vector used for generating the precoding reference signal sent at the kth time, and the N _k+1 precoding vectors are the precoding vector used for generating the precoding reference signal sent at the k+1th time ; K≥1, 1≤k≤K, and _k , K, Nk and Nk ₊₁ are all positive integers; perform precoding on the data to be transmitted according to the target precoding vector to obtain the precoded data ; Send the precoded data.

Therefore, the terminal device can perform channel measurement and feedback based on the precoding reference signals sent multiple times by the network device. The precoding reference signal used by the precoding reference signal sent by the network device each time refers to the information fed back by the previous terminal device, so it can get closer and closer to the direction of the terminal device, so that the obtained feedback from the terminal device is more accurate. Precise. In addition, the network device may determine the precoding vector used to precode the data based on the latest feedback from the terminal device, and the precoding vector thus determined may be considered to be the closest to the direction of the terminal device in the currently obtained channel measurement results. The precoding direction is therefore beneficial to improve data transmission performance.

With reference to the first aspect, in some possible implementations of the first aspect, the remaining N _{k +1} -1 precoding vectors in the N k+1 precoding vectors are pre-coding vectors in a predetermined set of precoding vectors. Precoding vector.

In the case that N _k+1 is greater than 1, the network device may select N _k+1 −1 precoding vectors that are not used for precoding the reference signal in the previous one or multiple channel measurements from the set of pre-determined precoding vectors. coding vector, the N _k+1 -1 precoding vectors and the weighted sum of the N _k precoding vectors are used to precode the reference signal sent at the k+1th time, so as to obtain the N _k+1 The weight of the precoding vectors, and the feedback information obtained therefrom can be used to precode the reference signal sent in the k+2th time. By traversing the set of precoding vectors, different precoding vectors can be used to search for the direction of the terminal device. Through multiple iterations, the vector used by the network device to precode the reference signal can get closer and closer to the direction of the terminal device, and the precoding vector used for data transmission thus determined is also closer and closer to the direction of the terminal device.

和基于

构造的多个向量；1≤I≤K且I为正整数。With reference to the first aspect, in some possible implementations of the first aspect, the method further includes: generating a first set of precoding vectors based on the feedback information received at the first time among the feedback information received at the K times, The feedback information received for the first time is used to indicate the weights of N _I precoding vectors, and the N _I precoding vectors are precoding vectors used to generate the precoding reference signal sent for the first time; the The first set of precoding vectors includes a weighted sum determined by the N _I precoding vectors and their weights

and based on

Constructed multiple vectors; 1≤I≤K and I is a positive integer.

Therefore, after the pre-configured pre-coding vector set or the pre-coding vectors in the pre-determined pre-coding vector set are traversed, the network device may further traverse the currently used pre-coding vector set (for example, as described below, based on the feedback information of the terminal device) The second precoding vector set described above) is updated. Since this update is based on the feedback information of the terminal device, the updated first precoding vector set is closer to the direction of the terminal device than the currently used precoding vector set, so it can be in a smaller range. Search for the direction of the terminal device within to get more accurate feedback.

With reference to the first aspect, in some possible implementations of the first aspect, the precoding vector used to generate the precoding reference signal sent for the 1+1th time is the precoding vector in the first precoding vector set; At least part of the precoding vectors in the precoding vectors used to generate the precoding reference signals sent the first time are vectors in a predetermined second precoding vector set; the second precoding vector set is the same as the first precoding vector set. The sets of precoding vectors are different.

The second precoding vector set may be a preconfigured precoding vector set, or may be a precoding vector set obtained after one or more updates. This application does not limit this. Since the second precoding vector is updated, the updated precoding vector in the first precoding vector set is at least partially different from the precoding vector in the second precoding vector set.

为所述第一预编码向量集合中的一个预编码向量；基于

中幅度最大的元素b所在的行，生成T-1个吉文斯Givens旋转矩阵G(c， t，θ)或G(t，c，θ)；其中，c表示b在

中的行索引且c为正整数，1≤c≤T；t 在1至T中取整数值且t≠c，θ表示旋转角度；基于所述T-1个Givens旋转矩阵G(c， t，θ)或G(t，c，θ)，生成所述第一预编码向量集合中的其余T-1个向量。With reference to the first aspect, in some possible implementations of the first aspect, the first precoding vector set includes at least T precoding vectors. The generating the first precoding vector set based on the feedback information received at the I-th time in the feedback information received at the K times includes: based on the feedback information received at the I-th time in the feedback information received at the K times Determine the weighted sum of the N _I precoding vectors

is a precoding vector in the first set of precoding vectors; based on

In the row where the element b with the largest magnitude is located, generate T-1 Givens rotation matrices G(c, t, θ) or G(t, c, θ);

Row index in and c is a positive integer, 1≤c≤T; t takes an integer value in 1 to T and t≠c, θ represents the rotation angle; based on the T-1 Givens rotation matrix G(c, t , θ) or G(t, c, θ) to generate the remaining T-1 vectors in the first precoding vector set.

中幅度最大的元素和其他元素构成的二位向量做轻微的旋转，也就相当于，基于强度最强的方向扩展出多个方向。也就是在一个小的范围内基于更精确地搜索终端设备的方向。in the weighted sum

The two-bit vector formed by the element with the largest amplitude and other elements is slightly rotated, which is equivalent to expanding in multiple directions based on the direction with the strongest intensity. That is, based on a more precise search for the direction of the terminal device within a small range.

With reference to the first aspect, in some possible implementations of the first aspect, the feedback information received for the K times is used to determine a precoding vector used for transmitting the data through the lth transport layer in the L transport layers ; One or more of the L transport layers are used to transmit the data, 1≤1≤L, L≥1, and both l and L are integers.

That is, some or all of the L transport layers may be used to transmit data to the same terminal device. The feedback information received for the above K times may be used to determine a precoding vector for precoding the data transmitted through one of the transport layers. The L transport layers may be determined by the number of transmit antennas configured by the network device. The number of transmit antennas mentioned here may refer to the number of independent transmit and receive units (transceiver units, TxRU).

个预编码向量的权重，所述

个预编码向量的加权和为

个预编码向量中的一个预编码向量；所述

个预编码向量为用于生成第k次通过所述第j个传输层发送的预编码参考信号的预编码向量，所述

个预编码向量为用于生成第k+1次通过所述第j个传输层发送的预编码参考信号的预编码向量；1≤j≤J-1，且j为整数。With reference to the first aspect, in some possible implementations of the first aspect, J transport layers in the L transport layers are used to transmit data, and the J transport layers include the lth transport layer and the For J-1 transport layers other than the lth transport layer, 2≤J≤L, and J is an integer. The method further includes: determining a precoding vector used for transmitting data in the mth transport layer based on the feedback information received K times, where the jth transport layer is one of the J-1 transport layers. Any transmission layer; wherein, the feedback information received in the K times is determined by the precoding reference signal sent on the jth transmission layer in the K times; among the feedback information received in the K times, the feedback information is received in the kth time The feedback information received is used to indicate

weights of precoding vectors, the

The weighted sum of the precoding vectors is

a precoding vector among the precoding vectors; the

The precoding vectors are the precoding vectors used to generate the precoding reference signal transmitted through the jth transport layer for the kth time, and the

The precoding vectors are precoding vectors used to generate the precoding reference signal transmitted by the jth transport layer at the k+1th time; 1≤j≤J-1, and j is an integer.

In the J transport layers, the precoding vector used for precoding the data transmitted on each transport layer may be determined according to the feedback of the terminal device based on the transport layer. The terminal device may carry feedback for multiple transport layers through feedback information sent at one time. It is beneficial for the network device to determine a precoding vector for precoding data transmitted by each transport layer based on the feedback of each transport layer.

With reference to the first aspect, in some possible implementations of the first aspect, the method further includes: receiving a reset indication from a precoding vector set, where the precoding vector set reset indication is used to indicate a reset-based precoding A set of coding vectors for channel measurements.

Therefore, in the case of high-speed movement or channel mutation, the terminal device can suggest that the network device reset the precoding vector set, and then re-measure the channel, so that the direction of the terminal device can be quickly searched and the channel suitable for the channel can be determined. Precoding vector for data transmission.

In a second aspect, a channel measurement method is provided. The method can be executed by a terminal device, or can also be executed by a chip configured in the terminal device. This application does not limit this.

Specifically, the method includes: generating feedback information based on the received precoding reference signal, where the feedback information is used to indicate the weight of one or more precoding vectors used to generate the the precoding vector of the precoding reference signal; and sending the feedback information.

Therefore, the terminal device can perform channel measurement and feedback based on the precoding reference signals sent multiple times by the network device. The precoding reference signal used by the precoding reference signal sent by the network device each time refers to the information fed back by the previous terminal device, so it can get closer and closer to the direction of the terminal device, so that the obtained feedback from the terminal device is more accurate. Precise. In addition, the network device may determine the precoding vector used to precode the data based on the latest feedback from the terminal device, and the precoding vector thus determined may be considered to be the closest to the direction of the terminal device in the currently obtained channel measurement results. The precoding direction is therefore beneficial to improve data transmission performance.

With reference to the second aspect, in some possible implementations of the second aspect, the generating feedback information based on the received precoding reference signal includes: based on a predetermined observation matrix W and the received precoding reference signal , determine the weight of the one or more precoding vectors; wherein, W=S(UΛ) ^-1 ; U and Λ are the matrix obtained by singular value decomposition of the channel matrix H; U is an R-dimensional unitary matrix, and Λ is R A diagonal matrix with rows and T columns; S is a matrix with Z rows and R columns, each row in S includes R-1 zero elements, and the zth element in the zth row in S is 1; 1≤z≤Z, Z represents the rank of the channel matrix H, R represents the number of receiving antennas, z, Z, T and R are all integers; the feedback information is generated based on the weight of the one or more precoding vectors.

The terminal device can accurately calculate the weight of each precoding vector based on the observation matrix and the received precoding reference signal, and feed it back to the network device.

It should be understood that calculating the weight of each precoding vector based on the observation matrix is only a possible implementation manner, and should not constitute any limitation to this application. The present application does not limit the specific implementation manner in which the terminal device determines each precoding vector.

In conjunction with the second aspect, in some possible implementations of the second aspect, the method further includes:

A precoding vector set reset indication is sent, where the precoding vector set reset indication is used to instruct channel measurement based on the reset precoding vector set.

Therefore, in the case of high-speed movement or channel mutation, the terminal device can suggest that the network device reset the precoding vector set, and then re-measure the channel, so that the direction of the terminal device can be quickly searched and the channel suitable for the channel can be determined. Precoding vector for data transmission.

In a third aspect, a communication apparatus is provided, including each module or unit for performing the method in the first aspect and any possible implementation manner of the first aspect.

In a fourth aspect, a communication apparatus is provided, including a processor. The processor is coupled to the memory, and can be configured to execute instructions in the memory, so as to implement the method in the first aspect and any possible implementation manner of the first aspect. Optionally, the communication device further includes a memory. Optionally, the communication device further includes a communication interface, and the processor is coupled to the communication interface.

In an implementation manner, the communication 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.

In another implementation manner, the communication device is a chip configured in the terminal device. When the communication device is a chip configured in the terminal device, the communication interface may be an input/output interface.

Optionally, the transceiver may be a transceiver circuit. Optionally, the input/output interface may be an input/output circuit.

In a fifth aspect, a communication apparatus is provided, including various modules or units for performing the method in the second aspect and any possible implementation manner of the second aspect.

In a sixth aspect, a communication apparatus is provided, including a processor. The processor is coupled to the memory and can be used to execute instructions in the memory to implement the method in the second aspect and any possible implementation manner of the second aspect. Optionally, the communication device further includes a memory. Optionally, the communication device further includes a communication interface, and the processor is coupled to the communication interface.

In one implementation, the communication apparatus is a network device. When the communication device is a network device, the communication interface may be a transceiver, or an input/output interface.

In another implementation manner, the communication device is a chip configured in a network device. When the communication device is a chip configured in a network device, the communication interface may be an input/output interface.

Optionally, the transceiver may be a transceiver circuit. Optionally, the input/output interface may be an input/output circuit.

In a seventh aspect, a processor is provided, including: an input circuit, an output circuit, and a processing circuit. The processing circuit is configured to receive a signal through the input circuit and transmit a signal through the output circuit, so that the processor performs any one of the first to second aspects and the first to second aspects. method in method.

In the specific implementation process, the above-mentioned processor may be one or more chips, the input circuit may be input pins, the output circuit may be output pins, and the processing circuit may be transistors, gate circuits, flip-flops and various logic circuits, etc. . The input signal received by the input circuit may be received and input by, for example, but not limited to, a receiver, the signal output by the output circuit may be, for example, but not limited to, output to and transmitted by a transmitter, and the input circuit and output The circuit can be the same circuit that acts as an input circuit and an output circuit at different times. The embodiments of the present application do not limit the specific implementation manners of the processor and various circuits.

In an eighth aspect, a processing apparatus is provided, including a processor and a memory. The processor is configured to read instructions stored in the memory, and can receive signals through a receiver and transmit signals through a transmitter, so as to perform any one of the first to second aspects and any possible implementation manners of the first to second aspects method in .

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.

In a specific implementation process, the memory may be a non-transitory memory, such as a read only memory (ROM), which may be integrated with the processor on the same chip, or may be separately provided in different On the chip, the embodiment of the present application does not limit the type of the memory and the setting manner of the memory and the processor.

It should be understood that the relevant data interaction process, such as sending indication information, may be a process of outputting indication information from the processor, and receiving capability information may be a process of receiving input capability information by the processor. Specifically, the data output by the processor can be output to the transmitter, and the input data received by the processor can be from the receiver. Among them, the transmitter and the receiver may be collectively referred to as a transceiver.

The processing device in the above eighth aspect may be one or more chips. The processor in the processing device may be implemented by hardware or by software. When implemented by hardware, the processor can be a logic circuit, an integrated circuit, etc.; when implemented by software, the processor can be a general-purpose processor, implemented by reading software codes stored in a memory, which can Integrated in the processor, can be located outside the processor, independent existence.

In a ninth aspect, a computer program product is provided, the computer program product comprising: a computer program (also referred to as code, or instructions), when the computer program is executed, causes the computer to execute the above-mentioned first to sixth aspects The method in the second aspect and any possible implementation manner of the first aspect to the second aspect.

In a tenth aspect, a computer-readable medium is provided, the computer-readable medium is stored with a computer program (also referred to as code, or instruction) when it is run on a computer, so that the computer executes the above-mentioned first to sixth aspects. The method in the second aspect and any possible implementation manner of the first aspect to the second aspect.

In an eleventh aspect, a communication system is provided, including the aforementioned network device and terminal device.

Description of drawings

FIG. 1 is a schematic diagram of a communication system suitable for the channel measurement method provided by the embodiment of the present application;

FIG. 2 is a schematic flowchart of a channel measurement method provided by an embodiment of the present application;

3 is a schematic block diagram of a communication device provided by an embodiment of the present application;

4 is a schematic structural diagram of a terminal device provided by an embodiment of the present application;

FIG. 5 is a schematic structural diagram of a network device provided by 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: global system for mobile communications (GSM) system, code division multiple access (code division multiple access, CDMA) system, wideband code division multiple access (wideband code division multiple access) code division multiple access (WCDMA) system, general packet radio service (GPRS), long term evolution (long termevolution, LTE) system, LTE frequency division duplex (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, future fifth generation (5th generation, 5G) system or new Wireless (new radio, NR) and so on.

To facilitate understanding of the embodiments of the present application, firstly, a communication system applicable to the embodiments of the present application is described in detail by taking the communication system shown in FIG. 1 as an example. FIG. 1 is a schematic diagram of a communication system 100 applicable to the channel measurement method according to the embodiment of the present application. As shown in FIG. 1 , the communication system 100 may include at least one network device, such as the network device 110 shown in FIG. 1 ; the communication system 100 may also include at least one terminal device, such as the terminal device 120 shown in FIG. 1 . Network device 110 and terminal device 120 may communicate over a wireless link. Each communication device, such as the network device 110 or the terminal device 120, may be configured with multiple antennas. For each communication device in the communication system 100, the configured plurality of antennas may include at least one transmit antenna for transmitting signals and at least one receive antenna for receiving signals. Therefore, communication between various communication devices in the communication system 100, such as between the network device 110 and the terminal device 120, can be communicated through the multi-antenna technology.

It should be understood that the network device in the communication system may be any device with a wireless transceiver function. The network equipment 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), access in wireless fidelity (wirelessfidelity, WiFi) systems Access point (AP), wireless relay node, wireless backhaul node, transmission point (TP) or transmission and reception point (TRP), etc., can also be 5G, such as NR, system gNB, or, transmission point (TRP or TP), one or a group (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 transmission point, such as a baseband unit (BBU), or distributed unit (distributed unit, DU), etc.

In some deployments, a gNB may include a centralized unit (CU) and a DU. The gNB may also include an active antenna unit (active antenna unit, AAU for short). CU implements some functions of gNB, DU implements some functions of gNB, for example, CU is responsible for processing non-real-time protocols and services, implementing radio resource control (RRC), packet data convergence protocol (packet data convergence protocol, PDCP) layer function. The DU is responsible for processing physical layer protocols and real-time services, and implementing functions of a radio link control (radio link control, RLC) layer, a media access control (media access control, MAC) layer, and a physical (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 may be divided into network devices in an access network (radio access network, RAN), and the CU may also be divided into network devices in a core network (core network, CN), which is not limited in this application.

It should also be understood that the terminal equipment in the wireless communication system may also be referred to as user equipment (UE), access terminal, subscriber unit, subscriber station, mobile station, mobile station, remote station, remote terminal, mobile equipment, User terminal, terminal, wireless communication device, user agent or user equipment. The terminal device in the embodiments of the present application may be a mobile phone (mobile phone), a tablet computer (pad), a computer with a wireless transceiver function, a virtual reality (virtual reality, VR) terminal device, and an augmented reality (augmented reality, AR) terminal Equipment, wireless terminal in industrial control, wireless terminal in self driving, wireless terminal in remote medical, wireless terminal in smart grid, transportation safety A wireless terminal in a smart city, a wireless terminal in a smart city, a wireless terminal in a smart home, a mobile terminal configured in a vehicle, and so on. The embodiments of the present application do not limit application scenarios.

It should also be understood that FIG. 1 is only a simplified schematic diagram for easy understanding, and the communication system 100 may also include other network devices or other terminal devices, which are not shown in FIG. 1 .

To facilitate understanding of the embodiments of the present application, the following briefly describes the processing process of the downlink signal at the physical layer before sending. It should be understood that the processing of the downlink signal described below may be performed by a network device, or may be performed by a chip configured in the network device. For convenience of description, hereinafter collectively referred to as network devices.

The network device may process code words on the physical channel. The codewords may be coded bits that have been coded (eg, including channel coding). The codeword is scrambled to generate scrambled bits. The scrambled bits are subjected to modulation mapping to obtain modulation symbols. Modulation symbols are mapped to multiple layers, or transport layers, through layer mapping. The modulation symbols after layer mapping are precoded to obtain a precoded signal. The precoded signal is mapped to multiple REs after being mapped by resource elements (resource elements, REs). These REs are then modulated by orthogonal frequency division multiplexing (OFDM) and then transmitted through an antenna port (antenna port).

It should be understood that the processing procedure for the downlink signal described above is only an exemplary description, and should not constitute any limitation to the present application. For the processing process of the downlink signal, reference may be made to the prior art. For the sake of brevity, the detailed description of the specific process is omitted here.

To facilitate understanding of the embodiments of the present application, the following briefly describes terms involved in the embodiments of the present application.

1. Precoding technology: When the channel state is known, the sending device (such as network device) can process the signal to be sent with the help of a precoding matrix that matches the channel state, so that the precoded signal to be sent is different from the channel state. Therefore, the complexity of eliminating the influence between the channels by the receiving device (such as the terminal device) is reduced. Therefore, through the precoding process of the signal to be transmitted, the received signal quality (eg, signal to interference plus noise ratio (SINR), etc.) is improved. Therefore, by using the precoding technology, the transmitting device and multiple receiving devices can transmit on the same time-frequency resource, that is, multiple user multiple input multiple output (MU-MIMO) is realized.

It should be understood that the relevant descriptions about the precoding technology are only examples for ease of understanding, and are not used to limit the protection scope of the embodiments of the present application. In a specific implementation process, the sending device may also perform precoding in other manners. For example, in the case where the channel information (eg, but not limited to, the channel matrix) cannot be obtained, a preset precoding matrix or a weighting processing method is used to perform precoding and the like. For the sake of brevity, the specific content will not be repeated here.

2. Precoding reference signal: also known as a beamformed reference signal. The beamforming reference signal may be a precoded reference signal, which may be similar to a Class B (Class B) reference signal in the LTE protocol. In contrast, the reference signal without precoding processing may be similar to the Class A (Class A) reference signal in the LTE protocol.

In the embodiments of the present application, for the convenience of distinction and description, the precoded reference signal is referred to as a precoded reference signal; the unprecoded reference signal is simply referred to as a reference signal.

It should be understood that the reference signal involved in this embodiment of the present application may be a reference signal used for channel measurement. For example, the reference signal may be a channel state information reference signal (CSI-RS) or a sounding reference signal (SRS). However, it should be understood that the above enumeration is only an example, and should not constitute any limitation to the present application, and the present application does not exclude the possibility of defining other reference signals in future protocols to achieve the same or similar functions.

3. Antenna port: referred to as port. It can be understood as a virtual antenna recognized by the receiving device. Or spatially distinguishable transmit antennas. One antenna port can be configured for each virtual antenna, each virtual antenna can be a weighted combination of multiple physical antennas, and each antenna port can correspond to a reference signal, therefore, each antenna port can be called a port of a reference signal . In this embodiment of the present application, an antenna port may refer to a port of a precoded reference signal.

In this embodiment of the present application, an antenna port may refer to a transmit antenna port. For example, the reference signal for each port may be an unprecoded reference signal. The antenna port may also refer to the reference signal port after precoding, for example, the reference signal of each port may be a precoding reference signal obtained by precoding the reference signal based on a precoding vector. The signal of each port may be transmitted through one or more resource blocks (RBs).

The transmitting antenna port may also be referred to as a transmitting antenna for short. Specifically, it may refer to an actual independent transceiver unit (transceiver unit, TxRU). In this embodiment of the present application, the number of transmit antenna ports may be equal to the number of transceiver units. It can be understood that, if the reference signal is precoded, the number of ports may refer to the number of reference signal ports, and the number of reference signal ports may be smaller than the number of transmit antenna ports. Therefore, by precoding the reference signal, it is possible to reduce the dimension of the transmit antenna port, so as to achieve the purpose of reducing pilot overhead.

In the embodiments shown below, the specific meanings expressed by the ports can be determined according to specific embodiments.

4. Channel matrix and equivalent channel matrix: The receiver can determine the channel through a variety of possible implementations. For example, the receiving end may perform channel estimation according to the received reference signal; for another example, the receiving end may estimate the channel according to the reciprocity of the uplink and downlink channels. This application does not limit this.

As an example of downlink channel estimation, the terminal device can estimate the downlink channel according to the received reference signal. The downlink channel can be denoted as H, for example. The downlink channel can be represented, for example, as a matrix of dimension R×T. Among them, R is the number of receiving antennas, and T is the number of transmitting antenna ports, or the number of TxRUs. Both R and T are positive integers.

If the network device precodes the reference signal, the terminal device can estimate the downlink channel according to the received precoded reference signal. The downlink channel estimated by the terminal equipment from the precoding reference signal is actually a precoded channel, which can be called an equivalent channel. If the precoding vector is b, the equivalent channel estimated by the terminal device can be denoted as _{He eff} , for example, then _{He eff} =Hb. The precoding vector is a vector with a dimension of T×1. It can be seen that when the network device precodes the reference signal based on a precoding vector, the dimension of the equivalent channel estimated by the terminal device is R×1. That is, the dimension reduction of the transmitting antenna port is realized.

5. Precoding vector and precoding vector set: In this embodiment of the present application, a precoding vector refers to a vector used for precoding a reference signal. The precoding vector may be selected from a predetermined set of precoding vectors. The precoding vector set may include multiple optional precoding vectors. Moreover, in this embodiment of the present application, the precoding vectors in the precoding vector set may be updated with the feedback of the terminal device, so as to adapt to the change of the channel and obtain more accurate feedback from the terminal device.

The precoding vector can be, for example, a column vector of length T. The set of precoding vectors may include T column vectors of length T . The T column vectors may be orthogonal to each other pairwise. For example, the T column vectors may be vectors taken from a discrete Fourier transform (DFT) matrix.

In the embodiments of the present application, the precoding vector sometimes refers to a precoding vector used for precoding a reference signal, and sometimes refers to a precoding vector used for precoding data to be transmitted. Those skilled in the present application can understand its specific meaning in different scenarios. In the following embodiments, for ease of distinction and understanding, the precoding vector used for precoding the reference signal is denoted by b, and the precoding vector used for precoding the data to be transmitted is denoted by p. However, these are represented by different letters only for convenience of distinction, and should not constitute any limitation to the present application.

6. Precoding matrix indicator (PMI): take the downlink channel measurement as an example, under normal circumstances, the terminal device can carry the precoding matrix to be fed back determined based on the channel measurement in the channel state information (channel state information) through PMI. state information, CSI) report, so that the network device can determine the precoding vector used for each transport layer when transmitting data through one or more transport layers according to the PMI, or, in other words, determine the precoding used for data transmission according to the PMI matrix.

In this embodiment of the present application, the terminal device may perform channel estimation based on the received precoding reference signals of each port, and obtain an equivalent channel corresponding to each port. The terminal device may feed back an equivalent channel obtained by performing channel estimation based on the precoding reference signal of each port to the network device through the weight of the precoding vector. In order for the network device to know the weight of each precoding vector used for precoding the reference signal, the precoding vector used for precoding the data to be transmitted on each transport layer can be determined, and it can also be used for the next time. The precoding vector is updated when the reference signal is precoded.

It should be noted that when the network device determines the precoding matrix for data transmission based on the PMI, the precoding matrix may be determined directly based on the feedback of the terminal device, or some beamforming methods may be used, such as zero forcing (ZF) , minimum mean-squared error (minimum mean-squared error, MMSE), maximum signal-to-leakage-and-noise (signal-to-leakage-and-noise, SLNR), etc., to obtain a precoding matrix that is finally used for downlink data transmission. This application does not limit this. It should be understood that the beamforming methods listed above are only examples, and should not constitute any limitation to the present application. The precoding matrices used for data transmission mentioned in the following may all refer to precoding matrices determined based on the channel measurement method provided in this application.

7. Transport layer (layer): It can also be called transport stream. The number of transmission layers used for data transmission between the network device and the terminal device may be determined by the rank of the channel matrix. The terminal device may determine the number of transmission layers according to the channel matrix obtained by channel estimation. For example, the precoding matrix may be determined by performing singular value decomposition (SVD) on the channel matrix or the covariance matrix of the channel matrix. In the SVD process, different transport layers can be distinguished according to the size of the eigenvalues. For example, the precoding vector determined by the eigenvector corresponding to the largest eigenvalue may correspond to the first transmission layer, and the precoding vector determined by the eigenvector corresponding to the smallest eigenvalue may be associated with the Lth transmission layer. layer corresponds. That is, the eigenvalues corresponding to the first transport layer to the Lth transport layer decrease sequentially.

It should be understood that distinguishing different transport layers based on characteristic values is only a possible implementation manner, and should not constitute any limitation to the present application. For example, the protocol may also predefine other criteria for distinguishing the transport layer, which is not limited in this application.

In order to obtain better signal transmission quality, the sender hopes to obtain a relatively accurate channel state, and uses a precoding matrix that matches the channel state to process the signal to be sent, so as to eliminate inter-channel interference and improve signal quality.

Take the following line transfer as an example. In some modes, such as time division duplexing (time division duplexing, TDD) mode, the uplink and downlink channels transmit signals on the same frequency domain resource and different time domain resources. Within a relatively short time (eg, the coherence time of channel propagation), it can be considered that the channel fading experienced by the signals on the uplink and downlink channels is the same. This is the reciprocity of the uplink and downlink channels. Based on the reciprocity of the uplink and downlink channels, the network device may measure the uplink channel according to the uplink reference signal, such as a sounding reference signal (sounding reference signal, SRS). And the downlink channel can be estimated according to the uplink channel, so that the precoding matrix used for downlink transmission can be determined.

However, in other modes, such as frequency division duplexing (FDD) mode, since the frequency band spacing of the uplink and downlink channels is much larger than the coherence bandwidth, the uplink and downlink channels do not have complete reciprocity. The precoding matrix determined for downlink transmission may not be able to be adapted to the downlink channel. If the network device still estimates the downlink channel according to the uplink channel measured by the uplink reference signal, the estimated downlink channel may not necessarily be accurate. Therefore, the precoding matrix used for data transmission determined by the network device based on the estimated downlink channel may also be adapted to the real downlink channel. Eventually, the quality of data transmission is degraded and the system performance is degraded.

Based on this, the present application provides a channel measurement method, hoping to obtain a relatively accurate channel state between the transmitting end and the receiving end, so that a reasonable precoding matrix can be selected to precode the data to be transmitted, so as to improve the quality of data transmission, Improve system performance.

In order to facilitate the understanding of the embodiments of the present application, before introducing the embodiments of the present application, the following points are first explained.

First, for the convenience of understanding and description, the main parameters involved in this application are described as follows:

L: The number of transport layers that the network device can use. The number of transmission layers that can be used by the network device may be determined by the number of transmit antenna ports configured by the network device. The number of transmit antenna ports mentioned here may refer to the number of TxRUs. In this embodiment of the present application, L≧1, and L is an integer; the L transport layers may include, for example, the first transport layer to the Lth transport layer.

Z: The number of transport layers that a network device can use when communicating with a terminal device. That is, the rank of the channel matrix. Z can be determined by the channel matrix. The number of transmission layers that can be used when the network device communicates with the terminal device may be determined by the number of transmit antenna ports configured by the network device and the number of receive antennas configured by the terminal device. For example, Z may be less than or equal to the smaller of the number of transmit antenna ports configured by the network device and the number of receive antennas configured by the terminal device. In the embodiments of the present application, L≥Z≥1, and Z is a positive integer.

T: the number of transmitting antenna ports, T is a positive integer;

R: The number of receiving antennas, R is a positive integer.

Second, in this embodiment, for the convenience of description, when numbering is involved, the numbering may start from 1 consecutively. For example, the L transport layers may include the first transport layer to the Lth transport layer, and so on, which will not be illustrated one by one here. Of course, the specific implementation is not limited to this, for example, the numbers can also be consecutively numbered from 0. It should be understood that the above descriptions are all settings for the convenience of describing the technical solutions provided by the embodiments of the present application, and are not intended to limit the scope of the present application.

Third, in the embodiments of the present application, transformations of matrices and vectors are involved in many places. For ease of understanding, a unified description is made here. The superscript T represents the transposition, such as A ^T represents the transpose of the matrix (or vector) A; the superscript H represents the conjugate transpose, for example, A ^H represents the conjugate transpose of the matrix (or vector) A; The superscript * represents the conjugate, for example, A ^* represents the conjugate of the matrix (or vector) A. Hereinafter, for the sake of brevity, descriptions of the same or similar situations are omitted.

Fourth, in this embodiment of the present application, "for indicating" may include direct indicating and indirect indicating. For example, when describing a certain indication information for indicating information I, the indication information may directly indicate I or indirectly indicate I, but it does not mean that the indication information must carry I.

The information indicated by the indication information is called the information to be indicated. In the specific implementation process, there are many ways to indicate the information to be indicated. For example, but not limited to, the information to be indicated can be directly indicated, such as the information to be indicated itself or the information to be indicated. Indicating the index of information, etc. The information to be indicated may also be indirectly indicated by indicating other information, where there is an association relationship between the other information and the information to be indicated. It is also possible to indicate only a part of the information to be indicated, while other parts of the information to be indicated are known or agreed in advance. For example, the indication of specific information can also be implemented by means of a pre-agreed (for example, a protocol stipulated) arrangement order of various information, so as to reduce the indication overhead to a certain extent. At the same time, the common part of each piece of information can also be identified and indicated uniformly, so as to reduce the indication overhead caused by indicating the same information separately. For example, those skilled in the art should understand that a precoding matrix is composed of precoding vectors, and each precoding vector in the precoding matrix may have the same parts in terms of composition or other properties.

In addition, the specific indication manner may also be various existing indication manners, such as, but not limited to, the above indication manner and various combinations thereof. For the specific details of the various indication modes, reference may be made to the prior art, and details are not described herein again. It can be seen from the above that, for example, when multiple pieces of information of the same type need to be indicated, different information may be indicated in different manners. In the specific implementation process, the required indication mode can be selected according to specific needs. The selected indication mode is not limited in this embodiment of the present application. In this way, the indication mode involved in the embodiment of the present application should be understood as covering the ability to make the indication to be indicated. Various methods for the party to learn the information to be indicated.

In addition, the information to be indicated may have other equivalent forms. For example, a row vector can be represented as a column vector, a matrix can be represented by a transposed matrix of the matrix, and a matrix can also be represented in the form of a vector or an array. The vector or array It can be formed by connecting each row vector or column vector of the matrix, and the Kronecker product of two vectors can also be expressed by the product of one vector and the transposed vector of another vector, etc. The technical solutions provided in the embodiments of the present application should be understood to cover various forms. For example, some or all of the features involved in the embodiments of the present application should be understood to cover various manifestations of the feature.

The information to be indicated may be sent together as a whole, or may be divided into multiple sub-information and sent separately, and the transmission periods and/or transmission timings of these sub-information may be the same or different. The specific sending method is not limited in this application. The sending period and/or sending timing of these sub-information may be predefined, for example, predefined according to a protocol, or configured by the transmitting end device by sending configuration information to the receiving end device. The configuration information may include, for example, but not limited to, radio resource control signaling, such as RRC signaling, MAC layer signaling, such as MAC-CE signaling, and physical layer signaling, such as downlink control information (DCI) one or a combination of at least two.

Fifth, in the embodiments shown below, the first, second, and various numeral numbers are only used to distinguish for convenience of description, and are not used to limit the scope of the embodiments of the present application. For example, distinguishing different sets of precoding vectors, etc.

Sixth, "pre-defined" or "pre-configured" can be achieved by pre-saving corresponding codes, forms or other means that can be used to indicate relevant information in the equipment (for example, including terminal equipment and network equipment). The specific implementation manner is not limited. Wherein, "saving" may refer to saving in one or more memories. The one or more memories may be provided separately, or may be integrated in an encoder or decoder, a processor, or a communication device. The one or more memories may also be partially provided separately and partially integrated in the decoder, processor, or communication device. The type of memory may be any form of storage medium, which is not limited in this application.

Seventh, the “protocol” involved in the embodiments of this application may refer to standard protocols in the communication field, such as LTE protocols, NR protocols, and related protocols applied in future communication systems, which are not limited in this application.

Eighth, "at least one" means one or more, and "plurality" means two or more. "And/or", which describes the association relationship of the associated objects, indicates that there can be three kinds of relationships, for example, A and/or B, which can indicate: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A, B can be singular or plural. The character "/" generally indicates that the associated objects are an "or" relationship. "At least one item(s) below" or similar expressions thereof refer to any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one (a) of a, b and c may represent: a, or, b, or, c, or, a and b, or, a and c, or, b and c, or, a , b and c. Where a, b and c can be single or multiple respectively.

The channel measurement method provided by the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

The methods provided in the embodiments of the present application can be applied to a system that communicates through a multi-antenna technology. For example, the communication system 100 shown in FIG. 1 . The communication system may include at least one network device and at least one terminal device. Communication between network equipment and terminal equipment is possible through multi-antenna technology.

It should be understood that the methods provided in the embodiments of the present application are not limited to the communication between the network device and the terminal device, and can also be applied to the communication between the terminal device and the terminal device, and the like. The present application does not limit the scenarios in which the method is applied. In the embodiments shown below, for ease of understanding and description, the channel measurement method provided by the embodiments of the present application is described in detail by taking the interaction between a network device and a terminal device as an example.

It should also be understood that the embodiments shown below do not particularly limit the specific structure of the execution body of the method provided by the embodiment of the present application, as long as the program that records the code of the method provided by the embodiment of the present application can be executed according to the present application. The method provided by the embodiment of the application can be used for communication. For example, the execution body of the method provided by the embodiment of the present application may be a terminal device or a network device, or a functional module in the terminal device or network device that can call and execute a program.

FIG. 2 is a schematic flowchart of a channel measurement method 200 provided by an embodiment of the present application, shown from the perspective of device interaction. Specifically, the method 200 shown in FIG. 2 is an example of downlink channel measurement. As shown, the method 200 may include steps 210 to 270 . Each step in the method 200 is described in detail below.

In step 210, the network device sends a precoding reference signal, where the precoding reference signal is obtained by precoding the reference signal based on N precoding vectors.

where N≥1 and is an integer. Specifically, the N precoding vectors may be determined from a predetermined set of precoding vectors, for example. The precoding vector set may be, for example, a preconfigured precoding vector set, or a precoding vector set obtained after updating the preconfigured precoding vector set according to feedback information from the terminal device. This application does not limit this.

The network device precodes the reference signal based on the N precoding vectors, and the obtained precoding reference signal may correspond to the N reference signal ports. Each reference signal port corresponds to a precoding vector. That is, the reference signal that the terminal device can identify is the precoded reference signal of N ports. Since the specific process of precoding the reference signal by the network device based on the precoding vector may refer to the prior art, it is not repeated here for brevity.

In one possible design, the network device may precode the reference signal transmitted through each of the L transport layers based on the N precoding vectors. In other words, the precoding reference signal transmitted through any one of the L transport layers may be obtained by precoding the reference signal based on the N precoding vectors. The precoding reference signal transmitted by each of the L transport layers corresponds to N ports.

In another possible design, the network device may perform precoding on the transmission secondary reference signal of a certain transport layer among the L transport layers based on the N precoding vectors. In other words, the N precoding vectors correspond to one of the L transport layers, and the precoding reference signal transmitted on the transport layer is obtained by precoding the reference signal based on the N precoding vectors . The precoding reference signals transmitted on the transport layer correspond to N ports.

Therefore, the reference signals sent by the network device through each transport layer may use different precoding vectors to precode the reference signals respectively. For example, the network device may use N1 (ie, an instance of N) precoding vectors to precode the reference signal through the reference signal sent by the _lth transport layer. It should be understood that the reference signals sent through different transport layers may be precoded using different precoding vectors respectively, and the number of precoding vectors corresponding to each transport layer may be different from each other, may be partially the same, or may be completely the same. . This application does not limit this.

It should be noted that the reference signals transmitted by the network device through the L transport layers may be reference signals sent to the same terminal device, or may be reference signals sent to different terminal devices. This application does not limit this. However, it can be understood that the precoding reference signal transmitted by the network device through a certain transport layer, for example, the precoding reference signal transmitted through the lth transport layer in the L transport layers, is the reference signal sent to the same terminal device. Signal. Wherein, the lth transport layer may be any one of the L transport layers.

In the embodiments of the present application, for ease of understanding and description, it is assumed that the precoding reference signal obtained by the network device precoding the reference signal based on N precoding vectors is the reference signal sent to the same terminal device. The reference signal sent by the network device to the same terminal device may be transmitted through one or more transport layers. When the reference signal sent by the network device to the same terminal device is transmitted through multiple transport layers, the precoded reference signal transmitted by each transport layer may be obtained by precoding the reference signal based on the same N precoding vectors, or it may be obtained in different The reference signal is obtained by precoding the reference signal based on different precoding vectors on the transport layer. In the following, for the convenience of distinction and description, it is assumed that the precoding reference signal received by the terminal device on the lth transmission layer is obtained by precoding the reference signal based on N precoding vectors.

In step 220, the terminal device generates feedback information, where the feedback information is determined based on the precoding reference signal received by the terminal device.

As mentioned above, the reference signals that the terminal device can identify on one transport layer are the precoding reference signals of N ports, that is, the reference signals corresponding to the N precoding vectors. The terminal device may perform channel measurements based on the precoding reference signal of each port to determine feedback information.

In a possible implementation manner, the terminal device may generate feedback information based on a predetermined observation matrix and a received precoding reference signal.

Specifically, the terminal device may construct an observation matrix based on the channel matrix. First, the terminal device can estimate the downlink channel. The downlink channel specifically refers to a downlink channel without precoding, that is, the downlink channel H described above. For example, the terminal device may estimate the downlink channel according to the unprecoded reference signal sent by the network device. Alternatively, the terminal device may also estimate the downlink channel H according to the reciprocity of the uplink and downlink channels. This application does not limit this.

Performing singular value decomposition on the downlink channel H can obtain: H=UΛV ^H . Among them, U is an R-dimensional unitary matrix, V is a T-dimensional unitary matrix, and Λ is a diagonal matrix with R rows and T columns. The observation matrix W can be:

[1 0 … 0]为一行R列的矩阵，该W可适用于R≥1；When the rank is 1,

[1 0 ... 0] is a matrix with one row and R columns, and this W can be applied to R≥1;

为二行R列的矩阵，该W可适用于R≥2；When the rank is 2,

is a matrix with two rows and R columns, this W can be applied to R≥2;

为三行R列的矩阵，该W可适用于R≥3；When the rank is 3,

is a matrix with three rows and R columns, this W can be applied to R≥3;

为L行R列的矩阵，该W可适用于R≥L。And so on, when the rank is L,

is a matrix with L rows and R columns, the W can be applied for R≥L.

According to the observation matrix W listed above when the rank is different, the observation matrix W can be represented by the general formula W=S(UΛ) ^-1 . Among them, S is a matrix with Z rows and R columns. Each row in S includes R-1 zero elements, and the z-th element in the z-th row in S is 1. Z represents the rank of the channel matrix. That is, the network device can communicate with the terminal device through at most Z transport layers. z represents the zth transport layer among the Z transport layers, 1≤z≤Z, Z≤L, and both z and Z are positive integers.

The equivalent channel Hb can be estimated from the reference signal port corresponding to a certain precoding vector b. Then the terminal device left-multiplies the equivalent channel by the observation matrix W, that is, WHb. Then the terminal device can obtain L observations.

It is assumed that the network device sends the precoding reference signal to the terminal device through two transport layers, that is, M=2. but:

If V=[v ₁ v ₂ ... v _T ], then

和

可以称为观测值。

为α_b,1的共轭，

为α_b,2的共轭。α_b,1可以表示针对第1个传输层反馈的预编码向量b的权重，α_b,2可以表示针对第2个传输层反馈的预编码向量b的权重。in,

and

can be called observations.

is the conjugate of α _b,1 ,

is the conjugate of α _b,2 . α _b,1 may represent the weight of the precoding vector b fed back for the first transport layer, and α _b,2 may represent the weight of the precoding vector b fed back for the second transport layer.

It can be understood that, when the network device transmits data through a certain transmission layer, the precoding vector used for precoding the data can be determined according to the weight of each precoding vector for precoding the reference signal fed back by the terminal device. For the convenience of distinction and description, the precoding vector used for precoding data is denoted as a target precoding vector hereinafter.

则可以确定用于对数据做预编码的目标预编码向量，该目标预编码向量例如可以为

或者对该向量p进行处理(如，迫零、MMSE或SLNR等处理)后得到的向量。在本申请实施例中，为方便理解和说明，将由N个预编码向量的加权所得到的向量作为目标预编码向量。但应理解，这不应对本申请构成任何限定。对该N个预编码向量的加权和进行处理的具体方法可以参考现有技术，并且该处理过程是网络设备的内部实现行为，本申请对此不作限定。For example, the weights fed back to N precoding vectors b ₁ , b ₂ , ..., b _N are respectively

Then the target precoding vector for precoding the data can be determined, and the target precoding vector can be, for example,

Or a vector obtained after processing the vector p (eg, zero-forcing, MMSE or SLNR, etc.). In the embodiments of the present application, for the convenience of understanding and description, a vector obtained by weighting N precoding vectors is used as a target precoding vector. However, it should be understood that this should not constitute any limitation to the present application. For a specific method of processing the weighted sum of the N precoding vectors, reference may be made to the prior art, and the processing process is an internal implementation behavior of the network device, which is not limited in this application.

Therefore, the weight of the precoding vector b fed back for the first transport layer may refer to the weight of the precoding vector b used to generate the target precoding vector when data is transmitted through the first transport layer; The weight of the precoding vector b fed back by the second transport layer may refer to the weight of the precoding vector b used to generate the target precoding vector when data is transmitted through the second transport layer.

It can be seen from this that the observation matrix can convert the R received signals corresponding to the same reference signal port on the R receiving antennas into Z observations, thereby reducing the amount of feedback.

和针对第2个传输层反馈的该预编码向量b₁的权重

由预编码向量b_N生成的预编码参考信号经信道测量可以得到：针对第1个传输层反馈的预编码向量b_N的权重

和针对第2个传输层反馈的预编码向量b_N的权重

以此类推，这里不一一列举。As mentioned above, when the reference signal sent by the network device to the same terminal device is transmitted through multiple transport layers, the precoded reference signal transmitted by each transport layer can be obtained by precoding the reference signal based on the same N precoding vectors. It is assumed that the N precoding vectors are denoted as b ₁ , b ₂ , ..., b _N respectively, and the number of transmission layers is 2. Then, it can be considered that the precoding reference signal generated by the network device through the N precoding vectors can be used to perform channel measurement on the channels of the two transmission layers. The terminal device may respectively indicate the weight of each precoding vector in the N precoding vectors at each transmission layer through the feedback information. For example, the precoding reference signal generated by the precoding vector b ₁ can be obtained through channel measurement: the weight of the precoding vector b ₁ fed back for the first transport layer

and the weight of the precoding vector b ₁ fed back for the second transport layer

The precoding reference signal generated by the precoding vector b _N can be obtained through channel measurement: the weight of the precoding vector b _N fed back for the first transport layer

and the weight of the precoding vector b _N fed back for the second transport layer

And so on, not listed here.

用于对第2个传输层上的参考信号做预编码的N₂个预编码向量可以记作

则终端设备可以基于第1个传输层上接收到的N₁个端口的预编码参考信号进行信道测量，以确定该N₁个预编码向量的权重

终端设备还可以基于第2个传输层上接收到的N₂个端口的预编码参考信号进行信道测量，以确定该N₂个预编码向量的权重

When the reference signal sent by the network device to the same terminal device is transmitted through multiple transport layers, the precoded reference signal transmitted by each transport layer may be obtained by precoding the reference signal based on different precoding vectors. Assuming that the number of transmission layers is 2, the N ₁ precoding vectors used to precode the reference signal on the first transmission layer can be written as

The N ₂ precoding vectors used to precode the reference signal on the second transport layer can be written as

Then the terminal device can perform channel measurement based on the precoding reference signals of the N1 ports received on the _first transport layer to determine the weights _of the N1 precoding vectors

The terminal device may also perform channel measurement based on the precoding reference signals of the N ₂ ports received on the second transport layer to determine the weights of the N ₂ precoding vectors

对每个传输层的信道单独进行测量。终端设备基于第1 个传输层上接收到的预编码参考信号测量所得的观测值可用于确定N₁个预编码向量的权重，终端设备基于第2个传输层上接收到的预编码参考信号测量所得的观测值可用于确定 N₂个预编码向量的权重。Since the precoding vector corresponding to each transmission layer is different, the terminal device can use the observation matrix corresponding to the number of transmission layers to be 1 based on the observation matrix.

Measurements are made individually for each transport layer channel. The observations made by the terminal device based on the precoding reference signal received on the first transport layer can be used to determine the weights of the N ₁ precoding vectors, and the terminal device based on the precoding reference signal measured on the second transport layer The resulting observations can be used to determine the weights of the _N2 precoding vectors.

The terminal device may also perform channel measurement based on the corresponding observation matrix when the number of transmission layers is greater than 1. The first observation value (that is, the first observation value corresponding to the first observation value) (that is, the observation value corresponding to the plurality of transmission layers) measured by the terminal device based on the precoding reference signal received on the first transmission layer. The observation value corresponding to the transmission layer) can be used to determine the weight of the N ₁ precoding vectors, and the terminal equipment is based on the precoding reference signal received on the second transmission layer. The first observation value (that is, the observation value corresponding to the first transmission layer) in the observation value corresponding to the first transmission layer) can be used to determine the weight of the N ₂ precoding vectors.

In another possible implementation manner, the terminal device may determine the difference between the signal strength of each precoding reference signal relative to the strength of the precoding reference signal with the highest strength according to the received signal strength of the precoding reference signal of each port ratio, and then generate feedback information. That is, the feedback information can be used to indicate the ratio of the signal strengths of the precoding reference signals of the multiple ports. Since the ratio of the signal strengths of the precoding reference signals of the multiple ports can reflect which direction is closer to the direction of the terminal device to a certain extent, the feedback information can be used to indicate the direction corresponding to each port in the direction close to the terminal device. The weight of the precoding vector.

It should be understood that the implementation manner of determining the weight of each precoding vector according to the received precoding reference signal listed above is only an example, and should not constitute any limitation to the present application. For a specific implementation of the terminal device generating feedback information according to the received precoding reference signal, reference may also be made to the channel measurement method in the prior art. For brevity, the descriptions are not listed here.

Thereafter, the terminal device may generate feedback information based on the determined weights of each precoding vector. As described above, the observation value determined by the terminal device through the observation matrix is the conjugate of the weight of each precoding vector. When generating feedback information, the terminal device may directly feed back the conjugate of each observation value (that is, the weight of each precoding vector) to the network device.

Take N precoding vectors for precoding the reference signal as an example. In an implementation manner, the terminal device may determine, from the multiple weights corresponding to the N ports, the element with the largest modulus value as the normalization coefficient. The magnitude of the element with the largest modulus value is defined as 1, and the phase is defined as 0. The terminal device may further calculate the relative magnitude and relative phase of the other elements with respect to the normalization coefficient. The terminal device may quantize the relative magnitude and relative phase of the other elements with respect to the normalization coefficient to generate feedback information. The feedback information may include, for example, an index of a normalization coefficient and quantized values of relative magnitude and relative phase of other elements with respect to the normalization coefficient.

It should be understood that there may be many specific methods for the terminal device to calculate the relative amplitude and relative phase of other elements with respect to the normalization coefficient. For example, it can be determined by means of difference or inner product. This application does not limit this. It should also be understood that the above-described manner for generating feedback information for multiple weights may be referred to as a normalization manner. Reference may be made to the prior art for a specific method for a terminal device to generate feedback information by using a normalized direction. For the sake of brevity, the detailed description of the specific process is omitted here.

It should also be understood that the method for the terminal device to generate feedback information in a normalized manner is only a possible implementation manner, and should not constitute any limitation to the present application. The terminal device may also quantize the weight of each precoding vector to generate feedback information.

In step 230, the terminal device sends the feedback information. Correspondingly, in step 230, the network device receives the feedback information.

Specifically, the terminal device may carry the feedback information through the PMI in the CSI report, for example. The terminal device may also carry the feedback information through other signaling. The signaling used to carry the feedback information may be existing signaling or newly added signaling. This application does not limit this.

The terminal equipment can send the feedback information to the network equipment through physical uplink resources, such as physical uplink shared channel (physical uplink share channel, PUSCH) or physical uplink control channel (physical uplink control channel, PUCCH), so that the network equipment can send the feedback information according to the feedback information. Determines the target precoding vector for data transmission.

The specific method for the terminal device to send the first indication information to the network device through the physical uplink resource may be the same as that in the prior art. For brevity, the detailed description of the specific process is omitted here.

The weights of the multiple precoding vectors fed back by the terminal device may also be used to determine the precoding vector for the next generation of the precoding reference signal.

In step 240, the network device determines a precoding vector for generating a precoding reference signal to be sent next time according to the feedback information.

The following still takes N precoding vectors as an example to describe the specific process of the network device determining the precoding vector for generating the precoding reference signal next time.

In order to facilitate the distinction, the N precoding vectors are denoted as N _k precoding vectors, then the N _k precoding vectors are the precoding vectors used for the kth channel measurement, and the data sent by the terminal equipment is used to indicate the The feedback information of the weights of the N _k precoding vectors is the feedback information transmitted at the kth time. It can be understood that the feedback information sent at the kth time is obtained by performing channel measurement based on the precoding reference signal sent by the network device at the kth time, and the precoding reference signal sent at the kth time may be based on N _k precoding vectors. It is obtained by precoding the reference signal.

In this embodiment of the present application, the weights of the N _k precoding vectors may be used to determine the precoding reference signal sent at the k+1th time. The number of precoding vectors used to generate the precoding reference signal transmitted at the k+1th time is _Nk+1 , and _Nk+1 is a positive integer.

In an implementation manner, the network device may determine one precoding vector among the N _k+1 precoding vectors based on the N _k precoding vectors and the weights of the N _k precoding vectors. The other N _{k +1} −1 precoding vectors among the N k+1 precoding vectors may be taken from a predetermined set of precoding vectors.

Specifically, the weighted sum b ^(k) may be determined based on the N _k precoding vectors and the weights of the N _k precoding vectors. The weighted sum b ^(k) can be used as one precoding vector among N _k+1 precoding vectors. It can be understood that the weighted sum b ^(k) may be the same as the target precoding vector p described above. This is because the above target precoding vector p is also obtained by weighting the target precoding vector.

The other N _{k +1} −1 precoding vectors among the N k+1 precoding vectors may be taken from a predetermined set of precoding vectors. The predetermined precoding vector set may be, for example, a preconfigured precoding vector set, or a precoding vector set updated based on feedback information from the terminal device.

It can be understood that when N _k+1 is 1, the network device may directly determine the precoding vector used for precoding the reference signal from the weighted sum of the N _k precoding vectors.

The specific process of updating the precoding vector set by the network device according to the feedback information sent by the terminal device will be described in detail below. For the convenience of distinction and description, the precoding vector set updated by the network device is denoted as the first precoding vector set, and the unupdated precoding vector set is denoted as the second precoding vector set.

The first set of precoding vectors may be a set of precoding vectors updated by the network device based on the feedback information received for the first time. That is, k=I, I≦K, and I is a positive integer. The feedback information received for the first time is used to indicate the weights of the N _I precoding vectors, and the N _I precoding vectors are precoding vectors used to generate the precoding reference signal sent the first time. The feedback information received for the first time can be used to determine the precoding vector used to generate the first precoding vector set.

由于该加权和

是基于由N_I个预编码向量对参考信号预编码而生成的预编码参考信号进行信道测量得到，基于该加权和

对信号做预编码所发射的信号方向也就无限接近于终端设备的方向。网络设备可以基于该方向做轻微的扰动，可以得到多个向量。Specifically, the network device may determine the weighted sum of N _I precoding vectors based on the feedback information received for the Ith time

Due to this weighted sum

is obtained by channel measurement based on the precoding reference signal generated by precoding the reference signal with N _I precoding vectors, and based on the weighted sum

The direction of the signal transmitted by precoding the signal is infinitely close to the direction of the terminal device. The network device can make a slight perturbation based on this direction, and can obtain multiple vectors.

中幅度最大的元素b所在的行，生成T-1个吉文斯(Givens)旋转矩阵G(m，t，θ)或G(t，m，θ)。m表示b在

中的行索引且 m为正整数，1≤m≤T；t在1至T中取整数值且t≠c，θ表示旋转角度。基于该T-1个 Givens旋转矩阵G(m，t，θ)或G(t，m，θ)，可以生成第一预编码向量集合中的另外N_k+1-1个预编码向量。For example, a network device may be based on a weighted sum

In the row where the element b with the largest magnitude is located, generate T-1 Givens rotation matrices G(m, t, θ) or G(t, m, θ). m means that b is in

The row index in and m is a positive integer, 1≤m≤T; t takes an integer value in 1 to T and t≠c, θ represents the rotation angle. Based on the T-1 Givens rotation matrices G(m, t, θ) or G(t, m, θ), additional N _k+1 −1 precoding vectors in the first set of precoding vectors may be generated.

The Givens rotation matrix G can be a matrix with T rows and T columns. For a matrix G(p, q, θ), let the row index p be m, and the column index q can be traversed from 1 to T to take values, G(m, m, θ)=G(q, q, θ)=cosθ , -G(m,q,θ)=G(q,m,θ)=sinθ. Other diagonal elements are 1 and off-diagonal elements are 0.

then the matrix

Based on the Givens rotation matrix G(m, t, θ), the T×T matrix S can be constructed as follows:

中两个元素(m， t)所组成的二维向量做轻微的旋转。例如，θ＝π/10。The matrix S includes a total of T column vectors, and each column vector is a T-dimensional vector; θ is used to sequentially

The two-dimensional vector composed of the two elements (m, t) in , is slightly rotated. For example, θ=π/10.

Based on the Givens rotation matrix G(t, m, θ), the T×T matrix S can be constructed as follows:

中两个元素(t， m)所组成的二维向量做轻微的旋转。例如，θ＝π/10。The matrix S includes a total of T column vectors, and each column vector is a T-dimensional vector; θ is used to sequentially

The two-dimensional vector composed of the two elements (t, m) in , is slightly rotated. For example, θ=π/10.

以及由该加权和构造的另外T-1个预编码向量。终端设备可以进一步检验该T个列向量是否线性相关，即，矩阵S是否满秩。若满秩，则对该矩阵S中的T个线性无关的列向量进行施密特正交化，得到第一预编码向量集合所构成的矩阵

上角标(1)表示进行了一次更新后得到的预编码向量集合所构成的矩阵。这里所说的由预编码向量集合所构成的矩阵，可以是指将各列向量按照预定顺序排列而得到的矩阵。由T个T维预编码向量构成的矩阵，可以是维度为T×T的矩阵。Each vector in the matrix S constructed by the above-mentioned Givens rotation matrix includes the weighted sum of the above-mentioned N _I precoding vectors

and another T-1 precoding vectors constructed from this weighted sum. The terminal device can further check whether the T column vectors are linearly correlated, that is, whether the matrix S is of full rank. If the rank is full, perform Schmitt orthogonalization on the T linearly independent column vectors in the matrix S to obtain a matrix formed by the first set of precoding vectors

The superscript (1) represents a matrix formed by a set of precoding vectors obtained after one update. The matrix formed by the set of precoding vectors mentioned here may refer to a matrix obtained by arranging each column vector in a predetermined order. The matrix composed of T T-dimensional precoding vectors may be a matrix with a dimension of T×T.

Therefore, by updating the second precoding vector set, the obtained first precoding vector set may include at least T precoding vectors. Optionally, the first set of precoding vectors includes T precoding vectors. Optionally, the first precoding vector set includes o×T precoding vectors, where o is an oversampling factor. The o×T precoding vectors may be generated, for example, by interpolating the above-mentioned T precoding vectors at equal intervals. For the specific implementation of oversampling, reference may be made to the prior art, which is not limited in this application.

It can be understood that at least some of the vectors in the first precoding vector set obtained after updating and the second precoding vector set are different.

In addition, some or all of the precoding vectors in the above-mentioned N _I precoding vectors may be precoding vectors obtained from the second precoding vector set.

For example, the N _I precoding vectors may all be taken from the second set of precoding vectors. In this case, I may be 1, that is, the precoding reference signal sent at the first time may be the precoding reference signal sent at the first time. The feedback information received for the first time may be the feedback information received for the first time. The second precoding vector set may be, for example, a preconfigured precoding vector set.

For another example, one of the N _I precoding vectors may be the weighted sum of N _I-1 precoding vectors determined according to the feedback information received from the terminal device last time, and the other N _I -1 The precoding vectors may be taken from the second set of precoding vectors. The N _I-1 precoding vectors are the precoding vectors that the network device generates for the precoding reference signal sent at the I-1th time. In this case, I may be greater than 1. The second precoding vector set may be, for example, a preconfigured precoding vector set, or an updated precoding vector set. This is equivalent to repeating the above-mentioned process of updating the precoding vector set. After each update of the precoding vector set is completed, the first precoding vector set obtained after the update is converted into the second precoding vector set when the precoding reference signal is generated next time. After one or more times of feedback from the terminal device, the network device may update the second set of precoding vectors again.

The above steps 210 to 240 may be repeated for many times. Therefore, the precoding vector determined by the network device and used for precoding the reference signal is getting closer and closer to the direction of the terminal device, so that more accurate feedback from the terminal device can be obtained.

In the process of channel measurement, the network device can also transmit data with the terminal device at the same time. For example, after the above steps 210 to 240 are repeatedly performed K times, the network device may determine the target precoding vector for data transmission based on the feedback information received at the Kth time.

As an embodiment, the network device may select a precoding vector for precoding the reference signal based on a preconfigured precoding vector set (for example, denoted as an initial precoding vector set, that is, an example of the second precoding vector set). . For example, the initial precoding vector set includes precoding vectors b ₁ , b ₂ , ..., b _T . The network device may select N precoding vectors from the T precoding vectors to precode the reference signal sent for the first time, where N<T and both N and T are integers.

For example, the network device selects N precoding vectors b ₁ , b ₂ , ..., b _N from the initial precoding vector set to precode the reference signal transmitted through the lth transport layer, then the N precoding vectors The coding vectors can be denoted as b _1,l , b _2,l , . . . , b _N,l . After precoding the reference signal, the network device sends the precoding reference signal through the lth transport layer. _The precoding reference signal generated by the network device based on the N precoding vectors b _1,1 , b _2,1 , . precoding reference signal.

网络设备可以基于该N个预编码向量的权重确定用于下一次对参考信号做预编码的一个预编码向量为

网络设备可以进一步从初始预编码向量集合中剩余的T-N个预编码向量中选择N-1个预编码向量(这里暂且假设T-N≥N-1)，该N-1个预编码向量例如分别记作b_N+1，b_N+2，……，b_2N-1。由于该N-1个预编码向量用于对通过第l个传输层传输的参考信号做预编码，故可以记作 b_N+1,l，b_N+2,l，……，b_2N-1,l。该N-1个预编码向量和上述b_l ⁽¹⁾可构成新的N个预编码向量，用于对网络设备通过第l个传输层传输的参考信号做预编码。网络设备在对参考信号做预编码后，通过该第l个传输层发送预编码参考信号。网络设备基于该N个预编码向量

b_N+1,l，b_N+2,l，……，b_2N-1,l生成的预编码参考信号可以看成是网络设备通过第l个传输层第2次发送的预编码参考信号。The terminal device performs channel measurement based on the precoding reference signal received at the lth transmission layer, and feeds back the weights of the N precoding vectors as

The network device may determine, based on the weights of the N precoding vectors, a precoding vector for precoding the reference signal next time as:

The network device may further select N-1 precoding vectors from the remaining TN precoding vectors in the initial precoding vector set (it is assumed here that TN≥N-1), and the N-1 precoding vectors are respectively denoted as b _N+1 , b _N+2 , ..., b _2N-1 . Since the N-1 precoding vectors are used for precoding the reference signal transmitted through the lth transport layer, they can be denoted as b _N+1,1 , b _N+ 2,1 ,...,b _{2N- 1,l} . The N-1 precoding vectors and the above b _l ⁽¹⁾ may form new N precoding vectors, which are used for precoding the reference signal transmitted by the network device through the lth transport layer. After precoding the reference signal, the network device sends the precoding reference signal through the lth transport layer. The network device is based on the N precoding vectors

The precoding reference signal generated by b N+ _1,1 , b _N+2,1 ,...,b _2N-1,1 can be regarded as the precoding reference signal sent by the network device for the second time through the lth transport layer .

和初始预编码向量中的N-1个预编码向量b_k(N-1)+2，b_k(N-1)+3，……，b_(k+1)(N-1)+1对通过第l个传输层传输的参考信号做预编码得到。By analogy, as long as there are enough precoding vectors in the initial precoding vector set, the network device can repeatedly perform the above operations. For example, the precoding reference signal sent by the network device at the k+1th time may be based on

and the N-1 precoding vectors in the initial precoding vector b _k(N-1)+2 , b _k(N-1)+3 , ..., b _(k+1)(N-1)+1 Obtained by precoding the reference signal transmitted through the lth transport layer.

Since the number of precoding vectors in the initial precoding vector set is limited, when the number N' of the remaining precoding vectors (that is, the precoding vectors without precoding) in the initial precoding vector set is less than N-1 , the network device may also precode the reference signal transmitted through the lth transport layer based on the N' precoding vectors and the vector weighted based on the feedback information received last time. The precoding reference signal sent this time can be understood as an example of the precoding reference signal sent for the first time described above.

The terminal device may perform channel measurement and send feedback information based on the precoding reference signal received on the lth transport layer to indicate the weight of each precoding vector. The feedback information sent by the terminal device this time can be understood as an example of the above-mentioned feedback information sent for the first time. After receiving the feedback information from the terminal device, the network device may update the initial precoding vector to obtain an updated precoding vector set (ie, an example of the first precoding vector set described above). The specific process of updating the precoding vector set by the network device has been described in detail above, and for the sake of brevity, it will not be repeated here.

Therefore, based on multiple measurements and feedbacks between the network device and the terminal device, the feedback of the terminal device for the lth transport layer is getting closer and closer to the terminal device, so it is used to precode the data transmitted by the lth transport layer. The target precoding vector of , can also be better adapted to the channel.

In a possible design, the matrix formed by the foregoing initial precoding vector set is a unitary matrix. Let Ψ ⁽⁰⁾ = [b ₁ b ₂ ... b _T ], then Ψ ⁽⁰⁾ is a unitary matrix. The superscript (0) represents a precoding vector set that has not been updated, or a preconfigured precoding vector set.

It should be noted that the operation of precoding the reference signal by the network device based on the initial precoding vector set is not limited to precoding the reference signal transmitted on one transport layer. When the network device transmits reference signals through multiple transport layers, the reference signals transmitted through each transport layer may be obtained based on different numbers and different precoding vectors. For example, for transport layers 1 and z, the network device may first select multiple precoding vectors from the initial precoding vector set to perform the operation on the reference signal transmitted through the lth transport layer and the reference signal transmitted through the zth transport layer respectively. precoding. The terminal device may perform channel measurement based on the precoding reference signal received on the lth transport layer and the precoding reference signal received on the zth transport layer, and send feedback information to the network device.

这N_l个预编码向量对通过第l个传输层传输的参考信号做预编码，该N_l个预编码向量例如记作

终端设备基于第l个传输层上接收到的预编码参考信号做信道测量而反馈的各预编码向量的权重分别为

For example, the network device may base the

The N _l precoding vectors precode the reference signal transmitted through the lth transport layer, and the N _l precoding vectors are, for example, denoted as

The weights of each precoding vector fed back by the terminal device based on the precoding reference signal received on the lth transport layer for channel measurement are:

这N_z个预编码向量对通过第z个传输层传输的参考信号做预编码，该N_z个预编码向量例如记作

终端设备基于第l个传输层上接收到的预编码参考信号做信道测量而反馈的各预编码向量的权重分别为

At the same time, the network device may, based on the

The _Nz precoding vectors precode the reference signal transmitted through the _zth transport layer, and the Nz precoding vectors are, for example, denoted as

The weights of each precoding vector fed back by the terminal device based on the precoding reference signal received on the lth transport layer for channel measurement are:

The values of N _l and N _z may be the same or different. This application does not limit this.

After receiving the weights of each precoding vector fed back by the terminal device based on the lth transport layer and the zth transport layer, the network device may determine the weighted sum of the precoding vectors determined based on the different transport layers, and then determine the next time Precoding is performed on the reference signals transmitted by the lth transport layer and the zth transport layer. The specific method for the network device to determine the precoding vector and precoding the reference signal based on each transport layer in the plurality of transport layers is the same as the above-mentioned determination and precoding vector for the lth transport layer and precoding the reference signal. The specific methods are the same, and are not repeated here for brevity.

In addition, the precoding reference signals respectively transmitted by the network device through the lth transmission layer and the zth transmission layer may be precoding reference signals sent to the same terminal device, or may be precoding reference signals sent to different terminal devices. . This application does not limit this.

Optionally, the method further includes: Step 250, the terminal device sends a precoding vector set reset indication, where the precoding vector set reset indication is used to instruct to perform channel measurement based on the reset precoding vector set. Correspondingly, in step 260, the network device receives the precoding vector set reset indication.

In some cases, such as when the end device is moving rapidly, the channel may suddenly change. At this time, if the channel measurement is still performed based on the previously determined precoding vector set, accurate feedback from the terminal device may not be obtained. The terminal device may determine whether to reset the precoding vector set according to its own movement or the difference and change between the two measurement results. The terminal device may suggest to the network device to update the precoding vector set by sending a precoding vector set reset indication to the network device. However, it should be understood that whether the network device updates the precoding vector set does not entirely depend on the precoding vector set reset instruction sent by the terminal device. The network device may also comprehensively consider whether to update the precoding vector set based on more factors.

In step 260, the network device determines a target precoding vector for data transmission according to the feedback information received at the Kth time; and precodes the downlink data based on the target precoding vector to obtain precoded data.

In this embodiment of the present application, the target precoding vector used for data transmission may be a precoding vector corresponding to the transport layer. That is, the precoding vector used to precode data when transmitting data through a certain transport layer. For example, the precoding vector used to precode data when data is transmitted through the lth transport layer.

b_(K-1)(N-1)+2，b_(K-1)(N-1)+3，……，b_K(N-1)+1对通过第l个传输层第K次发送的参考信号做预编码，终端设备第K次反馈的各预编码向量的权重分别为

则可以确定用于对第l个传输层上的数据做预编码的目标预编码向量

其中，

表示基于上一次(即，第K-1次)反馈确定的预编码向量的加权和，

表示在第K次接收到的反馈信息中所指示的

的权重。If the network device transmits downlink data through the lth transport layer, the network device may determine the target precoding vector according to the feedback information received at the Kth time. Suppose the network device passes N precoding vectors

b _(K-1)(N-1)+2 , b _(K-1)(N-1)+3 , ..., b _K(N-1)+1 pairs pass through the lth transport layer for the Kth time The transmitted reference signal is precoded, and the weights of each precoding vector fed back by the terminal equipment for the Kth time are:

Then the target precoding vector for precoding the data on the lth transport layer can be determined

in,

represents the weighted sum of the precoding vectors determined based on the previous (that is, the K-1th) feedback,

Indicates the information indicated in the feedback information received at the Kth time

the weight of.

It should be understood that the precoding vectors and their weights listed above are only examples, and should not constitute any limitation to the present application. It should also be understood that the network device is not limited to sending downlink data to the same terminal device through one transport layer. When the network device sends downlink data to the same terminal device through multiple transport layers, it may precode the data transmitted on the corresponding transport layer based on the target precoding vector corresponding to each transport layer.

It should also be understood that, in the embodiments of the present application, K≧1. The target precoding vector enumerated above shows an example of the target precoding vector determined based on multiple feedbacks from the terminal device, that is, an example where K>1. The network device may also determine the target precoding vector for data transmission based on a feedback from the terminal device.

则可以确定用于对第l个传输层上的数据做预编码的目标预编码向量

For example, if N precoding vectors are used to precode reference signals transmitted through one or more transport layers, and the N precoding vectors b ₁ , b ₂ , . . . fed back for the lth transport layer, The weights of b _N feedback are

Then the target precoding vector for precoding the data on the lth transport layer can be determined

反馈的权重分别为

则可以确定通过该传输层传输数据时用于对数据做预编码的目标预编码向量

若N₂个预编码向量用于对通过另一个传输层(如第2个传输层，即l＝2)传输的参考信号做预编码，且该N₂个预编码向量反馈的权重分别为

则可以确定通过该传输层传输数据时用于对数据做预编码的目标预编码向量

由此可以得到，若通过N_l个预编码向量对第l个传输层上传输的参考信号做预编码，且针对该N_l个预编码向量

反馈的权重分别为

则通过该第l个传输层传输数据时用于对数据做预编码的目标预编码向量

其中N_l为正整数。For another example, if N ₁ precoding vectors are used for precoding a reference signal transmitted through one transport layer (eg, the first transport layer, ie, l=1), and the N ₁ precoding vectors are used for precoding

The feedback weights are

Then the target precoding vector used for precoding the data can be determined when the data is transmitted through the transport layer

If the N ₂ precoding vectors are used to precode the reference signal transmitted through another transmission layer (such as the second transmission layer, that is, l=2), and the feedback weights of the N ₂ precoding vectors are respectively

Then the target precoding vector used for precoding the data can be determined when the data is transmitted through the transport layer

It can be obtained from this that if the reference signal transmitted on the _lth transmission layer is precoded by N1 precoding vectors _, and the N1 precoding vectors are used for precoding

The feedback weights are

Then the target precoding vector used for precoding the data when transmitting the data through the lth transport layer

where N _l is a positive integer.

Optionally, J of the L transport layers are used to transmit data with the terminal device. The J transport layers may include, for example, the above-mentioned lth transport layer and J-1 transport layers other than the lth transport layer. J≤Z and J is a positive integer.

That is, the network device may send data to the same terminal device through some or all of the L transport layers. For example, if the number of transmission layers used to transmit data is J, the target precoding vector used for precoding data on any one of the J transmission layers can be determined by the method described above.

个预编码向量的权重。该

个预编码向量是用于对通过第j个传输层第k次发送的参考信号做预编码的预编码向量，或者说，用于生成通过第j个传输层第k次发送的预编码参考信号的预编码向量。该

个预编码向量的加权和为

个预编码向量中的一个预编码向量。该

个预编码向量是用于对通过第j个传输层第k+1次发送的参考信号做预编码的预编码向量，或者说，用于生成通过第j个传输层第k+1次发送的预编码参考信号的预编码向量。其中，1≤j≤J-1，j可以在1至J-1中任意取值。Optionally, the method further includes: the network device determines, based on the feedback information received K times, a target precoding vector used for transmitting data at the jth transport layer. The j-th transport layer is any one of the J-1 transport layers except the j-th transport layer in the above-mentioned J transport layers. The feedback information received at the kth time among the feedback information received at the K times is used to indicate

The weights of the precoding vectors. Should

The precoding vectors are the precoding vectors used to precode the reference signal transmitted by the jth transport layer at the kth time, or, in other words, used to generate the precoding reference signal transmitted by the jth transport layer at the kth time the precoding vector. Should

The weighted sum of the precoding vectors is

one of the precoding vectors. Should

The precoding vectors are the precoding vectors used to precode the reference signal transmitted through the jth transport layer at the k+1th time, or, in other words, used to generate the k+1th transmission through the jth transport layer. The precoding vector for the precoding reference signal. Among them, 1≤j≤J-1, and j can take any value from 1 to J-1.

That is to say, when a network device sends a precoding reference signal to the same terminal device through multiple transmission layers, the terminal device can feed back each precoding reference signal corresponding to the precoding reference signal transmitted through each transmission layer through the same feedback information. The weights of the encoded vector. It is only that the precoding vectors corresponding to the precoding reference signals transmitted through different transport layers may be different, and the number of the corresponding precoding vectors may also be different. For the convenience of distinction, the superscripts (j) and (l) are used to distinguish different transport layers among the M transport layers.

It should be noted that the number of transport layers measured during channel measurement by the network device is not equal to the number of transport layers used for data transmission. The network device may schedule some or all of the transmission layers according to the number of transmission layers determined by the channel measurement, so as to transmit data.

Since the target precoding vector is a precoding vector corresponding to one transport layer. The target precoding vector can be used to precode data transmitted over the transport layer. When the network device transmits data through multiple transport layers, the network device may determine target precoding vectors corresponding to the multiple transport layers respectively, and the network device may pair the data transmitted through the transport layer based on the precoding vectors corresponding to each transport layer. The data is precoded to obtain precoded data. Alternatively, the network device may also determine a precoding matrix according to target precoding vectors corresponding to multiple transmission layers, so as to perform precoding on the data to be transmitted, and then obtain the precoded data.

For example, the network device can separately precode the reference signals of each transport layer based on different precoding vectors, and the terminal device can also separately perform channel measurement based on the precoding reference signals received on different transport layers, and then determine the relationship with each transport layer. The weight of each precoding vector corresponding to the transport layer. The network device may also determine the target precoding vector corresponding to each transport layer based on the weight of each precoding vector fed back by the terminal device for each transport layer. For example p ⁽¹⁾ and p ⁽²⁾ shown above.

For another example, the network device may precode the reference signal based on multiple precoding vectors, and the terminal device may also perform channel measurement based on the received precoding reference signal, thereby determining the weight of each precoding vector. As described above, the terminal device may determine the number of transmission layers according to the channel matrix, and then determine the observation value based on the observation matrix corresponding to the number of transmission layers, and then determine the weights of each precoding vector in different transmission layers. The network device may determine a target precoding vector corresponding to each transport layer, such as p _l shown above, based on the weight of each precoding vector fed back by the terminal device for each transport layer. The network device may also construct a precoding matrix based on the weight of each precoding vector fed back by the terminal device for each transport layer, for example, constructing a precoding matrix from p ₁ to p _L.

The specific manner in which the network device determines the target precoding vector based on the feedback information sent by the terminal device is not limited to those listed above. This application does not limit the specific manner in which the network device determines the target precoding vector.

In step 270, the network device sends the precoded data. Correspondingly, in step 270, the terminal device receives the precoded data.

It should be understood that the specific process of sending the precoded data by the network device through physical downlink resources, such as a physical downlink shared channel (PDSCH), may be the same as that in the prior art. For the sake of brevity, details are not repeated here.

It should also be understood that the specific process of the channel measurement method 200 provided by the present application is described in detail above with reference to FIG. 2 . However, this should not constitute any limitation to this application. FIG. 2 is only an example, and shows the flow of sending downlink data after the operations of steps 210 to 240 are repeatedly performed K times. However, it should be understood that the K times are only examples, and should not constitute any limitation to the present application. This application does not limit the timing for the network device to send downlink data. In other words, the present application does not limit the order of execution of steps 210 to 240 and steps 260 to 270 .

Based on the above technical solutions, the terminal device can perform channel measurement and feedback based on the precoding reference signals sent by the network device multiple times. The precoding vector used by the precoding reference signal sent by the network device each time refers to the information fed back by the previous terminal device, so it can get closer and closer to the direction of the terminal device, so that the obtained feedback from the terminal device is more accurate. In addition, the network device may determine the precoding vector used to precode the data based on the latest feedback from the terminal device, and the precoding vector thus determined may be considered to be the closest to the direction of the terminal device in the currently obtained channel measurement results. The precoding vector is therefore beneficial to improve data transmission performance.

In the above, the method provided by the embodiment of the present application is described in detail with reference to FIG. 2 . Hereinafter, the device provided by the embodiment of the present application will be described in detail with reference to FIG. 3 to FIG. 5 .

FIG. 3 is a schematic block diagram of a communication apparatus provided by an embodiment of the present application. As shown in FIG. 3 , the communication apparatus 1000 may include a processing unit 1100 and a transceiver unit 1200 .

In a possible design, the communication apparatus 1000 may correspond to the terminal device in the above method embodiments, for example, may be a terminal device or a chip configured in the terminal device.

Specifically, the communication apparatus 1000 may correspond to the terminal device in the method 200 according to the embodiment of the present application, and the communication apparatus 1000 may include a unit for executing the method performed by the terminal device in the method 200 in FIG. 2 . Moreover, each unit in the communication apparatus 1000 and the other operations and/or functions mentioned above are respectively to implement the corresponding flow of the method 200 in FIG. 2 .

Wherein, when the communication device 1000 is used to execute the method 200 in FIG. 2 , the processing unit 1100 can be used to execute the step 220 of the method 200 , and the transceiver unit 1200 can be used to execute the steps 210 , 230 , 250 and 250 of the method 200 . Step 270. It should be understood that the specific process of each unit performing the above-mentioned corresponding steps has been described in detail in the above-mentioned method embodiments, and for the sake of brevity, it will not be repeated here.

It should also be understood that when the communication device 1000 is a terminal device, the transceiver unit 1200 in the communication device 1000 may correspond to the transceiver 2020 in the terminal device 2000 shown in FIG. 4 , and the processing unit 1100 in the communication device 1000 may Corresponds to the processor 2010 in the terminal device 2000 shown in FIG. 4 .

It should also be understood that when the communication apparatus 1000 is a chip configured in a terminal device, the transceiver unit 1200 in the communication apparatus 1000 may be an input/output interface.

In another possible design, the communication apparatus 1000 may correspond to the network device in the above method embodiments, for example, may be a network device or a chip configured in the network device.

Specifically, the communication apparatus 1000 may correspond to the network device in the method 200 according to the embodiment of the present application, and the communication apparatus 1000 may include a unit for executing the method performed by the network device in the method 200 in FIG. 2 . Moreover, each unit in the communication apparatus 1000 and the other operations and/or functions mentioned above are respectively to implement the corresponding flow of the method 200 in FIG. 2 .

Wherein, when the communication device 1000 is used to execute the method 200 in FIG. 4 , the processing unit 1100 can be used to execute steps 240 and 260 in the method 200 , and the transceiver unit 1200 can be used to execute steps 210 , 230 , Step 250 and Step 270. It should be understood that the specific process of each unit performing the above-mentioned corresponding steps has been described in detail in the above-mentioned method embodiments, and for the sake of brevity, it will not be repeated here.

It should also be understood that when the communication device 1000 is a network device, the transceiver unit in the communication device 1000 may correspond to the transceiver 3200 in the network device 3000 shown in FIG. 5 , and the processing unit 1100 in the communication device 1000 may Corresponds to the processor 3100 in the network device 3000 shown in FIG. 5 .

It should also be understood that when the communication apparatus 1000 is a chip configured in a network device, the transceiver unit 1200 in the communication apparatus 1000 may be an input/output interface.

FIG. 4 is a schematic structural diagram of a terminal device 2000 provided by an embodiment of the present application. The terminal device 2000 can be applied to the system shown in FIG. 1 to perform the functions of the terminal device in the foregoing method embodiments. As shown in the figure, the terminal device 2000 includes a processor 2010 and a transceiver 2020 . Optionally, the terminal device 2000 further includes a memory 2030 . Among them, the processor 2010, the transceiver 2002 and the memory 2030 can communicate with each other through an internal connection path to transmit control and/or data signals. The computer program is called and executed to control the transceiver 2020 to send and receive signals. Optionally, the terminal device 2000 may further include an antenna 2040 for sending the uplink data or uplink control signaling output by the transceiver 2020 through wireless signals.

The above-mentioned processor 2010 and the memory 2030 can be combined into a processing device, and the processor 2010 is configured to execute the program codes stored in the memory 2030 to realize the above-mentioned functions. During specific implementation, the memory 2030 may also be integrated in the processor 2010 or independent of the processor 2010 . The processor 2010 may correspond to the processing unit in FIG. 3 .

The foregoing transceiver 2020 may correspond to the transceiver unit in FIG. 3 , and may also be referred to as a transceiver unit. The transceiver 2020 may include a receiver (or receiver, receiving circuit) and a transmitter (or transmitter, transmitting circuit). Among them, the receiver is used for receiving signals, and the transmitter is used for transmitting signals.

It should be understood that the terminal device 2000 shown in FIG. 4 can implement various processes involving the terminal device in the method embodiment shown in FIG. 2 . The operations and/or functions of each module in the terminal device 2000 are respectively to implement the corresponding processes in the foregoing method embodiments. For details, reference may be made to the descriptions in the foregoing method embodiments, and to avoid repetition, the detailed descriptions are appropriately omitted here.

The above-mentioned processor 2010 may be used to perform the actions described in the foregoing method embodiments that are implemented inside the terminal device, and the transceiver 2020 may be used to perform the actions described in the foregoing method embodiments that the terminal device sends to or receives from the network device. action. For details, please refer to the descriptions in the foregoing method embodiments, which will not be repeated here.

Optionally, the above terminal device 2000 may further include a power supply 2050 for providing power to various devices or circuits in the terminal device.

In addition, in order to make the functions of the terminal device more complete, the terminal device 2000 may further include one or more of an input unit 2060, a display unit 2070, an audio circuit 2080, a camera 2090, a sensor 2100, etc., the audio circuit Speakers 2082, microphones 2084, etc. may also be included.

FIG. 5 is a schematic structural diagram of a network device provided by an embodiment of the present application, which may be, for example, a schematic structural diagram of a base station. The base station 3000 can be applied to the system shown in FIG. 1 to perform the functions of the network device in the foregoing method embodiments. As shown, the base station 3000 may include one or more radio frequency units, such as a remote radio unit (RRU) 3100 and one or more baseband units (BBUs) (also referred to as distributed units (DUs) )) 3200. The RRU 3100 may be called a transceiver unit, which corresponds to the transceiver unit 1100 in FIG. 3 . Optionally, the transceiver unit 3100 may also be referred to as a transceiver, a transceiver circuit, or a transceiver, etc., which may include at least one antenna 3101 and a radio frequency unit 3102 . Optionally, the transceiver unit 3100 may include a receiving unit and a sending unit, the receiving unit may correspond to a receiver (or called a receiver, a receiving circuit), and the sending unit may correspond to a transmitter (or called a transmitter, a sending circuit). The part of the RRU 3100 is mainly used for sending and receiving radio frequency signals and converting radio frequency signals to baseband signals, for example, for sending indication information to terminal equipment. The part of the BBU 3200 is mainly used to perform baseband processing, control the base station, and so on. The RRU 3100 and the BBU 3200 may be physically set together or physically separated, that is, a distributed base station.

The BBU 3200 is the control center of the base station, and can also be called a processing unit, which can correspond to the processing unit 1200 in FIG. For example, the BBU (processing unit) may be used to control the base station to perform the operation procedure of the network device in the foregoing method embodiments, for example, to generate the foregoing indication information and the like.

In an example, the BBU 3200 may be composed of one or more boards, and the multiple boards may jointly support a wireless access network (such as an LTE network) of a single access standard, or may respectively support a wireless access network of different access standards. Wireless access network (such as LTE network, 5G network or other network). The BBU 3200 also includes a memory 3201 and a processor 3202. The memory 3201 is used to store necessary instructions and data. The processor 3202 is configured to control the base station to perform necessary actions, for example, to control the base station to perform the operation flow of the network device in the foregoing method embodiments. The memory 3201 and processor 3202 may serve one or more single boards. That is to say, the memory and processor can be provided separately on each single board. It can also be that multiple boards share the same memory and processor. In addition, necessary circuits may also be provided on each single board.

It should be understood that the base station 3000 shown in FIG. 5 can implement various processes involving network devices in the method embodiment shown in FIG. 2 . The operations and/or functions of each module in the base station 3000 are respectively to implement the corresponding processes in the foregoing method embodiments. For details, reference may be made to the descriptions in the foregoing method embodiments, and to avoid repetition, the detailed descriptions are appropriately omitted here.

The above-mentioned BBU 3200 may be used to perform the actions implemented by the network device described in the foregoing method embodiments, and the RRU 3100 may be used to perform the actions that the network device sends to or receives from the terminal device described in the foregoing method embodiments. For details, please refer to the descriptions in the foregoing method embodiments, which will not be repeated here.

It should be understood that the base station 3000 shown in FIG. 5 is only a possible architecture of a network device, and should not constitute any limitation to the present application. The methods provided in this application may be applicable to network devices of other architectures. For example, network equipment including CU, DU and active antenna unit (active antenna unit, AAU), etc. This application does not limit the specific architecture of the network device.

An embodiment of the present application further provides a processing apparatus, including a processor and an interface, where the processor is configured to execute the method in any of the foregoing method embodiments.

It should be understood that the above-mentioned processing device may be one or more chips. For example, the processing device may be a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on chip (SoC), or a The central processing unit (CPU) may also be a network processor (NP), a digital signal processing circuit (digital signal processor, DSP), or a microcontroller (micro controller unit, MCU). ), it can also be a programmable logic device (PLD) or other integrated chips.

In the implementation process, each step of the above-mentioned method can be completed by a hardware integrated logic circuit in a processor or an instruction in the form of software. The steps of the methods disclosed in conjunction with the embodiments of the present application may be directly embodied as executed by a hardware processor, or executed by a combination of hardware and software modules in the processor. The software modules may be located in random access memory, flash memory, read-only memory, programmable read-only memory or electrically erasable programmable memory, registers and other storage media mature in the art. The storage medium is located in the memory, and the processor reads the information in the memory, and completes the steps of the above method in combination with its hardware. To avoid repetition, detailed description is omitted here.

It should be noted that the processor in this embodiment of the present application may be an integrated circuit chip, which has a signal processing capability. In the implementation process, each step of the above method embodiments may be completed by a hardware integrated logic circuit in a processor or an instruction in the form of software. The aforementioned processors may be general purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components . The methods, steps, and logic block diagrams disclosed in the embodiments of this application can be implemented or executed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in conjunction with the embodiments of the present application may be directly embodied as executed by a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules may be located in random access memory, flash memory, read-only memory, programmable read-only memory or electrically erasable programmable memory, registers and other storage media mature in the art. The storage medium is located in the memory, and the processor reads the information in the memory, and completes the steps of the above method in combination with its hardware.

It can be understood that the memory in this embodiment of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically programmable Erase programmable read-only memory (electrically EPROM, EEPROM) or flash memory. Volatile memory may be random access memory (RAM), which acts as an external cache. By way of example and not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous DRAM, SDRAM), double data rate synchronous dynamic random access memory (double data rate SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (enhanced SDRAM, ESDRAM), synchronous link dynamic random access memory (synchlink DRAM, SLDRAM) And direct memory bus random access memory (direct rambus RAM, DR RAM). It should be noted that the memory of the systems and methods described herein is intended to include, but not be limited to, these and any other suitable types of memory.

According to the method provided by the embodiment of the present application, the present application also provides a computer program product, the computer program product includes: computer program code, when the computer program code is run on a computer, the computer is made to execute the embodiment shown in FIG. 2 . method in .

According to the method provided by the embodiment of the present application, the present application further provides a computer-readable medium, where the computer-readable medium stores program codes, when the program codes are executed on a computer, the computer is made to execute the embodiment shown in FIG. 2 . method in .

According to the method provided by the embodiment of the present application, the present application further provides a system, which includes the aforementioned one or more terminal devices and one or more network devices.

The network equipment in each of the above apparatus embodiments completely corresponds to the terminal equipment and the network equipment or terminal equipment in the method embodiments, and corresponding steps are performed by corresponding modules or units. For the sending step, other steps except sending and receiving may be performed by a processing unit (processor). For functions of specific units, reference may be made to corresponding method embodiments. The number of processors may be one or more.

The terms "component", "module", "system" and the like are used in this specification to refer to a computer-related entity, hardware, firmware, a combination of hardware and software, software, or software in execution. For example, a component may be, but is not limited to, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, and/or a computer. By way of illustration, both an application running on a computing device and the computing device may be components. One or more components may reside within a process and/or thread of execution, and a component may be localized on one computer and/or distributed between 2 or more computers. In addition, these components can execute from various computer readable media having various data structures stored thereon. A component may, for example, be based on a signal having one or more data packets (eg, data from two components interacting with another component between a local system, a distributed system, and/or a network, such as the Internet interacting with other systems via signals) Communicate through local and/or remote processes.

Those of ordinary skill in the art will appreciate that the various illustrative logical blocks and steps described in connection with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware accomplish. 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.

In the above embodiments, the functions of each functional unit may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions (programs). When the computer program instructions (programs) are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are generated. The computer may be a general purpose computer, special purpose computer, computer network, or other programmable device. The computer instructions may be stored in or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions may be downloaded from a website site, computer, server or data center Transmission to another website site, computer, server, or data center by wire (eg, coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (eg, infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that includes an integration of one or more available media. The available media may be magnetic media (eg, floppy disks, hard disks, magnetic tapes), optical media (eg, high-density digital video discs (DVDs)), or semiconductor media (eg, solid state disks, SSD)) etc.

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, removable hard disk, read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk and other media that can store program codes .

The above are only specific embodiments of the present application, but the protection scope of the present application is not limited to this. should be covered within the scope of protection of this application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims (24)

1. A method of channel measurement, comprising:

determining a target precoding vector for data transmission based on the K times of received feedback information; the K times of received feedback information are determined based on K times of transmitted precoding reference signals, wherein the K-th time of received feedback information is used for indicating N_kWeight of precoding vectors, N_kThe weighted sum of precoding vectors is N_k+1One of the precoding vectors; said N is_kEach precoding vector is used for generating a precoding reference signal sent at the kth time, and N is_k+1The precoding vectors are used for generating precoding reference signals sent for the (k + 1) th time; k is more than or equal to 1, K is more than or equal to 1 and less than or equal to K, and K, K and N_kAnd N_k+1Are all positive integers;

pre-coding data to be transmitted according to the target pre-coding vector to obtain pre-coded data;

and transmitting the pre-coded data.

2. The method of claim 1, wherein said N is_k+1The remaining N of the precoding vectors_k+1-1 precoding vector is a precoding vector of a predetermined set of precoding vectors.

3. The method of claim 1, wherein the method further comprises:

generating a first precoding vector set based on the I-th received feedback information in the K received feedback information, wherein the I-th received feedback information is used for indicating N_IWeight of precoding vectors, N_IThe precoding vectors are used for generating precoding reference signals sent for the I time; the first set of precoding vectors comprises N_IWeighted sum of precoding vectors and their weight determination

And based on

A plurality of vectors constructed; i is more than or equal to 1 and less than or equal to K, and I is a positive integer.

4. The method of claim 3, wherein the precoding vector used to generate the precoded reference signal for the I +1 th transmission is a precoding vector in the first set of precoding vectors; at least part of precoding vectors used for generating the precoding reference signals of the previous I times of transmission are vectors in a second predetermined precoding vector set; the second set of precoding vectors is different from the first set of precoding vectors.

5. The method of claim 3 or 4, wherein the first set of precoding vectors comprises at least T precoding vectors; and

generating a first precoding vector set based on the ith received feedback information in the K received feedback information, including:

determining the N based on the I-th received feedback information in the K received feedback information_IWeighted sum of precoding vectors

A precoding vector in the first set of precoding vectors;

based on

Generating T-1 Givens rotation matrixes G (c, T, theta) or G (T, c, theta) in a row where the element b with the maximum medium amplitude is located; wherein c represents b in

C is a positive integer, and c is more than or equal to 1 and less than or equal to T; t is an integer value from 1 to T, T is not equal to c, and theta represents a rotation angle;

generating remaining T-1 vectors of the first set of precoding vectors based on the T-1 Givens rotation matrices G (c, T, θ) or G (T, c, θ).

6. The method according to any of claims 1 to 4, wherein the K times of received feedback information are used to determine a precoding vector used for transmitting the data through the L-th transmission layer of the L transmission layers; one or more transmission layers in the L transmission layers are used for transmitting the data, L is more than or equal to 1 and less than or equal to L, L is more than or equal to 1, and L and L are integers.

7. The method of claim 6, wherein J transport layers of the L transport layers are used for transmitting data, the J transport layers including the L-th transport layer and J-1 transport layers other than the L-th transport layer, J ≦ 2 ≦ L, J being an integer;

the method further comprises the following steps:

determining a precoding vector used for transmitting data on a jth transmission layer based on the feedback information received K times, wherein the jth transmission layer is any one of the J-1 transmission layers; the feedback information received for the K times is determined by precoding reference signals sent on the jth transmission layer for the K times; the feedback information received at the K time in the feedback information received at the K time is used for indicating

A weight of a precoding vector, the

A weighted sum of precoding vectors of

One of the precoding vectors; the above-mentioned

Each precoding vector is used for generating a precoding reference signal sent by the jth transmission layer for the kth time

The precoding vectors are used for generating precoding reference signals sent by the jth transmission layer for the (k + 1) th time; j is more than or equal to 1 and less than or equal to J-1, and J is an integer.

8. The method of any of claims 1-4, 7, further comprising:

receiving a precoding vector set reset indication which is used for indicating that channel measurement is carried out based on the reset precoding vector set.

9. A method of channel measurement, comprising:

generating feedback information based on the received precoding reference signal, the feedback information indicating weights of one or more precoding vectors, the one or more precoding vectors being precoding vectors used to generate the precoding reference signal;

and sending the feedback information.

10. The method of claim 9, wherein the generating feedback information based on the received precoded reference signal comprises:

determining weights of the one or more precoding vectors based on a predetermined observation matrix W and the received precoding reference signals; wherein, W is S (U Λ)^-1(ii) a U and Λ are matrixes obtained by singular value decomposition of a channel matrix H; u is an R-dimensional unitary matrix, and Λ is an R row and T column diagonal matrix; s is a matrix of Z rows and R columns, each row in S comprises R-1 zero elements, and the Z-th element in the Z-th row in S is 1; z is more than or equal to 1 and less than or equal to Z, Z represents the rank of a channel matrix H, R represents the number of receiving antennas, and Z, Z, T and R are integers;

generating the feedback information based on weights of the one or more precoding vectors.

11. The method of claim 9 or 10, wherein the method further comprises:

and sending a precoding vector set resetting indication, wherein the precoding vector set resetting indication is used for indicating that channel measurement is carried out based on the reset precoding vector set.

12. A communications apparatus, comprising:

a processing unit for determining for data transmission based on the K received feedback informationA target precoding vector; the K times of received feedback information are determined based on K times of transmitted precoding reference signals, wherein the K-th time of received feedback information is used for indicating N_kWeight of precoding vectors, N_kThe weighted sum of precoding vectors is N_k+1One of the precoding vectors; said N is_kEach precoding vector is used for generating a precoding reference signal sent at the kth time, and N is_k+1The precoding vectors are used for generating precoding reference signals sent for the (k + 1) th time; k is more than or equal to 1, K is more than or equal to 1 and less than or equal to K, and K, K and N_kAnd N_k+1Are all positive integers; the processing unit is further configured to precode data to be transmitted according to the target precoding vector to obtain precoded data;

and the receiving and sending unit is used for sending the precoded data.

13. The apparatus of claim 12, wherein N is the number of bits in the set of bits_k+1The remaining N of the precoding vectors_k+1-1 precoding vector is a precoding vector of a predetermined set of precoding vectors.

14. The apparatus of claim 12, wherein the processing unit is further for generating a first set of precoding vectors based on an I-th received feedback information of the K received feedback information, the I-th received feedback information indicating N_IWeight of precoding vectors, N_IThe precoding vectors are used for generating precoding reference signals sent for the I time; the first set of precoding vectors comprises N_IWeighted sum of precoding vectors and their weight determination

And based on

A plurality of vectors constructed; 1 is less than or equal toI is less than or equal to K and is a positive integer.

15. The apparatus of claim 14, wherein a precoding vector used to generate the I +1 th transmitted precoded reference signal is a precoding vector in the first set of precoding vectors; at least part of precoding vectors used for generating the precoding reference signals of the previous I times of transmission are vectors in a second predetermined precoding vector set; the second set of precoding vectors is different from the first set of precoding vectors.

16. The apparatus of claim 14 or 15, wherein the first set of precoding vectors comprises at least T precoding vectors,

the processing unit is specifically configured to:

determining the N based on the I-th received feedback information in the K received feedback information_IWeighted sum of precoding vectors

A precoding vector in the first set of precoding vectors;

based on

Generating T-1 Givens rotation matrixes G (c, T, theta) or G (T, c, theta) in a row where the element b with the maximum medium amplitude is located; wherein c represents b in

C is a positive integer, and c is more than or equal to 1 and less than or equal to T; t is an integer value from 1 to T, T is not equal to c, and theta represents a rotation angle;

generating remaining T-1 vectors of the first set of precoding vectors based on the T-1 Givens rotation matrices G (c, T, θ) or G (T, c, θ).

17. The apparatus according to any of claims 12 to 15, wherein the K times received feedback information is used to determine a precoding vector used for transmitting the data through the ith transmission layer of L transmission layers; one or more transmission layers in the L transmission layers are used for transmitting the data, L is more than or equal to 1 and less than or equal to L, L is more than or equal to 1, and L and L are integers.

18. The apparatus of claim 17, wherein J transport layers of the L transport layers are used for transmitting data, the J transport layers including the L-th transport layer and J-1 transport layers other than the L-th transport layer, J ≦ 2 ≦ L, J being an integer;

the processing unit is further to:

determining a precoding vector used for transmitting data on a jth transmission layer based on the feedback information received K times, wherein the jth transmission layer is any one of the J-1 transmission layers; the feedback information received for the K times is determined by precoding reference signals sent on the jth transmission layer for the K times; the feedback information received at the K time in the feedback information received at the K time is used for indicating

A weight of a precoding vector, the

A weighted sum of precoding vectors of

One of the precoding vectors; the above-mentioned

The precoding vectors are used for generating precoding reference signals sent by the jth transmission layer at the kth timeSaid

The precoding vectors are used for generating precoding reference signals sent by the jth transmission layer for the (k + 1) th time; j is more than or equal to 1 and less than or equal to J-1, and J is an integer.

19. The apparatus according to any of claims 12 to 15, 18, wherein the transceiver unit is further configured to

Receiving a precoding vector set reset indication which is used for indicating that channel measurement is carried out based on the reset precoding vector set.

20. A communications apparatus, comprising:

a processing unit, configured to generate feedback information based on the received precoding reference signal, where the feedback information is used to indicate weights of one or more precoding vectors, and the one or more precoding vectors are precoding vectors used to generate the precoding reference signal;

and the transceiving unit is used for sending the feedback information.

21. The apparatus as recited in claim 20, said processing unit to:

determining weights of the one or more precoding vectors based on a predetermined observation matrix W and the received precoding reference signals; wherein, W is S (U Λ)^-1(ii) a U and Λ are matrixes obtained by singular value decomposition of a channel matrix H; u is an R-dimensional unitary matrix, and Λ is an R row and T column diagonal matrix; s is a matrix of Z rows and R columns, each row in S comprises R-1 zero elements, and the Z-th element in the Z-th row in S is 1; z is more than or equal to 1 and less than or equal to Z, Z represents the rank of the channel moment H, R represents the number of receiving antennas, and Z, Z, T and R are integers;

generating the feedback information based on weights of the one or more precoding vectors.

22. The apparatus of claim 20 or 21, wherein the transceiver unit is further configured to send a precoding vector set reset indication, the precoding vector set reset indication indicating that channel measurements are to be performed based on the reset precoding vector set.

23. A communications apparatus comprising at least one processor configured to perform the method of any of claims 1-11.

24. A computer-readable medium, comprising a computer program which, when run on a computer, causes the computer to perform the method of any one of claims 1 to 11.

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