WO2021081847A1 - 一种信道测量方法和通信装置 - Google Patents

一种信道测量方法和通信装置 Download PDF

Info

Publication number
WO2021081847A1
WO2021081847A1 PCT/CN2019/114491 CN2019114491W WO2021081847A1 WO 2021081847 A1 WO2021081847 A1 WO 2021081847A1 CN 2019114491 W CN2019114491 W CN 2019114491W WO 2021081847 A1 WO2021081847 A1 WO 2021081847A1
Authority
WO
WIPO (PCT)
Prior art keywords
delay
port
vector
ports
reference signal
Prior art date
Application number
PCT/CN2019/114491
Other languages
English (en)
French (fr)
Inventor
刘永
葛士斌
金黄平
毕晓艳
Original Assignee
华为技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 华为技术有限公司 filed Critical 华为技术有限公司
Priority to CN201980101549.0A priority Critical patent/CN114600384B/zh
Priority to PCT/CN2019/114491 priority patent/WO2021081847A1/zh
Publication of WO2021081847A1 publication Critical patent/WO2021081847A1/zh

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/32—Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
    • H04L27/34—Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
    • H04W52/04—TPC
    • H04W52/18—TPC being performed according to specific parameters
    • H04W52/24—TPC being performed according to specific parameters using SIR [Signal to Interference Ratio] or other wireless path parameters

Definitions

  • This application relates to the field of wireless communication, and more specifically, to a channel measurement method and communication device.
  • massive multiple-input multiple-output massive MIMO
  • network equipment can reduce the interference between multiple users and the interference between multiple signal streams of the same user through precoding. Conducive to improving signal quality, realizing space division multiplexing, and improving spectrum utilization.
  • the terminal device may determine the precoding matrix based on downlink channel measurement, and hopes to enable the network device to obtain a precoding matrix that is the same or similar to the precoding matrix determined by the terminal device through feedback.
  • the terminal device may, for example, instruct to construct the precoding matrix by feeding back one or more spatial vectors, one or more frequency domain vectors, and one or more weighting coefficients.
  • this feedback method brings a large feedback overhead.
  • TDD time division duplexing
  • FDD frequency division duplexing
  • the present application provides a channel measurement method and communication device, in order to utilize partial reciprocity between uplink and downlink channels to obtain channel state information (CSI) of the downlink channel and improve system transmission performance.
  • CSI channel state information
  • a channel measurement method is provided.
  • the method may be executed by a terminal device, or may also be executed by a component (such as a chip or a chip system, etc.) configured in the terminal device.
  • the method includes: generating first indication information for indicating P groups of weighting coefficients corresponding to P transmission ports, and the reference signal of each transmission port in the P transmission ports is based on a delay vector And/or an angle vector is obtained by precoding the reference signal, and the weighting coefficient corresponding to each transmission port in the P transmission ports and the delay vector and/or angle vector corresponding to each transmission port are used to construct the precoding matrix; Among them, the p-th group of weighting coefficients corresponding to the p-th transmitting port among the P-th transmitting ports are obtained by time-domain transforming the channel information between the p-th transmitting port and the R receiving ports of the terminal device. Each transmitting port is any one of the P transmitting ports, 0 ⁇ p ⁇ P-1, P ⁇ 1, R ⁇ 1, p, P, and R are all integers; sending the first indication information.
  • the above-mentioned reference signal may be obtained by precoding based on one of the angle vector and the delay vector, or may be obtained by precoding based on the angle vector and the delay vector.
  • the terminal device can perform channel measurement based on the received reference signal to feed back the weighting coefficient corresponding to each transmission port. It can be understood that the weighting coefficient corresponding to each transmitting port may also refer to the weighting coefficient corresponding to the angle vector and the delay vector.
  • the network device can, for example, precode the downlink reference signal based on the angle and time delay determined by the uplink channel measurement, so that the terminal device can perform downlink channel measurement based on the precoded reference signal. Since the network equipment precodes the reference signal based on the reciprocal angle and/or time delay of the uplink and downlink channels, the terminal equipment does not need to feed back spatial and/or frequency domain vectors (such as the above-mentioned angle vector and/or delay vector) , which greatly reduces the feedback overhead of the terminal equipment.
  • the terminal device performs channel measurement based on the received precoding reference signal
  • the measured frequency domain channel is converted to the time domain, and the value obtained by the time domain conversion is fed back as the weighting coefficient of the angle-delay pair.
  • each group of weighting coefficients in the P group of weighting coefficients includes R'weighting coefficients, and the p-th group of weighting coefficients is obtained by comparing the The channel information between the p transmitting ports and one or more of the R receiving ports is obtained by time-domain transformation; R ⁇ R' ⁇ 1, and R'is an integer.
  • each group of weighting coefficients can correspond to a transmitting port, and the weighting coefficients in each group of weighting coefficients can be obtained by time-domain transformation of channel information between a transmitting port and a receiving port, or by a transmitting port and a receiving port.
  • the weighting of channel information among multiple receiving ports is obtained by time-domain transformation. This application does not limit this.
  • each group of weighting coefficients in the P group of weighting coefficients includes R weighting coefficients corresponding to the R receiving ports, and the r-th weighting coefficient in the p-th group of weighting coefficients is calculated by comparing the p-th group of weighting coefficients.
  • the channel information between each transmitting port and the r-th receiving port among the R receiving ports is obtained by time-domain transformation.
  • each weighting coefficient in each group of weighting coefficients may be obtained by time-domain transformation of channel information between a transmitting port and a receiving port.
  • the method further includes: performing time domain processing on the vector determined by the channel information between the p-th transmitting port and the r-th receiving port Transform to obtain a transformed vector, the r-th weighting coefficient in the p-th group of weighting coefficients is the n p, r- th value in the vector obtained by the time domain transform; wherein, the p-th transmitting The vector determined by the channel information between the port and the r-th receiving port includes N values, and the N values include the corresponding N frequency domain units for carrying the reference signal of the p-th transmitting port.
  • Channel information, 0 ⁇ n p, r ⁇ N-1, N ⁇ 1, n p, r and N are all integers.
  • the time domain transform includes: inverse fast Fourier transform (IFFT) or inverse discrete Fourier transform (IDFT).
  • IFFT inverse fast Fourier transform
  • IDFT inverse discrete Fourier transform
  • n p,r are predefined values.
  • n p,r 0.
  • n p,r can be defined as 0.
  • n p,r is defined as 0 is explained in detail by taking IFFT as an example. But this should not constitute any limitation to this application. Since the way of time domain transformation is not limited to the above list, in different implementation ways , the definition of n p,r may also be different. This application does not limit this.
  • the first indication information is further used to indicate the value of n p,r corresponding to the channel between the p-th transmitting port and the r-th receiving port.
  • the terminal device can determine which of the N time-domain transform values is determined as the weighting coefficient by itself, that is, the terminal device can determine the value of n p,r by itself and report it to the network device.
  • the method further includes: filtering the transformed vector based on a predetermined filter coefficient to obtain the rth group of weighting coefficients.
  • Weighting coefficient wherein, the filter coefficient includes N elements, the N elements include a non-zero element and N-1 zero elements, and the non-zero element is the n p, rth element among the N elements.
  • the terminal device can select a value from the vector obtained by the time domain transform as the weighting coefficient.
  • the specific process of the terminal device using one of the N time-domain transform values as a weighting coefficient can be implemented through filtering.
  • the foregoing provides a filtering method, which performs filtering processing on the vector obtained by the above-mentioned time domain transformation through a predetermined filter coefficient, so that the terminal device can obtain a value that can be used as a weighting coefficient from the vector.
  • the filter coefficient may be expressed as [1 0... 0] 1 ⁇ N, for example .
  • a channel measurement method is provided.
  • the method may be executed by a terminal device, or may also be executed by a component (such as a chip or a chip system, etc.) configured in the terminal device.
  • the method includes: generating second indication information for indicating P groups of weighting coefficients corresponding to P transmission ports, and the reference signal of each transmission port in the P transmission ports is based on at least a time delay
  • the vector is obtained by precoding the reference signal, and the weighting coefficient corresponding to each transmission port in the P transmission ports and the delay vector corresponding to each transmission port are used to construct the precoding matrix; wherein, corresponding to the P transmission ports
  • the p-th group of weighting coefficients of the p-th transmit port is the sum of multiple values obtained by filtering the channel information of one or more frequency domain unit groups.
  • the domain unit group includes a plurality of frequency domain units, and the total number of frequency domain units included in the one or more frequency domain unit groups is the number of frequency domain units used to carry the reference signal of the p-th transmit port,
  • the p-th transmitting port is any one of the P transmitting ports, 0 ⁇ p ⁇ P-1, P ⁇ 1, and both p and P are integers; the second indication information is sent.
  • the above-mentioned reference signal corresponding to each transmission port may be obtained by precoding based on the delay vector, or may be obtained by precoding based on the angle vector and the delay vector. This application does not limit this.
  • the terminal device can perform channel measurement based on the received reference signal to feed back the weighting coefficient corresponding to each transmission port. It can be understood that the weighting coefficient corresponding to each transmitting port may also refer to the weighting coefficient corresponding to the angle vector and the delay vector.
  • the network device may, for example, precode the downlink reference signal based on the time delay determined by the uplink channel measurement, so that the terminal device performs downlink channel measurement according to the precoded reference signal. Since the network device precodes the reference signal based on the reciprocal delay of the uplink and downlink channels, the terminal device does not need to feed back relevant information in the frequency domain (such as the above-mentioned delay vector), which greatly reduces the feedback overhead of the terminal device.
  • the method further includes: based on a predetermined filter coefficient corresponding to the p-th transmit port, respectively, the one or more frequency domain unit groups The channel information of is filtered to obtain the filtered value; the filtered values of the one or more frequency domain unit groups are summed to obtain the weighting coefficient corresponding to the p-th transmitting port.
  • the terminal device can filter the channel information corresponding to each transmission port based on the filter coefficient corresponding to the transmission port.
  • the channel information corresponding to the transmission port may be obtained by the terminal device based on the channel estimation of the reception of one reference signal by the transmission port.
  • the method further comprising: based on the relevant parameters latency or delay [tau] p [tau] p-p of the transmit port corresponding to the determined filter coefficients , Where each delay corresponds to a delay vector.
  • the filter coefficient is related to the delay corresponding to the transmitting port. That is to say, the filter coefficient used by the terminal device to filter the channel information corresponding to a certain transmitting port is related to the time delay corresponding to the transmitting port.
  • the filter coefficient is:
  • Is a correlation matrix which represents the correlation between frequency domain units in a frequency domain unit group used to carry the reference signal of the p-th transmit port
  • Is a correction value used to correct Make corrections
  • N represents the number of frequency domain units used to carry the reference signal of the p-th transmit port, and N>1 and is Integer For right Correlation matrix obtained by correction
  • SNR is the signal-to-noise ratio
  • I represents the identity matrix.
  • Wiener filter coefficients An example of Wiener filter coefficients is given above.
  • a correction value related to the time delay is introduced into the Wiener filter coefficient, which can realize the compensation of the Wiener filter coefficient in the prior art.
  • the correction value is related to the delay corresponding to the transmitting port, and makes full use of the correlation between the pilots on multiple frequency domain units of the same port, so that the filtered channel information corresponding to each frequency domain unit It is more accurate, and enables a greater degree of joint filtering for the originally discontinuous equivalent channel. This can alleviate the inaccurate channel estimation problem caused by the inability to bind frequency domain resources in the current technology.
  • Wiener filter coefficients listed above are only examples and should not constitute any limitation to this application. This application does not limit the specific form of the filter coefficient.
  • the method further includes: receiving third indication information, where the third indication information is used to indicate that each of the P transmission ports corresponds to Delay or delay related parameters, each delay corresponds to a delay vector.
  • the terminal device By instructing the terminal device with the delay or delay-related coefficients corresponding to each transmission port, it is convenient for the terminal device to determine the above-mentioned filter coefficients, thereby realizing the filtering of the estimated channel information.
  • the third indication information indicates the delay corresponding to each transmission port of the P transmission ports as the delay corresponding to each transmission port.
  • the third indication information indicates the relevant parameters of the delay corresponding to each of the P transmission ports as: the delay ⁇ 0 corresponding to the first transmission port among the P ports, and The difference ⁇ between the delays corresponding to the remaining ports except the first transmitting port among the P transmitting ports and the delay corresponding to the first transmitting port.
  • a communication device which includes various modules or units for executing the method in any one of the possible implementation manners of the first aspect.
  • a communication device including a processor.
  • the processor is coupled with the memory and can be used to execute instructions in the memory to implement the method in any one of the possible implementation manners of the first aspect.
  • the communication device further includes a memory.
  • the communication device further includes a communication interface, and the processor is coupled with the communication interface.
  • the communication device is a terminal device.
  • the communication interface may be a transceiver, or an input/output interface.
  • the communication device is a chip configured in a terminal device.
  • the communication interface may be an input/output interface.
  • the transceiver may be a transceiver circuit.
  • the input/output interface may be an input/output circuit.
  • a communication device including various modules or units for executing the method in any one of the possible implementation manners of the second aspect.
  • a communication device including a processor.
  • the processor is coupled with the memory, and can be used to execute instructions in the memory to implement the method in any one of the possible implementation manners of the second aspect.
  • the communication device further includes a memory.
  • the communication device further includes a communication interface, and the processor is coupled with the communication interface.
  • the communication device is an access network device.
  • the communication interface may be a transceiver, or an input/output interface.
  • the communication device is a chip configured in an access network device.
  • the communication interface may be an input/output interface.
  • the transceiver may be a transceiver circuit.
  • the input/output interface may be an input/output circuit.
  • a processor 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 executes the method in any one of the possible implementation manners of the first aspect and the second aspect.
  • the above-mentioned processor may be a chip, the input circuit may be an input pin, the output circuit may be an output pin, and the processing circuit may be a transistor, a gate circuit, a flip-flop, and various logic circuits.
  • the input signal received by the input circuit may be received and input by, for example, but not limited to, a receiver, and the signal output by the output circuit may be, for example, but not limited to, output to the transmitter and transmitted by the transmitter, and the input circuit and output
  • the circuit can be the same circuit, which is used 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.
  • a processing device including a processor and a memory.
  • the processor is used to read instructions stored in the memory, and can receive signals through a receiver, and transmit signals through a transmitter, so as to execute the method in any one of the possible implementation manners of the first aspect and the second aspect.
  • processors there are one or more processors and one or more memories.
  • the memory may be integrated with the processor, or the memory and the processor may be provided separately.
  • the memory can be a non-transitory (non-transitory) memory, such as a read only memory (ROM), which can be integrated with the processor on the same chip, or can be set in different On the chip, the embodiment of the present application does not limit the type of the memory and the setting mode of the memory and the processor.
  • ROM read only memory
  • sending instruction information may be a process of outputting instruction information from the processor
  • receiving capability information may be a process of the processor receiving input capability information.
  • the processed output data may be output to the transmitter, and the input data received by the processor may come from the receiver.
  • the transmitter and receiver can be collectively referred to as a transceiver.
  • the device in the above eighth aspect may be a chip, and the processor may be implemented by hardware or software.
  • the processor When implemented by hardware, the processor may be a logic circuit, an integrated circuit, etc.; when implemented by software
  • the processor may be a general-purpose processor, which is implemented by reading software codes stored in the memory.
  • the memory may be integrated in the processor, may be located outside the processor, and exist independently.
  • a computer program product includes: a computer program (also called code, or instruction), which when the computer program is executed, causes a computer to execute the first aspect and the first aspect described above.
  • the method in any one of the two possible implementation modes.
  • a computer-readable medium stores a computer program (also called code, or instruction) when it runs on a computer, so that the computer executes the first aspect and the first aspect described above.
  • the method in any one of the two possible implementation modes.
  • a communication system including the aforementioned terminal device and network device.
  • FIG. 1 is a schematic diagram of the architecture of a communication system applicable to the channel measurement method provided by an embodiment of the present application;
  • FIG. 2 is a schematic diagram of precoding a reference signal based on a delay vector according to an embodiment of the present application
  • FIG. 3 is a schematic flowchart of a channel measurement method provided by an embodiment of the present application.
  • FIG. 4 is a schematic flowchart of a channel measurement method provided by another embodiment of the present application.
  • FIG. 5 is a schematic flowchart of a channel measurement method provided by another embodiment of the present application.
  • FIG. 6 is a schematic flowchart of a channel measurement method provided by still another embodiment of the present application.
  • FIG. 7 is a schematic block diagram of a communication device provided by an embodiment of the present application.
  • FIG. 8 is a schematic structural diagram of a terminal device provided by an embodiment of the present application.
  • Fig. 9 is a schematic structural diagram of a network device provided by an embodiment of the present application.
  • LTE Long Term Evolution
  • FDD frequency division duplex
  • UMTS time division duplex
  • WiMAX worldwide interoperability for microwave access
  • 5G mobile communication system may include non-standalone (NSA) and/or standalone (SA).
  • the technical solution provided in this application can also be applied to machine type communication (MTC), inter-machine communication long-term evolution technology (Long Term Evolution-machine, LTE-M), and device-to-device (D2D) Network, machine to machine (M2M) network, Internet of things (IoT) network or other networks.
  • MTC machine type communication
  • LTE-M inter-machine communication long-term evolution technology
  • D2D device-to-device
  • M2M machine to machine
  • IoT Internet of things
  • the IoT network may include, for example, the Internet of Vehicles.
  • V2X vehicle to other devices
  • V2X vehicle to other devices
  • V2X vehicle to other devices
  • V2X vehicle to other devices
  • the V2X may include: vehicle to vehicle (V2V) communication, and the vehicle communicates with Infrastructure (vehicle to infrastructure, V2I) communication, vehicle to pedestrian communication (V2P) or vehicle to network (V2N) communication, etc.
  • V2V vehicle to vehicle
  • V2I infrastructure
  • V2P vehicle to pedestrian communication
  • V2N vehicle to network
  • the network device may be any device with a wireless transceiver function.
  • This equipment includes but is not limited to: evolved Node B (eNB), radio network controller (RNC), Node B (NB), base station controller (BSC) , Base transceiver station (BTS), home base station (for example, home evolved NodeB, or home Node B, HNB), baseband unit (BBU), wireless fidelity (wireless fidelity, WiFi) system Access point (AP), wireless relay node, wireless backhaul node, transmission point (TP), or transmission and reception point (TRP), etc., can also be 5G, such as NR ,
  • the gNB may include a centralized unit (CU) and a DU.
  • the gNB may also include an active antenna unit (AAU).
  • CU implements some functions of gNB, and DU implements some functions of gNB.
  • CU is responsible for processing non-real-time protocols and services, implementing radio resource control (RRC), and packet data convergence protocol (PDCP) The function of the layer.
  • RRC radio resource control
  • PDCP packet data convergence protocol
  • the DU is responsible for processing physical layer protocols and real-time services, and implements the functions of the radio link control (RLC) layer, medium access control (MAC) layer, and physical (physical, PHY) layer.
  • RLC radio link control
  • MAC medium access control
  • PHY physical layer
  • the network device may be a device that includes one or more of a CU node, a DU node, and an AAU node.
  • the CU can be divided into network equipment in an access network (radio access network, RAN), and the CU can also be divided into network equipment in a core network (core network, CN), which is not limited in this application.
  • the network equipment provides services for the cell, and the terminal equipment communicates with the cell through the transmission resources (for example, frequency domain resources, or spectrum resources) allocated by the network equipment.
  • the cell may belong to a macro base station (for example, a macro eNB or a macro gNB, etc.) , It may also belong to the base station corresponding to the small cell, where the small cell may include: metro cell, micro cell, pico cell, femto cell, etc. These small cells have the characteristics of small coverage and low transmit power, and are suitable for providing high-speed data transmission services.
  • terminal equipment may also be referred to as user equipment (UE), access terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile equipment, user terminal, Terminal, wireless communication equipment, user agent or user device.
  • UE user equipment
  • the terminal device may be a device that provides voice/data connectivity to the user, for example, a handheld device with a wireless connection function, a vehicle-mounted device, and so on.
  • some examples of terminals can be: mobile phones (mobile phones), tablets (pads), computers with wireless transceiver functions (such as laptops, palmtop computers, etc.), mobile Internet devices (mobile internet devices, MID), virtual reality Virtual reality (VR) equipment, augmented reality (AR) equipment, wireless terminals in industrial control, wireless terminals in self-driving (self-driving), and wireless in remote medical (remote medical) Terminals, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, cellular phones, cordless Telephone, session initiation protocol (SIP) telephone, wireless local loop (WLL) station, personal digital assistant (PDA), handheld device with wireless communication function, computing device or connection Other processing equipment to wireless modems, in-vehicle equipment, wearable equipment, terminal equipment in the 5G network, or
  • wearable devices can also be called wearable smart devices, which are the general term for using wearable technology to intelligently design daily wear and develop wearable devices, such as glasses, gloves, watches, clothing and shoes.
  • a wearable device is a portable device that is directly worn on the body or integrated into the user's clothes or accessories.
  • Wearable devices are not only a kind of hardware device, but also realize powerful functions through software support, data interaction, and cloud interaction.
  • wearable smart devices include full-featured, large-sized, complete or partial functions that can be achieved without relying on smart phones, such as smart watches or smart glasses, and only focus on a certain type of application function, and need to cooperate with other devices such as smart phones.
  • the terminal device may also be a terminal device in an Internet of Things (IoT) system.
  • IoT Internet of Things
  • IoT is an important part of the development of information technology in the future. Its main technical feature is to connect objects to the network through communication technology, so as to realize the intelligent network of human-machine interconnection and interconnection of things. IoT technology can achieve massive connections, deep coverage, and power-saving terminals through, for example, narrowband NB technology.
  • terminal devices can also include sensors such as smart printers, train detectors, gas stations, etc.
  • the main functions include collecting data (some terminal devices), receiving control information and downlink data from network devices, and sending electromagnetic waves to transmit uplink data to network devices. .
  • FIG. 1 shows a schematic diagram of a communication system 100 applicable to the method provided in the embodiment of the present application.
  • the communication system 100 may include at least one network device, such as the network device 101 in the 5G system shown in FIG. 1; the communication system 100 may also include at least one terminal device, as shown in FIG. Terminal equipment 102 to 107. Wherein, the terminal devices 102 to 107 may be mobile or fixed.
  • the network device 101 and one or more of the terminal devices 102 to 107 can communicate through a wireless link.
  • Each network device can provide communication coverage for a specific geographic area, and can communicate with terminal devices located in the coverage area. For example, the network device can send configuration information to the terminal device, and the terminal device can send uplink data to the network device based on the configuration information; for another example, the network device can send downlink data to the terminal device. Therefore, the network device 101 and the terminal devices 102 to 107 in FIG. 1 constitute a communication system.
  • the terminal devices can communicate directly.
  • D2D technology can be used to realize direct communication between terminal devices.
  • D2D technology can be used for direct communication.
  • the terminal device 106 and the terminal device 107 may communicate with the terminal device 105 individually or at the same time.
  • the terminal devices 105 to 107 may also communicate with the network device 101, respectively. For example, it can directly communicate with the network device 101.
  • the terminal devices 105 and 106 in the figure can directly communicate with the network device 101; it can also communicate with the network device 101 indirectly, as the terminal device 107 in the figure communicates with the network device via the terminal device 106. 101 communication.
  • FIG. 1 exemplarily shows a network device, multiple terminal devices, and communication links between each communication device.
  • the communication system 100 may include multiple network devices, and the coverage of each network device may include other numbers of terminal devices, for example, more or fewer terminal devices. This application does not limit this.
  • Each of the aforementioned communication devices may be configured with multiple antennas.
  • the plurality of antennas may include at least one transmitting antenna for transmitting signals and at least one receiving antenna for receiving signals.
  • each communication device additionally includes a transmitter chain and a receiver chain.
  • Those of ordinary skill in the art can understand that they can all include multiple components related to signal transmission and reception (such as processors, modulators, multiplexers, etc.). , Demodulator, demultiplexer or antenna, etc.). Therefore, multiple antenna technology can be used to communicate between network devices and terminal devices.
  • the wireless communication system 100 may also include other network entities such as a network controller and a mobility management entity, and the embodiment of the present application is not limited thereto.
  • the processing procedure of the downlink signal at the physical layer before transmission may be executed by a network device, or may be executed by a chip configured in the network device.
  • network devices For the convenience of description, the following are collectively referred to as network devices.
  • Network equipment can process code words on physical channels.
  • the codeword may be coded bits that have been coded (for example, including channel coding).
  • the codeword is scrambling to generate scrambled bits.
  • the scrambled bits undergo modulation mapping (modulation mapping) to obtain modulation symbols.
  • Modulation symbols are mapped to multiple layers, or transmission layers, through layer mapping.
  • the modulation symbols after layer mapping are precoding (precoding) to obtain a precoded signal.
  • the precoded signal is mapped to multiple REs after resource element (resource element, RE) mapping. These REs are then modulated by orthogonal frequency division multiplexing (OFDM) and then transmitted through an antenna port (antenna port).
  • OFDM orthogonal frequency division multiplexing
  • Precoding technology When the channel status is known, the network equipment can process the signal to be sent with the help of a precoding matrix that matches the channel status, so that the precoded signal to be sent is adapted to the channel, thereby This reduces the complexity for the receiving device to eliminate the influence between channels. Therefore, through the precoding processing of the signal to be transmitted, the quality of the received signal (for example, the signal to interference plus noise ratio (SINR), etc.) can be improved. Therefore, the use of precoding technology can realize the transmission on the same time-frequency resource between the sending device and multiple receiving devices, that is, the realization of multiple user multiple input multiple output (MU-MIMO).
  • SINR signal to interference plus noise ratio
  • the sending device may also perform precoding in other ways. For example, when channel information (such as but not limited to a channel matrix) cannot be obtained, precoding is performed using a preset precoding matrix or a weighting processing method. For the sake of brevity, its specific content will not be repeated here.
  • Channel reciprocity In some communication modes, such as TDD, the uplink and downlink channels transmit signals on the same frequency domain resources and different time domain resources. In a relatively short time (for example, 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.
  • the network equipment Based on the reciprocity of the uplink and downlink channels, the network equipment can measure the uplink channel based on the uplink reference signal, such as a sounding reference signal (SRS).
  • SRS sounding reference signal
  • the downlink channel can be estimated according to the uplink channel, so that the precoding matrix for downlink transmission can be determined.
  • the uplink and downlink channels do not have complete reciprocity, and the uplink channel is used to determine the precoding matrix for downlink transmission. It cannot be adapted to the downlink channel.
  • the uplink and downlink channels in the FDD mode still have partial reciprocity, for example, the reciprocity of angle and the reciprocity of delay. Therefore, angle and delay can also be called reciprocity parameters.
  • Multipath time delay causes frequency selective fading, which is the change of frequency domain channel.
  • the time delay is the transmission time of the wireless signal on different transmission paths, which is determined by the distance and speed, and has nothing to do with the frequency domain of the wireless signal.
  • signals are transmitted on different transmission paths, there are different transmission delays due to different distances. Since the physical location between the network device and the terminal device is fixed, the multipath distribution of the uplink and downlink channels is the same in terms of delay. Therefore, the uplink and downlink channels in the FDD mode with delay can be considered the same, or in other words, reciprocal.
  • the angle may refer to the angle of arrival (AOA) at which the signal reaches the receiving antenna via the wireless channel, and may also refer to the angle of departure (AOD) at which the signal is transmitted through the transmitting antenna.
  • AOA angle of arrival
  • AOD angle of departure
  • the angle may refer to the angle of arrival at which the uplink signal reaches the network device, and may also refer to the angle of departure at which the network device transmits the downlink signal. Due to the reciprocity of the transmission paths of the uplink and downlink channels on different frequencies, the arrival angle of the uplink reference signal and the departure angle of the downlink reference signal can be considered to be reciprocal.
  • each angle can be characterized by an angle vector.
  • Each delay can be characterized by a delay vector. Therefore, in the embodiment of the present application, an angle vector may represent an angle, and a delay vector may represent a time delay.
  • Reference signal (RS) and precoding reference signal may also be called a pilot (pilot), reference sequence, etc.
  • the reference signal may be a reference signal used for channel measurement.
  • the reference signal may be a channel state information reference signal (CSI-RS) used for downlink channel measurement, or it may be an SRS used for uplink channel measurement.
  • CSI-RS channel state information reference signal
  • SRS uplink channel measurement
  • the precoding reference signal may be a reference signal obtained by precoding the reference signal.
  • the precoding may specifically include beamforming and/or phase rotation. Wherein, beamforming may be realized by precoding the downlink reference signal based on one or more angle vectors, and phase rotation may be realized by precoding the downlink reference signal by one or more delay vectors, for example.
  • the reference signal obtained after precoding is called a precoding reference signal; the reference signal that has not been precoded is referred to as a reference signal for short .
  • precoding the downlink reference signal based on one or more angle vectors can also be referred to as loading one or more angle vectors on the downlink reference signal to achieve beamforming.
  • Precoding the downlink reference signal based on one or more delay vectors can also be referred to as loading one or more delay vectors on the downlink reference signal to achieve phase rotation.
  • Port It can include a transmitting port and a receiving port.
  • the transmitting port can be understood as a virtual antenna recognized by the receiving device.
  • the port may refer to the transmitting antenna port.
  • the reference signal of each transmit antenna port may be a reference signal that has not been precoded.
  • the transmitting antenna port may refer to an actual independent transmitting unit (transceiver unit, TxRU).
  • the port may also refer to a port after beamforming.
  • the reference signal of each port may be a precoding reference signal obtained by precoding the reference signal based on an angle vector. It is understandable that if beamforming is performed on the reference signal, the number of ports may refer to the number of ports of the precoding reference signal. The number of ports of the precoding reference signal may be less than the number of transmitting antenna ports.
  • a port may also refer to a port after phase rotation.
  • the reference signal of each port may be a precoding reference signal that is precoded based on a delay vector and sent through a transmit antenna port. This port may also be referred to as the port of the precoding reference signal.
  • the port may also refer to the port after beamforming and phase rotation.
  • the reference signal of each port may be a precoding reference signal obtained by precoding the reference signal based on an angle vector and a delay vector. This port may also be referred to as the port of the precoding reference signal.
  • the reference signal of each port can be transmitted through one or more frequency domain units.
  • the transmitting antenna port when the transmitting antenna port is involved, it may refer to the number of ports that have not been spatially pre-coded. That is, it is the actual number of independent transmission units.
  • a port in different embodiments, it may refer to a transmitting antenna port, or it may refer to a port of a precoding reference signal.
  • the specific meaning expressed by the port can be determined according to specific embodiments.
  • the port of the precoding reference signal is referred to as the reference signal port.
  • the receiving port can be understood as the receiving antenna of the receiving device.
  • the receiving port may refer to the receiving antenna of the terminal device.
  • Angle vector it can be understood as a precoding vector for beamforming the reference signal.
  • the reference signal emitted by the transmitting device can have a certain spatial directivity. Therefore, the process of precoding the reference signal based on the angle vector can also be regarded as a process of spatial domain (or simply, spatial domain) precoding. Therefore, the angle vector can also be called a spatial vector, a beam vector, and so on.
  • the number of ports of the precoding reference signal obtained by precoding the reference signal based on one or more angle vectors is the same as the number of angle vectors.
  • the antenna port dimension can be reduced by spatial precoding, thereby reducing pilot overhead.
  • the angle vector can be a vector of length T.
  • the angle vector is a Discrete Fourier Transform (DFT) vector.
  • the DFT vector may refer to the vector in the DFT matrix.
  • the angle vector is the conjugate transpose vector of the DFT vector.
  • the DFT conjugate transpose vector may refer to the column vector in the conjugate transpose matrix of the DFT matrix.
  • the angle vector is an oversampled DFT vector.
  • the oversampled DFT vector may refer to the vector in the oversampled DFT matrix.
  • the angle vector may be, for example, the two-dimensional (2 dimensions, 2D)-DFT vector v defined in the type II (type II) codebook in the NR protocol TS 38.214 version 15 (release 15, R15). l,m .
  • the angle vector can be a 2D-DFT vector or an oversampled 2D-DFT vector.
  • I 1 is the number of antenna ports in the same polarization direction included in each column (or row) of the antenna array
  • I 2 is the number of antenna ports in the same polarization direction included in each row (or column) of the antenna array.
  • T I 1 ⁇ I 2 .
  • O 1 and O 2 are oversampling factors. i 1 and i 2 satisfy 0 ⁇ i 1 ⁇ (O 1 ⁇ I 1 -1), 0 ⁇ i 2 ⁇ (O 2 ⁇ I 2 -1).
  • the angle vector is a steering vector of a uniform linear array (ULA).
  • ULA uniform linear array
  • the steering vector can represent the phase difference between the response of different antennas for the angle of arrival of a path.
  • the angle vector is a steering vector of a uniform plane array (UPA).
  • the steering vector may be, for example, a steering vector including horizontal angle and pitch angle information.
  • ⁇ k is the horizontal angle, Is the elevation angle
  • u k is the unit sphere basis vector corresponding to the k-th angle:
  • the angle vector is denoted as a( ⁇ k ).
  • the channel measured by the terminal device according to the received precoding reference signal is equivalent to the channel loaded with the angle vector.
  • loading the angle vector a( ⁇ k ) to the downlink channel V can be expressed as Va( ⁇ k ).
  • the transmitting device is configured with a single-polarized antenna
  • the number of transmitting antenna ports is T; the number of frequency domain units is N, N ⁇ 1, and N is an integer.
  • the channel estimated based on the received reference signal may be a matrix with a dimension of N ⁇ T. If the reference signal is spatially pre-coded based on an angle vector, the angle vector can be loaded on the reference signal respectively. Since the dimension of the angle vector is T ⁇ 1, for one receiving port of the receiving device, the dimension of the channel estimated based on the precoding reference signal may be N ⁇ 1. And on each receiving port and each frequency domain unit, the dimension of the channel estimated by the terminal device based on the received precoding reference signal may be 1 ⁇ 1.
  • angle vector is a form for expressing an angle proposed in this application.
  • the angle vector is only named for the convenience of distinguishing from the time delay, and should not constitute any limitation in this application. This application does not exclude the possibility of defining other names in future agreements to represent the same or similar meanings.
  • Time delay vector It can also be called a frequency domain vector.
  • the delay vector can be used as a vector that represents the changing law of the channel in the frequency domain.
  • multipath delay causes frequency selective fading.
  • the time delay of the signal in the time domain can be equivalent to the phase gradual change in the frequency domain.
  • the Fourier transform can transform the signal into the frequency domain:
  • the signal can be transformed into the frequency domain by Fourier transform: Among them, ⁇ is the frequency variable, the phase rotation corresponding to different frequencies is different; t and tt 0 represent the time delay.
  • the change law of the phase of the channel in each frequency domain unit can be represented by a delay vector.
  • the delay vector can be used to represent the delay characteristics of the channel.
  • Precoding the reference signal based on the delay vector can essentially refer to the phase rotation of each frequency domain unit in the frequency domain based on the elements in the delay vector, so as to pre-encode the reference signal to pre-encode the frequency caused by the multipath delay.
  • Precoding the reference signal based on different delay vectors is equivalent to performing phase rotation on each frequency domain unit of the channel based on different delay vectors.
  • different resources for example, resource elements (resource elements, RE)
  • RE resource elements
  • the network device may separately precode the reference signal based on each of the L time delay vectors.
  • the length of the delay vector is N, and N may refer to the number of frequency domain units used to carry the reference signal (for example, a reference signal that has not been precoded or a reference signal that has been precoded), N ⁇ 1, and N is an integer.
  • the delay vector is taken from the DFT matrix.
  • Each vector in the DFT matrix can be referred to as a DFT vector.
  • O f is the oversampling factor, O f ⁇ 1; k is the index of the DFT vector, and satisfies 0 ⁇ k ⁇ O f ⁇ N-1 or 1-O f ⁇ N ⁇ k ⁇ 0.
  • the delay vector is denoted as b( ⁇ l ).
  • a resource block is taken as an example of a frequency domain unit to illustrate a specific process of frequency domain precoding on a reference signal.
  • each frequency domain unit includes only one RB for carrying a reference signal.
  • each frequency domain unit may include one or more RBs for carrying reference signals.
  • the network device may load the delay vector on the multiple RBs for carrying reference signals in each frequency domain unit.
  • the reference signal loaded with the delay vector can be transmitted to the terminal device through the downlink channel, the channel measured by the terminal device according to the received precoding reference signal is equivalent to the channel loaded with the delay vector.
  • the reference signal is pre-coded in the frequency domain based on a delay vector of length N, the N elements in the delay vector can be loaded on the reference signal carried on the N RBs. Loading the nth element in the delay vector to the channel V (n) on the nth RB can be expressed as
  • the frequency-domain precoding of the reference signal based on the delay vector may be performed before or after the resource mapping, which is not limited in this application.
  • Fig. 2 shows an example of frequency-domain precoding of reference signals carried on N RBs based on the delay vector b( ⁇ 1 ).
  • the N RBs may include RB#0, RB#1 to RB#N-1.
  • Each of the N RBs includes one or more REs for carrying the reference signal.
  • the RE used to carry the reference signal may be the RE on the first time domain symbol and the first subcarrier in each RB.
  • the time domain vector b( ⁇ 1 ) can be loaded on the RE on the first time domain symbol and the first subcarrier in each RB.
  • the first time domain symbol in each of the N RBs and the reference signal carried on the RE on the first subcarrier may be reference signals corresponding to the same port.
  • the N frequency domain units can be phase rotated.
  • the N elements in the delay vector may correspond to the N frequency domain units one-to-one.
  • the 0th element in the frequency domain vector b( ⁇ 1) Can be loaded on RB#0
  • the first element in the frequency domain vector b( ⁇ 1) Can be loaded on RB#1
  • N-1 elements in the delay vector b( ⁇ 1) Can be loaded on RB#N-1.
  • the nth element in the delay vector b( ⁇ 1) Can be loaded on RB#n.
  • the RB is only an example of a frequency domain unit, and should not constitute any limitation to this application. This application does not limit the specific definition of the frequency domain unit.
  • the delay vector is a form of time delay proposed in this application.
  • the delay vector is only named for the convenience of distinguishing from the angle, and should not constitute any limitation in this application. This application does not exclude the possibility of defining other names in future agreements to represent the same or similar meanings.
  • the network device is configured with a single-polarized antenna
  • the number of transmitting antenna ports is T
  • the number of frequency domain units is N.
  • the channel estimated based on the received reference signal can be expressed as a matrix with a dimension of N ⁇ T.
  • the reference signal is precoded in the frequency domain based on L delay vectors
  • the channel estimated based on the received precoding reference signal can be expressed as a matrix with a dimension of N ⁇ L .
  • the dimension of the channel estimated by the terminal device based on the received precoding reference signal may be 1 ⁇ L.
  • Frequency domain unit a unit of frequency domain resources, which can represent different granularity of frequency domain resources.
  • the frequency domain unit may include, but is not limited to, for example, subband (subband), resource block (RB), resource block group (RBG), precoding resource block group (PRG), and the like.
  • the network device may determine the precoding matrix corresponding to each frequency domain unit based on the feedback of the terminal device.
  • Angle delay pair It can also be called a space-frequency vector pair.
  • An angle delay pair can be a combination of an angle vector and a delay vector.
  • Each angle delay pair may include an angle vector and a delay vector. At least one of the angle vector and the delay vector included in any two angle delay pairs is different. In other words, each angle delay pair can be uniquely determined by an angle vector and a delay vector.
  • the precoding matrix used to precode the reference signal when the reference signal is precoded based on an angle vector a( ⁇ k ) and a delay vector b( ⁇ l ), the precoding matrix used to precode the reference signal can be expressed as a The product of the conjugate transpose of an angle vector and a time delay vector, for example, can be expressed as a( ⁇ k ) ⁇ b( ⁇ l ) H , and its dimension may be T ⁇ N.
  • the precoding matrix used for precoding the reference signal can also be expressed as the Kronecker product of an angle vector and a delay vector, for example, it can be expressed as Its dimension can be T ⁇ N.
  • the precoding matrix used to precode the reference signal can also be expressed as the product of the conjugate transpose of a delay vector and an angle vector, or the Kronecker of a delay vector and an angle vector. Product, its dimension can be N ⁇ T.
  • the precoding matrix used for precoding the reference signal may also be expressed as a mathematical transformation of various expressions above. For the sake of brevity, I will not list them all here.
  • the weighted sum of one or more angle delay pairs may be used to determine the space-frequency matrix.
  • a matrix with a dimension T ⁇ N determined based on an angle delay pair can be referred to as a component of the space-frequency matrix, or simply referred to as a space-frequency component matrix.
  • a matrix with a dimension T ⁇ N determined by an angle delay pair is obtained by a( ⁇ k ) ⁇ b( ⁇ l ) H.
  • Space-frequency matrix In this embodiment of the application, the space-frequency matrix is an intermediate quantity used to determine the precoding matrix.
  • the space-frequency matrix may be determined based on the receiving port, and may also be determined based on the transmission layer.
  • the space-frequency matrix can be determined by the weighted sum of one or more angle delay pairs, so the dimension of the space-frequency matrix can also be N ⁇ T.
  • the space-frequency matrix can be referred to as the space-frequency matrix corresponding to the receiving port.
  • the space-frequency matrix corresponding to the receiving port can be used to construct the downlink channel matrix of each frequency domain unit, and then the precoding matrix corresponding to each frequency domain unit can be determined.
  • the channel matrix corresponding to a certain frequency domain unit may be, for example, a conjugate transpose of a matrix constructed from column vectors corresponding to the same frequency domain unit in the space-frequency matrix corresponding to each receiving port. For example, extracting the nth column vector in the space-frequency matrix corresponding to each receiving port, and arranging it from left to right according to the order of the receiving ports, a matrix of dimension T ⁇ R can be obtained.
  • R represents the number of receiving ports, R ⁇ 1 and is an integer.
  • the channel matrix V (n) of the nth frequency domain unit can be obtained.
  • the relationship between the channel matrix and the space-frequency matrix will be described in detail below, and the detailed description of the relationship between the two will be omitted here.
  • the space-frequency matrix can be referred to as the space-frequency matrix corresponding to the transmission layer.
  • the space-frequency matrix corresponding to the transmission layer can be directly used to determine the precoding matrix corresponding to each frequency domain unit.
  • the precoding matrix corresponding to a certain frequency domain unit may be constructed by, for example, column vectors corresponding to the same frequency domain unit in the space-frequency matrix corresponding to each transmission layer. For example, extract the nth column vector in the space-frequency matrix corresponding to each transmission layer, and arrange it from left to right according to the order of the transmission layer to obtain a matrix of dimension T ⁇ Z.
  • Z represents the number of transmission layers, Z ⁇ 1 and is an integer. This matrix can be used as the precoding matrix W (n) of the nth frequency domain unit.
  • the precoding matrix determined by the channel measurement method provided in the embodiments of the present application may be a precoding matrix directly used for downlink data transmission; it may also undergo some beamforming methods, such as zero forcing (ZF). ), minimum mean-squared error (MMSE), maximum signal-to-leakage-and-noise (SLNR), etc., to obtain the final precoding matrix for downlink data transmission.
  • ZF zero forcing
  • MMSE minimum mean-squared error
  • SLNR maximum signal-to-leakage-and-noise
  • the precoding matrix involved in the following may all refer to a precoding matrix determined based on the channel measurement method provided in this application.
  • the space-frequency matrix is an intermediate quantity proposed based on the frequency domain continuity of the channel that can be used to construct the precoding matrix.
  • C represents the angle vector with K
  • Each angle vector in and the weighting coefficient corresponding to each delay vector in the L delay vectors constitute a coefficient matrix.
  • Each element in C can represent the weighting coefficient of a corresponding angle vector pair.
  • the space-frequency component matrix is defined as determined by a( ⁇ k ) ⁇ b( ⁇ l ) H. From this, the dimension of the space-frequency matrix H DL can be determined as: the number of transmitting antenna ports ⁇ the number of frequency domain units. For example, the dimension of the space-frequency matrix corresponding to the downlink channel is T ⁇ N. In the following embodiments, unless otherwise specified, the space-frequency matrix refers to the aforementioned matrix H DL with a dimension of T ⁇ N.
  • the dimension of the channel matrix is defined as: the number of receiving ports ⁇ the number of transmitting ports, for example, the dimension of the downlink channel is R ⁇ T.
  • the dimension of the space-frequency matrix determined by the channel matrix is N ⁇ T, which is exactly the opposite of the dimension T ⁇ N of the aforementioned space-frequency matrix H DL. Therefore, in the embodiment of the present application, the real channel may be the conjugate transpose of the channel matrix determined by the above-mentioned space-frequency matrix H DL.
  • the downlink channel matrix determined by the space-frequency matrix H DL may be the conjugate transpose of the real channel.
  • the precoding matrix can be determined by the space frequency matrix H DL.
  • the precoding matrix of the nth frequency domain unit may be constructed by the nth column vector in the space frequency matrix corresponding to each transmission layer.
  • the conjugate transpose of the precoding matrix can be obtained by performing the SVD of the channel matrix V.
  • V H is SVD
  • the precoding matrix can just be obtained. Therefore, the space-frequency matrix H DL determined by the conjugate transpose of the real channel in the embodiment of the present application can be directly determined to obtain the precoding matrix corresponding to each frequency domain unit.
  • H DL SC DL F H deformation
  • H H DL C DL F H
  • H C DL F H
  • C DL F H C DL F H
  • C DL (H DL H S) H F.
  • H DL H is the space-frequency matrix determined by the real channel
  • H DL H S is the real channel after spatial precoding.
  • Each element of C DL in the coefficient matrix can be determined by multiplying a row in (H DL H S) H and a column in F respectively.
  • each element in the matrix coefficient C DL may be conjugated by a real channel H DL H S transpose (H DL H S) H and a row F is multiplied, or that is true
  • the conjugate transpose of a column of channel H DL H S is multiplied by a column of F.
  • the space-frequency matrix H DL determined based on the weighting coefficients of the angle delay pairs fed back by the terminal device may be obtained by the conjugate transpose of the real channel.
  • the space-frequency matrix in the embodiment of the present application may also be obtained by the conjugate transpose of the real channel V (ie, V H ).
  • the relationship between the real channel and the space-frequency matrix H DL is not fixed. Different definitions of the space-frequency matrix and the space-frequency component matrix may change the relationship between the real channel and the space-frequency matrix H DL.
  • the space-frequency matrix H DL can be obtained by the conjugate transposition of the real channel, or can be obtained by the transposition of the real channel.
  • the operations performed by the network equipment when loading the delay and angle are also different, and the operations performed by the terminal equipment during channel measurement and feedback also change accordingly .
  • this is only the implementation behavior of terminal equipment and network equipment, and should not constitute any limitation to this application.
  • the embodiments of the present application are only for ease of understanding, and show a situation where the space-frequency matrix is obtained by the conjugate transpose of a real channel.
  • This application does not limit the definition of the channel matrix, the dimension and definition of the space-frequency matrix, and the conversion relationship between the two. Similarly, this application does not limit the conversion relationship between the space-frequency matrix and the precoding matrix.
  • Antenna delay pair It can be a combination of a transmitting antenna port and a delay vector.
  • Each antenna delay pair may include a transmitting antenna port and a delay vector.
  • the transmit antenna ports and/or delay vectors included in any two antenna delay pairs are different.
  • each antenna delay pair can be uniquely determined by a transmitting antenna port and a delay vector.
  • the antenna delay pair can be understood as the expression form of the space-frequency basic unit determined by a transmitting antenna port and a delay vector, but it is not necessarily the only expression form. This application deals with the relationship between the transmitting antenna port and the delay vector.
  • the form of expression of the combination is not limited.
  • T The number of transmitting antenna ports in a polarization direction, T is a positive integer
  • P The number of transmit ports in a polarization direction, P is a positive integer
  • R the number of receiving ports, R is a positive integer
  • Z the number of transmission layers, Z is a positive integer
  • N the number of frequency domain units used to carry the reference signal, N is a positive integer
  • K angle vector number, K is a positive integer
  • L the number of delay vectors, L is a positive integer
  • J the number of polarization directions of the transmitting antenna, J is a positive integer
  • serial numbers can be started from 0.
  • the K angle vectors may include the 0th angle vector to the K-1th angle vector
  • the L delay vectors may include the 0th delay vector to the L-1th delay vector, etc., for brevity, here Not to list them all.
  • the specific implementation is not limited to this.
  • it can also be numbered consecutively starting from 1.
  • the K angle vectors may include the first angle vector to the Kth angle vector
  • the L delay vectors may include the first delay vector to the Lth delay vector, and so on.
  • the superscript T means transpose, such as AT means the transpose of matrix (or vector) A;
  • superscript * means conjugate, for example, A * means the conjugate of matrix (or vector) A;
  • superscript H means Conjugate transpose, for example, A H represents the conjugate transpose of matrix (or vector) A.
  • the angle vector and the delay vector are both column vectors as an example to illustrate the embodiments provided in this application, but this should not constitute any limitation to this application. Based on the same concept, those skilled in the art can also think of other more possible expressions.
  • used to indicate can include both used for direct indication and used for indirect indication.
  • the indication information may directly indicate A or indirectly indicate A, but it does not mean that A must be carried in the indication information.
  • the information indicated by the instruction information is called the information to be indicated.
  • the information to be indicated can be directly indicated, such as the information to be indicated or the information to be indicated. Indicates the index of the information, etc.
  • the information to be indicated can also be indicated indirectly 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, it is also possible to realize the indication of specific information by means of the pre-arranged order (for example, stipulated in the agreement) of the various information, thereby reducing the indication overhead to a certain extent.
  • the 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 attributes.
  • the specific instruction manner may also be various existing instruction manners, such as but not limited to the foregoing instruction manners and various combinations thereof.
  • the required instruction method can be selected according to specific needs.
  • the embodiment of the application does not limit the selected instruction method.
  • the instruction method involved in the embodiment of the application should be understood as covering that can make the instruction to be instructed Various methods for obtaining information to be indicated.
  • a row vector can be expressed as a column vector
  • a matrix can be expressed by the transpose matrix of the matrix
  • a matrix can also be expressed in the form of a vector or an array. It can be formed by connecting each row vector or column vector of the matrix to each other, and so on.
  • the information to be instructed can be sent together as a whole, or divided into multiple sub-information to be sent separately, and the sending period and/or sending timing of these sub-information can 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 pre-defined, for example, pre-defined 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, one or a combination of at least two of radio resource control signaling, media access control (media access control, MAC) layer signaling, and physical layer signaling.
  • radio resource control signaling such as packet radio resource control (RRC) signaling
  • MAC layer signaling for example, includes MAC control element (CE);
  • physical layer signaling for example, includes downlink control information (downlink control). information, DCI).
  • “pre-defined” or “pre-configured” can be realized by pre-saving corresponding codes, tables or other methods that can be used to indicate relevant information in the equipment (for example, including terminal equipment and network equipment).
  • the specific implementation is not limited.
  • "saving” may refer to storing in one or more memories.
  • the one or more memories may be provided separately, or integrated in an encoder or decoder, a processor, or a communication device.
  • the one or more memories may also be partly provided separately, and partly integrated in a decoder, a processor, or a communication device.
  • the type of the memory can be any form of storage medium, which is not limited in this application.
  • the “protocols” involved in the embodiments of the present application may refer to standard protocols in the communication field, for example, may include LTE protocol, NR protocol, and related protocols applied to future communication systems, which are not limited in this application.
  • At least one refers to one or more, and “multiple” refers to two or more.
  • And/or describes the association relationship of the associated objects, indicating that there can be three relationships, for example, A and/or B, which can mean: A alone exists, A and B exist at the same time, and B exists alone, where A, B can be singular or plural.
  • the character “/” generally indicates that the associated objects before and after are in an “or” relationship.
  • "The following at least one item (a)” or similar expressions refers to any combination of these items, including any combination of a single item (a) or a plurality of items (a).
  • At least one of a, b, and c can mean: a, or, b, or, c, or, a and b, or, a and c, or, b and c, or, a , B, and c.
  • a, b, and c can be single or multiple.
  • the transmitting port may refer to a port for transmitting a reference signal (such as a precoding reference signal).
  • the receiving port may refer to a port that receives a reference signal (such as a precoding reference signal, etc.).
  • the transmitting port may be a port on the network device side, and the receiving port may be a port on the terminal device side.
  • the terminal device shown in the following embodiments can be replaced with a component (such as a chip or a chip system) configured in the terminal device.
  • the network device shown in the following embodiments can also be replaced with components (such as a chip or a chip system) configured in the network device.
  • the embodiments shown below do not specifically limit the specific structure of the execution body of the method provided in the embodiments of the application, as long as the program can be run and recorded with the code of the method provided in the embodiments of the application to provide the method according to the embodiments of the application.
  • the execution subject of the method provided in the embodiments of the present application may be a terminal device or a network device, or a functional module in the terminal device or the network device that can call and execute the program.
  • This application provides a channel measurement method based on time domain transformation.
  • the terminal device can receive the precoding reference signal from one or more transmitting ports.
  • the terminal device may perform channel estimation based on the received precoding reference signal of each transmission port, and perform time domain transformation on channel information estimated on multiple frequency domain units corresponding to the same transmission port. That is, the channel change in the frequency domain is converted to the time domain to obtain the strongest value.
  • the terminal device feeds back the strongest obtained from the time domain transformation to the network device.
  • the value fed back by the terminal device to the network device is the weighting coefficient corresponding to the same transmitting port.
  • This application also provides a channel measurement method based on frequency domain filtering.
  • the terminal device can receive the precoding reference signal from one or more transmitting ports.
  • the terminal device may perform channel estimation based on the received precoding reference signal of each transmission port, and perform frequency domain filtering on the channel information obtained by the estimation.
  • the terminal device may use the frequency domain unit group as a unit to filter the channel information on the frequency domain units in the same frequency domain unit group.
  • the terminal device can perform filtering results on the channel information on the frequency domain units in the multiple frequency domain unit groups. Accumulate.
  • the terminal device can feed back the accumulated result to the network device.
  • the value fed back by the terminal device to the network device is the weighting coefficient corresponding to the same transmitting port.
  • the network device may precode the reference signal based on the delay vector and the angle vector, and may also precode the reference signal based on the delay vector or the angle vector, which is not limited in this application.
  • FIG. 3 is a schematic flowchart of a channel measurement method 300 provided by an embodiment of the present application from the perspective of device interaction.
  • the method 300 shown in FIG. 3 may include step 310 to step 340.
  • the steps in the method 300 are described in detail below.
  • the transmitting antenna of one polarization direction may be any one of the transmitting antennas of the J polarization directions configured by the network device. This application does not limit the number J of polarization directions of the transmitting antennas configured by the network equipment.
  • step 310 the terminal device receives a precoding reference signal.
  • the network device sends the precoding reference signal.
  • the network device may precode the reference signal based on K angle vectors and L delay vectors. From the K angle vectors and L delay vectors, various combinations of angle vectors and delay vectors can be obtained. The angle vector and/or delay vector in any two combinations are different. The angle vector and the delay vector in each combination can be used to pre-encode the reference signal to obtain a pre-encoded reference signal corresponding to one port. Therefore, the precoding reference signal obtained by the network device precoding based on the K angle vectors and the L delay vectors may correspond to one or more ports, and the precoding reference signal of each port may be based on one of the K angle vectors. The angle vector and one of the L delay vectors are obtained by precoding the reference signal. In other words, the precoding reference signal of each port may be obtained by precoding the reference signal based on a combination of an angle vector and a delay vector.
  • the network device can combine each of the K angle vectors and each of the L delay vectors in pairs to obtain the K ⁇ of the angle vector and the delay vector. L combinations, or in other words, K ⁇ L angle delay pairs are obtained. That is, the network device may precode the reference signal based on each of the K angle vectors and each of the L delay vectors.
  • the network device When the network device pre-encodes the reference signal based on the kth (1 ⁇ k ⁇ K, k is an integer) angle vector among the K angle vectors, it can traverse each of the L delay vectors for reference
  • the signal is pre-encoded; or, when the network device pre-encodes the reference signal based on the lth (1 ⁇ l ⁇ L, l is an integer) delay vector in the L delay vectors, it can traverse the K angle vectors
  • the reference signal is pre-coded for each angle vector of.
  • the K angle vectors can be regarded as common to each delay vector
  • the L delay vectors can also be regarded as common to each angle vector.
  • the K angle vectors and the L delay vectors are shared with each other.
  • the network device when it pre-encodes the reference signal based on the k-th angle vector among the K angle vectors, it can traverse the L k corresponding to the k-th angle vector (1 ⁇ L k ⁇ L, L k is an integer) each of the delay vectors pre-encodes the reference signal.
  • L in the above L delay vectors can satisfy: In this implementation manner, the delay vectors corresponding to at least two angle vectors are different.
  • the delay vectors corresponding to at least two angle vectors are different, which may mean that among the K angle vectors, at least two angle vectors correspond to different delay vectors, and the delay vectors corresponding to other angle vectors can be the same, or It can be different, and this application does not limit it. In other words, the delay vector corresponding to each angle vector is partially or completely different.
  • the delay vectors corresponding to the two angle vectors are different, which may mean that the delay vectors corresponding to the two angle vectors are completely different, that is, the delay vectors corresponding to the two angle vectors are not repeated, or in other words, there is no intersection.
  • the delay vector corresponding to the angle vector a( ⁇ 1 ) includes b( ⁇ 2 )
  • the delay vector corresponding to the angle vector a( ⁇ 2 ) includes b( ⁇ 1 ) and b( ⁇ 3 ).
  • the delay vectors corresponding to the two angle vectors are different.
  • the delay vectors corresponding to the two angle vectors are partially different, that is, the delay vectors corresponding to the two angle vectors are partially overlapped, but not completely the same, or ,
  • the delay vectors corresponding to the two angle vectors have an intersection, but they are not exactly the same.
  • the delay vector corresponding to a( ⁇ 1 ) includes b( ⁇ 2 ) and b( ⁇ 3 )
  • the delay vector corresponding to the angle vector a( ⁇ 2 ) includes b( ⁇ 1 ) and b( ⁇ 3 ).
  • the network device can obtain from the above K angle vectors and L delay vectors A combination of angle vector and delay vector.
  • the network device when it pre-encodes the reference signal based on the lth delay vector among the L delay vectors, it can traverse the K l (1 ⁇ K l ⁇ K, K l is an integer) each of the angle vectors pre-encodes the reference signal.
  • K in the above K angle vectors can satisfy: In this implementation, the angle vectors corresponding to at least two delay vectors are different.
  • the angle vectors corresponding to at least two delay vectors are different, which may mean that among the L delay vectors, at least two delay vectors correspond to different angle vectors, and the angle vectors corresponding to other delay vectors can be the same. It can also be different, which is not limited in this application. In other words, the angle vectors corresponding to the delay vectors are partially or completely different.
  • the angle vectors corresponding to the two delay vectors are different, which may mean that the angle vectors corresponding to the two delay vectors are completely different, that is, the angle vectors corresponding to the two delay vectors are not repeated, or in other words, there is no intersection.
  • the angle vector corresponding to the delay vector b( ⁇ 1 ) includes a( ⁇ 2 )
  • the angle vector corresponding to the delay vector b( ⁇ 2 ) includes a( ⁇ 1 ).
  • the angle vectors corresponding to the two delay vectors are different. It can also mean that the angle vectors corresponding to the two delay vectors are partially different.
  • the angle vectors corresponding to the two delay vectors are partially overlapped, but not completely the same, or ,
  • the angle vectors corresponding to the two delay vectors have an intersection, but they are not exactly the same.
  • the angle vector corresponding to the delay vector b( ⁇ 1 ) includes a( ⁇ 2 )
  • the angle vector corresponding to the delay vector b( ⁇ 2 ) includes a( ⁇ 1 ) and a( ⁇ 2 ).
  • the number of ports of the transmitted precoding reference signal can be determined by K angle vectors and L delay vectors.
  • the number of combinations. That is, the number of transmission ports P can be determined by the number of combinations determined by K angle vectors and L delay vectors.
  • the K angle vectors and the L delay vectors may be determined based on uplink channel measurement.
  • the network device may determine K angles and L delays according to the uplink channel matrix obtained in advance.
  • the K angles can be characterized by K angle vectors.
  • the L delays can be characterized by L delay vectors.
  • the uplink channel matrix may be a weighted sum of several space-frequency component matrices determined by the K angle vectors and L delay vectors.
  • the K angle vectors may be, for example, stronger K angle vectors determined from a predefined set of angle vectors.
  • the K angle vectors may be jointly determined for the L delay vectors, or may be determined separately for each of the L delay vectors. This application does not limit this.
  • each angle vector in the angle vector set is taken from a DFT matrix.
  • the K angle vectors can be determined by performing DFT on the uplink channel matrix, for example.
  • each angle vector in the angle vector set is a steering vector.
  • the L delay vectors may be, for example, stronger L delay vectors determined from a set of predefined delay vectors.
  • the L delay vectors may be jointly determined for the K angle vectors, or may be determined separately for each of the K angle vectors. This application does not limit this.
  • each delay vector in the delay vector set is taken from a DFT matrix.
  • the L delay vectors can be determined by performing DFT on the uplink channel matrix, for example.
  • the network device may use the joint angle and delay estimation (JADE) algorithm in the prior art to determine the K angle vectors and the strong one or more delays corresponding to each angle vector. vector.
  • the estimation algorithm may be, for example, multiple signal classification algorithm (MUSIC), Bartlett algorithm, or rotation invariant subspace algorithm (estimation of signal parameters via rotation invariant technology algorithm, ESPRIT), etc.
  • MUSIC multiple signal classification algorithm
  • Bartlett algorithm or rotation invariant subspace algorithm (estimation of signal parameters via rotation invariant technology algorithm, ESPRIT), etc.
  • the network device may also determine K angle vectors and L delay vectors by performing DFT on the space-frequency matrix determined based on the uplink channel measurement. This application does not limit the specific method for the network device to determine the K angle vectors and L delay vectors.
  • the predefined angle vector set may be, for example, a vector set composed of multiple vectors in the spatial DFT matrix.
  • the pre-defined delay vector set may be, for example, a vector set composed of multiple vectors in the frequency domain DFT matrix.
  • the network device can determine the uplink channel through channel estimation, and then determine the space-frequency matrix H UL of the uplink channel.
  • the dimension of the space-frequency matrix H UL of the uplink channel is kept consistent with the dimension of the space-frequency matrix H DL of the downlink channel.
  • the dimension of the space-frequency matrix of the downlink channel and the relationship with the downlink channel have been described in the foregoing, and the dimension of the space-frequency matrix H UL determined by the uplink channel may be N ⁇ T.
  • the dimensions of the space-frequency matrix H UL of the uplink channel and the calculation formula used to determine the coefficient matrix C UL shown here are only examples, and should not constitute any limitation to this application. Different dimensions are defined for the space-frequency matrix H UL , and the calculation formulas used to determine the coefficient matrix C UL are also different.
  • the network device can determine the stronger K rows from the coefficient matrix C UL.
  • the stronger K rows can be used to determine K angle vectors.
  • the network device can determine the K rows with larger modulus sum of squares according to the magnitude of the square sum of the modulus of each row element in the coefficient matrix C UL.
  • the K rows with a larger sum of squares of the modulus can be used to determine K angle vectors.
  • the positions of the K rows in the coefficient matrix C UL can be used to determine the positions of the K angle vectors in the above-mentioned angle vector set.
  • the row number of the K rows in the coefficient matrix C UL may be the column number of the K angle vectors in the angle vector set. From this, K angle vectors can be determined.
  • the K angle vectors are the angle vectors selected for precoding the downlink reference signal in the angle vector set.
  • the network device can determine the stronger L columns from the coefficient matrix C UL. Each of the stronger L columns can be used to determine the L delay vectors. For example, the network device may determine the L columns with larger modulus sum of squares according to the magnitude of the sum of squares of the modulus of each column element in the coefficient matrix C UL. The L columns with a larger sum of squares of the modulus can be used to determine the L delay vectors. The positions of the L columns in the coefficient matrix C UL can be used for the positions of the L delay vectors in the above-mentioned delay vector set. For example, the column numbers of the L columns in the coefficient matrix C UL may be the column numbers of the L delay vectors in the delay vector set. Therefore, L delay vectors can be determined. The L delay vectors are the delay vectors selected for precoding the downlink reference signal in the set of delay vectors.
  • the network device may also determine the stronger one or more delay vectors according to each of the stronger K rows in the coefficient matrix C UL. For example, if For the kth row among the K rows, the network device may determine one or more elements whose squares are greater than a preset value, for example, L k according to the squares of the squares of the elements.
  • the preset value may be a predefined value, for example. For example, it can be 80% of the sum of squares of the modulus of the elements in this column.
  • the L k elements whose modulus square is greater than the preset value can be used to determine the L k delay vectors.
  • the column in the coefficient matrix C UL where the L k elements whose modulus square is greater than the preset value can be used to determine the positions of the L k delay vectors in the predefined delay vector set.
  • the column number of the L k elements in the coefficient matrix C UL may be the column number of the L k delay vectors in the delay vector set.
  • the total number of delay vectors can be L.
  • the L delay vectors are the selected delay vectors in the set of delay vectors.
  • the network device may also determine one or more stronger angle vectors according to each of the stronger L columns in the coefficient matrix C UL. For example, if For the l th row of the L rows, the network device may determine one or more elements whose modulus square is greater than a preset value, for example, K 1 according to the square of the modulus of each element.
  • the process for the network device to determine the corresponding angle vector for each delay vector is similar to the process of determining the corresponding delay vector based on each angle vector above, and will not be repeated here for brevity.
  • the uplink channel matrix may be estimated by the network device based on pre-received uplink reference signals, such as SRS, or obtained based on data signals after correct decoding, which is not limited in this application.
  • the specific method for the network device to estimate the uplink channel matrix according to the uplink reference signal can refer to the prior art. For brevity, detailed description of the specific method is omitted here. Since in the FDD mode, the angle and delay of the uplink and downlink channels are interchangeable, the K angle vectors and L delay vectors obtained by the uplink channel measurement can be loaded into the downlink reference signal, so that the terminal equipment can be based on the received preamble. Coding the reference signal for downlink channel measurement.
  • the K angle vectors obtained by the uplink channel measurement can also be loaded on the downlink reference signal, or the L delay vectors obtained by the uplink channel measurement can also be loaded on the downlink reference signal.
  • This embodiment mainly describes in detail the case of loading K angle vectors and L delay vectors to the downlink reference signal.
  • K angle vectors and L delay vectors may be predefined, such as defined by a protocol; or, may also be determined by the network device based on one or more previous downlink channel measurement statistics. This application does not limit the acquisition methods of K angle vectors and L delay vectors.
  • the K angle vectors and L delay vectors are not necessarily determined based on uplink channel measurement.
  • the K angle vectors and L delay vectors may be predefined, as defined in the protocol; or, the K angle vectors and L delay vectors may be fed back based on one or more previous downlink channel measurements The results are statistically determined. This application does not limit the determination methods of the K angle vectors and the L delay vectors.
  • the precoding reference signal obtained by the network device precoding the downlink reference signal based on the K angle vectors and the L delay vectors may be transmitted through pre-configured reference signal resources.
  • the downlink reference signal is a CSI-RS
  • the reference signal resource is a CSI-RS resource.
  • the reference signal resource may include multiple frequency domain units, such as N frequency domain units.
  • the precoding reference signal of each transmit port can be carried on N frequency domain units.
  • the N frequency domain units are used to carry precoding reference signals of P transmit ports, for example, frequency division duplexing (FDD), time division duplexing (TDD), and code division multiplexing may be used.
  • FDD frequency division duplexing
  • TDD time division duplexing
  • CDD code division multiplexing
  • step 320 the terminal device generates first indication information, where the first indication information is used to indicate P groups of weighting coefficients corresponding to P transmit ports.
  • the terminal device may perform channel estimation based on the received precoding reference signal, and generate the first indication information based on the estimated channel information.
  • the first indication information may be used to indicate the P sets of weighting coefficients corresponding to the P transmit ports. Wherein, each group of weighting coefficients may include one or more weighting coefficients.
  • the terminal device may feed back the P groups of weighting coefficients corresponding to the P transmitting ports based on the receiving port.
  • each group of weighting coefficients may include one or more weighting coefficients.
  • each set of weighting coefficients may include R'weighting coefficients. 1 ⁇ R' ⁇ R, and R'is an integer.
  • each set of weighting coefficients includes one weighting coefficient.
  • the weighting coefficient can be obtained by weighting the channel information obtained by performing channel estimation based on the precoding reference signals received on the R receiving ports after time domain transformation, or by performing time domain transformation after weighting; it can also be based on R receiving ports.
  • the channel information obtained by channel estimation is obtained by time domain transformation.
  • each group of weighting coefficients may also include R weighting coefficients.
  • the R weighting coefficients correspond to R receiving ports, and each weighting coefficient is obtained after channel information obtained by performing channel estimation based on a precoding reference signal received on a receiving port after time domain transformation.
  • each set of weighting coefficients includes less than R weighting coefficients.
  • the number of receiving ports is multiple (ie, R>1), and one or more of the R'weighting coefficients may be channel information obtained by performing channel estimation based on precoding reference signals received on part of the receiving ports. Weighted after time domain transformation, or time domain transformation after weighting.
  • the terminal device may also feed back P sets of weighting coefficients corresponding to P transmission ports based on the transmission layer.
  • Each group of weighting coefficients may include Z weighting coefficients, corresponding to Z transmission layers. It should be noted that the weighting coefficients corresponding to the Z transmission layers may also be determined based on the result of time domain transformation of channel information obtained by performing channel estimation on the precoding reference signal received by each receiving port. The specific process of how to determine the weighting coefficients of the P group based on the transmission layer will be described in detail later, which is omitted here.
  • p can be any integer value from 0 to P-1, and the terminal device can execute the following process to determine the corresponding to the p-th transmitting port Weighting factor.
  • Step i Perform channel estimation based on the precoding reference signal of the p-th transmit port received on the r-th receive port, and obtain channel information corresponding to N frequency domain units respectively;
  • Step ii Perform a time domain transformation on the channel information corresponding to the N frequency domain units determined in the above step i, and determine the n p and r values of the N values obtained by the time domain transformation as the same as the p The weighting coefficient corresponding to each transmitting port and the r-th receiving port.
  • the value of p is traversed in the range of 0 to P-1, and the above process is repeated to obtain the P sets of weighting coefficients corresponding to the P transmitting ports.
  • the following describes in detail the process of determining the P sets of weighting coefficients corresponding to P transmitting ports when the terminal device feeds back the weighting coefficients based on the receiving port.
  • each set of weighting coefficients may include one weighting coefficient.
  • the precoding reference signal of each transmit port may be carried by N RBs (that is, an example of frequency domain unit).
  • a set of weighting coefficients corresponding to each transmission port may include one weighting coefficient.
  • the first indication information may be used to indicate P weighting coefficients corresponding to P transmit ports.
  • the terminal device can perform channel estimation based on the received precoding reference signal of each transmission port.
  • the dimension of the downlink channel estimated by the terminal device based on the received precoding reference signal may be N ⁇ T.
  • the dimension of the downlink channel received on each RB may be 1 ⁇ T. Since the network equipment pre-encodes the reference signal based on the angle vector and the delay vector, the dimension of each angle vector can be T ⁇ 1. After the reference signal is pre-encoded by the angle vector and the delay vector, the terminal equipment will The dimensions of the downlink channel received on each receiving port and each RB may be 1 ⁇ 1.
  • the downlink channel with a dimension of 1 ⁇ 1 is the channel information obtained by channel estimation based on the precoding reference signal on one RB.
  • the channel information may specifically be a channel estimation value obtained by performing channel estimation based on the received precoding reference signal. It can be understood that the channel estimation value may specifically be equivalent channel information, that is, precoded channel information.
  • the precoding reference signal carried by each RB can correspond to one or more transmit ports, such as the P transmit ports described above .
  • the P transmitting ports may have a one-to-one correspondence with the P angle delay pairs.
  • the precoding reference signal corresponding to the p-th transmission port among the P transmission ports may be based on, for example, the k-th angle vector among the K angle vectors and the l-th time delay among the L delay vectors.
  • the vector is obtained by precoding the reference signal. That is, the p-th transmitting port corresponds to the k-th angle vector and the l-th delay vector.
  • the precoding reference signal corresponding to the p-th transmit port can be used to determine the weighting coefficient of the angle vector formed by the k-th angle vector and the l-th delay vector, that is, it can be used to determine the p-th angle.
  • the weighting factor of the extension Therefore, the above-mentioned weighting coefficient corresponding to the p-th transmitting port is also the weighting coefficient of the p-th angle delay pair.
  • the terminal device may determine the value of the p-th angular delay pair based on the channel estimation value obtained by performing channel estimation on the precoding reference signal received on one receiving port and N RBs. Weighting factor. The weighting coefficient of the p-th angle delay pair may be determined by the N channel estimation values on the N RBs.
  • the channel estimation value obtained is recorded as the channel estimation value obtained by the terminal equipment based on the precoding reference signal of the p-th transmitting port for channel estimation can be recorded as: A total of N channel estimates. It can be seen that the N channel estimation values correspond to N RBs, that is, to N frequency domain units. Therefore, the N channel estimation values can characterize the change of the channel in the frequency domain. Since the N channel estimation values are determined by channel estimation based on the precoding reference signal of the p-th transmitting port, the N channel estimation values are channel estimation values corresponding to the p-th angle delay pair.
  • the dimension of H DL can be T ⁇ N; the angle vector can be K, the length of each angle vector can be T, then the dimension of S can be T ⁇ K; each delay vector can be There are L, the length of each delay vector can be N, and the dimension of F can be N ⁇ L.
  • H DL H S is the real channel after spatial precoding.
  • the dimension may be N ⁇ K.
  • the network device performs frequency domain precoding on the reference signal after spatial domain precoding based on L delay vectors it can be represented by (H DL H S) HF .
  • the dimension may be K ⁇ L.
  • Each element of C DL in the coefficient matrix can be determined by multiplying a row in (H DL H S) H and a column in F respectively.
  • each element in the matrix coefficient C DL can be obtained by multiplying a row of the conjugate transpose of the real channel H DL H S and a column of F.
  • the element in the lth row and kth column in the coefficient matrix C DL is obtained by multiplying the lth row in H and the kth column in F (H DL H S).
  • the element in the lth row and kth column in the coefficient matrix C DL is also the weighting coefficient corresponding to the kth angle vector and the lth delay vector.
  • the number of elements included in each row vector in (H DL H S) H is the same as the number of elements included in each column vector in F.
  • the number of elements included in each row vector in (H DL H S) H and the number of elements included in each column vector in F may both be N.
  • each element in the row vector (such as the nth element, n is traversed from 1 to N) and the corresponding element in the column vector (such as the nth element, n
  • the values traversed from 1 to N) are multiplied and then summed, and the N elements in each row in (H DL H S) H correspond to N frequency domain units (such as RB, subband, etc.).
  • the network device cannot know the correlation between the downlink channel in each frequency domain unit (such as RB) in advance, so the (H DL H S) HF calculation cannot be completed on the network device side, but only the delay
  • the elements in the vector are loaded on each RB of the downlink channel.
  • H DL ' represents the space-frequency matrix determined by the real downlink channel. Since the real channel dimension is R ⁇ T, the dimension of H DL ' is N ⁇ T.
  • the H DL ' may include N row vectors with a dimension of 1 ⁇ T, such as h 0 , h 1 to h N-1 , corresponding to the 0th to N-1th RBs among the N RBs, respectively.
  • the channel estimated by the terminal device based on the precoding reference signal received at a receiving port can be expressed as:
  • the matrix The nth row in can indicate a channel estimation value obtained by performing channel estimation based on the precoding reference signals of multiple ports received on the nth RB.
  • Each row in may include K ⁇ L elements, which may correspond to K ⁇ L ports, or in other words, K ⁇ L angle delay pairs.
  • the precoding reference signal received by the terminal device has gone through the downlink channel, it is possible to learn the correlation between the downlink channel among various RBs, and the foregoing summation operation can be completed. That is, the matrix The elements in each column are summed separately. That is, will The sum of the elements corresponding to the same delay vector and the same angle vector in, can be obtained: (b( ⁇ 0 ) H H DL 'S... b( ⁇ L-1 ) H H DL 'S) H. For each delay vector and each angle vector, or for each transmitting port, the above operation can be understood as summing the channel estimation values on N RBs.
  • the k-th element in the row vector may correspond to the k-th angle vector in the K angle vectors.
  • b ( ⁇ l) H H DL 'S of the k-th element may correspond to the above channel estimation estimate downlink channel obtained y n p based precoded reference signal the p-th port.
  • the coefficient matrix C DL with dimension K ⁇ L can be obtained,
  • the element in the k-th row and the l-th column of the coefficient matrix C DL corresponds to the k-th angle vector and the l-th delay vector, that is, corresponds to the k-th angle vector and the l-th delay vector.
  • the weighting coefficient of the angle delay pair is rearranged (b( ⁇ 1 ) H H DL 'S... b( ⁇ L ) H H DL 'S) H .
  • the terminal device can determine the weighting coefficient corresponding to each angle delay pair obtained by combining the angle vector and the delay vector by summing the channel estimation values of the N RBs.
  • the N RBs are N frequency domain units in the reference signal resource. Because they are distributed on the frequency domain resource of the reference signal resource, it can also be understood as the full band of the reference signal resource.
  • the weighting coefficient corresponding to the p-th angular delay pair can be obtained by accumulating and summing the N channel estimation values corresponding to the p-th angular delay pair.
  • the network device pre-codes the reference signal based on the delay vector, it loads the N different elements in the delay vector on the N RBs corresponding to the same transmit port. Therefore, the channel estimation value obtained by the terminal equipment estimation on each RB may be discontinuous.
  • the recovered downlink channel may also be quite different from the real channel, so it is determined
  • the precoding matrix used for downlink data transmission cannot match the real channel well, thus affecting the system transmission performance.
  • the terminal device may transform the channel in the frequency domain to the time domain by performing time domain transformation on the N channel estimation values, and use the value obtained by the time domain transformation to characterize the p-th angular delay The weighting factor of the pair.
  • the terminal device may perform time domain transformation on the vector constructed by the N channel estimation values.
  • N values can be obtained through time-domain transformation (for convenience of description, hereinafter referred to as time-domain transformation values).
  • the terminal device may feed back a certain value (for example, the n p- th value) of the N time-domain transform values as a weighting coefficient corresponding to the p-th angle delay pair.
  • N time-domain transform values can be fed back as the weighting coefficient corresponding to the angle delay pair.
  • the N channel estimation values are time-domain transformed, such as IFFT, the upper and lower
  • the DC component of the N time-domain transform values obtained (that is, the 0th value of the N time-domain transform values) is exactly equal to the value received on the N frequency-domain units
  • the sum of N channel estimation values estimated by the precoding reference signal Since the N channel estimation values are respectively estimated based on the reference signals received on the N frequency domain units, the cumulative sum of the N channel estimation values can be understood as the frequency domain accumulation of the N frequency domain units Sum.
  • the coefficient fed back by the terminal device for one of the ports can be expressed as for:
  • h n represents the channel estimation value of the nth frequency domain unit
  • the value of l is 1 and 2.
  • the 0th value (ie, the DC component) Na 1 among the N time-domain transform values obtained by IFFT is exactly equal to the cumulative sum based on the N channel estimation values.
  • the vector can represent the channel vector estimated by the precoding reference signal of the p-th transmitting port.
  • This vector can be expressed as: or, in this embodiment, for the convenience of description, the channel vector formed by the N channel estimation values is denoted as
  • the time domain transform includes IFFT or IDFT. Take IFFT as an example, and combine the above with the channel vector Performing IFFT can obtain N time-domain transform values.
  • the terminal device may determine one of the N time-domain transform values as a weighting coefficient corresponding to the p-th angle delay pair.
  • the terminal device may assume n p value of time delay of N transformed values determined as the p-th delay angle for the corresponding weighting coefficients.
  • the weighting coefficient c p corresponding to the p-th angle delay pair obtained by IFFT can be expressed as: That is, the weighting coefficient c k,l corresponding to the k-th angle vector and the l-th delay vector can be expressed as:
  • n p may be predefined, such as a protocol predefined, or it may be determined by the terminal device itself, or may be instructed by a network device, which is not limited in this application. It can be understood that 0 ⁇ n p ⁇ N-1, and n p is an integer.
  • n p is a predefined value.
  • n p is zero.
  • the terminal device may use the 0th value among the N time domain transform values as the weighting coefficient corresponding to the pth angle delay pair.
  • n p being 0 is only a possible implementation manner, which should not constitute any limitation to this application.
  • n p may also be other values, for example, it may be determined in advance according to an empirical value, or pre-defined by a protocol. This application does not limit this.
  • n p is determined by the terminal device.
  • the foregoing first indication information indicates the value of n p.
  • the terminal device may select a maximum value from the N time domain transformation values as the weighting coefficient corresponding to the p-th angle delay pair.
  • n p is determined by the network device.
  • the method further includes: the terminal device receives fourth indication information, where the fourth indication information is used to indicate the value of np.
  • the network device sends the fourth instruction information.
  • the specific process of the terminal device using one of the N time-domain transform values as the weighting coefficient of the p-th angle delay pair may be implemented by filtering, for example.
  • the vector formed by the aforementioned N time-domain transform values is multiplied by the filter coefficient to obtain the weighting coefficient of the p-th angle delay pair.
  • the filter coefficient may include N elements, for example, it may be recorded as a vector with a dimension of 1 ⁇ N, or a vector with a dimension of N ⁇ 1. To facilitate the distinction, the vector composed of N elements in the filter coefficient is called the filter coefficient vector.
  • the N elements included in the filter coefficient may include N-1 zero elements and 1 non-zero element, and the non-zero elements may be the N elements (or in other words, a filter coefficient vector with a dimension of 1 ⁇ N or a filter coefficient vector with a dimension of N ⁇ 1 filter coefficient vector) in the n p- th element.
  • the aforementioned N time-domain transformation values may, for example, constitute a vector with a dimension of N ⁇ 1, or a vector with a dimension of 1 ⁇ N. For easy distinction, for example, it is called a time domain transform vector.
  • the terminal device can multiply the time domain transform vector with dimension N ⁇ 1 by a filter coefficient vector with dimension 1 ⁇ N to the left, or it can also multiply the time domain transform vector with dimension of 1 ⁇ N by one dimension N ⁇ 1 to the right. To obtain the weighting coefficient corresponding to the p-th angle delay pair.
  • the aforementioned N time-domain transformation values may constitute a time-domain transformation vector with a dimension of N ⁇ 1, for example.
  • the filter coefficient vector formed by the filter coefficient can be denoted as [1 0... 0] 1 ⁇ N .
  • filtering the N time-domain transforms can be achieved by multiplying the above-mentioned time-domain transform vector with the dimension of N ⁇ 1 by the filter coefficient vector [1 0... 0] 1 ⁇ N to the left.
  • the 0th value among the N time-domain transform values can be obtained.
  • filter coefficients listed here are only one possible form, and should not constitute any limitation to this application. Since the specific process of filtering can refer to the prior art, for the sake of brevity, examples are not described here. It should also be understood that filtering is only one possible implementation, and should not constitute any limitation to this application. This application does not limit the specific implementation manner in which the terminal device selects a certain value from the N time-domain transformation values.
  • the terminal device may determine a set of weighting coefficients corresponding to the p-th transmitting port based on the precoding reference signal of the p-th transmitting port received on each receiving port and each RB.
  • the R weighting coefficients may correspond to R receiving ports.
  • the r-th weighting coefficient may be determined based on the precoding reference signal of the r-th receiving port and the p-th transmitting port received on the N RBs.
  • r can take any integer value from 0 to R-1.
  • the terminal device can determine a weighting coefficient according to the method described above.
  • R weighting coefficients corresponding to the p-th transmitting port and R receiving ports can be obtained.
  • the terminal device may determine the n p,r- th value among the N time-domain transformation values to be the same as the r-th receiving port and the p-th transmitting port.
  • the corresponding weighting coefficient is the rth coefficient in the corresponding weighting coefficient of the p-th angle delay pair.
  • the method further comprises: channel information between the p-th transmit-ports with r th receiving ports determined vector time domain transform vector after been transformed, the vector of the n-p, r pieces The value is the r-th weighting coefficient in the p-th group of weighting coefficients.
  • the specific implementation of the terminal device using one of the N time-domain transform values as the weighting coefficient of the p-th angle delay pair can be implemented, for example, through filtering.
  • R>1 for any value of r, the terminal device can multiply the vector formed by the N time-domain transform values corresponding to the r-th receiving port and the p-th transmitting port by the filter coefficient to obtain the first value.
  • a weighting coefficient of p angle delay pairs, and the weighting coefficient may correspond to the r-th receiving port.
  • the filter coefficient may include N elements, for example, it may be recorded as a vector with a dimension of 1 ⁇ N, or a vector with a dimension of N ⁇ 1. Corresponding to the above, this vector can be called a filter coefficient vector.
  • the N elements included in the filter coefficient may include N-1 zero elements and 1 non-zero element, and the non-zero elements may be the N elements (or a filter coefficient vector or a dimension of 1 ⁇ N). Is the n p, rth element in the N ⁇ 1 filter coefficient vector).
  • the terminal device may determine the weighting coefficients corresponding to the r-th receiving port and the p-th transmitting port based on the same manner as described above. Traverse the value of r in the range of 0 to R-1, and then R weighting coefficients corresponding to R receiving ports and p-th transmitting port can be obtained, that is, a set of weighting coefficients corresponding to p-th transmitting port .
  • filtering is only one possible implementation, and should not constitute any limitation to this application. This application does not limit the specific implementation manner in which the terminal device selects a certain value from the N time-domain transformation values.
  • n p and r may be the same or different. This application does not limit this.
  • n p and r are both 0. That is, the 0th value among the N time domain transform values corresponding to the rth receiving port and the pth transmitting port is used as the weighting coefficient corresponding to the rth receiving port and the pth transmitting port.
  • n p,r please refer to the relevant description of n p above. For the sake of brevity, it will not be repeated here.
  • the number of weighting coefficients corresponding to each transmitting port is not necessarily the same as the number of receiving ports.
  • R ⁇ 1 there can be R'weighting coefficients corresponding to each transmitting port, and 1 ⁇ R' ⁇ R. That is to say, when R>1, the weighting coefficients corresponding to each transmitting port may be R or less than R.
  • the terminal device may only perform channel estimation on the precoding reference signal received on a part of the receiving port to determine the weighting coefficient corresponding to the part of the receiving port.
  • the terminal device is configured with 2 receiving ports.
  • the terminal device only performs channel estimation on the precoding reference signal received on one of the receiving ports.
  • the terminal device can estimate N channel estimation values based on the precoding reference signal of each (for example, the p-th) transmitting port received on the receiving port, and the N channel estimation values can be obtained after time domain transformation.
  • the protocol may predefine some rules so that the terminal device can determine the weighting coefficient to be reported based on the precoding reference signal received on which receiving port.
  • the protocol may also predefine the terminal device or the network device may notify the terminal device in advance through signaling to determine the weighting coefficient based on the precoding reference signal received on which receiving port.
  • the terminal device may decide on its own to determine the weighting coefficient based on the precoded signal received on which receiving port. This application does not limit this.
  • the terminal device may also weight the channel estimation value obtained by performing channel estimation based on the precoding reference signals received on multiple receiving ports, and perform a time domain transformation on the weighted value; or, it may also be based on The precoding reference signal received on each receiving port of the multiple receiving ports is respectively subjected to channel estimation.
  • the channel estimation value obtained by the time domain transformation is weighted and summed, so that the values corresponding to one transmitting port and multiple receiving ports are summed.
  • the weighting coefficients are weighted, and the number of weighting coefficients corresponding to each transmitting port is less than the number R of receiving ports.
  • the terminal device is configured with 4 receiving ports.
  • the terminal device can weight the channel estimation value obtained by performing channel estimation based on the precoding reference signal received on each of the two receiving ports, and perform the time domain transformation on the weighted value, so as to obtain the corresponding one (for example, the first p) 2 weighting coefficients of the transmitting port; alternatively, the terminal device may perform time-domain transformation on the channel estimation value obtained by performing channel estimation based on the precoding reference signal received on each of the 4 receiving ports to The values corresponding to the four receiving ports are obtained, and then the values corresponding to each two receiving ports are weighted and summed, so that two weighting coefficients corresponding to one (for example, the p-th) transmitting port can be obtained.
  • the terminal device can determine a set of weighting coefficients corresponding to each of the P transmission ports.
  • the terminal device may generate the first indication information based on the determined weighting coefficient corresponding to each transmission port.
  • a matrix with a dimension of P ⁇ R' may be constructed.
  • the matrix constructed by the P groups of weighting coefficients is called a coefficient matrix.
  • Each row in the coefficient matrix may correspond to a transmission port.
  • the following shows an example of a coefficient matrix with a dimension of P ⁇ R constructed from P sets of weighting coefficients corresponding to P transmission ports.
  • the coefficients c p,r in the coefficient matrix can represent the p-th transmitting port (or the p-th angle delay pair, corresponding to the k-th angle vector and the l-th delay vector), the r-th receiving port The weighting factor corresponding to the port.
  • the value of the P group of weighting coefficients by the terminal device may be indicated by a quantized value, an index of a quantized value, or other forms, for example.
  • the terminal device may perform normalization processing on the P group of weighting coefficients, and generate the first indication information based on the result of the normalization processing.
  • the so-called normalization process is the process of controlling the amplitude value of all weighting coefficients within the range of not exceeding 1 within the range of the normalization unit.
  • the terminal device may determine the weighting coefficient with the largest amplitude from the P group of weighting coefficients (for the convenience of distinction and description, for example, the amplitude of the weighting coefficient is recorded as the largest amplitude).
  • the terminal device may divide the amplitudes of the weighting coefficients other than the weighting coefficient by the maximum amplitude to obtain the ratio corresponding to each weighting coefficient.
  • the terminal device normalizes the P group of weighting coefficients, the above-mentioned maximum amplitude is normalized to 1, and the remaining weighting coefficients are respectively corresponding ratios.
  • the terminal device may generate the first indication information based on the quantized value or the non-quantized value of each normalized result.
  • the normalization unit may also be a transmitting port, that is, each row in the above-mentioned coefficient matrix is normalized separately. This application does not limit the normalized unit.
  • the network device can be configured with J polarization directions, J ⁇ 1.
  • the terminal device can perform channel estimation based on the precoding reference signal of the transmitting port in each polarization direction according to the method described above, and obtain the weighting coefficient corresponding to each transmitting port in each polarization direction.
  • the first P rows in the coefficient matrix correspond to the P transmit ports in the first polarization direction.
  • the weighting coefficients in the first P row are the P groups of weighting coefficients corresponding to the P transmitting ports in the first polarization direction.
  • the last P rows in the coefficient matrix correspond to P transmit ports in the second polarization direction.
  • the weighting coefficients in the last P row are P sets of weighting coefficients corresponding to the P transmitting ports in the second polarization direction.
  • the terminal device does not necessarily generate the aforementioned coefficient matrix.
  • the terminal device when the terminal device indicates the weighting coefficients corresponding to the transmitting ports in multiple polarization directions, for example, they may indicate them sequentially in a predetermined order.
  • the terminal device may perform normalization processing on the weighting coefficients corresponding to each transmitting port in the first polarization direction and the weighting coefficients corresponding to each transmitting port in the second polarization direction respectively, and generate the second wave based on the result of the normalization processing.
  • the first indication information may include information used to indicate weighting coefficients corresponding to each transmitting port in the first polarization direction and information used to indicate weighting coefficients corresponding to each transmitting port in the second polarization direction.
  • the normalized unit may be P transmit ports in one polarization direction.
  • the terminal device may also perform normalization processing on the weighting coefficients corresponding to each transmitting port in the two polarization directions, and generate the first indication information based on the result of the normalization processing.
  • the normalized unit can be 2P transmit ports in two polarization directions.
  • this application does not limit the order in which the terminal device indicates the weighting coefficients. As long as the network device can recover the weighting coefficients corresponding to the transmission ports in the J polarization directions according to the first indication information.
  • the terminal device indicates the weighting coefficient corresponding to each transmission port in each polarization direction through the first indication information, it does not necessarily mean that the first indication information includes an indication of all the weighting coefficients. As long as the network device can determine all the weighting coefficients according to the first indication information, it can be considered that the first indication information is used to indicate all the weighting coefficients.
  • the terminal device when the terminal device indicates the weighting coefficients corresponding to P transmitting ports in one polarization direction through the first indication information, such as the P ⁇ R' weighting coefficients mentioned above, it does not necessarily indicate the first
  • the indication information includes an indication of each of the P ⁇ R' weighting coefficients.
  • the terminal device can indicate the position corresponding to the maximum amplitude (such as the corresponding transmitting port and receiving port or the rows and columns in the coefficient matrix) and The ratio of the amplitude of other weighting coefficients to the maximum amplitude, etc. That is, as long as the network device can recover the P ⁇ R' weighting coefficients according to the first indication information, it can be considered that the first indication information is used to indicate the P ⁇ R' weighting coefficients.
  • each transmitting port corresponds to an angle vector and a delay vector, or, in other words, corresponds to an angle delay pair
  • the above-mentioned weighting coefficients are all weighting coefficients corresponding to the angle delay pair.
  • the network device can determine the angle-delay pair corresponding to each weighting coefficient according to the corresponding relationship between each transmitting port and the angle vector and the delay vector.
  • step 330 the terminal device sends the first indication information.
  • the network device receives the first indication information.
  • the first indication information may be, for example, CSI, or part of information elements in the CSI, or other information.
  • the first indication information is a precoding matrix indicator (PMI).
  • PMI precoding matrix indicator
  • the first indication information may be carried in one or more messages in the prior art and sent by the terminal device to the network device, or carried in one or more newly designed messages and sent by the terminal device to the network device.
  • the terminal device may send the first indication information to the network device through physical uplink resources, such as physical uplink share channel (PUSCH) or physical uplink control channel (PUCCH), to facilitate the network device
  • the precoding matrix is determined based on the first indication information.
  • 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 the prior art. For brevity, a detailed description of the specific process is omitted here.
  • each set of weighting coefficients may include one or more weighting coefficients, and each weighting coefficient may correspond to one or more weighting coefficients.
  • the method further includes: the terminal device sends fifth indication information, where the fifth indication information is used to indicate the number R of receiving ports.
  • the network device receives the fifth indication information.
  • the network device can determine the number of weighting coefficients indicated by the first indication information according to the number of receiving ports.
  • the fifth indication information and the foregoing first indication information may be carried in the same signaling, or may be carried in different signaling, which is not limited in this application.
  • the terminal device may also feed back P sets of weighting coefficients corresponding to P transmit ports based on the transmission layer.
  • each set of weighting coefficients may include Z weighting coefficients corresponding to the Z transmission layers.
  • the weighting coefficient corresponding to each transmitting port in the two polarization directions is taken as an example to illustrate the process of the terminal device determining the weighting coefficient based on the transmission layer feedback.
  • a set of weighting coefficients corresponding to each transmitting port determined by the terminal device is R, corresponding to the R receiving ports. Then the weighting coefficient determined by the terminal device based on the receiving port can be expressed by a matrix as:
  • the terminal device may perform SVD on the coefficient matrix to obtain the weighting coefficient based on the transmission layer feedback.
  • the weighting coefficient determined by the terminal device based on the transmission layer can be expressed by a matrix as:
  • Each weighting coefficient in the coefficient matrix is represented by d to distinguish it from the weighting coefficient c based on feedback from the receiving port.
  • the first P row in the coefficient matrix may correspond to the first polarization direction, and the last P row may correspond to the second polarization direction.
  • Z columns correspond to Z transport layers. Therefore, each row in the coefficient matrix can represent a set of weighting coefficients corresponding to a transmitting port in a polarization direction.
  • Each group of weighting coefficients may include Z weighting coefficients, corresponding to Z transmission layers.
  • the weighting coefficients of the p-th row and the z-th column in the first P row represent the weighting coefficients corresponding to the p-th transmit port and the z-th transmission layer in the first polarization direction; the p-th row in the last P row , The weighting coefficient in the z-th column represents the weighting coefficient corresponding to the p-th transmitting port and the z-th transmission layer in the second polarization direction.
  • the P group of weighting coefficients corresponding to the P transmitting ports determined by the terminal device based on the receiving port can determine the P group of weighting coefficients corresponding to the P transmitting ports based on the feedback of the transmission layer. It has been explained above that the P sets of weighting coefficients corresponding to the P transmitting ports determined based on the receiving port are obtained based on the above-mentioned time domain transformation method. Therefore, in the embodiment of the present application, whether it is based on the receiving port to feed back the P group of weighting coefficients or the transmission layer is based on the feedback of the P group of weighting coefficients. The determination of each weighting coefficient by the terminal device can be obtained by the above-mentioned time domain transformation method.
  • the terminal device may generate the first indication information based on the foregoing P sets of weighting coefficients corresponding to the P transmit ports in each polarization direction, so as to indicate through the first indication information the information corresponding to the P transmit ports in each polarization direction.
  • P group weighting coefficient The specific method for the terminal device to indicate the weighting coefficients based on the transmission layer feedback through the first indication information is similar to the specific method for indicating the P groups of weighting coefficients corresponding to the P transmitting ports based on the receiving port feedback through the first indication information described above, For example, the weighting coefficient can be normalized. Since the specific process of the terminal device indicating the weighting coefficient based on the receiving port feedback through the first indication information has been described in detail above, for the sake of brevity, it will not be repeated here.
  • the method further includes: the terminal device sends sixth indication information, where the sixth indication information is used to indicate the number Z of transmission layers.
  • the network device receives the sixth indication information.
  • the sixth indication information may be carried in the same signaling as the above-mentioned first indication information, or may also be carried in different signaling.
  • the fifth indication information is rank indication (rank indication, RI). It should be understood that this application does not limit the specific signaling used to carry the sixth indication information.
  • step 340 the network device determines a precoding matrix according to the first indication information.
  • the terminal device may feed back the P group of weighting coefficients corresponding to the P transmission ports based on the receiving port, and may also feed back the P group of weighting coefficients corresponding to the P transmission ports based on the transmission layer.
  • the network device may determine the precoding matrix according to the first indication information based on different feedback granularities.
  • the weighting coefficient indicated by the first indication information may include the weighting coefficients corresponding to one or more receiving ports.
  • the network device may reconstruct the downlink channel based on the weighting coefficient indicated by the first indication information and the angle-delay pair corresponding to each weighting coefficient, and then determine the precoding matrix of each frequency domain unit.
  • each group of weighting coefficients in the P groups of weighting coefficients fed back by the terminal device includes R weighting coefficients corresponding to R receiving ports.
  • the P weighting coefficients corresponding to each receiving port may correspond to the P angle delays in a one-to-one correspondence.
  • the network device can construct a corresponding to each receiving port based on the P weighting coefficients corresponding to each receiving port of the terminal device, and the angle vector and the delay vector contained in each angle delay pair in the P angle delay pairs Space frequency matrix.
  • the space-frequency matrix corresponding to the receiving port is denoted as H DL,R . Indicates the space-frequency matrix corresponding to the r-th receiving port, and r can take any integer value from 0 to R-1.
  • the space-frequency matrix corresponding to the r-th receiving port may be determined by P angle delay pairs and P weighting coefficients corresponding to the r-th receiving port.
  • P angle delay pairs can be used to construct P space-frequency component matrices.
  • the k-th angle vector a( ⁇ k ) among the K angle vectors and the l-th delay vector b( ⁇ l ) among the L delay vectors can construct the space-frequency component matrix a( ⁇ k ) ⁇ b( ⁇ l ) H.
  • Space-frequency matrix corresponding to the r-th receiving port It can be a weighted sum of P space-frequency component matrices. which is, Represents the weighting coefficient corresponding to the k-th angle vector and the l-th delay vector based on the feedback of the r-th receiving port.
  • the dimension of the space-frequency matrix may be T ⁇ N.
  • the specific process of determining the space-frequency matrix corresponding to the receiving port is described by taking one polarization direction of the transmitting antenna as an example. But this should not constitute any limitation to this application.
  • the network device can still determine the space frequency matrix corresponding to each receiving port based on the method described above.
  • the space-frequency matrix corresponding to the r-th receiving port can be determined by the following formula:
  • the space-frequency matrix defined above for the two polarization directions The calculation formula of is only an example, and should not constitute any limitation to this application.
  • the number of delay vectors and/or angle vectors loaded in different polarization directions may be the same or different, and the delay vectors and/or angle vectors loaded in different polarization directions may be the same or different .
  • the network device can determine the space-frequency matrix based on the P weighting coefficients corresponding to each receiving port. to Thus, the network device can determine the downlink channel matrix corresponding to each frequency domain unit.
  • the network device may determine the conjugate transpose (V (n) ) H of the downlink channel matrix corresponding to the nth RB.
  • the matrix (V (n) ) H can be the R space-frequency matrices respectively determined based on the R receiving ports. to The nth column vector in each space-frequency matrix is determined. For example, change The nth column in the matrix (V (n) ) H is the 0th column, and The nth column in the matrix (V (n) ) H is the first column; and so on, you can The nth column in the matrix (V (n) ) H is the R-1th column. From this, the matrix (V (n) ) H can be obtained, and then the downlink channel matrix V (n) corresponding to the nth RB can be determined.
  • the downlink channel matrix corresponding to each RB can be determined.
  • the network device may further determine the precoding matrix of each RB according to the downlink channel matrix of each RB. For example, the network device can determine the precoding matrix by performing SVD on the downlink channel matrix or the covariance matrix of the channel matrix, or it can also perform eigenvalue decomposition (eigenvalue decomposition, EVD) on the covariance matrix of the downlink channel matrix. The way is ok.
  • eigenvalue decomposition eigenvalue decomposition
  • the specific manner for the network device to determine the precoding matrix according to the channel matrix may refer to the prior art, and this application does not limit the manner for determining the precoding matrix.
  • the network device determines the downlink channel matrix based on the space-frequency matrix, and then determines the precoding matrix. But this should not constitute any limitation to this application.
  • the network device can also directly determine the precoding matrix according to the space frequency matrix.
  • the terminal device corresponds to one receiving port based on each weighting coefficient in the P group of weighting coefficients.
  • the number of weighting coefficients in each group is not necessarily equal to the number of receiving ports.
  • the number of receiving ports is greater than 1, but the terminal device only performs channel estimation and feedback based on the precoding reference signal received on one of the receiving ports.
  • Each set of weighting coefficients may include only one weighting coefficient.
  • the network device may regard the weighting coefficient fed back based on the receiving port as the weighting coefficient of each receiving port, and then determine the precoding matrix according to the method described above.
  • the terminal device weights the channel estimation values of multiple receiving ports and performs time-domain transformation and feedback.
  • the number of weighting coefficients included in each group of weighting coefficients is less than the number of receiving ports.
  • the network device may regard the weighting coefficients fed back based on the multiple receiving ports as the weighting coefficients of the multiple receiving ports, and then determine the precoding matrix according to the method described above. This application does not limit the specific manner in which the network device determines the precoding matrix based on the received weighting coefficient.
  • the weighting coefficient indicated by the first indication information may include one or more transmission layer weighting coefficients.
  • the network device may determine the space-frequency matrix corresponding to the transmission layer based on the weighting coefficient corresponding to each transmission layer and the angle delay pair corresponding to each weighting coefficient, and then determine the precoding matrix of each frequency domain unit.
  • the network device may construct a space-frequency matrix corresponding to the transmission layer based on the P weighting coefficients corresponding to each transmission layer, and the angle vector and the delay vector included in each angle delay pair in the P angle delay pairs.
  • the space-frequency matrix corresponding to the receiving port is denoted as H DL,Z .
  • the space-frequency matrix corresponding to the z-th transmission layer It can be determined by P angle delay pairs and P weighting coefficients corresponding to the z-th transmission layer.
  • P angle delay pairs can be used to construct P space-frequency component matrices.
  • the precoding vector corresponding to the z-th transmission layer may be a weighted sum of P space-frequency component matrices. which is, Represents the weighting coefficient corresponding to the k-th angle vector and the l-th delay vector based on the feedback of the r-th receiving port.
  • the dimension of the space-frequency matrix may be T ⁇ N.
  • the specific process of determining the space-frequency matrix corresponding to the receiving port is described by taking one polarization direction of the transmitting antenna as an example. But this should not constitute any limitation to this application.
  • the network device can still determine the space frequency matrix corresponding to each receiving port based on the method described above.
  • the space-frequency matrix corresponding to the r-th receiving port can be determined by the following formula:
  • the space-frequency matrix defined above for 2 polarization directions The calculation formula of is only an example, and should not constitute any limitation to this application.
  • the number of delay vectors and/or angle vectors loaded in different polarization directions may be the same or different, and the delay vectors and/or angle vectors loaded in different polarization directions may be the same or different .
  • the network device can determine the space-frequency matrix corresponding to each transmission layer based on the P weighting coefficients corresponding to each transmission layer. to Thus, the network device can determine the precoding matrix W (n) corresponding to each RB.
  • the network device may determine the conjugate transpose (V (n) ) H of the downlink channel matrix corresponding to the nth RB.
  • the matrix (V (n) ) H can be the R space-frequency matrices respectively determined based on the R receiving ports. to The nth column vector in each space-frequency matrix is determined.
  • the precoding matrix W(n) corresponding to the nth RB may be the Z space-frequency matrices respectively determined based on the Z transmission layers. to The nth column vector in each space-frequency matrix is constructed. For example, change The nth column in W (n) is the 0th column of the downlink channel matrix W (n), and The nth column in W(n) is the first column of the downlink channel matrix W (n); and so on, you can The nth column in W(n) is the Z-1th column of the downlink channel matrix W (n). Based on the above method, the precoding matrix corresponding to each RB can be determined.
  • the network device may also determine P space-frequency component vectors based on P angle delay pairs, and then determine the precoding matrix.
  • P space-frequency component vectors based on P angle delay pairs
  • the process of determining the precoding matrix corresponding to each frequency domain unit described above is described by taking RB as an example of the frequency domain unit. Therefore, the determined downlink channel is the downlink channel corresponding to the RB, and the determined precoding matrix is the precoding matrix corresponding to the RB.
  • the precoding matrix corresponding to the RB may refer to the precoding matrix determined based on the channel matrix corresponding to the RB with the granularity of the RB, or in other words, the precoding matrix determined based on the precoding reference signal received on the RB, which can be used for Precoding the data transmitted through the RB.
  • the downlink channel corresponding to the RB may refer to a downlink channel determined based on the precoding reference signal received on the RB, which may be used to determine the precoding matrix corresponding to the RB.
  • the network device may determine the precoding matrix of the frequency domain unit according to the precoding matrix corresponding to each RB in each frequency domain unit.
  • each frequency domain unit includes an RB for carrying a reference signal
  • the network device may use the precoding matrix corresponding to the RB as the precoding matrix corresponding to the frequency domain unit to which it belongs. If each frequency domain unit includes multiple RBs for carrying reference signals, the network device may, for example, average the correlation matrices of the precoding matrices corresponding to the multiple RBs in the same frequency domain unit and perform SVD to determine the frequency.
  • the precoding matrix corresponding to the domain unit for example, the network device may use the average of the precoding matrixes corresponding to multiple RBs in the same frequency domain unit as the precoding matrix corresponding to the frequency domain unit, and so on.
  • the specific method for the network device to determine the precoding matrix of the frequency domain unit according to the precoding matrix corresponding to the multiple RBs in the frequency domain unit can refer to the technology, and is not limited to the above-listed. This application does not limit the specific method for determining the precoding matrix of the frequency domain unit by the precoding matrixes corresponding to multiple RBs in the frequency domain unit of the network device.
  • the weighting coefficient corresponding to a certain angle vector and a certain time delay vector mentioned in the above description that is, the weighting coefficient corresponding to the angle delay pair formed by a certain angle vector and a certain time delay vector .
  • the weighting coefficient corresponding to the k-th angle vector and the l-th delay vector that is, the weighting coefficient corresponding to the angle-delay pair formed by the k-th angle vector and the l-th delay vector.
  • I will not illustrate them one by one here.
  • the network device may, for example, precode the downlink reference signal based on the angle and time delay determined by the uplink channel measurement, so that the terminal device performs downlink channel measurement according to the precoded reference signal. Since the network equipment precodes the reference signal based on the reciprocal angle and time delay of the uplink and downlink channels, the information of the downlink channel detected by the terminal equipment is non-reciprocal information. Therefore, the terminal device may not need to feed back spatial and frequency domain vectors (such as the above-mentioned angle vector and delay vector), which greatly reduces the feedback overhead of the terminal device.
  • the frequency domain channel by converting the frequency domain channel to the time domain, the value obtained by the time domain transformation is fed back as the weighting coefficient, and the weighting coefficient is restored based on the weighting coefficient obtained by the frequency domain accumulation and summation of multiple discontinuous equivalent channels.
  • the problem of channel inaccuracy can be avoided, which is beneficial to improve the transmission performance of the system. Therefore, while reducing the feedback overhead, higher feedback accuracy can still be ensured.
  • the number of ports of the reference signal can be reduced, thereby reducing the pilot overhead.
  • the embodiments of the present application are only for ease of understanding, and show the specific process of downlink channel measurement and determination of the precoding matrix when the space-frequency matrix is obtained by the conjugate transposition of the real channel. But this should not constitute any limitation to this application.
  • the relationship between the real channel and the space-frequency matrix H DL is not fixed. Different definitions of the space-frequency matrix and the space-frequency component matrix may change the relationship between the real channel and the space-frequency matrix H DL.
  • the space-frequency matrix H DL can be obtained by the conjugate transposition of the real channel, or can be obtained by the transposition of the real channel.
  • precoding the reference signal based on the angle vector and the delay vector is taken as an example to describe the channel measurement method provided in this application in detail. But this should not constitute any limitation to this application.
  • the network device may also pre-encode the reference signal based only on the delay vector or the angle vector, so that the terminal device can perform downlink channel measurement based on the pre-encoded reference signal.
  • the following embodiment takes precoding of the reference signal based only on the delay vector as an example to describe in detail the channel measurement method provided by this application.
  • FIG. 4 is a schematic flowchart of a channel measurement method 400 provided by another embodiment of the present application from the perspective of device interaction.
  • the method 400 shown in FIG. 4 may include step 410 to step 440.
  • the steps in the method 400 are described in detail below.
  • the transmitting antenna of one polarization direction may be any one of the transmitting antennas of the J polarization directions configured by the network device. This application does not limit the number J of polarization directions of the transmitting antennas configured by the network equipment.
  • step 410 the terminal device receives the precoding reference signal.
  • the network device sends the precoding reference signal.
  • the network device may precode the reference signal based on the L delay vectors, which may specifically refer to frequency domain precoding. Since the reference signal has not undergone spatial precoding, before the reference signal is precoded based on the delay vector, the reference signal may correspond to T transmit antenna ports.
  • the reference signal is pre-coded based on the L delay vectors, and the obtained pre-coded reference signal may correspond to L groups of ports.
  • Each group of ports may correspond to a precoding reference signal obtained by precoding the reference signals of the T transmit antenna ports based on the same delay vector.
  • Each group of ports may include a maximum of T ports, and the T ports may correspond to the above T transmitting antenna ports. Therefore, the precoding reference signal of each port can correspond to a delay vector and a transmitting antenna port. In other words, each port can be a combination of a delay vector and a transmitting antenna port.
  • the network device can traverse L delay vectors and precode the reference signal on each transmit antenna port.
  • T ⁇ L different combinations, or T ⁇ L antenna delay pairs can be obtained. Since the angle vector used for spatial precoding is not involved, each combination can correspond to a delay vector. In other words, by loading L delay vectors on the reference signals of different transmit antenna ports, a total of T ⁇ L combinations of delay vectors and different transmit antenna ports can be obtained.
  • the network device can traverse the L delay vectors, and based on one or more delay vectors in the L delay vectors, the network equipment can be used for part of the frequency domain units carried in the N frequency domain units.
  • the above reference signal is pre-coded, and the pre-coded reference signal is transmitted through T transmit antenna ports.
  • the precoding reference signals obtained by precoding based on different delay vectors can be mapped to different frequency domain units.
  • the precoding reference signal carried on each frequency domain unit may be obtained by precoding based on partial delay vectors among the L delay vectors.
  • at least two precoding reference signals carried by frequency domain units are obtained by precoding based on different delay vectors. In other words, by loading L delay vectors on different frequency domain units and sending them through T transmit antenna ports, a total of T ⁇ L' different combinations of delay vectors and transmit antenna ports can be obtained, 1 ⁇ L' ⁇ L, L'is an integer.
  • the number of ports of the transmitted precoding reference signal may be the number of combinations determined by the T transmit antenna ports and the L delay vectors.
  • the number of transmission ports is recorded as L groups, and each group of transmission ports may include a delay vector and one or more transmission antenna ports corresponding to the delay vector.
  • each group of transmitting ports includes T transmitting ports. That is, the L delay vectors can be shared for each transmit antenna port.
  • the above L delay vectors can all be determined based on uplink channel measurement. Since the above method 300 has described in detail the specific method for the network device to determine the L strong delays based on the uplink channel measurement, for the sake of brevity, it will not be repeated here.
  • the L delay vectors based on the uplink channel measurement is not the only implementation method.
  • the L delay vectors may be predefined, such as defined by the protocol; or, may also be based on one or more previous downlink channels.
  • the results of measurement and feedback are statistically determined. This application does not limit this.
  • the L delay vectors obtained from the uplink channel measurement can be loaded into the downlink reference signal, so that the terminal device can perform downlink channel measurement based on the received precoding reference signal .
  • the network device may pre-code the downlink reference signal, such as CSI-RS, based on the L delay vectors to obtain the pre-coded reference signal.
  • the network device may transmit the precoding reference signal through a pre-configured reference signal resource. Because the process of precoding the reference signal based on the delay vector has been described in detail above in conjunction with FIG. 2, and the method 300 has described in detail the method used to distinguish different transmission ports when the network device transmits the precoding reference signal through the reference signal resource. For the sake of brevity, I won’t repeat it here.
  • step 420 the terminal device generates seventh indication information, which is used to indicate P sets of weighting coefficients corresponding to P angle delay pairs.
  • the terminal device may perform channel estimation based on the received precoding reference signal, and generate seventh indication information based on the estimated channel information.
  • the seventh indication information may be used to indicate P sets of weighting coefficients corresponding to P angle delay pairs. Wherein, each group of weighting coefficients may include one or more weighting coefficients.
  • the P angle delay pairs may be obtained by combining the above L delay vectors and K angle vectors.
  • the K angle vectors can be combined with the aforementioned L delay vectors to obtain P angle delay pairs, and the weight of the P angle delay pairs can be used to construct a precoding matrix.
  • the K angle vectors may be notified by the network device to the terminal device through signaling in advance, or may be determined by the terminal device itself.
  • the network device may indicate the angle-related information to the terminal device through signaling in advance.
  • the network device can indicate the angle-related information.
  • the network device can indicate the angle vector corresponding to each of the L delay vectors to the terminal device through signaling according to the measurement result of the uplink channel; for another example, the network device can indicate the relationship with the L time delay vectors through signaling.
  • the angle corresponding to each delay vector in the delay vector so that the terminal device can determine the angle vector corresponding to each delay vector; for example, the network device can indicate that it corresponds to each delay vector in the L delay vectors through signaling
  • One of the angles for the convenience of distinction and description, recorded as the reference angle
  • the difference or ratio of other angles to the reference angle etc.
  • I will not illustrate them one by one.
  • the angle vectors corresponding to any two of the L delay vectors are the same, it can be considered that the L delay vectors correspond to the same K angle vectors, or in other words, the K The angle vector can be considered to be common to each delay vector.
  • the terminal device may determine K angle vectors based on one or more previous downlink channel measurement statistics.
  • the terminal device may feed back P sets of weighting coefficients corresponding to P angle delay pairs based on the receiving port.
  • each set of weighting coefficients may include one or more weighting coefficients.
  • each set of weighting coefficients may include R'weighting coefficients. 1 ⁇ R' ⁇ R, and R'is an integer.
  • the following first describes the process of determining the P sets of weighting coefficients corresponding to P angle delay pairs when the terminal device determines the weighting coefficients based on the receiving port.
  • each set of weighting coefficients may include one weighting coefficient.
  • the precoding reference signal of each group of transmit ports may be carried by N RBs (that is, an example of frequency domain unit).
  • a group of weighting coefficients corresponding to each group of transmitting ports may include one weighting coefficient.
  • the seventh indication information can be used to indicate the L weighting coefficients corresponding to the L groups of transmit ports.
  • the terminal device can perform channel estimation based on each group of transmission ports.
  • the weighting coefficient corresponding to each transmitting port can be estimated from the channel of N RBs. The values are accumulated and summed.
  • the terminal device After receiving the precoding reference signal from the network device, the terminal device can perform channel estimation on each RB.
  • the estimated channel information can be processed according to the predetermined angle vector corresponding to each delay vector to determine a set of weighting coefficients corresponding to each angle delay pair.
  • the real channel received by the terminal device can be expressed as F H H DL H , and its dimension can be L ⁇ T.
  • Each element of the coefficient matrix C DL can be represented by the real channel after the frequency-domain precoding F H H DL H conjugate transpose (F H H DL H) H S H multiplying obtained.
  • the number of each column vector (F H H DL H) H time-multiplied S H, (F H H DL H) H includes elements of each row vector S H included
  • the number of elements is the same.
  • the number and the number of elements in each column vector S H (F H H DL H) H in each row included in the vector may comprise elements of both T.
  • the terminal device loads the angle vector to the channel estimation value on each RB, and then sums the channel estimation value on the N RBs obtained by loading the same angle vector, it can obtain the sum of an angle vector and a delay vector (I.e., a pair of angular delay) corresponding weighting coefficient.
  • a delay vector I.e., a pair of angular delay
  • the precoding reference signal carried on the RB can correspond to L ⁇ T transmissions.
  • Port or in other words, L group launch port.
  • Each group of ports includes T transmit ports.
  • Each group of transmit ports corresponds to one of the L delay vectors.
  • the terminal device may determine the weighting coefficient corresponding to each angle delay pair based on the channel information estimated by the precoding reference signal of each group of transmission ports received on a receiving port.
  • the terminal device may determine the channel information corresponding to each group of transmission ports on the nth RB according to the precoding reference signal corresponding to the same group of transmission ports received on the nth RB among the N RBs.
  • the estimated channel information can be a vector with a dimension of 1 ⁇ T, for example, denoted as
  • the nth RB is connected to the kth angle vector and the lth angle vector.
  • the channel information of the angle delay pair formed by the delay vectors can be expressed as
  • the delay angle of the n-th on the RB k, and l-th delay vectors and K l l vector angles angular configuration vector may be expressed as
  • the terminal device can determine the channel information corresponding to a delay vector and an angle vector on each RB of the N RBs, or in other words, the channel information corresponding to one angle delay pair on each RB.
  • the precoding reference signal received by the terminal device is a reference signal pre-coded based on a time domain vector
  • the equivalent channel received by the terminal device is not continuous in the frequency domain. Therefore, the channel information corresponding to the same angle delay pair on each RB determined based on the above method is not accurate. If the channel information corresponding to the same angle delay pair on N RBs is directly accumulated and summed, the result is not accurate. In this embodiment, time-domain transformation can still be used to obtain more accurate weighting coefficients.
  • the terminal device may perform time domain transformation on the channel information on the N RBs corresponding to the same angular delay pair to obtain the transformed N values.
  • the n p value of the N values may be used as a weighting coefficient corresponding to the p angle delay pair.
  • the terminal device may obtain the weighting coefficient corresponding to each angle delay pair by means of time domain filtering.
  • time domain filtering The specific process of time-domain filtering has been described in detail in step 320 of the method 300 above, and for the sake of brevity, it will not be repeated here.
  • the terminal device can determine the P sets of weighting coefficients corresponding to the P angle delay pairs combined with the L delay vectors and the K angle vectors.
  • Each group of weighting coefficients may include R'weighting coefficients, 1 ⁇ R' ⁇ R, and R'is an integer.
  • the weighting coefficient in each group may correspond to one or more of the R receiving ports. It should be understood that the process of determining each of the R'weighting coefficients by the terminal device can refer to the method described above, and for brevity, it will not be repeated here.
  • the terminal device may also feed back P sets of weighting coefficients corresponding to the P angle delay pairs based on the transmission layer.
  • the terminal device determines the P set of weighting coefficients corresponding to the P transmit ports based on the transmission layer feedback according to the P set of weighting coefficients corresponding to the P transmit ports determined based on the receiving antenna.
  • the terminal device may determine the P sets of weighting coefficients corresponding to the P transmit ports in each polarization direction based on the same method described above.
  • the specific process for the terminal device to generate the seventh indication information based on the determined weighting coefficient may refer to the specific process for the terminal device to generate the first indication information in step 330 in the method 300 above. For the sake of brevity, I won't repeat them here.
  • step 430 the terminal device sends the seventh indication information.
  • the network device receives the seventh indication information.
  • step 440 the network device determines a precoding matrix according to the seventh indication information.
  • step 430 to step 440 may be the same as the specific process from step 330 to step 340 in the method 300 above.
  • step 430 to step 440 reference may be made to the related description of step 330 to step 340 in the method 300 above. For brevity, it will not be repeated here.
  • the network device precodes the downlink reference signal based on the angle and time delay determined by the uplink channel measurement, so that the terminal device performs downlink channel measurement according to the precoded reference signal. Since the network device precodes the reference signal based on the reciprocal delay of the uplink and downlink channels, the information of the downlink channel detected by the terminal device is non-reciprocal information. Therefore, the terminal device may not need to feed back spatial and frequency domain vectors (such as the above-mentioned angle vector and delay vector), which greatly reduces the feedback overhead of the terminal device.
  • the frequency domain channel is converted to the time domain, the value obtained by the time domain transformation is fed back as the weighting coefficient, and the channel difference is restored based on the weighting coefficient obtained by accumulating and summing a plurality of discontinuous equivalent channels. Accuracy problems can be avoided, which helps to improve transmission performance. Therefore, while reducing the feedback overhead, higher feedback accuracy can still be ensured.
  • the network device only precodes the reference signal based on the delay vector, and the terminal device performs channel measurement and feedback based on the precoded reference signal. But this should not constitute any limitation to this application.
  • the network device can also pre-encode the reference signal based on the angle vector only, and the terminal device can also perform time-domain transformation on the channel information estimated based on the pre-encoded reference signal based on the similar method described above to obtain the corresponding P P group weighting coefficient of angle delay pair. Since the specific process is similar to that described above, for the sake of brevity, a detailed description is omitted here.
  • FIG. 5 is a schematic flowchart of a channel measurement method 500 provided by an embodiment of the present application from the perspective of device interaction.
  • the method 500 shown in FIG. 5 may include step 510 to step 550.
  • the steps in the method 500 are described in detail below.
  • step 510 the terminal device receives the precoding reference signal.
  • the network device sends the precoding reference signal.
  • step 510 may be the same as the specific process of step 310 in the method 300 above.
  • step 510 reference may be made to the related description of step 310 in the above method 300. For brevity, it will not be repeated here.
  • step 520 the terminal device generates second indication information, which is used to indicate P groups of weighting coefficients corresponding to P transmission ports.
  • the terminal device may perform channel estimation based on the received precoding reference signal, and generate the first indication information based on the estimated channel information.
  • the first indication information may be used to indicate the P sets of weighting coefficients corresponding to the P transmit ports. Wherein, each group of weighting coefficients may include one or more weighting coefficients.
  • the terminal device may feed back P sets of weighting coefficients corresponding to the P transmitting ports based on the receiving port.
  • each group of weighting coefficients may include one or more weighting coefficients.
  • each set of weighting coefficients may include R'weighting coefficients. 1 ⁇ R' ⁇ R, and R'is an integer.
  • the terminal device may also feed back P sets of weighting coefficients corresponding to P transmit ports based on the transmission layer.
  • Each group of weighting coefficients may include Z weighting coefficients, corresponding to Z transmission layers. The specific process of how to determine the weighting coefficients of the P group based on the transmission layer will be described in detail later, which is omitted here.
  • p can be any integer value from 0 to P-1, and the terminal device can execute the following process to determine the corresponding to the p-th transmitting port Weighting factor.
  • Step i Perform channel estimation based on the precoding reference signal of the p-th transmit port received on the r-th receive port, and obtain channel information corresponding to N frequency domain units respectively.
  • the N frequency domain units may be divided into one or more frequency domain unit groups, and each frequency domain unit group includes one or more frequency domain units among the N frequency domain units;
  • Step ii Perform frequency domain filtering on the channel information determined in step i and corresponding to frequency domain units in one or more frequency domain unit groups to obtain filtered N values;
  • Step iii Accumulate and sum the filtered N values determined in step ii, and the obtained value is the weighting coefficient corresponding to the p-th transmitting port and the r-th receiving port.
  • the value of p is traversed in the range of 0 to P-1, and the above process is repeated to obtain the P sets of weighting coefficients corresponding to the P transmitting ports.
  • the following describes in detail the process of determining the P sets of weighting coefficients corresponding to P transmitting ports when the terminal device feeds back the weighting coefficients based on the receiving port.
  • each set of weighting coefficients may include one weighting coefficient.
  • the precoding reference signal of each transmit port may be carried by N RBs (that is, an example of frequency domain unit).
  • a set of weighting coefficients corresponding to each transmission port may include one weighting coefficient.
  • the first indication information may be used to indicate P weighting coefficients corresponding to P transmit ports.
  • the terminal device can perform channel estimation based on the received precoding reference signal of each transmission port to obtain channel information.
  • the channel information may specifically be a channel estimation value obtained by performing channel estimation based on the received precoding reference signal. It can be understood that the channel estimation value may specifically be an equivalent channel, that is, a channel loaded with precoding.
  • P transmit ports can have a one-to-one correspondence with P angle delay pairs.
  • the precoding reference signal corresponding to the p-th transmission port among the P transmission ports may be based on, for example, the k-th angle vector among the K angle vectors and the l-th time delay among the L delay vectors.
  • the vector is obtained by precoding the reference signal. Therefore, the above-mentioned weighting coefficient corresponding to the p-th transmitting port is also the weighting coefficient of the p-th angle delay pair.
  • the terminal device may determine the weight of the p-th angle delay pair based on the channel estimation value obtained by performing channel estimation on the precoding reference signal received on a receiving port and N RBs coefficient.
  • the weighting coefficient of the p-th angle delay pair may be determined by the N channel estimation values on the N RBs.
  • the channel estimation value obtained is recorded as Then the channel estimation value obtained by the terminal equipment based on the precoding reference signal of the p-th transmitting port for channel estimation can be recorded as: A total of N channel estimates. It can be seen that the N channel estimation values correspond to N RBs, that is, to N frequency domain units.
  • step 320 in the method 300 The process of the terminal device performing channel estimation based on the precoding reference signals received on one receiving port and N RBs to obtain N channel estimation values is the same as the process described in step 320 in the method 300 above, and the specific process can refer to the above For the sake of brevity, the related description in step 320 in the method 300 will not be repeated here.
  • the weighting coefficient corresponding to the p-th transmitting port can be obtained by accumulating the channel estimation values on the N RBs.
  • the network device precodes the reference signal based on the delay vector, the N elements in the delay vector are respectively loaded on the N RBs corresponding to the same transmit port. Therefore, the channel estimation value obtained by the terminal equipment estimation on each RB is discontinuous. If the N channel estimation values are directly accumulated and summed as the feedback of the weighting coefficient of the p-th angle delay pair, the recovered downlink channel may also be quite different from the real channel, so it is determined
  • the precoding matrix used for downlink data transmission cannot match the real channel well, thus affecting the system transmission performance.
  • the terminal device may perform filtering processing on the N channel estimation values before accumulating and summing the N channel estimation values.
  • the terminal device may divide the N RBs into one or more RB groups, and each RB group may include multiple RBs, and the RBs in each RB group do not overlap each other.
  • the channel estimation value corresponding to each RB in each RB group is filtered to obtain the filtered value.
  • the accumulated sum of the filtered values (it can be understood that the filtered values are still N), the weighting coefficient corresponding to the p-th transmitting port can be obtained.
  • every 4 RBs are divided into one RB group.
  • RB#0 to RB#3 are used as an RB group
  • RB#4 to RB#7 are used as an RB group
  • RB#8 to RB#11 are used as an RB group
  • RB#12 to RB#15 are used as an RB group.
  • RB#16 to RB#19 serve as one RB group.
  • the terminal device can filter the 5 RB groups respectively to obtain the filtered value. It can be understood that the filtered value is still 20 values. The cumulative sum of the filtered values can be used to obtain the weighting coefficient corresponding to the p-th transmitting port.
  • one or more RBs that are divided into one RB group for filtering may be referred to as a bundled RB (bundling RB, or RB Bundle).
  • this application does not limit the number of RBs included in each RB group. At the same time, this application does not limit the specific rules for dividing the RB group. In other words, this application does not limit the number of frequency domain units included in each frequency domain unit group. At the same time, this application does not limit the specific rules for dividing frequency domain unit groups.
  • the terminal device performs frequency domain filtering on the channel estimation value estimated in each RB group based on the Wiener filter coefficient.
  • the corrected filter coefficient W p can be expressed as:
  • W p represents the filter coefficient corresponding to the p-th transmitting port.
  • Is the correlation matrix which represents the correlation between RBs in an RB group used to carry the reference signal of the p-th transmit port (it can be understood that the reference signal is a precoding reference signal), or if the pilot density is greater than 1. In the case of, it may also represent the correlation between the reference signal REs in an RB group that carries the reference signal of the p-th transmit port.
  • the correlation matrix For the related description of, please refer to the related technology of Wiener filtering in the prior art. For the sake of brevity, detailed description is not given here.
  • the correction value can be used to correct Make corrections.
  • the correction value may be an M ⁇ M-dimensional matrix, and M represents the number of RBs included in each RB group.
  • SNR is the signal-to-noise ratio, referred to as the signal-to-noise ratio.
  • I is the unit matrix.
  • any two frequency domain unit groups contain the same number of frequency domain units.
  • the correction value ⁇ p to be corrected is related to the time delay. among them It is related to the l-th time delay ⁇ l corresponding to the p-th transmit port. For example, it can be the time delay ⁇ p , or the mathematical transformation of the time delay ⁇ p. This application does not limit this. Such as, or, and many more. For the sake of brevity, I will not illustrate them one by one.
  • the mathematical transformation will delay ⁇ p obtained parameters related to the delay ⁇ p is called the parameters of the delay ⁇ p. It should be understood that this application does not limit the specific manner of mathematical transformation.
  • the terminal device since the correction value is related to the time delay, when determining the weighting coefficient corresponding to the p-th transmitting port, the terminal device needs to obtain in advance In other words, time delay ⁇ l or related parameters of time delay ⁇ l.
  • the network device may indicate to the terminal device the delay or delay-related parameters corresponding to each transmission port through signaling in advance.
  • the method 500 further includes: step 530, the network device sends third indication information, where the third indication information is used to indicate the delay or delay related parameters corresponding to each of the P transmission ports .
  • the terminal device receives the third indication information.
  • each delay may correspond to a delay vector used when the network device precodes the reference signal.
  • the indication of the delay by the network device may be, for example, the delay or the index of the corresponding delay vector.
  • the network device an indication of the time delay ⁇ l ⁇ l for example, may be, may be a time delay ⁇ l corresponding to the vector b ( ⁇ l) index.
  • the indication of the related parameters of the delay by the network device may be: the delay ⁇ 0 corresponding to the first transmission port among the P ports, and the first transmission port is divided by the P transmission ports The difference ⁇ between the delays corresponding to the remaining ports and the delay corresponding to the first transmitting port.
  • the first transmission port may be, for example, a certain transmission port predefined by the protocol.
  • the first transmission port may be the 0th transmission port among the P transmission ports, or the P-1 transmission port among the P transmission ports, or the arbitrarily designated transmission port ⁇ 0 .
  • the corresponding time delay is denoted by, for example.
  • the indication of the relevant parameters of the time delay by the terminal device may be, for example, the difference between the time delay corresponding to each transmission port from the first transmission port to the P-1 transmission port and the time delay ⁇ 0 corresponding to the 0th transmission port. value.
  • indicating the delay corresponding to each transmit port by indicating the difference is only a possible implementation.
  • it is also possible to indicate the delay ⁇ 0 corresponding to the first transmit port, and divide the P transmit ports into The ratio of the time delays corresponding to the other transmission ports except the first transmission port to the time delay ⁇ 0 corresponding to the first transmission port is used to indicate the time delays corresponding to each transmission port.
  • This application does not limit the specific manner of indicating the related parameters of the time delay.
  • each frequency domain unit group includes a relevant number of frequency domain units.
  • this application does not limit the number of frequency domain units included in each frequency domain unit group.
  • the number of frequency domain units included in each frequency domain unit group may be the same or different.
  • the aforementioned correction value ⁇ p may be a matrix with a dimension of M max ⁇ M max.
  • M max represents the maximum number of frequency domain units included in each frequency domain unit group. That is, the number of frequency domain units included in each frequency domain unit group is less than or equal to M max .
  • Wiener filtering to filter the channel estimation values on each frequency domain unit is only a possible implementation manner, and this application should not constitute any limitation.
  • the terminal device may also use other possible filtering methods to perform filtering processing on the channel estimation value, for example, filtering constructed based on other criteria (such as non-MMSE), first-order or high-order interpolation, Kalman filtering, etc. For the sake of brevity, I will not list them all here.
  • the terminal device can obtain P sets of weighting coefficients corresponding to the P transmitting ports.
  • Each set of weighting coefficients can include one weighting coefficient.
  • the weighting coefficient corresponding to each transmitting port may include R'weighting coefficients, where R ⁇ R' ⁇ 1.
  • the specific process of the terminal device determining the R'weighting coefficients corresponding to each transmitting port has been described in detail in step 320 of the method 300 above.
  • the specific process for the terminal device to determine the R'weighting coefficients corresponding to each transmission port is similar to the specific process for the terminal device to determine the R'weighting coefficients corresponding to each transmission port in the above method 300. The difference is that in the method 300, the weighting coefficient corresponding to each transmission port is determined based on the time domain transformation, and the weighting coefficient corresponding to each transmission port is determined based on the frequency domain filtering in this embodiment.
  • the processing performed by the terminal device is the same. For the sake of brevity, the different values of R'are not described in detail here.
  • the terminal device may also feed back P sets of weighting coefficients corresponding to P transmit ports based on the transmission layer.
  • the terminal device may determine the P group of weighting coefficients corresponding to the P transmission ports based on the feedback of the transmission layer according to the P group of weighting coefficients corresponding to the P transmission ports determined based on the receiving antenna.
  • the terminal device may determine the P sets of weighting coefficients corresponding to the P transmit ports in each polarization direction based on the same method described above.
  • the specific process for the terminal device to generate the second indication information based on the determined weighting coefficient may refer to the specific process for the terminal device to generate the first indication information in step 330 in the method 300 above. For the sake of brevity, I won't repeat them here.
  • step 540 the terminal device sends the second indication information.
  • step 530 the network device receives the second indication information.
  • step 550 the network device determines a precoding matrix according to the second indication information.
  • step 540 to step 550 may be the same as the specific process from step 330 to step 340 in the method 300 above.
  • step 540 to step 550 reference may be made to the related description of step 330 to step 340 in the method 300 above. For brevity, it will not be repeated here.
  • the network device precodes the downlink reference signal based on, for example, the angle and time delay determined by the uplink channel measurement, so that the terminal device performs downlink channel measurement according to the precoded reference signal. Since the network equipment precodes the reference signal based on the reciprocal angle and time delay of the uplink and downlink channels, the information of the downlink channel detected by the terminal equipment is non-reciprocal information. Therefore, the terminal device does not need to feed back related information in the space domain and the frequency domain (such as the above-mentioned angle vector and delay vector), which greatly reduces the feedback overhead of the terminal device.
  • the channel information estimated on multiple frequency domain units based on the filter coefficients determined by the delay corresponding to each transmit port, noise can be reduced and the pilot frequency on multiple frequency domain units can be fully utilized.
  • the correlation further makes the channel information corresponding to each frequency domain unit obtained by filtering more accurate.
  • the originally discontinuous equivalent channel can be subjected to greater joint filtering, which alleviates the inaccurate channel estimation problem caused by the inability of frequency domain bundling in the current technology, thereby improving the transmission performance. Therefore, while reducing the feedback overhead, it can still ensure high feedback accuracy, which is beneficial to improving the transmission performance of the system.
  • the number of ports of the reference signal can be reduced, thereby reducing the pilot overhead.
  • the above embodiment takes the precoding of the reference signal based on the angle vector and the delay vector as an example to describe the channel measurement method provided in this application in detail. But this should not constitute any limitation to this application.
  • the network device may also pre-encode the reference signal based only on the delay vector or the angle vector, so that the terminal device can perform downlink channel measurement based on the pre-encoded reference signal.
  • the following embodiment takes precoding of the reference signal based only on the delay vector as an example to describe in detail the channel measurement method provided in the present application.
  • FIG. 6 is a schematic flowchart of a channel measurement method 600 according to another embodiment of the present application, shown from the perspective of device interaction.
  • the method 600 shown in FIG. 6 may include step 610 to step 650.
  • the steps in the method 600 are described in detail below.
  • the transmitting antenna of one polarization direction may be any one of the transmitting antennas of J polarization directions configured by the network device. This application does not limit the number J of polarization directions of the transmitting antennas configured by the network equipment.
  • step 610 the terminal device receives the precoding reference signal.
  • the network device sends the precoding reference signal.
  • the network device may precode the reference signal based on the L delay vectors, which may specifically refer to frequency domain precoding.
  • Step 410 in the above method 400 describes in detail the specific process of the network device precoding the reference signal based on the L delay vectors and the relationship between the number of transmission ports and L.
  • step 610 in this embodiment reference may be made to the related description of step 410 in the method 400 above, and for brevity, it will not be repeated here.
  • step 620 the terminal device generates eighth indication information, which is used to indicate P sets of weighting coefficients corresponding to P angle delay pairs.
  • the terminal device may perform channel estimation based on the precoding reference signal of each transmission port received on each RB to obtain channel information corresponding to each transmission port on the N RBs.
  • the terminal device processes each channel estimation value based on the pre-acquired angle vector corresponding to each delay vector to obtain channel information corresponding to each angle delay pair on the N RBs.
  • the terminal device may perform frequency domain filtering on the N channel information corresponding to the same angle delay pair based on the frequency domain filtering method described above.
  • N RBs are divided into one or more RB groups, and each RB group may include one or more RBs.
  • the terminal device may perform frequency domain filtering in units of one RB group corresponding to one angle delay pair.
  • reference may be made to the related description in step 520 in the method 500 above. For the sake of brevity, I won't repeat them here.
  • the terminal device may also obtain L time delays or time delay related parameters in advance before performing step 620.
  • the network device may indicate to the terminal device the delay or delay-related parameters corresponding to each transmission port through signaling in advance.
  • the method 600 further includes: step 630: the network device sends ninth indication information, where the ninth indication information is used to indicate L delays or delay-related parameters.
  • the terminal device receives the ninth indication information.
  • each delay may correspond to a delay vector used when the network device precodes the reference signal.
  • the terminal device may also feed back P sets of weighting coefficients corresponding to P transmit ports based on the transmission layer.
  • the terminal device may determine the P group of weighting coefficients corresponding to the P transmission ports based on the feedback of the transmission layer according to the P group of weighting coefficients corresponding to the P transmission ports determined based on the receiving antenna.
  • the terminal device may determine the P sets of weighting coefficients corresponding to the P transmit ports in each polarization direction based on the same method described above.
  • the specific process for the terminal device to generate the eighth indication information based on the determined weighting coefficient may refer to the specific process for the terminal device to generate the first indication information in step 330 in the method 300 above. For the sake of brevity, I won't repeat them here.
  • step 640 the terminal device sends the eighth indication information.
  • the network device receives the eighth indication information.
  • step 650 the network device determines a precoding matrix according to the eighth indication information.
  • step 640 to step 650 may be the same as the specific process from step 330 to step 340 in the method 300 above.
  • step 640 to step 650 reference may be made to the related description of step 330 to step 340 in the method 300 above. For brevity, it will not be repeated here.
  • the network device precodes the downlink reference signal based on the time delay determined by the uplink channel measurement, so that the terminal device performs the downlink channel measurement according to the precoded reference signal. Since the network device precodes the reference signal based on the reciprocal delay of the uplink and downlink channels, the terminal device does not need to feed back related information in the frequency domain (such as the above-mentioned delay vector), which greatly reduces the feedback overhead of the terminal device. In addition, by filtering the channel information estimated on multiple frequency domain units based on the filter coefficients determined by the delay corresponding to each transmit port, noise can be reduced and the pilot frequency on multiple frequency domain units can be fully utilized. The correlation further makes the channel information corresponding to each frequency domain unit obtained by filtering more accurate.
  • the originally discontinuous equivalent channel can be subjected to greater joint filtering, which alleviates the inaccurate channel estimation problem caused by the inability of frequency domain bundling in the current technology, thereby improving the transmission performance. Therefore, while reducing the feedback overhead, it can still ensure high feedback accuracy, which is beneficial to improving the transmission performance of the system.
  • the network device only precodes the reference signal based on the delay vector, and the terminal device performs channel measurement and feedback based on the precoded reference signal.
  • the network device can also precode the reference signal based on the angle vector only, and the terminal device can also perform frequency domain filtering on the channel information estimated based on the precoded reference signal based on the similar method described above to obtain the corresponding P P group weighting coefficient of angle delay pair. Since the specific process is similar to that described above, for the sake of brevity, a detailed description is omitted here.
  • the terminal device and/or the network device may perform part or all of the steps in the embodiments. These steps or operations are only examples, and the embodiments of the present application may also perform other operations or variations of various operations.
  • each step may be performed in a different order presented in each embodiment, and it may not be necessary to perform all operations in the embodiments of the present application.
  • the size of the sequence number of each step does not mean the order of execution.
  • the execution sequence of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.
  • Fig. 7 is a schematic block diagram of a communication device provided by an embodiment of the present application.
  • the communication device 1000 may include a processing unit 1100 and a transceiving unit 1200.
  • the communication device 1000 may correspond to the terminal device in the above method embodiment, for example, it may be a terminal device, or a component (such as a chip or a chip system, etc.) configured in the terminal device.
  • the communication device 1000 may correspond to the terminal equipment in the method 300 to the method 600 according to the embodiments of the present application, and the communication device 1000 may include a terminal device for executing the method 300 in FIG. 3 to the method 600 in FIG. The unit of the method performed by the device.
  • each unit in the communication device 1000 and the above-mentioned other operations and/or functions are respectively intended to implement the corresponding process of any one of the method 300 in FIG. 3 to the method 600 in FIG. 6.
  • the processing unit 1100 can be used to execute step 320 in the method 300
  • the transceiver unit 1200 can be used to execute step 310 and step 330 in the method 300. It should be understood that the specific process of each unit performing the foregoing corresponding steps has been described in detail in the foregoing method embodiment, and is not repeated here for brevity.
  • the processing unit 1100 can be used to execute step 420 in the method 400, and the transceiver unit 1200 can be used to execute step 410 and step 430 in the method 400. It should be understood that the specific process of each unit performing the foregoing corresponding steps has been described in detail in the foregoing method embodiment, and is not repeated here for brevity.
  • the processing unit 1100 can be used to execute step 520 in the method 500
  • the transceiver unit 1200 can be used to execute step 510, step 530, and step 540 in the method 500. It should be understood that the specific process of each unit performing the foregoing corresponding steps has been described in detail in the foregoing method embodiment, and is not repeated here for brevity.
  • the processing unit 1100 can be used to execute step 620 in the method 600, and the transceiver unit 1200 can be used to execute step 610, step 630, and step 640 in the method 600. It should be understood that the specific process of each unit performing the foregoing corresponding steps has been described in detail in the foregoing method embodiment, and is not repeated here for brevity.
  • the transceiver unit 1200 in the communication device 1000 may be implemented by a transceiver, for example, it may correspond to the transceiver 2020 in the terminal device 2000 shown in FIG.
  • the processing unit 1100 in 1000 may be implemented by at least one processor, for example, may correspond to the processor 2010 in the terminal device 2000 shown in FIG. 8.
  • the transceiver unit 1200 in the communication device 1000 can be implemented through an input/output interface, and the processing unit 1100 in the communication device 1000 can be implemented through the chip or chip.
  • the processor, microprocessor or integrated circuit integrated in the system is implemented.
  • the communication device 1000 may correspond to the network device in the above method embodiment, for example, it may be a network device, or a component (such as a chip or a chip system, etc.) configured in the network device.
  • the communication device 1000 may correspond to the network equipment in the method 300 to the method 600 according to the embodiments of the present application, and the communication device 1000 may include a network device for executing the method 300 in FIG. 3 to the method 600 in FIG. 6 The unit of the method performed by the device.
  • each unit in the communication device 1000 and the above-mentioned other operations and/or functions are respectively intended to implement the corresponding process of any one of the method 300 in FIG. 3 to the method 600 in FIG. 6.
  • the processing unit 1100 can be used to execute step 340 in the method 300
  • the transceiver unit 1200 can be used to execute step 310 and step 330 in the method 300. It should be understood that the specific process of each unit performing the foregoing corresponding steps has been described in detail in the foregoing method embodiment, and is not repeated here for brevity.
  • the processing unit 1100 can be used to execute step 440 in the method 400, and the transceiver unit 1200 can be used to execute step 410 and step 430 in the method 400. It should be understood that the specific process of each unit performing the foregoing corresponding steps has been described in detail in the foregoing method embodiment, and is not repeated here for brevity.
  • the processing unit 1100 may be used to execute step 550 in the method 500
  • the transceiver unit 1200 may be used to execute steps 510, 530, and 540 in the method 500. It should be understood that the specific process of each unit performing the foregoing corresponding steps has been described in detail in the foregoing method embodiment, and is not repeated here for brevity.
  • the processing unit 1100 can be used to execute step 650 in the method 600, and the transceiver unit 1200 can be used to execute step 610, step 630, and step 640 in the method 600. It should be understood that the specific process for each unit to perform the above corresponding steps has been described in detail in the above method embodiment, and will not be repeated here for simplicity.
  • the transceiver unit in the communication device 1000 may be implemented by a transceiver, for example, it may correspond to the transceiver 3200 in the network device 3000 shown in FIG. 9, and the communication device 1000
  • the processing unit 1100 in may be implemented by at least one processor, for example, may correspond to the processor 3100 in the network device 3000 shown in FIG. 9.
  • the transceiver unit 1200 in the communication device 1000 can be implemented through an input/output interface, and the processing unit 1100 in the communication device 1000 can be implemented through the chip or chip.
  • the processor, microprocessor or integrated circuit integrated in the system is implemented.
  • FIG. 8 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 embodiment.
  • the terminal device 2000 includes a processor 2010 and a transceiver 2020.
  • the terminal device 2000 further includes a memory 2030.
  • the processor 2010, the transceiver 2002, and the memory 2030 can communicate with each other through internal connection paths to transfer control and/or data signals.
  • the memory 2030 is used for storing computer programs, and the processor 2010 is used for downloading from the memory 2030. Call and run the computer program to control the transceiver 2020 to send and receive signals.
  • the terminal device 2000 may further include an antenna 2040 for transmitting the uplink data or uplink control signaling output by the transceiver 2020 through a wireless signal.
  • the above-mentioned processor 2010 and the memory 2030 may be combined into a processing device, and the processor 2010 is configured to execute the program code stored in the memory 2030 to realize the above-mentioned functions.
  • 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. 7.
  • the above-mentioned transceiver 2020 may correspond to the transceiver unit in FIG. 7, 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 to receive signals, and the transmitter is used to transmit signals.
  • the terminal device 2000 shown in FIG. 8 can implement various processes involving the terminal device in the method embodiments shown in FIGS. 3 to 6.
  • the operations and/or functions of the various modules in the terminal device 2000 are respectively for implementing the corresponding processes in the foregoing method embodiments.
  • the above-mentioned processor 2010 can be used to execute the actions described in the previous method embodiments implemented by the terminal device, and the transceiver 2020 can be used to execute the terminal device described in the previous method embodiments to send to or receive from the network device. action.
  • the transceiver 2020 can be used to execute the terminal device described in the previous method embodiments to send to or receive from the network device. action.
  • the aforementioned terminal device 2000 may further include a power supply 2050 for providing power to various devices or circuits in the terminal device.
  • the terminal device 2000 may also include one or more of an input unit 2060, a display unit 2070, an audio circuit 2080, a camera 2090, and a sensor 2100.
  • the audio circuit It may also include a speaker 2082, a microphone 2084, and so on.
  • FIG. 9 is a schematic structural diagram of a network device provided by an embodiment of the present application, for example, it may be 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 equipment in the foregoing method embodiment.
  • 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 (BBU) (also known as distributed unit (DU) )) 3200.
  • RRU 3100 may be referred to as a transceiving unit, which corresponds to the transceiving unit 1100 in FIG. 9.
  • the transceiver unit 3100 may also be called a transceiver, a transceiver circuit, or a transceiver, etc., and it may include at least one antenna 3101 and a radio frequency unit 3102.
  • the transceiver unit 3100 may include a receiving unit and a transmitting unit, the receiving unit may correspond to a receiver (or receiver, receiving circuit), and the transmitting unit may correspond to a transmitter (or transmitter or transmitting circuit).
  • the RRU 3100 part is mainly used for sending and receiving of radio frequency signals and conversion of radio frequency signals and baseband signals, for example, for sending instruction information to terminal equipment.
  • the 3200 part of the BBU is mainly used for baseband processing, control of the base station, and so on.
  • the RRU 3100 and the BBU 3200 may be physically set together, or may be physically separated, that is, a distributed base station.
  • the BBU 3200 is the control center of the base station, and may also be called a processing unit, which may correspond to the processing unit 1200 in FIG. 9, and is mainly used to complete baseband processing functions, such as channel coding, multiplexing, modulation, and spreading.
  • the BBU processing unit
  • the BBU may be used to control the base station to execute the operation procedure of the network device in the foregoing method embodiment, for example, to generate the foregoing indication information.
  • the BBU 3200 may be composed of one or more single boards, and multiple single boards may jointly support a radio access network (such as an LTE network) of a single access standard, or support different access standards. Wireless access network (such as LTE network, 5G network or other networks).
  • 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 execute the operation procedure of the network device in the foregoing method embodiment.
  • the memory 3201 and the processor 3202 may serve one or more single boards. In other words, the memory and the processor can be set separately on each board. It can also be that multiple boards share the same memory and processor. In addition, necessary circuits can be provided on each board.
  • the base station 3000 shown in FIG. 9 can implement various processes involving network devices in the method embodiments shown in FIG. 3 to FIG. 6.
  • the operations and/or functions of the various modules in the base station 3000 are respectively for implementing the corresponding procedures in the foregoing method embodiments.
  • the above-mentioned BBU 3200 can be used to perform the actions described in the previous method embodiments implemented by the network device, and the RRU 3100 can be used to perform the actions described in the previous method embodiments that the network device sends to or receives from the terminal device.
  • the RRU 3100 can be used to perform the actions described in the previous method embodiments that the network device sends to or receives from the terminal device.
  • the base station 3000 shown in FIG. 9 is only a possible form of network equipment, and should not constitute any limitation to this application.
  • the method provided in this application can be applied to other types of network equipment.
  • CPE customer premises equipment
  • the CU and/or DU can be used to perform the actions described in the previous method embodiment implemented by the network device, and the AAU can be used to perform the network device described in the previous method embodiment to send to or receive from the terminal device Actions.
  • the AAU can be used to perform the network device described in the previous method embodiment to send to or receive from the terminal device Actions.
  • An embodiment of the present application also provides a processing device, including a processor and an interface; the processor is configured to execute the method in any of the foregoing method embodiments.
  • the aforementioned processing device may be one or more chips.
  • the processing device may be a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on chip (SoC), or It is a central processor unit (CPU), 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.
  • FPGA field programmable gate array
  • ASIC application specific integrated circuit
  • SoC system on chip
  • CPU central processor unit
  • NP network processor
  • DSP digital signal processing circuit
  • microcontroller micro controller unit
  • MCU programmable logic device
  • PLD programmable logic device
  • each step of the above method can be completed by an integrated logic circuit of hardware in the processor or instructions in the form of software.
  • the steps of the method disclosed in the embodiments of the present application may be directly embodied as being executed and completed by a hardware processor, or executed and completed by a combination of hardware and software modules in the processor.
  • the software module can be located in a mature storage medium in the field, such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, registers.
  • 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, it will not be described in detail here.
  • the processor in the embodiment of the present application may be an integrated circuit chip with signal processing capability.
  • the steps of the foregoing method embodiments can be completed by hardware integrated logic circuits in the processor or instructions in the form of software.
  • the above-mentioned processor may be a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components .
  • DSP digital signal processor
  • ASIC application specific integrated circuit
  • FPGA field programmable gate array
  • the methods, steps, and logical block diagrams disclosed in the embodiments of the present application can be implemented or executed.
  • the general-purpose processor may be a microprocessor or the processor may also be any conventional processor or the like.
  • the steps of the method disclosed in the embodiments of the present application can be directly embodied as being executed and completed by a hardware decoding processor, or executed and completed by a combination of hardware and software modules in the decoding processor.
  • the software module can be located in a mature storage medium in the field, such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, registers.
  • 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.
  • the memory in the embodiments 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 can be read-only memory (ROM), programmable read-only memory (programmable ROM, PROM), erasable programmable read-only memory (erasable PROM, EPROM), and electrically available Erase programmable read-only memory (electrically EPROM, EEPROM) or flash memory.
  • the volatile memory may be random access memory (RAM), which is used as an external cache.
  • RAM random access memory
  • static random access memory static random access memory
  • dynamic RAM dynamic RAM
  • DRAM dynamic random access memory
  • synchronous dynamic random access memory 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 connection dynamic random access memory serial DRAM, SLDRAM
  • direct rambus RAM direct rambus RAM
  • the present application also provides a computer program product.
  • the computer program product includes: computer program code, which when the computer program code runs on a computer, causes the computer to execute the steps shown in FIGS. 3 to 6 The method respectively executed by the terminal device and the network device in the illustrated embodiment is shown.
  • the present application also provides a computer-readable medium that stores program code, and when the program code runs on a computer, the computer executes the steps shown in FIGS. 3 to 6 The method respectively executed by the terminal device and the network device in the illustrated embodiment is shown.
  • the present application also 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-mentioned device embodiments corresponds completely to the network equipment or terminal equipment in the terminal equipment and method embodiments, and the corresponding modules or units execute the corresponding steps.
  • the communication unit executes the receiving or the terminal equipment in the method embodiments.
  • the processing unit executes the functions of specific units, refer to the corresponding method embodiments. Among them, there may be one or more processors.
  • component used in this specification are used to denote computer-related entities, hardware, firmware, a combination of hardware and software, software, or software in execution.
  • the component may be, but is not limited to, a process, a processor, an object, an executable file, an execution thread, a program, and/or a computer running on a processor.
  • the application running on the computing device and the computing device can be components.
  • One or more components may reside in processes and/or threads of execution, and components may be located on one computer and/or distributed among two or more computers.
  • these components can be executed from various computer readable media having various data structures stored thereon.
  • the component can be based on, for example, a signal having one or more data packets (e.g. data from two components interacting with another component in a local system, a distributed system, and/or a network, such as the Internet that interacts with other systems through a signal) Communicate through local and/or remote processes.
  • a signal having one or more data packets (e.g. data from two components interacting with another component in a local system, a distributed system, and/or a network, such as the Internet that interacts with other systems through a signal) Communicate through local and/or remote processes.
  • the disclosed system, device, and method may be implemented in other ways.
  • the device embodiments described above are merely illustrative, for example, the division of the units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components may be combined or It can be integrated into another system, or some features can be ignored or not implemented.
  • the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, 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 the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments.
  • the functional units in the various embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit.
  • each functional unit may be implemented in whole or in part by software, hardware, firmware, or any combination thereof.
  • software When implemented by software, it can be implemented in the form of a computer program product in whole or in part.
  • the computer program product includes one or more computer instructions (programs).
  • programs When the computer program instructions (programs) are loaded and executed on the computer, the processes or functions described in the embodiments of the present application are generated in whole or in part.
  • the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices.
  • the computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium.
  • the computer instructions may be transmitted from a website, computer, server, or data center. Transmission to another website, computer, server, or data center via wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as 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 or data center integrated with one or more available media.
  • the usable medium may be a magnetic medium, (for example, a floppy disk, a hard disk, and a magnetic tape), an optical medium (for example, a high-density digital video disc (digital video disc, DVD)), or a semiconductor medium (for example, a solid state disk, SSD)) etc.
  • a magnetic medium for example, a floppy disk, a hard disk, and a magnetic tape
  • an optical medium for example, a high-density digital video disc (digital video disc, DVD)
  • a semiconductor medium for example, a solid state disk, SSD
  • the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer readable storage medium.
  • the technical solution of the present application essentially or the part that contributes to the existing technology or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in the various embodiments of the present application.
  • the aforementioned storage media include: U disk, mobile hard disk, read-only memory (read-only memory, ROM), random access memory (random access memory, RAM), magnetic disks or optical disks and other media that can store program codes. .

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

本申请提供了一种信道测量方法和通信装置。该方法包括：终端设备生成并发送第一指示信息，该第一指示信息用于指示对应于P个发射端口的P组加权系数，P个发射端口中每个发射端口的参考信号基于一时延向量和/或一角度向量对参考信号进行预编码得到，该P个发射端口中每个发射端口对应的加权系数以及每个发射端口对应的时延向量和/或角度向量用于构建预编码矩阵；其中，对应于该P个发射端口中第p个发射端口的第p组加权系数通过对第p个发射端口与终端设备的R个接收端口间的信道信息进行时域变换得到。通过可以利用上、下行信道间的部分互易性，获得下行信道的CSI。并通过时域变换可以获得较为准确的反馈，有利于提供系统传输性能。

Description

一种信道测量方法和通信装置 技术领域
本申请涉及无线通信领域，并且更具体地，涉及一种信道测量方法和通信装置。
背景技术
在大规模多输入多输出(massive multiple-input multiple-output，Massive MIMO)技术中，网络设备可通过预编码减小多用户之间的干扰以及同一用户的多个信号流之间的干扰，有利于提高信号质量，实现空分复用，提高频谱利用率。
终端设备例如可以基于下行信道测量来确定预编码矩阵，并希望通过反馈，使得网络设备获得与终端设备确定的预编码矩阵相同或相近的预编码矩阵。具体地，终端设备例如可以通过反馈一个或多个空域向量、一个或多个频域向量以及一个或多个加权系数的方式来指示构建预编码矩阵。然而，这种反馈方式带来了较大的反馈开销。
在一些通信技术中，如时分双工(time division duplexing，TDD)技术，上行信道和下行信道之间具有互易性，网络设备可以基于对上行信道的测量来估计上行信道。然而还有一些通信技术中，如频分双工(frequency division duplexing，FDD)技术，上、下行信道之间并不是完全互易的。因此，网络设备如何利用上、下行信道间的部分互易性，获得准确的下行信道的信道状态，是亟待解决的技术问题。
发明内容
本申请提供一种信道测量方法和通信装置，以期利用上、下行信道间的部分互易性，获得下行信道的信道状态信息(channel state information，CSI)，提供系统传输性能。
第一方面，提供了一种信道测量方法。该方法可以由终端设备执行，或者，也可以由配置于终端设备中的部件(如芯片或芯片系统等)执行。
具体地，该方法包括：生成第一指示信息，该第一指示信息用于指示对应于P个发射端口的P组加权系数，该P个发射端口中每个发射端口的参考信号基于一时延向量和/或一角度向量对参考信号进行预编码得到，该P个发射端口中每个发射端口对应的加权系数以及每个发射端口对应的时延向量和/或角度向量用于构建预编码矩阵；其中，对应于该P个发射端口中第p个发射端口的第p组加权系数通过对该第p个发射端口与终端设备的R个接收端口间的信道信息进行时域变换得到，该第p个发射端口是该P个发射端口中的任意一个发射端口，0≤p≤P-1，P≥1，R≥1，p、P和R均为整数；发送该第一指示信息。
应理解，上述参考信号可以是基于角度向量和时延向量中的一项进行预编码得到，也可以是基于角度向量和时延向量进行预编码得到。本申请对此不作限定。终端设备可以基于接收到的参考信号进行信道测量，以反馈与各发射端口对应的加权系数。可以理解，与各发射端口对应的加权系数也可以是指与角度向量和时延向量对应的加权系数。
基于上述技术方案，网络设备例如可以基于上行信道测量所确定的角度和时延，对下 行参考信号进行预编码，使得终端设备根据预编码后的参考信号进行下行信道测量。由于网络设备基于上下行信道可互易的角度和/或时延对参考信号进行了预编码，终端设备可以不必反馈空域和/或频域的向量(如上述角度向量和/或时延向量)，大大减小了终端设备的反馈开销。
此外，终端设备基于接收到的预编码参考信号进行信道测量时，将所测量到的频域的信道转换到时域，将时域变换所得到的值作为角度时延对的加权系数来反馈。从而可以避免由多个不连续的等效信道进行累加求和得到的加权系数而恢复的信道不准确的问题，有利于获得较高的反馈精度，因此有利于网络设备基于反馈确定与下行信道适配的预编码矩阵，有利于提高系统的传输性能。
结合第一方面，在第一方面的某些可能的实现方式中，所述P组加权系数中的每组加权系数包括R’个加权系数，所述第p组加权系数是通过对所述第p个发射端口与所述R个接收端口中的一个或多个接收端口间的信道信息进行时域变换得到；R≥R’≥1，R’为整数。
也就是说，每组加权系数可以与一个发射端口对应，每组加权系数中的加权系数例如可以由一个发射端口和一个接收端口间的信道信息进行时域变换得到，也可以由一个发射端口和多个接收端口间的信道信息的加权进行时域变换得到。本申请对此不作限定。
进一步地，所述P组加权系数中的每组加权系数包括对应于所述R个接收端口的R个加权系数，所述第p组加权系数中的第r个加权系数通过对所述第p个发射端口与所述R个接收端口中的第r个接收端口间的信道信息进行时域变换得到。
也就是说，每组加权系数中的每个加权系数可以是由一个发射端口和一个接收端口间的信道信息进行时域变换得到。
结合第一方面，在第一方面的某些可能的实现方式中，该方法还包括：对所述第p个发射端口与所述第r个接收端口间的信道信息所确定的向量进行时域变换，得到变换后的向量，所述第p组加权系数中的第r个加权系数是经所述时域变换得到的向量中的第n p,r个值；其中，所述第p个发射端口与所述第r个接收端口间的信道信息所确定的向量包括N个值，所述N个值包括用于承载所述第p个发射端口的参考信号的N个频域单元分别对应的信道信息，0≤n p,r≤N-1，N≥1，n p,r和N均为整数。
可选地，时域变换包括：快速傅里叶逆变换(inverse fast Fourier transform，IFFT)或离散傅里叶逆变换(inverse discrete Fourier Transform，IDFT)。
上文提供了一种通过时域变换获得加权系数的方式。但应理解，上文列举仅为示例，不应该对本申请构成任何限定。本申请对于时域变换的具体实现方式不作限定。
可选地，n p,r为预定义值。作为一个示例，n p,r＝0。
由于对该N个信道估计值进行IFFT变换之后所得到的N个时域变换值中，首个时域变换值(也就是直流分量)正好等于该N个信道估计值的累加和，该N个信道估计值是基于N个频域单元上接收到的同一个发射端口的参考信号估计得到。因此，可以将n p,r定义为0。
应理解，这里仅为便于理解，以IFFT为例详细说明了将n p,r定义为0的原因。但这不应对本申请构成任何限定。由于时域变换的方式并不限于上文所列举，在不同的实现方式中，对n p,r的定义也可以不同。本申请对此不作限定。
可选地，所述第一指示信息还用于指示与所述第p个发射端口和所述第r个接收端口 间的信道对应的n p,r的值。
也就是说，终端设备可以自行决定将N个时域变换值中的哪一个确定为加权系数，即，终端设备可以自行确定n p,r的值并上报网络设备。
结合第一方面，在第一方面的某些可能的实现方式中，该方法还包括：基于预先确定的滤波系数，对变换后的向量进行滤波处理，得到第p组加权系数中的第r个加权系数；其中，该滤波系数包括N个元素，该N个元素中包括一个非零元素和N-1个零元素，该非零元素为该N个元素中的第n p,r个元素。
如前所述，终端设备可以从时域变换得到的向量中选择一个值作为加权系数。终端设备将N个时域变换值中的某一个值作为加权系数的具体过程可以通过滤波来实现。上文提供了一种滤波方法，通过预先确定的滤波系数对上述时域变换所得到的向量进行滤波处理，便于终端设备从该向量中获得可作为加权系数的值。
示例性地，基于上文所列举的n p,r＝0，该滤波系数例如可以表示为[1 0 … 0] 1×N。
应理解，上文列举的方法和滤波系数仅为示例，不应对本申请构成任何限定。本申请对于滤波的具体方式和滤波系数的具体形式不作限定。
第二方面，提供了一种信道测量方法。该方法可以由终端设备执行，或者，也可以由配置于终端设备中的部件(如芯片或芯片系统等)执行。
具体地，该方法包括：生成第二指示信息，该第二指示信息用于指示对应于P个发射端口的P组加权系数，该P个发射端口中每个发射端口的参考信号至少基于一时延向量对参考信号进行预编码得到，该P个发射端口中每个发射端口对应的加权系数以及每个发射端口对应的时延向量用于构建预编码矩阵；其中，对应于该P个发射端口中的第p个发射端口的第p组加权系数是对一个或多个频域单元组的信道信息分别进行滤波所得的多个值之和，该一个或多个频域单元组中的每个频域单元组包括多个频域单元，且该一个或多个频域单元组所包括的频域单元的总数目是是用于承载该第p个发射端口的参考信号的频域单元的数目，该第p个发射端口是该P个发射端口中的任意一个发射端口，0≤p≤P-1，P≥1，p、P均为整数；发送该第二指示信息。
应理解，上述与每个发射端口对应的参考信号可以是基于时延向量预编码得到，也可以是基于角度向量和时延向量进行预编码得到。本申请对此不作限定。终端设备可以基于接收到的参考信号进行信道测量，以反馈与各发射端口对应的加权系数。可以理解，与各发射端口对应的加权系数也可以是指与角度向量和时延向量对应的加权系数。
基于上述技术方案，网络设备例如可以基于上行信道测量所确定的时延，对下行参考信号进行预编码，使得终端设备根据预编码后的参考信号进行下行信道测量。由于网络设备基于上下行信道可互易的时延对参考信号进行了预编码，终端设备可以不必反馈频域的相关信息(如上述时延向量)，大大减小了终端设备的反馈开销。
此外，通过对多个频域单元上估计所得到的信道信息进行滤波处理，可以降低噪声，使得滤波所得的与各个频域单元对应的信道信息更为准确。从而可以提高信道测量和反馈的精度，有利于网络设备基于反馈确定与下行信道适配的预编码矩阵，有利于提高系统的传输性能。
结合第二方面，在第二方面的某些可能的实现方式中，该方法还包括：基于预先确定的与该第p个发射端口对应的滤波系数，分别对该一个或多个频域单元组的信道信息进行滤波，以得到滤波后的值；将该一个或多个频域单元组的滤波后的值求和，得到对应于该 第p个发射端口的加权系数。
也就是说，终端设备可以基于每个发射端口对应的滤波系数，对基于该发射端口对应的信道信息进行滤波。与该发射端口对应的信道信息可以是由终端设备基于对该发射端口对一个的参考信号的接收进行信道估计得到。
结合第二方面，在第二方面的某些可能的实现方式中，该方法还包括：基于与该第p个发射端口对应的时延τ p或时延τ p的相关参数，确定该滤波系数，其中每个时延对应于一个时延向量。
可以看到，该滤波系数与发射端口所对应的时延相关。也就是说，终端设备对某一发射端口所对应的信道信息进行滤波所使用的滤波系数与该发射端口所对应的时延相关。
可选地，滤波系数为：
Figure PCTCN2019114491-appb-000001
其中，
Figure PCTCN2019114491-appb-000002
其中，
Figure PCTCN2019114491-appb-000003
为相关矩阵，表示用于承载该第p个发射端口的参考信号的一个频域单元组中各频域单元之间的相关性；
Figure PCTCN2019114491-appb-000004
为修正值，用于对
Figure PCTCN2019114491-appb-000005
进行修正，
Figure PCTCN2019114491-appb-000006
为与该第p个发射端口对应的时延τ p或与时延τ p的相关参数，N表示用于承载该第p个发射端口的参考信号的频域单元的数目，N＞1且为整数；
Figure PCTCN2019114491-appb-000007
为对
Figure PCTCN2019114491-appb-000008
进行修正得到的相关矩阵；SNR为信号噪声比；I表示单位阵。
上文给出了维纳滤波系数的一例。在本申请实施例中，该维纳滤波系数中引入了与时延相关的修正值，可实现对现有技术中的维纳滤波系数的补偿。可以看到，该修正值与发射端口所对应的时延相关，充分利用了同一个端口的多个频域单元上导频间的相关性，使得滤波所得的与各个频域单元对应的信道信息更为准确，并使得原本不连续的等效信道可以进行更大程度的联合滤波。从而可以缓解当前技术中无法将频域资源绑定而造成的信道估计不准确问题。
应理解，上文列举的维纳滤波系数仅为示例，不应对本申请构成任何限定。本申请对于滤波系数的具体形式不作限定。
结合第二方面，在第二方面的某些可能的实现方式中，该方法还包括：接收第三指示信息，该第三指示信息用于指示与该P个发射端口中每个发射端口对应的时延或时延的相关参数，每个时延对应于一个时延向量。
通过向终端设备指示与每个发射端口对应的时延或时延的相关的系数，便于终端设备 确定上述滤波系数，从而实现对估计所得的信道信息的滤波。
可选地，该第三指示信息对该P个发射端口中每个发射端口对应的时延指示为与每个发射端口对应的时延。
可选地，该第三指示信息对该P个发射端口中每个发射端口对应的时延的相关参数的指示为：该P个端口中的第一发射端口对应的时延τ 0，以及该P个发射端口中除该第一发射端口之外的其余端口对应的时延与该第一发射端口对应的时延的差值Δτ。
上文提供了两种用于指示时延的可能的实现方式。应理解，上文列举仅为示例，不应对本申请构成任何限定。本申请对于指示与发射端口对应的时延的具体实现方式不作限定。
第三方面，提供了一种通信装置，包括用于执行第一方面中任一种可能实现方式中的方法的各个模块或单元。
第四方面，提供了一种通信装置，包括处理器。该处理器与存储器耦合，可用于执行存储器中的指令，以实现上述第一方面中任一种可能实现方式中的方法。可选地，该通信装置还包括存储器。可选地，该通信装置还包括通信接口，处理器与通信接口耦合。
在一种实现方式中，该通信装置为终端设备。当该通信装置为终端设备时，所述通信接口可以是收发器，或，输入/输出接口。
在另一种实现方式中，该通信装置为配置于终端设备中的芯片。当该通信装置为配置于终端设备中的芯片时，所述通信接口可以是输入/输出接口。
可选地，所述收发器可以为收发电路。可选地，所述输入/输出接口可以为输入/输出电路。
第五方面，提供了一种通信装置，包括用于执行第二方面中任一种可能实现方式中的方法的各个模块或单元。
第六方面，提供了一种通信装置，包括处理器。该处理器与存储器耦合，可用于执行存储器中的指令，以实现上述第二方面中任一种可能实现方式中的方法。可选地，该通信装置还包括存储器。可选地，该通信装置还包括通信接口，处理器与通信接口耦合。
在一种实现方式中，该通信装置为接入网设备。当该通信装置为接入网设备时，所述通信接口可以是收发器，或，输入/输出接口。
在另一种实现方式中，该通信装置为配置于接入网设备中的芯片。当该通信装置为配置于接入网设备中的芯片时，所述通信接口可以是输入/输出接口。
可选地，所述收发器可以为收发电路。可选地，所述输入/输出接口可以为输入/输出电路。
第七方面，提供了一种处理器，包括：输入电路、输出电路和处理电路。所述处理电路用于通过所述输入电路接收信号，并通过所述输出电路发射信号，使得所述处理器执行上述第一方面和第二方面中任一种可能实现方式中的方法。
在具体实现过程中，上述处理器可以为芯片，输入电路可以为输入管脚，输出电路可以为输出管脚，处理电路可以为晶体管、门电路、触发器和各种逻辑电路等。输入电路所接收的输入的信号可以是由例如但不限于接收器接收并输入的，输出电路所输出的信号可以是例如但不限于输出给发射器并由发射器发射的，且输入电路和输出电路可以是同一电路，该电路在不同的时刻分别用作输入电路和输出电路。本申请实施例对处理器及各种电路的具体实现方式不做限定。
第八方面，提供了一种处理装置，包括处理器和存储器。该处理器用于读取存储器中存储的指令，并可通过接收器接收信号，通过发射器发射信号，以执行第一方面和第二方面中任一种可能实现方式中的方法。
可选地，所述处理器为一个或多个，所述存储器为一个或多个。
可选地，所述存储器可以与所述处理器集成在一起，或者所述存储器与处理器分离设置。
在具体实现过程中，存储器可以为非瞬时性(non-transitory)存储器，例如只读存储器(read only memory，ROM)，其可以与处理器集成在同一块芯片上，也可以分别设置在不同的芯片上，本申请实施例对存储器的类型以及存储器与处理器的设置方式不做限定。
应理解，相关的数据交互过程例如发送指示信息可以为从处理器输出指示信息的过程，接收能力信息可以为处理器接收输入能力信息的过程。具体地，处理输出的数据可以输出给发射器，处理器接收的输入数据可以来自接收器。其中，发射器和接收器可以统称为收发器。
上述第八方面中的装置可以是芯片，该处理器可以通过硬件来实现也可以通过软件来实现，当通过硬件实现时，该处理器可以是逻辑电路、集成电路等；当通过软件来实现时，该处理器可以是一个通用处理器，通过读取存储器中存储的软件代码来实现，该存储器可以集成在处理器中，可以位于该处理器之外，独立存在。
第九方面，提供了一种计算机程序产品，所述计算机程序产品包括：计算机程序(也可以称为代码，或指令)，当所述计算机程序被运行时，使得计算机执行上述第一方面和第二方面中任一种可能实现方式中的方法。
第十方面，提供了一种计算机可读介质，所述计算机可读介质存储有计算机程序(也可以称为代码，或指令)当其在计算机上运行时，使得计算机执行上述第一方面和第二方面中任一种可能实现方式中的方法。
第十一方面，提供了一种通信系统，包括前述的终端设备和网络设备。
附图说明
图1是适用于本申请实施例提供的信道测量方法的通信系统的架构示意图；
图2是本申请实施例提供的基于时延向量对参考信号进行预编码的示意图；
图3是本申请一实施例提供的信道测量方法的示意性流程图；
图4是本申请另一实施例提供的信道测量方法的示意性流程图；
图5是本申请又一实施例提供的信道测量方法的示意性流程图；
图6是本申请再一实施例提供的信道测量方法的示意性流程图；
图7是本申请实施例提供的通信装置的示意性框图；
图8是本申请实施例提供的终端设备的结构示意图；
图9是本申请实施例提供的网络设备的结构示意图。
具体实施方式
下面将结合附图，对本申请中的技术方案进行描述。
本申请实施例的技术方案可以应用于各种通信系统，例如：长期演进(Long Term  Evolution，LTE)系统、LTE频分双工(frequency division duplex，FDD)系统、LTE时分双工(time division duplex，TDD)、通用移动通信系统(universal mobile telecommunication system，UMTS)、全球互联微波接入(worldwide interoperability for microwave access，WiMAX)通信系统、未来的第五代(5th Generation，5G)移动通信系统或新无线接入技术(new radio Access Technology，NR)。其中，5G移动通信系统可以包括非独立组网(non-standalone，NSA)和/或独立组网(standalone，SA)。
本申请提供的技术方案还可以应用于机器类通信(machine type communication，MTC)、机器间通信长期演进技术(Long Term Evolution-machine，LTE-M)、设备到设备(device-to device，D2D)网络、机器到机器(machine to machine，M2M)网络、物联网(internet of things，IoT)网络或者其他网络。其中，IoT网络例如可以包括车联网。其中，车联网系统中的通信方式统称为车到其他设备(vehicle to X，V2X，X可以代表任何事物)，例如，该V2X可以包括：车辆到车辆(vehicle to vehicle，V2V)通信，车辆与基础设施(vehicle to infrastructure，V2I)通信、车辆与行人之间的通信(vehicle to pedestrian，V2P)或车辆与网络(vehicle to network，V2N)通信等。
本申请提供的技术方案还可以应用于未来的通信系统，如第六代移动通信系统等。本申请对此不作限定。
本申请实施例中，网络设备可以是任意一种具有无线收发功能的设备。该设备包括但不限于：演进型节点B(evolved Node B，eNB)、无线网络控制器(radio network controller，RNC)、节点B(Node B，NB)、基站控制器(base station controller，BSC)、基站收发台(base transceiver station，BTS)、家庭基站(例如，home evolved NodeB，或home Node B，HNB)、基带单元(baseband unit，BBU)，无线保真(wireless fidelity，WiFi)系统中的接入点(access point，AP)、无线中继节点、无线回传节点、传输点(transmission point，TP)或者发送接收点(transmission and reception point，TRP)等，还可以为5G，如，NR，系统中的gNB，或，传输点(TRP或TP)，5G系统中的基站的一个或一组(包括多个天线面板)天线面板，或者，还可以为构成gNB或传输点的网络节点，如基带单元(BBU)，或，分布式单元(distributed unit，DU)等。
在一些部署中，gNB可以包括集中式单元(centralized unit，CU)和DU。gNB还可以包括有源天线单元(active antenna unit，AAU)。CU实现gNB的部分功能，DU实现gNB的部分功能，比如，CU负责处理非实时协议和服务，实现无线资源控制(radio resource control，RRC)，分组数据汇聚层协议(packet data convergence protocol，PDCP)层的功能。DU负责处理物理层协议和实时服务，实现无线链路控制(radio link control，RLC)层、介质接入控制(medium access control，MAC)层和物理(physical，PHY)层的功能。AAU实现部分物理层处理功能、射频处理及有源天线的相关功能。由于RRC层的信息最终会变成PHY层的信息，或者，由PHY层的信息转变而来，因而，在这种架构下，高层信令，如RRC层信令，也可以认为是由DU发送的，或者，由DU+AAU发送的。可以理解的是，网络设备可以为包括CU节点、DU节点、AAU节点中一项或多项的设备。此外，可以将CU划分为接入网(radio access network，RAN)中的网络设备，也可以将CU划分为核心网(core network，CN)中的网络设备，本申请对此不做限定。
网络设备为小区提供服务，终端设备通过网络设备分配的传输资源(例如，频域资源，或者说，频谱资源)与小区进行通信，该小区可以属于宏基站(例如，宏eNB或宏gNB 等)，也可以属于小小区(small cell)对应的基站，这里的小小区可以包括：城市小区(metro cell)、微小区(micro cell)、微微小区(pico cell)、毫微微小区(femto cell)等，这些小小区具有覆盖范围小、发射功率低的特点，适用于提供高速率的数据传输服务。
在本申请实施例中，终端设备也可以称为用户设备(user equipment，UE)、接入终端、用户单元、用户站、移动站、移动台、远方站、远程终端、移动设备、用户终端、终端、无线通信设备、用户代理或用户装置。
终端设备可以是一种向用户提供语音/数据连通性的设备，例如，具有无线连接功能的手持式设备、车载设备等。目前，一些终端的举例可以为：手机(mobile phone)、平板电脑(pad)、带无线收发功能的电脑(如笔记本电脑、掌上电脑等)、移动互联网设备(mobile internet device，MID)、虚拟现实(virtual reality，VR)设备、增强现实(augmented reality，AR)设备、工业控制(industrial control)中的无线终端、无人驾驶(self driving)中的无线终端、远程医疗(remote medical)中的无线终端、智能电网(smart grid)中的无线终端、运输安全(transportation safety)中的无线终端、智慧城市(smart city)中的无线终端、智慧家庭(smart home)中的无线终端、蜂窝电话、无绳电话、会话启动协议(session initiation protocol，SIP)电话、无线本地环路(wireless local loop，WLL)站、个人数字助理(personal digital assistant，PDA)、具有无线通信功能的手持设备、计算设备或连接到无线调制解调器的其它处理设备、车载设备、可穿戴设备，5G网络中的终端设备或者未来演进的公用陆地移动通信网络(public land mobile network，PLMN)中的终端设备等。
其中，可穿戴设备也可以称为穿戴式智能设备，是应用穿戴式技术对日常穿戴进行智能化设计、开发出可以穿戴的设备的总称，如眼镜、手套、手表、服饰及鞋等。可穿戴设备即直接穿在身上，或是整合到用户的衣服或配件的一种便携式设备。可穿戴设备不仅仅是一种硬件设备，更是通过软件支持以及数据交互、云端交互来实现强大的功能。广义穿戴式智能设备包括功能全、尺寸大、可不依赖智能手机实现完整或者部分的功能，例如：智能手表或智能眼镜等，以及只专注于某一类应用功能，需要和其它设备如智能手机配合使用，如各类进行体征监测的智能手环、智能首饰等。
此外，终端设备还可以是物联网(internet of things，IoT)系统中的终端设备。IoT是未来信息技术发展的重要组成部分，其主要技术特点是将物品通过通信技术与网络连接，从而实现人机互连，物物互连的智能化网络。IoT技术可以通过例如窄带(narrow band)NB技术，做到海量连接，深度覆盖，终端省电。
此外，终端设备还可以包括智能打印机、火车探测器、加油站等传感器，主要功能包括收集数据(部分终端设备)、接收网络设备的控制信息与下行数据，并发送电磁波，向网络设备传输上行数据。
为便于理解本申请实施例，首先结合图1详细说明适用于本申请实施例提供的方法的通信系统。图1示出了适用于本申请实施例提供的方法的通信系统100的示意图。如图所示，该通信系统100可以包括至少一个网络设备，如图1中所示的5G系统中的网络设备101；该通信系统100还可以包括至少一个终端设备，如图1中所示的终端设备102至107。其中，该终端设备102至107可以是移动的或固定的。网络设备101和终端设备102至107中的一个或多个均可以通过无线链路通信。每个网络设备可以为特定的地理区域提供通信覆盖，并且可以与位于该覆盖区域内的终端设备通信。例如，网络设备可以向终端设备发送配置信息，终端设备可以基于该配置信息向网络设备发送上行数据；又例如，网络 设备可以向终端设备发送下行数据。因此，图1中的网络设备101和终端设备102至107构成一个通信系统。
可选地，终端设备之间可以直接通信。例如可以利用D2D技术等实现终端设备之间的直接通信。如图中所示，终端设备105与106之间、终端设备105与107之间，可以利用D2D技术直接通信。终端设备106和终端设备107可以单独或同时与终端设备105通信。
终端设备105至107也可以分别与网络设备101通信。例如可以直接与网络设备101通信，如图中的终端设备105和106可以直接与网络设备101通信；也可以间接地与网络设备101通信，如图中的终端设备107经由终端设备106与网络设备101通信。
应理解，图1示例性地示出了一个网络设备和多个终端设备，以及各通信设备之间的通信链路。可选地，该通信系统100可以包括多个网络设备，并且每个网络设备的覆盖范围内可以包括其它数量的终端设备，例如更多或更少的终端设备。本申请对此不做限定。
上述各个通信设备，如图1中的网络设备101和终端设备102至107，可以配置多个天线。该多个天线可以包括至少一个用于发送信号的发射天线和至少一个用于接收信号的接收天线。另外，各通信设备还附加地包括发射机链和接收机链，本领域普通技术人员可以理解，它们均可包括与信号发送和接收相关的多个部件(例如处理器、调制器、复用器、解调器、解复用器或天线等)。因此，网络设备与终端设备之间可通过多天线技术通信。
可选地，该无线通信系统100还可以包括网络控制器、移动管理实体等其他网络实体，本申请实施例不限于此。
为了便于理解本申请实施例，下面简单说明下行信号在发送之前在物理层的处理过程。应理解，下文所描述的对下行信号的处理过程可以由网络设备执行，也可以由配置于网络设备中的芯片执行。为方便说明，下文统称为网络设备。
网络设备在物理信道可对码字(code word)进行处理。其中，码字可以为经过编码(例如包括信道编码)的编码比特。码字经过加扰(scrambling)，生成加扰比特。加扰比特经过调制映射(modulation mapping)，得到调制符号。调制符号经过层映射(layer mapping)，被映射到多个层(layer)，或者称，传输层。经过层映射后的调制符号经过预编码(precoding)，得到预编码后的信号。预编码后的信号经过资源元素(resource element，RE)映射后，被映射到多个RE上。这些RE随后经过正交复用(orthogonal frequency division multiplexing，OFDM)调制后通过天线端口(antenna port)发射出去。
应理解，上文所描述的对下行信号的处理过程仅为示例性描述，不应对本申请构成任何限定。对下行信号的处理过程具体可以参考现有技术，为了简洁，这里省略对其具体过程的详细说明。
为便于理解本申请实施例，下面对本申请实施例中涉及到的术语做简单介绍。
1、预编码技术：网络设备可以在已知信道状态的情况下，借助与信道状态相匹配的预编码矩阵来对待发送信号进行处理，使得经过预编码的待发送信号与信道相适配，从而使得接收设备消除信道间影响的复杂度降低。因此，通过对待发送信号的预编码处理，接收信号质量(例如信号与干扰加噪声比(signal to interference plus noise ratio，SINR)等)得以提升。因此，采用预编码技术，可以实现发送设备与多个接收设备在相同的时频资源上传输，也就是实现了多用户多输入多输出(multiple user multiple input multiple output，MU-MIMO)。应理解，本文中有关预编码技术的相关描述仅为便于理解而示例，并非用 于限制本申请实施例的保护范围。在具体实现过程中，发送设备还可以通过其他方式进行预编码。例如，在无法获知信道信息(例如但不限于信道矩阵)的情况下，采用预先设置的预编码矩阵或者加权处理方式进行预编码等。为了简洁，其具体内容本文不再赘述。
2、信道互易性：在某些通信模式中，如TDD中，上下行信道在相同的频域资源上不同的时域资源上传输信号。在相对较短的时间(如，信道传播的相干时间)之内，可以认为上、下行信道上的信号所经历的信道衰落是相同的。这就是上下行信道的互易性。基于上下行信道的互易性，网络设备可以根据上行参考信号，如探测参考信号(sounding reference signal，SRS)，测量上行信道。并可以根据上行信道来估计下行信道，从而可以确定用于下行传输的预编码矩阵。
然而，在另一些通信模式中，如FDD中，由于上下行信道的频带间隔远大于相干带宽，上下行信道不具有完整的互易性，利用上行信道来确定用于下行传输的预编码矩阵可能并不能够与下行信道相适配。但是，FDD模式下的上下行信道仍然具有部分的互易性，例如，角度的互易性和时延的互易性。因此，角度和时延也可以称为互易性参数。
信号在经过无线信道传输时，从发射天线可以经过多个路径到达接收天线。多径时延导致频率选择性衰落，就是频域信道的变化。时延是无线信号在不同传输路径上的传输时间，由距离和速度决定，与无线信号的频域没有关系。信号在不同的传输路径上传输时，由于距离不同，存在不同的传输时延。由于网络设备与终端设备之间的物理位置是固定的，因而上下行信道的多径分布在时延上是相同的。因此，时延在FDD模式下的上下行信道可以认为是相同的，或者说，互易的。
此外，角度可以是指信号经由无线信道到达接收天线的到达角(angle of arrival，AOA)，也可以是指通过发射天线发射信号的离开角(angle of departure，AOD)。在本申请实施例中，该角度可以是指上行信号到达网络设备的到达角，也可以是指网络设备发射下行信号的离开角。由于上下行信道在不同频率上的传输路径的互易，该上行参考信号的到达角和下行参考信号的离开角可以认为是互易的。
在本申请实施例中，每个角度可以通过一个角度向量来表征。每个时延可通过一个时延向量来表征。因此，在本申请实施例中，一个角度向量可以表示一个角度，一个时延向量可以表示一个时延。
3、参考信号(reference signal，RS)与预编码参考信号：参考信号也可以称为导频(pilot)、参考序列等。在本申请实施例中，参考信号可以是用于信道测量的参考信号。例如，该参考信号可以是用于下行信道测量的信道状态信息参考信号(channel state information reference signal，CSI-RS)，也可以是用于上行信道测量的SRS。应理解，上文列举的参考信号仅为示例，不应对本申请构成任何限定。本申请并不排除在未来的协议中定义其他参考信号以实现相同或相似功能的可能。
预编码参考信号可以是对参考信号进行预编码后得到的参考信号。其中，预编码具体可以包括波束赋形(beamforming)和/或相位旋转。其中，波束赋形例如可以通过基于一个或多个角度向量对下行参考信号进行预编码来实现，相位旋转例如可以通过将一个或多个时延向量对下行参考信号进行预编码来实现。
在本申请实施例中，为方便区分和说明，将经过预编码，如波束赋形和/或相位旋转，得到的参考信号称为预编码参考信号；未经过预编码的参考信号简称为参考信号。
在本申请实施例中，基于一个或多个角度向量对下行参考信号进行预编码，也可以称 为，将一个或多个角度向量加载到下行参考信号上，以实现波束赋形。基于一个或多个时延向量对下行参考信号进行预编码，也可以称为将一个或多个时延向量加载到下行参考信号上，以实现相位旋转。
4、端口(port)：可以包括发射端口和接收端口。
其中，发射端口可以理解为被接收设备所识别的虚拟天线。
可选地，端口可以是指发射天线端口。例如，每个发射天线端口的参考信号可以是未经过预编码的参考信号。其中，发射天线端口，可以是指实际的独立发送单元(transceiver unit，TxRU)。
可选地，端口也可以是指经过波束赋形后的端口。例如，每个端口的参考信号可以是基于一个角度向量对参考信号进行预编码得到的预编码参考信号。可以理解的是，若对参考信号做了波束赋形，则端口数可以是指预编码参考信号的端口数。该预编码参考信号的端口数可以小于发射天线端口数。
可选地，端口也可以是指经过相位旋转后的端口，例如，每个端口的参考信号可以是基于一个时延向量对参考信号进行预编码且通过一个发射天线端口发送的预编码参考信号。该端口也可以称为预编码参考信号的端口。
可选地，端口也可以是指经过波束赋形和相位旋转后的端口。例如，每个端口的参考信号可以是基于一个角度向量和一个时延向量对参考信号进行预编码得到的预编码参考信号。该端口也可以称为预编码参考信号的端口。
每个端口的参考信号可以通过一个或者多个频域单元传输。
在下文示出的实施例中，在涉及发射天线端口时，可以是指未进行空域预编码的端口数。即，是实际的独立发送单元数。在涉及端口时，在不同的实施例中，可以是指发射天线端口，也可以是指预编码参考信号的端口。端口所表达的具体含义可以根据具体实施例来确定。下文中为方便区分，将预编码参考信号的端口称为参考信号端口。
接收端口可以理解为接收设备的接收天线。例如在下行传输中，接收端口可以是指终端设备的接收天线。
5、角度向量：可以理解为用于对参考信号进行波束赋形的预编码向量。通过波束赋形，可以使得发送设备发射出来的参考信号具有一定的空间指向性。因此，基于角度向量对参考信号进行预编码的过程也可以视为是空间域(或简称，空域)预编码的过程。因此角度向量也可以称为空域向量、波束(beam)向量等。
基于一个或多个角度向量对参考信号进行预编码后得到的预编码参考信号的端口数与角度向量的个数相同。当角度向量的个数K小于一个极化方向上的发射天线端口数T时，可以通过空域预编码来实现天线端口的降维，从而减小导频开销。其中K≥1，T≥1，且K、T均为整数。
角度向量可以是一长度为T的向量。
可选地，角度向量是离散傅里叶变换(Discrete Fourier Transform，DFT)向量。DFT向量可以是指DFT矩阵中的向量。
可选地，角度向量是DFT向量的共轭转置向量。DFT共轭转置向量可以是指DFT矩阵的共轭转置矩阵中的列向量。
可选地，角度向量是过采样DFT向量。过采样DFT向量可以是指过采样DFT矩阵中的向量。
在一种可能的设计中，该角度向量例如可以是NR协议TS 38.214版本15(release 15，R15)中类型II(type II)码本中定义的二维(2 dimensions，2D)-DFT向量v l,m。换句话说，角度向量可以是2D-DFT向量或过采样2D-DFT向量。
如
Figure PCTCN2019114491-appb-000009
其中，I 1为天线阵列中每一列(或行)中包含的同一极化方向的天线端口数，I 2为天线阵列中每一行(或列)包含的同一极化方向的天线端口数。在本实施例中，T＝I 1×I 2。O 1和O 2为过采样因子。i 1和i 2满足0≤i 1≤(O 1×I 1-1)，0≤i 2≤(O 2×I 2-1)。
可选地，角度向量是均匀线阵(uniform linear array，ULA)的导向矢量。如，
Figure PCTCN2019114491-appb-000010
其中，θ k为角度，k＝1，2，……，K。K表示角度向量的个数；λ为波长，d为天线间距。
其中，导向矢量可以表示一条径的到达角在不同天线的响应存在的相位差。导向矢量a(θ k)与DFT矩阵中的向量
Figure PCTCN2019114491-appb-000011
满足：
Figure PCTCN2019114491-appb-000012
可选地，该角度向量是均匀面阵(uniform plane array，UPA)的导向矢量。该导向矢量例如可以是包含水平角和俯仰角信息的导向矢量。如，
Figure PCTCN2019114491-appb-000013
其中，θ k为水平角，
Figure PCTCN2019114491-appb-000014
为俯仰角；ρ t为第t个发射天线端口的三维坐标，t＝1，2，……，T；u k为第k个角度对应的单位球基矢量：
Figure PCTCN2019114491-appb-000015
下文中为方便说明，将角度向量记作a(θ k)。
在下行传输中，由于加载了角度向量的参考信号可以通过下行信道传输至终端设备，因此，终端设备根据接收到的预编码参考信号测量的信道等效于加载了角度向量的信道。例如，将角度向量a(θ k)加载到下行信道V，可以表示为Va(θ k)。
假设发送设备配置有单极化天线，发射天线端口数为T；频域单元数为N，N≥1，且N为整数。则对于接收设备的一个接收端口来说，基于接收到的参考信号估计的信道可以是一个维度为N×T的矩阵。若基于一个角度向量对参考信号进行空域预编码，则可以将角度向量分别加载到参考信号上。由于角度向量的维度为T×1，故，对于接收设备的一个接收端口来说，基于预编码参考信号估计的信道的维度可以为N×1。并且在每个接收端口、 每个频域单元上，终端设备基于接收到的预编码参考信号估计的信道的维度可以是1×1。
应理解，角度向量是本申请提出的用于表示角度的一种形式。角度向量仅为便于与时延区分而命名，而不应对本申请构成任何限定。本申请并不排除在未来的协议中定义其他名称来表示相同或相似含义的可能。
6、时延向量：也可以称为频域向量。时延向量可用于表示信道在频域的变化规律的向量。如前所述，多径时延导致频率选择性衰落。由傅里叶变换可知，信号在时域上的时间延迟，可以等效到频域的相位渐变。
例如，对于信号g(t)，由傅里叶变换可以将该信号变换到频域上：
Figure PCTCN2019114491-appb-000016
对于信号g(t-t 0)，由傅里叶变换可将该信号变换到频域上：
Figure PCTCN2019114491-appb-000017
其中，ω为频率变量，不同频率对应的相位旋转不同；t和t-t 0表示时延。
该两个时延的信号可以表示为x(t)＝g(t)+g(t-t 0)，由此可以得到频率变量的函数
Figure PCTCN2019114491-appb-000018
令g(ω)≡1，可以得到
Figure PCTCN2019114491-appb-000019
因此，两个不同时延的信号造成了频域选择性衰落。
由于信道在各频域单元的相位变化与时延相关，故可将信道在各频域单元的相位的变化规律通过时延向量来表示。换句话说，该时延向量可用于表示信道的时延特性。
基于时延向量对参考信号进行预编码，实质上可以是指基于时延向量中的元素对频域上各个频域单元进行相位旋转，以通过预编码参考信号来对多径时延造成的频选特性进行预补偿。因此，基于时延向量对参考信号进行预编码的过程可以视为频域预编码的过程。
基于不同的时延向量对参考信号进行预编码，就相当于基于不同的时延向量对信道各个频域单元进行相位旋转。且，同一个频域单元中的不同资源(例如资源元素(resource element，RE))由于加载的时延向量的不同，相位旋转的角度也可以不同。为了区分不同的时延，网络设备可以基于L个时延向量中的每个时延向量分别对参考信号进行预编码。
可选地，时延向量的长度为N，N可以是指用于承载参考信号(如，未经过预编码的参考信号或经过预编码的参考信号)的频域单元数，N≥1，且N为整数。
可选地，L个时延向量中的第l个时延向量可以表示为b(τ l)，
Figure PCTCN2019114491-appb-000020
其中，l＝1，2，……，L；L可以表示时延向量的个数；f 0，f 1，……，f N-1分别表示第1个、第2个至第N个频域单元的载波频率。
可选地，时延向量取自DFT矩阵。如
Figure PCTCN2019114491-appb-000021
该DFT矩阵中的每个向量可以称为DFT向量。
其中，O f为过采样因子，O f≥1；k为DFT向量的索引，并满足0≤k≤O f×N-1或者1-O f×N≤k≤0。
例如，当k＜0时，b(τ l)与DFT矩阵中的向量u k可以满足：
Figure PCTCN2019114491-appb-000022
其中
Figure PCTCN2019114491-appb-000023
Δf＝f n-f n+1，1≤n≤N-1。
下文中为方便说明，将时延向量记作b(τ l)。
在本申请实施例中，为便于理解，以资源块(resource block，RB)作为频域单元的一例来说明对参考信号进行频域预编码的具体过程。当将RB作为频域单元的一例时，可以认为每个频域单元仅包括一个用于承载参考信号的RB。事实上，每个频域单元可以包括一个或多个用于承载参考信号的RB。当每个频域单元中包括多个用于承载参考信号的RB时，网络设备可以将时延向量加载到每个频域单元中用于承载参考信号的多个RB上。
在下行传输中，由于加载了时延向量的参考信号可以通过下行信道传输至终端设备，因此，终端设备根据接收到的预编码参考信号测量的信道等效于加载了时延向量的信道。若基于长度为N的时延向量对参考信号进行频域预编码，则可以将该时延向量中的N个元素分别加载到承载于N个RB上的参考信号上。将时延向量中的第n个元素加载到第n个RB上的信道V (n)上例如可以表示为
Figure PCTCN2019114491-appb-000024
需要说明的是，基于时延向量对参考信号进行频域预编码可以是在资源映射之前执行，也可以是在资源映射之后执行，本申请对此不作限定。
为便于理解，下面结合图2详细说明基于时延向量b(τ l)对参考信号进行预编码的过程。
图2示出了基于时延向量b(τ 1)对N个RB上承载的参考信号进行频域预编码的一例。该N个RB可以包括RB#0、RB#1至RB#N-1。该N个RB中的每个RB上包括一个或多个用于承载该参考信号的RE。例如，用于承载该参考信号的RE可以是每个RB中首个时域符号、首个子载波上的RE。如图中带阴影的方格所示。此情况下，可以对每个RB中的首个时域符号、首个子载波上的RE上加载时域向量b(τ 1)。该N个RB中的每个RB中的首个时域符号、首个子载波上的RE上承载的参考信号可以是对应于同一个端口的参考信号。
假设时延向量
Figure PCTCN2019114491-appb-000025
若将时延向量b(τ 1)加载到N个频域单元上，可以对N个频域单元进行相位旋转。该时延向量中的N个元素可以与该N个频域单元一一对应。例如，该频域向量b(τ 1)中的第0个元素
Figure PCTCN2019114491-appb-000026
可以加载在RB#0上，该频域向量b(τ 1)中的第1个元素
Figure PCTCN2019114491-appb-000027
可以加载在RB#1上，时延向量b(τ 1)中的N-1个元素
Figure PCTCN2019114491-appb-000028
可以加载在RB#N-1上。以此类推，时延向量b(τ 1)中的第n个元素
Figure PCTCN2019114491-appb-000029
可以加载在RB#n上。为了简洁，这里不一一列举。
应理解，RB仅为频域单元的一例，不应对本申请构成任何限定。本申请对于频域单元的具体定义不作限定。
还应理解，时延向量是本申请提出的用于表示时延的一种形式。时延向量仅为便于与角度区分而命名，而不应对本申请构成任何限定。本申请并不排除在未来的协议中定义其他名称来表示相同或相似含义的可能。
另外，假设如网络设备配置有单极化天线，发射天线端口数为T，频域单元数为N。 则对于终端设备的一个接收端口而言，基于接收到的参考信号所估计的信道可以表示为一个维度为N×T的矩阵。若基于L个时延向量对参考信号进行频域预编码，则对于终端设备的一个接收端口而言，基于接收到的预编码参考信号所估计的信道可以表示为一个维度为N×L的矩阵。并且在每个接收端口、每个频域单元上，终端设备基于接收到的预编码参考信号估计的信道的维度可以是1×L。
7、频域单元：频域资源的单位，可表示不同的频域资源粒度。频域单元例如可以包括但不限于，子带(subband)、资源块(RB)、资源块组(resource block group，RBG)、预编码资源块组(precoding resource block group，PRG)等。
在本申请实施例中，网络设备可以基于终端设备的反馈确定与各频域单元对应的预编码矩阵。
8、角度时延对：也可以称为空频向量对。一个角度时延对可以是一个角度向量和一个时延向量的组合。每个角度时延对可以包括一个角度向量和一个时延向量。任意两个角度时延对中所包含的角度向量和时延向量中至少有一项不同。换句话说，每个角度时延对可以由一个角度向量和一个时延向量唯一确定。
在本申请实施例中，基于一个角度向量a(θ k)和一个时延向量b(τ l)对参考信号进行预编码时，用于对参考信号进行预编码的预编码矩阵可以表示为一个角度向量和一个时延向量的共轭转置的乘积，例如可以表示为a(θ k)×b(τ l) H，其维度可以是T×N。或者，用于对参考信号进行预编码的预编码矩阵也可以表示为一个角度向量与一个时延向量的克罗内克尔积(Kronecker)积，例如可以表示为
Figure PCTCN2019114491-appb-000030
其维度可以是T×N。
应理解，上文列举的各种数学表达仅为示例，不应对本申请构成任何限定。例如，用于对参考信号进行预编码的预编码矩阵还可以表示为一个时延向量与一个角度向量的共轭转置的乘积，或，一个时延向量与一个角度向量的克罗内克尔积，其维度可以是N×T。或者，用于对参考信号进行预编码的预编码矩阵还可以表示为上述各种表达的数学变换。为了简洁，这里不一一列举。
在本申请实施例中，一个或多个角度时延对的加权和可以用于确定空频矩阵。基于一个角度时延对所确定的维度T×N为的矩阵可以称为该空频矩阵的一个分量，简称为空频分量矩阵。在下文实施例中，为方便说明，假设由一个角度时延对所确定的维度T×N为的矩阵由a(θ k)×b(τ l) H得到。
9、空频矩阵：在本申请实施例中，空频矩阵是用于确定预编码矩阵的一个中间量。
在本申请实施例中，空频矩阵可以基于接收端口确定，也可以基于传输层确定。如前所述，空频矩阵可以由一个或多个角度时延对的加权和确定，故空频矩阵的维度也可以是N×T。
若空频矩阵基于接收端口确定，则该空频矩阵可以称为与接收端口对应的空频矩阵。与接收端口对应的空频矩阵可用于构建各频域单元的下行信道矩阵，进而可确定与各频域单元对应的预编码矩阵。与某一频域单元对应的信道矩阵例如可以是由各个接收端口对应的空频矩阵中对应于同一频域单元的列向量构造而成的矩阵的共轭转置。如，将各接收端口对应的空频矩阵中的第n个列向量抽取出来，按照接收端口的顺序由左向右排布可得到维度为T×R的矩阵，R表示接收端口数，R≥1且为整数。该矩阵经过共轭转置后可以得到第n个频域单元的信道矩阵V (n)。下文中会详细说明信道矩阵与空频矩阵的关系，这里 暂且省略对二者关系的详细说明。
若空频矩阵基于传输层确定，则该空频矩阵可以称为与与传输层对应的空频矩阵。与传输层对应的空频矩阵可直接用于确定与各频域单元对应的预编码矩阵。与某一频域单元对应的预编码矩阵例如可以是由各个传输层对应的空频矩阵中对应于同一频域单元的列向量构造而成。如，将各传输层对应的空频矩阵中的第n个列向量抽取出来，按照传输层的顺序由左到右排布可得到维度为T×Z的矩阵，Z表示传输层数，Z≥1且为整数。该矩阵可以作为第n个频域单元的预编码矩阵W (n)。
需要说明的是，由本申请实施例提供的信道测量方法所确定的预编码矩阵可以是直接用于下行数据传输的预编码矩阵；也可以经过一些波束成形方法，例如包括迫零(zero forcing，ZF)、最小均方误差(minimum mean-squared error，MMSE)、最大化信漏噪比(signal-to-leakage-and-noise，SLNR)等，得到最终用于下行数据传输的预编码矩阵。本申请对此不作限定。下文中所涉及的预编码矩阵均可以是指基于本申请提供的信道测量方法确定的预编码矩阵。
对空频矩阵与下行信道矩阵、预编码矩阵的关系做简单说明。
空频矩阵是基于信道的频域连续性而提出的一种可用于构建预编码矩阵的中间量。空频矩阵H可满足：H＝SCF H。其中，S表示一个或多个(例如，K个，K为正整数)角度向量构造的矩阵，例如S＝[a(θ 1) a(θ 2) … a(θ K)]，F表示一个或多个(例如，L个，L为正整数)时延向量构造的矩阵，例如F＝[b(τ 1) b(τ 2) … b(τ L)]，C表示与K个角度向量中的每个角度向量和L个时延向量中的每个时延向量对应的加权系数所构成的系数矩阵。C中的每一个元素可以表示所对应的一个角度向量对的加权系数。
在FDD模式下，由于时延和角度的上下行信道互易性，由上行信道测量得到的空频矩阵H UL可以表示为H UL＝SC ULF H，由下行信道测量得到的空频矩阵H DL可以表示为H DL＝SC DLF H。因此，在本申请实施例中，通过下行信道测量来确定和反馈下行信道对应的系数矩阵C DL，便可以确定与下行信道相适配的预编码矩阵。
如前所述，空频分量矩阵被定义为由a(θ k)×b(τ l) H确定，由此可确定空频矩阵H DL的维度为：发射天线端口数×频域单元数。如，下行信道对应的空频矩阵的维度为T×N。在下文实施例中，未作出特别说明的情况下，空频矩阵均是指上文所述的维度为T×N的矩阵H DL。
然而这并不一定是由真实的信道确定的空频矩阵。在通常情况下，信道矩阵的维度被定义为：接收端口数×发射端口数，如，下行信道的维度为R×T。由信道矩阵确定的空频矩阵的维度为N×T，与上述空频矩阵H DL的维度T×N正好相反。因此，本申请实施例中，真实的信道可以是由上述空频矩阵H DL确定的信道矩阵的共轭转置。换言之，由空频矩阵H DL确定的下行信道矩阵可以是真实的信道的共轭转置。
进一步地，由空频矩阵H DL可以确定预编码矩阵。其中，第n个频域单元的预编码矩阵可以是各传输层对应的空频矩阵中的第n个列向量构建。
以对信道矩阵做奇异值分解(singular value decomposition，SVD)为例，由信道矩阵V做SVD可以得到预编码矩阵的共轭转置。而若将信道矩阵做共轭转置后再进行SVD，即，对V H做SVD，则正好可以得到预编码矩阵。因此，本申请实施例中由真实信道的共轭转置所确定的空频矩阵H DL可以直接确定得到与各频域单元对应的预编码矩阵。
再结合上文公式H UL＝SC ULF H来理解空频矩阵与下行信道矩阵的关系。
对H DL＝SC DLF H变形可以得到S HH DL＝C DLF H，进一步变形可以得到(H DL HS) H＝C DLF H，由此可得到系数矩阵C DL＝(H DL HS) HF。其中，H DL H是由真实信道确定的空频矩阵；H DL HS是经过空域预编码后的真实信道。该系数矩阵中C DL的各元素可以分别由(H DL HS) H中的一行与F中的一列相乘确定。换句话说，矩阵系数C DL中的各元素可以由真实信道H DL HS的共轭转置(H DL HS) H中的一行与F中的一列相乘得到，或者说，是由真实信道H DL HS的一列的共轭转置与F的一列相乘得到。
因此，在本申请实施例中，基于终端设备反馈的各角度时延对的加权系数而确定的空频矩阵H DL可以是由真实信道的共轭转置得到。反之，本申请实施例中的空频矩阵也可以是由真实的信道V的共轭转置(即，V H)得到。
应理解，真实的信道与空频矩阵H DL的关系并不是固定不变的。对空频矩阵以及空频分量矩阵的不同定义，可能会使得真实的信道与空频矩阵H DL之间的关系发生变化。例如，空频矩阵H DL可以由真实的信道的共轭转置得到，也可以由真实的信道的转置得到。
当对空频矩阵以及空频分量矩阵的定义不同时，在加载时延和角度时网络设备所执行的操作也有所不同，终端设备在进行信道测量并反馈时所执行的操作也相应地发生变化。但这只是终端设备和网络设备的实现行为，不应对本申请构成任何限定。本申请实施例仅为便于理解，示出了空频矩阵由真实的信道的共轭转置得到的情况。本申请对于信道矩阵的定义、空频矩阵的维度及其定义以及二者间的转换关系不作限定。同理，本申请对于空频矩阵与预编码矩阵间的转换关系也不作限定。
10、天线时延对：可以是一个发射天线端口和一个时延向量的组合。每个天线时延对可以包括一个发射天线端口和一个时延向量。任意两个天线时延对中包含的发射天线端口和/或时延向量不同。换句话说，每个天线时延对可以由一个发射天线端口和一个时延向量唯一确定。应理解，天线时延对可以理解为由一个发射天线端口和一个时延向量确定的空频基本单位的表现形式，但并一定是唯一的表现形式，本申请对于发射天线端口与时延向量的组合的表现形式不作限定。
此外，此外，为了便于理解本申请实施例，作出以下几点说明。
第一，为方便理解，下面对本申请中涉及到的主要参数做简单说明：
T：一个极化方向上的发射天线端口数，T为正整数；
P：一个极化方向上的发射端口数，P为正整数；
R：接收端口数，R为正整数；
Z：传输层数，Z为正整数；
N：用于承载参考信号的频域单元数，N为正整数；
K：角度向量数，K为正整数；
L：时延向量数，L为正整数；
J：发射天线的极化方向数，J为正整数；
第二，在本申请实施例中，为便于描述，在涉及编号时，可以从0开始连续编号。例如，K个角度向量可以包括第0个角度向量至第K-1个角度向量，L个时延向量可以包括第0个时延向量至第L-1个时延向量等，为了简洁，这里不一一列举。当然，具体实现时不限于此。比如也可以从1开始连续编号。例如，K个角度向量可以包括第1个角度向量至第K个角度向量，L个时延向量可以包括第1个时延向量至第L个时延向量等。
应理解，上文所述均为便于描述本申请实施例提供的技术方案而进行的设置，而并非用于限制本申请的范围。
第三，在本申请中，多处涉及矩阵和向量的变换。为便于理解，这里做同一说明。上角标T表示转置，如A T表示矩阵(或向量)A的转置；上角标*表示共轭，如，A *表示矩阵(或向量)A的共轭；上角标H表示共轭转置，如，A H表示矩阵(或向量)A的共轭转置。后文中为了简洁，省略对相同或相似情况的说明。
第四，在下文示出的实施例中，以角度向量和时延向量均为列向量为例来说明本申请提供的实施例，但这不应对本申请构成任何限定。基于相同的构思，本领域的技术人员还可以想到其他更多可能的表现方式。
第五，在本申请中，“用于指示”可以包括用于直接指示和用于间接指示。当描述某一指示信息用于指示A时，可以包括该指示信息直接指示A或间接指示A，而并不代表该指示信息中一定携带有A。
将指示信息所指示的信息称为待指示信息，则具体实现过程中，对待指示信息进行指示的方式有很多种，例如但不限于，可以直接指示待指示信息，如待指示信息本身或者该待指示信息的索引等。也可以通过指示其他信息来间接指示待指示信息，其中该其他信息与待指示信息之间存在关联关系。还可以仅仅指示待指示信息的一部分，而待指示信息的其他部分则是已知的或者提前约定的。例如，还可以借助预先约定(例如协议规定)的各个信息的排列顺序来实现对特定信息的指示，从而在一定程度上降低指示开销。同时，还可以识别各个信息的通用部分并统一指示，以降低单独指示同样的信息而带来的指示开销。例如，本领域的技术人员应当明白，预编码矩阵是由预编码向量组成的，预编码矩阵中的各个预编码向量，在组成或者其他属性方面，可能存在相同的部分。
此外，具体的指示方式还可以是现有各种指示方式，例如但不限于，上述指示方式及其各种组合等。各种指示方式的具体细节可以参考现有技术，本文不再赘述。由上文所述可知，举例来说，当需要指示相同类型的多个信息时，可能会出现不同信息的指示方式不相同的情形。具体实现过程中，可以根据具体的需要选择所需的指示方式，本申请实施例对选择的指示方式不做限定，如此一来，本申请实施例涉及的指示方式应理解为涵盖可以使得待指示方获知待指示信息的各种方法。
此外，待指示信息可能存在其他等价形式，例如行向量可以表现为列向量，一个矩阵可以通过该矩阵的转置矩阵来表示，一个矩阵也可以表现为向量或者数组的形式，该向量或者数组可以由该矩阵的各个行向量或者列向量相互连接而成，等。本申请实施例提供的技术方案应理解为涵盖各种形式。举例来说，本申请实施例涉及的部分或者全部特性，应理解为涵盖该特性的各种表现形式。
待指示信息可以作为一个整体一起发送，也可以分成多个子信息分开发送，而且这些子信息的发送周期和/或发送时机可以相同，也可以不同。具体发送方法本申请不进行限定。其中，这些子信息的发送周期和/或发送时机可以是预先定义的，例如根据协议预先定义的，也可以是发射端设备通过向接收端设备发送配置信息来配置的。其中，该配置信息可以例如但不限于包括无线资源控制信令、媒体接入控制(media access control，MAC)层信令和物理层信令中的一种或者至少两种的组合。其中，无线资源控制信令例如包无线资源控制(radio resource control，RRC)信令；MAC层信令例如包括MAC控制元素(control element，CE)；物理层信令例如包括下行控制信息(downlink control information，DCI)。
第六，本申请对很多特性(例如克罗内克积、信道状态信息(channel state information，CSI)、RB、角度以及时延等)所列出的定义仅用于以举例方式来解释该特性的功能，其详细内容可以参考现有技术。
第七，在下文示出的实施例中第一、第二以及各种数字编号仅为描述方便进行的区分，并不用来限制本申请实施例的范围。例如，区分不同的指示信息等。
第八，“预定义”或“预配置”可以通过在设备(例如，包括终端设备和网络设备)中预先保存相应的代码、表格或其他可用于指示相关信息的方式来实现，本申请对于其具体的实现方式不做限定。其中，“保存”可以是指，保存在一个或者多个存储器中。所述一个或者多个存储器可以是单独的设置，也可以是集成在编码器或者译码器，处理器、或通信装置中。所述一个或者多个存储器也可以是一部分单独设置，一部分集成在译码器、处理器、或通信装置中。存储器的类型可以是任意形式的存储介质，本申请并不对此限定。
第九，本申请实施例中涉及的“协议”可以是指通信领域的标准协议，例如可以包括LTE协议、NR协议以及应用于未来的通信系统中的相关协议，本申请对此不做限定。
第十，“至少一个”是指一个或者多个，“多个”是指两个或两个以上。“和/或”，描述关联对象的关联关系，表示可以存在三种关系，例如，A和/或B，可以表示：单独存在A，同时存在A和B，单独存在B的情况，其中A，B可以是单数或者复数。字符“/”一般表示前后关联对象是一种“或”的关系。“以下至少一项(个)”或其类似表达，是指的这些项中的任意组合，包括单项(个)或复数项(个)的任意组合。例如，a、b和c中的至少一项(个)，可以表示：a，或，b，或，c，或，a和b，或，a和c，或，b和c，或，a、b和c。其中a、b和c分别可以是单个，也可以是多个。
第十一，在本申请实施例中，“当……时”、“在……的情况下”、“若”以及“如果”等描述均指在某种客观情况下设备(如，终端设备或者网络设备)会做出相应的处理，并非是限定时间，且也不要求设备(如，终端设备或者网络设备)在实现时一定要有判断的动作，也不意味着存在其它限定。
第十二，在本申请实施例中，多处提及发射端口和接收端口。为避免引起歧义，作出如下说明：发射端口可以是指发射参考信号(如预编码参考信号等)的端口。接收端口可以是指接收参考信号(如预编码参考信号等)的端口。在本申请实施例中，发射端口可以是网络设备端的端口，接收端口可以是终端设备端的端口。
下面将结合附图详细说明本申请实施例提供的信道测量方法。
应理解，下文仅为便于理解和说明，以终端设备与网络设备之间的交互为例详细说明本申请实施例提供的方法。但这不应对本申请提供的方法的执行主体构成任何限定。例如，下文实施例示出的终端设备可以替换为配置于终端设备中的部件(如芯片或芯片系统)等。下文实施例示出的网络设备也可以替换为配置于网络设备中的部件(如芯片或芯片系统)等。
下文示出的实施例并未对本申请实施例提供的方法的执行主体的具体结构特别限定，只要能够通过运行记录有本申请实施例的提供的方法的代码的程序，以根据本申请实施例提供的方法进行通信即可，例如，本申请实施例提供的方法的执行主体可以是终端设备或网络设备，或者，是终端设备或网络设备中能够调用程序并执行程序的功能模块。
为便于理解，这里先对下文示出的几个实施例做简单说明：
本申请提供了一种基于时域变换的信道测量方法。在每一个接收端口上，终端设备可 以接收到来自一个或多个发射端口的预编码参考信号。终端设备可以基于接收到的每个发射端口的预编码参考信号进行信道估计，并将对应于同一发射端口的多个频域单元上估计所得的信道信息进行时域变换。也就是将信道在频域的变化转换到时域，以获得一个最强的值。终端设备将时域变换所得到的最强反馈给网络设备。终端设备反馈给网络设备的值也就是与同一发射端口对应的加权系数。下文结合图3和图4描述的实施例详细说明了上述基于时域变换的信道测量方法。
本申请另提供了一种基于频域滤波的信道测量方法。在每一个接收端口上，终端设备可以接收到来自一个或多个发射端口的预编码参考信号。终端设备可以基于接收到的每个发射端口的预编码参考信号进行信道估计，并对估计所得的信道信息进行频域滤波。终端设备可以以频域单元组为单位，对同一个频域单元组中的频域单元上的信道信息进行滤波。当同一发射端口的预编码参考信号通过多个频域单元组中的频域单元承载时，终端设备可以将该多个频域单元组中的频域单元上的信道信息经滤波后的结果进行累加。终端设备可以将累加所得的结果反馈给网络设备。终端设备反馈给网络设备的值也就是与同一发射端口对应的加权系数。下文结合图5和图6描述的实施例详细说明了上述基于频域滤波的信道测量方法。
在下文实施例中，网络设备可以基于时延向量和角度向量对参考信号进行预编码，也可以基于时延向量或角度向量对参考信号进行预编码，本申请对此不作限定。
下面，首先结合图3详细说明基于时域变换的信道测量方法。图3是从设备交互的角度示出的本申请实施例提供的信道测量方法300的示意性流程图。图3示出的方法300可以包括步骤310至步骤340。下面详细说明方法300中的各步骤。
为了便于理解，下文中以一个极化方向的发射天线发送的预编码参考信号为例，详细说明终端设备进行信道测量和反馈的过程。该一个极化方向的发射天线可以是网络设备所配置的J个极化方向的发射天线中任意一个极化方向的发射天线。本申请对于网络设备所配置的发射天线的极化方向数J不作限定。
在步骤310中，终端设备接收预编码参考信号。相对应地，网络设备发送预编码参考信号。
在本实施例中，网络设备可以基于K个角度向量和L个时延向量对参考信号进行预编码。由该K个角度向量和L个时延向量可以得到多种角度向量和时延向量的组合。任意两种组合中的角度向量和/或时延向量不同。每种组合中的角度向量和时延向量可用于对参考信号进行预编码，以得到对应于一个端口的预编码参考信号。因此，网络设备基于K个角度向量和L个时延向量预编码得到的预编码参考信号可以对应于一个或多个端口，每个端口的预编码参考信号可以是基于K个角度向量中的一个角度向量和L个时延向量中的一个时延向量对参考信号进行预编码得到。或者说，每个端口的预编码参考信号可以是基于一种角度向量和时延向量的组合对参考信号进行预编码得到。
在一种可能的实现方式中，网络设备可以将K个角度向量中的每个角度向量和L个时延向量中的每个时延向量两两组合，得到角度向量和时延向量的K×L种组合，或者说，得到K×L个角度时延对。也就是说，网络设备可以基于K个角度向量中的每个角度向量以及L个时延向量中的每个时延向量对参考信号进行预编码。网络设备在基于K个角度向量中的第k(1≤k≤K，k为整数)个角度向量对参考信号进行预编码时，可以遍历L个时延向量中的每个时延向量对参考信号进行预编码；或者，网络设备在基于L个时延向量 中的第l(1≤l≤L，l为整数)个时延向量对参考信号进行预编码时，可以遍历K个角度向量中的每个角度向量对参考信号进行预编码。换句话说，该K个角度向量对每个时延向量来说可以认为是共用的，该L个时延向量对每个角度向量来说也可以认为是共用的。或者说，该K个角度向量和L个时延向量是相互共用的。
在另一种可能的实现方式中，网络设备在基于K个角度向量中的第k个角度向量对参考信号进行预编码时，可以遍历与第k个角度向量对应的L k(1≤L k≤L，L k为整数)个时延向量中的每个时延向量对参考信号进行预编码。上述L个时延向量中的L可以满足：
Figure PCTCN2019114491-appb-000031
在这种实现方式中，至少两个角度向量对应的时延向量不同。
这里，至少两个角度向量对应的时延向量不同，可以是指，K个角度向量中，至少有两个角度向量对应的时延向量不同，其他角度向量分别对应的时延向量可以相同，也可以不同，本申请对此不作限定。换句话说，各角度向量对应的时延向量部分或全部不同。
其中，两个角度向量对应的时延向量不同，可以是指，两个角度向量对应的时延向量完全不同，即，两个角度向量对应的时延向量没有重复，或者说，没有交集。例如，角度向量a(θ 1)对应的时延向量包括b(τ 2)，角度向量a(θ 2)对应的时延向量包括b(τ 1)和b(τ 3)。两个角度向量对应的时延向量不同，也可以是指，两个角度向量对应的时延向量部分不同，即，两个角度向量对应的时延向量有部分重复，但不完全相同，或者说，两个角度向量对应的时延向量有交集，但不完全相同。例如，a(θ 1)对应的时延向量包括b(τ 2)和b(τ 3)，角度向量a(θ 2)对应的时延向量包括b(τ 1)和b(τ 3)。
当K个角度向量中任意两个角度向量对应的时延向量互不重复时，
Figure PCTCN2019114491-appb-000032
当K个角度向量中两个或两个以上的角度向量对应的时延向量中有部分重复时，
Figure PCTCN2019114491-appb-000033
因此，网络设备可以由上述K个角度向量和L个时延向量，得到
Figure PCTCN2019114491-appb-000034
种角度向量和时延向量的组合。
在又一种可能的实现方式中，网络设备在基于L个时延向量中的第l个时延向量对参考信号进行预编码时，可以遍历与第l个时延向量对应的K l(1≤K l≤K，K l为整数)个角度向量中的每个角度向量对参考信号进行预编码。上述K个角度向量中的K可以满足：
Figure PCTCN2019114491-appb-000035
在这种实现方式中，至少两个时延向量对应的角度向量不同。
这里，至少两个时延向量对应的角度向量不同，可以是指，L个时延向量中，至少有两个时延向量对应的角度向量不同，其他时延向量分别对应的角度向量可以相同，也可以不同，本申请对此不作限定。换句话说，各时延向量对应的角度向量部分或全部不同。
其中，两个时延向量对应的角度向量不同，可以是指，两个时延向量对应的角度向量完全不同，即，两个时延向量对应的角度向量没有重复，或者说，没有交集。例如，时延向量b(τ 1)对应的角度向量包括a(θ 2)，时延向量b(τ 2)对应的角度向量包括a(θ 1)。两个时延向量对应的角度向量不同，也可以是指，两个时延向量对应的角度向量部分不同，即，两个时延向量对应的角度向量有部分重复，但不完全相同，或者说，两个时延向量对应的角度向量有交集，但不完全相同。例如，时延向量b(τ 1)对应的角度向量包括a(θ 2)，时延向量b(τ 2)对应的角度向量包括a(θ 1)和a(θ 2)。当L个时延向量中任意两个时延向量对应 的角度向量互不重复时，
Figure PCTCN2019114491-appb-000036
当L个时延向量中两个或两个以上时延向量对应的角度向量有部分重复时，
Figure PCTCN2019114491-appb-000037
因此，网络设备可以由上述K个角度向量和L个时延向量，得到
Figure PCTCN2019114491-appb-000038
种角度向量和时延向量的组合。
应理解，上文仅为便于理解，列举了角度向量与时延向量的对应关系，但这不应对本申请构成任何限定。本申请对于角度向量与时延向量的对应关系不作限定。
可以理解的是，若网络设备基于K个角度向量和L个时延向量对参考信号进行预编码，所发射的预编码参考信号的端口数可以是K个角度向量和L个时延向量所确定的组合数。即，发射端口数P可以由K个角度向量和L个时延向量所确定的组合数确定。在上述几种不同的实现方式中，P的值不同，例如，P＝K×L，或者，
Figure PCTCN2019114491-appb-000039
或者，
Figure PCTCN2019114491-appb-000040
由于角度和时延具有上下行信道互易性，可选地，该K个角度向量和L个时延向量均可以是基于上行信道测量确定。
具体地，网络设备可以根据预先估计得到的上行信道矩阵，确定K个角度和L个时延。该K个角度可以通过K个角度向量来表征。该L个时延可以通过L个时延向量来表征。该上行信道矩阵可以是由该K个角度向量和L个时延向量所确定的若干个空频分量矩阵的加权和。
其中，该K个角度向量例如可以是从预先定义的角度向量集合中确定的较强的K个角度向量。该K个角度向量可以是针对L个时延向量共同确定，也可以是针对L个时延向量中的每个时延向量分别确定。本申请对此不作限定。可选地，该角度向量集合中的各角度向量取自DFT矩阵。该K个角度向量例如可通过对上行信道矩阵进行DFT确定。可选地，该角度向量集合中的各角度向量为导向矢量。
该L个时延向量例如可以是从预先定义的时延向量集合中确定的较强的L个时延向量。该L个时延向量可以是针对K个角度向量共同确定，也可以是针对K个角度向量中的每个角度向量分别确定。本申请对此不作限定。可选地，该时延向量集合中的各时延向量取自DFT矩阵。该L个时延向量例如可通过对上行信道矩阵进行DFT确定。
网络设备例如可以利用现有技术中的角度和时延联合估计(joint angle and delay estimation，JADE)算法来确定该K个角度向量和与每个角度向量对应的较强的一个或多个时延向量。具体地，该估计算法例如可以是多重信号分类算法(multiple signal classification algorithm，MUSIC)、巴特利特(Bartlett)算法或旋转不变子空间算法(estimation of signal parameters via rotation invariant technique algorithm，ESPRIT)等。网络设备也可以通过对基于上行信道测量确定的空频矩阵进行DFT来确定K个角度向量和L个时延向量。本申请对于网络设备确定该K个角度向量和L个时延向量的具体方法不作限定。
以对空频矩阵做DFT为例，假设该角度向量和时延向量均取自DFT矩阵。预先定义的角度向量集合例如可以是由空域DFT矩阵中的多个向量构成的向量集合。为便于区分，将该向量集合称为角度向量集合U s，U s＝[u s,1 u s,2 … u s,T]。预先定义的时延向量集合例如可以是由频域DFT矩阵中的多个向量构成的向量集合。为便于区分，将该向量集 合称为时延向量集合U f，U f＝[u f，1 u f，2 … u f,N]。
网络设备可以通过信道估计确定上行信道，进而确定上行信道的空频矩阵H UL。网络设备可以将上行信道估计得到的空频矩阵H UL做空域和频域的DFT变换，得到系数矩阵C UL如下：C UL＝U s HH ULU f。为方便理解，这里将上行信道的空频矩阵H UL的维度与下行信道的空频矩阵的维度H DL保持一致。前文中已经描述了下行信道的空频矩阵的维度以及与下行信道的关系，由上行信道确定的空频矩阵H UL的维度可以是N×T。
应理解，这里示出的上行信道的空频矩阵H UL的维度以及用于确定系数矩阵C UL的计算式仅为示例，不应对本申请构成任何限定。对于空频矩阵H UL定义不同的维度，用于确定系数矩阵C UL的计算式也不同。
网络设备可以从该系数矩阵C UL中确定较强的K个行。该较强的K个行可用于确定K个角度向量。例如，若P＝K×L，网络设备可以根据该系数矩阵C UL中各行元素的模的平方和的大小，确定模的平方和较大的K个行。该模的平方和较大的K个行可用于确定K个角度向量。该K个行在系数矩阵C UL中的位置可用于确定K个角度向量在上述角度向量集合中的位置。如，该K个行在系数矩阵C UL中的行序号可以是K个角度向量在角度向量集合中的列序号。由此可以确定K个角度向量。该K个角度向量也就是角度向量集合中被选择用来对下行参考信号做预编码的角度向量。
网络设备可以从该系数矩阵C UL中确定较强的L个列。各该较强的L个列可用于确定L个时延向量。例如，网络设备可以根据系数矩阵C UL中各列元素的模的平方和的大小，确定模的平方和较大的L个列。该模的平方和较大的L个列可用于确定L个时延向量。该L个列在系数矩阵C UL中的位置可用于L个时延向量在上述时延向量集合中的位置。如，该L个列在系数矩阵C UL中的列序号可以是L个时延向量在时延向量集合中的列序号。由此可以确定L个时延向量。该L个时延向量也就是时延向量集合中被选择用来对下行参考信号做预编码的时延向量。
网络设备也可以根据系数矩阵C UL中较强的K个行中的每一行，确定较强的一个或多个时延向量。例如，若
Figure PCTCN2019114491-appb-000041
对于该K个行中的第k个行，网络设备可以根据各元素的模的平方，确定模的平方大于预设值的一个或多个元素，例如，L k个。该预设值例如可以是预定义值。如，可以是此列元素的模的平方和的80％。模的平方大于预设值的L k个元素可用于确定L k个时延向量。例如，模的平方大于预设值的L k个元素在系数矩阵C UL中所处的列可用于确定L k个时延向量在预先定义的时延向量集合中的位置。如，该L k个元素在系数矩阵C UL中的列序号可以是L k个时延向量在时延向量集合中的列序号。对于K个角度向量，时延向量的总数可以为L。L个时延向量也就是时延向量集合中被选择的时延向量。
网络设备还可以根据系数矩阵C UL中较强的L个列中的每一列，确定较强的一个或多个角度向量。例如，若
Figure PCTCN2019114491-appb-000042
对于该L个行中的第l个行，网络设备可以根据各元素的模的平方，确定模的平方大于预设值的一个或多个元素，例如，K l个。网络设备针对每个时延向量确定对应的角度向量的过程如上文基于每个角度向量确定对应的时延向量的过程相似，为了简洁，这里不再赘述。
应理解，上文仅为便于理解，列举了可用于网络设备确定K个角度向量和L个时延向量的几种可能的方法。但这不应对本申请构成任何限定。本申请对于网络设备确定该K 个角度向量和L个时延向量的具体实现方式不作限定。
此外，上行信道矩阵例如可以是由网络设备根据预先接收到的上行参考信号，如SRS，估计得到，或者根据正确解码之后的数据信号得到，本申请对此不作限定。网络设备根据上行参考信号估计上行信道矩阵的具体方法可以参考现有技术，为了简洁，这里省略对该具体方法的详细说明。由于在FDD模式下，上下行信道的角度和时延可互易，则可以将上行信道测量所得的K个角度向量和L个时延向量加载至下行参考信号，以便终端设备基于接收到的预编码参考信号进行下行信道测量。当然，也可以将上行信道测量所得的K个角度向量加载至下行参考信号，或者，也可以将上行信道测量所得的L个时延向量加载至下行参考信号。本实施例主要详细说明将K个角度向量和L个时延向量加载至下行参考信号的情况。
应理解，基于上行信道测量确定上述K个角度向量和L个时延向量并不是唯一的实现方式。该K个角度向量和L个时延向量例如可以是预先定义，如协议定义；或者，也可以是由网络设备基于此前的一次或多次下行信道测量统计确定。本申请对于K个角度向量和L个时延向量的获取方式不作限定。
还应理解，该K个角度向量和L个时延向量也并不一定基于上行信道测量确定。例如，该K个角度向量和L个时延向量可以是预定义的，如协议定义；或者，该K个角度向量和L个时延向量可以是基于此前的一次或多次下行信道测量而反馈的结果统计确定。本申请对于K个角度向量和L个时延向量的确定方式不作限定。
网络设备基于该K个角度向量和L个时延向量对下行参考信号进行预编码所得到的预编码参考信号，可以通过预先配置的参考信号资源来传输。可选地，该下行参考信号为CSI-RS，该参考信号资源为CSI-RS资源。该参考信号资源可以包括多个频域单元，如N个频域单元。也就是说，每个发射端口的预编码参考信号可以承载N个频域单元上。该N个频域单元在用于承载P个发射端口的预编码参考信号时，例如可以通过频分复用(frequency division duplexing，FDD)、时分复用(time division duplexing，TDD)、码分复用(code division duplexing，CDD)等方式来区分不同的发射端口。本申请对此不作限定。
在步骤320中，终端设备生成第一指示信息，该第一指示信息用于指示对应于P个发射端口的P组加权系数。
终端设备可以基于接收到的预编码参考信号进行信道估计，并基于估计所得的信道信息生成第一指示信息。该第一指示信息可用于指示对应于P个发射端口的P组加权系数。其中，每组加权系数可以包括一个或多个加权系数。
在本申请实施例中，终端设备可以基于接收端口反馈对应于P个发射端口的P组加权系数。该第一指示信息所指示的对应于P个发射端口的P组加权系数中，每组加权系数可以包括一个或多个加权系数。例如，每组加权系数可以包括R’个加权系数。1≤R’≤R，且R’为整数。
可选地，R’＝1。即，每组加权系数包括一个加权系数。该加权系数可以是基于R个接收端口上接收到的预编码参考信号进行信道估计所得的信道信息经时域变换后加权得到，或加权后进行时域变换得到；也可以是基于R个接收端口中的某一个接收端口上接收到的预编码参考信号进行信道估计所得的信道信息经时域变换后得到；还可以是基于一个接收端口(即，R＝1)上接收到的预编码参考信号进行信道估计所得的信道信息经时域变换得 到。
可选地，R’＝R。即，每组加权系数也可以包括R个加权系数。例如，该R个加权系数与R个接收端口对应，每个加权系数是基于一个接收端口上接收到的预编码参考信号进行信道估计所得的信道信息经时域变换后得到。
可选地，R’＜R。即，每组加权系数包括的加权系数少于R个。例如，接收端口数为多个(即，R＞1)，而R’个加权系数中的一个或多个可以是基于部分接收端口上接收到的预编码参考信号进行信道估计所得的信道信息经时域变换后加权得到，或加权后进行时域变换得到。
终端设备也可以基于传输层反馈对应于P个发射端口的P组加权系数。每组加权系数可以包括Z个加权系数，与Z个传输层对应。需要说明的是，与Z个传输层对应的加权系数也可以是基于每个接收端口接收到的预编码参考信号进行信道估计所得的信道信息经时域变换得到的结果确定。后文中会详细说明如何基于传输层确定P组加权系数的具体过程，这里暂且省略。
对于P个发射端口中的任意一个发射端口，如第p个发射端口，p可以在0至P-1中任意取整数值，终端设备可以通过执行以下流程来确定与第p个发射端口对应的加权系数。
在0至R-1范围内对r遍历取值，反复执行以下步骤i和步骤ii，以确定与第p个发射端口与第r个接收端口对应的加权系数：
步骤i、基于在第r个接收端口上接收到的第p个发射端口的预编码参考信号进行信道估计，得到分别对应于N个频域单元的信道信息；
步骤ii、对上述步骤i中确定的分别对应于N个频域单元的信道信息进行时域变换，将经时域变换得到的N个值中的第n p,r个值确定为与第p个发射端口和第r个接收端口对应的加权系数。
在0至P-1范围内对p遍历取值，反复执行以上流程，便可以得到对应于P个发射端口的P组加权系数。
下面详细说明终端设备基于接收端口反馈加权系数时，确定与P个发射端口对应的P组加权系数的过程。
为便于理解，首先假设R＝1，即，每组加权系数可以包括一个加权系数。每个发射端口的预编码参考信号可以通过N个RB(即，频域单元的一例)来承载。此情况下，对应于每个发射端口的一组加权系数可以包括一个加权系数。该第一指示信息可用于指示对应于P个发射端口的P个加权系数。
由于终端设备能够识别的发射端口是与预编码参考信号对应的端口，故终端设备可以基于接收到的每个发射端口的预编码参考信号来进行信道估计。
若不考虑对参考信号做预编码，对于每个接收端口来说，该终端设备基于接收到的预编码参考信号所估计的下行信道的维度可以是N×T。在每个RB上接收到的下行信道的维度可以是1×T。由于网络设备基于角度向量和时延向量对参考信号进行了预编码，每个角度向量的维度可以为T×1，则经过角度向量和时延向量对参考信号进行预编码后，终端设备在每个接收端口、每个RB上接收到的下行信道的维度可以是1×1。该维度为1×1的下行信道也就是在一个RB上基于预编码参考信号进行信道估计得到的信道信息。可选地，该信道信息具体可以是基于接收到的预编码参考信号进行信道估计而得到的信道估计值。 可以理解，该信道估计值具体可以是等效信道信息，即，加载了预编码的信道信息。
由于网络设备基于K个角度向量和L个时延向量对参考信号进行了预编码，则每个RB承载的预编码参考信号可以对应一个或多个发射端口，如上文所述的P个发射端口。该P个发射端口可以与P个角度时延对具有一一对应关系。其中，该P个发射端口中的第p个发射端口所对应的预编码参考信号例如可以是基于上述K个角度向量中的第k个角度向量和L个时延向量中的第l个时延向量对参考信号进行预编码得到。即，第p个发射端口与第k个角度向量和第l个时延向量对应。换句话说，第p个发射端口对应的预编码参考信号可以用于确定第k个角度向量和第l个时延向量构成的角度向量的加权系数，也就是，可用于确定第p个角度时延对的加权系数。因此，上文所述的与第p个发射端口对应的加权系数也就是第p个角度时延对的加权系数。
以下，不失一般性，详细说明终端设备确定与第p个发射端口对应的加权系数的过程。
对于该第p个发射端口的预编码参考信号，终端设备可以基于在一个接收端口、N个RB上接收到的预编码参考信号进行信道估计得到的信道估计值确定第p个角度时延对的加权系数。该第p个角度时延对的加权系数可以由该N个RB上的N个信道估计值确定。
假设终端设备基于第n个RB上接收到的第p个发射端口的预编码参考信号进行信道估计所得到的信道估计值记为
Figure PCTCN2019114491-appb-000043
则终端设备基于第p个发射端口的预编码参考信号进行信道估计所得到的信道估计值可以记为：
Figure PCTCN2019114491-appb-000044
共N个信道估计值。可以看到，该N个信道估计值与N个RB对应，也就是与N个频域单元对应。故该N个信道估计值可以表征信道在频域的变化。由于该N个信道估计值是基于第p个发射端口的预编码参考信号进行信道估计确定，因此该N个信道估计值是与第p个角度时延对对应的信道估计值。
如前所述，空频矩阵H DL满足H DL＝SC DLF H。在本申请实施例中，H DL的维度可以是T×N；角度向量可以为K个，每个角度向量的长度可以是T，则S的维度可以是T×K；每个时延向量可以为L个，每个时延向量的长度可以是N，则F的维度可以是N×L。对上式变形可以得到：S HH DL＝C DLF H，进一步可以得到(H DL HS) H＝C DLF H。对(H DL HS) H＝C DLF H进一步变形，可以得到系数矩阵C DL＝(H DL HS) HF。
当网络设备基于K个角度向量对参考信号进行空域预编码时，也就是将真实的信道右乘S，得到H DL HS。H DL HS是经过空域预编码后的真实信道。在本申请实施例中，其维度可以是N×K。当网络设备基于L个时延向量对空域预编码后的参考信号做频域预编码时，可以通过(H DL HS) HF来表示。在本申请实施例中，其维度可以是K×L。
该系数矩阵中C DL的各元素可以分别由(H DL HS) H中的一行与F中的一列相乘确定。换句话说，矩阵系数C DL中的各元素可以由真实信道H DL HS的共轭转置的一行与F中的一列相乘得到。
如，系数矩阵C DL中的第l行第k列的元素为( H DL HS) H中的第l行和F中的第k列相乘得到。系数矩阵C DL中的第l行第k列的元素也就是与第k个角度向量和第l个时延向量对应的加权系数。
由矩阵乘法运算可以知道，(H DL HS) H中的每个行向量包括的元素数与F中每个列向量包括的元素数相同。在本实施例中，(H DL HS) H中的每个行向量包括的元素数与F中每个列向量包括的元素数均可以为N。当行向量与列向量相乘时，需要将行向量中的各元素(如 第n个元素，n在1至N中遍历取值)分别与列向量中的相应元素(如第n个元素，n在1至N中遍历取值)相乘后再求和，而(H DL HS) H中的每一行中的N个元素与N个频域单元(如RB、子带等)对应。然而，网络设备并不能预先获知下行信道在各个频域单元(如RB)之间的相关性，故无法在网络设备侧完成(H DL HS) HF的运算，而仅仅是将各时延向量中的元素加载到下行信道的各个RB上。
为便于理解，这里假设K个角度向量和L个时延向量均被加载在N个RB中的每个RB上。将上文中C DL＝(H DL HS) HF进一步变形可以得到：C DL＝(F HH DL HS) H＝(F HH DL'S) H。其中，H DL'表示由真实的下行信道确定的空频矩阵，由于真实的信道维度为R×T，故H DL'的维度为N×T。该H DL'可以包括N个维度为1×T的行向量，如包括h 0，h 1至h N-1，分别对应于N个RB中的第0个至第N-1个RB。
可以理解，本申请实施例中定义的空频矩阵H DL与上文中由真实信道确定的空频矩阵H DL'间满足H DL'＝H DL H。这是由于本申请中定义的空频矩阵H DL是由真实信道的共轭转置确定的。
在加载了L个角度向量和K个时延向量之后，终端设备基于在一个接收端口接收到的预编码参考信号而估计的信道可以表示为：
Figure PCTCN2019114491-appb-000045
其中，b(τ 0)至b(τ L-1)可以表示F中的L个时延向量；b(τ 0) n可以表示b(τ 0)中的N个元素中的第n个元素，b(τ L-1) n可以表示b(τ L-1)中的N个元素中的第n个元素，n＝0，1，……，N-1；S可以表示由K个角度向量构造的维度为T×K的矩阵。因此，b(τ l) n Hh nS(n＝0，1，……，N-1；l＝0，1，……，L-1)可以是维度为1×K的行向量。
也就是说，矩阵
Figure PCTCN2019114491-appb-000046
中的第n行，可以表示基于在第n个RB上接收到的多个端口的预编码参考信号进行信道估计得到的信道估计值。矩阵
Figure PCTCN2019114491-appb-000047
中的每行可以包括K×L个元素，可分别对应于K×L个端口，或者说，K×L个角度时延对。
由于终端设备接收到的预编码参考信号经历了下行信道，是能够获知下行信道在各个RB之间的相关性的，可以完成上述求和操作。即，将矩阵
Figure PCTCN2019114491-appb-000048
中的每一列元素分别求和。也就是，将
Figure PCTCN2019114491-appb-000049
中对应于同一时延向量和同一角度向量的元素求和，可以得到：(b(τ 0) HH DL'S … b(τ L-1) HH DL'S) H。对于每个时延向量和每个角度向量，或者说，对于每个发射端口，上述运算可以理解为对N个RB上的信道估计值求和。
其中，b(τ l) HH DL'S(l＝1，2，……，L)可以是一个维度为1×K的的行向量，对应于L个时延向量中的第l个时延向量。该行向量中的第k个元素可对应于K个角度向量中的第k个角度向量。因此，b(τ l) HH DL'S中的第k个元素可对应于上文所述的基于第p个端口的预编码参考信号进行信道估计得到的下行信道的估计值y n p。
将(b(τ 1) HH DL'S … b(τ L) HH DL'S) H重排后便可以得到维度为K×L的系数矩阵C DL，
Figure PCTCN2019114491-appb-000050
该系数矩阵C DL中的第k行第l列的元素与第k个角度向量和第l个时延向量对应，也就是，对应于由第k个角度向量和第l个时延向量构成的角度时延对的加权系数。
因此，终端设备可以通过对N个RB的信道估计值求和，确定与各角度向量和时延向量组合得到的各角度时延对对应的加权系数。其中N个RB是参考信号资源中的N个频域单元，因为分布在参考信号资源的频域资源上，也可以理解为为是参考信号资源的全带。
基于上述说明，可以通过对与第p个角度时延对对应的N个信道估计值累加求和，得到与第p个角度时延对对应的加权系数。然而，网络设备在基于时延向量对参考信号进行预编码时，是将时延向量中的N个不同元素分别加载在同一个发射端口所对应的N个RB上的。因此终端设备在每个RB上估计得到的信道估计值可能是不连续的。如果将该N个信道估计值直接累加求和的值作为第p个角度时延对的加权系数反馈，由此而恢复的下行信道可能也与真实的信道具有较大的差异，由此而确定的用于下行数传的预编码矩阵也就不能够与真实的信道很好地匹配，因此影响系统传输性能。
在本申请实施例中，终端设备可以通过对该N个信道估计值进行时域变换，将频域的信道转换到时域，通过时域变换所得到的值来表征该第p个角度时延对的加权系数。
在一种实现方式中，终端设备可以将该N个信道估计值所构造的向量进行时域变换。经时域变换可得到N个值(为方便说明，以下简称时域变换值)。终端设备可以将该N个时域变换值中的某一个值(例如第n p个值)作为与该第p个角度时延对对应的加权系数来反馈。
之所以可以将N个时域变换值中的一个值作为与角度时延对对应的加权系数来反馈，是因为若对该N个信道估计值进行了时域变换，如进行了IFFT，在上下行不存在时延偏差的情况下，所得的N个时域变换值中的直流分量(即，该N个时域变换值中的第0个值)正好等于基于N个频域单元上接收到的预编码参考信号估计所得的N个信道估计值累加所得的总和。由于该N个信道估计值分别是基于N个频域单元上接收到的参考信号估计得到，故该N个信道估计值累加所得的总和可以理解为是对N个频域单元的频域累加所得的总和。
例如，若基于时延向量b(τ 1)和b(τ 2)对参考信号进行预编码，终端设备针对其中的一个端口(如与b(τ 1)对应的端口)所反馈的系数可以表示为：
Figure PCTCN2019114491-appb-000051
其中h n表示第n个频域单元的信道估计值，l取值为1和2。
式中，各叠加项分别为：
Figure PCTCN2019114491-appb-000052
Figure PCTCN2019114491-appb-000053
代入上式可以得到：
Figure PCTCN2019114491-appb-000054
Figure PCTCN2019114491-appb-000055
由于基底是正交的，经相乘为0。因此，上式中c＝Nα 1。
由上文推导可以看到，经IFFT得到的N个时域变换值中的第0个值(即，直流分量)Nα 1正好等于基于N个信道估计值的累加和。
下面详细说明终端设备通过对N个信道估计值进行时域变换来确定第p个角度时延对的加权系数的具体过程。
若将该N个信道估计值记为一个向量，则该向量可以表示第p个发射端口的预编码参考信号所估计的信道向量。该向量例如可以表示为：
Figure PCTCN2019114491-appb-000056
或，
Figure PCTCN2019114491-appb-000057
在本实施例中，为方便说明，将该N个信道估计值所构成的信道向量记为
Figure PCTCN2019114491-appb-000058
可选地，时域变换包括IFFT或IDFT。以IFFT为例，将上述与信道向量
Figure PCTCN2019114491-appb-000059
进行IFFT可以得到N个时域变换值。终端设备可以将该N个时域变换值中的某一个值确定为与第p个角度时延对对应的加权系数。
假设终端设备可以将该N个时延变换值中的第n p个值确定为与第p个角度时延对对应的加权系数。例如由IFFT得到的与第p个角度时延对对应的加权系数c p可以表示为：
Figure PCTCN2019114491-appb-000060
即，与第k个角度向量和第l个时延向量对应的加权系数c k,l可以表示为：
Figure PCTCN2019114491-appb-000061
上述n p的值例如可以是预定义的，如协议预定义，也可以是终端设备自行确定的，还可以是网络设备指示的，本申请对此不作限定。可以理解，0≤n p≤N-1，且n p为整数。
可选地，n p为预定义值。示例性地，n p为0。换句话说，终端设备可以将N个时域变换值中的第0个值作为第p个角度时延对对应的加权系数。
应理解，n p为0仅为一种可能的实现方式，不应对本申请构成任何限定。例如在上下行定时有偏差的情况下，n p也可能为其他取值，例如可以预先根据经验值确定，或者协议预定义等。本申请对此不作限定。
可选地，n p由终端设备确定。可选地，上述第一指示信息指示n p的值。
例如，终端设备可以从该N个时域变换值中选择一个最大值作为该第p个角度时延对对应的加权系数。
可选地，n p为网络设备确定。可选地，在步骤320之前，该方法还包括：终端设备接收第四指示信息，该第四指示信息用于指示n p的值。相对应地，网络设备发送该第四指示信息。
应理解，上文所列举的对n p的值的确定或指示仅为示例，不应对本申请构成任何限定。
终端设备将N个时域变换值中的某一个值作为第p个角度时延对的加权系数的具体过程例如可以通过滤波来实现。例如，将上述N个时域变换值所构成的向量乘以滤波系数，以得到该第p个角度时延对的加权系数。该滤波系数可以包括N个元素，例如可以记为维度为1×N的向量，或维度为N×1的向量。为便于区分，将该滤波系数中的N个元素构成的向量称为滤波系数向量。该滤波系数包括的N个元素可以包括N-1个零元素和1个非零元素，该非零元素可以是该N个元素(或者说，维度为1×N的滤波系数向量或维度为N×1的滤波系数向量)中的第n p个元素。
上述N个时域变换值例如可以构成维度为N×1的向量，或维度为1×N的向量。为便于区分，例如称为时域变换向量。
终端设备可以将维度为N×1的时域变换向量左乘一个维度为1×N的滤波系数向量，或者，也可以将维度为1×N的时域变换向量右乘一个维度为N×1的滤波系数向量，从而得到与第p个角度时延对对应的加权系数。
举例而言，上述N个时域变换值例如可以构成维度为N×1的时域变换向量。假设上述n p的值为0，则该滤波系数构成的滤波系数向量可以记为[1 0 … 0] 1×N。则对该N个时域变换至进行滤波，可以通过将上述维度为N×1的时域变换向量左乘滤波系数向量[1 0 … 0] 1×N来实现。由此，可以得到该N个时域变换值中的第0个值。
应理解，这里所列举的滤波系数仅为一种可能的形式，不应对本申请构成任何限定。由于滤波的具体过程可以参考现有技术，为了简洁，这里不再一一举例说明。还应理解，滤波仅为一种可能的实现方式，不应对本申请构成任何限定。本申请对于终端设备从N个时域变换值中选择某一个值的具体实现方式不作限定。
还应理解，上文对各向量的命名仅为便于区分和说明，不应对本申请构成任何限定。
上文中仅为便于理解，以R＝1为例，详细说明了终端设备确定与第p个发射端口对应的加权系数的具体过程。但这不应对本申请构成任何限定。接收端口数R可以为1，也可以大于1。当R＞1时，该终端设备可以基于每个接收端口、每个RB上接收到的第p个发射端口的预编码参考信号确定与第p个发射端口对应的一组加权系数。
假设与第p个发射端口对应的一组加权系数包括R个加权系数，则该R个加权系数可以与R个接收端口对应。其中第r个加权系数可以是基于第r个接收端口、N个RB上接收到的第p个发射端口的预编码参考信号确定。r可以在0至R-1中任意取整数值。对于r的任意取值，终端设备均可以按照上文所述的方法来确定一个加权系数。从而可以得到与第p个发射端口、R个接收端口对应的R个加权系数。
示例性地，对于第r个接收端口、第p个发射端口，终端设备可以将N个时域变换值中的第n p,r个值确定为与第r个接收端口、第p个发射端口对应的加权系数，也就是第p个角度时延对对应的加权系数中的第r个系数。
可选地，该方法还包括：对第p个发射端口与第r个接收端口间的信道信息所确定的向量进行时域变换，得到变换后的向量，该向量中的第n p,r个值是与第p组加权系数中的第r个加权系数。
如前所述，终端设备将N个时域变换值中的某一个值作为第p个角度时延对的加权系数的具体实现例如可以通过滤波实现。当R＞1时，对于r任意取值，终端设备可以将对 应于第r个接收端口、第p个发射端口对应的N个时域变换值所构成的向量乘以滤波系数，以得到该第p个角度时延对的一个加权系数，该加权系数可以与第r个接收端口对应。
其中，该滤波系数可以包括N个元素，例如，可以记为维度为1×N的向量，或维度为N×1的向量。与上文所述相对应，该向量可以称为滤波系数向量。该滤波系数所包括的N个元素中可以包括N-1个零元素和1个非零元素，该非零元素可以是该N个元素(或者说，维度为1×N的滤波系数向量或维度为N×1的滤波系数向量)中的第n p,r个元素。
在确定了滤波系数向量之后，终端设备可以基于上文所述相同的方式来确定对应于第r个接收端口、第p个发射端口的加权系数。在0至R-1的范围内对r遍历取值，便可以得到对应于R个接收端口、第p个发射端口的R个加权系数，即，对应于第p个发射端口的一组加权系数。
应理解，滤波仅为一种可能的实现方式，不应对本申请构成任何限定。本申请对于终端设备从N个时域变换值中选择某一个值的具体实现方式不作限定。
还应理解，对于r的不同取值，n p,r的取值可以相同，也可以不同。本申请对此不作限定。例如，在一种实现方式中，对于r的任意取值，n p,r均为0。也就是说，将对应于第r个接收端口、第p个发射端口的N个时域变换值中的第0个值作为对应于第r个接收端口、第p个发射端口的加权系数。
关于n p,r的相关说明可以参考上文对n p的相关描述，为了简洁，这里不再重复。
事实上，与每个发射端口对应的加权系数的数目并不一定与接收端口数相同。如前所述，R≥1，与每个发射端口对应的加权系数可以为R’个，1≤R’≤R。也就是说，当R＞1时，与每个发射端口对应的加权系数可以为R个，也可以少于R个。
在有些实现方式中，终端设备可以仅对部分接收端口上接收到的预编码参考信号进行信道估计，以确定对应于该部分接收端口的加权系数。
比如，该终端设备配置有2个接收端口。该终端设备仅对其中一个接收端口上接收到的预编码参考信号进行信道估计。该终端设备基于在该接收端口上接收到的每个(例如第p个)发射端口的预编码参考信号，可以估计得到N个信道估计值，该N个信道估计值经时域变换后可以得到一个与第p个发射端口对应的加权系数。
协议可以预先定义一些规则，以便于终端设备决定基于哪个接收端口上接收到的预编码参考信号来确定上报的加权系数。或者，协议也可以预先定义终端设备或者，网络设备可以通过信令预先通知终端设备基于哪个接收端口上接收到的预编码参考信号来确定加权系数。又或者，终端设备可以自行决定基于哪个接收端口上接收到的预编码信号来确定加权系数。本申请对此不作限定。
在有些实现方式中，终端设备也可以基于多个接收端口上接收到的预编码参考信号进行信道估计所得的信道估计值进行加权，并将加权后的值进行时域变换；或者，也可以基于多个接收端口中每个接收端口上接收到的预编码参考信号分别进行信道估计所得的信道估计值进行时域变换得到的值加权求和，从而将对应于一个发射端口、多个接收端口的加权系数做了加权，所得到的与每个发射端口对应的加权系数的个数小于接收端口数R。
比如，该终端设备配置有4个接收端口。该终端设备可以基于每2个接收端口上接收到的预编码参考信号进行信道估计所得的信道估计值进行加权，并将加权后的值进行时域变换，由此可以得到对应于一个(例如第p个)发射端口的2个加权系数；或者，终端设备也可以基于4个接收端口中的每个接收端口上接收到的预编码参考信号进行信道估计 所得的信道估计值进行时域变换，以得到与4个接收端口分别对应的值，然后将每2个接收端口对应的值加权求和，从而可以得到对应于一个(例如第p个)发射端口的2个加权系数。
应理解，上文仅为便于理解，列举了一些接收端口与加权系数的对应关系，但这些示例仅为便于理解，不应对本申请构成任何限定。本申请对于接收端口与加权系数的对应关系不作限定。
还应理解，上文所述的对接收端口进行加权的方式仅为示例，并且本申请对各接收端口的权重也不做限定。
基于上文所述的方法，该终端设备可以确定与P个发射端口中的每个发射端口对应的一组加权系数。终端设备可以基于所确定的与每个发射端口对应的加权系数，生成第一指示信息。
该第一指示信息在用于指示对应于该P个发射端口的P组加权系数时，例如可以构造维度为P×R’的矩阵。为便于区分和说明，将由该P组加权系数构造的矩阵称为系数矩阵。该系数矩阵中的每一行可对应于一个发射端口。每一行所包括的加权系数的个数也就是对应于一个发射端口的加权系数的个数。可以理解，当R’＝R时，对应于每个发射端口的加权系数与R个接收端口对应。
下文示出了由对应于P个发射端口的P组加权系数构造的维度为P×R的系数矩阵的一例。
Figure PCTCN2019114491-appb-000062
该系数矩阵中的系数c p,r可以表示对应于第p个发射端口(或者说第p个角度时延对、对应于第k个角度向量和第l个时延向量)、第r个接收端口对应的加权系数。
终端设备对该P组加权系数的值例如可以通过量化值、量化值的索引或者其他形式来指示。在一种实现方式中，终端设备可以对该P组加权系数进行归一化处理，并基于归一化处理后的结果生成第一指示信息。所谓归一化处理，就是在归一化单位的范围内将所有加权系数的幅度值控制在不超过1的范围内的处理。
示例性地，终端设备可以从该P组加权系数中确定幅值最大的加权系数(为便于区分和说明，例如将该加权系数的幅值记作最大幅值)。该终端设备可以对除了该加权系数之外的其余加权系数的幅值分别除以该最大幅值，得到与各加权系数对应的比值。终端设备对该P组加权系数归一化后，上述最大幅值被归一化为1，其余加权系数分别为各自对应的比值。经归一化之后，终端设备可以基于各归一化之后的结果的量化值或非量化值生成第一指示信息。
应理解，上述归一化处理是在P个发射端口的范围内处理的，即，归一化单位为P个发射端口。但这仅为便于理解而示意。该归一化单位也可以是一个发射端口，即，对上述系数矩阵中的每一行分别进行归一化处理。本申请对于归一化单位不作限定。
还应理解，上述归一化处理的过程仅为示例，不应对本申请构成任何限定。由于归一化处理的具体实现方式为现有技术，为了简洁，这里不作详细说明。
如前所述，网络设备可以配置有J个极化方向，J≥1。该终端设备可以按照上文所述 的方法，基于每个极化方向上的发射端口的预编码参考信号进行信道估计，得到各极化方向上与每个发射端口对应的加权系数。
假设极化方向数J为2，则基于该2个极化方向上中每个极化方向的P个发射端口的预编码参考信号，可以确定P组加权系数。由对应于2个极化方向上的2P个发射端口的加权系数可以构造维度为2P×R(假设R’＝R)的系数矩阵如下：
Figure PCTCN2019114491-appb-000063
该系数矩阵中的前P行对应于第一极化方向上的P个发射端口。前P行中的加权系数是对应于第一极化方向上的P个发射端口对应的P组加权系数。该系数矩阵中的后P行对应于第二极化方向上的P个发射端口。后P行中的加权系数是对应于第二极化方向上的P个发射端口的P组加权系数。
应理解，上文仅为便于理解，以矩阵的形式示出了终端设备确定的与P个发射端口对应的加权系数。但这不应对本申请构成任何限定。终端设备在生成第一指示信息的过程中，并不一定会生成上述系数矩阵。
还应理解，终端设备在指示多个极化方向上的发射端口对应的加权系数时，例如可以按照预先约定的顺序依次指示。
例如，终端设备可以分别对第一极化方向上各发射端口对应的加权系数和第二极化方向上各发射端口对应的加权系数进行归一化处理，并基于归一化处理的结果生成第一指示信息。该第一指示信息可以包括用于指示该第一极化方向上各发射端口对应的加权系数的信息和用于指示第二极化方向上各发射端口对应的加权系数的信息。此情况下，归一化单位可以是一个极化方向上的P个发射端口。
又例如，终端设备也可以对两个极化方向上各发射端口对应的加权系数进行归一化处理，并基于归一化处理的结果生成第一指示信息。此情况下，归一化单位可以是两个极化方向上的2P个发射端口。
应理解，本申请对于终端设备指示加权系数的顺序不作限定。只要网络设备能够根据第一指示信息恢复出与J个极化方向上各发射端口对应的加权系数即可。
还应理解，终端设备在通过第一指示信息指示与各极化方向上各发射端口对应的加权系数时，并不一定表示该第一指示信息包括对全部的加权系数的指示。只要网络设备可以根据该第一指示信息确定出全部的加权系数，就可以认为该第一指示信息用于指示全部的加权系数。
例如，终端设备在通过第一指示信息指示对应于一个极化方向上的P个发射端口对应的加权系数时，比如上文所述的P×R’个加权系数，并不一定表示该第一指示信息包括该P×R’个加权系数中每个加权系数的指示。在对该P×R’个加权系数进行归一化处理之后， 终端设备可以指示最大幅值所对应的位置(比如所对应的发射端口和接收端口或者说在系数矩阵中的行和列)以及其他加权系数的幅值与最大幅值的比值等。也就是说，只要网络设备可以根据第一指示信息恢复出该P×R’个加权系数即可，便可以认为该第一指示信息用于指示该P×R’个加权系数。
此外，由于每个发射端口对应于一个角度向量和一个时延向量，或者说，对应于一个角度时延对，因此上述各加权系数均为对应于角度时延对的加权系数。网络设备可以根据各发射端口与角度向量和时延向量的对应关系，确定各加权系数所对应的角度时延对。
在步骤330中，终端设备发送该第一指示信息。相应地，在步骤330中，网络设备接收该第一指示信息。
具体地，该第一指示信息例如可以是CSI，也可以是CSI中的部分信元，还可以是其他信息。示例性地，该第一指示信息为预编码矩阵指示(precoding matrix indicator，PMI)。本申请对此不作限定。该第一指示信息可以携带在现有技术中的一个或者多个消息中由终端设备发送给网络设备，也可以携带在新设计的一个或者多个消息中由终端设备发送给网络设备。终端设备例如可以通过物理上行资源，如物理上行共享信道(physical uplink share channel，PUSCH)或物理上行控制信道(physical uplink control channel，PUCCH)，向网络设备发送该第一指示信息，以便于网络设备基于该第一指示信息确定预编码矩阵。
终端设备通过物理上行资源向网络设备发送第一指示信息的具体方法可以与现有技术相同，为了简洁，这里省略对其具体过程的详细说明。
在上述实现方式中，由于终端设备基于接收端口反馈对应于P个发射端口的P组加权系数，每组加权系数可以包括对应于一个或多个加权系数，每个加权系数可以对应于一个或多个接收端口。
可选地，该方法还包括：终端设备发送第五指示信息，该第五指示信息用于指示接收端口数R。相应地，网络设备接收该第五指示信息。
通过向网络设备指示接收端口数，以便网络设备根据接收端口数，确定第一指示信息所指示的加权系数的个数。
该第五指示信息和上述第一指示信息可以携带在同一信令中，也可以携带在不同的信令中，本申请对此不作限定。
应理解，终端设备基于接收端口反馈对应于P个发射端口的P组加权系数仅为一种可能的实现方式。不应对本申请构成任何限定。
在另一种实现方式中，该终端设备也可以基于传输层反馈对应于P个发射端口的P组加权系数。在这种实现方式中，上述第一指示信息所指示的对应于P个发射端口的P组加权系数中，每组加权系数可以包括与Z个传输层对应的Z个加权系数。
为便于理解，这里以对应于两个极化方向上的各发射端口的加权系数为例来说明终端设备确定基于传输层反馈的加权系数的过程。
假设终端设备确定的对应于每个发射端口的一组加权系数为R个，与R个接收端口对应。则该终端设备基于接收端口确定的加权系数可以通过矩阵表示为：
Figure PCTCN2019114491-appb-000064
终端设备可以对该系数矩阵进行SVD以得到基于传输层反馈的加权系数。终端设备基于传输层确定的加权系数可以通过矩阵表示为：
Figure PCTCN2019114491-appb-000065
该系数矩阵中的各加权系数以d表示，以与基于接收端口反馈的加权系数c区分。该系数矩阵中的前P行可以对应于第一极化方向，后P行可以对应于第二极化方向。Z个列对应于Z个传输层。因此该系数矩阵中的每一行可以表示对应于一个极化方向上的一个发射端口的一组加权系数。每组加权系数可以包括Z个加权系数，与Z个传输层对应。其中，前P行中的第p行、第z列的加权系数表示对应于第一极化方向上的第p个发射端口、第z个传输层的加权系数；后P行中的第p行、第z列的加权系数表示对应于第二极化方向上的第p个发射端口、第z个传输层的加权系数。
可以看到，终端设备基于接收端口而确定的对应于P个发射端口的P组加权系数，可以确定基于传输层反馈的对应于P个发射端口的P组加权系数。在上文中已经说明，基于接收端口确定的对应于P个发射端口的P组加权系数是基于上文所述的时域变换的方式获得的。因此在本申请实施例中，不管是基于接收端口反馈P组加权系数，还是基于传输层反馈P组加权系数。终端设备对每个加权系数的确定都可以通过上文所述的时域变换的方式来获得。
终端设备可以基于上述对应于各极化方向上的P个发射端口的P组加权系数，生成第一指示信息，以通过该第一指示信息指示对应于各极化方向上的P个发射端口的P组加权系数。终端设备通过第一指示信息指示基于传输层反馈的加权系数的具体方法与上文所述通过第一指示信息指示基于接收端口反馈的对应于P个发射端口的P组加权系数的具体方法相似，例如可以对加权系数进行归一化处理等。由于上文已经详细描述了终端设备通过第一指示信息指示基于接收端口反馈的加权系数的具体过程，为了简洁，这里不再赘述。
应理解，上文示例的终端设备确定基于传输层反馈的加权系数的过程仅为示例，不应对本申请构成任何限定。本申请对于终端设备确定基于传输层反馈的加权系数的具体方法 不作限定。
可选地，该方法还包括：终端设备发送第六指示信息，该第六指示信息用于指示传输层数Z。相对应地，网络设备接收该第六指示信息。
该第六指示信息例如可以与上述第一指示信息携带在同一信令中，也可以携带在不同的信令中。示例性地，该第五指示信息为秩指示(rank indication，RI)。应理解，本申请对于用于携带第六指示信息的具体信令不作限定。
在步骤340中，网络设备根据第一指示信息确定预编码矩阵。
如前所述，终端设备可以基于接收端口反馈对应于P个发射端口的P组加权系数，也可以基于传输层反馈对应于P个发射端口的P组加权系数。网络设备可以基于不同的反馈粒度，根据第一指示信息确定预编码矩阵。
下面分别对上述两种情况下网络设备根据第一指示信息确定预编码矩阵的具体过程做详细说明。
若终端设备基于接收端口反馈对应于P个发射端口的P组加权系数，则该第一指示信息所指示的加权系数可以包括一个或多个接收端口对应的加权系数。网络设备可以基于第一指示信息所指示的加权系数，以及每个加权系数所对应的角度时延对，重构下行信道，进而确定各频域单元的预编码矩阵。
为便于理解，这里假设终端设备反馈的P组加权系数中的每组加权系数包括与R个接收端口对应的R个加权系数。则，每个接收端口所对应的P个加权系数可以分别与P个角度时延对一一对应。网络设备可以基于与终端设备的每个接收端口对应的P个加权系数，以及P个角度时延对中每个角度时延对中包含的角度向量和时延向量，构造与各接收端口对应的空频矩阵。为便于区分和说明，在本申请实施例中，将与接收端口对应的空频矩阵记为H DL,R。
Figure PCTCN2019114491-appb-000066
表示与第r个接收端口对应的空频矩阵，r可以取0至R-1中的任意整数值。
在本实施例中，与第r个接收端口对应的空频矩阵可以通过P个角度时延对和与第r个接收端口对应的P个加权系数确定。其中，P个角度时延对可用于构造P个空频分量矩阵。如前所述，由K个角度向量中的第k个角度向量a(θ k)和L个时延向量中的第l个时延向量b(τ l)可以构造空频分量矩阵a(θ k)×b(τ l) H。与第r个接收端口对应的空频矩阵
Figure PCTCN2019114491-appb-000067
可以是P个空频分量矩阵的加权和。即，
Figure PCTCN2019114491-appb-000068
表示基于第r个接收端口反馈的与第k个角度向量和第l个时延向量对应的加权系数。该空频矩阵的维度可以是T×N。
上文示出的空频矩阵
Figure PCTCN2019114491-appb-000069
的计算式假设K个角度向量与L个时延向量是相互共用的。当至少两个角度向量对应的时延向量不同时，上式可以变形为：
Figure PCTCN2019114491-appb-000070
或者，当至少两个时延向量对应的角度向量不同时，上式可以变形为
Figure PCTCN2019114491-appb-000071
下文中为方便说明，均以
Figure PCTCN2019114491-appb-000072
为例来说明。可以理解，无论各角度向量对应的时延向量是否相同，或各时延向量对应的角度向量是否相同，对于预编 码矩阵的确定方法没有影响。
需要说明的是，上文为方便理解，以发射天线的一个极化方向为例来说明了确定与接收端口对应的空频矩阵的具体过程。但这不应对本申请构成任何限定。当发射天线的极化方向数大于1时，网络设备仍然可以基于如上所述的方法来确定与各接收端口对应的空频矩阵。
例如，极化方向数为2，与第r个接收端口对应的空频矩阵可以通过如下计算式确定：
Figure PCTCN2019114491-appb-000073
其中，
Figure PCTCN2019114491-appb-000074
表示基于第r个接收端口反馈的第一极化方向上与第k个角度向量和第l个时延向量对应的加权系数；
Figure PCTCN2019114491-appb-000075
表示基于第r个接收端口反馈的第二极化方向上与第k个角度向量和第l个时延向量对应的加权系数。
应理解，上文对于2个极化方向定义的空频矩阵
Figure PCTCN2019114491-appb-000076
的计算式仅为示例，不应对本申请构成任何限定。例如，在不同的极化方向上加载的时延向量和/或角度向量的数量可以相同也可以不同，在不同的极化方向上加载的时延向量和/或角度向量可以相同，也可以不同。
对于R个接收端口而言，网络设备可以分别基于每个接收端口对应的P个加权系数确定空频矩阵
Figure PCTCN2019114491-appb-000077
至
Figure PCTCN2019114491-appb-000078
由此，网络设备可确定与各频域单元对应的下行信道矩阵。
以RB作为频域单元的一例。对于N个RB中的第n个RB，网络设备可以确定与第n个RB对应的下行信道矩阵的共轭转置(V (n)) H。其中，矩阵(V (n)) H可以是由上述基于R个接收端口分别确定的R个空频矩阵
Figure PCTCN2019114491-appb-000079
至
Figure PCTCN2019114491-appb-000080
中每个空频矩阵中的第n个列向量确定。例如，将
Figure PCTCN2019114491-appb-000081
中的第n列作为矩阵(V (n)) H的第0列，将
Figure PCTCN2019114491-appb-000082
中的第n列作为矩阵(V (n)) H的第1列；以此类推，可以将
Figure PCTCN2019114491-appb-000083
中的第n列作为矩阵(V (n)) H的第R-1列。由此可以得到矩阵(V (n)) H，进而可以确定与第n个RB对应的下行信道矩阵V (n)。
基于上述方法可以确定与各RB分别对应的下行信道矩阵。
网络设备可以进一步根据各RB的下行信道矩阵确定各RB的预编码矩阵。例如，网络设备可以通过对下行信道矩阵或信道矩阵的协方差矩阵进行SVD的方式确定预编码矩阵，或者，也可以通过对下行信道矩阵的协方差矩阵进行特征值分解(eigenvalue decomposition，EVD)的方式确定。
应理解，网络设备根据信道矩阵确定预编码矩阵的具体方式可以参考现有技术，本申请对于预编码矩阵的确定方式不作限定。
还应理解，上文中仅为便于理解，示出了网络设备基于空频矩阵确定下行信道矩阵，进而确定预编码矩阵的具体过程。但这不应对本申请构成任何限定。网络设备也可以根据空频矩阵直接确定预编码矩阵。
需要说明的是，上文仅为便于理解示出了终端设备基于P组加权系数中的每个加权系数对应于一个接收端口的情况。如前所述，终端设备在基于接收端口反馈加权系数时，每组加权系数的个数并不一定等于接收端口数。比如，接收端口数大于1，但终端设备仅基 于其中某一个接收端口上接收到的预编码参考信号进行信道估计和反馈。每组加权系数可以仅包括一个加权系数。此情况下，网络设备可以将基于该接收端口反馈的加权系数当成每个接收端口的加权系数，进而按照上文所述的方法确定预编码矩阵。又比如，接收端口数大于1，终端设备将多个接收端口的信道估计值加权后进行时域变换并反馈。每组加权系数包括的加权系数的个数小于接收端口数。此情况下，网络设备可以将基于该多个接收端口反馈的加权系数当成该多个接收端口的加权系数，进而按照上文所述的方法确定预编码矩阵。本申请对于网络设备基于接收到的加权系数确定预编码矩阵的具体方式不作限定。
若终端设备基于传输层反馈对应于P个发射端口的P组加权系数，则该第一指示信息所指示的加权系数可以包括一个或多个传输层的加权系数。网络设备可以基于每个传输层对应的加权系数，以及每个加权系数所对应的角度时延对，确定与传输层对应的空频矩阵，进而确定各频域单元的预编码矩阵。
具体地，由于每个传输层对应的P个加权系数可以分别与P个角度时延对一一对应。网络设备可以基于每个传输层对应的P个加权系数，以及P个角度时延对中每个角度时延对中包含的角度向量和时延向量，构造与传输层对应的空频矩阵。为便于区分和说明，在本申请实施例中，将与接收端口对应的空频矩阵记为H DL,Z。
Figure PCTCN2019114491-appb-000084
表示与第z个传输层对应的空频矩阵，z可以取0至Z-1中的任意整数值。
在本实施例中，与第z个传输层对应的空频矩阵
Figure PCTCN2019114491-appb-000085
可以通过P个角度时延对和与第z个传输层对应的P个加权系数确定。其中，P个角度时延对可用于构造P个空频分量矩阵。与第z个传输层对应的预编码向量可以是P个空频分量矩阵的加权和。即，
Figure PCTCN2019114491-appb-000086
表示基于第r个接收端口反馈的与第k个角度向量和第l个时延向量对应的加权系数。该空频矩阵的维度可以是T×N。
上文示出的空频矩阵
Figure PCTCN2019114491-appb-000087
的计算式假设K个角度向量与L个时延向量是相互共用的。当至少两个角度向量对应的时延向量不同时，上式可以变形为：
Figure PCTCN2019114491-appb-000088
或者，当至少两个时延向量对应的角度向量不同时，上式可以变形为
Figure PCTCN2019114491-appb-000089
下文中为方便说明，均以
Figure PCTCN2019114491-appb-000090
为例来说明。可以理解，无论各角度向量对应的时延向量是否相同，或各时延向量对应的角度向量是否相同，对于预编码矩阵的确定没有影响。
需要说明的是，上文为方便理解，以发射天线的一个极化方向为例来说明了确定与接收端口对应的空频矩阵的具体过程。但这不应对本申请构成任何限定。当发射天线的极化方向数大于1时，网络设备仍然可以基于如上所述的方法来确定与各接收端口对应的空频矩阵。
例如，极化方向数为2，与第r个接收端口对应的空频矩阵可以通过如下计算式确定：
Figure PCTCN2019114491-appb-000091
其中，
Figure PCTCN2019114491-appb-000092
表示基于第z个传输层反馈的第一极化方向上与第k个角度向量和第l个时延向量对应的加权系数；
Figure PCTCN2019114491-appb-000093
表示基于第z个传输层反馈的第二极化方向上与第k个角度向量和第l个时延向量对应的加权系数。
应理解，上文对于2个极化方向定义的空频矩阵
Figure PCTCN2019114491-appb-000094
的计算式仅为示例，不应对本申请构成任何限定。例如，在不同的极化方向上加载的时延向量和/或角度向量的数量可以相同也可以不同，在不同的极化方向上加载的时延向量和/或角度向量可以相同，也可以不同。
对于Z个传输层而言，网络设备可以分别基于每个传输层对应的P个加权系数确定与各传输层对应的空频矩阵
Figure PCTCN2019114491-appb-000095
至
Figure PCTCN2019114491-appb-000096
由此，网络设备可确定与各RB对应的预编码矩阵W (n)。
以RB作为频域单元的一例。对于N个RB中的第n个RB，网络设备可以确定与第n个RB对应的下行信道矩阵的共轭转置(V (n)) H。其中，矩阵(V (n)) H可以是由上述基于R个接收端口分别确定的R个空频矩阵
Figure PCTCN2019114491-appb-000097
至
Figure PCTCN2019114491-appb-000098
中每个空频矩阵中的第n个列向量确定。
第n个RB对应的预编码矩阵W (n)可以是由上述基于Z个传输层分别确定的Z个空频矩阵
Figure PCTCN2019114491-appb-000099
至
Figure PCTCN2019114491-appb-000100
中每个空频矩阵中的第n个列向量构建。例如，将
Figure PCTCN2019114491-appb-000101
中的第n列作为下行信道矩阵W (n)的第0列，将
Figure PCTCN2019114491-appb-000102
中的第n列作为下行信道矩阵W (n)的第1列；以此类推，可以将
Figure PCTCN2019114491-appb-000103
中的第n列作为下行信道矩阵W (n)的第Z-1列。基于上述方法可以确定与各RB分别对应的预编码矩阵。
应理解，上文仅为便于理解，以空频分量矩阵为例详细说明了网络设备确定预编码矩阵的具体过程。但这不应对本申请构成任何限定。网络设备也可以基于P个角度时延对确定P个空频分量向量，进而确定预编码矩阵。本领域的技术人员基于P个角度时延对可以构造不同形式的P个空频基本单位，进而确定预编码矩阵。基于P个角度时延对而构造的不同形式的P个空频基本单位，进而基于P个空频基本单位的加权和来确定预编码矩阵的方式均应落入本申请要求的保护范围内。
还应理解，上文仅为示例，示出了网络设备根据第一指示信息确定预编码矩阵的可能实现方式，但这不应对本申请构成任何限定。本申请对于网络设备根据第一指示信息确定预编码矩阵的具体实现方式不作限定。本领域的技术人员基于相同的构思，对上文列举的矩阵运算进行变换或者等价的替换，确定预编码矩阵的方法均应落入本申请的保护范围内。
还应理解，上文中描述的与各频域单元对应的预编码矩阵的确定过程是以RB作为频域单元的一例来描述的。因此所确定的下行信道是与RB对应的下行信道，所确定的预编码矩阵是与RB对应的预编码矩阵。与RB对应的预编码矩阵可以是指，以RB为粒度基于该RB对应的信道矩阵确定的预编码矩阵，或者说，基于该RB上接收到的预编码参考信号确定的预编码矩阵，可用于对通过该RB传输的数据做预编码。与RB对应的下行信道，可以是指，基于该RB上接收到的预编码参考信号确定的下行信道，可用于确定与该 RB对应的预编码矩阵。
当频域单元的粒度较大，如频域单元为子带、PRG或者PRB时，网络设备可以根据每个频域单元中各RB对应的预编码矩阵确定与频域单元的预编码矩阵。
若每个频域单元包括一个用于承载参考信号的RB，则网络设备可以将该RB对应的预编码矩阵作为所属的频域单元对应的预编码矩阵。若每个频域单元包括多个用于承载参考信号的RB，则网络设备例如可以将同一个频域单元中与多个RB对应的预编码矩阵的相关矩阵求平均后进行SVD以确定该频域单元对应的预编码矩阵；网络设备又例如可以将同一个频域单元中与多个RB对应的预编码矩阵的平均作为该频域单元对应的预编码矩阵，等等。
应理解，网络设备根据频域单元中多个RB对应的预编码矩阵确定该频域单元的预编码矩阵的具体方法可以参考技术，而不限于上文所列举。本申请对于网络设备频域单元中多个RB对应的预编码矩阵确定该频域单元的预编码矩阵的具体方法不作限定。
还应理解，上文中在描述时提及的与某一角度向量和某一时延向量对应的加权系数，也就是，与某一角度向量和某一时延向量构成的角度时延对对应的加权系数。例如，与第k个角度向量和第l个时延向量对应的加权系数，也就是，与第k个角度向量和第l个时延向量构成的角度时延对对应的加权系数。为了简洁，这里不再一一举例说明。
在本申请实施例中，网络设备例如可以基于上行信道测量所确定的角度和时延，对下行参考信号进行预编码，使得终端设备根据预编码后的参考信号进行下行信道测量。由于网络设备基于上下行信道可互易的角度和时延对参考信号进行了预编码，使得终端设备检测到的下行信道的信息是不具有互易性的信息。因此，终端设备可以不必反馈空域和频域的向量(如上述角度向量和时延向量)，大大减小了终端设备的反馈开销。此外，通过将频域的信道转换到时域，将时域变换所得到的值作为加权系数来反馈，基于由多个不连续的等效信道进行频域累加求和得到的加权系数而恢复的信道不准确的问题可以得以避免，有利于提高系统传输性能。因此在减小反馈开销的同时，仍能保证较高的反馈精度。再者，通过对下行参考信号进行空域预编码，可以减小参考信号的端口数，从而可以降低导频开销。
应理解，本申请实施例中仅为便于理解，示出了空频矩阵由真实的信道的共轭转置得到的情况下，下行信道测量并确定预编码矩阵的具体过程。但这不应对本申请构成任何限定。真实的信道与空频矩阵H DL的关系并不是固定不变的。对空频矩阵以及空频分量矩阵的不同定义，可能会使得真实的信道与空频矩阵H DL之间的关系发生变化。例如，空频矩阵H DL可以由真实的信道的共轭转置得到，也可以由真实的信道的转置得到。
当对空频矩阵与信道矩阵间的关系的定义不同时，在加载时延和角度时网络设备所执行的操作也有所不同，终端设备在进行信道测量并反馈时所执行的操作也相应地发生变化。但这只是终端设备和网络设备的实现行为，不应对本申请构成任何限定。本申请对于信道矩阵的定义、空频矩阵的维度及其定义以及二者间的转换关系不作限定。同理，本申请对于空频矩阵与预编码矩阵间的转换关系也不作限定。
上文方法实施例中，以基于角度向量和时延向量对参考信号进行预编码为例，详细说明了本申请提供的信道测量方法。但这不应对本申请构成任何限定。网络设备也可以仅基于时延向量或角度向量对参考信号进行预编码，以便于终端设备基于预编码参考信号进行下行信道测量。下文实施例以仅基于时延向量对参考信号进行预编码为例，详细说明本申 请提供的信道测量方法。
图4是从设备交互的角度示出的本申请另一实施例提供的信道测量方法400的示意性流程图。图4示出的方法400可以包括步骤410至步骤440。下面详细说明方法400中的各步骤。
为了便于理解，下文中仍然以一个极化方向的发射天线发送的预编码参考信号，详细说明终端设备进行信道测量和反馈的过程。该一个极化方向的发射天线可以是网络设备所配置的J个极化方向的发射天线中任意一个极化方向的发射天线。本申请对于网络设备所配置的发射天线的极化方向数J不作限定。
在步骤410中，终端设备接收预编码参考信号。相对应地，网络设备发送预编码参考信号。
在本实施例中，网络设备可以基于L个时延向量对参考信号进行预编码，具体可以是指频域预编码。由于该参考信号未经过空域预编码，在基于时延向量对参考信号做预编码之前，该参考信号可以与T个发射天线端口对应。
基于L个时延向量对参考信号进行预编码，所得到的预编码参考信号可以对应L组端口。每组端口可以与基于同一个时延向量对T个发射天线端口的参考信号预编码得到的预编码参考信号对应。每组端口可以包括最多T个端口，该T个端口可以与上述T个发射天线端口对应。因此，每个端口的预编码参考信号可以对应于一个时延向量和一个发射天线端口。换句话说，每个端口可以是一个时延向量和一个发射天线端口的组合。
在一种可能的实现方式中，网络设备可以遍历L个时延向量，对每个发射天线端口上的参考信号进行预编码。由此可以得到T×L种不同的组合，或者说，T×L个天线时延对。由于未涉及用作空域预编码的角度向量，每种组合可对应一个时延向量。换句话说，通过将L个时延向量加载在不同发射天线端口的参考信号上，可以得到时延向量与不同发射天线端口的组合共T×L种。
在另一种可能的实现方式中，网络设备可以遍历L个时延向量，基于L个时延向量中的一个或多个时延向量，对承载于N个频域单元中的部分频域单元上的参考信号进行预编码，并通过T个发射天线端口发送预编码后的参考信号。基于不同的时延向量预编码所得到的预编码参考信号可以被映射至不同的频域单元上。每个频域单元上承载的预编码参考信号可以是基于L个时延向量中的部分时延向量预编码得到。在多个RB中，至少有两个频域单元承载的预编码参考信号是基于不同的时延向量预编码得到。换句话说，通过将L个时延向量加载在不同的频域单元上，并通过T个发射天线端口发送，可以得到时延向量与发射天线端口的不同组合共T×L’种，1≤L’＜L，L’为整数。
应理解，上文仅为便于理解，列举了发射天线端口与时延向量的对应关系，但这不应对本申请构成任何限定。本申请对于发射天线端口与时延向量的对应关系不作限定。
可以理解的是，若网络设备基于L个时延向量对参考信号进行预编码，所发射的预编码参考信号的端口数可以是T个发射天线端口和L个时延向量所确定的组合数。在本实施例中，为方便说明，将发射端口数记作L组，每组发射端口可包括一时延向量以及与该时延向量对应的一个或多个发射天线端口。下文中为便于理解和说明，假设每组发射端口包括T个发射端口。即，该L个时延向量对于每个发射天线端口来说是可共用的。
由于时延具有上下行信道互易性，上述L个时延向量均可以是基于上行信道测量确定。由于在上文方法300中已经详细说明了网络设备基于上行信道测量确定L个较强的时 延的具体方法，为了简洁，这里不再赘述。
应理解，基于上行信道测量确定L个时延向量并不是唯一的实现方式，该L个时延向量例如可以是预先定义，如协议定义；或者，也可以是基于此前的一次或多次下行信道测量而反馈的结果统计确定。本申请对此不作限定。
由于在FDD模式下，上下行信道的时延可互易，则可以将上行信道测量所得的L个时延向量加载至下行参考信号，以便终端设备基于接收到的预编码参考信号进行下行信道测量。
网络设备可以基于该L个时延向量对下行参考信号，如CSI-RS，进行预编码，以得到预编码参考信号。网络设备可以通过预先配置的参考信号资源传输该预编码参考信号。由于上文已经结合图2详细说明了基于时延向量对参考信号进行预编码的过程，并在方法300中详细说明了网络设备通过参考信号资源传输预编码参考信号时用于区分不同发射端口的方式，为了简洁，这里不再赘述。
在步骤420中，终端设备生成第七指示信息，该第七指示信息用于指示对应于P个角度时延对的P组加权系数。
终端设备可以基于接收到的预编码参考信号进行信道估计，并基于估计所得的信道信息生成第七指示信息。该第七指示信息可用于指示对应于P个角度时延对的P组加权系数。其中，每组加权系数可以包括一个或多个加权系数。
其中该P个角度时延对可以是由上述L个时延向量和K个角度向量组合得到的。该K个角度向量可以与上述L个时延向量组合得到P个角度时延对，该P个角度时延对的加权可用于构建预编码矩阵。该K个角度向量例如可以是网络设备预先通过信令通知终端设备，也可以由终端设备自行确定。
在一种实现方式中，网络设备可以预先通过信令将角度的相关信息指示给终端设备。网络设备对角度的相关信息的指示可以有多种可能的方式。例如，网络设备可以根据上行信道的测量结果，通过信令向终端设备指示与L个时延向量中每个时延向量对应的角度向量；又例如，网络设备可以通过信令指示与L个时延向量中每个时延向量对应的角度，以便终端设备自行确定与各时延向量对应的角度向量；还例如，网络设备可以通过信令指示与L个时延向量中每个时延向量对应的一个角度(为便于区分和说明，记作参考角度)以及其他角度与该参考角度的差值或比值等。为了简洁，这里不一一举例说明。
需要说明的是，若与L个时延向量中的任意两个时延向量对应的角度向量相同，则可以认为该L个时延向量对应了相同的K个角度向量，或者说，该K个角度向量对每个时延向量来说可以认为是共用的。
在另一种实现方式中，终端设备可以基于所接收到的其他下行参考信号(比如解调参考信号(demodulation reference signal，DMRS)等)进行信道测量，以得到下行信道较强的K个角度向量。
在又一种实现方式中，终端设备可以基于此前的一次或多次下行信道测量统计确定K个角度向量。
应理解，上文所列举的终端设备获取K个角度向量的具体方式仅为几种可能的实现方式，不应对本申请构成任何限定。本申请对于终端设备获取K个角度向量的具体方式不作限定。
在本申请实施例中，终端设备可以基于接收端口反馈对应于P个角度时延对的P组加 权系数。该第七指示信息所指示的对应于P个角度时延对的P组加权系数中，每组加权系数可以包括一个或多个加权系数。例如，每组加权系数可以包括R’个加权系数。1≤R’≤R，且R’为整数。上文方法300中已经对于R’的不同取值下P组加权系数中的每组加权系数与R个接收端口的关系做了详细说明，为了简洁，这里不再赘述。
下面首先说明终端设备基于接收端口确定加权系数时确定与P个角度时延对对应的P组加权系数的过程。
为便于理解，首先假设R＝1，即，每组加权系数可以包括一个加权系数。每组发射端口的预编码参考信号可以通过N个RB(即，频域单元的一例)来承载。此情况下，对应于每组发射端口的一组加权系数可以包括一个加权系数。该第七指示信息可用于指示对应于L组发射端口的L个加权系数。
由于终端设备能够识别的发射端口是预编码参考信号的端口，故终端设备可以基于每组发射端口来进行信道估计。
如前所述，在接收端口数为1的情况下，若网络设备基于角度向量和时延向量对参考信号进行预编码，则对应于每个发射端口的加权系数可以由N个RB的信道估计值累加求和得到。
终端设备在接收到来自网络设备的预编码参考信号之后，可以在各个RB上进行信道估计。并可根据预先确定的与各时延向量对应的角度向量，对估计所得的信道信息进行处理，以确定对应于每个角度时延对的一组加权系数。
如前所述，若网络设备基于L个时延向量对参考信号进行预编码，则终端设备所接收到的真实信道可以表示为F HH DL H，其维度可以是L×T。则系数矩阵C DL可以通过计算式C DL＝S H(F HH DL H) H确定。该系数矩阵C DL中的各元素可以分别由经过了频域预编码后的真实信道F HH DL H的共轭转置(F HH DL H) H左乘S H得到。
由矩阵乘法运算可以知道，将(F HH DL H) H左乘S H时，(F HH DL H) H中的每个列向量包括的元素数与S H中每个行向量包括的元素数相同。在本实施例中，(F HH DL H) H中的每个列向量包括的元素数与S H中每个行向量包括的元素数可以均为T。当行向量与列向量相乘时，需要将行向量中的各元素(如第t个元素，t在1至T中遍历取值)分别与列向量中的相应元素(如第t个元素，t在1至T中遍历取值)相乘后再求和。因此，终端设备在将角度向量加载到各个RB上的信道估计值之后，再对加载同一角度向量得到的N个RB上的信道估计值求和，便可以得到与一个角度向量和一个时延向量(即，一个角度时延对)对应的加权系数。
应理解，本文中示出的空频矩阵H DL与信道矩阵的关系仅为示例。不同的定义方式可能会造成二者间关系的变化。但无论怎样定义，都只是影响网络设备和终端设备的内部实现，因此都不应对本申请构成任何限定。本申请对于网络设备和终端设备的内部实现行为不作限定。
在本实施例中，若网络设备基于L个时延向量中的每个时延向量对同一RB上承载的参考信号进行预编码，该RB上承载的预编码参考信号可对应L×T个发射端口，或者说，L组发射端口。每组端口包括T个发射端口。每组发射端口对应于L个时延向量中的一个时延向量。
在一种实现方式中，终端设备可以基于在一个接收端口上接收到的每组发射端口的预 编码参考信号估计所得的信道信息来确定各角度时延对对应的加权系数。
终端设备可以根据N个RB中第n个RB上接收到的对应于同一组发射端口的预编码参考信号，确定第n个RB上与每组发射端口对应的信道信息。例如，基于第l组发射端口的预编码参考信号，估计所得的信道信息可以是维度为1×T的向量，例如记作
Figure PCTCN2019114491-appb-000104
假设K个角度向量是L个时延向量共用的角度向量，对于K个角度向量中的第k个角度向量a(θ k)，则第n个RB上，与第k个角度向量和第l个时延向量构成的角度时延对的信道信息例如可以表示为
Figure PCTCN2019114491-appb-000105
假设该K个角度向量中的一个或多个角度向量对应于L个时延向量中的一个时延向量，如，L个时延向量中的第l个时延向量对应于K个角度向量中的K l个角度向量，第l个时延向量对应的K个角度向量中的K l个角度向量。则，第n个RB上，与第l个时延向量与K l个角度向量中的第k l个角度向量构成的角度时延对的信道信息例如可以表示为
Figure PCTCN2019114491-appb-000106
基于同样的方法，终端设备可以确定N个RB中每个RB上对应于一个时延向量和一个角度向量的信道信息，或者说，每个RB上对应于一个角度时延对的信道信息。
应理解，上文列举的用于确定各角度时延对的加权系数的方法以及计算式仅为示例，不应对本申请构成任何限定。本申请对于确定各角度时延对的加权系数的具体方法不作限定。此外，由于对角度向量的定义不同，该计算式也可能发生变化。本申请对于各向量的具体形式不作限定，因此对于向量间的运算方式也不做限定。
如前所述，由于终端设备接收到的预编码参考信号是基于时域向量进行预编码后的参考信号，终端设备所接收到的等效信道在频域上并不连续。因此基于上述方法所确定的各RB上对应于同一角度时延对的信道信息并不准确，若直接将N个RB上对应于同一角度时延对的信道信息直接累加求和所得的结果并不准确。本实施例中仍然可以采用时域变换的方式来获取更为精确的加权系数。
终端设备可以将对应于同一角度时延对的N个RB上的信道信息进行时域变换，以获得变换后的N个值。该N个值中的第n p个值可以作为与第p个角度时延对对应的加权系数。
在一种实现方式中，终端设备可以通过时域滤波的方式来获得与每个角度时延对对应的加权系数。上文方法300中的步骤320中已经对时域滤波的具体过程做了详细说明，为了简洁，这里不再赘述。
基于上文所述的方法，终端设备可以确定与L个时延向量和K个角度向量所组合的P个角度时延对对应的P组加权系数。每组加权系数可以包括R’个加权系数，1≤R’≤R，R’为整数。每组内的加权系数可以与R个接收端口中的一个或多个对应。应理解，终端设备对R’个加权系数中每个加权系数的确定过程均可以参考上文所述的方法，为了简洁，这里不再赘述。
在另一种实现方式中，终端设备还可以基于传输层反馈与P个角度时延对对应的P组加权系数。终端设备根据基于接收天线确定的对应于P个发射端口的P组加权系数，确定基于传输层反馈的对应于P个发射端口的P组加权系数的具体实现过程可以参考上文方法300的步骤320中的相关说明。由于在上文方法300的步骤320中对该具体过程做了详细说明，为了简洁，这里不再赘述。
应理解，上文仅为便于理解，示出了基于一个极化方向的P个发射端口发送的预编码 参考信号进行信道测量和反馈的过程。但这不应对本申请构成任何限定。对于多个极化方向，终端设备可以基于上文所述相同的方法来确定各极化方向上对应于P个发射端口的P组加权系数。
还应理解，终端设备基于所确定的加权系数生成第七指示信息的具体过程可以参考上文方法300中步骤330中终端设备生成第一指示信息的具体过程。为了简洁，这里不再赘述。
在步骤430中，终端设备发送该第七指示信息。相应地，网络设备接收该第七指示信息。
在步骤440中，网络设备根据该第七指示信息确定预编码矩阵。
应理解，步骤430至步骤440的具体过程可以与上文方法300中步骤330至步骤340的具体过程相同。对步骤430至步骤440的相关描述可以参考上文方法300中步骤330至步骤340的相关描述，为了简洁，这里不再重复。
在本申请实施例中，网络设备基于上行信道测量所确定的角度和时延，对下行参考信号进行预编码，使得终端设备根据预编码后的参考信号进行下行信道测量。由于网络设备基于上下行信道可互易的时延对参考信号进行了预编码，使得终端设备检测到的下行信道的信息是不具有互易性的信息。因此，终端设备可以不必反馈空域和频域的向量(如上述角度向量和时延向量)，大大减小了终端设备的反馈开销。此外，通过将频域的信道转换到时域，将时域变换所得到的值作为加权系数来反馈，基于由多个不连续的等效信道进行累加求和得到的加权系数而恢复的信道不准确的问题可以得以避免，有利于提高传输性能。因此在减小反馈开销的同时，仍能保证较高的反馈精度。
应理解，上文仅为便于理解，示出了网络设备仅基于时延向量对参考信号进行预编码，终端设备基于预编码参考信号进行信道测量和反馈的一例。但这不应对本申请构成任何限定。网络设备也可以仅基于角度向量对参考信号进行预编码，终端设备也可以基于上文所述相似的方法，对基于预编码参考信号估计所得的信道信息进行时域变换，以获得对应于P个角度时延对的P组加权系数。由于其具体过程与上文所述相似，为了简洁，这里不做详细说明。
图5是从设备交互的角度示出的本申请实施例提供的信道测量方法500的示意性流程图。图5示出的方法500可以包括步骤510至步骤550。下面详细说明方法500中的各步骤。
在步骤510中，终端设备接收预编码参考信号。相对应地，网络设备发送预编码参考信号。
应理解，步骤510的具体过程可以与上文方法300中步骤310的具体过程相同。对步骤510的相关描述可以参考上文方法300中步骤310的相关描述，为了简洁，这里不再重复。
在步骤520中，终端设备生成第二指示信息，该第二指示信息用于指示对应于P个发射端口的P组加权系数。
终端设备可以基于接收到的预编码参考信号进行信道估计，并基于估计所得的信道信息生成第一指示信息。该第一指示信息可用于指示对应于P个发射端口的P组加权系数。其中，每组加权系数可以包括一个或多个加权系数。
在本申请实施例中，终端设备可以基于接收端口反馈对应于P个发射端口的P组加权 系数。该第一指示信息所指示的对应于P个发射端口的P组加权系数中，每组加权系数可以包括一个或多个加权系数。例如，每组加权系数可以包括R’个加权系数。1≤R’≤R，且R’为整数。上文方法300中已经对于R’的不同取值下P组加权系数中的每组加权系数与R个接收端口的关系做了详细说明，为了简洁，这里不再赘述。
如前所述，终端设备也可以基于传输层反馈对应于P个发射端口的P组加权系数。每组加权系数可以包括Z个加权系数，与Z个传输层对应。后文中会详细说明如何基于传输层确定P组加权系数的具体过程，这里暂且省略。
对于P个发射端口中的任意一个发射端口，如第p个发射端口，p可以在0至P-1中任意取整数值，终端设备可以通过执行以下流程来确定与第p个发射端口对应的加权系数。
在0至R-1范围内对r遍历取值，反复执行以下步骤i和步骤ii，以确定与第p个发射端口与第r个接收端口对应的加权系数：
步骤i、基于在第r个接收端口上接收到的第p个发射端口的预编码参考信号进行信道估计，得到分别对应于N个频域单元的信道信息。该N个频域单元可以分为一个或多个频域单元组，每个频域单元组包括N个频域单元中的一个或多个频域单元；
步骤ii、分别对步骤i中确定的、与一个或多个频域单元组中的频域单元对应的信道信息进行频域滤波，以得到滤波后的N个值；
步骤iii、对步骤ii中所确定的滤波后的N个值累加求和，所得的值即为与第p个发射端口和第r个接收端口对应的加权系数。
在0至P-1范围内对p遍历取值，反复执行以上流程，便可以得到对应于P个发射端口的P组加权系数。
下面详细说明终端设备基于接收端口反馈加权系数时，确定与P个发射端口对应的P组加权系数的过程。
为便于理解，首先假设R＝1，即，每组加权系数可以包括一个加权系数。每个发射端口的预编码参考信号可以通过N个RB(即，频域单元的一例)来承载。此情况下，对应于每个发射端口的一组加权系数可以包括一个加权系数。该第一指示信息可用于指示对应于P个发射端口的P个加权系数。
由于终端设备能够识别的发射端口是与预编码参考信号对应的端口，故终端设备可以基于接收到的每个发射端口的预编码参考信号来进行信道估计，以得到信道信息。可选地，该信道信息具体可以是基于接收到的预编码参考信号进行信道估计而得到的信道估计值。可以理解，该信道估计值具体可以是等效信道，即，加载了预编码的信道。
如前所述，P个发射端口可以与P个角度时延对具有一一对应关系。其中，该P个发射端口中的第p个发射端口所对应的预编码参考信号例如可以是基于上述K个角度向量中的第k个角度向量和L个时延向量中的第l个时延向量对参考信号进行预编码得到。因此，上文所述的与第p个发射端口对应的加权系数也就是第p个角度时延对的加权系数。
以下，不失一般性，详细说明终端设备确定与第p个发射端口对应的加权系数的过程。
对于该第p个发射端口的预编码参考信号，终端设备可以基于一个接收端口、N个RB上接收到的预编码参考信号进行信道估计得到的信道估计值确定第p个角度时延对的加权系数。该第p个角度时延对的加权系数可以由该N个RB上的N个信道估计值确定。假设终端设备基于第n个RB上接收到的第p个发射端口的预编码参考信号进行信道估计 所得到的信道估计值记为
Figure PCTCN2019114491-appb-000107
则终端设备基于第p个发射端口的预编码参考信号进行信道估计所得到的信道估计值可以记为：
Figure PCTCN2019114491-appb-000108
共N个信道估计值。可以看到，该N个信道估计值与N个RB对应，也就是与N个频域单元对应。
终端设备基于一个接收端口、N个RB上接收到的预编码参考信号进行信道估计以得到N个信道估计值的过程与上文方法300中步骤320所述的过程相同，具体过程可以参考上文方法300中步骤320中的相关描述，为了简洁，这里不再重复。
如前所述，对应于第p个发射端口的加权系数可以是N个RB上的信道估计值累加求和得到。然而，网络设备在基于时延向量对参考信号进行预编码时，是将时延向量中的N个元素分别加载在同一个发射端口所对应的N个RB上的。因此终端设备在每个RB上估计得到的信道估计值是不连续的。如果将该N个信道估计值直接累加求和的值作为第p个角度时延对的加权系数反馈，由此而恢复的下行信道可能也与真实的信道具有较大的差异，由此而确定的用于下行数传的预编码矩阵也就不能够与真实的信道很好地匹配，因此影响系统传输性能。
在本申请实施例中，终端设备可以在对该N个信道估计值进行累加求和之前，对该N个信道估计值进行滤波处理。示例性地，终端设备可以将该N个RB划分为一个或多个RB组，每个RB组可以包括多个RB，且各RB组中的RB互不重复。对每个RB组内的各RB对应的信道估计值进行滤波处理，得到滤波后的值。对滤波后的值(可以理解，滤波后的值仍为N个)累加求和，可以得到与第p个发射端口对应的加权系数。
举例而言，假设N＝20，每4个RB划分为一个RB组。例如，RB#0至RB#3作为一个RB组，RB#4至RB#7作为一个RB组，RB#8至RB#11为一个RB组，RB#12至RB#15作为一个RB组，RB#16至RB#19作为一个RB组。终端设备可以对该5个RB组分别进行滤波，得到滤波后的值。可以理解，滤波后的值仍为20个值。对滤波后的值累加求和，便可以得到与第p个发射端口对应的加权系数。
其中，被划分在一个RB组中进行滤波的一个或多个RB，可以称为绑定的RB(bundling RB，或RB Bundle)。
应理解，本申请对于每个RB组中包含的RB个数不做限定。同时，本申请对于划分RB组的具体规则不做限定。换句话说，本申请对于每个频域单元组中包含的频域单元个数不做限定。同时，本申请对于划分频域单元组的具体规则也不做限定。
可选地，终端设备基于维纳滤波系数对在每个RB组估计所得的信道估计值进行频域滤波。
由于网络设备基于时延向量对参考信号进行了预编码，本申请实施例对维纳滤波系数进行了修正。修正后的滤波系数W p可以表示为：
Figure PCTCN2019114491-appb-000109
其中，W p表示与第p个发射端口对应的滤波系数。
Figure PCTCN2019114491-appb-000110
表示修正后的相关矩阵，
Figure PCTCN2019114491-appb-000111
例如可以通过下式修正得到：
Figure PCTCN2019114491-appb-000112
其中，
Figure PCTCN2019114491-appb-000113
为相关矩阵，表示用于承载第p个发射端口的参考信号(可以理解，该参考信号是预编码参考信号)的一个RB组中各RB之间的相关性，或者，在导频密度大于1的情况下，也可以表示承载第p个发射端口的参考信号的一个RB组中的各参考信号RE之间的相关性。关于相关矩阵
Figure PCTCN2019114491-appb-000114
的相关描述可以参考现有技术中关于维纳滤波的相关技术，为了简洁，这里不作详细说明。
Figure PCTCN2019114491-appb-000115
为修正值。在本申请实施例中，该修正值可用于对
Figure PCTCN2019114491-appb-000116
进行修正。在本申请实施例中，该修正值可以是一个M×M维矩阵，M表示每个RB组中包含的RB个数。下文中为方便说明，令，
Figure PCTCN2019114491-appb-000117
SNR为信号噪声比，简称信噪比。I为单位阵。
在一种可能的设计中，上述一个或多个频域单元组中，任意两个频域单元组中包含的频域单元个数相同。例如，将频域单元分为t个频域单元组，每个频域单元组包括M个频域单元。则N＝t×M。
可以看到，用于对相关矩阵
Figure PCTCN2019114491-appb-000118
进行修正的修正值β p与时延相关。其中
Figure PCTCN2019114491-appb-000119
与第p个发射端口对应的第l个时延τ l相关。例如，可以是时延τ p，也可以是时延τ p的数学变换。本申请对此不作限定。如，
Figure PCTCN2019114491-appb-000120
或，
Figure PCTCN2019114491-appb-000121
等等。为了简洁，这里不一一举例说明。这里，将由时延τ p的数学变换得到的与时延τ p相关的参数称为时延τ p的相关参数。应理解，本申请对数学变换的具体方式不作限定。
由于该修正值与时延相关，因此终端设备在确定与第p个发射端口对应的加权系数时，需要预先获取
Figure PCTCN2019114491-appb-000122
或者说，时延τ l或时延τ l的相关参数。
在一种可能的实现方式中，网络设备可以预先通过信令向终端设备指示与每个发射端口对应的时延或时延的相关参数。
可选地，该方法500还包括：步骤530，网络设备发送第三指示信息，该第三指示信息用于指示与P个发射端口中的每个发射端口对应的时延或时延的相关参数。相应地，终端设备接收该第三指示信息。
其中，每个时延可以与网络设备对参考信号进行预编码时所使用的时延向量对应。
可选地，网络设备对时延的指示例如可以是时延，也可以是所对应的时延向量的索引。比如，网络设备对时延τ l的指示例如可以是τ l，也可以是τ l所对应的时延向量b(τ l)的索引。
可选地，网络设备对时延的相关参数的指示可以是：所述P个端口中的第一发射端口对应的时延τ 0，以及所述P个发射端口中除所述第一发射端口之外的其余端口对应的时延与所述第一发射端口对应的时延的差值Δτ。
其中第一发射端口例如可以是协议预定义的某一发射端口。例如，第一发射端口可以是P个发射端口中的第0个发射端口，或者，P个发射端口中的第P-1个发射端口，或者，任意指定的发射端口τ 0。以第一发射端口为P个发射端口中的第0个发射端口为例，其对应的时延例如记为。终端设备对时延的相关参数的指示例如可以是第1个发射端口至第P-1个发射端口中的每个发射端口对应的时延与第0个发射端口对应的时延τ 0的差值。
当然，通过指示差值的方式来指示各发射端口对应的时延仅为一种可能的实现方式，例如，还可以通过指示第一发射端口对应的时延τ 0，以及P个发射端口中除第一发射端口之外的其余发射端口对应的时延与第一发射端口对应的时延τ 0的比值的方式来指示各发射端口对应的时延。本申请对于指示时延的相关参数的具体方式不做限定。
需要说明的是，上文仅为便于理解，示出了各频域单元组包含相关个数的频域单元的情况。事实上，本申请对于各频域单元组包含的频域单元个数不做限定。各频域单元组包含的频域单元个数可以相同，也可以不同。在各频域单元组包含的频域单元个数不同的情况下，上述修正值β p可以是维度为M max×M max的矩阵。其中，M max表示各频域单元组中包含的频域单元个数的最大。即，每个频域单元组中包含的频域单元个数小于或等于M max。也就是说，修正值β p的维度可以是各频域单元组中包含的频域单元个数的最大值M max。可以理解，若将上述N个频域单元作为一个频域单元组，则M max＝N。
应理解，采用维纳滤波对各频域单元上的信道估计值进行滤波处理仅为一种可能的实现方式，不应对本申请构成任何限定。终端设备也可以采用其他可能的滤波方式对信道估计值进行滤波处理，例如，基于其他准则(如非MMSE)构建的滤波，一阶或高阶插值，卡尔曼滤波等。为了简洁，这里不一一列举。
基于上述频域滤波处理，终端设备可以获得与P个发射端口对应的P组加权系数。每组加权系数可以包括一个加权系数。
应理解，上文仅为便于理解，以R＝1为例详细说明了终端设备通过频域滤波处理，获得与每个发射端口对应的加权系数。但这不应对本申请构成任何限定。如前所述，在本申请实施例中，R≥1，与每个发射端口对应的加权系数可以包括R’个加权系数，其中R≥R’≥1。
对于R’的不同取值，上文方法300中的步骤320中已经详细说明了终端设备确定与每个发射端口对应的R’个加权系数的具体过程。本实施例中，终端设备确定与每个发射端口对应的R’个加权系数的具体过程与上文方法300中终端设备确定与每个发射端口对应的R’个加权系数的具体过程相似。所不同的是，方法300中基于时域变换的方式确定与每个发射端口对应的加权系数，本实施例中基于频域滤波的方式确定与每个发射端口对应的加权系数。除此之外，对R’的不同取值，终端设备所做的处理是相同的。为了简洁，这里不对R’的不同取值的情况做详细说明。
此外，如前所述，终端设备还可以基于传输层反馈对应于P个发射端口的P组加权系数。终端设备可以根据基于接收天线确定的对应于P个发射端口的P组加权系数，确定基于传输层反馈的对应于P个发射端口的P组加权系数。其具体实现过程可以参考上文方法300的步骤320中的相关说明。由于在上文方法300的步骤320中对该具体过程做了详细说明，为了简洁，这里不再赘述。
应理解，上文仅为便于理解，示出了基于一个极化方向的P个发射端口发送的预编码参考信号进行信道测量和反馈的过程。但这不应对本申请构成任何限定。对于多个极化方向，终端设备可以基于上文所述相同的方法来确定各极化方向上对应于P个发射端口的P组加权系数。
还应理解，终端设备基于所确定的加权系数生成第二指示信息的具体过程可以参考上文方法300中步骤330中终端设备生成第一指示信息的具体过程。为了简洁，这里不再赘述。
在步骤540中，终端设备发送该第二指示信息。相应地，在步骤530中，网络设备接收该第二指示信息。
在步骤550中，网络设备根据第二指示信息确定预编码矩阵。
应理解，步骤540至步骤550的具体过程可以与上文方法300中步骤330至步骤340的具体过程相同。对步骤540至步骤550的相关描述可以参考上文方法300中步骤330至步骤340的相关描述，为了简洁，这里不再重复。
在本申请实施例中，网络设备例如基于上行信道测量所确定的角度和时延，对下行参考信号进行预编码，使得终端设备根据预编码后的参考信号进行下行信道测量。由于网络设备基于上下行信道可互易的角度和时延对参考信号进行了预编码，使得终端设备检测到的下行信道的信息是不具有互易性的信息。因此，终端设备可以不必反馈空域和频域的相关信息(如上述角度向量和时延向量)，大大减小了终端设备的反馈开销。此外，通过基于每个发射端口对应的时延所确定的滤波系数对多个频域单元上估计所得到的信道信息进行滤波处理，可以降低噪声，且充分利用多个频域单元上导频间的相关性进一步使得滤波所得的与各个频域单元对应的信道信息更为准确。此外，通过滤波系数的补偿，使得原本不连续的等效信道可以进行更大程度的联合滤波，缓解了当前技术中因无法频域绑定而造成的信道估计不准确问题，进而提高传输性能。因此在减小反馈开销的同时，仍能保证较高的反馈精度，从而有利于提高系统的传输性能。再者，通过对下行参考信号进行空域预编码，可以减小参考信号的端口数，从而可以降低导频开销。
上文实施例以基于角度向量和时延向量对参考信号进行预编码为例，详细说明了本申请提供的信道测量方法。但这不应对本申请构成任何限定。网络设备也可以仅基于时延向量或角度向量对参考信号进行预编码，以便于终端设备基于预编码参考信号进行下行信道测量。下文实施例以仅基于时延向量对参考信号进行预编码为例，详细说明本申请提供的信道测量方法。
图6是从设备交互的角度示出的本申请又一实施例提供的信道测量方法600的示意性流程图。图6示出的方法600可以包括步骤610至步骤650。下面详细说明方法600中的各步骤。
为了便于理解，下文中仍然以一个极化方向的发射天线发送的预编码参考信号，详细说明终端设备进行信道测量和反馈的过程。该一个极化方向的发射天线可以是网络设备所 配置的J个极化方向的发射天线中任意一个极化方向的发射天线。本申请对于网络设备所配置的发射天线的极化方向数J不作限定。
在步骤610中，终端设备接收预编码参考信号。相对应地，网络设备发送预编码参考信号。
在本实施例中，网络设备可以基于L个时延向量对参考信号进行预编码，具体可以是指频域预编码。上文方法400中的步骤410中详细说明了网络设备基于L个时延向量对参考信号进行预编码的具体过程以及发射端口数与L的关系。本实施例中步骤610的具体过程可以参考上文方法400中步骤410中的相关描述，为了简洁，这里不再重复。
在步骤620中，终端设备生成第八指示信息，该第八指示信息用于指示对应于P个角度时延对的P组加权系数。
首先，终端设备可以基于在每个RB上接收到的每个发射端口的预编码参考信号进行信道估计，以得到N个RB上对应于每个发射端口的信道信息。终端设备基于预先获取的与各时延向量对应的角度向量对各信道估计值进行处理，以得到N个RB上对应于每个角度时延对的信道信息。
此后，终端设备可以基于上文所述的频域滤波的方法，对对应于同一角度时延对的N个信道信息进行频域滤波。例如，将N个RB分为一个或多个RB组，每个RB组可以包括一个或多个RB。终端设备可以对应于一个角度时延对的一个RB组为单位进行频域滤波。终端设备进行频域滤波的具体过程可以参考上文方法500中步骤520中的相关描述。为了简洁，这里不再赘述。
由于用作频域滤波的滤波系数与时延相关，因此终端设备在执行步骤620之前，还可以预先获取L个时延或时延的相关参数。
在一种可能的实现方式中，网络设备可以预先通过信令向终端设备指示与每个发射端口对应的时延或时延的相关参数。
可选地，该方法600还包括：步骤630，网络设备发送第九指示信息，该第九指示信息用于指示L个时延或时延的相关参数。相应地，终端设备接收该第九指示信息。
其中，每个时延可以与网络设备对参考信号进行预编码时所使用的时延向量对应。
网络设备通过信令指示L个时延或时延的相关参数的具体方式在上文方法500的步骤530中已经做了详细说明，为了简洁，这里不再赘述。
此外，如前所述，终端设备还可以基于传输层反馈对应于P个发射端口的P组加权系数。终端设备可以根据基于接收天线确定的对应于P个发射端口的P组加权系数，确定基于传输层反馈的对应于P个发射端口的P组加权系数。其具体实现过程可以参考上文方法300的步骤320中的相关说明。由于在上文方法300的步骤320中对该具体过程做了详细说明，为了简洁，这里不再赘述。
应理解，上文仅为便于理解，示出了基于一个极化方向的P个发射端口发送的预编码参考信号进行信道测量和反馈的过程。但这不应对本申请构成任何限定。对于多个极化方向，终端设备可以基于上文所述相同的方法来确定各极化方向上对应于P个发射端口的P组加权系数。
还应理解，终端设备基于所确定的加权系数生成第八指示信息的具体过程可以参考上文方法300中步骤330中终端设备生成第一指示信息的具体过程。为了简洁，这里不再赘述。
在步骤640中，终端设备发送该第八指示信息。相应地，网络设备接收该第八指示信息。
在步骤650中，网络设备根据第八指示信息确定预编码矩阵。
应理解，步骤640至步骤650的具体过程可以与上文方法300中步骤330至步骤340的具体过程相同。对步骤640至步骤650的相关描述可以参考上文方法300中步骤330至步骤340的相关描述，为了简洁，这里不再重复。
在本申请实施例中，网络设备基于上行信道测量所确定的时延，对下行参考信号进行预编码，使得终端设备根据预编码后的参考信号进行下行信道测量。由于网络设备基于上下行信道可互易的时延对参考信号进行了预编码，使得终端设备可以不必反馈频域的相关信息(如上述时延向量)，大大减小了终端设备的反馈开销。此外，通过基于每个发射端口对应的时延所确定的滤波系数对多个频域单元上估计所得到的信道信息进行滤波处理，可以降低噪声，且充分利用多个频域单元上导频间的相关性进一步使得滤波所得的与各个频域单元对应的信道信息更为准确。此外，通过滤波系数的补偿，使得原本不连续的等效信道可以进行更大程度的联合滤波，缓解了当前技术中因无法频域绑定而造成的信道估计不准确问题，进而提高传输性能。因此在减小反馈开销的同时，仍能保证较高的反馈精度，从而有利于提高系统的传输性能。
应理解，上文仅为便于理解，示出了网络设备仅基于时延向量对参考信号进行预编码，终端设备基于预编码参考信号进行信道测量和反馈的一例。但这不应对本申请构成任何限定。网络设备也可以仅基于角度向量对参考信号进行预编码，终端设备也可以基于上文所述相似的方法，对基于预编码参考信号估计所得的信道信息进行频域滤波，以获得对应于P个角度时延对的P组加权系数。由于其具体过程与上文所述相似，为了简洁，这里不做详细说明。
还应理解，在上文各实施例中，终端设备和/或网络设备可以执行各实施例中的部分或全部步骤。这些步骤或操作仅是示例，本申请实施例还可以执行其它操作或者各种操作的变形。此外，各个步骤可以按照各实施例呈现的不同的顺序来执行，并且有可能并非要执行本申请实施例中的全部操作。且，各步骤的序号的大小并不意味着执行顺序的先后，各过程的执行顺序应以其功能和内在逻辑确定，而不应对本申请实施例的实施过程构成任何限定。
图7是本申请实施例提供的通信装置的示意性框图。如图7所示，该通信装置1000可以包括处理单元1100和收发单元1200。
在一种可能的设计中，该通信装置1000可对应于上文方法实施例中的终端设备，例如，可以为终端设备，或者配置于终端设备中的部件(如芯片或芯片系统等)。
应理解，该通信装置1000可对应于根据本申请实施例的方法300至方法600中的终端设备，该通信装置1000可以包括用于执行图3中的方法300至图6中的方法600中终端设备执行的方法的单元。并且，该通信装置1000中的各单元和上述其他操作和/或功能分别为了实现图3中的方法300至图6中的方法600中任一方法的相应流程。
其中，当该通信装置1000用于执行图3中的方法300时，处理单元1100可用于执行方法300中的步骤320，收发单元1200可用于执行方法300中的步骤310和步骤330。应理解，各单元执行上述相应步骤的具体过程在上述方法实施例中已经详细说明，为了简洁，在此不再赘述。
当该通信装置1000用于执行图4中的方法400时，处理单元1100可用于执行方法400中的步骤420，收发单元1200可用于执行方法400中的步骤410和步骤430。应理解，各单元执行上述相应步骤的具体过程在上述方法实施例中已经详细说明，为了简洁，在此不再赘述。
当该通信装置1000用于执行图5中的方法500时，处理单元1100可用于执行方法500中的步骤520，收发单元1200可用于执行方法500中的步骤510、步骤530和步骤540。应理解，各单元执行上述相应步骤的具体过程在上述方法实施例中已经详细说明，为了简洁，在此不再赘述。
当该通信装置1000用于执行图6中的方法600时，处理单元1100可用于执行方法600中的步骤620，收发单元1200可用于执行方法600中的步骤610、步骤630和步骤640。应理解，各单元执行上述相应步骤的具体过程在上述方法实施例中已经详细说明，为了简洁，在此不再赘述。
还应理解，该通信装置1000为终端设备时，该通信装置1000中的收发单元1200可以通过收发器实现，例如可对应于图8中示出的终端设备2000中的收发器2020，该通信装置1000中的处理单元1100可通过至少一个处理器实现，例如可对应于图8中示出的终端设备2000中的处理器2010。
还应理解，该通信装置1000为配置于终端设备中的芯片时，该通信装置1000中的收发单元1200可以通过输入/输出接口实现，该通信装置1000中的处理单元1100可以通过该芯片或芯片系统上集成的处理器、微处理器或集成电路等实现。
在另一种可能的设计中，该通信装置1000可对应于上文方法实施例中的网络设备，例如，可以为网络设备，或者配置于网络设备中的部件(如芯片或芯片系统等)。
应理解，该通信装置1000可对应于根据本申请实施例的方法300至方法600中的网络设备，该通信装置1000可以包括用于执行图3中的方法300至图6中的方法600中网络设备执行的方法的单元。并且，该通信装置1000中的各单元和上述其他操作和/或功能分别为了实现图3中的方法300至图6中的方法600中任一方法的相应流程。
其中，当该通信装置1000用于执行图3中的方法300时，处理单元1100可用于执行方法300中的步骤340，收发单元1200可用于执行方法300中的步骤310和步骤330。应理解，各单元执行上述相应步骤的具体过程在上述方法实施例中已经详细说明，为了简洁，在此不再赘述。
当该通信装置1000用于执行图4中的方法400时，处理单元1100可用于执行方法400中的步骤440，收发单元1200可用于执行方法400中的步骤410和步骤430。应理解，各单元执行上述相应步骤的具体过程在上述方法实施例中已经详细说明，为了简洁，在此不再赘述。
当该通信装置1000用于执行图5中的方法500时，处理单元1100可用于执行方法500中的步骤550，收发单元1200可用于执行方法500中的步骤步骤510、步骤530和步骤540。应理解，各单元执行上述相应步骤的具体过程在上述方法实施例中已经详细说明，为了简洁，在此不再赘述。
当该通信装置1000用于执行图6中的方法600时，处理单元1100可用于执行方法600中的步骤650，收发单元1200可用于执行方法600中的步骤610、步骤630和步骤640。应理解，各单元执行上述相应步骤的具体过程在上述方法实施例中已经详细说明，为了简 洁，在此不再赘述。
还应理解，该通信装置1000为网络设备时，该通信装置1000中的收发单元可通过收发器实现，例如可对应于图9中示出的网络设备3000中的收发器3200，该通信装置1000中的处理单元1100可通过至少一个处理器实现，例如可对应于图9中示出的网络设备3000中的处理器3100。
还应理解，该通信装置1000为配置于网络设备中的芯片时，该通信装置1000中的收发单元1200可以通过输入/输出接口实现，该通信装置1000中的处理单元1100可以通过该芯片或芯片系统上集成的处理器、微处理器或集成电路等实现。
图8是本申请实施例提供的终端设备2000的结构示意图。该终端设备2000可应用于如图1所示的系统中，执行上述方法实施例中终端设备的功能。如图所示，该终端设备2000包括处理器2010和收发器2020。可选地，该终端设备2000还包括存储器2030。其中，处理器2010、收发器2002和存储器2030之间可以通过内部连接通路互相通信，传递控制和/或数据信号，该存储器2030用于存储计算机程序，该处理器2010用于从该存储器2030中调用并运行该计算机程序，以控制该收发器2020收发信号。可选地，终端设备2000还可以包括天线2040，用于将收发器2020输出的上行数据或上行控制信令通过无线信号发送出去。
上述处理器2010可以和存储器2030可以合成一个处理装置，处理器2010用于执行存储器2030中存储的程序代码来实现上述功能。具体实现时，该存储器2030也可以集成在处理器2010中，或者独立于处理器2010。该处理器2010可以与图7中的处理单元对应。
上述收发器2020可以与图7中的收发单元对应，也可以称为收发单元。收发器2020可以包括接收器(或称接收机、接收电路)和发射器(或称发射机、发射电路)。其中，接收器用于接收信号，发射器用于发射信号。
应理解，图8所示的终端设备2000能够实现图3至图6所示方法实施例中涉及终端设备的各个过程。终端设备2000中的各个模块的操作和/或功能，分别为了实现上述方法实施例中的相应流程。具体可参见上述方法实施例中的描述，为避免重复，此处适当省略详细描述。
上述处理器2010可以用于执行前面方法实施例中描述的由终端设备内部实现的动作，而收发器2020可以用于执行前面方法实施例中描述的终端设备向网络设备发送或从网络设备接收的动作。具体请见前面方法实施例中的描述，此处不再赘述。
可选地，上述终端设备2000还可以包括电源2050，用于给终端设备中的各种器件或电路提供电源。
除此之外，为了使得终端设备的功能更加完善，该终端设备2000还可以包括输入单元2060、显示单元2070、音频电路2080、摄像头2090和传感器2100等中的一个或多个，所述音频电路还可以包括扬声器2082、麦克风2084等。
图9是本申请实施例提供的网络设备的结构示意图，例如可以为基站的结构示意图。该基站3000可应用于如图1所示的系统中，执行上述方法实施例中网络设备的功能。如图所示，该基站3000可以包括一个或多个射频单元，如远端射频单元(remote radio unit，RRU)3100和一个或多个基带单元(BBU)(也可称为分布式单元(DU))3200。所述RRU 3100可以称为收发单元，与图9中的收发单元1100对应。可选地，该收发单元3100 还可以称为收发机、收发电路、或者收发器等等，其可以包括至少一个天线3101和射频单元3102。可选地，收发单元3100可以包括接收单元和发送单元，接收单元可以对应于接收器(或称接收机、接收电路)，发送单元可以对应于发射器(或称发射机、发射电路)。所述RRU 3100部分主要用于射频信号的收发以及射频信号与基带信号的转换，例如用于向终端设备发送指示信息。所述BBU 3200部分主要用于进行基带处理，对基站进行控制等。所述RRU 3100与BBU 3200可以是物理上设置在一起，也可以物理上分离设置的，即分布式基站。
所述BBU 3200为基站的控制中心，也可以称为处理单元，可以与图9中的处理单元1200对应，主要用于完成基带处理功能，如信道编码，复用，调制，扩频等等。例如所述BBU(处理单元)可以用于控制基站执行上述方法实施例中关于网络设备的操作流程，例如，生成上述指示信息等。
在一个示例中，所述BBU 3200可以由一个或多个单板构成，多个单板可以共同支持单一接入制式的无线接入网(如LTE网)，也可以分别支持不同接入制式的无线接入网(如LTE网，5G网或其他网)。所述BBU 3200还包括存储器3201和处理器3202。所述存储器3201用以存储必要的指令和数据。所述处理器3202用于控制基站进行必要的动作，例如用于控制基站执行上述方法实施例中关于网络设备的操作流程。所述存储器3201和处理器3202可以服务于一个或多个单板。也就是说，可以每个单板上单独设置存储器和处理器。也可以是多个单板共用相同的存储器和处理器。此外每个单板上还可以设置有必要的电路。
应理解，图9所示的基站3000能够实现图3至图6所示方法实施例中涉及网络设备的各个过程。基站3000中的各个模块的操作和/或功能，分别为了实现上述方法实施例中的相应流程。具体可参见上述方法实施例中的描述，为避免重复，此处适当省略详细描述。
上述BBU 3200可以用于执行前面方法实施例中描述的由网络设备内部实现的动作，而RRU 3100可以用于执行前面方法实施例中描述的网络设备向终端设备发送或从终端设备接收的动作。具体请见前面方法实施例中的描述，此处不再赘述。
应理解，图9所示出的基站3000仅为网络设备的一种可能的形态，而不应对本申请构成任何限定。本申请所提供的方法可适用于其他形态的网络设备。例如，包括AAU，还可以包括CU和/或DU，或者包括BBU和自适应无线单元(adaptive radio unit，ARU)，或BBU；也可以为客户终端设备(customer premises equipment，CPE)，还可以为其它形态，本申请对于网络设备的具体形态不做限定。
其中，CU和/或DU可以用于执行前面方法实施例中描述的由网络设备内部实现的动作，而AAU可以用于执行前面方法实施例中描述的网络设备向终端设备发送或从终端设备接收的动作。具体请见前面方法实施例中的描述，此处不再赘述。
本申请实施例还提供了一种处理装置，包括处理器和接口；所述处理器用于执行上述任一方法实施例中的方法。
应理解，上述处理装置可以是一个或多个芯片。例如，该处理装置可以是现场可编程门阵列(field programmable gate array，FPGA)，可以是专用集成芯片(application specific integrated circuit，ASIC)，还可以是系统芯片(system on chip，SoC)，还可以是中央处理器(central processor unit，CPU)，还可以是网络处理器(network processor，NP)，还可以是数字信号处理电路(digital signal processor，DSP)，还可以是微控制器(micro  controller unit，MCU)，还可以是可编程控制器(programmable logic device，PLD)或其他集成芯片。
在实现过程中，上述方法的各步骤可以通过处理器中的硬件的集成逻辑电路或者软件形式的指令完成。结合本申请实施例所公开的方法的步骤可以直接体现为硬件处理器执行完成，或者用处理器中的硬件及软件模块组合执行完成。软件模块可以位于随机存储器，闪存、只读存储器，可编程只读存储器或者电可擦写可编程存储器、寄存器等本领域成熟的存储介质中。该存储介质位于存储器，处理器读取存储器中的信息，结合其硬件完成上述方法的步骤。为避免重复，这里不再详细描述。
应注意，本申请实施例中的处理器可以是一种集成电路芯片，具有信号的处理能力。在实现过程中，上述方法实施例的各步骤可以通过处理器中的硬件的集成逻辑电路或者软件形式的指令完成。上述的处理器可以是通用处理器、数字信号处理器(DSP)、专用集成电路(ASIC)、现场可编程门阵列(FPGA)或者其他可编程逻辑器件、分立门或者晶体管逻辑器件、分立硬件组件。可以实现或者执行本申请实施例中的公开的各方法、步骤及逻辑框图。通用处理器可以是微处理器或者该处理器也可以是任何常规的处理器等。结合本申请实施例所公开的方法的步骤可以直接体现为硬件译码处理器执行完成，或者用译码处理器中的硬件及软件模块组合执行完成。软件模块可以位于随机存储器，闪存、只读存储器，可编程只读存储器或者电可擦写可编程存储器、寄存器等本领域成熟的存储介质中。该存储介质位于存储器，处理器读取存储器中的信息，结合其硬件完成上述方法的步骤。
可以理解，本申请实施例中的存储器可以是易失性存储器或非易失性存储器，或可包括易失性和非易失性存储器两者。其中，非易失性存储器可以是只读存储器(read-only memory，ROM)、可编程只读存储器(programmable ROM，PROM)、可擦除可编程只读存储器(erasable PROM，EPROM)、电可擦除可编程只读存储器(electrically EPROM，EEPROM)或闪存。易失性存储器可以是随机存取存储器(random access memory，RAM)，其用作外部高速缓存。通过示例性但不是限制性说明，许多形式的RAM可用，例如静态随机存取存储器(static RAM，SRAM)、动态随机存取存储器(dynamic RAM，DRAM)、同步动态随机存取存储器(synchronous DRAM，SDRAM)、双倍数据速率同步动态随机存取存储器(double data rate SDRAM，DDR SDRAM)、增强型同步动态随机存取存储器(enhanced SDRAM，ESDRAM)、同步连接动态随机存取存储器(synchlink DRAM，SLDRAM)和直接内存总线随机存取存储器(direct rambus RAM，DR RAM)。应注意，本文描述的系统和方法的存储器旨在包括但不限于这些和任意其它适合类型的存储器。
根据本申请实施例提供的方法，本申请还提供一种计算机程序产品，该计算机程序产品包括：计算机程序代码，当该计算机程序代码在计算机上运行时，使得该计算机执行图3至图6所示实施例中终端设备和网络设备分别执行的方法。
根据本申请实施例提供的方法，本申请还提供一种计算机可读介质，该计算机可读介质存储有程序代码，当该程序代码在计算机上运行时，使得该计算机执行图3至图6所示实施例中终端设备和网络设备分别执行的方法。
根据本申请实施例提供的方法，本申请还提供一种系统，其包括前述的一个或多个终端设备以及一个或多个网络设备。
上述各个装置实施例中网络设备与终端设备和方法实施例中的网络设备或终端设备 完全对应，由相应的模块或单元执行相应的步骤，例如通信单元(收发器)执行方法实施例中接收或发送的步骤，除发送、接收外的其它步骤可以由处理单元(处理器)执行。具体单元的功能可以参考相应的方法实施例。其中，处理器可以为一个或多个。
在本说明书中使用的术语“部件”、“模块”、“系统”等用于表示计算机相关的实体、硬件、固件、硬件和软件的组合、软件、或执行中的软件。例如，部件可以是但不限于，在处理器上运行的进程、处理器、对象、可执行文件、执行线程、程序和/或计算机。通过图示，在计算设备上运行的应用和计算设备都可以是部件。一个或多个部件可驻留在进程和/或执行线程中，部件可位于一个计算机上和/或分布在2个或更多个计算机之间。此外，这些部件可从在上面存储有各种数据结构的各种计算机可读介质执行。部件可例如根据具有一个或多个数据分组(例如来自与本地系统、分布式系统和/或网络间的另一部件交互的二个部件的数据，例如通过信号与其它系统交互的互联网)的信号通过本地和/或远程进程来通信。
本领域普通技术人员可以意识到，结合本文中所公开的实施例描述的各种说明性逻辑块(illustrative logical block)和步骤(step)，能够以电子硬件、或者计算机软件和电子硬件的结合来实现。这些功能究竟以硬件还是软件方式来执行，取决于技术方案的特定应用和设计约束条件。专业技术人员可以对每个特定的应用来使用不同方法来实现所描述的功能，但是这种实现不应认为超出本申请的范围。
所属领域的技术人员可以清楚地了解到，为描述的方便和简洁，上述描述的系统、装置和单元的具体工作过程，可以参考前述方法实施例中的对应过程，在此不再赘述。
在本申请所提供的几个实施例中，应该理解到，所揭露的系统、装置和方法，可以通过其它的方式实现。例如，以上所描述的装置实施例仅仅是示意性的，例如，所述单元的划分，仅仅为一种逻辑功能划分，实际实现时可以有另外的划分方式，例如多个单元或组件可以结合或者可以集成到另一个系统，或一些特征可以忽略，或不执行。另一点，所显示或讨论的相互之间的耦合或直接耦合或通信连接可以是通过一些接口，装置或单元的间接耦合或通信连接，可以是电性，机械或其它的形式。
所述作为分离部件说明的单元可以是或者也可以不是物理上分开的，作为单元显示的部件可以是或者也可以不是物理单元，即可以位于一个地方，或者也可以分布到多个网络单元上。可以根据实际的需要选择其中的部分或者全部单元来实现本实施例方案的目的。
另外，在本申请各个实施例中的各功能单元可以集成在一个处理单元中，也可以是各个单元单独物理存在，也可以两个或两个以上单元集成在一个单元中。
在上述实施例中，各功能单元的功能可以全部或部分地通过软件、硬件、固件或者其任意组合来实现。当使用软件实现时，可以全部或部分地以计算机程序产品的形式实现。所述计算机程序产品包括一个或多个计算机指令(程序)。在计算机上加载和执行所述计算机程序指令(程序)时，全部或部分地产生按照本申请实施例所述的流程或功能。所述计算机可以是通用计算机、专用计算机、计算机网络、或者其他可编程装置。所述计算机指令可以存储在计算机可读存储介质中，或者从一个计算机可读存储介质向另一个计算机可读存储介质传输，例如，所述计算机指令可以从一个网站站点、计算机、服务器或数据中心通过有线(例如同轴电缆、光纤、数字用户线(digital subscriber line，DSL))或无线(例如红外、无线、微波等)方式向另一个网站站点、计算机、服务器或数据中心进行传输。所述计算机可读存储介质可以是计算机能够存取的任何可用介质或者是包含一个或 多个可用介质集成的服务器、数据中心等数据存储设备。所述可用介质可以是磁性介质，(例如，软盘、硬盘、磁带)、光介质(例如，高密度数字视频光盘(digital video disc，DVD))、或者半导体介质(例如固态硬盘(solid state disk，SSD))等。
所述功能如果以软件功能单元的形式实现并作为独立的产品销售或使用时，可以存储在一个计算机可读取存储介质中。基于这样的理解，本申请的技术方案本质上或者说对现有技术做出贡献的部分或者该技术方案的部分可以以软件产品的形式体现出来，该计算机软件产品存储在一个存储介质中，包括若干指令用以使得一台计算机设备(可以是个人计算机，服务器，或者网络设备等)执行本申请各个实施例所述方法的全部或部分步骤。而前述的存储介质包括：U盘、移动硬盘、只读存储器(read-only memory，ROM)、随机存取存储器(random access memory，RAM)、磁碟或者光盘等各种可以存储程序代码的介质。
以上所述，仅为本申请的具体实施方式，但本申请的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本申请揭露的技术范围内，可轻易想到变化或替换，都应涵盖在本申请的保护范围之内。因此，本申请的保护范围应以所述权利要求的保护范围为准。

Claims (34)

  1. 一种信道测量方法，其特征在于，包括：
    生成第一指示信息，所述第一指示信息用于指示对应于P个发射端口的P组加权系数，所述P个发射端口中每个发射端口的参考信号基于一时延向量和/或一角度向量对参考信号进行预编码得到，所述P个发射端口中每个发射端口对应的加权系数以及每个发射端口对应的时延向量和/或角度向量用于构建预编码矩阵；其中，对应于所述P个发射端口中第p个发射端口的第p组加权系数通过对所述第p个发射端口与终端设备的R个接收端口间的信道信息进行时域变换得到，所述第p个发射端口是所述P个发射端口中的任意一个发射端口，0≤p≤P-1，P≥1，R≥1，p、P和R均为整数；
    发送所述第一指示信息。
  2. 如权利要求1所述的方法，其特征在于，所述P组加权系数中的每组加权系数包括R’个加权系数，所述第p组加权系数是通过对所述第p个发射端口与所述R个接收端口中的一个或多个接收端口间的信道信息进行时域变换得到；R≥R’≥1，R’为整数。
  3. 如权利要求2所述的方法，其特征在于，所述P组加权系数中的每组加权系数包括对应于所述R个接收端口的R个加权系数，所述第p组加权系数中的第r个加权系数通过对所述第p个发射端口与所述R个接收端口中的第r个接收端口间的信道信息进行时域变换得到。
  4. 如权利要求3所述的方法，其特征在于，所述方法还包括：
    对所述第p个发射端口与所述第r个接收端口间的信道信息所确定的向量进行时域变换，得到变换后的向量，所述第p组加权系数中的第r个加权系数是经所述时域变换得到的向量中的第n p,r个值；其中，所述第p个发射端口与所述第r个接收端口间的信道信息所确定的向量包括N个值，所述N个值包括用于承载所述第p个发射端口的参考信号的N个频域单元分别对应的信道信息，0≤n p,r≤N-1，N≥1，n p,r和N均为整数。
  5. 如权利要求4所述的方法，其特征在于，所述n p,r为预定义值。
  6. 如权利要求5所述的方法，其特征在于，n p,r＝0。
  7. 如权利要求4所述的方法，其特征在于，所述第一指示信息还用于指示与所述第p个发射端口和所述第r个接收端口间的信道对应的n p,r的值。
  8. 如权利要求4至7中任一项所述的方法，其特征在于，所述方法还包括：
    基于预先确定的滤波系数，对所述变换后的向量进行滤波处理，得到所述第p组加权系数中的第r个加权系数；其中，所述滤波系数包括N个元素，所述N个元素中包括一个非零元素和N-1个零元素，所述非零元素为所述N个元素中的第n p,r个元素。
  9. 如权利要求1至8中任一项所述的方法，其特征在于，所述时域变换包括：快速傅里叶逆变换IFFT或离散傅里叶逆变换IDFT。
  10. 一种信道测量方法，其特征在于，包括：
    生成第二指示信息，所述第二指示信息用于指示对应于P个发射端口的P组加权系数，所述P个发射端口中每个发射端口的参考信号至少基于一时延向量对参考信号进行预编码得到，所述P个发射端口中每个发射端口对应的加权系数以及每个发射端口对应的时延向量用于构建预编码矩阵；其中，对应于所述P个发射端口中的第p个发射端口的第p组 加权系数是对一个或多个频域单元组的信道信息分别进行滤波所得的多个值之和，所述一个或多个频域单元组中的每个频域单元组包括多个频域单元，且所述一个或多个频域单元组所包括的频域单元的总数目是是用于承载所述第p个发射端口的参考信号的频域单元的数目，所述第p个发射端口是所述P个发射端口中的任意一个发射端口，0≤p≤P-1，P≥1，p、P均为整数；
    发送所述第二指示信息。
  11. 如权利要求10所述的方法，其特征在于，所述方法还包括：
    基于预先确定的与所述第p个发射端口对应的滤波系数，分别对所述一个或多个频域单元组的信道信息进行滤波，以得到滤波后的值；
    将所述一个或多个频域单元组的滤波后的值求和，得到对应于所述第p个发射端口的加权系数。
  12. 如权利要求11所述的方法，其特征在于，所述方法还包括：
    基于与所述第p个发射端口对应的时延τ p或时延τ p的相关参数，确定所述滤波系数，其中每个时延对应于一个时延向量。
  13. 如权利要求12所述的方法，其特征在于，所述滤波系数为：
    Figure PCTCN2019114491-appb-100001
    其中，
    Figure PCTCN2019114491-appb-100002
    其中，
    Figure PCTCN2019114491-appb-100003
    为相关矩阵，表示用于承载所述第p个发射端口的参考信号的一个频域单元组中各频域单元之间的相关性；
    Figure PCTCN2019114491-appb-100004
    为修正值，用于对
    Figure PCTCN2019114491-appb-100005
    进行修正，
    Figure PCTCN2019114491-appb-100006
    为与所述第p个发射端口对应的时延τ p或时延τ p的相关参数，N表示用于承载所述第p个发射端口的参考信号的频域单元的数目，N＞1且为整数；
    Figure PCTCN2019114491-appb-100007
    为对
    Figure PCTCN2019114491-appb-100008
    进行修正得到的相关矩阵；SNR为信号噪声比；I表示单位阵。
  14. 如权利要求10至13中任一项所述的方法，其特征在于，所述方法还包括：
    接收第三指示信息，所述第三指示信息用于指示与所述P个发射端口中每个发射端口对应的时延或时延的相关参数，每个时延对应于一个时延向量。
  15. 如权利要求14所述的方法，其特征在于，所述第三指示信息对所述P个发射端口中每个发射端口对应的时延指示为与每个发射端口对应的时延。
  16. 如权利要求14所述的方法，其特征在于，所述第三指示信息对所述P个发射端口中每个发射端口对应的时延的相关参数的指示为：所述P个端口中的第一发射端口对应 的时延τ 0，以及所述P个发射端口中除所述第一发射端口之外的其余端口对应的时延与所述第一发射端口对应的时延的差值Δτ。
  17. 一种通信装置，其特征在于，包括：
    处理单元，用于生成第一指示信息，所述第一指示信息用于指示对应于P个发射端口的P组加权系数，所述P个发射端口中每个发射端口的参考信号基于一时延向量和/或一角度向量对参考信号进行预编码得到，所述P个发射端口中每个发射端口对应的加权系数以及每个发射端口对应的时延向量和/或角度向量用于构建预编码矩阵；其中，对应于所述P个发射端口中第p个发射端口的第p组加权系数通过对所述第p个发射端口与终端设备的R个接收端口间的信道信息进行时域变换得到，所述第p个发射端口是所述P个发射端口中的任意一个发射端口，0≤p≤P-1，P≥1，R≥1，p、P和R均为整数；
    收发单元，用于发送所述第一指示信息。
  18. 如权利要求17所述的装置，其特征在于，所述P组加权系数中的每组加权系数包括R’个加权系数，所述第p组加权系数是通过对所述第p个发射端口与所述R个接收端口中的一个或多个接收端口间的信道信息进行时域变换得到；R≥R’≥1，R’为整数。
  19. 如权利要求18所述的装置，其特征在于，所述P组加权系数中的每组加权系数包括对应于所述R个接收端口的R个加权系数，所述第p组加权系数中的第r个加权系数通过对所述第p个发射端口与所述R个接收端口中的第r个接收端口间的信道信息进行时域变换得到。
  20. 如权利要求19所述的装置，其特征在于，所述处理单元还用于对所述第p个发射端口与所述第r个接收端口间的信道信息所确定的向量进行时域变换，得到变换后的向量，所述第p组加权系数中的第r个加权系数是经所述时域变换得到的向量中的第n p,r个值；其中，所述第p个发射端口与所述第r个接收端口间的信道信息所确定的向量包括N个值，所述N个值包括用于承载所述第p个发射端口的参考信号的N个频域单元分别对应的信道信息，0≤n p,r≤N-1，N≥1，n p,r和N均为整数。
  21. 如权利要求20所述的装置，其特征在于，n p,r为预定义值。
  22. 如权利要求21所述的装置，其特征在于，n p,r＝0。
  23. 如权利要求20所述的装置，其特征在于，所述第一指示信息还用于指示与所述第p个发射端口和所述第r个接收端口间的信道对应的n p,r的值。
  24. 如权利要求20至23中任一项所述的装置，其特征在于，所述处理单元还用于基于预先确定的滤波系数，对所述变换后的向量进行滤波处理，得到所述第p组加权系数中的第r个加权系数；其中，所述滤波系数包括N个元素，所述N个元素中包括一个非零元素和N-1个零元素，所述非零元素为所述N个元素中的第n p,r个元素。
  25. 如权利要求17至24中任一项所述的装置，其特征在于，所述时域变换包括：快速傅里叶逆变换IFFT或离散傅里叶逆变换IDFT。
  26. 一种通信装置，其特征在于，包括：
    处理单元，用于生成第二指示信息，所述第二指示信息用于指示对应于P个发射端口的P组加权系数，所述P个发射端口中每个发射端口的参考信号至少基于一时延向量对参考信号进行预编码得到，所述P个发射端口中每个发射端口对应的加权系数以及每个发射端口对应的时延向量用于构建预编码矩阵；其中，对应于所述P个发射端口中的第p个发射端口的第p组加权系数是对一个或多个频域单元组的信道信息分别进行滤波所得的多 个值之和，所述一个或多个频域单元组中的每个频域单元组包括多个频域单元，且所述一个或多个频域单元组所包括的频域单元的总数目是是用于承载所述第p个发射端口的参考信号的频域单元的数目，所述第p个发射端口是所述P个发射端口中的任意一个发射端口，0≤p≤P-1，P≥1，p、P均为整数；
    收发单元，用于发生所述第二指示信息。
  27. 如权利要求26所述的装置，其特征在于，所述处理单元还用于基于预先确定的与所述第p个发射端口对应的滤波系数，分别对所述一个或多个频域单元组的信道信息进行滤波，以得到滤波后的值；并用于将所述一个或多个频域单元组的滤波后的值求和，得到对应于所述第p个发射端口的加权系数。
  28. 如权利要求27所述的装置，其特征在于，所述处理单元还用于基于与所述第p个发射端口对应的时延τ p或时延τ p的相关参数，确定所述滤波系数，其中每个时延对应于一个时延向量。
  29. 如权利要求28所述的装置，其特征在于，所述滤波系数为：
    Figure PCTCN2019114491-appb-100009
    其中，
    Figure PCTCN2019114491-appb-100010
    其中，
    Figure PCTCN2019114491-appb-100011
    为相关矩阵，表示用于承载所述第p个发射端口的参考信号的一个频域单元组中各频域单元之间的相关性；
    Figure PCTCN2019114491-appb-100012
    为修正值，用于对
    Figure PCTCN2019114491-appb-100013
    进行修正，
    Figure PCTCN2019114491-appb-100014
    为与所述第p个发射端口对应的时延τ p或时延τ p的相关参数，N表示用于承载所述第p个发射端口的参考信号的频域单元的数目，N＞1且为整数；
    Figure PCTCN2019114491-appb-100015
    为对
    Figure PCTCN2019114491-appb-100016
    进行修正得到的相关矩阵；SNR为信号噪声比；I表示单位阵。
  30. 如权利要求26至29中任一项所述的装置，其特征在于，所述收发单元还用于接收第三指示信息，所述第三指示信息用于指示与所述P个发射端口中每个发射端口对应的时延或时延的相关参数，每个时延对应于一个时延向量。
  31. 如权利要求30所述的装置，其特征在于，所述第三指示信息对所述P个发射端口中每个发射端口对应的时延指示为与每个发射端口对应的时延。
  32. 如权利要求30所述的装置，其特征在于，所述第三指示信息对所述P个发射端口中每个发射端口对应的时延的相关参数的指示为：所述P个端口中的第一发射端口对应的时延τ 0，以及所述P个发射端口中除所述第一发射端口之外的其余端口对应的时延与所述第一发射端口对应的时延的差值Δτ。
  33. 一种通信装置，其特征在于，包括至少一个处理器，所述至少一个处理器用于执 行存储器中存储的计算机程序，以使得所述通信装置实现如权利要求1至16中任一项所述的方法。
  34. 一种计算机可读介质，其特征在于，包括计算机程序，当所述计算机程序在计算机上运行时，使得所述计算机执行如权利要求1至16中任一项所述的方法。
PCT/CN2019/114491 2019-10-30 2019-10-30 一种信道测量方法和通信装置 WO2021081847A1 (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN201980101549.0A CN114600384B (zh) 2019-10-30 2019-10-30 一种信道测量方法和通信装置
PCT/CN2019/114491 WO2021081847A1 (zh) 2019-10-30 2019-10-30 一种信道测量方法和通信装置

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2019/114491 WO2021081847A1 (zh) 2019-10-30 2019-10-30 一种信道测量方法和通信装置

Publications (1)

Publication Number Publication Date
WO2021081847A1 true WO2021081847A1 (zh) 2021-05-06

Family

ID=75715650

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2019/114491 WO2021081847A1 (zh) 2019-10-30 2019-10-30 一种信道测量方法和通信装置

Country Status (2)

Country Link
CN (1) CN114600384B (zh)
WO (1) WO2021081847A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114448757A (zh) * 2022-01-21 2022-05-06 华中科技大学 Fdd大规模mimo系统中基于信道部分互易性的信道估计方法
WO2023131256A1 (zh) * 2022-01-06 2023-07-13 维沃移动通信有限公司 信道测量方法、终端及网络侧设备

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117938581A (zh) * 2022-10-24 2024-04-26 华为技术有限公司 一种信道信息获取的方法和装置

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103746779A (zh) * 2013-12-31 2014-04-23 上海华为技术有限公司 一种信道状态信息测量、参考信号的发送方法和装置
CN105322994A (zh) * 2014-08-05 2016-02-10 上海贝尔股份有限公司 一种进行3d波束成形的方法、装置和系统
CN106033990A (zh) * 2015-03-13 2016-10-19 电信科学技术研究院 一种信道状态信息反馈方法、获取方法及装置
CN107370558A (zh) * 2016-05-13 2017-11-21 北京华为数字技术有限公司 一种信道信息发送方法、数据发送方法和设备
US20190007112A1 (en) * 2017-06-29 2019-01-03 Telefonaktiebolaget Lm Ericsson (Publ) High Spatial Resolution Beam Space CSI Feedback

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10200227B2 (en) * 2002-05-14 2019-02-05 Genghiscomm Holdings, LLC Pre-coding in multi-user MIMO
CN105245310B (zh) * 2014-07-09 2020-01-14 中兴通讯股份有限公司 一种下行导频信号的处理方法及系统
CN107395256B (zh) * 2016-05-12 2021-02-09 华为技术有限公司 一种信道状态信息反馈方法、设备及系统
CN106452676B (zh) * 2016-10-14 2019-12-06 上海华为技术有限公司 一种多点协同传输的方法及相关设备
CN108282321B (zh) * 2017-01-06 2022-03-29 华为技术有限公司 一种信息指示的方法、网络设备和终端设备
US11418379B2 (en) * 2017-06-09 2022-08-16 Lg Electronics Inc. Method for transmitting/receiving reference signal in wireless communication system, and device therefor
CN114448477A (zh) * 2017-06-16 2022-05-06 华为技术有限公司 通信方法、通信装置和系统
CN109474315B (zh) * 2017-09-07 2021-06-01 华为技术有限公司 一种指示及确定预编码矩阵的方法和设备
CN109495149B (zh) * 2017-09-11 2021-10-15 华为技术有限公司 通信方法、网络设备、终端设备和系统
CN109802801B (zh) * 2017-11-17 2021-12-14 华为技术有限公司 发送和接收信号的方法、装置和系统
CN110086732B (zh) * 2018-01-25 2020-09-29 华为技术有限公司 一种信道估计方法和装置

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103746779A (zh) * 2013-12-31 2014-04-23 上海华为技术有限公司 一种信道状态信息测量、参考信号的发送方法和装置
CN105322994A (zh) * 2014-08-05 2016-02-10 上海贝尔股份有限公司 一种进行3d波束成形的方法、装置和系统
CN106033990A (zh) * 2015-03-13 2016-10-19 电信科学技术研究院 一种信道状态信息反馈方法、获取方法及装置
CN107370558A (zh) * 2016-05-13 2017-11-21 北京华为数字技术有限公司 一种信道信息发送方法、数据发送方法和设备
US20190007112A1 (en) * 2017-06-29 2019-01-03 Telefonaktiebolaget Lm Ericsson (Publ) High Spatial Resolution Beam Space CSI Feedback

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023131256A1 (zh) * 2022-01-06 2023-07-13 维沃移动通信有限公司 信道测量方法、终端及网络侧设备
CN114448757A (zh) * 2022-01-21 2022-05-06 华中科技大学 Fdd大规模mimo系统中基于信道部分互易性的信道估计方法

Also Published As

Publication number Publication date
CN114600384B (zh) 2023-09-12
CN114600384A (zh) 2022-06-07

Similar Documents

Publication Publication Date Title
CN111342912B (zh) 一种信道测量方法和通信装置
WO2020125534A1 (zh) 一种信道测量方法和通信装置
CN112751592B (zh) 上报信道状态信息的方法和通信装置
JP7238167B2 (ja) プリコーディング行列表示及び決定方法、及び通信装置
WO2021037200A1 (zh) 信道测量的方法和通信装置
CN111342913B (zh) 一种信道测量方法和通信装置
WO2021063178A1 (zh) 信道测量方法和通信装置
WO2021081847A1 (zh) 一种信道测量方法和通信装置
CN112751598B (zh) 一种预编码矩阵的处理方法和通信装置
WO2020244496A1 (zh) 一种信道测量方法和通信装置
CN112312464A (zh) 上报信道状态信息的方法和通信装置
CN115315906B (zh) 一种信道测量方法和通信装置
WO2021159309A1 (zh) 一种信道测量方法和通信装置
WO2024027394A1 (zh) 一种通信方法及装置
US20220271900A1 (en) Method for configuring transmit port of downlink reference signal and communication apparatus
US20230019630A1 (en) Update Method and Communications Apparatus
US20230013510A1 (en) Method for indicating channel state information csi measurement and communication apparatus
EP4187812A1 (en) Channel measurement method and communication apparatus
CN116743217A (zh) 信道状态信息的反馈方法和通信装置
WO2021159537A1 (zh) 一种信道状态信息反馈方法及通信装置
WO2022227976A1 (zh) 通信方法和通信装置
WO2021146938A1 (zh) 用于确定下行信道状态信息的方法和装置
WO2021146961A1 (zh) 用于确定下行信道状态信息的方法和装置
WO2024001744A1 (zh) 一种信道状态信息的上报方法及通信装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19951231

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 19951231

Country of ref document: EP

Kind code of ref document: A1