Channel State Information Feedback Method and Apparatus Thereof

Abstract

Embodiments of this application disclose a channel state information feedback method and apparatus. This method includes: a step in which a terminal device determines codebook indication information corresponding to a data transmission layer based on the length of a time domain (TD) basis vector or the length of a Doppler domain (DD) basis vector and codebook parameters set by a network-side device; and a step in which the terminal device transmits channel state information (CSI) including the codebook indication information to the network-side device, where the codebook indication information is used to instruct the network-side device to determine precoding matrices corresponding to different times. By implementing the embodiments of this application, the length of the TD basis vector or the length of the DD basis vector can be determined, and this length can be used to determine the TD basis vector or the DD basis vector used in the codebook. As a result, a time domain basis vector or a Doppler domain basis vector can be introduced based on the Rel-16 or 17 Type II codebook, and preset codes corresponding to different times can be determined. Moreover, not only can redundant setting of codebook parameters or redundant reporting of codebook parameters be avoided, but signaling overhead can also be reduced.

Description

Technical Field

[0001] This application relates to the field of communication technologies, and in particular, to a channel state information feedback method and apparatus.

Background Art

[0002] For a terminal device moving at medium to high speeds, due to the rapid change of the channel in the time domain, the channel state information (CSI) is still fed back based on the conventional Type II codebook, and the fed-back CSI does not match the current channel information, resulting in a decrease in system performance. Therefore, how to match the CSI fed back from a terminal device in a medium to high speed moving scenario with the current channel information is an issue that needs to be solved urgently.

Summary of the Invention

Problems to be Solved by the Invention

[0003] Embodiments of this application provide a channel state information feedback method and its apparatus. By determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector, this length can be used to determine the TD basis vector or the DD basis vector used in the codebook. Thereby, a time domain basis vector or a Doppler domain basis vector can be introduced based on the Rel-16 or 17 Type II codebook, and not only can preset codes corresponding to different times be determined, but also redundant configuration of codebook parameters or redundant reporting of codebook parameters can be avoided, and signaling overhead can be reduced.

[0004] According to a first aspect, embodiments of this application provide a channel state information feedback method, which is executed by a terminal device, and the method includes Determining codebook indication information corresponding to a data transmission layer based on the length of a time domain (TD) basis vector or the length of a Doppler domain (DD) basis vector and codebook parameters configured by a network-side device; Transmitting channel state information (CSI) including the codebook indication information to the network-side device, where the codebook indication information is used to instruct the network-side device to determine precoding matrices corresponding to different times.

[0005] In this technical solution, by determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector, this length can be used to determine the TD basis vector or the DD basis vector used in the codebook. Thereby, the time domain basis vector or the Doppler domain basis vector is introduced based on the Rel-16 or 17 Type II codebook, enabling precoding calculation or prediction for future times. As a result, the calculated or predicted preset code can be matched with the channels at corresponding future times, and preset codes corresponding to different times can be determined. Moreover, redundant setting of codebook parameters or redundant reporting of codebook parameters can be avoided, and signaling setting overhead or reporting feedback overhead can be reduced.

[0006] In one implementation form, the step of determining codebook indication information corresponding to a data transmission layer based on the length of a time domain (TD) basis vector or the length of a Doppler domain (DD) basis vector and codebook parameters configured by a network-side device includes: Determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector; Determining codebook indication information corresponding to the data transmission layer based on the length and the codebook parameters configured by the network-side device.

[0007] In one implementation form, the step of determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector includes the step of determining the length of the TD basis vector or the length of the DD basis vector based on a first parameter set by the network-side device.

[0008] In a possible implementation form, the first parameter is the number of channel state information reference signal (CSI-RS) resources or the number of CSI-RS resources within the CSI-RS measurement window, and the step of determining the length of the TD basis vector or the length of the DD basis vector based on the first parameter set by the network-side device includes the step of determining that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window, or the step of determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources set by the network-side device, or the step of determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources within the CSI-RS measurement window set by the network-side device, or the step of determining that the length of the TD basis vector or the length of the DD basis vector is

Number

[0009] In one possible implementation, the first parameter is the size of the CSI-RS measurement window and the interval between adjacent CSI measurement times. Based on the first parameter set by the network-side device, the step of determining the length of the TD basis vector or the length of the DD basis vector is that the length of the TD basis vector or the length of the DD basis vector is

Number

[0010] In one possible implementation, the first parameter is the number of CSI measurements or the number of CSI measurements within the CSI-RS measurement window. Based on the first parameter set by the network-side device, the step of determining the length of the TD basis vector or the length of the DD basis vector is determining that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI measurements set by the network-side device or the number of CSI measurements within the CSI-RS measurement window, or determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements set by the network-side device, or determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements within the CSI-RS measurement window set by the network-side device, or the length of the TD basis vector or the length of the DD basis vector is

Number

[0011] In a possible implementation form, the first parameter is parameter W. Based on the first parameter set by the network-side device, the step of determining the length of the TD basis vector or the length of the DD basis vector is the length of the TD basis vector or the length of the DD basis vector is

Number

Number

Number

Number

[0012] In a possible implementation form, the method includes a step of determining the compression unit C in the time domain. u It further includes the step of determining .

[0013] In a possible implementation form, the compression unit C u is αT c where α is an integer less than or equal to 1, and T c is the channel coherence time, or the compression unit C u is the measurement period of the CSI-RS resource, or the compression unit C u is βd1, where β is an integer greater than or equal to 1, and d1 is the measurement interval between adjacent CSIs, or the compression unit C u is βd2, where β is an integer greater than or equal to 1, and d2 is the maximum interval or minimum interval between adjacent CSI measurements, or the average value of multiple adjacent CSI measurement intervals.

[0014] In one implementation form, the step of determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector includes the step of determining the length of the TD basis vector or the length of the DD basis vector based on the Doppler offset information and Doppler spread estimated by the terminal device using CSI-RS.

[0015] In one implementation form, the step of determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector includes the step of receiving the length of the TD basis vector or the length of the DD basis vector set by the network side device.

[0016] In one implementation form, the codebook indication information includes at least one combination of one or more of a matrix composed of at least one spatial domain (SD) basis vector, a combination coefficient matrix, a matrix composed of at least one frequency domain (FD) basis vector, and a matrix composed of at least one TD basis vector or DD basis vector.

[0017] According to a second aspect, an embodiment of the present application provides another channel state information feedback method, which is executed by a network-side device, and the method includes: determining a length of a time domain (TD) basis vector or a length of a Doppler domain (DD) basis vector; setting codebook parameters for a terminal device; sending the length of the TD basis vector or the length of the DD basis vector and the codebook parameters to the terminal device; receiving, by the terminal device, codebook indication information corresponding to a data transmission layer determined by the length and the codebook parameters; and determining, based on the codebook indication information, a precoding matrix corresponding to different times.

[0018] In this technical solution, by determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector, this length can be used to determine the TD basis vector or the DD basis vector used in the codebook, thereby introducing the time domain basis vector or the Doppler domain basis vector based on the Rel-16 or 17 Type II codebook, realizing precoding calculation or prediction for future times, thereby matching the calculated or predicted preset code with the channel at the corresponding future time, not only being able to determine the preset codes corresponding to different times, but also being able to avoid redundant setting of codebook parameters or redundant reporting of codebook parameters, and reducing signaling setting overhead or reporting feedback overhead.

[0019] In one implementation form, the step of determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector includes: determining the length of the TD basis vector or the length of the DD basis vector based on a first parameter set by the network-side device.

[0020] In a possible implementation form, the first parameter is the number of channel state information reference signal (CSI-RS) resources or the number of CSI-RS resources within the CSI-RS measurement window. Based on the first parameter set by the network-side device, the step of determining the length of the TD basis vector or the length of the DD basis vector is the step of determining that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window, or the step of determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources set by the network-side device, or the step of determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources within the CSI-RS measurement window set by the network-side device, or the length of the TD basis vector or the length of the DD basis vector is

Number

[0021] In a possible implementation form, the first parameter is the size of the CSI-RS measurement window and the interval between adjacent CSI measurement times. Based on the first parameter set by the network-side device, the step of determining the length of the TD basis vector or the length of the DD basis vector is that the length of the TD basis vector or the length of the DD basis vector is

Number

[0022] In one possible implementation, the first parameter is a number of CSI measurements or a number of CSI measurements in a CSI-RS measurement window, and the step of determining a length of a TD basis vector or a length of a DD basis vector based on the first parameter set by the network side device includes a step of determining that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI measurements or the number of CSI measurements in a CSI-RS measurement window set by the network side device, or a step of determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements set by the network side device, or a step of determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements in a CSI-RS measurement window set by the network side device, or a step of determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements in a CSI-RS measurement window set by the network side device.

number

[0023] In one possible implementation, the first parameter is a parameter W, and the step of determining the length of the TD basis vector or the length of the DD basis vector based on the first parameter set by the network side device includes: determining the length of the TD basis vector or the length of the DD basis vector based on the first parameter set by the network side device;

number

Number

Number

Number

[0024] In a possible implementation form, the method further includes a step of determining the compression unit C u in the time domain.

[0025] In a possible implementation form, the compression unit C u is αT c where α is an integer less than or equal to 1, and the T c is the channel coherence time, or the compression unit C u is the measurement period of the CSI-RS resource, or the compression unit C u is βd1, where β is an integer greater than or equal to 1, and d1 is the measurement interval between adjacent CSIs, or the compression unit C u is βd2, where β is an integer greater than or equal to 1, and d2 is the maximum or minimum interval between adjacent CSI measurements, or the average value of multiple adjacent CSI measurement intervals.

[0026] In one implementation, the step of determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector includes determining the length of the TD basis vector or the length of the DD basis vector based on the Doppler offset information and the Doppler spread reported by the terminal device.

[0027] In one implementation, the step of determining the precoding matrix corresponding to different times based on the codebook indication information includes determining the precoding matrix corresponding to different times using a codebook structure or a precoding matrix indicator (PMI) prediction algorithm based on the codebook indication information and the method for determining the length of the TD basis vector or the length of the DD basis vector.

[0028] In a third aspect, the embodiments of the present application provide a communication device having some or all of the functions of the terminal device in the method described in the first aspect above. For example, the functions of the communication device may include the functions in some or all of the embodiments of the present application, or may include the function of executing any one of the embodiments of the present application alone. The functions may be implemented by hardware or by executing corresponding software by the hardware. The hardware or software includes one or more units or modules corresponding to the above functions.

[0029] In one implementation, the configuration of this communication device may include a transceiver module and a processing module. The processing module is configured to support the communication device to execute the corresponding functions in the above method. The transceiver module is used to support communication between the communication device and other devices. The communication device may further include a storage module for coupling with the transceiver module and the processing module. This storage module stores the computer programs and data required by the communication device.

[0030] As an example, the processing module may be a processor, the transceiver module may be a transceiver or a communication interface, and the storage module may be a memory.

[0031] In a fourth aspect, an embodiment of the present application provides another communication device having some or all of the functions of realizing the network-side device in the example of the method described in the second aspect above. For example, the functions of the communication device may include the functions in some or all of the embodiments of the present application, or may include the function of executing any one of the embodiments of the present application alone. The said function may be realized by hardware, or may be realized by executing corresponding software by hardware. The said hardware or software includes one or more units or modules corresponding to the above functions.

[0032] In one implementation form, the configuration of this communication device may include a transceiver module and a processing module, and the processing module is configured to support the communication device to execute the corresponding functions in the above method. The transceiver module is used to support communication between the communication device and other devices. The communication device may further include a storage module for coupling with the transceiver module and the processing module, and this storage module stores the computer programs and data required by the communication device.

[0033] As an example, the processing module may be a processor, the transceiver module may be a transceiver or a communication interface, and the storage module may be a memory.

[0034] In a fifth aspect, an embodiment of the present application provides a communication device including a processor, and when the processor calls a computer program in a memory, the method described in the first aspect above is executed.

[0035] In a sixth aspect, an embodiment of the present application provides a communication device including a processor, and when the processor calls a computer program in a memory, the method described in the second aspect is executed.

[0036] In a seventh aspect, an embodiment of the present application provides a communication device including a processor and a memory, in which a computer program is stored in the memory, and the processor causes the communication device to execute the method in the first aspect by executing the computer program stored in the memory.

[0037] In an eighth aspect, an embodiment of the present application provides a communication device including a processor and a memory, in which a computer program is stored in the memory, and the processor causes the communication device to execute the method in the second aspect by executing the computer program stored in the memory.

[0038] In a ninth aspect, an embodiment of the present application provides a communication device including a processor and an interface circuit, the interface circuit is used to receive code instructions and send them to the processor, and the processor is used to cause the communication device to execute the method in the first aspect by executing the code instructions.

[0039] In a tenth aspect, an embodiment of the present application provides a communication device including a processor and an interface circuit, the interface circuit is used to receive code instructions and send them to the processor, and the processor is used to cause the communication device to execute the method in the second aspect by executing the code instructions.

[0040] According to the 11th aspect, an embodiment of the present application includes the communication device described in the 3rd aspect and the communication device described in the 4th aspect, or includes the communication device described in the 5th aspect and the communication device described in the 6th aspect, or includes the communication device described in the 7th aspect and the communication device described in the 8th aspect, or includes the communication device described in the 9th aspect and the communication device described in the 10th aspect, and provides a channel state information feedback system.

[0041] In the 12th aspect, an embodiment of the present invention provides a computer-readable storage medium for storing instructions used in the above terminal device, and when the instructions are executed, the method described in the 1st aspect is caused to be executed by the terminal device.

[0042] In the 13th aspect, an embodiment of the present invention provides a readable storage medium for storing instructions used on the network device side, and when the instructions are executed, the method described in the 2nd aspect is caused to be executed by the network device side.

[0043] In the 14th aspect, the present application further provides a computer program product including a computer program, and when it is executed by a computer, the method described in the 1st aspect is caused to be executed by the computer.

[0044] In the 15th aspect, the present application further provides a computer program product including a computer program, and when it is executed by a computer, the method described in the 2nd aspect is caused to be executed by the computer.

[0045] In a 16th aspect, the present application provides a chip system including at least one processor and an interface to support a terminal device in realizing a function according to the 1st aspect, for example, determining or processing at least one of data and information according to the above method. In a possible design, the chip system further includes a memory for storing computer programs and data necessary for the terminal device. This chip system may be composed of chips or may include chips and other discrete elements.

[0046] In a 17th aspect, the present application provides a chip system including at least one processor and an interface to support a network-side device in realizing a function according to the 2nd aspect, for example, determining or processing at least one of data and information according to the above method. In a possible design, the chip system further includes a memory for storing computer programs and data necessary for the network-side device. This chip system may be composed of chips or may include chips and other discrete elements.

[0047] In an 18th aspect, the present application provides a computer program which, when executed by a computer, causes the computer to execute the method described in the 1st aspect above.

[0048] In a 19th aspect, the present application provides a computer program which, when executed by a computer, causes the computer to execute the method described in the 2nd aspect above.

Brief Description of Drawings

[0049] To more clearly explain the technical solutions in the embodiments or background art of the present application, the drawings necessary for use in the embodiments or background art of the present application will be described below.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Modes for Carrying Out the Invention

[0050] Hereinafter, embodiments of the present disclosure will be described in detail. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals from beginning to end indicate the same or similar elements, or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are for explaining the present disclosure and should not be construed as limitations on the present disclosure. In the description of the present disclosure, unless otherwise specified, "or" represents the meaning of "either", for example, the description of "A or B" can represent A or B. For example, the "TD basis vector or DD basis vector" in this specification can represent the TD basis vector or the DD basis vector. The "and / or" in this specification is only for explaining the relevant relationship of the relevant object and represents that three relationships are possible. For example, the description of "A and / or B" can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0051] For a terminal device moving at medium to high speed, due to the rapid change of the channel in the time domain, the channel state information (CSI) is still fed back based on the conventional Type II codebook. Since the fed-back CSI does not match the current channel information, the system performance deteriorates. To solve this problem, according to research, by introducing basis vectors in the time domain or Doppler domain based on the Rel-16 or 17 Type II codebook, pre-coding prediction for future times can be realized so that the predicted preset code matches the channel at the corresponding future time. The codebook structure corresponding to the extended CSI feedback based on the Rel-16 or 17 Type II codebook is

Number

Number

[0052] In addition, in a medium / high-speed moving scenario, to introduce a TD basis vector or a DD basis vector for an extended design of the Rel-16 or 17 Type II codebook, first, it is necessary to determine the length N4 of the TD basis vector or the length N4 of the DD basis vector and calculate preset codes corresponding to different times. Therefore, the embodiments of the present application provide a channel state information feedback method and apparatus. By determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector, this length can be used to determine the TD basis vector or the DD basis vector used in the codebook. Thereby, not only can a TD basis vector or a Doppler domain basis vector be introduced based on the Rel-16 or 17 Type II codebook and preset codes corresponding to different times be determined, but also redundant settings of codebook parameters or redundant reporting of codebook parameters can be avoided, and signaling overhead can be reduced.

[0053] To better understand the channel state information feedback method disclosed by the embodiments of this application, first, the communication system applied in the embodiments of this application will be described below.

[0054] Referring to FIG. 1, FIG. 1 is a schematic diagram of the architecture of a communication system provided by an embodiment of this application. The communication system can include one network-side device and one terminal device, but is not limited thereto. The number and form of the devices shown in FIG. 1 are used only for illustration and do not constitute a limitation on the embodiments of this application. In actual applications, it may include two or more network-side devices and two or more terminal devices. Taking the example that the communication system shown in FIG. 1 includes one network-side device 101 and one terminal device 102.

[0055] Note that the technical solution of the embodiments of this application is applicable to various communication systems. For example, a long term evolution (LTE) system, a 5th generation (5G) mobile communication system, a 5G new radio (NR) system, or other future new mobile communication systems, etc.

[0056] The network-side device 101 in the embodiments of this application is a network-side entity for transmitting or receiving signals. For example, the network-side device 101 may be an evolved NodeB (eNB), a transmission reception point (TRP), a next generation NodeB (gNB) in an NR system, a base station in other future mobile communication systems, or an access node in a wireless fidelity (WiFi) system, etc. The embodiments of this application do not limit the specific technologies and specific device forms adopted by the network-side device. The network-side device provided by the embodiments of this application may be composed of a central unit (CU) and a distributed unit (DU). Here, the CU is also called a control unit. By adopting the CU-DU structure, the protocol layer of the network-side device, such as a base station, can be separated, the functions of some protocol layers can be centrally controlled by the CU, the functions of the remaining part or all of the protocol layers can be distributed to the DU, and the DU can be centrally controlled by the CU.

[0057] The terminal device 102 in the embodiments of this application is an entity on the user side for receiving or transmitting signals such as a mobile phone. The terminal device can also be referred to as a terminal, user equipment (UE), mobile station (MS), mobile terminal (MT), etc. The terminal device may be an automobile with a communication function, a smart car, a mobile phone, a wearable device, a tablet (Pad), a personal computer with a wireless transceiver function, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal device for industrial control, a wireless terminal device for self-driving, a wireless terminal device for remote medical surgery, a wireless terminal device for smart grid, a wireless terminal device for transportation safety, a wireless terminal device for smart city, a wireless terminal device for smart home, etc. Also, in the embodiments of the present invention, the terminal device 102 can also include other devices capable of data communication with a network-side device 101 (such as a base station), such as a relay. The embodiments of this application do not limit the specific technologies and specific device forms adopted by the terminal device.

[0058] Note that the communication system described in the embodiments of this application is for more clearly explaining the technical solutions of the embodiments of this application and does not constitute a limitation on the technical solutions provided by the embodiments of this application. Those skilled in the art can understand that as the system architecture evolves and new traffic scenarios emerge, the technical solutions provided by the embodiments of this application can be similarly applied to similar problems.

[0059] Hereinafter, a channel state information feedback method and its apparatus provided by the present disclosure will be described in detail with reference to the drawings.

[0060] Referring to FIG. 2, FIG. 2 is a schematic flowchart of a channel state information feedback method provided by an embodiment of the present application. It should be noted that the channel state information feedback method of the embodiment of the present application can be executed by a terminal device, that is, the channel state information feedback method of the embodiment of the present application is described from the terminal device side. As shown in FIG. 2, this method can include the following steps, but is not limited thereto.

[0061] In step 201, based on the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector and the codebook parameter set by the network-side device, codebook indication information corresponding to the data transmission layer is determined.

[0062] Optionally, the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector can be determined. In one implementation, this length can be determined by the terminal device based on relevant information, or this length can also be set by the network-side device. For example, the terminal device can implicitly determine the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector based on the relevant parameters set by the network-side device. Or, the terminal device determines the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector based on information such as the estimated Doppler offset information and Doppler spread. Or, the terminal device can also receive the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector set by the network-side device.

[0063] In one implementation, the terminal device can receive codebook parameters transmitted from a network-side device (e.g., a base station), and these codebook parameters are set by the network-side device and used to indicate the maximum support parameters for the terminal device to feedback CSI information.

[0064] In a possible implementation, the terminal device receives codebook parameters set by a network-side device (e.g., a base station), and based on this codebook parameter and the length of the TD basis vector, it can determine the codebook indication information corresponding to the data transmission layer. In the embodiments of this application, this codebook indication information can include, but is not limited to, a combination of one or more of a matrix composed of at least one spatial domain (SD) basis vector, a combination coefficient matrix, a matrix composed of at least one frequency domain (FD) basis vector, and a matrix composed of at least one TD basis vector. The length of this TD basis vector is used to determine the TD basis vector used in the codebook, and a time domain basis vector is introduced based on the Rel-16 or 17 Type II codebook. This "at least one" can be understood as one or more, and this "more than one" means at least two, such as two, three, etc., unless there are particularly clear and specific limitations.

[0065] In one possible implementation, the terminal device receives codebook parameter set by a network-side device (e.g., a base station), and based on this codebook parameter and the length of the DD basis vector, can determine codebook indication information corresponding to the data transmission layer. In the embodiments of this application, this codebook indication information can include, but is not limited to, one or a combination of a matrix composed of at least one spatial domain (SD) basis vector, a combination coefficient matrix, a matrix composed of at least one frequency domain (FD) basis vector, and a matrix composed of at least one DD basis vector. The length of this DD basis vector is used to determine the DD basis vector used in the codebook, and the Doppler region basis vector is introduced based on the Rel-16 or 17 Type II codebook.

[0066] In step 202, transmit channel state information (CSI) including codebook indication information to the network-side device, and the codebook indication information is used to instruct the network-side device to determine precoding matrices corresponding to different times.

[0067] Optionally, when the terminal device determines codebook indication information corresponding to the data transmission layer, it can transmit the channel state information (CSI) including this codebook indication information to the network-side device. When the network-side device receives this CSI transmitted from the terminal device, it can determine precoding matrices corresponding to different times based on the codebook indication information in this CSI.

[0068] In one implementation, taking as an example that the codebook indication information can include a matrix composed of a plurality of spatial domain (SD) basis vectors, a combination coefficient matrix, a matrix composed of a plurality of frequency domain (FD) basis vectors, and a matrix composed of a plurality of TD basis vectors, when the network-side device receives the CSI including this codebook indication information, based on this codebook indication information, the codebook structure is

Number

[0069] In one implementation, taking as an example that the codebook indication information can include a matrix composed of a plurality of spatial domain (SD) basis vectors, a combination coefficient matrix, a matrix composed of a plurality of frequency domain (FD) basis vectors, and a matrix composed of a plurality of DD basis vectors, when the network-side device receives the CSI including this codebook indication information, based on this codebook indication information, the codebook structure is

Number

[0070] By implementing the embodiments of this application, the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector can be determined, and this length can be used to determine the TD basis vector or the DD basis vector used in the codebook. Thereby, precoding calculation or prediction for future times can be realized by introducing the time domain basis vector or the Doppler domain basis vector based on the Rel-16 or 17 Type II codebook, so that the calculated or predicted preset code can be matched with the channel at the corresponding future time, and preset codes corresponding to different times can be determined. Moreover, redundant setting of codebook parameters or redundant reporting of codebook parameters can be avoided, and signaling setting overhead or reporting feedback overhead can be reduced.

[0071] It should be noted that the terminal device can implicitly determine the length of the TD basis vector or the length of the DD basis vector based on relevant parameters set by the network-side device. In some embodiments of this application, as shown in FIG. 3, this channel state information feedback method can include the following steps, but is not limited thereto.

[0072] In step 301, based on the first parameter set by the network-side device, determine the length of the TD basis vector or the length of the DD basis vector.

[0073] Optionally, the terminal device can implicitly determine the length of the TD basis vector or the length of the DD basis vector based on the first parameter set by the network-side device.

[0074] In some embodiments of the present application, this first parameter can include, but is not limited to, the number of channel state information reference signal (CSI-RS) resources, the number of CSI-RS resources within the CSI-RS measurement window, the size of the CSI-RS measurement window, the interval between adjacent CSI measurement times, the number of CSI measurements, the number of CSI measurements within the CSI-RS measurement window, the parameter W, etc. Note that the CSI-RS measurement window set by the network-side device is for easily explaining that CSI-RS performs channel measurements one or more times within a certain time range, and it is also possible that the network-side device does not set this CSI-RS measurement window.

[0075] In one implementation form, taking the example that this first parameter is the number of channel state information reference signal (CSI-RS) resources or the number of CSI-RS resources within the CSI-RS measurement window, based on the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window, the length of the TD basis vector or the length of the DD basis vector can be determined.

[0076] In a possible implementation form, it can be determined that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window. For example, the number N of CSI-RS resources set by the network-side device CSI-RSTaking the case where it is 4 as an example, it can be determined that the length of the TD basis vector or the length N4 of the DD basis vector is 4. Also, for example, the number N of CSI-RS resources within the CSI-RS measurement window set by the network-side device CSI-RS Taking the case where it is 6 as an example, it can be determined that the length of the TD basis vector or the length N4 of the DD basis vector is 6.

[0077] In a possible implementation form, it can be determined that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources set by the network-side device. Here, Q1 is a positive integer. For example, when Q1 is 1 and the number N of CSI-RS resources set by the network-side device CSI-RS Taking the case where it is 4 as an example, it can be determined that the length of the TD basis vector or the length N4 of the DD basis vector is 4.

[0078] In a possible implementation form, it can be determined that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources within the CSI-RS measurement window set by the network-side device, where Q1 is a positive integer. For example, when Q1 is 1 and the number N of CSI-RS resources within the CSI-RS measurement window set by the network-side device CSI-RS Taking the case where it is 6 as an example, it can be determined that the length of the TD basis vector or the length N4 of the DD basis vector is 6.

[0079] In a possible implementation form, the length of the TD basis vector or the length of the DD basis vector is

Number

Number

[0080] Note that in the embodiments of the present application, when the number N of the above CSI-RS resources CSI-RS is greater than 1, these N CSI-RS CSI-RS resources may have the same time domain type or different time domain types. The time domain type includes periodic, semi-persistent, and aperiodic. Also, in the embodiments of the present application, when the number N of the above CSI-RS resources CSI-RS is greater than 1, these N CSI-RS CSI-RS resources may be CSI-RS resources with different functions. For example, one CSI-RS is set as a CSI-RS resource for channel acquisition, and the remaining CSI-RS are set as CSI-RS resources for time-frequency tracking.

[0081] In some embodiments of the present application, taking the first parameter being the size of the CSI-RS measurement window and the interval between adjacent CSI measurement times as an example, based on the size of the CSI-RS measurement window and the interval between adjacent CSI measurement times set by the network-side device, the length of the TD basis vector or the length of the DD basis vector can be determined.

[0082] In a possible implementation form, the length of the TD basis vector or the length of the DD basis vector is

Number

[0083] In some embodiments of this application, taking the example that this first parameter is the number of CSI measurements or the number of CSI measurements within the CSI-RS measurement window, based on the number of CSI measurements set by the network-side device or the number of CSI measurements within the CSI-RS measurement window, the length of the TD basis vector or the length of the DD basis vector can be determined.

[0084] In a possible implementation form, it is determined that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI measurements set by the network-side device or the number of CSI measurements within the CSI-RS measurement window. For example, taking the example that the number of CSI measurements B set by the network-side device is 2, the length of the TD basis vector or the length of the DD basis vector N4 is 2. Also, for example, taking the example that the number of CSI measurements B within the CSI-RS measurement window set by the network-side device is 2, the length of the TD basis vector or the length of the DD basis vector N4 is 2.

[0085] In a possible implementation form, it can be determined that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements set by the network-side device, where Q2 is a positive integer.

[0086] In a possible implementation form, it can be determined that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements within the CSI-RS measurement window set by the network-side device, where Q2 is a positive integer.

[0087] In a possible implementation form, the length of the TD basis vector or the length of the DD basis vector is

Number

Number

[0088] In some embodiments of this application, taking this first parameter as the parameter W as an example, based on the parameter W set by the network-side device, the length of the TD basis vector or the length of the DD basis vector can be determined.

[0089] In a possible implementation form, the length of the TD basis vector or the length of the DD basis vector is

Number

[0090] In a possible implementation form, the length of the TD basis vector or the length of the DD basis vector is

Number

Number

Number

Number

Number

[0091] In some embodiments of the present application, this parameter W is 1) the slot corresponding to the CSI reporting time, and 2) the slot where the CSI reference resource is located, and 3) the slot corresponding to the left or right boundary of the CSI-RS measurement window, and 4) the slot corresponding to the left or right boundary of the CSI reporting window, and can be determined by at least one of the parameters. Note that the CSI reporting window is set by the network-side device. Setting the CSI reporting window is for the purpose of easily explaining that the CSI reports the CSI once within a certain time range, and there is also a possibility of not setting the CSI reporting window.

[0092] For example, this parameter W can represent the length W CSI of the CSI reporting window, that is, W = W CSI is. Or, this parameter W can represent the length W meas of the CSI measurement window, that is, W = W measOr, this parameter W represents the time length from the slot corresponding to the first time when the CSI-RS resource is received and CSI measurement is performed to the slot corresponding to the time when the right boundary of the CSI reporting window is located, and the unit of this time length is one slot. Or, this parameter W represents the time length from the slot corresponding to the right boundary or the left boundary of the CSI-RS measurement window to the slot corresponding to the time when the right boundary of the CSI reporting window is located. Or, this parameter W represents the time length from the slot corresponding to the CSI reference resource to the slot corresponding to the time when the right boundary of the CSI reporting window is located.

[0093] Note that in the embodiments of this application, N in the above text CSI-RS , B, d, Q1, Q2, W meas and W meas The values of can be reported by the terminal device, or can be set by the network-side device, or can also be predefined by the terminal device and the network-side device.

[0094] In some embodiments of this application, the terminal device also needs to determine the compression unit C in the time domain. Here, this compression unit C u can be determined by any one of the following methods. u

[0095] In a possible implementation form, this compression unit C u may be αT c , where α is an integer less than or equal to 1, and T c is the channel coherence time. This channel coherence time is

Equation

[0096] In a possible implementation form, this compression unit C u may be the measurement period of the CSI-RS resource.

[0097] In one possible implementation, this compression unit C u may be βd1, where β is an integer greater than or equal to 1 and d1 is the measurement interval of adjacent CSI. For example, for a plurality of uniform CSI measurements, d1 may be the measurement interval of adjacent CSI, and the values of d1 and β can be used to determine this compression unit C u can be determined.

[0098] In one possible implementation, this compression unit C u may be βd2, where β is an integer greater than or equal to 1 and d2 is the maximum or minimum interval of adjacent CSI measurements, or d2 may be the average value of a plurality of adjacent CSI measurement intervals. For example, in the case of a plurality of non-uniform CSI measurements, d2 may be the maximum or minimum interval of adjacent CSI measurements, and the values of d2 and β can be used to determine this compression unit C u can be determined.

[0099] Note that in the embodiments of this application, the values of α and β in the above text can be reported by the terminal device, or can be set by the network-side device, or can be predefined by the terminal device and the network-side device.

[0100] In step 302, based on the codebook parameters and length set by the network-side device, determine the codebook indication information corresponding to the data transmission layer.

[0101] Step 302 can be implemented using any method in the embodiments of this application, and is not limited in the embodiments of this application, and the description is omitted.

[0102] In step 303, transmit the channel state information (CSI) including the codebook indication information to the network-side device, where the codebook indication information is used to instruct the network-side device to determine the precoding matrix corresponding to different times.

[0103] Step 302 can be implemented using any method of each embodiment of the present application, is not limited in the embodiments of the present application, and the description thereof is also omitted.

[0104] By implementing the embodiments of the present application, the length of the TD basis vector or the length of the DD basis vector can be implicitly determined based on the relevant parameters set by the network-side device, and this length can be used to determine the TD basis vector or the DD basis vector used in the codebook. Thereby, a time-domain basis vector or a Doppler-domain basis vector can be introduced into the basis of the Rel-16 or 17 Type II codebook, and pre-coding calculation or prediction at a future time can be realized. Thereby, the calculated or predicted preset code can be matched with the channel at the corresponding future time, and not only can preset codes corresponding to different times be determined, but also redundant setting of codebook parameters or redundant reporting of codebook parameters can be avoided, and signaling setting overhead or reporting feedback overhead can be reduced.

[0105] In some embodiments of the present application, the terminal device can determine the length of the TD basis vector or the length of the DD basis vector based on the estimated Doppler offset information and Doppler spread. For example, the terminal device receives a CSI-RS resource set by the network-side device, uses this CSI-RS resource to perform CSI measurement processing, estimates and obtains the Doppler offset information and Doppler spread, and the terminal device determines the length of the TD basis vector or the length of the DD basis vector based on the estimated Doppler offset information and Doppler spread, and can easily use this length to determine the TD basis vector or the DD basis vector used in the codebook, thereby introducing a time-domain basis vector or a Doppler-domain basis vector based on the Rel-16 or 17 Type II codebook, realizing pre-coding calculation or prediction at a future time, thereby matching the calculated or predicted preset code with the channel at the corresponding future time, not only being able to determine preset codes corresponding to different times, but also avoiding redundant setting of codebook parameters or redundant reporting of codebook parameters, and reducing signaling setting overhead or reporting feedback overhead.

[0106] In some embodiments of the present application, the terminal device can receive the length of the TD basis vector or the length of the DD basis vector set by the network-side device. That is, the length of this TD basis vector or the length of the DD basis vector may be set by the network-side device for the terminal device. The network-side device can implicitly determine the length of this TD basis vector or the length of the DD basis vector based on the related parameters (for example, the first parameter in the above text) set by the network-side device, or the network-side device can determine the length of the TD basis vector or the length of the DD basis vector based on the Doppler offset information and Doppler spread reported from the terminal device. When the network-side device determines the length of the TD basis vector or the length of the DD basis vector of the terminal device, it can send the length of this TD basis vector or the length of the DD basis vector to the terminal device to facilitate the terminal device to determine the TD basis vector or the DD basis vector used in the codebook using this length. Thereby, a time-domain basis vector or a Doppler-domain basis vector can be introduced based on the Rel-16 or 17 Type II codebook, and pre-coding calculation or prediction for future time can be realized. Thereby, the calculated or predicted preset code can be matched with the channel at the corresponding future time, and not only can preset codes corresponding to different times be determined, but also redundant setting of codebook parameters or redundant reporting of codebook parameters can be avoided, and signaling setting overhead or reporting feedback overhead can be reduced.

[0107] Note that the above embodiments are embodiments for explaining the channel state information feedback method according to the embodiments of the present application from the terminal device side. The embodiments of the present application further provide a channel state information feedback method. Hereinafter, an implementation form of this channel state information feedback method will be described from the network side device. Referring to FIG. 4, FIG. 4 is a schematic flowchart of another channel state information feedback method provided by the embodiments of the present application. Note that the channel state information feedback method of the embodiments of the present application can be executed by the network side device. As shown in FIG. 4, this channel state information feedback method can include, but is not limited to, the following steps 401 to 405.

[0108] In step 401, determine the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector.

[0109] Optionally, the network side device can implicitly determine the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector based on related parameters set by the network side device. Alternatively, the network side device can also determine the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector based on information such as Doppler offset information and Doppler spread reported from the terminal device. For example, the terminal device receives a CSI-RS resource set by the network side device, performs CSI measurement processing using this CSI-RS resource, estimates and obtains Doppler offset information and Doppler spread, and the terminal device reports the estimated Doppler offset information and Doppler spread to the network side device, so that the network side device can determine the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector based on information such as Doppler offset information and Doppler spread reported from the terminal device.

[0110] In step 402, codebook parameters are set for the terminal device.

[0111] In step 403, the length of the TD basis vector or the length of the DD basis vector and the codebook parameters are transmitted to the terminal device.

[0112] In one implementation, the network-side device transmits the length of the TD basis vector or the length of the DD basis vector and the codebook parameters to the terminal device, so that the terminal device determines codebook indication information corresponding to the transmission layer based on the length of the TD basis vector or the length of the DD basis vector and the codebook parameter data transmitted from the network-side device.

[0113] In a possible implementation, the terminal device receives the codebook parameters and the length of the TD basis vector set by the network-side device (e.g., a base station), and based on the codebook parameters and the length of the TD basis vector, can determine codebook indication information corresponding to the data transmission layer. In the embodiments of this application, the codebook indication information can include one or a combination of more than one of a matrix composed of at least one spatial domain (SD) basis vector, a combination coefficient matrix, a matrix composed of at least one frequency domain (FD) basis vector, and a matrix composed of at least one TD basis vector, but is not limited thereto. The length of this TD basis vector is used to determine the TD basis vector used in the codebook, and a time domain basis vector is introduced based on the Rel-16 or 17 Type II codebook.

[0114] In one possible implementation, the terminal device receives the codebook parameter and the length of the DD basis vector set by the network-side device (e.g., base station), and can determine the codebook indication information corresponding to the data transmission layer based on the codebook parameter and the length of the DD basis vector. In the embodiments of the present application, this codebook indication information can include, but is not limited to, one or a combination of a matrix composed of at least one spatial domain (SD) basis vector, a combination coefficient matrix, a matrix composed of at least one frequency domain (FD) basis vector, and a matrix composed of at least one DD basis vector. The length of this DD basis vector is used to determine the DD basis vector used in the codebook, and the Doppler domain basis vector is introduced based on the Rel-16 or 17 Type II codebook.

[0115] In step 404, the terminal device receives the codebook indication information corresponding to the data transmission layer determined based on the length and the codebook parameter.

[0116] Optionally, after the terminal device determines the codebook indication information corresponding to the data transmission layer based on the length of the TD basis vector or the length of the DD basis vector and the codebook parameter, the terminal device can send this codebook indication information to the network-side device so that the network-side device can receive this codebook indication information sent from the terminal device.

[0117] In step 405, a precoding matrix corresponding to different times is determined based on the codebook indication information.

[0118] Optionally, based on this codebook indication information, a precoding matrix corresponding to different times can be calculated using the codebook structural formula, or a precoding matrix corresponding to different times can be predicted using a PMI prediction algorithm.

[0119] In one implementation, taking as an example that the codebook indication information can include a matrix composed of a plurality of spatial domain (SD) basis vectors, a combination coefficient matrix, a matrix composed of a plurality of frequency domain (FD) basis vectors, and a matrix composed of a plurality of TD basis vectors, when the network-side device receives the CSI including this codebook indication information, based on this codebook indication information, the codebook structure is

Number

[0120] In one implementation, taking as an example that the codebook indication information can include a matrix composed of a plurality of spatial domain (SD) basis vectors, a combination coefficient matrix, a matrix composed of a plurality of frequency domain (FD) basis vectors, and a matrix composed of a plurality of DD basis vectors, when the network-side device receives the CSI including this codebook indication information, based on this codebook indication information, the codebook structure is

Number

[0121] By implementing the embodiments of the present application, the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector can be determined, and this length can be used to determine the TD basis vector or the DD basis vector used in the codebook. Thereby, a time domain basis vector or a Doppler domain basis vector can be introduced based on the Rel-16 or 17 Type II codebook, and precoding calculation or prediction for future times can be realized. Thereby, the calculated or predicted preset code can be matched with the channel at the corresponding future time, and not only can preset codes corresponding to different times be determined, but also redundant setting of codebook parameters or redundant reporting of codebook parameters can be avoided, and signaling setting overhead or reporting feedback overhead can be reduced.

[0122] It should be noted that the network-side device can implicitly determine the length of the TD basis vector or the length of the DD basis vector based on relevant parameters set by the network-side device. In some embodiments of the present application, as shown in FIG. 5, this channel state information feedback method can include, but is not limited to, the following steps 501 to 505.

[0123] In step 501, based on the first parameter set by the network-side device, determine the length of the TD basis vector or the length of the DD basis vector.

[0124] Optionally, the network-side device can implicitly determine the length of the TD basis vector or the length of the DD basis vector based on the first parameter set by the network-side device.

[0125] In some embodiments of the present application, this first parameter can include, but is not limited to, the number of channel state information reference signal (CSI-RS) resources, the number of CSI-RS resources within the CSI-RS measurement window, the size of the CSI-RS measurement window, the interval between adjacent CSI measurement times, the number of CSI measurements, the number of CSI measurements within the CSI-RS measurement window, parameter W, etc. Note that the CSI-RS measurement window set by the network-side device is for easily explaining that CSI-RS performs channel measurements one or more times within a certain time range, and there is also a possibility that the network-side device does not set this CSI-RS measurement window.

[0126] Taking as an example that this first parameter is the number of channel state information reference signal (CSI-RS) resources or the number of CSI-RS resources within the CSI-RS measurement window in one implementation form, based on the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window, the length of the TD basis vector or the length of the DD basis vector can be determined.

[0127] In a possible implementation form, it can be determined that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window.

[0128] For example, the number N of CSI-RS resources set by the network-side device CSI-RS Taking the example that it is 4, the length of the TD basis vector or the length N4 of the DD basis vector can be determined to be 4. Also, for example, the number N of CSI-RS resources within the CSI-RS measurement window set by the network-side device CSI-RS Taking the example that it is 6, the length of the TD basis vector or the length N4 of the DD basis vector can be determined to be 6.

[0129] In a possible implementation form, the length of the TD basis vector or the length of the DD basis vector can be determined to be equal to Q1 times the number of CSI-RS resources set by the network-side device. Here, Q1 is a positive integer. For example, when Q1 is 1 and the number N of CSI-RS resources set by the network-side device CSI-RS Taking the example that it is 4, the length of the TD basis vector or the length N4 of the DD basis vector can be determined to be 4.

[0130] In a possible implementation form, the length of the TD basis vector or the length of the DD basis vector can be determined to be equal to Q1 times the number of CSI-RS resources within the CSI-RS measurement window set by the network-side device, where Q1 is a positive integer. For example, when Q1 is 1 and the number N of CSI-RS resources within the CSI-RS measurement window set by the network-side device CSI-RS Taking the example that it is 6, the length of the TD basis vector or the length N4 of the DD basis vector can be determined to be 6.

[0131] In a possible implementation form, the length of the TD basis vector or the length of the DD basis vector is

Number

[0132] In the embodiments of the present application, when the number N CSI-RS of the above CSI-RS resources is greater than 1, these N CSI-RS CSI-RS resources may have the same time domain type or different time domain types. The time domain type includes periodic, semi-persistent, and aperiodic. Also, in the embodiments of the present application, when the number N CSI-RS of the above CSI-RS resources is greater than 1, these N CSI-RS CSI-RS resources may be CSI-RS resources with different functions. For example, one CSI-RS is set as a CSI-RS resource for channel acquisition, and the remaining CSI-RS are set as CSI-RS resources for time-frequency tracking.

[0133] In some embodiments of the present application, taking the first parameter as the size of the CSI-RS measurement window and the interval between adjacent CSI measurement times as an example, based on the size of the CSI-RS measurement window set by the network-side device and the interval between adjacent CSI measurement times, the length of the TD basis vector or the length of the DD basis vector can be determined.

[0134] In a possible implementation form, the length of the TD basis vector or the length of the DD basis vector is [Number] can be determined to be equal to, where W meas is the size of the CSI-RS measurement window, d may be the interval between adjacent CSI measurement times, or d may be the maximum or minimum interval between adjacent CSI measurements, or d may be the average value of a plurality of adjacent CSI measurement intervals.

[0135] In some embodiments of the present application, taking the example that this first parameter is the number of CSI measurements or the number of CSI measurements within the CSI-RS measurement window, based on the number of CSI measurements set by the network-side device or the number of CSI measurements within the CSI-RS measurement window, the length of the TD basis vector or the length of the DD basis vector can be determined.

[0136] In a possible implementation form, it is determined that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI measurements set by the network-side device or the number of CSI measurements within the CSI-RS measurement window. For example, taking the example that the number of CSI measurements B set by the network-side device is 2, the length of the TD basis vector or the length of the DD basis vector N4 is 2. Also, for example, taking the example that the number of CSI measurements B within the CSI-RS measurement window set by the network-side device is 2, the length of the TD basis vector or the length of the DD basis vector N4 is 2.

[0137] In a possible implementation form, it can be determined that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements set by the network-side device, where Q2 is a positive integer.

[0138] In a possible implementation form, it can be determined that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements within the CSI-RS measurement window set by the network-side device, where Q2 is a positive integer.

[0139] In a possible implementation form, the length of the TD basis vector or the length of the DD basis vector is

Number

Number

[0140] In some embodiments of this application, taking this first parameter as parameter W for example, based on the parameter W set by the network-side device, the length of the TD basis vector or the length of the DD basis vector can be determined.

[0141] In a possible implementation form, the length of the TD basis vector or the length of the DD basis vector is

Number

[0142] In a possible implementation form, the length of the TD basis vector or the length of the DD basis vector is

Number

Number

Number

Number

Number

[0143] In some embodiments of this application, this parameter W can be determined by at least one parameter among 1) the slot corresponding to the CSI reporting time, 2) the slot where the CSI reference resource is located, 3) the slot corresponding to the left or right boundary of the CSI-RS measurement window, 4) the slot corresponding to the left or right boundary of the CSI reporting window. Note that the CSI reporting window is set by the network-side device. The reason for setting the CSI reporting window is to easily explain that the CSI reports the CSI once within a certain time range. There may also be a possibility of not setting the CSI reporting window.

[0144] For example, this parameter W is the length of the CSI reporting window W CSI That is, W = W CSI Alternatively, this parameter W can be expressed as the length of the CSI measurement window W meas That is, W = W meas Alternatively, the parameter W represents a time length from a slot corresponding to a first time when a CSI-RS resource is received and a CSI measurement is performed to a slot corresponding to a time at which the right boundary of the CSI reporting window is located, and the unit of this time length is one slot. Alternatively, the parameter W represents a time length from a slot corresponding to the right boundary or the left boundary of the CSI-RS measurement window to a slot corresponding to a time at which the right boundary of the CSI reporting window is located. Alternatively, the parameter W represents a time length from a slot corresponding to a CSI reference resource to a slot corresponding to a time at which the right boundary of the CSI reporting window is located.

[0145] In the examples of the present application, CSI-RS , B, d, Q1, Q2, W meas and W meas The value of can be reported by the terminal device, or can be set by the network side device, or can be predefined by the terminal device and the network side device.

[0146] In some embodiments of the present application, the network side device may include a time domain compression unit C u It is also necessary to determine the compression unit C u can be determined in any one of the following ways:

[0147] In one possible implementation, this compression unit C u is αT c where α is an integer less than or equal to 1, and T c is the channel coherence time. This channel coherence time is

number

[0148] In one possible implementation, this compression unit C u may be the measurement period of the CSI-RS resource.

[0149] In one possible implementation, this compression unit C u may be βd1, where β is an integer greater than or equal to 1 and d1 is the measurement interval between adjacent CSI measurements. For example, for a plurality of uniform CSI measurements, d1 may be the measurement interval between adjacent CSI measurements, and the values of d1 and β can be used to determine this compression unit C u can be determined.

[0150] In one possible implementation, this compression unit C u may be βd2, where β is an integer greater than or equal to 1 and d2 is the maximum or minimum interval between adjacent CSI measurements, or d2 may be the average value of a plurality of adjacent CSI measurement intervals. For example, in the case of a plurality of non-uniform CSI measurements, d2 may be the maximum or minimum interval between adjacent CSI measurements, and the values of d2 and β can be used to determine this compression unit C u can be determined.

[0151] For example, assuming that the moving speed of the terminal device (UE) is 27 Km / h and the system carrier frequency of the cell where the UE is located is 4 GHz, the maximum Doppler spread f of this user d = 100 HZ, and the coherent time of the user channel is

Number

[0152] Note that in the embodiments of this application, the values of α and β in the above text can be reported by the terminal device, or can be set by the network-side device, or can be predefined by the terminal device and the network-side device. Also, f in the above text d may be reported by the terminal device to the network-side device.

[0153] In step 502, codebook parameters are set for the terminal device.

[0154] Step 502 can be realized by using any method of each embodiment of this application, and is not limited in the embodiments of this application, and the description is also omitted.

[0155] In step 503, the length of the TD basis vector or the length of the DD basis vector and the codebook parameters are transmitted to the terminal device.

[0156] Step 503 can be realized by using any method of each embodiment of this application, and is not limited in the embodiments of this application, and the description is also omitted.

[0157] In step 504, codebook indication information corresponding to the data transmission layer determined based on the length and the codebook parameters is received by the terminal device.

[0158] Step 504 can be implemented using any method of each embodiment of the present application, and is not limited in the embodiments of the present application, so the description thereof is omitted.

[0159] In step 505, a precoding matrix corresponding to different times is determined based on the codebook indication information.

[0160] In one implementation form, based on the codebook indication information and the determination method of the length of the TD basis vector or the length of the DD basis vector, a precoding matrix corresponding to different times can be determined using a codebook structure or a precoding matrix indicator (PMI) prediction algorithm. That is, according to the difference in the determination method of the length of the TD basis vector or the length of the DD basis vector N4, this precoding matrix is obtained in different ways. For example, the prediction of the precoding matrix is performed using a prediction algorithm, or the precoding matrix is calculated using the codebook structure.

[0161] For example, assume that a network-side device (such as a base station) sets an aperiodic CSI-RS resource set including four aperiodic CSI-RS resources for a terminal device (UE). These four aperiodic CSI-RS resources measure the downlink channel information at four different times within one CSI-RS measurement window, and the interval between adjacent CSI-RS resources is d. As shown in FIG. 6, it is the relationship in the time domain between the measurement based on CSI-RS and the CSI report. The measurement time of the first CSI-RS resource is t0, and the measurement time of the last CSI-RS resource is t0 + 3. The UE is based on the downlink channels measured by these four different-time CSI-RS resources and based on the codebook parameters set by the base station, and includes W1 composed of a plurality of SD basis vectors in the codebook, combination coefficient W2, and W f composed of a plurality of FD basis vectors t and W dCalculate, and the UE reports this parameter information to the base station at time t0 + n, and the base station

Number

Number

Number

[0162] For example, when the length N4 of the TD or DD basis vector is

Number

[0163] Also, for example, the length N4 of the TD or DD basis vector is equal to Q times that of B, or the length N4 of the TD or DD basis vector is equal to Q times that of B or C u where B = 4, Q = 5, and C u = 1, that is, N4 = 20. A matrix composed of V or more TD or DD basis vectors is

Number

Number

[0164] The precoding matrix corresponding to N4 time instants can be obtained by calculating

Number

Number

[0165] For the calculation of the precoding matrix at N5 time instants after N4 time instants, that is, for the precoding matrix corresponding to N5 > N4 time instants, it can be calculated by the following formula: First

Number

Number

Number

Number

[0166] As described above, the present application determines the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector, and uses this length to determine the TD basis vector or the DD basis vector used in the codebook. Thereby, a time domain basis vector or a Doppler domain basis vector is introduced based on the Rel-16 or 17 Type II codebook, enabling precoding calculation or prediction for future times. The calculated or predicted preset code can be matched with the channel at the corresponding future time, and preset codes corresponding to different times can be determined. In addition, redundant settings of codebook parameters or redundant reporting of codebook parameters can be avoided, and signaling setting overhead or reporting feedback overhead can be reduced.

[0167] In the embodiments provided by the present application described above, the methods provided by the embodiments of the present application are described from the perspectives of the terminal device and the network-side device, respectively. To implement each function in the method provided by the embodiments of the present application described above, the terminal device and the network-side device can include a hardware configuration and a software module, and can implement each of the above functions in the form of a hardware configuration, a software module, or a hardware configuration plus a software module. Some of the above functions can be executed in the form of a hardware configuration, a software module, or a hardware configuration plus a software module.

[0168] Referring to FIG. 7, FIG. 7 is a schematic configuration diagram of a communication device 70 provided by an embodiment of the present application. The communication device 70 shown in FIG. 7 can include a transceiver module 701 and a processing module 702. The transceiver module 701 can include a transmission module and / or a reception module. The transmission module is used to realize the transmission function, the reception module is used to realize the reception function, and the transceiver module 701 can realize the transmission function and / or the reception function.

[0169] The communication device 70 may be a terminal device, or a device within the terminal device, or a device that can be used in matching with the terminal device. Alternatively, the communication device 70 may be a network-side device, or a device within the network-side device, or a device that can be used in matching with the network device.

[0170] When the communication device 70 is a terminal device, the processing module 702 determines codebook indication information corresponding to the data transmission layer based on the length of the time-domain (TD) basis vector or the length of the Doppler-domain (DD) basis vector and the codebook parameter set by the network-side device. The transceiver module 701 transmits channel state information (CSI) including the codebook indication information to the network-side device. The codebook indication information is used to instruct the network-side device to determine a precoding matrix corresponding to different times.

[0171] In one implementation form, specifically, the processing module 702 determines the length of the time-domain (TD) basis vector or the length of the Doppler-domain (DD) basis vector, and determines codebook indication information corresponding to the data transmission layer based on this length and the codebook parameter set by the network-side device.

[0172] In one implementation, specifically, the processing module 702 determines the length of the TD basis vector or the length of the DD basis vector based on the first parameter set by the network-side device.

[0173] In a possible implementation, the first parameter is the number of channel state information reference signal (CSI-RS) resources or the number of CSI-RS resources within the CSI-RS measurement window. Specifically, the processing module 702 determines that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources within the CSI-RS measurement window set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is

Number

[0174] In a possible implementation, the first parameter is the size of the CSI-RS measurement window and the interval between adjacent CSI measurement times. Specifically, the processing module 702 determines that the length of the TD basis vector or the length of the DD basis vector is

Number

[0175] In a possible implementation, the first parameter is the number of CSI measurements or the number of CSI measurements within the CSI-RS measurement window, and specifically, the processing module 702 determines that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI measurements or the number of CSI measurements within the CSI-RS measurement window set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements within the CSI-RS measurement window set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is

Number

[0176] In a possible implementation, the first parameter is parameter W, and specifically, the processing module 702 determines that the length of the TD basis vector or the length of the DD basis vector is

Number

Number

Number

Number

[0177] In a possible implementation form, the processing module 702 further determines a compression unit C in the time domain u to determine.

[0178] In a possible implementation form, the compression unit C u is αT c where α is an integer less than or equal to 1, and T c is the channel coherence time, or the compression unit C u is the measurement period of the CSI-RS resource, or the compression unit C u is βd1, β is an integer greater than or equal to 1, and d1 is the measurement interval between adjacent CSIs, or the compression unit C u is βd2, β is an integer greater than or equal to 1, and d2 is the maximum interval or minimum interval between adjacent CSI measurements, or the average value of multiple adjacent CSI measurement intervals.

[0179] In a possible implementation form, the processing module 702 specifically determines the length of the TD basis vector or the length of the DD basis vector based on the Doppler offset information and Doppler spread estimated by the terminal device using CSI-RS.

[0180] In a possible implementation form, the transceiver module 701 further receives the length of the TD basis vector or the length of the DD basis vector set by the network-side device.

[0181] In one possible implementation, the codebook indication information includes at least one combination of one or more of a matrix composed of at least one spatial domain (SD) basis vector, a combination coefficient matrix, a matrix composed of at least one frequency domain (FD) basis vector, and a matrix composed of at least one time domain (TD) basis vector or Doppler domain (DD) basis vector.

[0182] When the communication device 70 is a network-side device, the processing module 702 determines the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector. The processing module 702 further sets the codebook parameters for the terminal device. The transceiver module 701 transmits the length of the TD basis vector or the length of the DD basis vector and the codebook parameters to the terminal device. The transceiver module 701 further receives the codebook indication information corresponding to the data transmission layer determined by the length and the codebook parameters from the terminal device. The processing module 702 further determines the precoding matrix corresponding to different times based on the codebook indication information.

[0183] In one implementation, specifically, the processing module 702 determines the length of the TD basis vector or the length of the DD basis vector based on the first parameter set by the network-side device.

[0184] In one possible implementation, the first parameter is the number of channel state information reference signal (CSI-RS) resources or the number of CSI-RS resources within the CSI-RS measurement window, and specifically, the processing module 702 determines that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources within the CSI-RS measurement window set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is

Number

[0185] In one possible implementation, the first parameter is the size of the CSI-RS measurement window and the interval between adjacent CSI measurement times, and specifically, the processing module 702 determines that the length of the TD basis vector or the length of the DD basis vector is

Number

[0186] In a possible implementation form, the first parameter is the number of CSI measurements or the number of CSI measurements within the CSI-RS measurement window, and specifically, the processing module 702 determines that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI measurements or the number of CSI measurements within the CSI-RS measurement window set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements within the CSI-RS measurement window set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is

Number

[0187] In a possible implementation form, the first parameter is parameter W, and specifically, the processing module 702 determines that the length of the TD basis vector or the length of the DD basis vector is

Number

Number

Number

Number

[0188] In a possible implementation form, the processing module 702 further determines a time-domain compression unit C u thereof.

[0189] In a possible implementation form, the compression unit C u is αT c where α is an integer less than or equal to 1, and T c is the channel coherence time, or the compression unit C u is the measurement period of the CSI-RS resource, or the compression unit C u is βd1, where β is an integer greater than or equal to 1, and d1 is the measurement interval between adjacent CSIs, or the compression unit C u is βd2, where β is an integer greater than or equal to 1, and d2 is the maximum interval or the minimum interval between adjacent CSI measurements, or the average value of multiple adjacent CSI measurement intervals.

[0190] In one implementation form, specifically, the processing module 702 determines the length of the TD basis vector or the length of the DD basis vector based on the Doppler offset information and the Doppler spread reported from the terminal device.

[0191] In a possible implementation form, specifically, the processing module 702 determines the precoding matrix corresponding to different times by using a codebook structure or a precoding matrix indicator (PMI) prediction algorithm based on the codebook indication information and the determination method of the length of the TD basis vector or the length of the DD basis vector.

[0192] Regarding the device in the above embodiments, the specific manner in which each module executes operations has already been described in detail in the embodiments related to the method, and thus will not be described in detail here.

[0193] Referring to FIG. 8, FIG. 8 is a schematic configuration diagram of another communication device 80 provided according to an embodiment of the present application. The communication device 80 may be a network device, a terminal device, a chip, a chip system, or a processor that assists the network-side device in implementing the above method, or a chip, a chip system, or a processor that assists the terminal device in implementing the above method. This device can be used to implement the method described in the embodiments of the above method. Specifically, reference can be made to the description of the embodiments of the above method.

[0194] The communication device 80 may include one or more processors 801. The processor 801 may be a general-purpose processor or a dedicated processor, etc. For example, it may be a baseband processor or a central processor. The baseband processor can be used to process communication protocols and communication data, and the central processing unit can control a communication device (such as a base station, a baseband chip, a terminal device, a terminal device chip, a DU or a CU, etc.), execute a computer program, and process the data of the computer program.

[0195] Optionally, the communication device 80 may further include one or more memories 802 capable of storing a computer program 804. The processor 801 executes the computer program 804 so that the communication device 80 executes the method described in the embodiments of the above method. Optionally, data can be further stored in the memory 802. The communication device 80 and the memory 802 may be provided separately or integrated.

[0196] Optionally, the communication device 80 may further include a transceiver 805 and an antenna 806. The transceiver 805 can be referred to as a transceiver unit, a transceiver, or a transceiver circuit, etc. for realizing the transceiver function. The transceiver 805 can include a receiver and a transmitter. The receiver can be referred to as a receiver or a receiving circuit, etc. for realizing the receiving function, and the transmitter can be referred to as a transmitter or a transmitting circuit, etc. for realizing the transmitting function.

[0197] Optionally, the communication device 80 may further include one or more interface circuits 807. The interface circuit 807 is used to receive code instructions and transmit them to the processor 801. The processor 801 executes the code instructions to cause the communication device 80 to execute the methods described in the embodiments of the above method.

[0198] When the communication device 80 is a terminal device, the processor 801 executes step 201 in FIG. 2 and executes steps 301 and 302 in FIG. 3. The transceiver 805 executes step 202 in FIG. 2 and executes step 303 in FIG. 3.

[0199] When the communication device 80 is a network-side device, the transceiver 805 executes steps 401, 402, and 405 in FIG. 4 and executes steps 501, 502, and 505 in FIG. 5. The processor 801 executes steps 403 and 404 in FIG. 4 and executes steps 503 and 504 in FIG. 5.

[0200] In one embodiment, the processor 801 may include a transceiver for realizing reception and transmission functions. For example, this transceiver may be a transceiver circuit, or may be an interface, or may be an interface circuit. The transceiver circuit, interface or interface circuit for realizing reception and transmission functions may be separate or integrated. The transceiver circuit, interface or interface circuit may be used for reading and writing code or data, or the transceiver circuit, interface or interface circuit may be used for signal transmission or transfer.

[0201] In one implementation, when a computer program is executed on the processor 801, the processor 801 can store a computer program that causes the communication device 80 to execute the method described in the embodiments of the above method. The computer program may be hardened in the processor 801, in which case the processor 801 may be realized by hardware.

[0202] In one implementation form, the communication device 80 can include a circuit capable of realizing the functions of transmission, reception, or communication in the embodiments of the above method. The processor and transceiver described in this application can be realized in an integrated circuit (IC), an analog IC, a radio frequency integrated circuit (RFIC), a hybrid signal IC, an application specific integrated circuit (ASIC), a printed circuit board (PCB), an electronic device, etc. This processor and transceiver can be manufactured using various IC process technologies such as complementary metal oxide semiconductor (CMOS), N-type metal oxide semiconductor (NMOS), P-type metal oxide semiconductor (PMOS), bipolar junction transistor (BJT), bipolar CMOS (BiCMOS), silicon germanium (SiGe), gallium arsenide (GaAs).

[0203] The communication device described in the above embodiments may be a network-side device or a terminal device, but the scope of the communication device described in this application is not limited thereto, and the structure of the communication device may not be limited to that shown in FIG. 8. The communication device may be an independent device or a part of a large device. For example, the communication device may be as follows: (1) An independent integrated circuit (IC), or a chip, or a chip system or subsystem, (2) Having a set of one or more ICs, and optionally, this IC set can include a storage component for storing data and computer programs, (3) An ASIC such as a modem, (4) A module that can be incorporated into other devices, (5) Receiver, terminal device, smart terminal device, mobile phone, wireless device, handheld, mobile unit, in-vehicle device, network-side device, cloud device, artificial intelligence device, etc. (6) And others.

[0204] When the communication device may be a chip or a chip system, the schematic configuration diagram of the chip shown in FIG. 9 can be referred to. The chip shown in FIG. 9 includes a processor 901 and an interface 902. Here, the number of processors 901 may be one or more, and the number of interfaces 902 may be more than one.

[0205] When the chip is used to implement the functions of the terminal device in the embodiments of the present application: The processor 901 determines the codebook indication information corresponding to the data transmission layer based on the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector and the codebook parameter set by the network-side device, and the interface 902 transmits the channel state information (CSI) including the codebook indication information to the network-side device. The codebook indication information is used to instruct the network-side device to determine the precoding matrix corresponding to different times.

[0206] In one implementation form, the processor 901 specifically determines the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector, and determines the codebook indication information corresponding to the data transmission layer based on this length and the codebook parameter set by the network-side device.

[0207] In one implementation form, the processor 901 specifically determines the length of the TD basis vector or the length of the DD basis vector based on the first parameter set by the network-side device.

[0208] In one possible implementation, the first parameter is the number of channel state information reference signal (CSI-RS) resources or the number of CSI-RS resources within the CSI-RS measurement window, and specifically, the processor 901 determines that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources within the CSI-RS measurement window set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is

Number

[0209] In one possible implementation, the first parameter is the size of the CSI-RS measurement window and the interval between adjacent CSI measurement times, and specifically, the processor 901

Number

[0210] In a possible implementation form, the first parameter is the number of CSI measurements or the number of CSI measurements within the CSI-RS measurement window, and specifically, the processor 901 determines that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI measurements set by the network-side device or the number of CSI measurements within the CSI-RS measurement window, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements within the CSI-RS measurement window set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is

Number

[0211] In a possible implementation form, the first parameter is parameter W, and specifically, the processor 901 determines that the length of the TD basis vector or the length of the DD basis vector is

Number

Number

Number

Number

[0212] In one possible implementation, the processor 901 further determines a time-domain compression unit C u .

[0213] In one possible implementation, the compression unit C u is αT c , where α is an integer less than or equal to 1, and T c is the channel coherence time, or the compression unit C u is the measurement period of the CSI-RS resource, or the compression unit C u is βd1, where β is an integer greater than or equal to 1, and d1 is the measurement interval between adjacent CSIs, or the compression unit C u is βd2, where β is an integer greater than or equal to 1, and d2 is the maximum or minimum interval between adjacent CSI measurements, or d2 may be the average value of multiple adjacent CSI measurement intervals.

[0214] In one possible implementation, the processor 901 specifically determines the length of the TD basis vector or the length of the DD basis vector based on the Doppler offset information and Doppler spread estimated by the terminal device using CSI-RS.

[0215] In one possible implementation, the interface 902 further receives the length of the TD basis vector or the length of the DD basis vector set by the network-side device.

[0216] In one possible implementation, the codebook indication information includes at least one combination of one or more of a matrix composed of at least one spatial domain (SD) basis vector, a combination coefficient matrix, a matrix composed of at least one frequency domain (FD) basis vector, and a matrix composed of at least one TD basis vector or DD basis vector.

[0217] When the chip is used to implement the functions of the network-side device in the embodiments of the present application: The processor 901 determines the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector, and the processor 901 further sets codebook parameters for the terminal device. The interface 902 transmits the length of the TD basis vector or the length of the DD basis vector and the codebook parameters to the terminal device. The interface 902 further receives codebook indication information corresponding to the data transmission layer determined by the length and the codebook parameters from the terminal device. The processor 901 further determines precoding matrices corresponding to different times based on the codebook indication information.

[0218] In one implementation form, the processor 901 specifically determines the length of the TD basis vector or the length of the DD basis vector based on a first parameter set by the network-side device.

[0219] In a possible implementation form, the first parameter is the number of channel state information reference signal (CSI-RS) resources or the number of CSI-RS resources within the CSI-RS measurement window. The processor 901 specifically determines that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q1 times the number of CSI-RS resources within the CSI-RS measurement window set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is

Number

[0220] In a possible implementation form, the first parameter is the size of the CSI-RS measurement window and the interval between adjacent CSI measurement times. Specifically, the processor 901 determines that the length of the TD basis vector or the length of the DD basis vector is

Number

[0221] In a possible implementation form, the first parameter is the number of CSI measurements or the number of CSI measurements within the CSI-RS measurement window. Specifically, the processor 901 determines that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI measurements set by the network-side device or the number of CSI measurements within the CSI-RS measurement window, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is equal to Q2 times the number of CSI measurements within the CSI-RS measurement window set by the network-side device, or determines that the length of the TD basis vector or the length of the DD basis vector is

Number

[0222] In a possible implementation form, the first parameter is parameter W, and specifically, the processor 901 determines that the length of the TD basis vector or the length of the DD basis vector is [Number] equal to, and W mod C u = 0, and C u is the compression unit in the time domain, or the length of the TD basis vector or the length of the DD basis vector is [Number] or [Number] determined to be equal to, [Number]

[0223] In a possible implementation form, the processor 901 further determines the compression unit C u in the time domain.

[0224] In a possible implementation form, the compression unit C u is αT c , where α is an integer less than or equal to 1, and T c is the channel coherence time, or the compression unit C u is the measurement period of the CSI-RS resource, or the compression unit C u is βd1, where β is an integer greater than or equal to 1, and d1 is the measurement interval between adjacent CSIs, or the compression unit C u is βd2, where β is an integer greater than or equal to 1, and d2 is the maximum interval or minimum interval between adjacent CSI measurements, or d2 may be the average value of multiple adjacent CSI measurement intervals.

[0225] In one implementation, specifically, the processor 901 determines the length of the TD basis vector or the length of the DD basis vector based on the Doppler offset information and the Doppler spread reported from the terminal device.

[0226] In a possible implementation, specifically, the processor 901 determines the precoding matrix corresponding to different times by using a codebook structure or a precoding matrix indicator (PMI) prediction algorithm based on the codebook indication information and the determination method of the length of the TD basis vector or the length of the DD basis vector.

[0227] Optionally, the chip further includes a memory 903 for storing the necessary computer programs and data.

[0228] Those skilled in the art can also understand that the various illustrative logical blocks and steps described in the embodiments of this application can be implemented by electronic hardware, computer software, or a combination of both. Whether to implement such functions in hardware or software is determined by specific applications and the overall design requirements of the system. Those skilled in the art can use various methods to implement the functions described, but this implementation should not be understood as exceeding the protection scope of the embodiments of this application.

[0229] The embodiments of this application further provide a communication system including a communication device serving as the terminal device and a communication device serving as the network-side device in the embodiment of FIG. 7, or a communication device serving as the terminal device and a communication device serving as the network-side device in the embodiment of FIG. 8.

[0230] This application further provides a readable storage medium storing instructions for implementing the functions of the embodiments of any of the above methods when executed by a computer.

[0231] When executed by a computer, the present application further provides a computer program product that realizes the functions of the embodiments of any of the above methods.

[0232] In the above embodiments, it can be realized in whole or in part by software, hardware, firmware, or any combination thereof. When realized using software, it can be realized in whole or in part in the form of a computer program product. The computer program product includes one or more computer programs. The processes or functions according to the embodiments of the present application are generated in whole or in part when the computer loads and executes the computer program. The computer may be a general-purpose computer, a dedicated computer, a computer network, or other programmable devices. The computer program can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer program can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wire (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 accessible by the computer, or may include a data storage device such as a server or data center integrated by one or more available media. The available medium may be a magnetic medium (such as a floppy disk, hard disk, magnetic tape), an optical medium (such as a digital video disc (DVD)), or a semiconductor medium (such as a solid state disk (SSD)), etc.

[0233] A person skilled in the art can understand that the various numerical numbers such as the first, second, etc. related to this application are only for the convenience of explanation, do not limit the scope of the embodiments of this application, and do not indicate the priority order.

[0234] At least one of this application can also be described as one or more, and the plurality can be two, three, four or more, and is not limited to this application. In the embodiments of this application, for one technical feature, the technical features in this type of technical feature are distinguished by "first", "second", "third", "A", "B", "C", and "D", etc., and there is no sequential or size order between the technical features described in the "first", "second", "third", "A", "B", "C", and "D".

[0235] The correspondence shown in each table in this application may be set or predefined. The values of the information in each table are merely examples and can be set as other values, and are not limited to this application. When setting the correspondence between information and each parameter, it is not necessarily required to set all the correspondences shown in each table. For example, in the table of this application, the correspondence shown by a certain row may not be set. As another example, appropriate deformation adjustments such as splitting and merging can be performed based on the above table. The names of the parameters shown in the titles of the above tables can also adopt other names that can be understood by the communication device, and the values or display methods of the parameters can also adopt other values or display methods that can be understood by the communication device. When the above tables are realized, other data structures can also be adopted. For example, arrays, queues, containers, stacks, linear tables, pointers, link tables, trees, graphs, structures, classes, heaps, hash lists, or hash tables, etc. can be adopted.

[0236] The predefined in this application can be understood as definition, predefined, memory, pre-memory, pre-negotiation, pre-setting, hardening, or pre-firing.

[0237] A person skilled in the art can recognize that, in combination with the units and algorithm steps of each example described in the embodiments disclosed in this specification, they can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether a certain function is executed in a hardware or software manner is determined by the specific application of the technical solution and the design constraints. A person skilled in the art can use different methods to implement the functions described for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0238] As is clearly understood by a person skilled in the art, for the sake of convenience and brevity of description, the specific operation processes of the systems, devices and units described above can refer to the corresponding processes in the embodiments of the above method, and the description is omitted here.

[0239] As described above, this is only a specific embodiment of this application, but the protection scope of this application is not limited thereto. A person skilled in the art can easily conceive that within the technical scope disclosed by this application, changes or substitutions should be included within the protection scope of this application. Therefore, the protection scope of this application should be based on the protection scope of the claims.

Claims

1. A method for channel state information feedback executed by a terminal device, comprising: determining codebook indication information corresponding to a data transmission layer based on the length of a time domain (TD) basis vector or the length of a Doppler domain (DD) basis vector and codebook parameters set by a network-side device; transmitting channel state information (CSI) including the codebook indication information to the network-side device, wherein the codebook indication information is used to instruct the network-side device to determine a precoding matrix corresponding to different times. A channel state information feedback method characterized by the above.

2. The step of determining codebook indication information corresponding to a data transmission layer based on the length of a time domain (TD) basis vector or the length of a Doppler domain (DD) basis vector and codebook parameters set by a network-side device comprises: determining the length of a time domain (TD) basis vector or the length of a Doppler domain (DD) basis vector; determining codebook indication information corresponding to a data transmission layer based on the length and the codebook parameters set by the network-side device. The channel state information feedback method according to claim 1, characterized by the above.

3. The step of determining the length of a time domain (TD) basis vector or the length of a Doppler domain (DD) basis vector comprises: determining the length of a TD basis vector or the length of a DD basis vector based on a first parameter set by the network-side device. The channel state information feedback method according to claim 2, characterized by the above.

4. The first parameter is the number of channel state information reference signal (CSI-RS) resources or the number of CSI-RS resources within a CSI-RS measurement window. The step of determining the length of a time domain (TD) basis vector or the length of a Doppler domain (DD) basis vector based on a first parameter set by the network-side device is: Determining that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window; or determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI-RS resources set by the network-side device １ times; Alternatively, determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI-RS resources within the CSI-RS measurement window set by the network-side device １ times; or, the length of the TD basis vector or the length of the DD basis vector is 【Number 1】 A step of determining to be equal to said Q １ where Q is a positive integer and N ＣＳＩ－ＲＳ is the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within a CSI-RS measurement window, and C ｕ is a compression unit in the time domain, including the step of The channel state information feedback method according to claim 3, characterized in that.

5. The first parameter is the size of the CSI-RS measurement window and the interval between adjacent CSI measurement times, Based on the first parameter set by the network-side device, the step of determining the length of the TD basis vector or the length of the DD basis vector is The length of the TD basis vector or the length of the DD basis vector is 【Number 2】 a step of determining to be equal to the said W ｍｅａｓ wherein W is the size of the CSI-RS measurement window, d is the interval between adjacent CSI measurement times, or the maximum or minimum interval between adjacent CSI measurements, or the average value of a plurality of adjacent CSI measurement intervals The channel state information feedback method according to claim 3, characterized in that.

6. The first parameter is the number of CSI measurements or the number of CSI measurements within the CSI-RS measurement window, Based on the first parameter set by the network-side device, the step of determining the length of the TD basis vector or the length of the DD basis vector is Determining that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI measurements set by the network-side device or the number of CSI measurements within the CSI-RS measurement window; Or, determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI measurements set by the network-side device ２ times; or determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI measurements within a CSI-RS measurement window set by the network-side device ２ times; or, the length of the TD basis vector or the length of the DD basis vector is [Number 3] A step of determining to be equal to the said Q ２ wherein Q is a positive integer, B is the number of CSI measurements set by the network-side device or the number of CSI measurements within the CSI-RS measurement window, and C ｕ is a compression unit in the time domain, comprising The channel state information feedback method according to claim 3, characterized in that.

7. The first parameter is parameter W, Based on the first parameter set by the network-side device, the step of determining the length of the TD basis vector or the length of the DD basis vector is The length of the TD basis vector or the length of the DD basis vector is 【Number 4】 a step of determining to be equal to, where W mod C ｕ = 0, and the C ｕ is a compression unit in the time domain or, the length of the TD basis vector or the length of the DD basis vector is 【Number 5】 or 【Number 6】 The step of determining to be equal to, wherein 【Number 7】 The parameter W is 1) The slot corresponding to the CSI reporting time, 2) The slot where the CSI reference resource is located, 3) The slot corresponding to the left or right boundary of the CSI-RS measurement window, 4) Determined by at least one parameter among the slots corresponding to the left or right boundary of the CSI reporting window. The channel state information feedback method according to claim 3, characterized in that...

8. The method includes: The compression unit C in the time domain ｕ further includes a step of determining The channel state information feedback method according to any one of claims 4 to 7, characterized in that...

9. The compression unit C ｕ is αT ｃ where α is an integer of 1 or less, and T ｃ is the channel coherence time, or Or, the compression unit C ｕ is the measurement period of CSI-RS resources, or or the compression unit C ｕ is βd １ where β is an integer of 1 or more, and d １ is the measurement interval of adjacent CSIs, or Or, the compression unit C ｕ is βd ２ where β is an integer of 1 or more, and d ２ is the maximum interval or minimum interval between adjacent CSI measurements, or the average value of a plurality of adjacent CSI measurement intervals The channel state information feedback method according to claim 8, characterized in that...

10. The step of determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector: includes the step of determining the length of the TD basis vector or the length of the DD basis vector based on the Doppler offset information estimated by the terminal device using CSI-RS and the Doppler spread. The channel state information feedback method according to claim 2, characterized in that...

11. The step of determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector: includes the step of receiving the length of the TD basis vector or the length of the DD basis vector set by the network side device. The channel state information feedback method according to claim 2, characterized in that...

12. The codebook indication information includes at least one combination of one or more of a matrix composed of at least one spatial domain (SD) basis vector, a combination coefficient matrix, a matrix composed of at least one frequency domain (FD) basis vector, and a matrix composed of at least one TD basis vector or DD basis vector. The channel state information feedback method according to any one of claims 1 to 11, characterized in that...

13. A channel state information feedback method executed by a network side device, comprising: a step of determining the length of a time domain (TD) basis vector or the length of a Doppler domain (DD) basis vector; a step of setting codebook parameters for a terminal device; a step of transmitting the length of the TD basis vector or the length of the DD basis vector and the codebook parameters to the terminal device; a step of receiving, from the terminal device, codebook indication information corresponding to a data transmission layer determined by the length and the codebook parameters; a step of determining a precoding matrix corresponding to different times based on the codebook indication information. A channel state information feedback method characterized by the following.

14. The step of determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector includes the step of determining the length of the TD basis vector or the length of the DD basis vector based on a first parameter set by the network-side device. The channel state information feedback method according to claim 13, characterized by the above.

15. The first parameter is the number of channel state information reference signal (CSI-RS) resources or the number of CSI-RS resources within the CSI-RS measurement window. The step of determining the length of the TD basis vector or the length of the DD basis vector based on a first parameter set by the network-side device is the step of determining that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window. or determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI-RS resources set by the network-side device １ times; Or, determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI-RS resources within a CSI-RS measurement window set by the network-side device １ times; Or, the length of the TD basis vector or the length of the DD basis vector is 【Number 8】 A step of determining to be equal to the said Q, wherein the said Q １ is a positive integer, and the said N ＣＳＩ－ＲＳ is the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window, and the said C ｕ is a compression unit in the time domain, including the step of The channel state information feedback method according to claim 14, characterized by the above.

16. The first parameter is the size of the CSI-RS measurement window and the interval between adjacent CSI measurement times. The step of determining the length of the TD basis vector or the length of the DD basis vector based on a first parameter set by the network-side device is that the length of the TD basis vector or the length of the DD basis vector is 【Number 9】 A step of determining to be equal to said W ｍｅａｓ where W is the size of the CSI-RS measurement window, d is the interval between adjacent CSI measurement times, or the maximum or minimum interval between adjacent CSI measurements, or the average value of a plurality of adjacent CSI measurement intervals, and the method includes a step of The channel state information feedback method according to claim 14, characterized by the above.

17. The first parameter is the number of CSI measurements or the number of CSI measurements within the CSI-RS measurement window. The step of determining the length of the TD basis vector or the length of the DD basis vector based on a first parameter set by the network-side device is the step of determining that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI measurements set by the network-side device or the number of CSI measurements within the CSI-RS measurement window. Or, determining that the length of the TD base vector or the length of the DD base vector is equal to Q times the number of CSI measurements set by the network-side device ２ times; Alternatively, determining that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI measurements within the CSI-RS measurement window set by the network-side device ２ times; Or, the length of the TD basis vector or the length of the DD basis vector is 【Number 10】 A step of determining to be equal to the said Q ２ wherein Q is a positive integer, B is the number of CSI measurements set by the network-side device or the number of CSI measurements within the CSI-RS measurement window, and C ｕ is a compression unit in the time domain, and the method includes a step of The channel state information feedback method according to claim 14, characterized by the above.

18. The first parameter is parameter W, and the step of determining the length of the TD basis vector or the length of the DD basis vector based on the first parameter set by the network-side device includes: the length of the TD basis vector or the length of the DD basis vector is 【Number 11】 a step of determining to be equal to, where W mod C ｕ = 0, and the C ｕ is a compression unit in the time domain or, the length of the TD basis vector or the length of the DD basis vector is 【Number 12】 or 【Number 13】 determined to be equal to, 【Number 14】 wherein the parameter W is 1) the slot corresponding to the CSI reporting time, 2) the slot where the CSI reference resource is located, 3) the slot corresponding to the left or right boundary of the CSI-RS measurement window, 4) determined by at least one parameter among the slots corresponding to the left or right boundary of the CSI reporting window, The channel state information feedback method according to claim 14, characterized in that.

19. The method is The compression unit C in the time domain ｕ further includes a step of determining The channel state information feedback method according to any one of claims 15 to 18, characterized in that.

20. the compression unit C ｕ is αT ｃ where α is an integer of 1 or less, and T ｃ is the channel coherence time, or Or, the compression unit C ｕ is the measurement period of the CSI-RS resource, or or the compression unit C ｕ is βd １ where β is an integer of 1 or more, and d １ is the measurement interval of adjacent CSIs, or or the compression unit C ｕ is βd ２ where β is an integer of 1 or more, and d ２ is the maximum interval or minimum interval between adjacent CSI measurements, or the average value of a plurality of adjacent CSI measurement intervals The channel state information feedback method according to claim 19, characterized in that.

21. The step of determining the length of the time domain (TD) basis vector or the length of the Doppler domain (DD) basis vector includes: determining the length of the TD basis vector or the length of the DD basis vector based on the Doppler offset information and Doppler spread reported from the terminal device, The channel state information feedback method according to claim 13, characterized in that.

22. The step of determining the precoding matrix corresponding to different times based on the codebook indication information includes: determining the precoding matrix corresponding to different times using a codebook structure or a precoding matrix indicator (PMI) prediction algorithm based on the codebook indication information and the determination method of the length of the TD basis vector or the length of the DD basis vector, The channel state information feedback method according to any one of claims 13 to 21, characterized in that.

23. A communication device, A processing module for determining codebook indication information corresponding to a data transmission layer based on the length of a time domain (TD) base vector or the length of a Doppler domain (DD) base vector and codebook parameters set by a network-side device, A transceiver module for transmitting channel state information (CSI) including the codebook indication information to the network-side device, wherein the codebook indication information is used to instruct the network-side device to determine precoding matrices corresponding to different times, A communication device characterized by the above. **Claim 24** The processing module determines the length of a time domain (TD) base vector or the length of a Doppler domain (DD) base vector, and determines codebook indication information corresponding to a data transmission layer based on the length and codebook parameters set by the network-side device. The communication device according to claim 23, characterized by the above. **Claim 25** The processing module determines the length of a TD base vector or the length of a DD base vector based on a first parameter set by the network-side device. The communication device according to claim 24, characterized by the above. **Claim 26** The first parameter is the number of channel state information reference signal (CSI-RS) resources or the number of CSI-RS resources within a CSI-RS measurement window, The processing module determines that the length of the TD base vector or the length of the DD base vector is equal to the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within a CSI-RS measurement window, Alternatively, it is determined that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI-RS resources set by the network-side device １ and Alternatively, it is determined that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI-RS resources within the CSI-RS measurement window set by the network-side device １ times, or the length of the TD base vector or the length of the DD base vector is 【Number 15】 is determined to be equal to the said Q １ is a positive integer, and the said N ＣＳＩ－ＲＳ is the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within the CSI-RS measurement window, and the said C ｕ is a compression unit in the time domain The communication device according to claim 25, characterized by the above. **Claim 27** The first parameter is the size of a CSI-RS measurement window and the interval between adjacent CSI measurement times, The processing module the length of the TD base vector or the length of the DD base vector is 【Number 16】 is determined to be equal to the said W ｍｅａｓ where W is the size of the CSI-RS measurement window, d is the interval between adjacent CSI measurement times, or the maximum or minimum interval between adjacent CSI measurements, or the average value of a plurality of adjacent CSI measurement intervals The communication device according to claim 25, characterized by the above. **Claim 28** The first parameter is the number of CSI measurements or the number of CSI measurements within a CSI-RS measurement window, The processing module It is determined that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI measurements set by the network-side device or the number of CSI measurements within the CSI-RS measurement window, Alternatively, it is determined that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI measurements set by the network-side device ２ and Or, the length of the TD basis vector or the length of the DD basis vector is determined to be equal to Q times the number of CSI measurements within the CSI-RS measurement window set by the network-side device ２ times, and or the length of the TD basis vector or the length of the DD basis vector is 【Number 17】 is determined to be equal to the said Q ２ is a positive integer, and the said B is the number of CSI measurements set by the network side device or the number of CSI measurements within the CSI-RS measurement window, and the said C ｕ is a compression unit in the time domain The communication device according to claim 25, characterized in that.

29. The first parameter is parameter W, wherein the processing module, the length of the TD basis vector or the length of the DD basis vector is 【Number 18】 is determined to be equal to, and W mod C ｕ = 0, and the C ｕ is a compression unit in the time domain, or the length of the TD basis vector or the length of the DD basis vector is 【Number 19】 or 【Number 20】 is determined to be equal to, 【Number 21】 the parameter W is, 1) a slot corresponding to the CSI reporting time, 2) a slot where the CSI reference resource is located, 3) a slot corresponding to the left boundary or the right boundary of the CSI-RS measurement window, 4) determined by at least one parameter among a slot corresponding to the left boundary or the right boundary of the CSI reporting window, The communication device according to claim 25, characterized in that.

30. The processing module further, The compression unit C in the time domain ｕ is determined The communication device according to any one of claims 26 to 29, characterized in that.

31. The compression unit C ｕ is αT ｃ where α is an integer of 1 or less, and T ｃ is the channel coherence time, or Or, the compression unit C ｕ is the measurement period of CSI-RS resources, or Or, the compression unit C ｕ is βd １ where β is an integer of 1 or more, and d １ is the measurement interval of adjacent CSIs, or or the compression unit C ｕ is βd ２ where β is an integer of 1 or more, and d ２ is the maximum interval or minimum interval between adjacent CSI measurements, or the average value of a plurality of intervals between adjacent CSI measurements The communication device according to claim 30, characterized in that.

32. wherein the processing module, based on the Doppler offset information and Doppler spread estimated using CSI-RS by the terminal device, determines the length of the TD basis vector or the length of the DD basis vector, The communication device according to claim 24, characterized in that.

33. The transceiver module further, receives the length of the TD basis vector or the length of the DD basis vector set by the network-side device, The communication device according to claim 23, characterized in that.

34. The codebook indication information includes at least one combination of a matrix composed of at least one spatial domain (SD) basis vector, a combination coefficient matrix, a matrix composed of at least one frequency domain (FD) basis vector, and a matrix composed of at least one TD basis vector or DD basis vector, The communication device according to any one of claims 23 to 33, characterized in that.

35. A communication device, comprising a processing module and a transceiver module The processing module determines the length of a time-domain (TD) basis vector or the length of a Doppler-domain (DD) basis vector, and the processing module further sets codebook parameters for the terminal device, and the transceiver module transmits the length of the TD basis vector or the DD basis vector and the codebook parameters to the terminal device, and the transceiver module further receives codebook indication information corresponding to a data transmission layer determined by the length and the codebook parameters from the terminal device, and the processing module further determines a precoding matrix corresponding to different times based on the codebook indication information, wherein the communication device is characterized by the above. **Claim 36** The processing module determines the length of the TD basis vector or the length of the DD basis vector based on a first parameter set by a network-side device. The communication device according to claim 35, wherein the communication device is characterized by the above. **Claim 37** The first parameter is the number of channel state information reference signal (CSI-RS) resources or the number of CSI-RS resources within a CSI-RS measurement window, and the processing module determines that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within a CSI-RS measurement window, Or, it is determined that the length of the TD base vector or the length of the DD base vector is equal to Q times the number of CSI-RS resources set by the network-side device １ and Alternatively, it is determined that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI-RS resources within the CSI-RS measurement window set by the network-side device １ times, and or the length of the TD basis vector or the length of the DD basis vector is 【Number 22】 is determined to be equal to said Q １ is a positive integer, and said N ＣＳＩ－ＲＳ is the number of CSI-RS resources set by the network-side device or the number of CSI-RS resources within a CSI-RS measurement window, and said C ｕ is a compression unit in the time domain The communication device according to claim 35, wherein the communication device is characterized by the above. **Claim 38** The first parameter is the size of the CSI-RS measurement window and the interval between adjacent CSI measurement times, and the processing module the length of the TD basis vector or the length of the DD basis vector is 【Number 23】 is determined to be equal to the said W ｍｅａｓ where W is the size of the CSI-RS measurement window, d is the interval between adjacent CSI measurement times, or the maximum or minimum interval between adjacent CSI measurements, or the average value of a plurality of adjacent CSI measurement intervals The communication device according to claim 36, wherein the communication device is characterized by the above. **Claim 39** The first parameter is the number of CSI measurements or the number of CSI measurements within a CSI-RS measurement window, and the processing module determines that the length of the TD basis vector or the length of the DD basis vector is equal to the number of CSI measurements set by the network-side device or the number of CSI measurements within a CSI-RS measurement window, Alternatively, it is determined that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI measurements set by the network-side device ２ and Alternatively, it is determined that the length of the TD basis vector or the length of the DD basis vector is equal to Q times the number of CSI measurements within the CSI-RS measurement window set by the network-side device ２ times, or the length of the TD basis vector or the length of the DD basis vector is [Number 24] is determined to be equal to the said Q ２ is a positive integer, the said B is the number of CSI measurements set by the network side device or the number of CSI measurements within the CSI-RS measurement window, and the said C ｕ is a compression unit in the time domain The communication device according to claim 36, wherein the communication device is characterized by the above. **Claim 40** The first parameter is parameter W, wherein the processing module, the length of the TD basis vector or the length of the DD basis vector is 【Number 25】 is determined to be equal to, and W mod C ｕ = 0, and the C ｕ is a compression unit in the time domain, or, the length of the TD basis vector or the length of the DD basis vector is 【Number 26】 or 【Number 27】 is determined to be equal, 【Number 28】 the parameter W is 1) a slot corresponding to the CSI reporting time, 2) a slot where the CSI reference resource is located, 3) a slot corresponding to the left or right boundary of the CSI-RS measurement window, 4) a slot corresponding to the left or right boundary of the CSI reporting window, and is determined by at least one parameter among them, The communication device according to claim 36, characterized in that.

41. The processing module further determines a compression unit C in the time domain ｕ thereof. The communication device according to any one of claims 37 to 40, characterized in that.

42. The compression unit C ｕ is αT ｃ where α is an integer of 1 or less, and T ｃ is the channel coherence time, or Or, the compression unit C ｕ is the measurement period of the CSI-RS resource, or or the compression unit C ｕ is βd １ where β is an integer of 1 or more, and d １ is the measurement interval of adjacent CSIs, or or the compression unit C ｕ is βd ２ where β is an integer of 1 or more, and d ２ is the maximum interval or minimum interval between adjacent CSI measurements, or the average value of a plurality of adjacent CSI measurement intervals The communication device according to claim 41, characterized in that.

43. wherein the processing module, based on the Doppler offset information and Doppler spread reported from the terminal device, determines the length of the TD basis vector or the length of the DD basis vector, The communication device according to claim 35, characterized in that.

44. wherein the processing module, based on the codebook indication information and the determination method of the length of the TD basis vector or the length of the DD basis vector, uses a codebook structure or a precoding matrix indicator (PMI) prediction algorithm to determine precoding matrices corresponding to different times, The communication device according to any one of claims 35 to 43, characterized in that.

45. A communication device, comprising a processor and a memory, a computer program is stored in the memory, and the processor executes the computer program stored in the memory to cause the communication device to execute the method according to any one of claims 1 to 12, The communication device characterized by that.

46. A communication device, comprising a processor and a memory, a computer program is stored in the memory, and the processor executes the computer program stored in the memory to cause the communication device to execute the method according to any one of claims 13 to 22, The communication device characterized by that.

47. A computer-readable storage medium storing instructions, When the command is executed, the method according to any one of claims 1 to 12 is realized, A computer-readable storage medium characterized by the above.

48. A computer-readable storage medium storing a command, When the command is executed, the method according to any one of claims 13 to 22 is realized, A computer-readable storage medium characterized by the above.

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