CN109510654B

CN109510654B - Channel state information feedback method and device

Info

Publication number: CN109510654B
Application number: CN201710843069.4A
Authority: CN
Inventors: 高秋彬; 李辉; 拉盖施; 陈润华
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2017-09-14
Filing date: 2017-09-18
Publication date: 2023-05-02
Anticipated expiration: 2037-09-18
Also published as: CN109510654A

Abstract

The application discloses a channel state information feedback method and device. In the application, a terminal performs channel measurement to obtain Channel State Information (CSI), wherein the CSI comprises first CSI and second CSI, the first CSI comprises composition information of the second CSI, and the composition information is used for determining the bit number of the second CSI; and the terminal sends the first CSI and the second CSI to a base station. By adopting the method and the device, the base station can determine the bit quantity of the second CSI according to the first CSI, so that the complexity of detecting the second CSI by the base station is reduced.

Description

Channel state information feedback method and device

The present application claims priority from chinese patent office, application number 201710827964.7, application name "a channel state information feedback method and apparatus", filed on day 14, 9, 2017, the entire contents of which are incorporated herein by reference.

Technical Field

The present invention relates to the field of wireless communications technologies, and in particular, to a method and an apparatus for feeding back channel state information.

Background

The terminal calculates channel state information (channel state information, CSI) by downlink channel measurements. The CSI may include one or more of a Rank Indication (RI), a precoding matrix indication (precoding matrix indicator, PMI), a channel quality indication (Channel Quality Indicator, CQI), and a channel state information reference signal resource indication (CSI-RS resource indicator, CRI) may be further included in the CSI. And the terminal reports the CSI obtained by measurement to the base station according to the uplink resources allocated to the terminal by the base station.

When the terminal performs channel measurement and feedback according to the configured codebook, the load of the reported CSI (i.e., the bit number of the CSI) will dynamically change with different RIs. In a long term evolution (long term evolution, LTE) system, for different codebooks, the CSI load difference caused by different RIs is not large, so that the required uplink channel resources can be allocated according to the maximum possible CSI feedback overhead.

A new wireless communication system (NR system) defines a type I codebook and a type II codebook. The type II codebook is a high-precision codebook for feeding back high-precision channel state information to better support (MU-MIMO) transmission. When the terminal feeds back the CSI according to the type II codebook, 2L (L is more than or equal to 1) merging coefficients are fed back independently for each layer, and each merging coefficient feeds back in a mode of amplitude (comprising a broadband amplitude and one or more subband amplitudes) and one or more subband phases. And if the broadband amplitude value corresponding to one merging coefficient is 0, the subband amplitude and the subband phase corresponding to the merging coefficient do not need to be fed back. In this way, the number of bits occupied by CSI fed back by the terminal is dynamically variable. In this case, the base station cannot know the bit number of the CSI before decoding the CSI, which increases the complexity of the base station for CSI detection.

Disclosure of Invention

The embodiment of the application provides a channel state information feedback method and device, which are used for simplifying the complexity of detecting channel state information by a base station.

In a first aspect, a channel state information feedback method is provided, including:

the method comprises the steps that a terminal performs channel measurement to obtain CSI, wherein the CSI comprises first CSI and second CSI, the first CSI comprises composition information of the second CSI, and the composition information is used for determining the bit number of the second CSI; and the terminal sends the first CSI and the second CSI to a base station.

Optionally, the composition information of the second CSI includes: and indicating information of wideband amplitudes except the wideband amplitude corresponding to the strongest combining coefficient in each of N data layers, wherein N is equal to the value of the rank indication RI determined by the terminal, the RI is used for indicating the number of data layers, and N is an integer greater than or equal to 1.

Optionally, the indication information of the wideband amplitude is used for indicating the wideband amplitude with the value of 0 or non-zero.

Optionally, the indication information of the wideband amplitude is a bitmap, and each 1 bit of the bitmap corresponds to the wideband amplitude of one merging coefficient; if the 1 bit value in the bitmap is 1, the broadband amplitude of the merging coefficient corresponding to the 1 bit value is non-zero; or alternatively, the process may be performed,

And if the 1 bit value in the bitmap is 0, the broadband amplitude of the merging coefficient corresponding to the bit with the value of 0 is non-zero.

Optionally, the second CSI includes: the number of the strongest combining coefficient of each data layer, and the non-zero broadband amplitude except the broadband amplitude corresponding to the strongest combining coefficient in all combining coefficients of each data layer; feedback information of each data layer in each sub-band, wherein the feedback information of one data layer in one sub-band comprises: the data layer has sub-band amplitude and sub-band phase of each merging coefficient in the merging coefficients corresponding to non-zero wideband amplitudes except the wideband amplitude corresponding to the strongest merging coefficient.

Optionally, the composition information of the second CSI includes: and the number of non-zero broadband amplitudes except the broadband amplitude corresponding to the strongest combining coefficient in each data layer in the N data layers is equal to the rank indication RI value determined by the terminal, the RI is used for indicating the number of data layers, and the N is an integer greater than or equal to 1.

Optionally, the first CSI further includes: and RI, the RI is used for indicating the number of data layers.

Optionally, the second CSI includes: the number of the strongest combining coefficient of each data layer, and the broadband amplitude of the combining coefficient except the strongest combining coefficient in all combining coefficients of each data layer; feedback information of each data layer in each sub-band, wherein the feedback information of one data layer in one sub-band comprises: the data layer has sub-band amplitude and sub-band phase of each merging coefficient in the merging coefficients corresponding to non-zero wideband amplitudes except the wideband amplitude corresponding to the strongest merging coefficient.

Optionally, the first CSI or the second CSI includes: twiddle factors and beam selection information.

Optionally, the first CSI or the second CSI further includes a channel quality indicator CQI, where the CQI includes a wideband CQI and/or a subband CQI of each subband.

Optionally, the number of bits of the first CSI does not change with the number of data layers indicated by the RI determined by the terminal, and the number of non-zero wideband amplitudes of each data layer except for the wideband amplitude corresponding to the strongest combining coefficient.

In a second aspect, a channel state information feedback method is provided, including:

the base station receives first Channel State Information (CSI) sent by a terminal, wherein the first CSI comprises composition information of second CSI, and the composition information is used for determining the bit number of the second CSI;

the base station determines the bit quantity of the second CSI according to the first CSI;

and the base station receives the second CSI according to the bit quantity of the second CSI.

Optionally, the first CSI or the second CSI includes a channel quality indicator CQI, where the CQI includes a wideband CQI and/or a subband CQI of each subband.

In a third aspect, a terminal is provided, including:

The measuring module is used for carrying out channel measurement to obtain Channel State Information (CSI), wherein the CSI comprises first CSI and second CSI, the first CSI comprises composition information of the second CSI, and the composition information is used for determining the bit number of the second CSI;

and the sending module is used for sending the first CSI and the second CSI to a base station.

In a fourth aspect, there is provided a base station comprising:

a receiving module, configured to receive first channel state information CSI sent by a terminal, where the first CSI includes component information of a second CSI, where the component information is used to determine a number of bits of the second CSI;

A determining module, configured to determine, according to the first CSI, a bit number of the second CSI;

the receiving module is further configured to receive the second CSI according to the number of bits of the second CSI.

In a fifth aspect, there is provided a communication apparatus comprising: the device comprises a processor, a memory and a transceiver, wherein the processor, the memory and the transceiver are connected through a bus; the processor is configured to read a program in the memory, and execute:

performing channel measurement to obtain Channel State Information (CSI), wherein the CSI comprises first CSI and second CSI, the first CSI comprises composition information of the second CSI, and the composition information is used for determining the bit number of the second CSI;

And transmitting the first CSI and the second CSI to a base station through the transceiver.

In a sixth aspect, there is provided a communication apparatus comprising: the device comprises a processor, a memory and a transceiver, wherein the processor, the memory and the transceiver are connected through a bus; the processor is configured to read a program in the memory, and execute:

receiving first Channel State Information (CSI) sent by a terminal through the transceiver, wherein the first CSI comprises composition information of second CSI, and the composition information is used for determining the bit number of the second CSI;

determining the bit quantity of the second CSI according to the first CSI;

and receiving the second CSI through the transceiver according to the bit quantity of the second CSI.

In a seventh aspect, there is provided a computer storage medium storing computer-executable instructions for causing the computer to perform the method of any one of the first aspects.

In an eighth aspect, there is provided a computer storage medium storing computer-executable instructions for causing the computer to perform the method of any one of the second aspects above.

In the above embodiment of the present application, after CSI is obtained by channel measurement, when CSI is fed back to a base station, the terminal may feed back the first CSI and the second CSI, where the first CSI includes composition information of the second CSI, where the composition information is used to determine the number of bits of the second CSI, so that the base station may determine the number of bits of the second CSI according to the first CSI, thereby reducing complexity of detecting the second CSI by the base station.

Drawings

Fig. 1 is a schematic diagram of a network architecture applicable to an embodiment of the present application;

fig. 2 is a schematic flow chart of CSI feedback performed by a terminal according to an embodiment of the present application;

fig. 3 is a schematic flow chart of CSI fed back by a base station receiving terminal according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a terminal provided in an embodiment of the present application;

fig. 5 is a schematic structural diagram of a base station according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 7 is a schematic structural diagram of a communication device according to another embodiment of the present application.

Detailed Description

In the following, some terms in the embodiments of the present application are explained for easy understanding by those skilled in the art.

(1) In the present embodiment, the terms "network" and "system" are often used interchangeably, but those skilled in the art will understand their meaning.

(2) The term "plurality" in the embodiments of the present application means two or more, and other adjectives are similar thereto.

(3) "and/or", describes an association relationship of an association object, and indicates that there may be three relationships, for example, a and/or B, and may indicate: a exists alone, A and B exist together, and B exists alone. The character "/" generally indicates that the context-dependent object is an "or" relationship.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.

Fig. 1 schematically illustrates one possible communication scenario provided by an embodiment of the present application. As shown in fig. 1, a terminal 110 accesses a wireless network through a radio access network (radio access network, RAN) node 120 to acquire a service of an external network (e.g., the internet) through the wireless network or to communicate with other terminals through the wireless network.

A terminal is also called a User Equipment (UE), a Mobile Station (MS), a Mobile Terminal (MT), etc., and is a device that provides voice and/or data connectivity to a user, such as a handheld device, a vehicle-mounted device, etc., with a wireless connection function. Currently, some examples of terminals are: a mobile phone, a tablet, a notebook, a palm, a mobile internet device (mobile internet device, MID), a wearable device, a Virtual Reality (VR) device, an augmented reality (augmented reality, AR) device, a wireless terminal in industrial control (industrial control), a wireless terminal in unmanned (self driving), a wireless terminal in teleoperation (remote medical surgery), a wireless terminal in smart grid (smart grid), a wireless terminal in transportation security (transportation safety), a wireless terminal in smart city (smart city), a wireless terminal in smart home (smart home), and the like.

The RAN is the part of the network that accesses terminals to the wireless network. The RAN node (or device) is a node (or device) in a radio access network, which may also be referred to as a base station. Currently, some examples of RAN nodes are: a gNB, a transmission and reception point (transmission reception point, TRP), an evolved Node B (eNB), a radio network controller (radio network controller, RNC), a Node B (Node B, NB), a base station controller (base station controller, BSC), a base transceiver station (base transceiver station, BTS), a home base station (e.g., home evolved NodeB, or home Node B, HNB), a baseband unit (BBU), or a wireless fidelity (wireless fidelity, wifi) Access Point (AP), etc. In addition, in one network architecture, the RAN may include Centralized Unit (CU) nodes and Distributed Unit (DU) nodes. The structure splits the protocol layer of the eNB in a long term evolution (long term evolution, LTE) system, the functions of part of the protocol layer are controlled in a CU (central control unit), and the functions of the rest part or all of the protocol layer are distributed in DUs, so that the CU controls the DUs in a centralized manner.

The network architecture described in the embodiments of the present application is for more clearly describing the technical solution of the embodiments of the present application, and is not limited to the technical solution provided in the embodiments of the present application, and as a person of ordinary skill in the art can know that, along with the evolution of the network architecture, the technical solution provided in the embodiments of the present application is also applicable to similar technical problems.

According to the embodiment of the application, a CSI feedback method is provided for the problem of dynamic change of feedback bit numbers based on a Type II codebook in an NR system. In the embodiment of the present invention, the CSI fed back by the terminal includes a first CSI and a second CSI, where the number of bits of the first CSI is irrelevant to the feedback content, and the first CSI includes composition information of the second CSI, so as to help the base station determine the number of bits of the second CSI, thereby reducing complexity of detecting the second CSI by the base station.

Embodiments of the present application are described in detail below with reference to the accompanying drawings.

Referring to fig. 2, for a CSI feedback process implemented at a terminal side provided in an embodiment of the present application, as shown in the drawing, the process may include:

s201: and the terminal performs channel measurement to obtain Channel State Information (CSI). The CSI comprises a first CSI and a second CSI, wherein the first CSI comprises composition information of the second CSI, and the composition information is used for determining the bit quantity of the second CSI.

In this step, CSI for feedback obtained by the terminal performing channel measurement based on the type II codebook may include:

-rotation factor and beam selection information for indicating terminal selected two-dimensional discrete fourier transform (Discrete Fourier Transform, DFT) beams and being orthogonal between the beams; the number of the wave beams selected by the terminal is L, and the value of L is configured by the base station through a high-layer signaling;

For each data layer (data stream), 2L combining coefficients need to be reported, each combining coefficient feeding back in amplitude and phase. The magnitude of each combining coefficient includes two parts: broadband amplitude and subband amplitude. The wideband amplitude is an amplitude value calculated in the whole bandwidth range, the sub-band amplitude is an amplitude value calculated in one sub-band range, and each sub-band corresponds to one sub-band amplitude value. The phase of each combining coefficient is a subband phase calculated and fed back for each subband by a pointer. The subband amplitude and subband phase are optional, i.e. when the wideband amplitude of a combining coefficient takes on zero, the subband amplitude and subband phase of the combining coefficient may not be fed back;

-the number of the strongest combining coefficient for each data layer. For one data layer, the broadband amplitude of the strongest combining coefficient is 1, the broadband amplitudes of the rest combining coefficients are obtained by normalizing the broadband amplitude of the strongest combining coefficient and then quantizing, and the broadband amplitude is in the range of [0,1]. The value of the broadband amplitude of the strongest combining coefficient is fixed to be 1, and the value of the sub-band phase is fixed to be 0, so that the number of the strongest combining coefficient in 2L combining coefficients is only needed to be reported without reporting the broadband amplitude and the sub-band phase.

Wideband CQI, and/or subband CQI for each subband.

The terminal can obtain the first CSI and the second CSI according to the CSI.

The first CSI comprises composition information of the second CSI, and the composition information is used for determining the bit quantity of the second CSI.

Optionally, in some embodiments of the present application, the composition information of the second CSI may include: the number of non-zero broadband amplitudes except the width amplitude corresponding to the strongest combining coefficient in each data layer of N data layers (N is an integer greater than or equal to 1), N is equal to the RI value determined by the terminal, and the RI is used for indicating the number of data layers. The number of non-zero wideband amplitudes of the data layer except the width amplitude corresponding to the strongest combining coefficient refers to the number of wideband amplitudes with non-zero value in the wideband amplitudes corresponding to all combining coefficients in 2L-1 combining coefficients of the data layer except the strongest combining coefficient, for example, if the number of the combining coefficient increases from 1, and if L is equal to 3, 6 combining coefficients need to be fed back for one data layer. For the data layer 1, the merging coefficient 2 is the strongest merging coefficient, and the bandwidth amplitude of the merging coefficient 3 takes a value of zero, so that the number of non-zero bandwidth amplitudes of the data layer 1 is 4, and the numbers of the corresponding merging coefficients are {1,4,5,6}, respectively.

For 2L combining coefficients of a data layer, the number of non-zero wideband amplitudes other than the width amplitude corresponding to the strongest combining coefficient may be 0,1,2, …,2L-1 (the wideband amplitude of the strongest combining coefficient must be non-zero and thus the number of non-zero wideband amplitudes other than the width amplitude corresponding to the strongest combining coefficient is not included here), and the number of non-zero wideband amplitudes other than the width amplitude corresponding to the strongest combining coefficient of a data layer may be 2L total possible values, and thus the number of non-zero wideband amplitudes other than the width amplitude corresponding to the strongest combining coefficient of a data layer may be used

A feedback of a number of bits, wherein ∈>

Representing an upward rounding. For example, if RI takes the value of m (m>=1), m "number of non-zero wideband amplitudes except for the width amplitude corresponding to the strongest combining coefficient" is included in the first CSI (i.e., there is one "number of non-zero wideband amplitudes except for the width amplitude corresponding to the strongest combining coefficient" corresponding to one data layer).

Further, the first CSI may further include one or any combination of the following information: RI, twiddle factor, beam selection information. Of course, the rotation factor and the beam selection information described above may be included in the second CSI instead of the first CSI.

The number of bits of the first CSI is independent of the number of data layers indicated by the RI determined by the terminal and the number of non-zero wideband amplitudes of each data layer except for the width amplitude corresponding to the strongest combining coefficient. That is, the number of bits of the first CSI does not vary with the number of data layers indicated by the RI determined by the terminal and the number of non-zero wideband amplitudes of each data layer except for the wideband amplitude corresponding to the strongest combining coefficient.

In order to ensure that the bit number of the first CSI does not change along with the RI value, the bit number occupied by the non-zero broadband amplitude number except the width amplitude corresponding to the strongest combining coefficient can be set according to the maximum RI value. The maximum RI value is the maximum RI value which can be selected by the terminal, and the base station is configured to the terminal through signaling or is agreed in a protocol. For example, if the large RI value is n (n > =1), the first CSI always includes n numbers of non-zero wideband amplitudes, no matter what RI value is. If RI is m and m < n, the first m numbers of non-zero wideband amplitude are numbers of non-zero wideband amplitude corresponding to the data layer, and the rest n-m numbers of non-zero wideband amplitude are filled with fixed bits or filled with invalid values.

The second CSI may include:

-number of strongest combining coefficient of each data layer, dividing all combining coefficients of each data layer by the most

Wideband amplitude of combining coefficients other than strong combining coefficients;

-feedback information per data layer per subband, wherein feedback information per data layer per subband comprises: the data layer has a subband amplitude and a subband phase of each merging coefficient in the merging coefficients corresponding to the non-zero wideband amplitude except the width amplitude corresponding to the strongest merging coefficient.

If the wideband amplitude of one combining coefficient takes a value of 0, the amplitude and phase of each sub-band of the combining coefficient are not included in the second CSI information because the combining coefficient is 0 regardless of the sub-band amplitude and phase in the case where the wideband amplitude takes a value of 0.

Alternatively, the CQI may be included in the first CSI or may be included in the second CSI. Specifically, if the number of bits occupied by the CQI is irrelevant to the RI value, the CQI may be included in the first CSI or the second CSI; if the number of bits occupied by the CQI is related to the RI value, the CQI may be included in the second CSI.

Optionally, in some other embodiments of the present application, the composition information of the second CSI may include: and indicating information of wideband amplitudes except the wideband amplitude corresponding to the strongest combining coefficient in each of N (N is an integer greater than or equal to 1) data layers, wherein N is equal to the RI value determined by the terminal, and the RI is used for indicating the number of data layers. Alternatively, the indication information of the wideband amplitude may be used to indicate a wideband amplitude having a value of 0 or non-zero.

Alternatively, in implementation, the indication information of the wideband amplitude is a bitmap, where each 1 bit of the bitmap corresponds to a wideband amplitude of a merging coefficient. For example, a data layer may correspond to a bitmap having the same number of bits as the number of merging coefficients corresponding to the data layer, and each bit in the bitmap corresponds to a wideband amplitude of the merging coefficients. As an example, if the 1 bit in the bitmap has a value of 1, the wideband amplitude of the merging coefficient corresponding to the 1 bit is non-zero. As another example, if a 1 bit in the bitmap has a value of 0, the wideband amplitude of the merging coefficient corresponding to the bit having the value of 0 is non-zero.

In this case, the second CSI may include contents as described above. To further reduce the overhead, the wideband amplitude with a value of 0 may not be included in the second CSI. For example, for data layer 1, the wideband amplitude of the combining coefficient numbered {1,4,5,6} takes on a value of 0, and the wideband amplitude of the combining coefficient numbered {1,4,5,6} is not included in the second CSI.

S202: and the terminal sends the first CSI and the second CSI to the base station.

In this step, the terminal may perform channel coding and modulation on the first CSI and the second CSI, respectively, and send the first CSI according to the uplink resources allocated for the first CSI, and send the second CSI according to the uplink resources allocated for the second CSI.

Referring to fig. 3, for a CSI feedback process implemented at a base station side according to an embodiment of the present application, as shown in the drawing, the process may include:

s301: the base station receives first CSI sent by a terminal, wherein the first CSI comprises composition information of second CSI, and the composition information is used for determining the bit number of the second CSI.

The information contained in the first CSI and the second CSI can refer to the foregoing embodiments, and are not repeated here.

Optionally, in some examples, the composition information of the second CSI included in the first CSI includes: and the number of non-zero broadband amplitudes of each data layer except the width amplitude corresponding to the strongest combining coefficient in the N data layers is equal to the RI value determined by the terminal, wherein the RI is used for indicating the number of data layers, and N is an integer greater than or equal to 1.

Optionally, in some other examples, the composition information of the second CSI includes: and indicating information of wideband amplitudes except the wideband amplitude corresponding to the strongest combining coefficient in each of N data layers, wherein N is equal to the value of the rank indication RI determined by the terminal, the RI is used for indicating the number of data layers, and N is an integer greater than or equal to 1.

S302: and the base station determines the bit quantity of the second CSI according to the first CSI.

Specifically, if the composition information of the second CSI in the first CSI is the number of non-zero wideband amplitudes of each data layer except for the wideband amplitude corresponding to the strongest combining coefficient in the N data layers, the base station may determine the number of data layers according to RI included in the first CSI, and calculate the number of bits occupied by the feedback information corresponding to each data layer according to the "number of non-zero wideband amplitudes of each data layer except for the wideband amplitude corresponding to the strongest combining coefficient" included in the first CSI, where the number includes the number of strongest combining coefficient of each data layer, the non-zero wideband amplitudes of all combining coefficients of each data layer except for the wideband amplitude corresponding to the strongest combining coefficient, and the number of bits occupied by the subband amplitude and subband phase of each combining coefficient.

If the composition information of the second CSI in the first CSI is the indication information of the wideband amplitudes of each data layer except the wideband amplitude corresponding to the strongest combining coefficient in the N data layers, for example, taking the indication information as a bitmap (the wideband amplitude of one combining coefficient is corresponding to each 1 bit of the bitmap, if the 1 bit in the bitmap is 1, the wideband amplitude of the combining coefficient corresponding to the 1 bit is non-zero), the base station may determine the number of the bitmap according to the RI contained in the first CSI, determine the number of bits occupied by the feedback information corresponding to each data layer according to the wideband amplitude of the non-zero indicated in each bitmap, and calculate the number of bits occupied by the feedback information corresponding to each data layer, including the number of the strongest combining coefficient of each data layer, the non-zero wideband amplitudes of all the combining coefficients of each data layer except the wideband amplitude corresponding to the strongest combining coefficient, and the number of sub-bands and the number of bits occupied by the sub-band phases of each combining coefficient.

S303: and the base station receives the second CSI according to the bit quantity of the second CSI.

In this step, the base station may receive the second CSI according to the number of bits of the second CSI determined in S302, and demodulate and decode the second CSI. Further, the base station can obtain the CSI fed back by the terminal according to the received first CSI and the second CSI.

In order to more clearly understand the present application, the following describes the above embodiments of the present application in detail in connection with a specific application scenario.

In this scenario, the base station configures a codebook of 32-port type II for the terminal, where the codebook parameter l=3, and CSI feedback needs to be performed for 10 subbands. The terminal performs channel measurement and CSI feedback based on the Type II codebook, and the CSI required to be fed back comprises: rotation factor, beam selection information, strongest coefficient number, wideband amplitude for each coefficient, subband amplitude and subband phase, etc.

Regarding the feedback overhead of CSI, there is the following convention:

the system supports a maximum of 8 data layers, so the predefined RI overhead is 3 bits (i.e., 3 bits are used to represent the RI value). The number of data layers is represented by rank, i.e., the RI value. The RI configured for the terminal has a value range {1,2}, and when rank=1 or 2, there is only one codeword, that is, only one CQI per subband, and the CQI per subband occupies 4 bits, regardless of the value of RI.

Since the codebook parameter l=3, the terminal needs to report 6 (i.e. 2L) combining coefficients for each data layer, the wideband amplitude of each combining coefficient occupies 3 bits, the subband amplitude occupies 1 bit, and the subband phase occupies 2 bits.

According to the above procedure on the terminal side shown in fig. 2, in S201, the terminal performs channel measurement based on the 32-port type II codebook configured by the base station for the terminal, and determines ri=2 (i.e. the data layers are 2 layers: a first data layer and a second data layer). The CSI measured by the terminal includes:

RI, twiddle factor, beam selection information;

-the number of the strongest combining coefficient of the 6 (i.e. 2L) combining coefficients of the first data layer, the number of the strongest combining coefficient of the 6 (i.e. 2L) combining coefficients of the second data layer, the wideband magnitudes of the remaining 5 combining coefficients of the 6 combining coefficients of the first data layer, excluding the strongest combining coefficient, the wideband magnitudes of the 5 combining coefficients of the 6 combining coefficients of the second data layer, excluding the strongest combining coefficient;

-the combining coefficients of the first data layer and the second data layer comprise, at each subband, a subband amplitude and a subband phase, comprising:

the subband magnitudes of the remaining 5 merging coefficients except the strongest merging coefficient of the 6 merging coefficients of the first data layer, and the subband magnitudes of the remaining 5 merging coefficients except the strongest merging coefficient of the 6 merging coefficients of the second data layer;

sub-band phases of the remaining 5 merging coefficients except the strongest merging coefficient of the 6 merging coefficients of the first data layer, and sub-band phases of the remaining 5 merging coefficients except the strongest merging coefficient of the 6 merging coefficients of the second data layer;

-CQI: wideband CQI and/or sub-band CQI per sub-band.

Wherein, 4 of the remaining 5 (i.e. 2L-1) wideband amplitude values except the strongest combining coefficient in the 6 combining coefficients of the first data layer are non-zero values, and 3 of the remaining 5 (i.e. 2L-1) wideband amplitude values except the strongest combining coefficient in the 6 combining coefficients of the second data layer are non-zero values.

Based on this, the terminal determining the first CSI includes: RI, twiddle factor, beam selection information, CQI, and the number of non-zero wideband amplitudes of the first data layer (4) except for the width amplitude corresponding to the strongest combining coefficient and the number of non-zero wideband amplitudes of the second data layer (3) except for the width amplitude corresponding to the strongest combining coefficient. Alternatively, the terminal determining the first CSI includes: RI, twiddle factor, wave beam selection information, CQI, bit map 1 corresponding to the first data layer and bit map 2 corresponding to the second data layer, wherein, the bit map 1 and the bit map 2 both contain 6 bits, the broadband amplitude corresponding to the bit with the value of 1 is non-zero broadband amplitude except the broadband amplitude corresponding to the strongest merging coefficient, 4 bits with the value of 1 are arranged in the bit map 1, and 3 bits with the value of 1 are arranged in the bit map 2.

The terminal determining the second CSI includes:

-the number of the strongest combining coefficient of the first data layer, the wideband magnitudes of the remaining 5 combining coefficients of the 6 combining coefficients of the first data layer, excluding the strongest combining coefficient; the number of the strongest combining coefficient of the second data layer, and the wideband amplitude of the rest 5 combining coefficients except the strongest combining coefficient in the 6 combining coefficients of the second data layer;

-feedback information corresponding to 10 subbands, wherein the feedback information corresponding to each subband comprises:

the first data layer comprises a sub-band amplitude and a sub-band phase of each merging coefficient in 4 merging coefficients corresponding to 4 non-zero broadband amplitudes except the width amplitude corresponding to the strongest merging coefficient;

the subband amplitude and subband phase of each merging coefficient in the 3 merging coefficients corresponding to the 3 non-zero wideband amplitudes of the second data layer except the width amplitude corresponding to the strongest merging coefficient.

In the second CSI, the arrangement sequence of the subband amplitude and the subband phase of the combining coefficient is consistent with the arrangement sequence of the non-zero wideband amplitude of the combining coefficient. For example, the 5 wideband amplitudes of the first data layer are { P1, P2, P3, P4, P5}, where p2=0, the subband amplitudes of the combining coefficients of the first data layer on one subband are arranged { q1, q3, q4, q5}, and the arrangement order of the subband phases is { s1, s3, s4, s5}.

In S202, the terminal encodes the first CSI and the second CSI independently, and feeds back the first CSI and the second CSI to the base station according to uplink resources allocated by the base station.

According to the flow on the base station side shown in fig. 3, in S301, the base station receives the first CSI information sent by the terminal, and decodes the following information: RI (ri=2), twiddle factor, beam selection information, CQI, and the number of non-zero wideband amplitudes of the first data layer (value 4) except for the width amplitude corresponding to the strongest combining coefficient, and the number of non-zero wideband amplitudes of the second data layer (value 3) except for the width amplitude corresponding to the strongest combining coefficient.

In S302, the base station calculates the number of bits of the second CSI:

the number of the strongest combining coefficient of the first data layer occupies 3 bits, and the wideband amplitude of the remaining 5 combining coefficients except the strongest combining coefficient of the 6 combining coefficients of the first data layer occupies 15 bits (5 combining coefficients×3 bits=15 bits); the number of the strongest combining coefficient of the second data layer occupies 3 bits, and the wideband amplitude of the remaining 5 combining coefficients except the strongest combining coefficient of the 6 combining coefficients of the second data layer occupies 15 bits (5 combining coefficients×3 bits=15 bits);

The base station calculates feedback information corresponding to 10 sub-bands according to the number of non-zero wideband amplitudes (with a value of 4) of the first data layer and the number of non-zero wideband amplitudes (with a value of 3) of the second data layer, wherein the feedback information corresponding to each sub-band comprises:

the sub-band phase and sub-band amplitude of the 4 merging coefficients corresponding to the 4 non-zero wideband amplitudes of the first data layer occupy 12 bits, wherein the sub-band amplitude of each merging coefficient occupies 1 bit, the sub-band amplitude of the 4 merging coefficients occupies 4 bits, the sub-band phase of each merging coefficient occupies 2 bits, and the sub-band phase of the 4 merging coefficients occupies 8 bits;

the subband phase and subband amplitude of the 3 merging coefficients corresponding to the 3 non-zero wideband amplitudes of the second data layer occupy 9 bits, wherein the subband amplitude of each merging coefficient occupies 1 bit, the subband amplitude of the 3 merging coefficients occupies 3 bits, the subband phase of each merging coefficient occupies 2 bits, and the subband phase of the 3 merging coefficients occupies 6 bits.

The feedback information corresponding to each sub-band occupies 21 bits, and the feedback information corresponding to 10 sub-bands occupies 210 bits.

Thus, the second CSI occupies 246 bits in total.

In S303, the base station receives the second CSI according to the calculated bit number of the second CSI, and determines a combining coefficient corresponding to the non-zero wideband amplitude according to the 5 wideband amplitudes of the first data layer (except the wideband amplitude of the strongest combining coefficient) and the 5 wideband amplitudes of the second data layer (except the wideband amplitude of the strongest combining coefficient) in the second CSI. Wherein:

for each combining coefficient other than the strongest combining coefficient, if its wideband amplitude is equal to 0, the combining coefficient is 0; if the wideband amplitude is not equal to 0, the wideband amplitude is combined with the sub-band amplitude and the sub-band phase according to the sub-band amplitude and the sub-band phase of the combining coefficient in each sub-band, and the value of the combining coefficient in each sub-band is obtained.

As can be seen from the above description, in the above embodiments of the present application, after CSI is obtained by channel measurement, when CSI is fed back to a base station, the terminal may feed back the first CSI and the second CSI, where the first CSI includes composition information of the second CSI, and the composition information is used to determine the number of bits of the second CSI, so that the base station may determine the number of bits of the second CSI according to the first CSI, thereby reducing complexity of detecting the second CSI by the base station.

Based on the same technical concept, the embodiment of the application also provides a terminal, which can realize the functions of the terminal side in the embodiment.

Referring to fig. 4, a schematic structural diagram of a terminal provided in an embodiment of the present application, as shown in the drawing, the terminal may include: a measurement module 401, a transmission module 402, wherein:

the measurement module 401 is configured to perform channel measurement to obtain CSI, where the CSI includes a first CSI and a second CSI, and the first CSI includes composition information of the second CSI, where the composition information is used to determine a number of bits of the second CSI; the sending module 402 is configured to send the first CSI and the second CSI to a base station.

Based on the same technical concept, the embodiment of the application also provides a base station, which can realize the functions of the base station side in the previous embodiment.

Referring to fig. 5, a schematic structural diagram of a base station according to an embodiment of the present application is shown, where as shown in the drawing, the base station may include: a receiving module 501, a determining module 502, wherein:

the receiving module 501 is configured to receive a first CSI sent by a terminal, where the first CSI includes composition information of a second CSI, and the composition information is used to determine a number of bits of the second CSI; the determining module 502 is configured to determine, according to the first CSI, a bit number of the second CSI; the receiving module 501 is further configured to receive the second CSI according to the number of bits of the second CSI.

Based on the same technical concept, the embodiment of the application also provides a communication device, which can realize the functions of the terminal side in the previous embodiment.

Referring to fig. 6, a schematic structural diagram of a communication device according to an embodiment of the present application is shown, where the communication device may include: processor 601, memory 602, transceiver 603 and bus interface.

The processor 601 is responsible for managing the bus architecture and general processing, and the memory 602 may store data used by the processor 601 in performing operations. The transceiver 603 is used to receive and transmit data under the control of the processor 601.

The bus architecture may comprise any number of interconnecting buses and bridges, and in particular one or more processors represented by the processor 601 and various circuits of the memory, represented by the memory 602, are linked together. The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, power management circuits, etc., which are well known in the art and, therefore, will not be described further herein. The bus interface provides an interface. The processor 601 is responsible for managing the bus architecture and general processing, and the memory 602 may store data used by the processor 601 in performing operations.

The flow disclosed in the embodiment of the present invention may be applied to the processor 601 or implemented by the processor 601. In implementation, the steps of the signal processing flow may be performed by integrated logic circuits of hardware in the processor 601 or instructions in the form of software. The processor 601 may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, and may implement or perform the methods, steps and logic blocks disclosed in embodiments of the invention. The general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present invention may be embodied directly in a hardware processor for execution, or in a combination of hardware and software modules in the processor for execution. The software modules may be located in a random access memory, flash memory, read only memory, programmable read only memory, or electrically erasable programmable memory, registers, etc. as well known in the art. The storage medium is located in the memory 602, and the processor 601 reads the information in the memory 602, and completes the steps of the signal processing flow in combination with the hardware.

Specifically, the processor 601 is configured to read a program in the memory 602 and execute: performing channel measurement to obtain CSI, wherein the CSI comprises first CSI and second CSI, the first CSI comprises composition information of the second CSI, and the composition information is used for determining the bit number of the second CSI; and transmitting the first CSI and the second CSI to a base station through the transceiver.

Based on the same technical concept, the embodiment of the application also provides a communication device, which can realize the functions of the base station side in the previous embodiment.

Referring to fig. 7, a schematic structural diagram of a communication device according to an embodiment of the present application is shown, where the communication device may include: a processor 701, a memory 702, a transceiver 703 and a bus interface.

The processor 701 is responsible for managing the bus architecture and general processing, and the memory 702 may store data used by the processor 701 in performing operations. The transceiver 703 is used to receive and transmit data under the control of the processor 701.

A bus architecture may comprise any number of interconnecting buses and bridges, and in particular one or more processors represented by the processor 701 and various circuits of memory represented by the memory 702. The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, power management circuits, etc., which are well known in the art and, therefore, will not be described further herein. The bus interface provides an interface. The processor 701 is responsible for managing the bus architecture and general processing, and the memory 702 may store data used by the processor 701 in performing operations.

The flow disclosed in the embodiments of the present invention may be applied to the processor 701 or implemented by the processor 701. In implementation, the steps of the signal processing flow may be performed by integrated logic circuits of hardware in the processor 701 or instructions in the form of software. The processor 701 may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, and may implement or perform the methods, steps and logic blocks disclosed in embodiments of the invention. The general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present invention may be embodied directly in a hardware processor for execution, or in a combination of hardware and software modules in the processor for execution. The software modules may be located in a random access memory, flash memory, read only memory, programmable read only memory, or electrically erasable programmable memory, registers, etc. as well known in the art. The storage medium is located in the memory 702, and the processor 701 reads the information in the memory 702, and completes the steps of the signal processing flow in combination with its hardware.

Specifically, the processor 701 is configured to read a program in the memory 702 and execute: receiving first Channel State Information (CSI) sent by a terminal through a transceiver, wherein the first CSI comprises composition information of second CSI, and the composition information is used for determining the bit number of the second CSI; determining the bit quantity of the second CSI according to the first CSI; and receiving the second CSI through the transceiver according to the bit quantity of the second CSI.

In the foregoing apparatus shown in fig. 4, fig. 5, fig. 6, and fig. 7, optionally, the composition information of the second CSI includes: and indicating information of wideband amplitudes except the wideband amplitude corresponding to the strongest combining coefficient in each of N data layers, wherein N is equal to the value of the rank indication RI determined by the terminal, the RI is used for indicating the number of data layers, and N is an integer greater than or equal to 1.

Optionally, the indication information of the wideband amplitude is a bitmap, and each 1 bit of the bitmap corresponds to the wideband amplitude of one merging coefficient; if the 1 bit value in the bitmap is 1, the broadband amplitude of the merging coefficient corresponding to the 1 bit value is non-zero; or if the 1 bit value in the bitmap is 0, the wideband amplitude of the merging coefficient corresponding to the bit with the value of 0 is non-zero.

In the foregoing apparatus shown in fig. 4, fig. 5, fig. 6, and fig. 7, optionally, the composition information of the second CSI includes: and the number of non-zero broadband amplitudes except the broadband amplitude corresponding to the strongest combining coefficient in each data layer in the N data layers is equal to the rank indication RI value determined by the terminal, the RI is used for indicating the number of data layers, and the N is an integer greater than or equal to 1.

In the foregoing apparatus shown in fig. 4, fig. 5, fig. 6, and fig. 7, optionally, the first CSI further includes: and RI, the RI is used for indicating the number of data layers.

In the foregoing apparatus shown in fig. 4, fig. 5, fig. 6, and fig. 7, optionally, the second CSI includes: the number of the strongest combining coefficient of each data layer, and the broadband amplitude of the combining coefficient except the strongest combining coefficient in all combining coefficients of each data layer; feedback information of each data layer in each sub-band, wherein the feedback information of one data layer in one sub-band comprises: the data layer has sub-band amplitude and sub-band phase of each merging coefficient in the merging coefficients corresponding to non-zero wideband amplitudes except the wideband amplitude corresponding to the strongest merging coefficient.

In the foregoing apparatus shown in fig. 4, fig. 5, fig. 6, and fig. 7, optionally, the first CSI or the second CSI includes: twiddle factors and beam selection information.

In the apparatus shown in fig. 4, fig. 5, fig. 6 and fig. 7, optionally, the first CSI or the second CSI further includes a channel quality indicator CQI, where the CQI includes a wideband CQI and/or a subband CQI of each subband.

In the foregoing apparatus shown in fig. 4, fig. 5, fig. 6, and fig. 7, optionally, the number of bits of the first CSI does not change with the number of data layers indicated by the RI determined by the terminal, and the number of non-zero wideband amplitudes of each data layer except for the wideband amplitude corresponding to the strongest combining coefficient.

Based on the same technical concept, the embodiment of the application also provides a computer storage medium. The computer-readable storage medium stores computer-executable instructions for causing the computer to execute the procedure executed on the terminal side in the foregoing embodiment.

Based on the same technical concept, the embodiment of the application also provides a computer storage medium. The computer-readable storage medium stores computer-executable instructions for causing the computer to execute the procedure executed on the base station side in the foregoing embodiment.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the application.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present application without departing from the spirit or scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims and the equivalents thereof, the present application is intended to cover such modifications and variations.

Claims

1. A channel state information feedback method, comprising:

The method comprises the steps that a terminal performs channel measurement to obtain Channel State Information (CSI), wherein the CSI comprises first CSI and second CSI, the first CSI comprises composition information of the second CSI, and the composition information is used for determining the bit number of the second CSI; wherein, the composition information of the second CSI includes: the method comprises the steps that indication information of non-zero broadband amplitude except broadband amplitude corresponding to the strongest combining coefficient in each data layer of N data layers is equal to a rank indication RI value determined by the terminal, the RI is used for indicating the number of data layers, and N is an integer greater than or equal to 1; wherein, the indication information of the non-zero broadband amplitude is a bitmap, one data layer corresponds to one bitmap, and each 1 bit of each bitmap corresponds to the broadband amplitude of one merging coefficient; the bit number of the first CSI does not change along with the difference of the numbers of the non-zero broadband amplitudes except the broadband amplitude corresponding to the strongest combining coefficient of each data layer;

and the terminal sends the first CSI and the second CSI to a base station.

2. The method of claim 1, wherein,

if the 1 bit value in the bitmap is 1, the broadband amplitude of the merging coefficient corresponding to the 1 bit value is non-zero; or alternatively, the process may be performed,

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

the number of the strongest combining coefficient of each data layer, and the non-zero broadband amplitude except the broadband amplitude corresponding to the strongest combining coefficient in all combining coefficients of each data layer;

feedback information of each data layer in each sub-band, wherein the feedback information of one data layer in one sub-band comprises: the data layer has sub-band amplitude and sub-band phase of each merging coefficient in the merging coefficients corresponding to non-zero wideband amplitudes except the wideband amplitude corresponding to the strongest merging coefficient.

4. The method of any of claims 1 to 3, wherein the second CSI comprises:

the number of the strongest combining coefficient of each data layer, and the broadband amplitude of the combining coefficient except the strongest combining coefficient in all combining coefficients of each data layer;

5. The method of claim 1, wherein the first CSI further comprises: and RI, the RI is used for indicating the number of data layers.

6. The method of claim 1, wherein the first CSI or the second CSI comprises: twiddle factors and beam selection information.

7. The method of claim 1, wherein the first CSI or the second CSI further comprises a channel quality indicator, CQI, comprising a wideband CQI and/or a subband CQI for each subband.

8. The method according to any of claims 1 to 3, 5 to 7, wherein the number of bits of the first CSI does not vary with the number of data layers indicated by the RI determined by the terminal.

9. A channel state information feedback method, comprising:

the base station receives first Channel State Information (CSI) sent by a terminal, wherein the first CSI comprises composition information of second CSI, and the composition information is used for determining the bit number of the second CSI; wherein, the composition information of the second CSI includes: the method comprises the steps that indication information of non-zero broadband amplitude except broadband amplitude corresponding to the strongest combining coefficient in each data layer of N data layers is equal to a rank indication RI value determined by the terminal, the RI is used for indicating the number of data layers, and N is an integer greater than or equal to 1; wherein, the indication information of the non-zero broadband amplitude is a bitmap, one data layer corresponds to one bitmap, and each 1 bit of each bitmap corresponds to the broadband amplitude of one merging coefficient; the bit number of the first CSI does not change along with the difference of the numbers of the non-zero broadband amplitudes except the broadband amplitude corresponding to the strongest combining coefficient of each data layer;

10. The method of claim 9, wherein,

11. The method of claim 9, wherein the second CSI comprises:

12. The method according to any of claims 9 to 11, wherein the second CSI comprises:

13. The method of claim 9, wherein the first CSI further comprises: and RI, the RI is used for indicating the number of data layers.

14. The method of claim 9, wherein the first CSI or the second CSI comprises: twiddle factors and beam selection information.

15. The method of claim 9, wherein the first CSI or the second CSI comprises a channel quality indication, CQI, comprising a wideband CQI and/or a subband CQI for each subband.

16. The method according to any of claims 9 to 11, 13 to 15, wherein the number of bits of the first CSI does not vary with the number of data layers indicated by the RI determined by the terminal.

17. A terminal, comprising:

the measuring module is used for carrying out channel measurement to obtain Channel State Information (CSI), wherein the CSI comprises first CSI and second CSI, the first CSI comprises composition information of the second CSI, and the composition information is used for determining the bit number of the second CSI; wherein, the composition information of the second CSI includes: the method comprises the steps that indication information of non-zero broadband amplitude except broadband amplitude corresponding to the strongest combining coefficient in each data layer of N data layers is equal to a rank indication RI value determined by the terminal, the RI is used for indicating the number of data layers, and N is an integer greater than or equal to 1; wherein, the indication information of the non-zero broadband amplitude is a bitmap, each 1 bit of the bitmap corresponds to the broadband amplitude of one merging coefficient, one data layer corresponds to one bitmap, and each 1 bit of each bitmap corresponds to the broadband amplitude of one merging coefficient; the bit number of the first CSI does not change along with the difference of the numbers of the non-zero broadband amplitudes except the broadband amplitude corresponding to the strongest combining coefficient of each data layer;

18. A base station, comprising:

a determining module, configured to determine, according to the first CSI, a bit number of the second CSI; wherein, the composition information of the second CSI includes: the method comprises the steps that indication information of non-zero broadband amplitude except broadband amplitude corresponding to the strongest combining coefficient in each data layer of N data layers is equal to a rank indication RI value determined by the terminal, the RI is used for indicating the number of data layers, and N is an integer greater than or equal to 1; wherein, the indication information of the non-zero broadband amplitude is a bitmap, each 1 bit of the bitmap corresponds to the broadband amplitude of one merging coefficient, one data layer corresponds to one bitmap, and each 1 bit of each bitmap corresponds to the broadband amplitude of one merging coefficient; the bit number of the first CSI does not change along with the difference of the numbers of the non-zero broadband amplitudes except the broadband amplitude corresponding to the strongest combining coefficient of each data layer;

19. A communication device, comprising: the device comprises a processor, a memory and a transceiver, wherein the processor, the memory and the transceiver are connected through a bus; the processor is configured to read a program in the memory, and execute:

Performing channel measurement to obtain Channel State Information (CSI), wherein the CSI comprises first CSI and second CSI, the first CSI comprises composition information of the second CSI, and the composition information is used for determining the bit number of the second CSI; wherein, the composition information of the second CSI includes: the method comprises the steps that indication information of non-zero broadband amplitude except broadband amplitude corresponding to the strongest combining coefficient in each data layer of N data layers is equal to a rank indication RI value determined by a terminal, wherein the RI is used for indicating the number of data layers, and N is an integer greater than or equal to 1; wherein, the indication information of the non-zero broadband amplitude is a bitmap, each 1 bit of the bitmap corresponds to the broadband amplitude of one merging coefficient, one data layer corresponds to one bitmap, and each 1 bit of each bitmap corresponds to the broadband amplitude of one merging coefficient; the bit number of the first CSI does not change along with the difference of the numbers of the non-zero broadband amplitudes except the broadband amplitude corresponding to the strongest combining coefficient of each data layer;

20. The communications apparatus of claim 19, wherein the indication of wideband amplitude is a bitmap, each 1 bit of the bitmap corresponding to a wideband amplitude of a combining coefficient;

21. The communications apparatus of claim 19, wherein the second CSI comprises:

22. The communications apparatus of any of claims 19 to 21, wherein the second CSI comprises:

23. The communications apparatus of claim 19, wherein the first CSI further comprises: and RI, the RI is used for indicating the number of data layers.

24. The communications apparatus of claim 19, wherein the first CSI or the second CSI comprises: twiddle factors and beam selection information.

25. The communications apparatus of claim 19, wherein the first CSI or the second CSI further comprises a channel quality indication, CQI, comprising a wideband CQI and/or a subband CQI for each subband.

26. The communications apparatus of any of claims 19-21, 23-25, wherein the number of bits of the first CSI does not vary with the number of data layers indicated by the RI determined by the terminal.

27. A communication device, comprising: the device comprises a processor, a memory and a transceiver, wherein the processor, the memory and the transceiver are connected through a bus; the processor is configured to read a program in the memory, and execute:

receiving first Channel State Information (CSI) sent by a terminal through the transceiver, wherein the first CSI comprises composition information of second CSI, and the composition information is used for determining the bit number of the second CSI; wherein, the composition information of the second CSI includes: the method comprises the steps that indication information of non-zero broadband amplitude except broadband amplitude corresponding to the strongest combining coefficient in each data layer of N data layers is equal to a rank indication RI value determined by the terminal, the RI is used for indicating the number of data layers, and N is an integer greater than or equal to 1; wherein, the indication information of the non-zero broadband amplitude is a bitmap, each 1 bit of the bitmap corresponds to the broadband amplitude of one merging coefficient, one data layer corresponds to one bitmap, and each 1 bit of each bitmap corresponds to the broadband amplitude of one merging coefficient; the bit number of the first CSI does not change along with the difference of the numbers of the non-zero broadband amplitudes except the broadband amplitude corresponding to the strongest combining coefficient of each data layer;

Determining the bit quantity of the second CSI according to the first CSI;

28. The communications apparatus of claim 27, wherein the indication of wideband amplitude is a bitmap, each 1 bit of the bitmap corresponding to a wideband amplitude of a combining coefficient;

29. The communications apparatus of claim 27, wherein the second CSI comprises:

30. The communications apparatus of any of claims 27 to 29, wherein the second CSI comprises:

31. The communications apparatus of claim 27, wherein the first CSI further comprises: and RI, the RI is used for indicating the number of data layers.

32. The communications apparatus of claim 27, wherein the first CSI or the second CSI comprises: twiddle factors and beam selection information.

33. The communications apparatus of claim 27, wherein the first CSI or the second CSI comprises a channel quality indication, CQI, comprising a wideband CQI and/or a subband CQI for each subband.

34. The communication apparatus according to any of claims 27 to 29, 31 to 33, wherein the number of bits of the first CSI does not vary with the number of data layers indicated by the RI determined by the terminal.

35. A computer storage medium storing computer executable instructions for causing the computer to perform the method of any one of claims 1 to 8.

36. A computer storage medium storing computer executable instructions for causing the computer to perform the method of any one of claims 9 to 16.