CN112187324B

CN112187324B - Channel state information feedback method and device

Info

Publication number: CN112187324B
Application number: CN201910604976.2A
Authority: CN
Inventors: 李辉; 高秋彬; 刘正宣
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2019-07-05
Filing date: 2019-07-05
Publication date: 2021-10-29
Anticipated expiration: 2039-07-05
Also published as: CN112187324A

Abstract

The application discloses a channel state information feedback method and device. In the application, a terminal carries out channel measurement to obtain CSI, wherein the CSI comprises at least one layer of nonzero coefficient set and nonzero coefficient position indication information; the terminal discards part of information in the CSI according to a CSI discarding rule and uplink resources allocated to the terminal; wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity; and the terminal sends the CSI of the discarded part of information to the base station.

Description

Channel state information feedback method and device

Technical Field

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

Background

In the NR Rel-15 system, a type ii (typeii) codebook is defined that supports both the rank1 codebook and the rank2 codebook based on the way in which beams within the orthogonal beam group are linearly combined.

For one subband, the rank1 codebook is expressed as:

for one subband, the rank2 codebook is expressed as:

wherein the content of the first and second substances,

l represents the number of orthogonal beams within the group,

representing orthogonal beams, using a 2D DFT (two-dimensional discrete Fourier transform)A interior transform) vector; r-0, 1 denotes the first and second polarization directions in the dual-polarized antenna array, l-0, 1 denotes a layer.

Representing the broadband amplitude coefficients acting on the beam i, the polarization direction r and the layer l in the beam group;

representing the subband amplitude coefficients acting on the beam i, the polarization direction r and the layer l in the beam group; c. C_r,l,iThe subband phase coefficients acting on the beam i, the polarization direction r and the layer l in the beam group are shown.

Since the number of codebook coefficients of Rank2 is about one time of the number of codebook coefficients of Rank1, the overhead of codebooks with different values of Rank Indication (RI) is very different. When the base station receives Channel State Information (CSI) fed back by the terminal, the base station cannot know the value of the RI before correctly decoding, and thus cannot determine the overhead of the CSI. In order to avoid that the base station cannot correctly perform CSI decoding due to overhead ambiguity, in Rel-15, a two-part structure is adopted for reporting Type II CSI. The first part of the CSI comprises: RI, a wideband Quality Indicator (CQI) corresponding to a first codeword (codeword), a differential CQI corresponding to the first codeword (codeword), the number of zero coefficients in layer one, and the number of zero coefficients in layer two; the second part of the CSI comprises: the antenna comprises a rotation factor, beam indication information, a strongest beam indication of a layer one, a wideband amplitude coefficient of a layer one, a strongest beam indication of a layer two, a wideband amplitude coefficient of a layer two, at least one of a subband phase and a subband amplitude coefficient of an even subband, and at least one of a subband phase and a subband amplitude coefficient of an odd subband. The overhead of the first part of the CSI is fixed and is irrelevant to the value of the RI, and the overhead of the second part of the CSI can be determined by the result of decoding of the first part.

Because the feedback of each subband includes both a subband phase coefficient and a subband amplitude coefficient, when the number of subbands is large, the feedback overhead required for feeding back coefficients of all subbands is huge, and for this reason, Precoding Matrix Indicator (PMI) information of a part of subbands may be discarded when the terminal reports CSI.

A low-overhead Type II codebook is defined in the NR Rel-16 system, the coefficient of each sub-band is compressed, and the compressed differential amplitude coefficient, phase coefficient and reference amplitude coefficient are all fed back to a base station. The Type II codebook defined in Rel-16 has no report amount of sub-band, and the discarding mechanism of Rel-15 cannot be reused. At present, for the codebook structure of Rel-16, a corresponding CSI discarding mechanism and a corresponding feedback method are not available.

Disclosure of Invention

The embodiment of the application provides a channel state information feedback method and device.

In a first aspect, a channel state information feedback method is provided, including: a terminal carries out channel measurement to obtain Channel State Information (CSI), wherein the CSI comprises at least one layer of nonzero coefficient set and nonzero coefficient position indication information; and the terminal discards partial information in the CSI according to a CSI discarding rule and uplink resources allocated to the terminal, and sends the CSI with the discarded partial information to the base station. Wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity.

In a possible implementation manner, the discarding part of information in the CSI includes:

discarding part or all of non-zero coefficients of at least one layer in the CSI; or, discarding part or all of the nonzero coefficient position indication information of at least one layer in the CSI; or discarding part or all of the non-zero coefficients of at least one layer in the CSI and part or all of the non-zero coefficient position indication information of at least one layer in the CSI.

In a possible implementation manner, the first granularity is a part or all of non-zero coefficient position indication information of one layer; alternatively, the first granularity is a part of non-zero coefficient position indication information of each layer.

In one possible implementation, the second granularity is a fraction of all non-zero coefficients in the CSI.

the terminal determines non-zero coefficient position indication information needing to be discarded in the CSI according to the first granularity, and discards the non-zero coefficient position indication information needing to be discarded; wherein the non-zero coefficient position indication information needing to be discarded comprises part or all of the non-zero coefficient position indication information of at least one layer;

the terminal compares the number of the nonzero coefficients corresponding to the nonzero coefficient position indication information needing to be discarded with the number of the nonzero coefficients of the second granularity;

if the former is greater than or equal to the latter, discarding part of coefficients in the nonzero coefficients corresponding to the nonzero coefficient position indication information needing to be discarded, wherein the number of the discarded nonzero coefficients is equal to the number of the nonzero coefficients corresponding to the second granularity or integral multiple of the number of the nonzero coefficients corresponding to the second granularity; or discarding all coefficients in the nonzero coefficients corresponding to the nonzero coefficient position indication information to be discarded, and filling N nonzero coefficients, wherein the value of N is the difference between the number of the nonzero coefficients corresponding to the nonzero coefficient position indication information to be discarded and the number of the nonzero coefficients of the second granularity;

if the former is smaller than the latter, all coefficients in the nonzero coefficients corresponding to the nonzero coefficient position indication information needing to be discarded are discarded, part of coefficients in the nonzero coefficients corresponding to the nonzero coefficient position indication information which does not need to be discarded are discarded, the nonzero coefficient position indication information which does not need to be discarded is updated according to the discarded nonzero coefficients, and the number of the discarded nonzero coefficients is equal to the number of the nonzero coefficients corresponding to the second granularity.

In one possible implementation manner, the method further includes: and the terminal discards at least one of the frequency domain base indication, the strongest coefficient index and the reference amplitude coefficient of at least one layer in the CSI.

In a second aspect, a channel state information feedback method is provided, including: a base station receives CSI sent by a terminal; the base station determines that part of information in the CSI sent by the terminal is discarded, and decodes the CSI according to a CSI discarding rule adopted by the terminal; wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity.

In one possible implementation, the CSI includes a first part of CSI or a first part of CSI and a second part of CSI, where the first part of CSI includes a rank indication RI and total number indication information of non-zero coefficients of all layers, and the second part of CSI includes all or part of non-zero coefficients of at least one layer and non-zero coefficient position indication information;

the base station decodes the CSI according to the CSI discarding rule adopted by the terminal, and the method comprises the following steps: the base station determines an information field contained in the second part of the CSI according to the first part of the CSI and a CSI discarding rule adopted by the terminal; and the base station decodes the second part of the CSI according to the information field contained in the second part of the CSI.

In one possible implementation, the decoding the second part of the CSI includes:

the base station determines the number of corresponding non-zero coefficients according to the non-zero coefficient position indication information of a first layer in the second part of the CSI, wherein the first layer is one of all layers contained in the CSI;

the base station compares the number of the nonzero coefficients indicated by the nonzero coefficient position indication information of the first layer with the number of the nonzero coefficients contained in the nonzero coefficient information field of the first layer;

if the former is smaller than the latter, the base station ignores the non-zero coefficient which is not corresponding to the non-zero coefficient position indication information of the first layer in the non-zero coefficient information domain of the first layer.

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

the processing module is used for carrying out channel measurement to obtain CSI, and the CSI comprises at least one layer of nonzero coefficient set and nonzero coefficient position indication information; and discarding part of information in the CSI according to a CSI discarding rule and the uplink resource allocated to the terminal. Wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity. And a sending module, configured to send the CSI with the discarded part of the information to the base station.

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

the receiving module is used for receiving the CSI sent by the terminal; the processing module is used for determining that part of information in the CSI sent by the terminal is discarded, and then decoding the CSI according to a CSI discarding rule adopted by the terminal; wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity.

In a fifth aspect, a communication apparatus is provided, including: a processor, memory, transceiver; the processor is configured to read computer instructions in the memory and execute the method according to any one of the above first aspects.

In a sixth aspect, a communication apparatus is provided, including: a processor, memory, transceiver; the processor is configured to read the computer instructions in the memory and execute the method according to any one of the above second aspects. :

in a seventh aspect, there is provided a computer-readable storage medium having stored thereon computer-executable instructions for causing the computer to perform the method of any of the above first aspects.

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

In the above embodiments of the present application, when performing CSI feedback, the terminal discards part of information in CSI according to a CSI discard rule and uplink resources allocated to the terminal, and sends the CSI with the discarded part of information to the base station. The CSI discarding rule is used for indicating that non-zero coefficient position indication information is discarded by taking the first granularity as a unit and/or non-zero coefficients are discarded by taking the second granularity as a unit, so that the reported CSI meets the requirement of uplink resources allocated to the terminal. Particularly, when the embodiment of the application is applied to an NR Rel-16 system, when the overhead of CSI to be reported exceeds the uplink resource allocated to the terminal, the embodiment of the application is adopted to discard and report part of CSI information, so that the reported CSI can be correctly decoded, and the performance of the system can be ensured.

Drawings

Fig. 1 is a schematic diagram of a CSI feedback process implemented on a terminal side according to an embodiment of the present application;

fig. 2 is a flow of discarding CSI according to an embodiment of the present disclosure;

fig. 3 is a schematic diagram of a CSI feedback process implemented by a base station according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a terminal according to 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 NR Rel-16 system, a low-overhead Type II codebook is defined, the coefficient of each sub-band is compressed, and the compressed coefficient is fed back to a base station. Taking rank1 as an example, the codebook can be expressed as shown in the following equation for all subbands:

wherein:

W₁the method comprises orthogonal combined beams, wherein the contained orthogonal combined beams are the same as a Type II codebook of a Rel-15 system.

Representing the compressed coefficient, where p_diff(i, j) represents a differential amplitude coefficient, q (i, j) represents a phase coefficient, p_refRepresenting a reference amplitude coefficient. If it is

Is located in the first polarization direction (i.e. the strongest amplitude coefficient of (b) is located in the first polarization direction

The first L rows) of the first row, the reference amplitude coefficient is located in the second polarization direction, as shown in the above expression; if it is

Is located in the second polarization direction (i.e. the strongest amplitude coefficient of (b) is located in the second polarization direction

The last L rows) of the array, the reference amplitude coefficient is located in the first polarization direction. The differential amplitude coefficient, the phase coefficient and the reference amplitude coefficient are all required to be fed back to the base station. And the terminal also needs to report the position of the strongest amplitude coefficient. The differential amplitude coefficient corresponding to the strongest amplitude coefficient is defined as 1, and the phase coefficient corresponding to the strongest amplitude coefficient is defined as 0, so that the differential amplitude coefficient and the phase coefficient corresponding to the strongest amplitude coefficient do not need to be reported. In addition, each layer is provided in view of further saving feedback overhead

The compression coefficients in (1) do not need to be reported completely, and only the nonzero coefficients in (1) can be reported. For Rank1 and Rank2, the base station configures the upper limit of the number of nonzero coefficients reported by each layer to be K0. Since all the compression coefficients do not need to be reported, the position of the reported nonzero coefficient needs to be indicated for each layer.

W_fRepresenting compressed basis vectors, comprising M basis vectors, each of length N₃，N₃Determined by the number of CQI subbands configured by the system.

Taking rank2 as an example, the Type II codebook in the NR Rel-16 system has the first layer precoding expressed as follows:

the second layer precoding is represented by the following equation:

wherein, W₁The method comprises the steps of including orthogonal combined beams, wherein the number of the included orthogonal beams is 2L; w_f,0A base vector, W, representing layer one_f,1A base vector, W, representing layer two_f,0And W_f,1Respectively comprises M base vectors;

represents the layer-one corresponding compressed coefficients,

representing the compressed coefficients corresponding to layer two,

and

each of which contains 2L x M coefficients.

In other cases of rank, the expression of the Type II codebook in the NR Rel-16 system may be derived by referring to the expression of rank ═ 2, which is not described herein again.

According to the codebook structure, when the terminal reports the CSI, the CSI cost has larger difference corresponding to different RI values. If rank is 1, reporting K0 nonzero coefficients at most, and reporting position indication information (for example, using a bitmap indication) of the K0 nonzero coefficients at most; when rank is 2, report 2 × K0 nonzero coefficients at most, and report position indication information of the nonzero coefficients of each layer (each layer uses a bitmap indication). Thus, the PMI overhead when Rank2 is close to twice that when Rank 1. Because the base station cannot predict the RI value fed back by the terminal in advance, if the uplink resource is allocated according to the overhead of rank1, and the terminal determines rank2 and reports CSI according to the RI value, the overhead of the CSI to be reported exceeds the uplink resource allocated by the base station, and therefore part of PMI information needs to be discarded in the reported CSI, so as to ensure that the base station can correctly receive and decode the CSI reported by the terminal.

The embodiment of the application provides a CSI feedback method, and under the condition that uplink resources allocated to a terminal are not enough to feed back all information of CSI, part of information in the CSI is discarded and then reported, so that correct decoding of the CSI can be guaranteed, and the performance of a system can also be guaranteed. The embodiment of the application is applicable to a Rel-16 system and carries out CSI feedback based on the type II codebook structure.

The embodiment of the application can be applied to the NR Rel-16 system or the evolution system thereof, or other systems needing to discard the CSI.

Some technical terms in the embodiments of the present application will be described first.

In this embodiment, a "terminal," also referred to as User Equipment (UE), a Mobile Station (MS), a Mobile Terminal (MT), etc., is a device that provides voice and/or data connectivity to a user, for example, a handheld device, a vehicle-mounted device, etc. with a wireless connection function. Currently, some examples of terminals are: a mobile phone (mobile phone), a tablet computer, a notebook computer, a palm top computer, a Mobile Internet Device (MID), a wearable device, a Virtual Reality (VR) device, an Augmented Reality (AR) device, a wireless terminal in industrial control (industrial control), a wireless terminal in self driving (self driving), a wireless terminal in remote surgery (remote medical supply), a wireless terminal in smart grid (smart grid), a wireless terminal in transportation safety (smart security), a wireless terminal in city (smart city), a wireless terminal in home (smart home), and the like.

The "network device" in the embodiment of the present application may be a RAN node or a base station. The RAN is the part of the network that accesses the terminal to the wireless network. A 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 gbb, a Transmission Reception Point (TRP), an evolved Node B (eNB), a Radio Network Controller (RNC), a Node B (NB), a Base Station Controller (BSC), a Base Transceiver Station (BTS), a home base station (e.g., home evolved Node B, or home Node B, HNB), a Base Band Unit (BBU), or a wireless fidelity (Wifi) Access Point (AP), etc. In addition, in one network configuration, the RAN may include a Centralized Unit (CU) node and a Distributed Unit (DU) node.

The codebook in the embodiment of the present application is a matrix, for example, the codebook is a precoding matrix.

The "beams," i.e., vectors, in the embodiments of the present application may be referred to as beam vectors or otherwise named.

The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

In the embodiment of the present application, a CSI discard rule may be predefined, and the rule may be known to the terminal and the base station. Different terminals may use the same CSI drop rule or different CSI drop rules.

The CSI discard rule is used to instruct the terminal to discard information in the CSI, for example, how many non-zero coefficients to discard may be defined, or which layers of non-zero coefficients to discard may be defined. The terminal can discard part of the information in the CSI according to the CSI discarding rule, so that the terminal can meet the requirement of uplink resources allocated to the terminal. The base station can correctly decode the CSI reported by the terminal and discarded with partial information according to the CSI discarding rule adopted by the terminal.

Wherein the CSI discard rule may be specified for a one-time discard operation. When the terminal discards the CSI, the terminal can repeatedly execute the discarding operation for many times according to the CSI discarding rule until the requirement of the uplink resource is met, or can determine all information to be discarded at one time according to the CSI discarding rule and the uplink resource allocated to the terminal and perform the discarding operation so as to meet the requirement of the uplink resource.

Specifically, the CSI discard rule is used to indicate that non-zero coefficient position indication information is discarded in units of a first granularity; or, the CSI discard rule is configured to instruct to discard non-zero coefficients in units of a second granularity; or, the CSI discard rule is configured to instruct to discard non-zero coefficient position indication information in units of a first granularity, and discard non-zero coefficients in units of a second granularity.

Optionally, in some embodiments, the first granularity is a part or all of non-zero coefficient position indication information of one layer. For example, the first granularity may be all bits of a non-zero coefficient position indication sequence (bitmap) of a layer, i.e., the CSI discard rule specifies discarding non-zero coefficient position indication sequences (bitmaps) of a layer at a time. As another example, the first granularity may be half the number of bits of a non-zero coefficient position indication sequence (bitmap) of a layer, i.e., the CSI discard rule specifies discarding half the number of bits of a non-zero coefficient position indication sequence (bitmap) of a layer at a time. Specifically, bits at which positions are discarded and bits at which positions are reserved may be specified by the CSI discard rule or agreed by the system, which is not limited in the embodiment of the present application.

Optionally, in other embodiments, the first granularity is a portion of non-zero coefficient position indication information for each layer. For example, the first granularity is half the number of bits of the non-zero coefficient position indication sequence (bitmap) of each layer, i.e., the CSI discard rule specifies discarding half the number of bits of the non-zero coefficient position indication sequence (bitmap) of each layer at a time. Specifically, bits at which positions are discarded and bits at which positions are reserved may be specified by the CSI discard rule or agreed by the system, which is not limited in the embodiment of the present application.

Optionally, the second granularity is a fraction of all non-zero coefficients in the CSI. For example, the second particle size is (K)_Tthe/RI) non-zero coefficients, i.e. the CSI discard rule specifies a discard (K)_T/RI) non-zero coefficients, wherein K_TAnd the sum of the number of the nonzero coefficients of all the layers is represented, and RI represents a rank value. As another example, the second particle size is (K)_T2) non-zero coefficients, i.e. the CSI discard rule specifies a discard (K)_T/2) non-zero coefficients, where K_TRepresenting the sum of the number of non-zero coefficients for all layers.

Referring to fig. 1, a schematic diagram of a CSI feedback process implemented on a terminal side according to an embodiment of the present application is provided, where the process may include:

s101: and the terminal carries out channel measurement to obtain CSI.

Wherein the CSI comprises a non-zero coefficient set of at least one layer and non-zero coefficient position indication information. In specific implementation, according to the value of the RI determined by the terminal, the CSI may include feedback information of a corresponding layer. For example, if RI is 2, the CSI includes a nonzero coefficient set and nonzero coefficient position indication sequence (bitmap) information corresponding to each of the layer one and the layer two, and if RI is 3, the CSI includes a nonzero coefficient set and nonzero coefficient position indication sequence (bitmap) corresponding to each of the layer one, the layer two, and the layer three.

The non-zero coefficient set of a layer may include a non-zero amplitude coefficient set and a non-zero phase coefficient set of the layer, where the amplitude coefficient set includes a differential amplitude coefficient and a reference amplitude coefficient.

All information of the CSI can be reported in two parts, that is, the CSI may include a first part of the CSI and a second part of the CSI. The first part of the CSI comprises total number indication information of nonzero coefficients of all layers, and the second part of the CSI comprises the nonzero coefficients and nonzero coefficient position indication information which correspond to all the layers respectively.

Specifically, for full CSI, the first part of CSI may include the following information:

RI；

a wideband CQI;

differential CQI, if a plurality of sub-bands exist, each sub-band corresponds to one differential CQI;

a total number of non-zero coefficients indicating a sum of the numbers of non-zero coefficients of all layers.

For full CSI, the second part of the CSI may comprise for each layer respective specific information.

Taking the ith layer as an example, the information of the ith layer in the second part of CSI may include:

the frequency domain base indication of the ith layer indicates the frequency domain base vector used for constructing the precoding matrix of the layer;

the non-zero coefficient position indication information of the ith layer indicates the position of the non-zero coefficient of the layer in a coefficient matrix corresponding to the layer for constructing a precoding matrix;

the strongest coefficient index of the ith layer indicates the position of the strongest amplitude coefficient of the ith layer in a coefficient matrix corresponding to the ith layer for constructing a precoding matrix;

a reference amplitude coefficient for the ith layer;

the differential amplitude coefficient of the ith layer;

phase amplitude coefficient of the ith layer.

For layer one, in the second part of CSI, the information corresponding to layer one may further include a spatial base indicator and a twiddle factor indicator.

S102: and the terminal discards part of information in the CSI according to the CSI discarding rule and the uplink resource allocated to the terminal.

Optionally, the first part of the CSI is not discarded, and part or all of the information in the second part of the CSI may be discarded. Specifically, in some embodiments, the discarded partial CSI information includes some or all of the non-zero coefficients of at least one layer of CSI. In some further embodiments, the discarded partial CSI information comprises partial or all non-zero coefficient position indication information of at least one layer of CSI. In some other embodiments, the discarded partial CSI information includes some or all non-zero coefficients of at least one layer of CSI and some or all non-zero coefficient position indication information of at least one layer of CSI.

S103: and the terminal sends the CSI with the discarded part of information to the base station.

Optionally, in some embodiments, one implementation of S102 in fig. 1 may be as shown in fig. 2.

Referring to fig. 2, a flow for discarding CSI provided in an embodiment of the present application is exemplarily shown. As shown, the process may include:

s201: the terminal determines non-zero coefficient position indication information needing to be discarded in the CSI according to the first granularity in the CSI discarding rule, and discards the non-zero coefficient position indication information needing to be discarded.

Wherein the non-zero coefficient position indication information to be discarded includes part or all of the non-zero coefficient position indication information of at least one layer.

S202: and the terminal compares the number of the nonzero coefficients corresponding to the nonzero coefficient position indication information needing to be discarded with the number of the nonzero coefficients of the second granularity, and if the number of the nonzero coefficients is larger than or equal to the number of the nonzero coefficients of the second granularity, the step is switched to S203, otherwise, the step is switched to S204.

S203: and the terminal discards part of the coefficients in the nonzero coefficients corresponding to the nonzero coefficient position indication information needing to be discarded, wherein the number of the discarded nonzero coefficients is equal to the number of the nonzero coefficients corresponding to the second granularity.

In this step, the number of nonzero coefficients corresponding to the nonzero coefficient position indication information that needs to be discarded is greater than or equal to the number of nonzero coefficients of the second granularity, which indicates that the number of nonzero coefficients that needs to be discarded is greater than or equal to the number of nonzero coefficients of one discarding operation indicated by the CSI discarding rule, so that part of the nonzero coefficients corresponding to the nonzero coefficient position indication information that needs to be discarded is discarded, and the number of discarded nonzero coefficients is equal to the specification of the CSI discarding rule. All the coefficients in the nonzero coefficients corresponding to the nonzero coefficient position indication information needing to be discarded can be discarded, and N nonzero coefficients are filled. And the value of N is the difference between the number of the nonzero coefficients corresponding to the nonzero coefficient position indication information needing to be discarded and the number of the nonzero coefficients of the second granularity.

Taking half the number of bits in a non-zero coefficient position indication sequence (bitmap) with a first granularity as one layer and T non-zero coefficients with a second granularity as an example, in S202, a terminal determines that the number of non-zero coefficients corresponding to half the number of bits in the non-zero coefficient position indication sequence (bitmap) of an ith layer is S, and S is greater than or equal to T, then the terminal discards all the non-zero coefficients corresponding to the discarded non-zero coefficient position indication sequence (bitmap) of the ith layer, and then supplements (S-T) non-zero coefficients to CSI to be reported. Wherein the supplemented (S-T) non-zero coefficients may be selected from the discarded non-zero coefficients. Since the supplemented (S-T) non-zero coefficients can be ignored when the base station decodes the CSI, the supplemented (S-T) non-zero coefficients may also be arbitrary, and the embodiment of the present application is not limited.

Still taking half the number of bits in a non-zero coefficient position indication sequence (bitmap) with a first granularity as one layer and T non-zero coefficients with a second granularity as an example, in S202, the terminal determines that the number of non-zero coefficients corresponding to half the number of bits in the non-zero coefficient position indication sequence (bitmap) of the ith layer is S, S is greater than or equal to T, the terminal discards the T non-zero coefficients in the non-zero coefficients corresponding to the discarded non-zero coefficient position indication sequence (bitmap) of the ith layer, and the remaining (S-T) non-zero coefficients are retained in CSI for reporting.

S204: the terminal discards all the coefficients in the nonzero coefficients corresponding to the nonzero coefficient position indication information which needs to be discarded, discards part of the coefficients in the nonzero coefficients corresponding to the nonzero coefficient position indication information which does not need to be discarded, and updates the nonzero coefficient position indication information which does not need to be discarded according to the discarded nonzero coefficients, wherein the number of the discarded nonzero coefficients is equal to the number of the nonzero coefficients corresponding to the second granularity.

In this step, the number of nonzero coefficients corresponding to the nonzero coefficient position indication information that needs to be discarded is smaller than the number of nonzero coefficients of the second granularity, which indicates that the number of nonzero coefficients that needs to be discarded is smaller than the number of nonzero coefficients of one discarding operation indicated by the CSI discarding rule, so that after all nonzero coefficients corresponding to the nonzero coefficient position indication information that needs to be discarded are discarded, part of nonzero coefficients need to be discarded additionally, and the number of discarded nonzero coefficients is equal to the specification of the CSI discarding rule.

Taking half the number of bits in a non-zero coefficient position indication sequence (bitmap) with a first granularity as one layer and T non-zero coefficients with a second granularity as an example, in S202, the terminal determines that the number of non-zero coefficients corresponding to half the number of bits in the non-zero coefficient position indication sequence (bitmap) of the i-th layer is S, and S is smaller than T, then the terminal discards all the non-zero coefficients corresponding to the discarded non-zero coefficient position indication sequence (bitmap) of the i-th layer, discards (T-S) coefficients in all the non-zero coefficients corresponding to bits that are not discarded in the non-zero coefficient position indication sequence (bitmap) of the i-th layer, and updates bit values in the non-zero coefficient position indication sequences corresponding to the (T-S) coefficients to zero coefficient indication values.

Optionally, to further reduce CSI feedback overhead, the terminal may also discard at least one of the frequency-domain basis indicator, the strongest coefficient index, and the reference amplitude coefficient of at least one layer of CSI.

Optionally, in some embodiments, the terminal repeatedly performs the discarding operation according to the CSI discarding rule until the CSI meets the requirement of the uplink resource, and finally reports the CSI obtained after the discarding operation is performed for multiple times, and in other embodiments, the terminal determines, at a time, CSI information that needs to be discarded according to the CSI discarding rule and the uplink resource allocated to the terminal, so that the CSI of the discarded part of information meets the requirement of the uplink resource, performs the discarding operation according to the determined CSI information that needs to be discarded, and reports the CSI of the discarded part of information.

It should be noted that, in the case that the terminal performs the CSI discard operation for multiple times, according to the flow shown in fig. 2, S203 may be performed multiple times, and each time S203 is performed, a corresponding number of non-zero coefficients are discarded according to the second granularity, so that the number of the discarded non-zero coefficients is equal to an integer multiple of the number of non-zero coefficients corresponding to the second granularity.

Referring to fig. 3, a schematic diagram of a CSI feedback process implemented at a base station side according to an embodiment of the present application is provided, where the process may include:

s301: and the base station receives the CSI sent by the terminal.

If the uplink resource of the terminal meets the feedback overhead of the CSI, the terminal may report the CSI after obtaining the CSI through channel measurement, and if the uplink resource of the terminal cannot meet the feedback overhead of the CSI, the terminal may discard part of the information in the CSI obtained by measurement in the manner described in the foregoing embodiment of the present application, and report the CSI with the discarded part of the information.

For the method for the terminal to discard CSI, reference may be made to the description of the foregoing embodiments, and the description is not repeated here.

S302: and the base station determines whether part of information in the CSI sent by the terminal is discarded, if so, the step is shifted to S303, and if not, the step is shifted to S304.

In this step, the base station may determine whether part of information in the CSI reported by the terminal is discarded according to the CSI reported by the terminal and the uplink resource allocated to the terminal by the base station.

Specifically, the first part of the CSI generally is not discarded, where the first part of the CSI includes RI (the value of RI is equal to the number of layers) and information indicating the total number of nonzero coefficients of all layers, and in the second part of the CSI, the number of bits in the frequency domain base indication field, the nonzero coefficient position indication information field, and the strongest coefficient index information field in each layer is fixed, so that the base station may determine the number of bits occupied by the nonzero coefficients in all layers according to the total number of nonzero coefficients of all layers indicated by the first part of the CSI, and may further determine the number of bits of the complete CSI (the complete CSI refers to CSI that is not subjected to discarding operation), that is, may determine the resource overhead of the complete CSI. And if the resource overhead of the CSI reported in the uplink resource is less than the determined resource overhead of the complete CSI, indicating that the terminal side discards the CSI.

S303: and the base station decodes the CSI according to the CSI discarding rule adopted by the terminal.

For the description of the CSI dropping rule, reference may be made to the foregoing embodiments, and the description is not repeated here.

In this step, the base station may determine, according to the CSI discard rule, an information field included in the second part of the CSI reported by the terminal (that is, the information field of which layer the second part of the CSI includes, or the information field included in a layer, or the number of bits occupied by one information field), and then decode the second part of the CSI according to the information field included in the determined second part.

For example, the CSI discard rule employed by the terminal specifies discarding one layer of the position indication sequence (bitmap) of non-zero coefficients at a time, and discarding K at a time_TThe base station may determine, according to the CSI discard rule, that the second part of the CSI does not include a non-zero position indication sequence (bitmap) field of layer two, and the number of non-zero coefficients included in the non-zero coefficient information field of layer two is smaller than that in a normal case (i.e., a case where the discard operation is not performed) by K, if RI in the first part of the CSI reported by the terminal is 2_Tand/RI.

As another example, the CSI discard rule employed by the terminal specifies: for non-zero coefficient position indication sequences (bitmaps), discarding half of the bits in each layer including all layers at once indicates the bitmap, and for non-zero coefficients, discarding K at once_T2 non-zero coefficients. If the RI in the first part of the CSI reported by the terminal is 2, the base station may determine the CSI according to the CSI discard ruleThe second part includes information fields of layer one and layer two, but the length of the non-zero position indication sequence (bitmap) fields of layer one and layer two is reduced by half compared with the normal length (i.e. the length without discarding operation), and the number of non-zero coefficients included in the non-zero coefficient information fields of layer one and layer two is reduced by K compared with the normal case (i.e. without discarding operation)_TAnd 2, the number of the cells is increased.

Optionally, when the base station decodes the received CSI, the base station determines the number of corresponding non-zero coefficients according to the non-zero coefficient position indication information of the ith layer in the second part of the CSI; the base station compares the number of the nonzero coefficients indicated by the nonzero coefficient position indication information of the ith layer with the number of the nonzero coefficients contained in the nonzero coefficient information field of the ith layer; if the former is smaller than the latter, it indicates that the non-zero coefficient information field of the i-th layer contains redundant non-zero coefficients, which may be supplemented to meet the requirement of the number of non-zero coefficients specified by the CSI discard rule when the terminal performs CSI discard, and the base station may ignore the non-zero coefficients (i.e., the non-zero coefficients not corresponding to the non-zero coefficient position indication information of the i-th layer) in the non-zero coefficient information field of the i-th layer, that is, not perform decoding. If the former is equal to the latter, the non-zero coefficient in the non-zero coefficient information field of the i-th layer is decoded.

Wherein the non-zero coefficient information field may include a differential amplitude coefficient information field and a phase coefficient information field.

S304: the base station directly decodes the received CSI.

Specific examples of several scenarios are given below, and are described below, according to one or a combination of the above embodiments of the present application.

Example 1

The precoding matrix uses the same 2L beams (spatial basis) for each layer according to the definition of the Type II codebook. For layer i, M is used_iThe frequency domain basis vectors form a set of compressed basis vectors. Maximum reported K0 ═ 2L × M per layer₁And 2K0 non-zero coefficients are reported by all layers at most.

For the Type II codebook of layer i, its precoding is expressed as:

wherein, W₁In which 2L space-domain basis vectors, W_f,iComprising M_iA number of frequency-domain basis vectors,

comprising 2L M_iA coefficient.

The CSI discarding rule is to discard in sequence according to layers, wherein the first granularity is a non-zero coefficient position indication sequence (bitmap) of one layer, and the second granularity is K_Tand/RI nonzero coefficients. That is, for non-zero coefficient position indication sequences (bitmaps), one layer of bitmaps are discarded at a time, and for non-zero coefficients, K is discarded at a time_Tand/RI nonzero coefficients. Wherein, K_TAnd the sum of the number of the nonzero coefficients of all the layers is represented, and RI represents a rank value.

If the terminal determines that RI is 3, the determined complete CSI information is as follows:

the first part of the CSI, as shown below, includes:

wherein, K_NZ1Number of non-zero coefficients, K, representing layer one_NZ2Number of non-zero coefficients, K, representing layer two_NZ3Indicating the number of non-zero coefficients for layer three. N is a radical of_sb＝N₃。

The second part of the CSI, as shown below, comprises:

wherein the non-zero coefficient position indication for the ith layer adopts a size of 2LM_iThe bitmap of the bit indicates.

When the uplink channel resources allocated by the base station are insufficient, the CSI of the first part is reported normally (the content contained in the CSI is as described above). In the second part, the non-zero coefficient position indication bitmap (total 2 LM) of layer three is discarded first₃One bit) and discards the non-zero coefficients (including the differential amplitude coefficients and the phase coefficients) of layer three. Wherein the number of the nonzero coefficients of the layer three is K_NZ3。

The number K of non-zero coefficients of the layer three of the terminal_NZ3With a second granularity K in the CSI discard rule_TThe RI is compared, and the following steps are executed according to the comparison result:

if K_NZ3Greater than or equal to K_TOne way is to divide K of layer three_NZ3All non-zero coefficients are discarded. At this time, the number of the discarded nonzero coefficients exceeds K_TRI, to ensure that the number of non-zero coefficients discarded at each time meets the requirements of the CSI discard rule (i.e. K is discarded at each time)_TRI non-zero coefficients), then the second part of the CSI needs to be supplemented (K)_NZ3-K_T/RI) non-zero coefficients. The added KNZ3-KT/RI can be of any value and can also be K of layer three_NZ3The non-zero coefficients are selected at will without limitation, so that the base station can determine the size of the second part of the CSI according to the CSI discarding rule, and the CSI can be decoded correctly. Another way is to combine K of layer three_NZ3Of a non-zero coefficient of (K)_T/RI) non-zero coefficients are discarded and the remaining non-zero coefficients are retained.

If K_NZ3Less than K_T/RI, then K of layer three_NZ3All non-zero coefficients are discarded. The number of the discarded nonzero coefficients does not reach K specified by the CSI discarding rule_TRI, the non-zero coefficients of some other layer need to be discarded(K_T/RI-K_NZ3) And (4) respectively. And, the discarded (K) is in a non-zero coefficient position indication sequence (bitmap) of the corresponding layer_T/RI-K_NZ3) And the bit position corresponding to the nonzero coefficient needs to be updated and is updated to be the zero coefficient indication. For example, K_T/RI-K_NZ3When the number of the non-zero coefficients of the layer two is 5, 5 non-zero coefficients are discarded, and in the non-zero coefficient position indication bitmap of the layer two, the bit value of the position of the 5 non-zero coefficients is changed from 1 to 0. Indicating that these 5 positions have no non-zero coefficients to report.

Since one granularity discards the non-zero coefficient position indication of a layer, the codebook parameters of this layer are already unusable. Thus other parameters of this layer including frequency domain basis indication, strongest coefficient index, reference amplitude coefficient can be discarded.

Above is a granularity CSI discard process. And if the CSI after the primary discarding is finished meets the requirement of the uplink resource allocated to the terminal, the terminal performs CSI feedback. Otherwise, continuing to perform the CSI discarding process again according to the above manner until the CSI size meets the uplink resource requirement.

The other mode is that the terminal determines to discard the CSI with multiple granularities at one time according to the uplink resources allocated by the system and the complete CSI overhead. If the non-zero coefficient position indication bitmap of two layers is discarded, 2K is discarded_TAfter the/RI nonzero coefficients meet the requirement of uplink resources, the uplink resources are discarded once. The non-zero coefficient positions of the two layers indicate bitmap and 2K is discarded_TAnd after the/RI nonzero coefficients, feeding back the CSI processed by the discarding operation.

On the base station side, the base station may determine whether the CSI reported by the terminal is discarded according to the first part of the CSI reported by the terminal and the uplink channel resource allocated to the terminal. If part of the information in the CSI reported by the terminal is discarded, the base station can determine the size of the second part of the CSI reported by the terminal, the information field contained in the second part of the CSI and the part needing to be decoded according to the CSI discarding rule, so that correct decoding is performed.

Example two

According to the definition of Type II codebook, for each layer, preThe coding matrix uses the same 2L beams (spatial basis). For layer i, M is used_iThe frequency domain basis vectors form a set of compressed basis vectors. Report a maximum of K0 ═ 2L M per layer₁And 2K0 non-zero coefficients are reported by all layers at most.

For the Type II codebook of layer i, its precoding is expressed as:

comprising 2L M_iA coefficient.

The CSI discard rule is to discard half of the frequency domain basis vectors at a time, wherein the first granularity is half bits in a non-zero coefficient position indication sequence (bitmap) of each layer, and the second granularity is K_T2 non-zero coefficients. That is, for a non-zero coefficient position indication sequence (bitmap), one-half of the bits in the bitmap are discarded at a time for non-zero coefficient position indication sequences for each layer including all layers, and for non-zero coefficients, K is discarded at a time_T2 non-zero coefficients. Wherein, K_TRepresenting the sum of the number of non-zero coefficients for all layers.

the first part of the CSI, as shown below, includes:

The second part of the CSI, as shown below, includes:

When the uplink channel resources allocated by the base station are insufficient, the CSI of the first part is reported normally (the content contained in the CSI is as described above). In the second part, half of the non-zero coefficient position indication bits of each layer are discarded first. I.e. layer one discard LM₁Bit map of bits, layer two discard LM₂Bit map of bits, layer three discard LM₃The bitmap of the bit. LM in indication of discarded non-zero coefficient positions in layer one, layer two and layer three₁、LM₂And LM₃The total number of the nonzero coefficients corresponding to the bits is K_halfTerminal will K_halfWith a second granularity K in the CSI discard rule_TAnd/2, comparing, and executing the following steps according to the comparison result:

if K_halfGreater than or equal to K_TOne way is to indicate the discarded non-zero coefficient positions in layer one, layer two and layer three for the corresponding K_halfAll non-zero coefficients are discarded. At this time, the number of the discarded nonzero coefficients exceeds K_T2, in order to ensure that the number of non-zero coefficients discarded at each time meets the requirements of the CSI discarding rule (i.e. each time K is reduced)_T2 nonzero coefficients), then (Khalf-KT/2) nonzero coefficients need to be supplemented in the CSI second part, and the supplemented Khalf-KT/2 can be arbitrarily set, which is not limited herein. The size of the CSI second part can be determined by the base station according to the CSI discarding rule, so that the CSI can be correctly decoded. In additionOne way is to indicate the discarded non-zero coefficient positions in layer one, layer two and layer three as corresponding to K_halfK of non-zero coefficients_TThe/2 non-zero coefficients are discarded, and the remaining non-zero coefficients are retained and still reported.

If K_halfLess than K_T2, indicating the discarded non-zero coefficient positions in the first layer, the second layer and the third layer to the corresponding K_halfAll non-zero coefficients are discarded. The number of the discarded nonzero coefficients does not reach K specified by the CSI discarding rule_T2, it needs to determine (K) additionally in the non-zero coefficient corresponding to the non-zero coefficient position indication which is not discarded_T/2-K_half) One non-zero coefficient is discarded. And, in these extra discarded non-zero coefficient position indication sequences (bitmaps), the corresponding (K)_T/2-K_half) And the bit position corresponding to the nonzero coefficient needs to be updated and is updated to be the zero coefficient indication. For example, K_T/2-K_halfLM not discarded according to layer three when 5₃The bitmap of the bit indicates that 5 non-zero coefficients are selected for discarding. Meanwhile, in the non-discarded bitmap, the bit value of the position of the 5 nonzero coefficients is changed from 1 to 0, which indicates that no nonzero coefficient is reported in the 5 positions. Alternatively, LM's that are not discarded according to layer one, layer two and layer three₁、LM₂And LM₃The bitmap of the bit indicates that 1 non-zero coefficient is selected in layer one, 2 non-zero coefficients are selected in layer two, and 2 non-zero coefficients are selected in layer three to be discarded. Correspondingly, in the respective non-discarded bitmap, the bit value of the position of the discarded non-zero coefficient is changed from 1 to 0, which indicates that no non-zero coefficient is reported in the corresponding position.

Above is a granularity CSI discard process. And if the size of the CSI after the primary discarding meets the requirement of the uplink resource allocated to the terminal, the terminal reports the CSI. Otherwise, continuing to perform the CSI discarding process again according to the above manner until the CSI size meets the uplink resource requirement.

And on the base station side, the base station judges whether the CSI reported by the terminal is discarded or not according to the first part of the CSI reported by the terminal and the uplink channel resource allocated to the terminal. If part of the information in the CSI reported by the terminal is discarded, the base station can determine the size of the second part of the CSI reported by the terminal, the information field contained in the second part of the CSI and the part needing to be decoded according to the CSI discarding rule, so that correct decoding is performed.

Example three

The precoding matrix uses the same 2L beams (spatial basis) for each layer according to the definition of the Type II codebook. For layer i, M is used_iThe frequency domain basis vectors form a set of compressed basis vectors. Report a maximum of K0 ═ 2L M per layer₁And 2K0 non-zero coefficients are reported by all layers at most.

For the Type II codebook of layer i, its precoding is expressed as:

comprising 2L M_iA coefficient.

The CSI discard rule is to discard K0 non-zero coefficients at a time, while discarding all codebook parameters for one layer. That is, the first granularity in the CSI discard rule is a non-zero coefficient position indication sequence (bitmap) of one layer, and the second granularity is K0 non-zero coefficients.

If the terminal determines that RI is 2, the determined complete CSI information is as follows:

the first part of the CSI is as follows, including:

wherein, K_NZ1Number of non-zero coefficients, K, representing layer one_NZ2Indicating the number of non-zero coefficients for layer two. N is a radical of_sb＝N₃。

The second part of the CSI, as shown below, includes:

When the uplink channel resource allocated to the terminal by the base station is insufficient, the CSI of the first part is reported normally (the content contained in the CSI is as described above). In the second part, the frequency domain base indication, the non-zero coefficient position indication, the strongest coefficient index and the reference amplitude coefficient of layer two are discarded. According to the definition of Type II codebook, there is K_NZ2K0, i.e., the number of non-zero coefficients of layer two is less than or equal to the second granularity specified by the CSI discard rule, it is necessary to put K of layer two_NZ2The non-zero coefficients are all discarded (including the differential amplitude coefficients and the phase coefficients). In addition, layer one (K0-K)_NZ2) The non-zero coefficients are also discarded, with the corresponding (K0-K) in the indication of the position of the non-zero coefficient in layer one_NZ2) And changing the bit of each position from 1 to 0 to indicate that no non-zero coefficient is reported at the corresponding position.

And if the size of the CSI after the discarding for the previous time meets the uplink resource allocated by the system, the terminal reports the CSI. Otherwise, the second part of CSI is discarded completely, and only the first part of CSI is reported.

Example four

For the Type II codebook of layer i, its precoding is expressed as:

comprising 2L M_iA coefficient.

The CSI discard rule is to discard all codebook parameters except for non-zero coefficients one layer at a time, wherein the first granularity is a non-zero coefficient position indication sequence (bitmap) of one layer. Specifically, the CSI discard rule specifies that all codebook parameters of one layer except for non-zero coefficients are discarded for the first time, and K0 non-zero coefficients are discarded for the second time. And discarding in sequence until the nonzero coefficients are all discarded, or until the nonzero coefficient position indication sequences (bitmaps) of all layers are all discarded, and at the moment, the second part of the CSI does not need to be reported.

the first part of the CSI, as shown below, includes:

wherein, K_NZ1Number of non-zero coefficients, K, representing layer one_NZ2Indicating the number of non-zero coefficients for layer two. And has N_sb＝N₃。

The second part of the CSI, as shown below, includes:

wherein the indication of the position of the non-zero coefficient for the i-th layer uses a size of 2LM_iThe bitmap of the bit indicates.

When the uplink channel resources allocated by the base station are insufficient, the CSI of the first part is reported normally (the content contained in the CSI is as described above). In the second part, the frequency domain base indication, the non-zero coefficient position indication, the strongest coefficient index and the reference amplitude coefficient of layer two are discarded. And if the size of the CSI after the discarding for the previous time meets the uplink resource allocated by the system, the terminal reports the CSI. Otherwise, according to the definition of Type II codebook, there is K_NZ2K0, that is, the number of non-zero coefficients of layer two is less than or equal to the number of non-zero coefficients of layer two, which is specified by the system, and at most K0 non-zero coefficients are discarded, so that K of layer two needs to be reduced_NZ2The non-zero coefficients are all discarded (including the differential amplitude coefficients and the phase coefficients). In addition, layer one (K0-K)_NZ2) The non-zero coefficients are also discarded, with the corresponding (K0-K) in the indication of the position of the non-zero coefficient in layer one_NZ2) And changing the bit of each position from 1 to 0 to indicate that no non-zero coefficient is reported at the corresponding position.

And if the CSI after the second discarding meets the uplink resource allocated by the system, the terminal reports the CSI. Otherwise, the frequency domain base indication, the non-zero coefficient position indication, the strongest coefficient index and the reference amplitude coefficient of layer one are continuously discarded. Since all non-zero coefficient position indications at this time have been discarded, the second-part CSI does not need to be reported.

Based on the same technical concept, the embodiment of the invention also provides a terminal and a base station, which can be respectively applied to the embodiments.

Fig. 4 is a schematic structural diagram of a terminal according to an embodiment of the present invention. As shown, the terminal may include: a processing module 401 and a sending module 402, wherein:

a processing module 301, configured to perform channel measurement to obtain CSI, where the CSI includes at least one layer of non-zero coefficient set and non-zero coefficient position indication information; and discarding part of information in the CSI according to a CSI discarding rule and uplink resources allocated to the terminal; wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity;

a sending module 302, configured to send the CSI with the discarded part of the information to the base station.

The functions of the modules in the terminal can be referred to the description of the functions implemented by the terminal in the foregoing embodiments, and are not repeated here.

Fig. 5 is a schematic structural diagram of a base station according to an embodiment of the present invention. As shown, the base station may include: a receiving module 501 and a processing module 502, wherein:

a receiving module 401, configured to receive CSI sent by a terminal;

a processing module 402, configured to determine that part of information in the CSI sent by the terminal is discarded, and decode the CSI according to a CSI discard rule adopted by the terminal; wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity.

The functions of the modules in the base station can be referred to the description of the functions implemented by the base station in the foregoing embodiments, and are not repeated here.

Based on the same technical concept, the embodiment of the present application further provides a communication device, which can implement the functions of the terminal side in the foregoing embodiments.

Referring to fig. 6, a schematic structural diagram of a communication device according to an embodiment of the present application is provided. As shown, the communication device may include: a processor 601, a memory 602, a transceiver 603, and a bus interface 604.

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 for receiving and transmitting data under the control of the processor 601.

The bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by processor 601, and various circuits of memory, represented by memory 602, being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any 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 process disclosed by the embodiment of the invention can be applied to the processor 601 or implemented by the processor 601. In implementation, the steps of the signal processing flow may be implemented by integrated logic circuits of hardware or instructions in the form of software in the processor 601. 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, discrete gate or transistor logic, discrete hardware components, or the like that implement or perform the methods, steps, and logic blocks disclosed in embodiments of the present invention. A 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 directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is 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 thereof.

Specifically, the processor 601 is configured to read the computer instructions in the memory 602 and execute the functions implemented on the terminal side in the flow shown in fig. 1 or fig. 2.

Based on the same technical concept, the embodiment of the present application further provides a communication device, which can implement the functions of the base station side in the foregoing embodiments.

Fig. 7 is a schematic structural diagram of a communication device according to an embodiment of the present application. As shown, the communication device may include: a processor 701, a memory 702, a transceiver 703, and a bus interface 704.

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 for receiving and transmitting data under the control of the processor 701.

The bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by processor 701, and various circuits, represented by memory 702, being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any 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 process 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 implemented by integrated logic circuits of hardware or instructions in the form of software in the processor 701. 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, discrete gate or transistor logic, discrete hardware components, or the like that may implement or perform the methods, steps, and logic blocks disclosed in embodiments of the present invention. A 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 directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is 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 the hardware thereof.

Specifically, the processor 701 is configured to read the computer instructions in the memory 702 and execute the functions implemented by the base station side in the flow shown in fig. 3.

The embodiment of the present application further provides a computer-readable storage medium, where the computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable the computer to execute the method executed by the terminal in the foregoing embodiment.

An embodiment of the present application further provides a computer-readable storage medium, where the computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are configured to enable the computer to execute the method performed by the base station in the foregoing embodiment.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams 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 invention 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. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A method for feeding back channel state information, comprising:

the terminal carries out channel measurement to obtain Channel State Information (CSI), wherein the CSI comprises at least one layer of nonzero coefficient set and nonzero coefficient position indication information;

the terminal discards part of information in the CSI according to a CSI discarding rule and uplink resources allocated to the terminal; wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity;

the terminal sends the CSI with part of information discarded to a base station; the CSI with the discarded part of information comprises a first part of CSI or a first part of CSI and a second part of CSI, wherein the first part of CSI comprises a Rank Indication (RI) and total number indication information of non-zero coefficients of all layers, and the second part of CSI comprises all or part of non-zero coefficients of at least one layer and non-zero coefficient position indication information.

2. The method of claim 1, wherein the discarding part of the information in the CSI comprises:

discarding part or all of non-zero coefficients of at least one layer in the CSI; or

Discarding part or all of the nonzero coefficient position indication information of at least one layer in the CSI; or

Discarding part or all of the non-zero coefficients of at least one layer of the CSI and part or all of the non-zero coefficient position indication information of at least one layer of the CSI.

3. The method of claim 1, wherein the first granularity is a portion or all of non-zero coefficient position indication information for a layer; or

The first granularity is a portion of non-zero coefficient position indication information for each layer.

4. The method of claim 1, wherein the second granularity is a fraction of all non-zero coefficients in the CSI.

5. The method of claim 1, wherein the discarding part of the information in the CSI comprises:

6. The method of claim 1, further comprising:

and the terminal discards at least one of the frequency domain base indication, the strongest coefficient index and the reference amplitude coefficient of at least one layer in the CSI.

7. A method for feeding back channel state information, comprising:

a base station receives Channel State Information (CSI) sent by a terminal, wherein the CSI comprises a first part of the CSI or a first part of the CSI and a second part of the CSI, the first part of the CSI comprises a Rank Indication (RI) and total number indication information of nonzero coefficients of all layers, and the second part of the CSI comprises all or part of nonzero coefficients of at least one layer and nonzero coefficient position indication information;

the base station determines that part of information in the CSI sent by the terminal is discarded, then determines an information domain contained in a second part of the CSI according to the first part of the CSI and a CSI discarding rule adopted by the terminal, and decodes the second part of the CSI according to the information domain contained in the second part of the CSI; wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity.

8. The method of claim 7, wherein the decoding the second portion of the CSI comprises:

9. The method of claim 7, wherein the first granularity is a portion or all of non-zero coefficient position indication information for a layer; or

10. The method of claim 7, in which the second granularity is a fraction of all non-zero coefficients in the CSI.

11. A channel state feedback terminal, comprising:

the processing module is used for carrying out channel measurement to obtain Channel State Information (CSI), wherein the CSI comprises at least one layer of nonzero coefficient set and nonzero coefficient position indication information; and

according to a CSI discarding rule and uplink resources allocated to the terminal, discarding part of information in the CSI; wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity;

a sending module, configured to send the CSI with the discarded part of the information to a base station; the CSI with the discarded part of information comprises a first part of CSI or a first part of CSI and a second part of CSI, wherein the first part of CSI comprises a Rank Indication (RI) and total number indication information of non-zero coefficients of all layers, and the second part of CSI comprises all or part of non-zero coefficients of at least one layer and non-zero coefficient position indication information.

12. A channel condition feedback base station, comprising:

the terminal comprises a receiving module and a processing module, wherein the receiving module is used for receiving Channel State Information (CSI) sent by a terminal, the CSI comprises a first part of the CSI or comprises the first part of the CSI and a second part of the CSI, the first part of the CSI comprises Rank Indication (RI) and total number indication information of nonzero coefficients of all layers, and the second part of the CSI comprises all or part of nonzero coefficients of at least one layer and nonzero coefficient position indication information;

a processing module, configured to determine that part of information in CSI sent by the terminal is discarded, determine, according to the first part of the CSI and a CSI discard rule adopted by the terminal, an information field included in the second part of the CSI, and decode, according to the information field included in the second part of the CSI, the second part of the CSI; wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity.

13. A channel state feedback communication device, comprising: a processor, memory, transceiver; the processor is used for reading the computer instructions in the memory and executing:

performing channel measurement to obtain Channel State Information (CSI), wherein the CSI comprises at least one layer of nonzero coefficient set and nonzero coefficient position indication information;

according to a CSI discarding rule and uplink resources allocated to a terminal, discarding part of information in the CSI; wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity;

transmitting, by the transceiver, the CSI with a part of information discarded to a base station; the CSI with the discarded part of information comprises a first part of CSI or a first part of CSI and a second part of CSI, wherein the first part of CSI comprises a Rank Indication (RI) and total number indication information of non-zero coefficients of all layers, and the second part of CSI comprises all or part of non-zero coefficients of at least one layer and non-zero coefficient position indication information.

14. The apparatus of claim 13, wherein the discarding part of the information in the CSI comprises:

15. The apparatus of claim 13, wherein the first granularity is a portion or all of non-zero coefficient position indication information for a layer; or

16. The apparatus of claim 13, in which the second granularity is a fraction of all non-zero coefficients in the CSI.

17. The apparatus as recited in claim 13, wherein said processor is specifically configured to:

determining non-zero coefficient position indication information which needs to be discarded in the CSI according to the first granularity, and discarding the non-zero coefficient position indication information which needs to be discarded; wherein the non-zero coefficient position indication information needing to be discarded comprises part or all of the non-zero coefficient position indication information of at least one layer;

comparing the number of the nonzero coefficients corresponding to the nonzero coefficient position indication information needing to be discarded with the number of the nonzero coefficients of the second granularity;

18. The apparatus of claim 13, wherein the processor is further configured to:

discarding at least one of a frequency-domain basis indicator, a strongest coefficient index, and a reference amplitude coefficient of at least one layer of the CSI.

19. A channel state feedback communication device, comprising: a processor, memory, transceiver; the processor is used for reading the computer instructions in the memory and executing:

receiving, by the transceiver, Channel State Information (CSI) sent by a terminal, where the CSI includes a first part of the CSI or includes the first part of the CSI and a second part of the CSI, the first part of the CSI includes a Rank Indication (RI) and total number indication information of non-zero coefficients of all layers, and the second part of the CSI includes all or part of non-zero coefficients of at least one layer and non-zero coefficient position indication information;

determining that part of information in the CSI sent by the terminal is discarded, determining an information field contained in a second part of the CSI according to the first part of the CSI and a CSI discarding rule adopted by the terminal, and decoding the second part of the CSI according to the information field contained in the second part of the CSI; wherein the CSI discard rule is used for indicating that the non-zero coefficient position indication information is discarded in units of a first granularity and/or the non-zero coefficient is discarded in units of a second granularity.

20. The apparatus as recited in claim 19, wherein said processor is specifically configured to:

determining the number of corresponding non-zero coefficients according to non-zero coefficient position indication information of a first layer in a second part of the CSI, wherein the first layer is one of all layers contained in the CSI;

comparing the number of nonzero coefficients indicated by the nonzero coefficient position indication information of the first layer with the number of nonzero coefficients contained in a nonzero coefficient information domain of the first layer;

and if the former is smaller than the latter, ignoring the non-zero coefficient which is not corresponding to the non-zero coefficient position indication information of the first layer in the non-zero coefficient information domain of the first layer.

21. The apparatus of claim 19, wherein the first granularity is a portion or all of non-zero coefficient position indication information for a layer; or

22. The apparatus of claim 19, in which the second granularity is a fraction of all non-zero coefficients in the CSI.

23. A computer-readable storage medium having stored thereon computer-executable instructions for causing a computer to perform the method of any one of claims 1-6.

24. A computer-readable storage medium having stored thereon computer-executable instructions for causing a computer to perform the method of any one of claims 7-10.