CN110958043A

CN110958043A - Feedback method and device of channel state information, terminal and base station

Info

Publication number: CN110958043A
Application number: CN201811132990.9A
Authority: CN
Inventors: 李辉; 高秋彬
Original assignee: China Academy of Telecommunications Technology CATT
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2018-09-27
Filing date: 2018-09-27
Publication date: 2020-04-03
Anticipated expiration: 2038-09-27
Also published as: WO2020063287A1; CN110958043B

Abstract

The application discloses a feedback method and device of channel state information, a terminal and a base station, wherein the feedback method of the channel state information comprises the following steps: the terminal determines PMI grouping in PMI information of N sub-bands; n is the number of sub-bands configured for the terminal by the base station to carry out Channel State Information (CSI) reporting; and aiming at one PMI group, the terminal selects M sub-bands from the N sub-bands according to the functional relation between the PMI information in the PMI group and feeds back the PMI information of the M sub-bands and sub-band indication information to the base station, wherein M is more than 0 and less than or equal to N, and the sub-band indication information is used for indicating the M sub-bands.

Description

Feedback method and device of channel state information, terminal and base station

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, a terminal, and a base station.

Background

In an NR (New RAT radio access technology) system, since a large number of antenna ports need to be supported and performance of MU-MIMO (Multi-User Multiple-Input Multiple-Output) needs to be improved, a more complex codebook needs to be designed. Specifically, there are three types of codebooks: a type I single panel codebook, a type I multi-panel codebook, and a type II single panel codebook. The codebook of the type I has lower quantization precision on a channel, and PMI feedback overhead is lower (the order of tens of bits); while the codebook of type II is designed for MU-MIMO, the quantization precision for the channel is high, and the PMI feedback overhead is large (on the order of several hundred bits).

The codebook of type II is generated based on beam combining, which is generated by L beams after amplitude and phase weighting, and L may be configured to be 2, 3 or 4.

The terminal calculates Channel State Information (CSI) through downlink Channel measurement. The CSI includes Channel Quality Indication (CQI), Rank Indication (RI), and Precoding Matrix Indication (PMI), and may further include Channel State Information reference signal (also referred to as sounding reference signal) (CSI-RS) resource Indication (CRI) Information.

The feedback of the type II codebook includes a wideband part and a subband part, wherein the wideband part performs parameter calculation and feedback for the entire configured bandwidth, and the subband part performs parameter calculation and feedback for each subband. When the number of subbands is large, the feedback overhead of the type II codebook is mainly determined by the subband portion. When the uplink resource capacity allocated by the base station for reporting the CSI is small, the current NR system allows half of the subband PMI information (discard odd subband PMI information) or all of the subband PMI information to be discarded, thereby ensuring that the remaining CSI can be reported on the uplink resource allocated by the base station. However, the discarding method is based on the principle of uniform sampling, and cannot be adjusted according to the characteristics of the actual channel, and when the channel characteristics are worse, the discarded subband PMI cannot be recovered accurately, which will cause the performance degradation of the system.

Disclosure of Invention

The embodiment of the application provides a channel state information feedback method and device, network equipment and a terminal, and is used for solving the technical problem that a discarded subband PMI cannot be accurately recovered when the existing channel state is severe.

The embodiment of the application provides the following specific technical scheme:

the embodiment of the application provides a feedback method of channel state information, which comprises the following steps:

the terminal determines PMI grouping in PMI information of N sub-bands; n is the number of sub-bands configured for the terminal by the base station to carry out Channel State Information (CSI) reporting;

and aiming at one PMI group, the terminal selects M sub-bands from the N sub-bands according to the functional relation between the PMI information in the PMI group and feeds back the PMI information of the M sub-bands and sub-band indication information to the base station, wherein M is more than 0 and less than or equal to N, and the sub-band indication information is used for indicating the M sub-bands.

In the embodiment of the application, the number of the sub-bands for CSI reporting configured by the base station for the terminal is N, and the terminal determines PMI groups in PMI information of the N sub-bands. And aiming at one PMI group, the terminal selects M subbands from N subbands according to the functional relation between PMI information in the PMI group for reporting, wherein M is more than 0 and less than or equal to N. And the terminal feeds back PMI information and subband indication information of the M subbands of each PMI group to the base station, wherein the subband indication information is used for indicating the M subbands. Therefore, the base station can determine the PMI information of the rest N-M sub-bands according to the received PMI information of the M sub-bands by using the functional relationship among the PMI information, so that the PMI information of the discarded sub-band is ensured to be accurately recovered, and the system performance is ensured. Meanwhile, the number M of the reported sub-bands can be adjusted by the terminal according to the capacity of the uplink resource, and the flexibility is high.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application.

FIG. 1 provides a system architecture diagram for an embodiment of the present application;

fig. 2 is a schematic flowchart of a feedback method of channel state information according to an embodiment of the present disclosure;

fig. 3 is a schematic diagram of a feedback method of channel state information according to an embodiment of the present application;

fig. 4 is a schematic diagram of a feedback method of channel state information according to an embodiment of the present application;

fig. 5 is a schematic diagram of a feedback method of channel state information according to an embodiment of the present application;

FIG. 6 is a schematic diagram of an apparatus according to an embodiment of the present disclosure;

FIG. 7 is a schematic structural diagram of another apparatus provided in an embodiment of the present application;

fig. 8 is a schematic structural diagram of a circuit system according to an embodiment of the present disclosure;

fig. 9 is a schematic structural diagram of another circuit system according to an embodiment of the present disclosure.

Detailed Description

The embodiment of the application provides a channel state information feedback method and device, network equipment and a terminal, and is used for solving the technical problems that the existing channel state information feedback method is high in cost and even influences the system performance.

The system operation environment of the present application is described below, and the technology described in the present application may be applied to an LTE system, such as an LTE/LTE-a/LTE system, or other wireless communication systems using various wireless access technologies, such as a system using Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Orthogonal Frequency Division Multiple Access (OFDMA), single carrier frequency division multiple access (SC-FDMA), etc., and a subsequent evolution system, such as a fifth generation 5G (new radio, NR), etc., and may also be extended to similar wireless communication systems, such as a wifi, wimax, and 3-related cellular systems.

Fig. 1 presents a schematic view of a communication system. The communication system may include at least one base station 100 (only 1 shown) and one or more terminals 200 connected to the base station 100.

The base station 100 may be a device that can communicate with the terminal 200. The base station 100 may be any device having a wireless transceiving function. Including but not limited to: a base station NodeB, an evolved node b, a base station in the fifth generation (5G) communication system, a base station or a base station in a future communication system, an access node in a WiFi system, a wireless relay node, a wireless backhaul node, and the like. The base station 100 may also be a radio controller in a Cloud Radio Access Network (CRAN) scenario. The base station 100 may also be a base station in a 5G network or a base station in a future evolution network; but also wearable devices or vehicle-mounted devices, etc. The base station 100 may also be a small station, a Transmission Reference Point (TRP), or the like. Although this application is not so limited.

The terminal 200 is a device with wireless transceiving function, which can be deployed on land, including indoors or outdoors, hand-held, worn or vehicle-mounted; can also be deployed on the water surface (such as a ship and the like); and may also be deployed in the air (e.g., airplanes, balloons, satellites, etc.). The terminal may be a mobile phone (mobile phone), a tablet computer (Pad), a computer with a wireless transceiving function, a Virtual Reality (VR) terminal, an Augmented Reality (AR) terminal, a wireless terminal in industrial control (industrial control), a wireless terminal in self driving (self driving), a wireless terminal in remote medical (remote medical), a wireless terminal in smart grid (smart grid), a wireless terminal in transportation safety (transportation safety), a wireless terminal in smart city (smart city), a wireless terminal in smart home (smart home), and the like. The embodiments of the present application do not limit the application scenarios. A terminal may also be referred to as a User Equipment (UE), an access terminal, a UE unit, a UE station, a mobile station, a remote terminal, a mobile device, a UE terminal, a wireless communication device, a UE agent, a UE device, or the like.

Multiple-input multiple-output (MIMO) technology uses multiple antennas to transmit multiple data in parallel, thereby obtaining additional spatial multiplexing gain. In order to better utilize the complex channel space characteristics, the transmitted data stream is usually precoded, and the signal is preprocessed by using the channel state information at the transmitting end to improve the signal transmission quality.

In the NR system, a type TypeII codebook is defined, and beamforming is implemented based on a way of linearly combining beams in a combined beam set. The beams in the combined set of beams are selected from a set of candidate beams. The TypeII codebook may support codebooks of rank 1 and rank 2. Where Rank is 1, the precoding matrix W may be represented as:

when Rank is 2, the precoding matrix W may be represented as:

wherein the coefficients in the precoding matrix can be expressed as

L represents the number of beams within the combined beam set,

indicating a beam with index (k1, k2) of the beam in the candidate beam set. Each beam in the candidate beam set may be represented by a 2-dimensional DFT vector obtained by Kronecker product of a DFT vector of a first dimension and a DFT vector of a second dimension, a beam index k1 representing an index of the DFT vector of the first dimension, and a beam index k2 representing an index of the DFT vector of the second dimension. The candidate beam set is determined according to the port configuration and the over-sampling rate of the base station side. Specifically, the number of antenna ports per polarization direction of the first dimension is defined to be N1, and K1 DFT vectors of the first dimension are generated by using O1-times oversampled DFT vectors, that is, K1 ═ N1 × O1, and two beam vectors at intervals of O1 beam vectors in the K1 first dimension are orthogonal to each other. Defining the number of antenna ports of each polarization direction of the second dimension as N2, generating K2 second dimension beam vectors, namely K2-N2 XO 2, by adopting O2 times of oversampled DFT vectors, wherein in the K2 second dimension beam vectors, every two beam vectors with the interval of O2 beam vectors are adoptedThe beam vectors are mutually orthogonal. Thus, the total number of beams in the candidate beam set is K1 × K2. For a dual-polarized antenna array, this beam vector is used for the antenna ports in one polarization direction.

The first polarization direction r is 0 and the second polarization direction r is 1, l is 0,1 denotes a layer, each layer corresponding to each column of the precoding matrix.

Representing a broadband amplitude factor acting on a beam i in the combined beam set in a polarization direction r and a layer I;

representing the subband amplitude factor acting on a beam i in the combined beam set in the polarization direction r and the l layer; c. C_r,l,iWhich represents the subband phase factor acting on beam i in the combined beam set in the polarization direction r and layer l. The codebook structure of the type II codebook may support a number of antenna ports of {4,8,12,16,24,32 }.

And for each layer, independently carrying out linear weighting on all beams in the combined beam set, and quantizing the amplitude and the phase in the linear weighting coefficient respectively to obtain a precoding matrix.

The feedback information of the terminal for the Type II codebook may include a wideband part and a subband part, where the wideband part performs weighting coefficient parameter calculation for the configured whole bandwidth and feeds back a wideband amplitude factor, and specifically, for the Type II codebook, if the base station is configured as wideband amplitude feedback (the weighting coefficient parameter is configured as 'false'), the wideband part needs to feed back the wideband amplitude factor of each beam on the whole bandwidth; and the sub-band part is used for calculating a weighting coefficient parameter for each sub-band and feeding back a sub-band amplitude factor and a sub-band phase factor of each beam on each sub-band. Specifically, if the base station is configured as subband amplitude feedback (the weighting coefficient parameter subband amplitude is configured as 'true'), for each subband, the terminal needs to feed back a subband amplitude factor and a subband phase factor of each beam. When the number of subbands is large, the feedback overhead of the Type II codebook is large. Therefore, the feedback overhead of the Type II codebook is mainly determined by the overhead of the subband portion needing feedback.

When the uplink resource capacity allocated by the base station for reporting the CSI is small, the current NR system allows half of the subband PMI information (discard odd subband PMI information) or all of the subband PMI information to be discarded, thereby ensuring that the remaining CSI can be reported on the uplink resource allocated by the base station. However, the discarding method is based on the principle of uniform sampling, and cannot be adjusted according to the characteristics of the actual channel, and when the channel characteristics are worse, the discarded subband PMI cannot be accurately recovered, which may cause system performance degradation. In addition, the current discarding mode adopts a fixed discarding granularity (or discards half of the subband PMIs, or discards all the subband PMIs), cannot be adjusted according to the capacity of the uplink resource, and is poor in flexibility.

In view of the above problem, as shown in fig. 2, the present application provides a method for feeding back channel state information, including:

step 201: the terminal determines PMI grouping in PMI information of N sub-bands; and N is the number of sub-bands which are configured for the terminal by the base station and used for CSI reporting.

Step 202: and aiming at one PMI group, the terminal selects M sub-bands from the N sub-bands according to the functional relation between the PMI information in the PMI group, wherein M is more than 0 and less than or equal to N.

Step 203: and the terminal feeds back the PMI information of the M sub-bands and sub-band indication information to the base station, wherein the sub-band indication information is used for indicating the M sub-bands.

Step 204: the base station receives PMI information and subband indication information of M subbands of the PMI group fed back by the terminal, wherein the subband indication information is used for indicating the M subbands.

Step 20: 5: and the base station determines PMI information of the rest N-M sub-bands according to the PMI information of the M sub-bands and the functional relation.

In step 201, the terminal determines a PMI packet in PMI information of N subbands, including:

the terminal determines a subband amplitude coefficient of the same layer and/or a subband phase coefficient of the same layer as a PMI group, or

The terminal determines all subband amplitude coefficients of the same layer and/or all subband phase coefficients of the same layer as a PMI group, or

And the terminal determines all the subband amplitude coefficients of all the layers and/or all the subband phase coefficients of all the layers to be one PMI group.

Specifically, for the number L of different synthesized beams, the system has agreed the number K of subband amplitude coefficients, and the number of subband phase coefficients is 2L, when RI is 1, that is, the number of layers is 1, the PMI information of a subband may be expressed as follows:

the subband amplitude coefficients are:

the subband phase coefficients are:

wherein p is_K,1(N) Kth sub-band of Nth sub-bandWith amplitude coefficient, c_2L,1And (N) is a 2L subband phase coefficient of the nth subband, wherein 1 represents RI ═ 1.

Then, for one subband amplitude coefficient in the same layer, it is a PMI group, and matrix 1 may be divided into K-1 PMI groups, which are: [ p ]_2,1(1) p_2,1(2) p_2,1(3) … p_2,1(N)]，[p_3,1(1) p_3,1(2) p_3,1(3) … p_3,1(N)]，……，[p_K,1(1) p_K,1(2) p_K,1(3) … p_K,1(N)]. That is, for matrix 1, each row is grouped as one PMI. Similarly, one subband phase coefficient for the same layer is one PMI group, that is, for matrix 2, it can be divided into 2L-1 PMI groups, and each row in matrix 2 is taken as one PMI group.

In addition, the same subband amplitude coefficient and subband phase coefficient of the same layer may be grouped as one PMI. Since the subband amplitude coefficients are K-1 and the subband phase coefficients are 2L-1, the first subband amplitude coefficient and the first subband phase coefficient are grouped into a PMI, the second subband amplitude coefficient and the second subband phase coefficient are grouped into a PMI, … … and so on. Expressed in matrix, the PMI groups are respectively:

……

wherein if K is 2L, the last PMI packet is

If K is not equal to 2L, the preceding PMI packet may be made to include subband amplitude coefficients and subband phase coefficients, and the following PMI packet may be made to include only subband amplitude coefficients or only subband phase coefficients.

All subband amplitude coefficients of the same layer or all subband phase coefficients of the same layer are grouped into one PMI, and since the RI is 1, only one layer is provided, all subband amplitude coefficients of the layer are grouped into one PMI, that is, the matrix 1 is used as one PMI group. Similarly, all subband phase coefficients of this layer are grouped into another PMI, i.e. matrix 2 is grouped into one PMI.

All subband amplitude coefficients and all subband phase coefficients of the same layer are in one PMI group, and since the RI is 1, only one layer is provided, all subband amplitude coefficients and all subband phase coefficients of the layer are in one PMI group, and the matrix 1 and the matrix 2 are in the same PMI group, that is, all subband PMI information is in one PMI group at this time.

When RI is 2, that is, the number of layers is 2, the PMI information of the subband may be expressed as follows:

subband amplitude coefficient of the first layer:

subband amplitude coefficient of the second layer:

subband phase coefficient of the first layer:

subband phase coefficient of the second layer:

wherein p is_K,1(N) is the Kth sub-band amplitude coefficient, p, of the Nth sub-band of the first layer_K,2(N) is the Kth sub-band amplitude coefficient of the Nth sub-band of the second layer, c_2L,1(N) is the 2L subband phase coefficient of the Nth subband in the first layer, c_2L,2(N) is the 2L sub-band of the Nth sub-band of the second layerWith phase coefficients.

For one subband amplitude coefficient of the same layer as one PMI group, the matrix 3 can be divided into K-1 PMI groups, which are respectively: [ p ]_2,1(1) p_2,1(2) p_2,1(3) … p_2,1(N)]，[p_3,1(1) p_3,1(2) p_3,1(3) … p_3,1(N)]，……，[p_K,1(1) p_K,1(2) p_K,1(3) … p_K,1(N)]. The matrix 5 may be divided into K-1 PMI groups, each: [ p ]_2,2(1) p_2,2(2) p_2,2(3) … p_2,2(N)]，[p_3,2(1) p_3,2(2) p_3,2(3) … p_3,2(N)]，……，[p_K,2(1) p_K,2(2) p_K,2(3) … p_K,2(N)]. That is, for matrix 3, each row is grouped as one PMI; for matrix 5, each row is grouped as one PMI.

Similarly, one subband phase coefficient for the same layer is a PMI group, that is, for the matrix 4, the PMI group can be divided into 2L-1 PMI groups, and each line in the matrix 4 is used as one PMI group; for matrix 6, it can be divided into 2L-1 PMI groups, with each row in matrix 6 being a PMI group.

In addition, the same subband amplitude coefficient of the same layer and the same subband phase coefficient of the same layer may be grouped as one PMI. Specifically, the first subband amplitude coefficient of the first layer and the first subband phase coefficient of the first layer are grouped as a PMI, the second subband amplitude coefficient of the first layer and the second subband phase coefficient of the first layer are grouped as a PMI, … … and so on. Grouping the first subband amplitude coefficient of the second layer and the first subband phase coefficient of the second layer as a PMI, grouping the second subband amplitude coefficient of the second layer and the second subband phase coefficient of the second layer as a PMI, … …, and so on.

One PMI group is set for all subband amplitude coefficients of the same layer or all subband phase coefficients of the same layer, and when RI is 2, one PMI group includes all subband amplitude coefficients or subband phase coefficients of the first layer, and one PMI group includes all subband amplitude coefficients or subband phase coefficients of the second layer, that is, matrix 3, matrix 4, matrix 5, and matrix 6 are each one PMI group.

For all subband amplitude coefficients of the same layer and all subband phase coefficients of the same layer are in one PMI group, all subband amplitude coefficients of the first layer and all subband phase coefficients of the first layer are in one PMI group, all subband amplitude coefficients of the second layer and all subband phase coefficients of the second layer are in one PMI group, that is, a matrix 3 and a matrix 5 are in one PMI group, and a matrix 4 and a matrix 6 are in one PMI group.

All subband amplitude coefficients of all layers or all subband phase coefficients of all layers are grouped into one PMI, namely all subband amplitude coefficients of all layers are grouped into one PMI, namely a matrix 3 and a matrix 4 are grouped into the same PMI; all subband phase coefficients of all layers are in one PMI group, that is, the matrix 5 and the matrix 6 are in the same PMI group.

All subband amplitude coefficients of all layers and all subband phase coefficients of all layers are grouped into one PMI, namely the matrix 3, the matrix 4, the matrix 5 and the matrix 6 are grouped into the same PMI, namely all subband PMI information is grouped into one PMI.

In step 202, the terminal selects M subbands from the N subbands according to the functional relationship between PMI information in the PMI packet. The M subbands may be uniformly distributed or non-uniformly distributed among the N subbands. According to the frequency selectivity of the channel, the same subband amplitude coefficient and/or subband phase coefficient may approximate some function, such as approximately linear distribution, or approximately piecewise linear distribution, that is, in the PMI group, the subband amplitude coefficient and/or the subband phase coefficient have a functional relationship among a plurality of subbands. Therefore, according to the functional relationship, M sub-bands can be selected from the N sub-bands needing to be reported, PMI information of the M sub-bands is reported, and PMI information of the rest N-M sub-bands is discarded, so that PMI information feedback is saved. Meanwhile, because M sub-bands are selected from N sub-bands according to the functional relationship, the base station can deduce PMI information of other N-M sub-bands according to the received PMI information of the M sub-bands and the corresponding functional relationship, thereby ensuring that the PMI information of the discarded sub-bands is accurately recovered and ensuring the system performance.

Further, the terminal receives a value of M configured for the terminal by the base station;

or the terminal determines the value of M and feeds back or does not feed back to the base station.

In a specific implementation process, the value of M may be determined by the terminal according to the uplink resource, may be configured by the base station for the terminal, or may be predefined by the system, which is not limited herein. In the embodiment of the invention, the number M of the reported sub-bands can be adjusted according to the capacity of the uplink resource, and the flexibility is higher.

In the embodiment of the present invention, the functional relationship between the PMI information is sent to the terminal by the base station, or predefined by the system, that is, predefined between the terminal and the base station, or determined by the terminal, which is not limited herein.

Further, the subband indication information in the embodiment of the present invention may be:

the indices of the M subbands or the indices of the remaining N-M subbands, or

Bit pattern indication of the M subbands in the N subbands or bit pattern indication of the remaining N-M subbands in the N subbands, or

Sampling factors and offset values of the M subbands in the N subbands or sampling factors and offset values of the remaining N-M subbands in the N subbands.

In a specific implementation process, the sub-band indication information can indicate M sub-bands, the base station directly determines the M sub-bands reported by the terminal according to the sub-band indication information, and deduces the indication information of the rest N-M sub-bands from the sub-band indication information; or the sub-band indication information may indicate the remaining N-M sub-bands, the base station may directly determine the N-M sub-bands discarded by the terminal according to the sub-band indication information, and derive the indication information of the M sub-bands reported by the terminal from the sub-band indication information.

In addition, in the embodiment of the present invention, the subband indicating information may be in the form of an index of a subband, such as N in matrix 1 to matrix 6. Or the form of the sub-band indication information can be a bit pattern indication of the sub-band, for example, N bits are used, wherein M bits take a value of 1 to indicate M reported sub-bands, and the remaining N-M bits take a value of 0 to indicate discarded N-M sub-bands. The subband coefficients circled by the rectangular frame shown in fig. 3 are PMI information of M subbands reported in one PMI packet, and may be expressed as 01001 …. (N bits in total). Or the form of the sub-band indication information can be a sampling factor and an offset value, and the terminal or the base station can determine the position of the reported sub-band coefficient and the value of the M according to the sampling factor and the offset value. For example, in fig. 3, the base station configures N-16 subbands for terminal feedback, and the terminal determines that the sampling factor is 3 according to the uplink resource allocated by the base station and the code rate requirement agreed by the system, that is, one subband is selected from each 3 subbands in the N-16 subbands to report PMI information. The terminal determines that the offset value is 1, and the offset value can be obtained by determining an appropriate sampling point from the distribution of the subband amplitude coefficient and the subband phase coefficient. Then the M subbands are selected to be subbands N ═ {2,5,8,11,14}, where M takes the value 5.

In order to more clearly understand the present invention, the above-mentioned process is described in detail below with specific examples.

Example one

The base station is assumed to configure the terminal to feed back the Type II CSI information of the sub-bands with N being 16, and allocate uplink resources for the terminal to perform CSI feedback. The base station configures the number L of synthesized beams in the Type II codebook to be 4 (at this time, the number K of subband amplitude coefficients agreed by the system to be 6).

The terminal receives codebook configuration information of the base station and determines PMI information of the N-16 sub-bands. Assuming that the terminal determines RI to be 2, subband amplitude coefficients and subband phase coefficients included in PMI information of N to 16 subbands in the corresponding CSI information are as follows:

subband amplitude coefficient of the first layer:

subband amplitude coefficient of the second layer:

subband phase coefficient of the first layer:

subband phase coefficient of the second layer:

if the system is appointed, one PMI group comprises all subband amplitude coefficients of all layers and all subband phase coefficients of all layers; the M sub-bands are appointed to adopt a uniform distribution mode, and the indication information of the sub-bands is a sampling factor and an offset value. And the terminal determines the sampling factor to be 3 according to the uplink resource allocated by the base station and the code rate requirement agreed by the system, namely, PMI information is reported from every 3 sub-bands in the N-16 sub-bands. The offset values may be derived from determining appropriate sample points based on the distribution of subband magnitude coefficients and subband phase coefficients (e.g., based on piecewise linear characteristics of the subband coefficients). For example, when the terminal determines that the offset value is 1, it selects PMI information of a subband having N ═ {2,5,8,11,14}, such as a subband coefficient in the block of fig. 3, and reports the PMI information. In this case, M takes a value of 5. While PMI information for the remaining subbands is discarded.

And the base station receives the PMI information of the M-5 sub-bands and simultaneously receives the sampling factor and the offset value reported by the terminal. The base station determines the subband amplitude coefficients and the subband phase coefficients of the 11 discarded subbands by adopting a linear interpolation method.

Example two

subband amplitude coefficient of the first layer:

subband amplitude coefficient of the second layer:

subband phase coefficient of the first layer:

subband phase coefficient of the second layer:

if all the subband amplitude coefficients of the same layer and all the subband phase coefficients of the same layer are determined to be one PMI group, all the subband coefficients are divided into two groups. The system appoints M sub-bands to adopt a non-uniform distribution mode, and the indication information of the sub-bands is the index values of the M sub-bands of each layer. And the terminal determines that M is 4 according to the uplink resources allocated by the base station and the code rate requirement agreed by the system. And the subband index values may be derived by determining appropriate sample points based on the distribution of subband magnitude coefficients and subband phase coefficients (e.g., based on piecewise linear behavior of the subband coefficients). For example, the terminal determines that M subbands in the first layer are N ═ {1,2,5,16}, and M subbands in the second layer are N ═ {1,3,4,16}, as shown by the subband coefficients in the box of fig. 4. And discarding the PMI information of the sub-bands in the CSI information of the other sub-bands. And the terminal reports the indexes of the M sub-bands of each layer to the base station.

For each PMI packet (i.e., each layer), the base station receives the PMI information of the M-4 subbands, and receives an index of the M-4 subbands reported by the terminal for each layer. The base station determines the subband amplitude coefficients and the subband phase coefficients of 12 discarded subbands in each layer by adopting a linear interpolation method.

EXAMPLE III

And the terminal receives codebook configuration information of the base station and determines the Type II CSI of the sub-bands with the N being 16. Assuming that the terminal determines that RI is 1, that is, the number of layers is 1, subband amplitude coefficients and subband phase coefficients included in N-16 subband PMIs in the corresponding CSI information are as follows:

subband amplitude coefficient:

subband phase coefficient:

if a sub-band amplitude coefficient of the same layer or a sub-band phase coefficient of the same layer is determined to be a PMI group, all sub-band coefficients are divided into K-1+2L-1 groups. Assume that the system agrees that M subbands adopt a non-uniform distribution mode, and the subband indication information is the index values of the M subbands. And the terminal determines that M is 4 according to the uplink resources allocated by the base station and the code rate requirement agreed by the system. The index value for each subband coefficient may be derived by determining the appropriate sample point based on the distribution of the subband coefficients (e.g., based on the piecewise linear characteristic of the subband coefficients). E.g. terminal determining PMI packet p_2,1(1) p_2,1(2) p_2,1(3) …p_2,1(N)]Is N ═ {1,2,5,16}, PMI group [ p ═ is grouped_K,1(1) p_K,1(2) p_K,1(3) … p_K,1(N)]Is {1,3,4,5}, etc. Such as the subband coefficients in the box of fig. 5. I.e. subband selection is done independently for each subband coefficient of each layer. And sub-bands PM of the remaining sub-bandsThe I information is discarded. And the terminal reports the M subband indexes of each PMI group to the base station.

And the base station receives the sub-band PMI information of the M sub-bands, and simultaneously receives the index of 4 sub-bands of each sub-band PMI information reported by the terminal. The base station determines the sub-band PMI information of 12 discarded sub-bands by adopting a linear interpolation method.

Based on the same application concept, as shown in fig. 6, an apparatus 20 provided in the embodiment of the present application includes at least one processor 21, a communication bus 22, a memory 23, and at least one communication interface 24.

Illustratively, the terminal 200 in fig. 1 may also be the apparatus 20 shown in fig. 6. The apparatus 20 may implement the steps related to the terminal in the feedback method of the channel state information in the embodiment of the present application through the processor 21.

For example, the base station 100 in fig. 1 may also be the apparatus 20 shown in fig. 6, and the apparatus 20 may implement, through the processor 21, the steps related to the network device in the feedback method of channel state information in the embodiment of the present application.

The processor 21 may be a general purpose Central Processing Unit (CPU), microprocessor, application-specific integrated circuit (ASIC), or one or more ics for controlling the execution of programs in accordance with the teachings of the present application.

Communication bus 22 may include a path that transfers information between the aforementioned components. The communication interface 24 may be any device, such as a transceiver, for communicating with other devices or communication networks, such as an ethernet network, a Radio Access Network (RAN), a wlan, etc.

The memory 23 may be a read-only memory (ROM) or other type of static storage device that can store static information and instructions, a Random Access Memory (RAM) or other type of dynamic storage device that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compact disc, laser disc, optical disc, digital versatile disc, blu-ray disc, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by the apparatus, but is not limited to these. The memory may be self-contained and coupled to the processor via a bus. The memory may also be integral to the processor.

The memory 23 is used for storing application program codes for executing the scheme of the application, and is controlled by the processor 21 to execute. The processor 21 is configured to execute application program code stored in the memory 23.

In particular implementations, processor 21 may include one or more CPUs such as CPU0 and CPU1 in fig. 6, for example, as an example.

In particular implementations, the apparatus 20 may include a plurality of processors, such as the processor 21 and the processor 28 in fig. 7, as an example. Each of these processors may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. A processor herein may refer to one or more devices, circuits, and/or processing cores for processing data (e.g., computer program instructions).

In the embodiment of the present application, the functional modules of the apparatus shown in fig. 6 may be divided according to the above method example, for example, each functional module may be divided according to each function, or two or more functions may be integrated into one processing module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. It should be noted that, in the embodiment of the present application, the division of the module is schematic, and is only one logic function division, and there may be another division manner in actual implementation.

In the present embodiment, the apparatus shown in fig. 6 is presented in a form of dividing each functional module corresponding to each function, or the apparatus is presented in a form of dividing each functional module in an integrated manner. A "module" as used herein may refer to an application-specific integrated circuit (ASIC), an electronic circuit, a processor and memory that execute one or more software or firmware programs, an integrated logic circuit, and/or other devices that provide the described functionality.

For example, in the case of dividing each functional module by corresponding functions, fig. 7 shows a possible structural schematic diagram of the apparatus in the foregoing embodiment, and the apparatus 900 may be a terminal or a network device in the foregoing embodiment. The apparatus 900 comprises a processing unit 901 and a transceiving unit 902. The transceiver unit 902 is used for the processing unit 901 to transmit and receive signals. The method executed by the processing unit 901 in fig. 7 may be implemented by the processor 21 (and/or the processor 28) and the memory 23 in fig. 6, and specifically, the method executed by the processing unit 901 may be executed by the processor 21 (and/or the processor 28) in fig. 6 to call the application program code stored in the memory 23, which is not limited in this embodiment of the present application.

In a specific implementation, taking the apparatus 900 may be a terminal in the foregoing embodiment as an example, an embodiment of the present application provides a feedback apparatus of channel state information, including:

a processing unit 901, configured to determine PMI packets in PMI information of N subbands; n is the number of sub-bands configured for the terminal by the base station to carry out Channel State Information (CSI) reporting; for one PMI group, selecting M sub-bands from the N sub-bands according to the functional relation between PMI information in the PMI group; wherein 0< M is less than or equal to N, and the subband indicating information is used for indicating the M subbands;

a transceiver unit 902, configured to feed the PMI information of the M subbands and the subband indication information back to the base station.

In a possible implementation manner, the processing unit 901 is specifically configured to determine that one subband amplitude coefficient of the same layer and/or one subband phase coefficient of the same layer is a PMI packet, or

Determining all subband amplitude coefficients of the same layer and/or all subband phase coefficients of the same layer as a PMI packet, or

And determining all subband amplitude coefficients of all layers and/or all subband phase coefficients of all layers as a PMI group.

In a possible implementation manner, the subband indication information is:

the indices of the M subbands or the indices of the remaining N-M subbands, or

In a possible implementation manner, the transceiver unit 902 is further configured to receive a value of the M configured by the base station;

or feeding back or not feeding back the value of the M to the base station.

In a possible implementation manner, the functional relationship is sent to the terminal by the base station, or predefined by a system, or determined by the terminal itself.

Based on the same application concept, an embodiment of the present application further provides a circuit system, and fig. 8 is a schematic structural diagram of the circuit system provided in the embodiment of the present application (for example, a communication device such as an access point, a base station, a station, or a terminal).

As shown in fig. 8, circuitry 1200 may be implemented by a bus 1201 as a general bus architecture. The bus 1201 may include any number of interconnecting buses and bridges depending on the specific application of the circuit system 1200 and the overall design constraints. The bus 1201 couples various circuits together including the processor 1202, the storage medium 1203, and the bus interface 1204. Optionally, circuitry 1200 connects a network adapter 1205 or the like via bus 1201 using bus interface 1204. The network adapter 1205 may be used to implement signal processing functions at the physical layer of the wireless communication network and to transmit and receive radio frequency signals through the antenna 1207. The user interface 1206 may connect user terminals, such as: a keyboard, a display, a mouse or a joystick, etc. The bus 1201 may also connect various other circuits such as timing sources, peripherals, voltage regulators, or power management circuits, which are well known in the art, and therefore, will not be described in detail.

Alternatively, circuitry 1200 may be configured as a chip or system on a chip that includes one or more microprocessors that provide processor functions; and an external memory providing at least a portion of the storage medium 1203, all connected together with other support circuitry through an external bus architecture.

Alternatively, the circuitry 1200 may be implemented using an ASIC (application specific integrated circuit) having a processor 1202, a bus interface 1204, and a user interface 1206; and at least a portion of storage medium 1203 integrated within a single chip, or circuitry 1200 may be implemented using one or more FPGAs (field programmable gate arrays), PLDs (programmable logic devices), controllers, state machines, gated logic, discrete hardware components, any other suitable circuitry, or any combination of circuitry capable of performing the various functions described throughout this application.

Among other things, the processor 1202 is responsible for managing the bus and general processing (including executing software stored on the storage medium 1203). The processor 1202 may be implemented using one or more general-purpose processors and/or special-purpose processors. Examples of processors include microprocessors, microcontrollers, DSP processors, and other circuits capable of executing software. Software should be construed broadly to mean instructions, data, or any combination thereof, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

In the following figures the storage medium 1203 is shown separate from the processor 1202, however, it will be readily apparent to those skilled in the art that the storage medium 1203, or any portion thereof, may be located outside of the circuitry 1200. The storage medium 1203 may include, for example, a transmission line, a carrier wave modulated with data, and/or a computer product separate from the wireless node, all of which may be accessed by the processor 1202 through the bus interface 1204. Alternatively, the storage medium 1203, or any portion thereof, may be integrated into the processor 1202, e.g., may be a cache and/or general purpose registers.

The processor 1202 may execute the signal status information feedback method in any of the embodiments described above in the present application, and details are not described herein again.

Fig. 9 is another structural diagram of a circuit system according to an embodiment of the present application. The circuitry may be a processor. The processor may be embodied as a chip or a System On Chip (SOC) and is disposed in a base station or a terminal of the wireless communication system according to the embodiment of the present application, so that the base station or the terminal implements the feedback method of the channel state information according to the embodiment of the present application. As shown in fig. 9, the circuit system 60 includes: an interface unit 601, a control and arithmetic unit 602, and a storage unit 603. Wherein the interface unit is adapted to communicate with other components of the base station or the terminal, the storage unit 603 is adapted to store computer programs or instructions, and the control and arithmetic unit 602 is adapted to decode and execute these computer programs or instructions. It will be appreciated that these computer programs or instructions may include the terminal functionality described above, as well as the base station functionality described above. When the terminal function program is decoded and executed by the control and operation unit 602, the terminal can implement the indication method of the uplink sub-band precoding matrix and the function of the terminal in the embodiment of the present application. When the base station function program is decoded and executed by the control and operation unit 602, the base station can implement the function of the base station in the signal status information feedback method according to the embodiment of the present application.

In one possible design, these terminal or base station functions are stored in memory external to circuitry 60. When the terminal function program or the base station function program is decoded and executed by the control and arithmetic unit 602, the storage unit 603 temporarily stores part or all of the contents of the terminal function program or part or all of the contents of the base station function program.

In an alternative implementation, these terminal or base station functions are provided in a memory unit 603 stored within the circuitry 60. When the terminal function program is stored in the storage unit 603 inside the circuit system 60, the circuit system 60 may be provided in the terminal 200 of the wireless communication system of the embodiment of the present application. When the base station function program is stored in the storage unit 603 inside the circuit system 60, the circuit system 60 may be provided in the base station 100 of the wireless communication system of the embodiment of the present application.

In yet another alternative implementation, the contents of some of these terminal or base station functions are stored in memory external to circuitry 60, and the contents of other parts of these terminal or base station functions are stored in memory unit 603 internal to circuitry 60.

Based on the same idea, the present application provides a computer-readable storage medium having stored therein instructions, which, when run on a computer, cause the computer to perform the method steps related to the terminal in the various embodiments to which the present application relates.

Based on the same concept, the present application provides a computer-readable storage medium having stored therein instructions, which, when run on a computer, cause the computer to perform the method steps related to the base station in the various embodiments to which the present application relates.

Based on the same idea, the present application provides a computer program product comprising instructions which, when run on a computer, cause the computer to perform the method steps related to the terminal in the various embodiments to which the present application relates.

Based on the same idea, the present application provides a computer program product comprising instructions which, when run on a computer, cause the computer to perform the method steps related to the base station in the various embodiments to which the present application relates.

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the application to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website site, computer, server, or data center to another website site, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., Solid State Disk (SSD)), among others.

It can be clearly understood by those skilled in the art that the descriptions of the embodiments provided in the present application may refer to each other, and for convenience and brevity of the description, the functions and the executed steps of the devices and the apparatuses provided in the embodiments of the present application may refer to the relevant descriptions of the method embodiments of the present application, which are not repeated herein.

While the present application has been described in connection with various embodiments, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed application, from a review of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, apparatus (device), or computer program product. Accordingly, this application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects that may all generally be referred to herein as a "module" or "system. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein. A computer program stored/distributed on a suitable medium supplied together with or as part of other hardware, may also take other distributed forms, such as via the Internet or other wired or wireless telecommunication systems.

Those skilled in the art will also appreciate that the various illustrative logical blocks and steps (step) set forth in the embodiments of the present application may be implemented in electronic hardware, computer software, or combinations of both. To clearly illustrate the interchangeability of hardware and software, various illustrative components and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design requirements of the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the embodiments of the present application.

The various illustrative logical blocks, modules, and circuits described in connection with the embodiments disclosed herein may be implemented or operated as a general purpose processing unit, a digital signal processing unit, an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processing unit may be a micro processing unit, which may alternatively be any conventional processing unit, controller, microcontroller, or state machine. A processing unit may also be implemented as a combination of computing devices, e.g., a digital signal processing unit and a micro-processing unit, a plurality of micro-processing units, one or more micro-processing units in conjunction with a digital signal processing unit core, or any other similar configuration.

In one or more exemplary designs, the functions described in the embodiments of the present application may be implemented in hardware, software, firmware, or any combination of the three. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media that facilitate transfer of a computer program from one place to another. Storage media may be any available media that can be accessed by a general purpose or special purpose computer. For example, such computer-readable media can include, but is not limited to, RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store program code in the form of instructions or data structures and which can be read by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processing unit. Additionally, any connection is properly termed a computer-readable medium, and, thus, is included if the software is transmitted from a website, server, or other remote source over a coaxial cable, fiber optic computer, twisted pair, Digital Subscriber Line (DSL), or wirelessly, e.g., infrared, radio, and microwave. Such discs (disk) and disks (disc) include compact disks, laser disks, optical disks, DVDs, floppy disks and blu-ray disks where disks usually reproduce data magnetically, while disks usually reproduce data optically with lasers. Combinations of the above may also be included in the computer-readable medium.

The foregoing description of the specification may enable any person skilled in the art to make or use the teachings of the present application, and any modifications based on the disclosed teachings should be considered as obvious in the art, and the general principles described herein may be applied to other variations without departing from the spirit or scope of the present application. Thus, the disclosure is not intended to be limited to the embodiments and designs described, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

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

2. The method of claim 1, wherein the terminal determines the PMI grouping in the PMI information for the N subbands, comprising:

3. The method of claim 1, wherein the subband indication information is:

the indices of the M subbands or the indices of the remaining N-M subbands, or

4. The method of any of claims 1 to 3, further comprising:

the terminal receives the value of the M configured for the terminal by the base station;

or the terminal determines the value of the M and feeds back or does not feed back the value to the base station.

5. A method according to any one of claims 1 to 3, wherein the functional relationship is sent by the base station to the terminal, or is predefined by the system, or is determined by the terminal itself.

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

a base station receives PMI information and subband indication information of M subbands of a PMI group fed back by a terminal, wherein the subband indication information is used for indicating the M subbands;

and the PMI information of the M subbands is PMI information of the M subbands selected by the terminal from N subbands according to a functional relation between PMI information in the PMI group, wherein N is the number of subbands which are configured by the base station for the terminal and used for CSI reporting, and M is more than 0 and less than or equal to N.

7. The method as claimed in claim 6, wherein after the base station receives the PMI information and the subband indication information of the M subbands fed back by the terminal, the method further comprises:

and the base station determines PMI information of the rest N-M sub-bands according to the PMI information of the M sub-bands and the functional relation.

8. The method of claim 6, wherein one subband amplitude coefficient of the same layer and/or one subband phase coefficient of the same layer is one PMI packet, or

All subband amplitude coefficients of the same layer and/or all subband phase coefficients of the same layer are grouped as a PMI, or

All subband amplitude coefficients of all layers and/or all subband phase coefficients of all layers are one PMI group.

9. The method of claim 6, wherein the subband indication information is:

the indices of the M subbands or the indices of the remaining N-M subbands, or

10. The method of any of claims 6 to 9, further comprising:

the base station configures the value of the M for the terminal and sends the value to the terminal;

or, the base station receives the value of the M determined by the terminal.

11. A method according to any one of claims 6 to 9, wherein the functional relationship is either signaled by the terminal to the base station, predefined by the system, or determined by the base station itself.

12. An apparatus for feeding back channel state information, comprising:

a processing unit, configured to determine a PMI group in PMI information of the N subbands; n is the number of sub-bands configured for the terminal by the base station to carry out Channel State Information (CSI) reporting; for one PMI group, selecting M sub-bands from the N sub-bands according to the functional relation between PMI information in the PMI group; wherein 0< M is less than or equal to N, and the subband indicating information is used for indicating the M subbands;

and the transceiver unit is used for feeding back the PMI information and the subband indication information of the M subbands to the base station.

13. An apparatus for feeding back channel state information, comprising:

a transceiver unit, configured to receive PMI information and subband indication information of M subbands of a PMI packet fed back by a terminal, where the subband indication information is used to indicate the M subbands; the PMI information of the M subbands is the PMI information of the M subbands selected by the terminal from N subbands according to the functional relation between the PMI information in the PMI group, wherein N is the number of the subbands which are configured by the base station for the terminal and used for CSI reporting, and M is more than 0 and less than or equal to N;

and the processing unit is used for determining the PMI information of the rest N-M sub-bands according to the PMI information of the M sub-bands and the functional relation.

14. A terminal, comprising: the system comprises a processor, a memory, a transceiver and a bus interface, wherein the processor, the memory and the transceiver are connected through the bus interface;

the processor is configured to determine PMI groups in PMI information of the N subbands; n is the number of sub-bands configured for the terminal by the base station to carry out Channel State Information (CSI) reporting; for one PMI group, selecting M sub-bands from the N sub-bands according to the functional relation between PMI information in the PMI group; wherein 0< M is less than or equal to N, and the subband indicating information is used for indicating the M subbands;

the transceiver is configured to feed back PMI information and subband indication information of the M subbands to the base station;

the memory is used for storing one or more executable programs and storing data used by the processor when executing operations;

and the bus interface is used for providing an interface.

15. A base station, comprising: the system comprises a processor, a memory, a transceiver and a bus interface, wherein the processor, the memory and the transceiver are connected through the bus interface;

the transceiver is configured to receive PMI information of M subbands of a PMI packet and subband indication information fed back by a terminal, where the subband indication information is used to indicate the M subbands; the PMI information of the M subbands is the PMI information of the M subbands selected by the terminal from N subbands according to the functional relation between the PMI information in the PMI group, wherein N is the number of the subbands which are configured by the base station for the terminal and used for CSI reporting, and M is more than 0 and less than or equal to N;

the processor is configured to determine PMI information of the remaining N-M subbands according to the PMI information of the M subbands and the functional relationship;

and the bus interface is used for providing an interface.