WO2019218906A1

WO2019218906A1 - Precoding matrix indication method and related apparatus

Info

Publication number: WO2019218906A1
Application number: PCT/CN2019/085947
Authority: WO
Inventors: 杭海存; 金黄平; 毕晓艳; 王峰; 尚鹏; 贾明
Original assignee: 华为技术有限公司
Priority date: 2018-05-15
Filing date: 2019-05-08
Publication date: 2019-11-21
Also published as: CN110492916B; CN110492916A

Abstract

Provided by the present application are a precoding matrix indication method and a related apparatus, comprising: a transmitting terminal determines a precoding matrix indicator (PMI) of at least one first subband group in a broadband and a PMI of at least one second subband group in the broadband, wherein the PMI of the first subband group is an absolute PMI determined on the basis of a reference codebook or a differential PMI determined on the basis of a differential codebook, the PMI of the second subband group is based on a differential PMI determined in the differential codebook, and the differential codebook is obtained by mapping from the reference codebook; and the transmitting terminal transmits the PMI of the at least one first subband group and the PMI of the at least one second subband group. Hence, the embodiments of the present application allow each subband group to have a corresponding absolute PMI or a differential PMI, and precoding matrices used in the subbands in a same subband group are the same, while the precoding matrices used in different subband groups may be different, thereby improving the anti-interference ability between the subband groups, and greatly improving the frequency spectrum efficiency and performance of a system.

Description

Precoding matrix indication method and related equipment

Technical field

The present application relates to the field of communications technologies, and in particular, to a precoding matrix indication method and related device.

Background technique

At present, Massive Multiple Input and Multiple Output (Massive MIMO) systems can achieve significant spectral efficiency improvements through large-scale antennas, and the accuracy of channel information obtained by base stations largely determines The performance of Massive MIMO, therefore, the codebook is usually used to quantize channel information. When performing codebook quantization channel information, it is necessary to approximate the original channel characteristics as much as possible under the allowable overhead, so that channel quantization is more accurate.

For example, in the currently designed codebook quantization, in the downlink system, a two-stage codebook design is adopted, that is, a method using a wideband codebook and a narrowband codebook, and the wideband codebook is used to select a precoding matrix for the wideband channel. The narrowband codebook is used to combine the precoding matrix selected by the wideband channel into a narrowband selective precoding matrix. In the uplink system, a primary codebook design is adopted, that is, in the scheduling frequency band of the terminal device, the base station selects a precoding matrix for the scheduling frequency band from the primary codebook for uplink transmission.

It can be seen that the channel quantization in the downlink system and the channel quantization in the uplink system all adopt a precoding matrix, which causes large interference between the sub-bands, thereby reducing the spectrum efficiency of the system.

Summary of the invention

The present application provides a precoding matrix indication method and related equipment, which can improve system spectrum efficiency and reduce signaling overhead.

In one aspect, the present application provides a precoding matrix indication method, where a transmitting end determines a precoding matrix indication of at least one first subband group in a wideband and a precoding of at least one second subband group in the broadband. a matrix indication; the precoding matrix indication of the first subband group is an absolute precoding matrix indication determined based on a reference codebook, or a differential precoding matrix indication determined based on a differential codebook; the second subband group The precoding matrix indication is a differential precoding matrix indication determined based on the differential codebook; the differential codebook is mapped from the reference codebook; and the transmitting end transmits the precoding corresponding to the at least one first subband group The matrix indicates a precoding matrix indication corresponding to the at least one second subband group.

Wherein the differential codebook is mapped from the reference codebook, that is, the codeword included in the differential codebook is selected from a codeword that satisfies a preset rule in the reference codebook, or is a reference codebook. The beam coefficients of the codewords are obtained by differential operation.

The absolute precoding matrix indication (ie, absolute PMI) is an index or label of the codeword in the reference codebook, and may also be referred to as a reference PMI, a basic PMI, etc.; the differential precoding matrix indication (ie, differential PMI) is a codeword at An index or label in a differential codebook may also be referred to as a relative PMI. Codewords can also be referred to as precoding matrices. Therefore, the differential codebook is mapped from the reference codebook, which means that each differential PMI in the differential codebook corresponds to a partial codeword in the reference codebook, or corresponds to a partial absolute PMI in the reference codebook.

Since the codeword in the differential codebook is obtained by selecting a partial codeword from the reference codebook, the number of codewords included in the differential codebook is smaller than the number of codewords included in the reference codebook, so the same codeword is in the differential codebook. The number of bits of the differential PMI is less than the number of bits of the absolute PMI of the codeword in the reference codebook. Therefore, in the embodiment of the present application, the precoding matrix indication information sent by the transmitting end includes the differential PMI, and the signaling overhead can be reduced compared with the manner that the absolute PMI is used to indicate the codeword. In addition, in this embodiment of the present application, each subband group has a corresponding absolute PMI or a differential PMI, and the precoding matrix used in the subbands in the same subband group is the same, and the precoding matrix used in each subband group may be different. Therefore, the anti-interference ability between each sub-band group can be improved, and the spectrum efficiency and system performance of the system are greatly improved.

In an optional implementation manner, the precoding matrix indication of the first subband group is an absolute PMI determined based on the reference codebook, and may include the following step: the transmitting end selects the first part from the reference codebook a codeword of a subband group; the transmitting end determines an absolute PMI of the first subband group based on a codeword of the first subband group. The transmitting end may select, according to the measured channel information of the first subband group, the codeword of the first subband group from the reference codebook; correspondingly, the transmitting end uses the absolute PMI of the codeword in the reference codebook as The PMI of the first subband group.

In an optional implementation manner, the precoding matrix indication corresponding to the first subband group is a differential PMI determined based on the differential codebook, and the differential codebook is a differential codebook corresponding to the wideband codeword.

In the uplink system, the broadband may be the full bandwidth channel of the uplink, or may only refer to the bandwidth scheduled by the terminal device; in the downlink system, the bandwidth may be the bandwidth obtained by the terminal device according to the measurement.

Specifically, the determining, by the transmitting end, the differential PMI of the first subband group may include the following steps: the transmitting end selects a codeword of the first subband group from the differential codebook; and the transmitting end determines the according to the codeword. a differential precoding matrix indication of the first subband group; the differential codebook is obtained by wideband codeword mapping, and the wideband codeword is used by the transmitting end according to the measured broadband channel information from the reference codebook Selected. Or determining, by the transmitting end, the differential PMI of the first subband group may include the following steps: the transmitting end determines a differential precoding matrix indication of the first subband group from the differential codebook, where the differential codebook is by the broadband Obtained by the codeword mapping, the wideband codeword is selected by the transmitting end from the reference codebook according to the measured broadband channel information.

In an optional implementation manner, the precoding matrix indication of the second subband group is a differential PMI determined based on a differential codebook, where the differential codebook is a subband adjacent to the second subband group. The codeword mapping of the group, that is, the differential codebook corresponding to the codeword of the adjacent subband group. It can be seen that since the channel has a certain channel correlation in the frequency domain, if the correlation between adjacent sub-bands is relatively high, the channel difference is correspondingly small, and therefore, from the second sub-band group When the codeword is selected in the differential codebook corresponding to the codeword of the adjacent subband group, on the one hand, the channel can be more accurately approximated. On the other hand, the codeword selected from the differential codebook can feed back the codeword when the PMI is fed back. The differential PMI can thus reduce signaling overhead.

In this implementation manner, the determining, by the transmitting end, the differential PMI of the second subband group may include the following steps: the transmitting end determines a differential codebook, where the differential codebook is a subband adjacent to the second subband group The codeword mapping of the group is obtained; the transmitting end selects a codeword of the second subband group from the differential codebook, and determines a differential PMI of the second subband group according to the codeword of the second subband group, that is, The differential PMI of the codeword of the second subband group in the differential codebook is used as the PMI of the second subband group. Or determining, by the transmitting end, the differential PMI of the second sub-band group may include the following steps: the transmitting end determines, from the differential codebook, a differential precoding matrix indication of the second sub-band group, where the differential codebook is The codeword mapping corresponding to the adjacent subband group of the second subband group is obtained.

The first sub-band group and the second sub-band group are relatively speaking. In this embodiment, the PMI of the second sub-band group is obtained by recursively starting from the PMI of the first sub-band group. Therefore, the first sub-band group may also be referred to as a starting sub-band group, a reference sub-band group, a basic sub-band group, an absolute sub-band group, etc.; accordingly, the second sub-band group may be referred to as a difference molecular band group, and a relative The subband group is relative to the first subband group.

In this implementation manner, the PMI of the second sub-band group is obtained by recursively starting from the PMI of the first sub-band group, and may include the following steps:

The transmitting end selects the codeword of the first subband group from the differential codebook corresponding to the reference codebook or the wideband codeword, and the absolute PMI of the codeword of the first subband group in the reference codebook or at the difference The differential PMI in the codebook is used as the PMI of the first subband group;

The transmitting end determines a differential codebook corresponding to the codeword of the first subband group, and selects a codeword of the second subband group adjacent to the first subband group from the determined differential codebook, and the second sub The differential PMI of the codeword of the group in the differential codebook is used as the PMI of the second subband group;

The transmitting end determines a differential codebook corresponding to the codeword of the second subband group, and selects, from the determined differential codebook, a codeword of another second subband group adjacent to the second subband group, The differential PMI of the codeword of the two subband group in the differential codebook is used as the PMI of the second subband group;

Etc., and so on, until the PMI of all second subband groups in the wideband is determined.

It can be seen that, in the above recursive process, the codeword and the differential PMI of the second subband group are selected from the differential codebook corresponding to the codeword of the subband group adjacent thereto. For the convenience of the description, in the embodiment of the present application, the differential codebook corresponding to the codeword of a subband group is simply referred to as a differential codebook of a subband group, and correspondingly, the differential codebook of a subband group refers to the differential codebook. The differential codebook corresponding to the codeword of the subband group. Specifically, the recursive process may include the following examples:

In one example, assuming the broadband includes a first subband group, then:

For a second subband group in the broadband that identifies an identifier smaller than the first subband group, the codeword and the differential PMI of the second subband group are adjacent to the second subband group and are smaller than the second subband group Selected in the differential codebook of the subband group with a large identification of the group;

Correspondingly, for the second subband group in the broadband that is greater than the identifier of the first subband group, the codeword and the differential PMI of the second subband group are adjacent to and adjacent to the second subband group. The second sub-band group is selected from the differential codebook of the small sub-band group.

In another example, it is assumed that the wideband includes two first subband groups and the identifier of one of the first subband groups is smaller than the identifier of the other first subband group, and the first subband group with the smaller one of the two is identified. Recorded as the first sub-band group A, the first sub-band group with the larger logo is recorded as the first sub-band group B, then:

For a second subband group in the broadband that identifies an identifier smaller than the first subband group A, the codeword and the differential PMI of the second subband group are adjacent to the second subband group and are smaller than the second subband group Selected in the differential codebook of the subband group with a large identification of the group;

For a second subband group in the broadband that identifies an identifier greater than the first subband group A and smaller than the identifier of the first subband group B, the codeword and the differential PMI of the second subband group are from the second subband Selected from a differential codebook of adjacent subband groups that are larger than the identity of the second subband group;

Correspondingly, for the second sub-band group in the broadband that identifies the identifier greater than the first sub-band group B, the codeword and the differential PMI of the second sub-band group are adjacent to and adjacent to the second sub-band group. The second sub-band group is selected from the differential codebook of the small sub-band group.

Optionally, for the second sub-band group in the broadband that identifies the identifier that is greater than the identifier of the first sub-band group A and smaller than the identifier of the first sub-band group B, the codeword and the differential PMI of the second sub-band group may also be The second subband group is selected in a differential codebook adjacent to and smaller than the identifier of the second subband group. That is, for the second sub-band group that identifies the identifiers between the two first sub-band groups, whether the first sub-band group with the smaller identifier is used as the recursion, or the first one with the larger identifier The subband group is the initial recursion and can be determined by signaling, advance agreement, or as specified by the protocol.

It can be seen that, in the above recursive process, the codeword and the differential PMI of the second subband group are obtained from the first subband group as a starting recursion, and the specific recursion manner is not limited to the above example.

In still another optional implementation manner, the PMI of the second subband group is a differential PMI determined based on the differential codebook, but different from the previous embodiment, the differential codebook is a difference corresponding to the wideband codeword. Codebook. That is to say, in this embodiment, the codewords and differential PMIs of all the subband groups in the wideband are selected from the differential codebooks corresponding to the wideband codewords.

In this implementation manner, the transmitting end determines the differential PMI of each subband group based on the broadband differential codebook, and may include the following steps: the transmitting end determines the differential codebook, where the differential codebook is obtained by wideband codeword mapping, and the broadband code is obtained. The word is selected from the reference codebook according to the measured broadband channel information; the transmitting end selects the codeword of each subband group from the differential codebook; and then; the codeword of each subband group is in the differential codebook The differential PMI is used as the PMI for each subband group.

In the above various embodiments for determining the differential PMI, if the differential PMI corresponding to the wideband codeword is used to determine the differential PMI, the transmitting end needs to transmit the PMI of the broadband in addition to the PMI of each subband group, so that the receiving The terminal can determine the codeword of the broadband according to the PMI of the broadband, and further determine the differential codebook according to the codeword of the broadband, to further determine the codeword corresponding to the differential PMI of the first subband group, or the second The codeword for the differential PMI of the subband group.

It can be seen that the PMIs of the first sub-band group and the second sub-band group are not necessarily determined in the same manner. Therefore, in addition to knowing the PMI of each sub-band group, the transmitting end and the receiving end need to know which of the sub-band groups are the first. A subband group and a second subband group are used to determine the codeword or PMI of the first subband group and to determine the codeword or PMI of the second subband group using the above alternative embodiments. Therefore, in an optional implementation manner, the first sub-band group may be predefined, or may be notified by downlink signaling, or reported by the uplink signaling after being measured by the channel. For example, the sub-band group with the smallest or the largest identification may be identified by the predefined first sub-band group, or the sub-band group with the middle of the sub-band group included in the broadband. For example, the first sub-band group notified by the downlink signaling is the sub-band group corresponding to the identifier carried in the downlink signaling. For example, the first sub-band group reported by the uplink signaling after the channel measurement is the sub-band group corresponding to the identifier carried in the uplink signaling, and so on. The first sub-band group reported by the uplink signaling after the channel measurement may be the sub-band group whose channel information is closest to the channel information of the broadband.

Since the subband group may include one subband or multiple subbands. When the subband group includes multiple subbands, the plurality of subbands may be a bounding relationship, so the first subband group may be determined by notifying the identifier of the subband included in the first subband group. For example, the pre-defined first sub-band group may be the sub-band group with the smallest identifier of the included sub-band or the sub-band of the included sub-band, or the sub-band group with the identifier of the included sub-band, the sub-band The identification of the middle means that the identity of the sub-band is centered in the identity of all sub-bands contained in the broadband. For example, the first sub-band group notified by the downlink signaling is a sub-band group formed by the sub-band corresponding to the identifier of the sub-band carried in the downlink signaling. For example, the first sub-band group reported by the uplink signaling after the channel measurement is a sub-band group formed by the sub-band corresponding to the identifier of the sub-band carried in the uplink signaling, and the like.

In an optional implementation manner, the precoding matrix indication information sent by the transmitting end includes a differential precoding matrix indication, which is predefined, or is notified by downlink signaling, or is determined by the uplink signaling after channel measurement. The reporting is performed, so that after receiving the precoding matrix indication information, the receiving end can determine the codeword corresponding to each subband group.

Further, as can be seen from the above, the manner of determining the PMI of the first sub-band group and the second sub-band group includes various implementation manners, and the following three implementation manners are as follows:

Embodiment 1: The PMI of the first sub-band group and the PMI of the second sub-band group are both differential PMIs determined based on the broadband differential codebook.

Embodiment 2: The PMI of the first sub-band group is a differential PMI determined based on the differential codebook of the broadband, and the PMI of the second sub-band group is a differential PMI determined based on the differential codebook of the sub-band group adjacent thereto;

Embodiment 3: The PMI of the first sub-band group is an absolute PMI determined based on the reference codebook, and the PMI of the second sub-band group is a differential PMI determined based on the differential codebook of the sub-band group adjacent thereto;

Therefore, for the foregoing three implementation manners, the transmitting end needs to notify the receiving end of the implementation manner of the foregoing precoding matrix indication information. For example, the indication information may be used to indicate an implementation corresponding to the PMI in the precoding matrix indication information sent by the transmitting end. For example, in order to indicate the above three implementation manners, the indication information requires 3 bits, 00 represents Embodiment 1, 01 represents

Embodiment

2, and 10 represents Embodiment 3. Optionally, 11 means that each PMI is an absolute PMI. Accordingly, it is possible to predefine which implementation is used to determine the PMI. When the PMI is determined by the downlink signaling, the indication information may be carried in the downlink signaling. Or, when the channel is measured and reported by the uplink signaling, which embodiment is used to determine the PMI, the uplink signaling may carry the indication information.

In an optional implementation manner, the differential codebook is mapped from the reference codebook, and includes: the differential codebook includes a codeword that satisfies a preset rule from the reference codebook. Selected in the code word. The codeword that satisfies the preset rule is a codeword whose distance from the target codeword is within a preset distance, or a codeword that satisfies a preset condition with a correlation between the target codeword, or is The beam code of the target codeword is subjected to a differential operation to select a codeword.

The target codeword is a wideband codeword or a codeword of a subband group adjacent to the second subband group, and the subband group adjacent to the second subband group may be the first subband group or the second Subband group.

Wherein, when the difference between the beam coefficients of the target codeword is performed to determine the differential codebook corresponding to the target codeword, the difference operation may be a difference operation between the wideband coefficient and the narrowband coefficient in the beam coefficient as a whole, or may be The phase parameter of the beam coefficient is subjected to a difference operation, that is, the wideband coefficient and the narrowband coefficient are separately subjected to a difference operation, and the phase parameter is also subjected to a difference operation.

The foregoing optional embodiment describes how to determine the differential codebook corresponding to the target codeword. However, how to determine the differential codebook corresponding to the target codeword in the embodiment of the present application is not limited to the foregoing embodiment. Optionally, the differential codebook corresponding to each codeword in the reference codebook may be specified by the protocol, and both the receiving end and the transmitting end are known, so that the transmitting end and the receiving end determine the codeword, and the table can be checked. In the manner of obtaining the differential codebook corresponding to the codeword, the processing complexity of the transmitting end and the receiving end can be reduced. The codewords included in the differential codebook may be determined based on the above embodiments, and the differential PMI corresponding to each codeword may be determined based on the corresponding absolute PMI of the codeword in the reference codebook.

In an optional implementation manner, the differential PMI of each codeword included in the differential codebook corresponds to an absolute PMI of each codeword in ascending or descending order. For example, if the differential codebook includes four codewords, the number of bits required for the differential PMI in the differential codebook is 2 bits, and the difference PMI in the differential codebook is 00, 01, 10, and 11, respectively. The difference PMI of each codeword of the differential codebook corresponds to the absolute PMI of each codeword after the ascending order, and the codewords corresponding to 00, 01, 10, and 11 respectively are codewords whose absolute PMI is from small to large; The difference PMI of each codeword of the differential codebook corresponds to the absolute PMI of the codewords after the descending order, and the codewords corresponding to 00, 01, 10, and 11 respectively are absolute PMI codewords from large to small. .

In an optional implementation manner, the number of codewords M included in the differential codebook is related to the overhead size and system performance, that is, the larger the M, the bit indicating the precoding matrix of the codeword in the differential codebook indicates the required bit. The more the number, the larger the signaling overhead, but the number of optional codewords in the differential codebook is more, and the more codewords are available for each subband group, so the system performance is better; correspondingly, M The smaller the indication, the smaller the number of bits required to indicate the precoding matrix of the codeword in the differential codebook, and the smaller the signaling overhead, but the number of optional codewords in the differential codebook is smaller, and each subband group The fewer optional codewords, the system performance is relatively poor. Therefore, the value of the compromise can be selected under the balance of signaling overhead and system performance. For example, when M=2, the precoding matrix indication in the differential codebook only needs 1 bit, M=4, and the difference codebook The precoding matrix indication requires 2 bits. For example, when the precoding matrix indicating the codeword included in the differential codebook indicates that the number of bits required for the differential PMI of the differential codebook is 1-4 bits, the system performance can be improved while the signaling overhead is reduced.

On the other hand, the embodiment of the present application further provides a precoding matrix indication method, which is described by the receiving end as an execution body, and may include the following steps: the receiving end receives at least one first subband group. Precoding matrix indication and precoding matrix indication of at least one second subband group; said receiving end determining said at least one first from a reference codebook according to an absolute precoding matrix indication of said at least one first subband group a codeword of the subband group or a codeword indicating the at least one first subband group from the differential codebook according to the differential precoding matrix of the at least one first subband group; and according to the at least one second The precoding matrix of the subband group indicates determining a codeword of the at least one second subband group from the differential codebook; the differential codebook is mapped from the reference codebook. It can be seen that, in this embodiment of the present application, each subband group has a corresponding absolute PMI or a differential PMI, and the precoding matrix used in the subbands in the same subband group is the same, and the precoding matrix used in each subband group may be different. Therefore, the anti-interference ability between each sub-band group can be improved, and the spectrum efficiency and system performance of the system are greatly improved.

The receiving end determines, according to the differential precoding matrix of the at least one first subband group, the codeword of the at least one first subband group from the differential codebook, where there are two cases, one, when the differential codebook For each differential PMI, corresponding to a partial codeword in the reference codebook, the receiving end may directly determine the codeword of the at least one first subband group from the differential codebook according to the differential PMI of the at least one first subband group; Alternatively, when each differential PMI in the differential codebook corresponds to a partial absolute PMI in the reference codebook, the receiving end may first determine at least one of the differential codebooks according to the differential PMI of the at least one first subband group. The absolute PMI of the first subband group, and then determining the codeword of the at least one first subband group from the reference codebook according to the absolute PMI of the at least one first subband group.

Correspondingly, the receiving end determines, according to the differential precoding matrix of the at least one second subband group, the codeword of the at least one second subband group from the differential codebook, where there are two cases, one, when the differential code If the differential PMI is corresponding to the partial codeword in the reference codebook, the receiving end may directly determine the codeword of the at least one second subband group from the differential codebook according to the differential PMI of the at least one second subband group. Alternatively, when each differential PMI in the differential codebook corresponds to a partial absolute PMI in the reference codebook, the receiving end may first determine at least the differential codebook according to the differential PMI of the at least one second subband group. An absolute PMI of a second subband group, and then determining a codeword of the at least one second subband group from the reference codebook according to an absolute PMI of the at least one second subband group.

In an optional implementation manner, the precoding matrix indication method further includes: the receiving end acquires a wideband codeword; the receiving end determines a differential codebook mapped by the wideband codeword, and the differential codebook As a differential codebook used to determine a codeword of the at least one first subband group. That is, the receiving end may determine the codeword of the first subband group according to the differential PMI of the first subband group and the differential codebook of the wideband. The wideband codeword is determined by the receiving end according to the absolute PMI and the reference codebook that the transmitting end sends the broadband.

In an optional implementation manner, the precoding matrix indication method further includes: for each second subband group in the at least one second subband group, the receiving end acquires the second sub a codeword with a group of adjacent subbands; the receiving end determines a differential codebook to which the codewords of the adjacent subband group are mapped, and the differential codebook is used as the second subband group The differential codebook used by the codeword. That is, the receiving end may determine the codeword of the second subband group according to the differential PMI of the second subband group and the differential codebook of the subband group adjacent to the second subband group. The codeword of the second subband group is obtained by recursively starting from the codeword of the first subband group.

Specifically, the codeword of the second subband group is obtained by recursively starting from the codeword of the first subband group, and may include the following steps:

The receiving end determines the codeword of the first subband group from the reference codebook according to the absolute PMI of the first subband group, or determines the first subband group from the broadband differential codebook according to the differential PMI of the first subband group. numbers;

The receiving end determines a differential codebook of the codeword of the first subband group, and determines the first part from the differential codebook of the first subband group according to the difference PMI of the second subband group adjacent to the first subband group The code word of the two sub-band group;

The receiving end determines a differential codebook of the codeword of the second subband group, and according to the difference PMI of the further second subband group adjacent to the second subband group, from the differential codebook of the second subband group Determining a codeword of the further second sub-band group;

Etc., and so on, until the codewords of all second subband groups in the wideband are determined.

It can be seen that, in the above recursive process, the codeword of the second subband group is determined according to the differential PMI of the second subband group and the differential codebook of the subband group adjacent thereto. Specifically, the recursive process may include the following examples:

In one example, assuming the broadband includes a first subband group, then:

For a second subband group in the broadband that identifies an identifier smaller than the first subband group, the codeword of the second subband group is adjacent to the second subband group according to its own differential PMI The two sub-band groups are identified in the differential codebook of the large sub-band group;

Correspondingly, for the second sub-band group in the broadband that is greater than the identifier of the first sub-band group, the codeword of the second sub-band group is adjacent to the second sub-band group according to its own differential PMI. Determined in the differential codebook of the subband group smaller than the identification of the second subband group.

For the second subband group in the broadband that identifies the identifier smaller than the first subband group A, the codeword of the second subband group is adjacent to the second subband group according to its own differential PMI The two sub-band groups are identified in the differential codebook of the large sub-band group;

For the second subband group in the broadband that identifies the identifier larger than the first subband group A and smaller than the identifier of the first subband group B, the codeword of the second subband group is based on its own differential PMI from the second subband. Determining in the differential codebook of the subband group adjacent to the subband group and larger than the identifier of the second subband group;

Correspondingly, for the second subband group in the broadband that identifies the identifier larger than the first subband group B, the codeword of the second subband group is adjacent to the second subband group according to its own differential PMI. Determined in the differential codebook of the subband group smaller than the identification of the second subband group.

Optionally, for the second sub-band group in the broadband that identifies the identifier that is greater than the identifier of the first sub-band group A and smaller than the identifier of the first sub-band group B, the codeword of the second sub-band group may also be based on its own difference. The PMI is determined from a differential codebook of the subband group adjacent to the second subband group and smaller than the identity of the second subband group. That is, for the second sub-band group that identifies the identifiers between the two first sub-band groups, whether the first sub-band group with the smaller identifier is used as the recursion, or the first one with the larger identifier The subband group is the initial recursion and can be determined by signaling, advance agreement, or as specified by the protocol.

It can be seen that, in the above recursive process, the codewords of the second subband group are obtained from the first subband group as the initial recursion, and the specific recursion manner is not limited to the above example.

In still another optional implementation manner, the codeword of the second subband group is determined from the differential codebook corresponding to the wideband codeword according to its own differential PMI. For example, the codewords of all the subband groups in the broadband are determined from the differential codebook corresponding to the wideband codeword according to its own differential PMI.

The receiving end determines the codeword of each subband group based on the broadband differential codebook, and may include the following steps: the receiving end determines the differential codebook, where the differential codebook is obtained by wideband codeword mapping, and the broadband codeword is based on The absolute PMI of the broadband is determined from the reference codebook; the transmitting end determines the codeword of each subband group from the differential codebook according to the differential PMI of each subband group.

In the implementation manner of the foregoing various codewords, if a differential codebook corresponding to a wideband codeword is used, the transmitting end needs to send a broadband PMI in addition to the PMI of each subband group, so that the receiving end can The wideband codeword is determined according to the wideband PMI, and the differential codebook is determined according to the wideband codeword to further determine the codeword of the first subband group, or the codeword of the second subband group.

In an optional implementation manner, the first sub-band group is predefined, or is notified by downlink signaling, or is reported by the uplink signaling after being measured by the channel.

In an optional implementation manner, the differential codebook is mapped from the reference codebook, and includes: the differential codebook includes a codeword that satisfies a preset rule from the reference codebook. Selected in the code word.

In an optional implementation manner, the codeword that satisfies the preset rule is a codeword whose distance from the target codeword is within a preset distance, or the correlation with the target codeword satisfies the preset. Conditional codeword.

In an optional implementation manner, the differential codebook is mapped from the reference codebook, and includes: the differential codebook includes a codeword that is a beam of codewords in the reference codebook. The coefficients are obtained by differential operation.

In an optional implementation manner, the target codeword is a broadband codeword or a codeword of a subband group adjacent to the second subband group.

In an optional implementation manner, the differential precoding matrix of each codeword included in the differential codebook indicates an absolute precoding matrix indication of each of the codewords after ascending or descending order.

In an optional implementation manner, a beam coefficient of a codeword in the differential codebook is obtained by performing a differential operation on a beam coefficient of a codeword in the reference codebook.

In an optional implementation manner, the difference codebook includes a differential PMI having a bit number of 1-4 bits.

In an optional implementation manner, the precoding matrix indication information sent by the transmitting end includes a differential precoding matrix indication, which is predefined, or is notified by downlink signaling, or is uplinked after channel measurement. Signaling is reported.

In this aspect, related content of the foregoing content may refer to related content described in the first aspect, and details are not described herein.

In another aspect, the embodiment of the present invention further provides a device, which has some or all functions of the transmitting end or the receiving end in the foregoing method example, for example, the function of the device may be provided in some or all of the embodiments in this application. The functions may also be provided with the functions of any of the embodiments of the present application. The functions may be implemented by hardware or by corresponding software implemented by hardware. The hardware or software includes one or more units or modules corresponding to the functions described above.

In one possible design, the processing unit and the communication unit may be included in the structure of the device, the processing unit being configured to support the terminal device to perform a corresponding function in the above method. The communication unit is used to support communication between the terminal device and other devices. The terminal device may further comprise a storage unit for coupling with the processing unit, which stores program instructions and data necessary for the terminal device. As an example, the processing unit can be a processor, the communication unit can be a transceiver, and the storage unit can be a memory.

In another aspect, the embodiment of the present invention provides a device, which may be a network device, and has some or all functions of the transmitting end and/or the receiving end in the foregoing method example, for example, the function of the device may have the part in this application. The functions in any of the embodiments may also be provided with the functions of any of the embodiments of the present application. The functions may be implemented by hardware or by corresponding software implemented by hardware. The hardware or software includes one or more units or modules corresponding to the functions described above.

In one possible design, the structure of the device includes a processing unit and a communication unit, the processing unit being configured to support the transmitting end and/or the receiving end to perform corresponding functions in the above methods. The communication unit is used to support communication between the device and other devices. The apparatus may also include a storage unit for coupling with the processing unit that holds program instructions and data necessary for the device. As an example, the processing unit can be a processor, the communication unit can be a transceiver, and the storage unit can be a memory.

In another aspect, an embodiment of the present invention provides a communication system, where the system includes a transmitting end and a receiving end of the foregoing aspect. In another possible design, the system may further include other devices that interact with the transmitting end and/or the receiving end in the solution provided by the embodiment of the present invention.

In still another aspect, an embodiment of the present invention provides a computer storage medium for storing computer software instructions for use by the transmitting end, including a program designed to perform any of the above methods.

In another aspect, an embodiment of the present invention provides a computer storage medium for storing computer software instructions for use by the receiving end, including a program designed to perform any of the above methods.

In yet another aspect, the present application also provides a computer program product comprising instructions which, when run on a computer, cause the computer to perform the methods described in the various aspects above.

In yet another aspect, the present application provides a chip system including a processor for supporting functions involved in the above aspects of the final transmitting end and/or the receiving end, for example, determining or processing the methods involved in the above method. Data and / or information. In a possible design, the chip system further comprises a memory for storing the necessary program instructions and data at the transmitting end and/or the receiving end. The chip system can be composed of chips, and can also include chips and other discrete devices.

In yet another aspect, the present application provides a chip system including a processor for supporting a transmitting end and/or a receiving end to implement the functions involved in the above aspects, for example, generating or processing the methods involved in the above method. Data and / or information. In a possible design, the chip system further comprises a memory for storing the necessary program instructions and data at the transmitting end and/or the receiving end. The chip system can be composed of chips, and can also include chips and other discrete devices.

DRAWINGS

1a is a schematic diagram of a broadband included subband group provided by an embodiment of the present application;

1b is a schematic diagram of another broadband included subband group provided by an embodiment of the present application;

2 is a schematic structural diagram of a communication system according to an embodiment of the present application;

3 is a schematic flowchart of a method for indicating a precoding matrix according to an embodiment of the present application;

FIG. 4 is a schematic flowchart diagram of another precoding matrix indication method according to an embodiment of the present application.

FIG. 5 is a schematic structural diagram of an apparatus according to an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of another device according to an embodiment of the present disclosure.

FIG. 7 is a schematic structural diagram of a terminal device according to an embodiment of the present disclosure;

FIG. 8 is a schematic structural diagram of another apparatus according to an embodiment of the present disclosure;

FIG. 9 is a schematic structural diagram of a network device according to an embodiment of the present application.

Detailed ways

The terms used in the embodiments of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application.

The precoding matrix indication method uses a differential precoding matrix indicator (PMI) to indicate a code. The word, the precoding matrix, can reduce the signaling overhead compared to the way that absolute PMI is currently used to indicate the codeword.

In the embodiment of the present application, the absolute precoding matrix indication (ie, absolute PMI) is an index or label of the codeword in the reference codebook, and may also be referred to as a reference PMI, a basic PMI, etc.; a differential precoding matrix indication (ie, a differential PMI). It is the index or label of the codeword in the differential codebook, which can also be called the relative PMI. Codewords can also be referred to as precoding matrices.

In an optional implementation manner, the mapping of the differential codebook from the reference codebook refers to that the codeword included in the differential codebook is selected from codewords in the reference codebook that satisfy a preset rule. Therefore, the number of codewords included in the differential codebook is smaller than the number of codewords included in the reference codebook, so the number of bits of the differential PMI of the same codeword in the differential codebook is smaller than the absolute PMI of the codeword in the reference codebook. The number of bits. Therefore, in the embodiment of the present application, the manner in which the transmitting end uses the differential PMI to indicate the codeword can reduce the signaling overhead compared with the manner in which the absolute PMI is used to indicate the codeword. In addition, in this embodiment of the present application, each subband group has a corresponding absolute PMI or a differential PMI, and the precoding matrix used in the subbands in the same subband group is the same, and the precoding matrix used in each subband group may be different. Therefore, the anti-interference ability between each sub-band group can be improved, and the spectrum efficiency and system performance of the system are greatly improved.

The codeword that satisfies the preset rule is a codeword whose distance from the target codeword is within a preset distance, that is, the distance between each codeword in the reference codebook and the target codeword is calculated, and the codeword is selected therefrom. The codeword within the preset distance or the smallest distance constitutes a differential codebook of the target codeword. Wherein, the distance refers to a norm after subtracting two codewords. Or, the codeword that satisfies the preset rule is a codeword that satisfies a preset condition with a correlation between the target codeword, that is, calculates a correlation between each codeword in the reference codebook and the target codeword, Selecting the most relevant codeword constitutes the differential codebook of the target codeword. Wherein, the correlation refers to the correlation coefficient between two codewords, and the correlation coefficient is between the intervals 0 and 1. The closer the correlation coefficient of the two codewords is to 1, indicating that the correlation between the two codewords is greater. .

In another optional implementation manner, the codeword in the differential codebook is obtained by performing differential operation on the beam coefficients of the codewords in the reference codebook. For example, a difference operation is performed on a beam coefficient of a target codeword, and a codeword of a beam coefficient closest to a beam coefficient obtained by the difference operation is selected from a reference codebook to constitute a differential codebook of the target codeword.

The reference codebook is a codebook specified in the protocol, and the codebook can be obtained by both the transmitting end and the receiving end. Currently, there are two types of reference codebooks in the downlink system, which are called type I (type I) and type II (type II). For the type I type reference codebook, determining the subband group beam is to adjust the determined broadband or adjacent subband group beam to obtain a new beam, and for the type II type reference codebook, determining the subband The beam of the group is adjusted for the beam coefficients of the beam of the broadband or adjacent sub-band group, and the same beam is obtained. In the uplink system, the reference codebook may be a single-level codebook, that is, one codeword is selected from the single-stage codebook for uplink transmission on the broadband. The broadband may be an uplink full bandwidth channel or a bandwidth scheduled by the terminal device. The reference codebook described in the embodiment of the present application may include the codebook of the foregoing type, but is not limited to the codebook of the foregoing type, that is, other codebooks specified by the protocol may be used as the standard evolves.

In the embodiment of the present application, the number of codewords included in the differential codebook may be selected according to a balance between signaling overhead and system performance, and the value may be 2, 4, 8, etc., such as M. When =2, the differential PMI in the differential codebook only needs 1 bit; M=4, and the differential PMI in the differential codebook requires 2 bits. For example, when the number of bits required for the differential PMI of the differential codebook is 1-4 bits, it is possible to improve system performance while reducing signaling overhead.

The differential PMI corresponding to each codeword in the differential codebook may be determined based on the corresponding absolute PMI of the codeword in the reference codebook. In an optional implementation manner, the differential PMI of each codeword included in the differential codebook corresponds to an absolute PMI of each codeword in ascending or descending order. For example, if the differential codebook includes four codewords, the number of bits required for the differential PMI in the differential codebook is 2 bits, and the difference PMI in the differential codebook is 00, 01, 10, and 11, respectively. The difference PMI of each codeword of the differential codebook corresponds to the absolute PMI of each codeword after the ascending order, and the codewords corresponding to 00, 01, 10, and 11 respectively are codewords whose absolute PMI is from small to large; The difference PMI of each codeword of the differential codebook corresponds to the absolute PMI of each codeword after the descending order, and the codewords corresponding to 00, 01, 10, and 11 respectively are codewords corresponding to the absolute PMI from large to small. .

The embodiment of the present application takes the reference codebook as a single-level codebook and a type II codebook as an example to illustrate how to obtain a differential codebook corresponding to the target codeword from the reference codebook. In this embodiment, the target codeword may be any codeword in the reference codebook, and the target codeword used by the transmitting end to determine the PMI of each subband group may be a broadband codeword or a second sub-word. A codeword with a group of adjacent subbands. The codeword of the subband group adjacent to the second subband group may be the codeword of the first subband group or the codeword of the other second subband group.

The example one reference codebook is a single-level codebook, and the codebook included in the differential codebook is selected from the codewords in which the distance between the reference codebook and the target codeword is the smallest.

Referring to Table 1, Table 1 provides an optional precoding matrix for single layer transmission using four antenna ports according to an embodiment of the present application. As shown in Table 1, each codeword in the table has a corresponding precoding matrix indication, and the precoding matrix indicates that the codewords are gradually increased from left to right and correspond to the codewords from left to right, that is, a PMI corresponding A code word. For example, if the PMI is 0, the corresponding codeword is 1/2[1 0 0 0] ^{T. When the} PMI is 1, the corresponding codeword is 1/2[0 1 0 0] ^{T. When the} PMI is 2, the corresponding codeword is 1/2[0 0 1 0] ^T , and so on.

Table 1

The PMI of the codeword in Table 1 is called absolute PMI, and each codeword in the table 1 has a corresponding differential codebook, and the differential codebook can be designed in various ways, for example, considering the distance between codewords. , relevance, etc.

For example, when considering a differential codebook corresponding to a codeword with an absolute PMI of 15, assuming that the differential codebook includes four codewords, the distance from the reference codebook shown in Table 1 to the codeword with an absolute PMI of 15 is the shortest. The three codewords can be, the distance between the two codewords is the norm after subtracting the two codewords. For example, the norm between the two matrices of codeword x1 and codeword x2 is | |x1-x2||. Therefore, each codeword in Table 1 can be calculated with a codeword with an absolute PMI of 15, that is, a norm between 1/2[1 1 -j -j] ^T , from which the smallest four codewords are selected, such as absolute PMIs are code words of 12, 15, 17 and 18, respectively 1/2[1 1 1 -1] ^T , 1/2[1 1 -j -j] ^T , 1/2[1 j j 1] ^T , 1/2[1 j –1 -j] ^T .

Assuming that the differential codebook includes four codewords, the identifier of each codeword in the differential codebook, that is, the difference PMI is 00, 01, 10, and 11 from small to large, assuming the difference of each codeword of the differential codebook. The PMI corresponds to the absolute PMI of each codeword after the ascending order, and the differential PMIs: 00, 01, 10, and 11, respectively, correspond to absolute PMIs: 12, 15, 17, and 18.

Therefore, the correspondence between the differential PMI and the codeword in the differential codebook can be as shown in Table 2 below.

Table 2 Differential codebook corresponding to absolute PMI15

差分PMIDifferential PMI	0000	0101	1010	1111
预编码矩阵(码字)Precoding matrix (codeword)	1/2[1 1 1 -1] ^T 1/2[1 1 1 -1] ^T	1/2[1 1 –j -j] ^T 1/2[1 1 –j -j] ^T	1/2[1 j j 1] ^T 1/2[1 j j 1] ^T	1/2[1 j –1 -j] ^T 1/2[1 j –1 -j] ^T

Alternatively, the correspondence between the differential PMI and the absolute PMI in the differential codebook can be as shown in Table 3 below.

table 3

差分PMIDifferential PMI	0000	0101	1010	1111
绝对PMIAbsolute PMI	1212	1515	1717	1818

In another example, assuming that the difference PMI of each codeword of the differential codebook corresponds to the absolute PMI of the codewords after the descending order, the differential PMIs: 00, 01, 10, and 11, respectively, correspond to absolute PMIs. : 18, 17, 15 and 12.

Therefore, the correspondence between the differential PMI and the codeword in the differential codebook can be as shown in Table 4 below.

Table 4 Differential codebook corresponding to absolute PMI15

差分PMIDifferential PMI	0000	0101	1010	1111
预编码矩阵(码字)Precoding matrix (codeword)	1/2[1 j –1 -j] ^T 1/2[1 j –1 -j] ^T	1/2[1 j j 1] ^T 1/2[1 j j 1] ^T	1/2[1 1 –j -j] ^T 1/2[1 1 –j -j] ^T	1/2[1 1 1 -1] ^T 1/2[1 1 1 -1] ^T

Alternatively, the correspondence between the differential PMI and the absolute PMI in the differential codebook can be as shown in Table 5 below.

table 5

差分PMIDifferential PMI	0000	0101	1010	1111
绝对PMIAbsolute PMI	1818	1717	1515	1212

It can be seen that, as shown in Tables 2, 3, 4, and 5, the number of bits of the corresponding differential PMI of the same codeword in the differential codebook is much smaller than the corresponding absolute PMI of the codeword in the reference codebook, and therefore, the transmission The precoding matrix indication information sent by the terminal includes a differential PMI, which can reduce the signaling overhead compared with the absolute PMI that feeds back the same number of codewords.

The example two reference codebook is a codebook of type II, and the codeword included in the differential codebook is obtained by performing differential operation on the beam coefficients of the target codeword.

The type II codebook is expressed as follows:

Where L denotes a total of L beam combinations, p ^(WB) is a broadband amplitude coefficient, the amplitude coefficient is represented by 3 bits; p ^(SB) is a narrow band amplitude coefficient, and the amplitude coefficient is represented by 1 bit ;c is the phase coefficient. If it is Quadrature Phase Shift Keyin (QPSK), it needs 2 bits to represent. If it is 8QPSK, the phase coefficient needs to be represented by 3 bits.

It is assumed that the codeword included in the differential codebook is obtained by performing a difference operation on the amplitude coefficient of the wideband of the target codeword and the amplitude coefficient of the narrowband as a whole, that is, the amplitude coefficient of the target codeword; the size of the differential codebook is Include 4 code words, that is, a differential PMI requires 2 bits to represent each codeword; and the target codeword is a codeword selected by the transmitting end to measure channel information of the first subband group from the reference codebook, the codeword The amplitude coefficient is 1, and the amplitude coefficients obtained by performing the difference operation on the amplitude coefficient are respectively

Correspondingly, the four codewords whose amplitude coefficients are closest to the amplitude coefficients in the reference codebook may constitute a differential codebook of the amplitude coefficients of the target codeword. Correspondingly, the differential PMI of the four codewords can be more accurate than 00, 01, 10, and 11 using the same wideband amplitude coefficients for all narrowbands in the narrowband feedback.

It is assumed that the codeword included in the differential codebook is obtained by performing a difference operation on the phase coefficient of the target codeword, and the differential codebook includes four codewords, that is, the differential PMI requires 2 bits to represent each codeword; The absolute phase coefficient is exp(j(phi)), and the absolute phase coefficient is 8psk; based on the absolute phase coefficient, the angle is rotated according to a certain step size (delta_phi), and the obtained four phase coefficients are:

[exp(j(phi-delta_phi)) exp(j(phi)) exp(j(phi+delta_phi)) exp(j(phi+2*delta_phi))] or

[exp(j(phi-2*delta_phi)) exp(j(phi-delta_phi)) exp(j(phi)) exp(j(phi+delta_phi))]

The four phase coefficients are the differential PMI corresponding to the phase coefficients: 00 01 10 11, and the phase information of the differential precoding of the second subband group can be selected in this differential codebook.

In the embodiment of the present application, the broadband may include at least one first sub-band group and at least one second sub-band group, where the first sub-band group may be referred to as a starting sub-band group, a reference sub-band group, and a basic sub-band group. The absolute sub-band group, etc., the second sub-band group may be referred to as a difference molecular band group or a relative sub-band group, relative to the first sub-band group. The first subband group and the second subband group are different in that the codewords of the two are selected from different codebooks, and the codewords of the first subband group are based on channel information of the first subband group. Selected from the reference codebook, or selected from a differential codebook corresponding to the wideband codeword; and the codeword of the second subband group is a code from the subband group adjacent to the second subband group The word is selected in the differential codebook. The first sub-band group and the second sub-band group each include at least one sub-band.

Since the channel has a certain channel correlation in the frequency domain, for example, the correlation between adjacent sub-band groups is relatively high, and the channel difference is correspondingly small. Therefore, on the one hand, the second sub-band group The codeword is selected from the differential codebook of the subband group adjacent to the second subband group to more accurately approximate the channel. On the other hand, selecting the codeword from the differential codebook can feed back the differential PMI when feeding back the PMI, thereby Reduce the overhead of signaling.

In an optional implementation manner, the first sub-band group may be predefined, or notified by downlink signaling, or reported by uplink signaling after channel measurement. For example, the sub-band group with the smallest or the largest identification may be identified by the predefined first sub-band group, or the sub-band group with the middle of the sub-band group included in the broadband. For example, the first sub-band group notified by the downlink signaling is the sub-band group corresponding to the identifier carried in the downlink signaling. For example, the first sub-band group reported by the uplink signaling after the channel measurement is the sub-band group corresponding to the identifier carried in the uplink signaling, and so on. The first sub-band group reported by the uplink signaling after the channel measurement may be the sub-band group whose channel information is closest to the channel information of the broadband.

Since the subband group may include one subband or multiple subbands. When the subband group includes multiple subbands, the plurality of subbands may be a bounding relationship, so the first subband group may be determined by notifying the identifier of the subband included in the first subband group. For example, the pre-defined first sub-band group may be the sub-band group with the smallest identifier of the included sub-band or the sub-band of the included sub-band, or the sub-band group with the identifier of the included sub-band, the sub-band The identification of the middle means that the identity of the sub-band is centered in the identity of all sub-bands contained in the broadband. For example, the first sub-band group notified by the downlink signaling is a sub-band group formed by the sub-band corresponding to the identifier of the sub-band carried in the downlink signaling. For example, the first sub-band group reported by the uplink signaling after the channel measurement is a sub-band group corresponding to the sub-band corresponding to the identifier of the sub-band carried in the uplink signaling, and so on.

For example, please refer to FIG. 1a, which is a schematic diagram of partitioning of a sub-band group included in a broadband according to an embodiment of the present application. As shown in FIG. 1a, the broadband may include a plurality of sub-band groups, which are continuous sub-band groups, respectively sub-band group m-2, sub-band group m-1, sub-band group m, sub-band Group m+1, subband group m+2, subband group m+3, subband group m+4. In the broadband, the first first sub-band group is determined by the notification manner described above, which is a sub-band group m and a sub-band group m+3, and the other bands except the sub-band group m and the sub-band group m+3 The sub-band groups are respectively the second sub-band groups. Therefore, the identifiers m and m+3 of the sub-band group m and the sub-band group m+3 may be identifiers of the predefined first sub-band group, or identifiers carried by the uplink signaling, or identifiers carried by the downlink signaling. So that the transmitting end and the receiving end can know the identifier belonging to the first sub-band group.

For example, please refer to FIG. 1b. FIG. 1b is a schematic diagram of partitioning of a subband group included in another broadband provided by an embodiment of the present application. As shown in FIG. 1b, the broadband may include a plurality of subband groups, the plurality of subband groups being non-contiguous subband groups, that is, the subband group included in the broadband is a subband group m-2, and the subband group m-1 , subband group m, subband group m+2, subband group m+3, subband group m+4, wherein the broadband includes a first subband group, that is, the subband group m is the first subband group , subband group m-2, subband group m-1, subband group m+2, subband group m+3, subband group m+4, and subband group m+4 are respectively second subband group Wherein the broadband does not include the subband group m+1. Therefore, the identifier m of the sub-band group m can be an identifier of the predefined first sub-band group, or an identifier carried by the uplink signaling, or an identifier carried by the downlink signaling, so that the transmitting end and the receiving end can learn to belong to The identification of the subband group of the first subband group.

In the embodiment of the present application, when the subband group included in the broadband is a continuous subband group, the subband group adjacent to the subband group is the subband group adjacent to the identifier; when the subband group included in the broadband is In the case of non-contiguous sub-band groups, the sub-band groups adjacent to the sub-band group may be sub-band groups that are not adjacent to the identifier. As shown in FIG. 1b, the sub-band group m+2 may be adjacent to the sub-band group m. The sub-band group, that is, the adjacent sub-band group is the sub-band group of the sub-band group belonging to the broadband that is closest to the identification of the sub-band group.

The technical solution of the present application can be specifically applied to various communication systems, for example, Global System for mobile communications (abbreviation: GSM), Code Division Multiple Access (CDMA), and wideband code. Wideband Code Division Multiple Access (WCDMA), Time Division-Synchronous Code Division Multiple Access (TD-SCDMA), Universal Mobile Telecommunications System (abbreviation: UMTS), Long Term Evolution (LTE) system, etc. With the continuous development of communication technologies, the technical solution of the present application can also be applied to future networks, such as 5G systems, and can also be called New Radio. Abbreviation: NR) system, or can be used for D2D (device to device) system, M2M (machine to machine) system and so on.

The network device involved in the present application may refer to an entity on the network side for transmitting or receiving information, such as a base station, or may be a transmission point (TP), a transmission and receiver point (transmission and receiver point, Abbreviations: TRP), relay devices, or other network devices with base station functions, etc., which are not limited in this application.

In the present application, a terminal device or a terminal device is a device having a communication function, which may include a handheld device having a wireless communication function, an in-vehicle device, a wearable device, a computing device, or other processing device connected to a wireless modem, and the like. Terminal devices in different networks may be called different names, such as: terminal, terminal equipment (UE), mobile station, subscriber unit, relay relay, station, cellular telephone, personal digital assistant, wireless modem, Wireless communication devices, handheld devices, laptops, cordless phones, wireless local loop stations, and the like. The terminal device may refer to a wireless terminal or a wired terminal. The wireless terminal can be a device that provides voice and/or data connectivity to the user, a handheld device with wireless connectivity, or other processing device connected to the wireless modem, which can be accessed via a radio access network (eg, RAN, radio access) Network) communicates with one or more core networks.

In the present application, a base station, which may also be referred to as a base station device, is a device deployed in a wireless access network to provide wireless communication functions. The name of the base station may be different in different wireless access systems. For example, in a UMTS network, a base station is called a Node B (NodeB), and a base station in an LTE network is called an evolved Node B (abbreviated as an eNB or eNodeB), which may be referred to as a TRP network node or a g-NodeB (gNB) in the future 5G system, etc., is not enumerated here.

Please refer to FIG. 2. FIG. 2 is a schematic structural diagram of a communication system according to an embodiment of the present application. For convenience of description, the embodiment of the present application is illustrated by using FIG. 2 as an example. As shown in FIG. 2, the base station and the terminal device are respectively taken as an example.

Referring to FIG. 3, FIG. 3 is a schematic flowchart of a precoding matrix indication method according to an embodiment of the present disclosure, and the precoding matrix indication method illustrated in FIG. 3 is illustrated from an uplink system. As shown in FIG. 3, the precoding matrix indication method may include the following steps:

101. The base station selects a broadband codeword from the reference codebook according to the measured broadband channel information.

102. The base station determines a differential codebook corresponding to the codeword of the broadband;

For an alternative implementation manner in which the base station determines the differential codebook corresponding to the codeword of the broadband, reference may be made to the foregoing related content, which is not described in detail herein. The differential codebook corresponding to the wideband codeword is simply referred to as a wideband differential codebook. Correspondingly, the differential codebook corresponding to one codeword may be referred to as a differential codebook of a wideband or subband set that selects the codeword.

In the uplink system, the broadband is a bandwidth scheduled by the terminal device, and may also be an uplink full bandwidth channel.

103. The base station determines, from the broadband differential codebook, the codeword of the at least one first subband group and the codeword of the at least one second subband group;

Each of the first sub-band groups has a corresponding codeword, and each of the second sub-band groups also has a corresponding codeword.

The method for determining the first sub-band group in the broadband, as described above, may be to pre-define the identifier of the first sub-band group, or by downlink signaling, such as a Radio Resource Control (RRC) message. The ID, the MAC-ce or the Downlink Control Information (DCI) carries the identifier of the first sub-band group, and the identifier of the first sub-band group is reported after the channel is measured by the terminal device. For details, refer to the foregoing embodiment. The content described is not detailed here.

104. The base station determines a differential PMI corresponding to the codeword of the at least one first subband group in the differential codebook, and a differential PMI corresponding to the codeword of the at least one second subband group in the differential codebook.

105. The base station sends, to the terminal device, the received differential PMI of the at least one first subband group and the differential PMI of the at least one second subband group.

106. The terminal device determines, according to the received differential PMI of the at least one first subband group and the differential PMI of the at least one second subband group, the codeword of the at least one first subband group and the at least one second subband group. numbers.

In this embodiment of the present application, the base station also needs to send an absolute PMI corresponding to the broadband codeword. Thus, the terminal device determines the codeword of the at least one first subband group and the codeword of the at least one second subband group, including:

The terminal device determines the codeword of the broadband from the reference codebook according to the absolute PMI of the broadband;

The terminal device determines a differential codebook corresponding to the codeword of the broadband;

The terminal device determines, according to the received differential PMI of the at least one first subband group and the differential PMI of the at least one second subband group, the codeword and the at least one second sub of the at least one first subband group from the differential codebook. Codeword with group.

In an optional implementation manner, if the differential codebook is as shown in Table 5, that is, the differential codebook is a correspondence between the differential PMI of the codeword and the absolute PMI, the steps 103-105 may be performed in one step. That is, the base station directly determines the differential PMI of the at least one first subband group and the differential PMI of the at least one second subband group from the differential codebook corresponding to the wideband codeword. Correspondingly, in step 106, the terminal device determines, according to the received differential PMI of the at least one first subband group and the differential PMI of the at least one second subband group, a codeword and at least one of the at least one first subband group. The codeword of the second subband group includes: the differential device according to the received differential PMI of the at least one first subband group and the differential PMI of the at least one second subband group, respectively, from the differential codebook corresponding to the wideband codeword and Determining, in the differential codebook corresponding to the codeword of the adjacent subband group of the second subband group, determining an absolute PMI of the at least one first subband group and an absolute PMI of the at least one second subband group; and then, according to at least one The absolute PMI of a subband group and the absolute PMI of the at least one second subband group determine at least one codeword of the first subband group and the codeword of the at least one second subband group from the reference codebook.

In an optional implementation manner, when the base station or the terminal device determines the differential codebook corresponding to the codeword of the broadband, the optional codebook may not be used to calculate the differential codebook, but directly through the table lookup manner. The differential codebook corresponding to the codeword of the broadband is obtained, that is, the base station and the terminal device can specify a differential codebook corresponding to each codeword in the reference codebook by using a protocol, thereby saving processing resources of the base station and the terminal device.

It can be seen that the implementation shown in FIG. 2 is such that each subband group has a corresponding absolute PMI or a differential PMI, and the precoding matrix used in the subbands in the same subband group is the same, and the preamble between each subband group is used. The coding matrix can be different, so that the anti-interference ability between each sub-band group can be improved, and the spectrum efficiency and system performance of the system are greatly improved.

Referring to FIG. 4, FIG. 4 is a schematic flowchart of another method for indicating a precoding matrix according to an embodiment of the present disclosure. In the method for indicating a precoding matrix shown in FIG. 4, a codeword of a first subband group is The codeword of the second subband group is recursively derived from the first subband group as determined in the wideband differential codebook. Specifically, as shown in FIG. 4, the precoding matrix indication method may include the following steps:

201. The base station determines a broadband codeword from the reference codebook according to the measured broadband channel information.

202. The base station determines a differential codebook corresponding to the codeword of the broadband;

203. For each first subband group, the base station determines a codeword of the first subband group from the differential codebook.

204. For each second subband group, the base station determines a codeword of the second subband group from a differential codebook corresponding to a codeword of the subband group adjacent to the second subband group.

205. The base station determines, according to the codeword of each first subband group and the codeword of each second subband group, a differential PMI of each first subband group and a differential PMI of each second subband group.

206. The base station sends a differential PMI of the at least one first subband group and a differential PMI of the at least one second subband group.

207. The terminal device determines, according to the received differential PMI of the at least one first subband group and the differential PMI of the at least one second subband group, a codeword of the at least one first subband group and a codeword of the at least one second subband group. .

In an optional implementation manner, if the broadband includes a first sub-band group, in step 204, the base station determines the codeword of the second sub-band group and the differential PMI of the codeword:

1) for a second subband group in the broadband that identifies an identifier smaller than the first subband group, the codeword of the second subband group and the differential PMI of the codeword are adjacent to the second subband group and Determined in the differential codebook of the subband group that is larger than the identity of the second subband group. Taking FIG. 1b as an example, the codeword and the differential PMI of the first subband group m are determined from the wideband differential codebook; the codeword and the differential PMI of the second subband group m-1 are from the first subband. The differential codebook of group m is determined; the codeword and differential PMI of the second subband group m-2 are determined from the differential codebook of the second subband group m-1.

2) for a second subband group in the broadband that identifies an identifier greater than the first subband group, the codeword of the second subband group and the differential PMI of the codeword are from adjacent to the second subband group And determined in the differential codebook of the subband group smaller than the identifier of the second subband group. Taking FIG. 1b as an example, the codeword of the second subband group m+2 and the differential PMI of the codeword are determined from the differential codebook of the adjacent first subband group m; the second subband group m The +3 codeword and the differential PMI of the codeword are determined from the differential codebook of the adjacent second subband group m+2; the codeword of the second subband group m+4 and the difference of the codeword The PMI is determined from the differential codebook of the adjacent second subband group m+3.

In another optional implementation manner, if the broadband includes two first subband groups, the identifiers of the two first subband groups are x, y, and x < y, then in step 204, the base station determines When the codeword of the second subband group and the differential PMI of the codeword:

1) For a second subband group whose identifier is less than x in the broadband, the codeword of the second subband group and the differential PMI of the codeword are determined from a differential codebook of adjacent subband groups larger than the self identification. Taking FIG. 1a as an example, x=m, the codeword and differential PMI of the second sub-band group m-1 are determined from the differential codebook of the adjacent first sub-band group m; the second sub-band group The codeword and differential PMI of m-2 are determined from the differential codebook of the adjacent second subband group m-1;

2) For the second subband group whose identity is greater than y in the broadband, the codeword of the second subband group and the differential PMI of the codeword are determined from the differential codebook of the adjacent subband group smaller than the self identification. Taking FIG. 1a as an example, y=m+3, the codeword and differential PMI of the second sub-band group m+4 are determined from the differential codebook of the adjacent first sub-band group m+3;

3) For a second subband group whose identifier is greater than x and less than y, the codeword of the second subband group and the differential PMI of the codeword are corresponding to codewords of adjacent subband groups larger than the self identification Determined in the differential codebook; taking FIG. 1a as an example, x=m, y=m+3, the codeword and the differential codebook of the second subband group m+2 are from the adjacent first subband group m+ The differential codebook of 3 is determined; the codeword and the differential codebook of the second subband group m+1 are determined from the differential codebook of the adjacent first subband group m+2.

Optionally, in 3), for the second subband group whose identifier is greater than x and less than y, the codeword of the second subband group and the differential PMI of the codeword are adjacent subband groups smaller than the self identifier. The codeword corresponds to the difference codebook; as shown in FIG. 1a, x=m, y=m+3, and the codeword and the differential codebook of the second subband group m+1 are from the adjacent first The differential codebook of the subband group m is determined; the codeword and the differential codebook of the second subband group m+2 are determined from the differential codebook of the adjacent first subband group m+1.

Optionally, in the case of the second sub-band group whose identifier is greater than x and less than y, in the case that the identifier of the second sub-band group is greater than x but less than (yx)/2, the second sub-band group The differential PMI of the codeword and the codeword is determined from a differential codebook corresponding to a codeword of a subband group that is smaller than the self identification; the identifier of the second subband group is greater than (yx)/2 and less than In the case of y, the codeword of the second subband group and the differential PMI of the codeword are determined from a differential codebook corresponding to a codeword of a subband group that is larger than the self identification. That is, for the second sub-band group that identifies the identifiers between the two first sub-band groups, whether the first sub-band group with the smaller identifier is used as the recursion, or the first one with the larger identifier The subband group is the initial recursion and can be determined by signaling, advance agreement, or as specified by the protocol.

Correspondingly, in 207, determining, by the terminal device, the codeword of the at least one first subband group according to the received differential PMI of the at least one first subband group may include: the terminal device according to the differential PMI of the at least one first subband group from the broadband Determining at least one codeword of the first subband group in the differential codebook; for each second subband group, the terminal device is from the neighboring cell adjacent to the second subband group according to the differential PMI of the second subband group The codeword of the second subband group is determined in the differential codebook of the band. When the terminal device determines the codeword of the second subband group, it is still obtained from the first subband group as a starting recursion, and may specifically refer to the difference PMI of the received second subband group in the above example. , 2), or 1), 2), 3), the codeword is determined from the corresponding differential codebook.

In another embodiment, the difference from the embodiment shown in FIG. 4 is that the codewords of the first subband group are selected from the reference codebook, that is, the PMI of the first subband group is an absolute PMI. The codeword of the second sub-band group is still selected from the first sub-band group as the above-mentioned optional implementation manner. Correspondingly, the PMI of the second sub-band group is a differential PMI.

Therefore, the precoding matrix indication method used by the base station and the terminal device may include at least the foregoing three embodiments. Therefore, the base station needs to send indication information to the terminal device, and the terminal device may determine, according to the indication information, which implementation manner is used to obtain The codeword corresponding to each subband group. The indication information may be sent by means of signaling, such as RRC, MAC-ce or DCI. The indication information may be identified by 2 bits, such as 00 for the embodiment shown in FIG. 3; 01 for the embodiment shown in FIG. 4; and 10 for the first sub-band group similar to FIG. 4 described above. The PMI is an embodiment of an absolute PMI.

In summary, in the uplink system, the terminal device can obtain the codewords of each sub-band group separately, thereby considering the frequency selectivity of the channel, which is beneficial to improving system performance. In addition, the differential PMI is used in the precoding matrix indication information sent by the base station to indicate the codeword, which can greatly reduce the signaling overhead.

In the downlink system, the base station may send the indication information, the protocol agreement, or the signaling manner to the terminal device, so that the terminal device learns the precoding matrix indication method according to any one of the foregoing three embodiments, and thus, the terminal The device may feed back the PMI to the base station in a corresponding manner. Optionally, the terminal device may determine, by using its own measurement result, which precoding matrix indication method is used to feed back the PMI. In addition, in the downlink system, the broadband may be a broadband obtained by the terminal device through channel measurement, and the codeword of the broadband may be selected from the reference codebook according to channel information at a certain time or a preset duration. In the downlink system, the terminal device can perform the related operations of the base station in the uplink system, and the base station in the downlink system can perform the related operations of the terminal device in the uplink system. Therefore, for the precoding matrix indication method in the downlink system, reference may be made to the related content. It will not be detailed here.

Referring to FIG. 5, FIG. 5 is a schematic structural diagram of a device according to an embodiment of the present disclosure. As shown in FIG. 5, the device may include a processing unit 301 and a communication unit 302, where:

The processing unit 301 is configured to determine a precoding matrix indication of at least one first subband group in the broadband and a precoding matrix indication of the at least one second subband group in the broadband;

The precoding matrix indication of the first subband group is an absolute precoding matrix indication determined based on a reference codebook, or a differential precoding matrix indication determined based on a differential codebook;

The precoding matrix indication of the second subband group is a differential precoding matrix indication determined based on the differential codebook;

The differential codebook is mapped from the reference codebook;

The communication unit 302 is configured to send a precoding matrix indication of the at least one first subband group and a precoding matrix indication of the at least one second subband group.

In an optional implementation manner, when the precoding matrix indication of the first subband group is an absolute precoding matrix indication determined based on a reference codebook, the processing unit 301 is specifically configured to use the reference code. Selecting a codeword of the first subband group; and determining an absolute precoding matrix indication of the first subband group based on the codeword of the first subband group.

In an optional implementation manner, when the precoding matrix indication of the first subband group is indicated by a differential precoding matrix determined by the differential codebook, the processing unit 301 is specifically configured to use the differential codebook. Selecting a codeword of the first subband group; and determining a differential precoding matrix indication of the first subband group according to the codeword of the first subband group;

The differential codebook is obtained by mapping the wideband codeword, and the wideband codeword is selected by the transmitting end from the reference codebook according to the measured broadband channel information.

In an optional implementation manner, the precoding matrix indication of the second subband group is a differential precoding matrix indication determined based on a differential codebook, where the processing unit 301 is specifically configured to determine a differential codebook. The differential codebook is obtained by mapping a codeword corresponding to the subband group adjacent to the second subband group; selecting a codeword of the second subband group from the differential codebook, and according to the The codewords of the two subband groups determine the differential precoding matrix indication of the second subband group.

In an optional implementation manner, the differential codebook is mapped from the reference codebook, and includes: the differential codebook includes a codeword that is a target codeword in the reference codebook. The beam coefficients are obtained by differential operation.

In an optional implementation manner, the target codeword is the codeword of the wideband or a codeword corresponding to a subband group adjacent to the second subband group.

In an optional implementation manner, the differential precoding matrix indicates a number of bits of 1-4 bits.

In an optional implementation manner, the communication unit 302 is further configured to send indication information, where the indication information is used to indicate that the precoding matrix indication information sent by the communication unit 302 includes a differential precoding matrix indication.

The units shown in FIG. 5 can perform the related operations of the transmitting end in the foregoing embodiments in combination with the various embodiments described above.

In another optional implementation manner, each unit shown in FIG. 5 can also perform related operations of the receiving end in the foregoing embodiment, for example:

The communication unit 302 is configured to receive a precoding matrix indication of the at least one first subband group and a precoding matrix indication of the at least one second subband group;

The processing unit 301 is configured to determine, according to the precoding matrix of the at least one first subband group, a codeword of the at least one first subband group from a reference codebook or a differential codebook; and according to the at least one The precoding matrix of the second subband group indicates that the codeword of the at least one second subband group is determined from the differential codebook;

The differential codebook is mapped from the reference codebook.

The processing unit 301 is further configured to determine a broadband codeword from the reference codebook, where the broadband includes the at least one first subband group and the at least one second subband group; and determine the A differential codebook mapped by a wideband codeword, the differential codebook being used as a differential codebook used to determine a codeword of the at least one first subband group.

For each of the at least one second sub-band group, the processing unit 301 is further configured to acquire a codeword of the sub-band group adjacent to the second sub-band group; and determine The differential codebook to which the codewords of the adjacent subband groups are mapped, and the differential codebook is used as a differential codebook used to determine the codewords of the second subband group.

For the foregoing embodiment or the embodiment, related content that can be executed by both the receiving end and the transmitting end may also be performed by the determining unit 301 and the communication unit 302, and details are not described herein.

FIG. 6 is a schematic diagram of another device according to an embodiment of the present disclosure. As shown in FIG. 6 , the device may be a terminal device 10 , or may be a chip or a circuit, such as a chip that can be disposed on a terminal device or Circuit. The terminal device 10 may correspond to related operations of the transmitting end in the foregoing method, and may also perform related operations of the receiving end.

The device can include a processor 110 and a memory 120. The memory 120 is for storing instructions for executing the instructions stored by the memory 120 to implement the steps performed by the base station or terminal device as described above.

Further, the device may further include a receiver 140 and a transmitter 150. Further, the device may further include a bus system 130, wherein the processor 110, the memory 120, the receiver 140, and the transmitter 150 may be connected by the bus system 130.

The processor 110 is configured to execute instructions stored by the memory 120 to control the receiver 140 to receive signals and control the transmitter 150 to transmit signals to complete the steps of the terminal device in the above method. The receiver 140 and the transmitter 150 may be the same or different physical entities. When they are the same physical entity, they can be collectively referred to as transceivers. The memory 220 may be integrated in the processor 210 or may be provided separately from the processor 210.

As an implementation, the functions of the receiver 140 and the transmitter 150 can be implemented by a dedicated chip through a transceiver circuit or a transceiver. The processor 110 can be implemented by a dedicated processing chip, a processing circuit, a processor, or a general purpose chip.

As another implementation manner, the terminal device provided by the embodiment of the present application may be implemented by using a general-purpose computer. The program code that is to implement the functions of the processor 110, the receiver 140 and the transmitter 150 is stored in a memory, and the general purpose processor implements the functions of the processor 110, the receiver 140 and the transmitter 150 by executing the code in the memory.

For the concepts, explanations, detailed descriptions and other steps related to the technical solutions provided by the embodiments of the present application, refer to the descriptions of the foregoing methods or other embodiments, and no further details are provided herein.

FIG. 7 is a schematic structural diagram of a terminal device according to an embodiment of the present disclosure. This device can be adapted for use in the system shown in FIG. 2. For convenience of explanation, FIG. 7 shows only the main components of the terminal device. As shown in FIG. 7, the terminal device 10 includes a processor, a memory, a control circuit, an antenna, and an input and output device. The processor is mainly used for processing the communication protocol and the communication data, and controlling the entire terminal device, executing the software program, and processing the data of the software program, for example, in the embodiment of the indication method for supporting the terminal device to perform the foregoing transmission precoding matrix. The action described. The memory is primarily used to store software programs and data, such as the reference codebook or differential codebook described in the above embodiments. The control circuit is mainly used for converting baseband signals and radio frequency signals and processing radio frequency signals. The control circuit together with the antenna can also be called a transceiver, and is mainly used for transmitting and receiving RF signals in the form of electromagnetic waves. Input and output devices, such as touch screens, display screens, keyboards, etc., are primarily used to receive user input data and output data to the user.

After the terminal device is powered on, the processor can read the software program in the storage unit, interpret and execute the instructions of the software program, and process the data of the software program. When the data needs to be transmitted by wireless, the processor performs baseband processing on the data to be sent, and then outputs the baseband signal to the radio frequency circuit. The radio frequency circuit performs radio frequency processing on the baseband signal, and then sends the radio frequency signal to the outside through the antenna in the form of electromagnetic waves. When data is transmitted to the terminal device, the RF circuit receives the RF signal through the antenna, converts the RF signal into a baseband signal, and outputs the baseband signal to the processor, which converts the baseband signal into data and processes the data.

Those skilled in the art will appreciate that FIG. 7 shows only one memory and processor for ease of illustration. In an actual terminal device, there may be multiple processors and memories. The memory may also be referred to as a storage medium or a storage device, and the like.

As an optional implementation manner, the processor may include a baseband processor and a central processing unit, and the baseband processor is mainly used to process the communication protocol and the communication data, and the central processing unit is mainly used to control and execute the entire terminal device. A software program that processes data from a software program. The processor in FIG. 7 integrates the functions of the baseband processor and the central processing unit. Those skilled in the art can understand that the baseband processor and the central processing unit can also be independent processors and interconnected by technologies such as a bus. Those skilled in the art will appreciate that the terminal device may include a plurality of baseband processors to accommodate different network standards, and the terminal device may include a plurality of central processors to enhance its processing capabilities, and various components of the terminal devices may be connected through various buses. The baseband processor can also be expressed as a baseband processing circuit or a baseband processing chip. The central processing unit can also be expressed as a central processing circuit or a central processing chip. The functions of processing the communication protocol and the communication data may be built in the processor, or may be stored in the storage unit in the form of a software program, and the processor executes the software program to implement the baseband processing function.

Illustratively, in an embodiment of the invention, an antenna and a control circuit having a transceiving function can be regarded as a communication unit or a transceiving unit of the terminal device 10, and a processor having a processing function is regarded as a determining unit or a processing unit of the terminal device 10. . As shown in FIG. 7, the terminal device 10 includes a transceiver unit 101 and a processing unit 102. The transceiver unit can also be referred to as a transceiver, a transceiver, a transceiver, and the like. Optionally, the device for implementing the receiving function in the transceiver unit 101 can be regarded as a receiving unit, and the device for implementing the sending function in the transceiver unit 101 is regarded as a sending unit, that is, the transceiver unit 101 includes a receiving unit and a sending unit. The receiving unit may also be referred to as a receiver, a receiver, a receiving circuit, etc., and the transmitting unit may be referred to as a transmitter, a transmitter, or a transmitting circuit.

According to the foregoing method, FIG. 8 is a schematic structural diagram of another device according to an embodiment of the present application. As shown in FIG. 8, the device may be a network device 20, or may be a chip or a circuit, such as a chip that can be disposed in a network device. Or circuit. The network device 20 performs the related operations of the transmitting end and/or the receiving end in the above method. The device can include a processor 210 and a memory 220. The memory 220 is configured to store instructions for executing the instructions stored by the memory 220 to cause the device to implement related operations of the aforementioned transmitting end or receiving end.

Further, the network may further include a receiver 240 and a transmitter 250. Still further, the network can also include a bus system 230.

The processor 210, the memory 220, the receiver 240 and the transmitter 250 are connected by a bus system 230, and the processor 210 is configured to execute instructions stored in the memory 220 to control the receiver 240 to receive signals and control the transmitter 250 to send signals. The steps of the network device in the above method are completed. The receiver 240 and the transmitter 250 may be the same or different physical entities. When they are the same physical entity, they can be collectively referred to as transceivers. The memory 220 may be integrated in the processor 210 or may be provided separately from the processor 210.

As an implementation, the functions of the receiver 240 and the transmitter 250 can be implemented by a dedicated chip through a transceiver circuit or a transceiver. The processor 210 can be implemented by a dedicated processing chip, a processing circuit, a processor, or a general purpose chip.

As another implementation manner, a network device provided by an embodiment of the present application may be implemented by using a general-purpose computer. The program code that is to implement the functions of the processor 210, the receiver 240 and the transmitter 250 is stored in a memory, and the general purpose processor implements the functions of the processor 210, the receiver 240, and the transmitter 250 by executing code in the memory.

According to the foregoing method, FIG. 9 is a schematic structural diagram of a network device according to an embodiment of the present application, which may be a schematic structural diagram of a base station. As shown in FIG. 9, the base station can be applied to the system as shown in FIG. 2. The base station 20 includes one or more radio frequency units, such as a remote radio unit (RRU) 201 and one or more baseband units (BBUs) (also referred to as digital units, DUs) 202. . The RRU 201 may be referred to as a transceiver unit, a transceiver, a transceiver circuit, or a transceiver, etc., which may include at least one antenna 2011 and a radio frequency unit 2012. The RRU 201 is mainly used for transmitting and receiving radio frequency signals and converting radio frequency signals and baseband signals, for example, for transmitting the signaling messages described in the foregoing embodiments to the terminal device. The BBU 202 part is mainly used for performing baseband processing, controlling a base station, and the like. The RRU 201 and the BBU 202 may be physically disposed together or physically separated, that is, distributed base stations.

The BBU 202 is a control center of a base station, and may also be referred to as a processing unit, and is mainly used to perform baseband processing functions such as channel coding, multiplexing, modulation, spread spectrum, and the like. For example, the BBU (processing unit) can be used to control the base station to perform an operation procedure about the network device in the foregoing method embodiment.

In an example, the BBU 202 may be composed of one or more boards, and multiple boards may jointly support a single access standard radio access network (such as an LTE network), or may separately support different access modes of wireless. Access Network. The BBU 202 also includes a memory 2021 and a processor 2022. The memory 2021 is used to store necessary instructions and data. For example, the memory 2021 stores preset information, a codebook, and the like in the above embodiment. The processor 2022 is configured to control the base station to perform necessary actions, for example, to control the base station to perform an operation procedure about the network device in the foregoing method embodiment. The memory 2021 and the processor 2022 can serve one or more boards. That is, the memory and processor can be individually set on each board. It is also possible that multiple boards share the same memory and processor. In addition, the necessary circuits can be set on each board.

The embodiment of the present application further provides a communication system including the foregoing network device and one or more terminal devices.

It should be understood that, in the embodiment of the present application, the processor may be a central processing unit ("CPU"), and the processor may also be other general-purpose processors, digital signal processors (DSPs), and dedicated integration. Circuit (ASIC), off-the-shelf programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, etc. The general purpose processor may be a microprocessor or the processor or any conventional processor or the like.

The memory can include read only memory and random access memory and provides instructions and data to the processor. A portion of the memory may also include a non-volatile random access memory.

The bus system may include a power bus, a control bus, and a status signal bus in addition to the data bus. However, for the sake of clarity, the various buses are labeled as bus systems in the figure.

In the implementation process, each step of the above method may be completed by an integrated logic circuit of hardware in a processor or an instruction in a form of software. The steps of the method disclosed in the embodiments of the present application may be directly implemented as a hardware processor, or may be performed by a combination of hardware and software modules in the processor. The software module can be located in a conventional storage medium such as random access memory, flash memory, read only memory, programmable read only memory or electrically erasable programmable memory, registers, and the like. The storage medium is located in the memory, and the processor reads the information in the memory and combines the hardware to complete the steps of the above method. To avoid repetition, it will not be described in detail here.

It is also to be understood that the first, second, third, fourth,

It should be understood that the term "and/or" herein is merely an association relationship describing an associated object, indicating that there may be three relationships, for example, A and/or B, which may indicate that A exists separately, and A and B exist simultaneously. There are three cases of B alone. In addition, the character "/" in this article generally indicates that the contextual object is an "or" relationship.

It should be understood that, in various embodiments of the present application, the size of the serial numbers of the above processes does not mean the order of execution, and the order of execution of each process should be determined by its function and internal logic, and should not be taken to the embodiments of the present invention. The implementation process constitutes any limitation.

Those of ordinary skill in the art will appreciate that the various illustrative logical blocks and steps described in connection with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. achieve. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods for implementing the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the present invention.

A person skilled in the art can clearly understand that for the convenience and brevity of the description, the specific working process of the system, the device and the unit described above can refer to the corresponding process in the foregoing method embodiment, and details are not described herein again.

In the several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the device embodiments described above are merely illustrative. For example, the division of the unit is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be in an electrical, mechanical or other form.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, it 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 the computer program instructions are loaded and executed on a computer, the processes or functions described in accordance with embodiments of the present invention are generated in whole or in part. The computer can be a general purpose computer, a special purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer readable storage medium or transferred from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions can be from a website site, computer, server or data center Transfer to another website site, computer, server, or data center by wire (eg, coaxial cable, fiber optic, digital subscriber line (DSL), or wireless (eg, infrared, wireless, microwave, etc.). The computer readable storage medium can be any available media that can be accessed by a computer or a data storage device such as a server, data center, or the like that includes one or more available media. The usable medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a DVD), or a semiconductor medium (such as a solid state disk (SSD)).

The above is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope of the present invention. It should be covered by the scope of the present invention. Therefore, the scope of the invention should be determined by the scope of the appended claims.

Claims

A precoding matrix indication method, comprising:

Transmitting, by the transmitting end, a precoding matrix indication of at least one first subband group in the broadband and a precoding matrix indication of at least one second subband group in the broadband;

The precoding matrix indication of the first subband group is an absolute precoding matrix indication determined based on a reference codebook, or a differential precoding matrix indication determined based on a differential codebook;

The precoding matrix indication of the second subband group is a differential precoding matrix indication determined based on the differential codebook;

The differential codebook is mapped from the reference codebook;

And transmitting, by the transmitting end, a precoding matrix indication of the at least one first subband group and a precoding matrix indication of the at least one second subband group.
The precoding matrix indication method according to claim 1, wherein the precoding matrix indication of the first subband group is an absolute precoding matrix indication determined based on a reference codebook, and includes:

The transmitting end selects a codeword of the first subband group from the reference codebook;

The transmitting end determines an absolute precoding matrix indication of the first subband group based on a codeword of the first subband group.
The precoding matrix indication method according to claim 1, wherein the precoding matrix indication of the first subband group is a differential precoding matrix indication determined based on a differential codebook, comprising:

The transmitting end selects a codeword of the first subband group from a differential codebook;

Determining, by the transmitting end, a differential precoding matrix indication of the first subband group according to a codeword of the first subband group;

The differential codebook is obtained by mapping the wideband codeword, and the wideband codeword is selected by the transmitting end from the reference codebook according to the measured broadband channel information.
The precoding matrix indication method according to claim 1, wherein the precoding matrix indication of the first subband group is a differential precoding matrix indication determined based on a differential codebook, comprising:

Determining, by the transmitting end, a differential precoding matrix indication of the first subband group from a differential codebook, where the differential codebook is obtained by mapping the wideband codeword, where the broadband codeword is The transmitting end selects from the reference codebook according to the measured broadband channel information.
The precoding matrix indication method according to any one of claims 1 to 4, wherein the precoding matrix indication of the second subband group is a differential precoding matrix indication determined based on the differential codebook, and includes:

The transmitting end determines a differential codebook, where the differential codebook is obtained by mapping a codeword corresponding to the subband group adjacent to the second subband group;

The transmitting end selects a codeword of the second subband group from the differential codebook, and determines a differential precoding matrix indication of the second subband group according to the codeword of the second subband group.
The precoding matrix indication method according to any one of claims 1 to 4, wherein the precoding matrix indication of the second subband group is a differential precoding matrix indication determined based on the differential codebook, and includes:

Determining, by the transmitting end, a differential precoding matrix indication of the second subband group from a differential codebook, where the differential codebook is a codeword mapping corresponding to a subband group adjacent to the second subband group owned.
The precoding matrix indication method according to any one of claims 1 to 4, wherein the first subband group is predefined, or is notified by downlink signaling, or is measured by a channel. The uplink signaling is reported.
The precoding matrix indication method according to claim 1, wherein the differential codebook is mapped from the reference codebook, and the method includes: the differential codebook includes a codeword from the reference The codebook that is selected in the codeword that satisfies the preset rule.
The precoding matrix indication method according to claim 8, wherein the codeword that satisfies the preset rule is a codeword whose distance from the target codeword is within a preset distance, or is related to the target codeword. The correlation between the codewords that meet the preset conditions.
The precoding matrix indication method according to claim 1, wherein the differential codebook is mapped from the reference codebook, and the codeword included in the differential codebook is for the reference The beam coefficients of the target codeword in the codebook are obtained by differential operation.
The precoding matrix indication method according to claim 9 or 10, wherein the target codeword is the wideband codeword or a codeword of a subband group adjacent to the second subband group .
The precoding matrix indication method according to any one of claims 1 to 9, wherein the differential precoding matrix of each codeword included in the differential codebook indicates the codewords after being arranged in ascending or descending order The absolute precoding matrix indicates the corresponding.
The precoding matrix indication method according to any one of claims 1 to 12, wherein the number of bits indicated by the differential precoding matrix is 1-4 bits.
The precoding matrix indication method according to any one of claims 1 to 11, wherein the method further comprises:

The transmitting end sends indication information, where the indication information is used to indicate that the precoding matrix indication information sent by the transmitting end includes a differential precoding matrix indication.
A precoding matrix indication method, comprising:

Receiving, by the receiving end, a precoding matrix indication of the at least one first subband group and a precoding matrix indication of the at least one second subband group;

Determining, by the receiving end, the codeword of the at least one first subband group from the reference codebook according to an absolute precoding matrix of the at least one first subband group, or according to the at least one first subband group a differential precoding matrix indicating determining a codeword of the at least one first subband group from the differential codebook; and determining the from the differential codebook according to the differential precoding matrix indication of the at least one second subband group a codeword of at least one second subband group;

The differential codebook is mapped from the reference codebook.
The precoding matrix indication method according to claim 15, wherein the method further comprises:

The receiving end determines a wideband codeword from the reference codebook, the broadband comprising the at least one first subband group and the at least one second subband group;

The receiving end determines a differential codebook mapped by the wideband codeword, and uses the differential codebook as a differential codebook used to determine a codeword of the at least one first subband group.
The method of claim 15 wherein the method further comprises:

And for each second subband group of the at least one second subband group, the receiving end acquires a codeword of a subband group adjacent to the second subband group;

The receiving end determines a differential codebook mapped by a codeword of the adjacent subband group, and uses the differential codebook as a differential codebook used to determine a codeword of the second subband group.
An apparatus, comprising:

a processing unit, configured to determine a precoding matrix indication of at least one first subband group in the broadband and a precoding matrix indication of at least one second subband group in the broadband;

The precoding matrix indication of the first subband group is an absolute precoding matrix indication determined based on a reference codebook, or a differential precoding matrix indication determined based on a differential codebook;

The precoding matrix indication of the second subband group is a differential precoding matrix indication determined based on the differential codebook;

The differential codebook is mapped from the reference codebook;

And a communication unit, configured to send a precoding matrix indication of the at least one first subband group and a precoding matrix indication of the at least one second subband group.
The device according to claim 18, wherein the processing unit is configured to: when the precoding matrix indication of the first subband group is an absolute precoding matrix indication determined based on a reference codebook, Selecting a codeword of the first subband group in the reference codebook; and determining an absolute precoding matrix indication of the first subband group based on the codeword of the first subband group.
The device according to claim 18, wherein the processing unit is configured to: when the precoding matrix indication of the first subband group is based on a differential precoding matrix indication determined by a differential codebook, Selecting a codeword of the first subband group in the codebook; and determining a differential precoding matrix indication of the first subband group according to the codeword of the first subband group;

The differential codebook is obtained by mapping the wideband codeword, and the wideband codeword is selected by the transmitting end from the reference codebook according to the measured broadband channel information.
The device according to claim 18, wherein the processing unit is configured to: when the precoding matrix indication of the first subband group is based on a differential precoding matrix indication determined by a differential codebook, Determining, in the codebook, a differential precoding matrix indication of the first subband group;

The differential codebook is obtained by mapping the wideband codeword, and the wideband codeword is selected by the transmitting end from the reference codebook according to the measured broadband channel information.
The device according to any one of claims 18 to 21, wherein the processing unit is configured to: in the second subband group, the precoding matrix indication is a differential precoding matrix determined based on the differential codebook. Determining, determining a differential codebook obtained by mapping a codeword corresponding to a subband group adjacent to the second subband group; selecting the second subband group from the differential codebook a codeword, and determining a differential precoding matrix indication of the second subband group based on the codeword of the second subband group.
The device according to any one of claims 18 to 21, wherein the processing unit is configured to: in the second subband group, the precoding matrix indication is a differential precoding matrix determined based on the differential codebook. Determining, determining, by the differential codebook, a differential precoding matrix indication of the second subband group;

The differential codebook is obtained by mapping a codeword corresponding to a subband group adjacent to the second subband group.
The device according to any one of claims 18 to 21, wherein the first sub-band group is predefined, or is notified by downlink signaling, or is reported by uplink signaling after channel measurement. of.
The device according to claim 18, wherein the differential codebook is mapped from the reference codebook, comprising: the differential codebook includes a codeword that is satisfied from the reference codebook The codeword selected in the preset rule.
The device according to claim 25, wherein the codeword satisfying the preset rule is a codeword whose distance from the target codeword is within a preset distance, or a correlation with the target codeword A codeword that meets the preset conditions.
The device according to claim 18, wherein the differential codebook is mapped from the reference codebook, comprising: the differential codebook includes a codeword that is a target in the reference codebook The beam coefficient of the codeword is obtained by differential operation.
The apparatus according to claim 26 or 27, wherein said target codeword is said wideband codeword or a codeword of a subband group adjacent to said second subband group.
The device according to any one of claims 18 to 28, wherein the differential precoding matrix of each codeword included in the differential codebook indicates absolute precoding of the codewords after ascending or descending ordering The matrix indicates the corresponding.
The apparatus according to any one of claims 18 to 29, wherein the number of bits indicated by the differential precoding matrix is 1-4 bits.
Apparatus according to any one of claims 18 to 28, wherein

The communication unit is further configured to send indication information, where the indication information is used to indicate that the precoding matrix indication information includes a differential precoding matrix indication.
An apparatus, comprising:

a communication unit, configured to receive a precoding matrix indication of the at least one first subband group and a precoding matrix indication of the at least one second subband group;

a processing unit, configured to determine, according to a precoding matrix of the at least one first subband group, a codeword of the at least one first subband group from a reference codebook or a differential codebook; and according to the at least one The precoding matrix of the two subband groups indicates that the codewords of the at least one second subband group are determined from the differential codebook;

The precoding matrix indication of the first subband group is an absolute precoding matrix indication determined based on a reference codebook, or a differential precoding matrix indication determined based on a differential codebook;

The precoding matrix indication of the second subband group is a differential precoding matrix indication determined based on the differential codebook;

The differential codebook is mapped from the reference codebook.
The device of claim 32, wherein

The processing unit is further configured to determine a wideband codeword from the reference codebook, the broadband includes the at least one first subband group and the at least one second subband group; and determine the broadband The differential codebook mapped by the codeword is used as the differential codebook used to determine the codeword of the at least one first subband group.
The device according to claim 32, wherein the processing unit is further configured to acquire the second sub-band group for each of the at least one second sub-band group a codeword of the adjacent subband group; and a differential codebook mapped by the codeword of the adjacent subband group, the differential codebook being used as a codeword for determining the second subband group Differential codebook.
An apparatus, comprising: a processor and a transceiver;

The processor, configured to determine a precoding matrix indication of at least one first subband group in the broadband and a precoding matrix indication of at least one second subband group in the broadband;

The precoding matrix indication of the first subband group is an absolute precoding matrix indication determined based on a reference codebook, or a differential precoding matrix indication determined based on a differential codebook;

The precoding matrix indication of the second subband group is a differential precoding matrix indication determined based on the differential codebook;

The differential codebook is mapped from the reference codebook;

The transceiver is configured to send a precoding matrix indication of the at least one first subband group and a precoding matrix indication of the at least one second subband group.
The device according to claim 35, wherein said processor is configured to: when said precoding matrix indication of said first subband group is based on an absolute precoding matrix indication determined by a reference codebook Selecting a codeword of the first subband group in a reference codebook; and determining an absolute precoding matrix indication of the first subband group based on a codeword of the first subband group.
The device according to claim 35, wherein the processor is configured to: when the precoding matrix indication of the first subband group is based on a differential precoding matrix indication determined by a differential codebook, Selecting a codeword of the first subband group; and determining, by the codeword of the first subband group, a differential precoding matrix indication of the first subband group;

The differential codebook is obtained by mapping the wideband codeword, and the wideband codeword is selected by the transmitting end from the reference codebook according to the measured broadband channel information.
The device according to claim 35, wherein the processor is configured to: when the precoding matrix indication of the first subband group is based on a differential precoding matrix indication determined by a differential codebook, Determining, in the present, a differential precoding matrix indication of the first subband group;

The differential codebook is obtained by mapping the wideband codeword, and the wideband codeword is selected by the transmitting end from the reference codebook according to the measured broadband channel information.
The device according to any one of claims 35 to 38, wherein the processor, the precoding matrix indication at the second subband group is a differential precoding matrix indication determined based on a differential codebook Determining a differential codebook obtained by mapping a codeword corresponding to a subband group adjacent to the second subband group; and for selecting the second subtitle from the differential codebook And a codeword of the group, and determining a differential precoding matrix indication of the second subband group according to the codeword of the second subband group.
The device according to any one of claims 35 to 38, wherein the processor, the precoding matrix indication at the second subband group is a differential precoding matrix indication determined based on a differential codebook Determining, by the differential codebook, a differential precoding matrix indication of the second subband group;

The differential codebook is obtained by mapping a codeword corresponding to a subband group adjacent to the second subband group.
The device according to any one of claims 35 to 38, wherein the first sub-band group is predefined, or is notified by downlink signaling, or is reported by uplink signaling after channel measurement. of.
The device according to claim 35, wherein said differential codebook is mapped from said reference codebook, comprising: said differential codebook comprises a codeword that is satisfied from said reference codebook The codeword selected in the preset rule.
The device according to claim 42, wherein the codeword satisfying the preset rule is a codeword whose distance from the target codeword is within a preset distance, or a correlation with the target codeword A codeword that meets the preset conditions.
The device according to claim 35, wherein the differential codebook is mapped from the reference codebook, comprising: the differential codebook includes a codeword that is a target in the reference codebook The beam coefficient of the codeword is obtained by differential operation.
The apparatus according to claim 43 or 44, wherein said target codeword is said wideband codeword or a codeword of a subband group adjacent to said second subband group.
The device according to any one of claims 35 to 45, wherein the differential precoding matrix of each codeword included in the differential codebook indicates absolute precoding of the codewords after ascending or descending ordering The matrix indicates the corresponding.
The apparatus according to any one of claims 35 to 46, wherein the number of bits indicated by the differential precoding matrix is 1-4 bits.
Apparatus according to any one of claims 35 to 45, wherein

The transceiver is further configured to send indication information, where the indication information is used to indicate that the precoding matrix indication information includes a differential precoding matrix indication.
An apparatus, comprising: a transceiver and a processor;

The transceiver is configured to receive a precoding matrix indication of at least one first subband group and a precoding matrix indication of at least one second subband group;

The processor, configured to determine, according to a precoding matrix of the at least one first subband group, a codeword of the at least one first subband group from a reference codebook or a differential codebook; and according to the at least a precoding matrix of a second subband group indicating determining a codeword of the at least one second subband group from the differential codebook;

The precoding matrix indication of the first subband group is an absolute precoding matrix indication determined based on a reference codebook, or a differential precoding matrix indication determined based on a differential codebook;

The precoding matrix indication of the second subband group is a differential precoding matrix indication determined based on the differential codebook;

The differential codebook is mapped from the reference codebook.
The device of claim 49, wherein

The processor is further configured to determine a wideband codeword from the reference codebook, the broadband comprising the at least one first subband group and the at least one second subband group; and The differential codebook mapped by the wideband codeword is used as the differential codebook used to determine the codeword of the at least one first subband group.
The device according to claim 49, wherein the processor is further configured to acquire the second sub-band group for each of the at least one second sub-band group a codeword of an adjacent subband group; and a differential codebook for determining a codeword of the adjacent subband group, the differential codebook being used as a codeword for determining the second subband group The differential codebook used.
A chip system, comprising: a processor and an interface;

The processor is for implementing the method of any one of claims 1 to 14.
The chip system of claim 52 wherein said chip system further comprises a memory for storing program instructions.
A chip system, comprising: a processor and an interface;

The processor is for implementing the method of any one of claims 15 to 17.
The chip system of claim 54 wherein said chip system further comprises a memory for storing program instructions.
A computer storage medium for storing a computer program, when the computer program is run on a computer, causing the computer to perform the method of any one of claims 1 to 14, or The method of any one of claims 15 to 17.
A computer program product, characterized in that when the computer program product is run on a computer, the computer is caused to perform the method of any one of claims 1 to 14, or to perform any of claims 15 to 17 One of the methods described.
A communication system, characterized in that the communication system comprises:

The apparatus according to any one of claims 35 to 48 and the apparatus according to any one of claims 49 to 51; or

Apparatus according to any of claims 18-31 and apparatus according to any of claims 32-34.