# US 10,374,673 B2 · Information feedback method, user equipment, and network device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,374,673 B2 - Document ID: US10374673B2 - Status: Granted - Kind: B2 - Application number: 16/228,357 - Filed: 2018-12-20 - Published: 2019-04-25 - Granted: 2019-08-06 - Earliest claimed: 2016-11-04 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co.,Ltd. - Inventors: Huangping Jin; Wei Han; Peng Shang; Xiaoyan Bi - Web page: https://patentgrep.com/patent/US10374673B2 ## CPC - H04B 7/0626: {Channel coefficients, e.g. channel state information [CSI]} - H04B 7/0417: Feedback systems - H04B 7/063: {Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection} - H04B 7/0639: {Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection} - H04B 7/0658: {Feedback reduction} - H04B: TRANSMISSION ## Abstract The present invention belongs to the field of communications technologies, and discloses a channel state information CSI feedback method and an apparatus. The method includes: determining a codebook of at each transport layer CSI of user equipment UE, where the codebook of the CSI at each transport layer of the UE is: W=W1×W2 an element Xi in W2 is a weighting coefficient corresponding to each codeword in W1, and i is an integer greater than or equal to 1 and less than or equal to K; determining a quantity Ni of bits occupied by a quantized value of an ith element in W2, where quantized values of at least two elements in W2 occupy different quantities of bits; and feeding back the quantized value of the ith element to a network device based on Ni. ## Claims ### Claim 1 A channel state information (CSI) feedback method, comprising: determining, by a user equipment, a codebook of CSI at each transport layer of user equipment (UE), wherein the codebook of the CSI at each transport layer of the UE is: W=W1×W2, wherein W is the codebook of the CSI at each transport layer of the UE, W1 is a level-1 codebook, W1=[b1 b2 . . . bK], bi in W1 represents a codeword, K is a quantity of columns of W1, K is a positive integer greater than or equal to 1, W2 is a level-2 codebook, W2 is represented as W2=[X1 X2 . . . XK]T, an element Xi in W2 is a weighting coefficient corresponding to bi in W1, and i is an integer greater than or equal to 1 and less than or equal to K; determining, by a user equipment, a quantity Ni of bits occupied by a quantized value of an ith element in W2, wherein quantized values of at least two elements in W2 occupy different quantities of bits; and feeding back, by a user equipment, the quantized value of the ith element to a network device based on Ni. ### Claim 2 (depends on 1) The method according to claim 1, further comprising: performing normalization processing on W2 based on an Nth element in W2, wherein N is an integer greater than or equal to 1 and less than or equal to K; and the determining a quantity Ni of bits occupied by a quantized value of an ith element in W2 comprises: when i=N, determining that Ni=0. ### Claim 3 (depends on 2) The method according to claim 2, wherein the determining a quantity Ni of bits occupied by a quantized value of an ith element in W2 comprises: when i≠N, a value of Ni is positively correlated to an amplitude value of the ith element. ### Claim 4 (depends on 2) The method according to claim 2, wherein a value of N is a value pre-agreed on between the UE and the network device. ### Claim 5 (depends on 2) The method according to claim 2, wherein when i≠N, Ni=Nbase+Nadd,i, wherein Nbase is a base quantity of bits occupied by the quantized value of the ith element, and Nadd,i is a additional quantity of bits occupied by the quantized value of the ith element. ### Claim 6 A user equipment (UE), comprising: a processor configured to determine a codebook of CSI of the UE at each transport layer, wherein the codebook of the CSI at each transport layer of the UE is: W=W1×W2, wherein W is the codebook of the CSI at each transport layer of the UE, W1 is a level-1 codebook, W1=[b1 b2 . . . bK], bi in W1 represents a codeword, K is a quantity of columns of W1 and K is a positive integer greater than or equal to 1, W2 is a level-2 codebook, W2 is represented as W2=[X1 X2 . . . XK]T, an element Xi in W2 is a weighting coefficient corresponding to bi in W1, and i is an integer greater than or equal to 1 and less than or equal to K; the processor is further configured to determine a quantity Ni of bits occupied by a quantized value of an ith element in W2, wherein quantized values of at least two elements in W2 occupy different quantities of bits; and a transmitter, configured to feed back the quantized value of the ith element to a network device based on Ni. ### Claim 7 (depends on 6) The user equipment according to claim 6, wherein the processor is further configured to perform normalization processing on W2 based on an Nth element in W2, wherein N is an integer greater than or equal to 1 and less than or equal to K; and when i=N, Ni=0. ### Claim 8 (depends on 7) The user equipment according to claim 7, wherein when i≠N, a value of Ni is positively correlated to an amplitude value of the ith element. ### Claim 9 (depends on 7) The user equipment according to claim 7, wherein a value of N is a value pre-agreed on between the UE and the network device. ### Claim 10 (depends on 7) The user equipment according to claim 7, wherein when i≠N, Ni=Nbase−Nadd,i, wherein Nbase is a base quantity of bits occupied by the quantized value of the ith element, and Nadd,i is a additional quantity of bits occupied by the quantized value of the ith element. ### Claim 11 A computer program product comprising a non-transitory computer-readable medium storing computer executable instructions, wherein the instructions comprise: instructions for determining a codebook of CSI at each transport layer of user equipment (UE), wherein the codebook of the CSI at each transport layer of the UE is: W=W1×W2, wherein W is the codebook of the CSI at each transport layer of the UE, W1 is a level-1 codebook, W1=[b1 b2 . . . bK], bi and W1 represents a codeword, K is a quantity of columns of W1, K is a positive integer greater than or equal to 1, W2 is a level-2 codebook, W2 is represented as W2=[X1 X2 . . . XK]T, an element Xi in W2 is a weighting coefficient corresponding to bi in W1, and i is an integer greater than or equal to 1 and less than or equal to K; instructions for determining a quantity Ni of bits occupied by a quantized value of an ith element in W2, wherein quantized values of at least two elements in W2 occupy different quantities of bits; and instructions for feeding back the quantized value of the ith element to a network device based on Ni. ### Claim 12 (depends on 11) The computer program product according to claim 11, further comprising: instructions for performing normalization processing on W2 based on an Nth element in W2, wherein N is an integer greater than or equal to 1 and less than or equal to K; and instructions for determining that Ni=0 when i=N. ### Claim 13 (depends on 12) The computer program product according to claim 12, wherein when i≠N, a value of Ni is positively correlated to an amplitude value of the ith element. ### Claim 14 (depends on 12) The computer program product according to claim 12, wherein a value of N is a value pre-agreed on between the UE and the network device. ### Claim 15 (depends on 12) The computer program product according to claim 12, wherein when i≠N, Ni=Nbase+Nadd,i, wherein Nbase base is a base quantity of bits occupied by the quantized value of the ith element, and Nadd,i is a additional quantity of bits occupied by the quantized value of the ith element.