# US 11,451,279 B2 · Subband channel state information (CSI) omission for type-II CSI > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,451,279 B2 - Document ID: US11451279B2 - Status: Granted - Kind: B2 - Application number: 16/650,171 - Filed: 2018-09-29 - Published: 2020-07-23 - Granted: 2022-09-20 - Earliest claimed: 2017-10-02 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Liangming Wu; Yu Zhang; Chenxi Hao; Chao Wei; Wanshi Chen - Web page: https://patentgrep.com/patent/US11451279B2 ## CPC - H04B 7/0626: {Channel coefficients, e.g. channel state information [CSI]} - H04L 1/0026: {Transmission of channel quality indication} - H04B 7/0417: Feedback systems - H04B 7/0486: {taking channel rank into account} - H04B 7/063: {Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection} - H04B 7/0632: {Channel quality parameters, e.g. channel quality indicator [CQI]} - H04B 7/0639: {Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection} - H04L 1/003: {Adaptive formatting arrangements particular to signalling, e.g. variable amount of bits} - H04L 1/0031: {Multiple signaling transmission (H04L1/1664, F15 take precedence)} - H04L 1/1671: {the supervisory signal being transmitted together with control information} - H04L 5/0057: {Physical resource allocation for CQI} - H04W 24/10: Scheduling measurement reports {; Arrangements for measurement reports} - H04B: TRANSMISSION - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Certain aspects of the present disclosure generally relate to methods and apparatus for generating and reporting CSI. ## Claims ### Claim 1 A method for wireless communications, comprising: determining, in a two-part channel state information (CSI) reporting scheme, a first number M out of N subbands to use for feeding back CSI in a second CSI feedback part, wherein N represents a configured number of supported subbands for subband precoding matrix indicator (PMI) reporting; deciding, based on a rank indicator (RI) and a non-zero wideband amplitude (NZWA) per layer, which of the N subbands to omit from the M subbands; and reporting CSI feedback for the M subbands in the second CSI feedback part. ### Claim 2 (depends on 1) The method of claim 1, wherein the determination of M is based on a mapping rule using the RI and NZWA. ### Claim 3 (depends on 1) The method of claim 1, wherein the determination of M is based on a lookup table accessed based on the RI and NZWA. ### Claim 4 (depends on 3) The method of claim 3, wherein the mapping table is configured by a base station. ### Claim 5 (depends on 3) The method of claim 3, wherein the mapping table is associated with the configured or allocated resource for CSI reporting. ### Claim 6 (depends on 3) The method of claim 3, wherein the mapping table is generated differently depending on what resource is allocated for CSI feedback. ### Claim 7 (depends on 1) The method of claim 1, wherein the determination of M is performed to ensure the CSI feedback for the M subbands will fit based on a payload size of the second CSI feedback part. ### Claim 8 (depends on 7) The method of claim 7, wherein M is selected based on a maximum supported value for the payload size. ### Claim 9 (depends on 1) The method of claim 1, wherein: a first subband associated with a best CQI in a set of consecutive subbands is included in the M subbands; and a second subband associated with a worst CQI in the set of consecutive subbands is also included in the M subbands. ### Claim 10 (depends on 1) The method of claim 1, wherein: the subbands to include in the M subbands is based on a decimation pattern. ### Claim 11 (depends on 10) The method of claim 10, wherein: the subbands to include in the M subbands is also based on a CQI associated with the subbands. ### Claim 12 (depends on 10) The method of claim 10, wherein: the decimation pattern results in the inclusion of every other subband of a set of subbands. ### Claim 13 An apparatus for wireless communications, comprising: means for determining, in a two-part channel state information (CSI) reporting scheme, a first number M out of N subbands to use for feeding back CSI in a second CSI feedback part, wherein N represents a configured number of supported subbands for subband precoding matrix indicator (PMI) reporting; means for deciding, based on a rank indicator (RI) and a non-zero wideband amplitude (NZWA) per layer, which of the N subbands to omit from the M subbands; and means for reporting CSI feedback for the M subbands in the second CSI feedback part. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein the determination of M is based on a mapping rule using the RI and NZWA. ### Claim 15 (depends on 13) The apparatus of claim 13, wherein the determination of M is based on a lookup table accessed based on the RI and NZWA. ### Claim 16 (depends on 15) The apparatus of claim 15, wherein the mapping table is configured by a base station. ### Claim 17 (depends on 15) The apparatus of claim 15, wherein the mapping table is associated with the configured or allocated resource for CSI reporting. ### Claim 18 (depends on 15) The apparatus of claim 15, wherein the mapping table is generated differently depending on what resource is allocated for CSI feedback. ### Claim 19 (depends on 13) The apparatus of claim 13, wherein the determination of M is performed to ensure the CSI feedback for the M subbands will fit based on a payload size of the second CSI feedback part. ### Claim 20 (depends on 19) The apparatus of claim 19, wherein M is selected based on a maximum supported value for the payload size. ### Claim 21 (depends on 13) The apparatus of claim 13, wherein: a first subband associated with a best CQI in a set of consecutive subbands is included in the M subbands; and a second subband associated with a worst CQI in the set of consecutive subbands is also included in the M subbands. ### Claim 22 (depends on 13) The apparatus of claim 13, wherein: the subbands to include in the M subbands is based on a decimation pattern. ### Claim 23 (depends on 22) The apparatus of claim 22, wherein: the subbands to include in the M subbands is also based on a CQI associated with the subbands. ### Claim 24 (depends on 22) The apparatus of claim 22, wherein: the decimation pattern results in the inclusion of every other subband of a set of subbands. ### Claim 25 An apparatus for wireless communications, comprising: at least one processor configured to determine, in a two-part channel state information (CSI) reporting scheme, a first number M out of N subbands to use for feeding back CSI in a second CSI feedback part, wherein N represents a configured number of supported subbands for subband precoding matrix indicator (PMI) reporting and to decide, based on a rank indicator (RI) and a non-zero wideband amplitude (NZWA) per layer, which of the N subbands to omit from the M subbands; and a transmitter configured to transmit CSI feedback for the M subbands in the second CSI feedback part. ### Claim 26 A non-transitory computer readable medium having instructions stored thereon for: determining, in a two-part channel state information (CSI) reporting scheme, a first number M out of N subbands to use for feeding back CSI in a second CSI feedback part, wherein N represents a configured number of supported subbands for subband precoding matrix indicator (PMI) reporting; deciding, based on a rank indicator (RI) and a non-zero wideband amplitude (NZWA) per layer, which of the N subbands to omit from the M subbands; and reporting CSI feedback for the M subbands in the second CSI feedback part.