# US 9,520,928 B2 · Including feedback information regarding an individual subband of a wireless channel > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,520,928 B2 - Document ID: US9520928B2 - Status: Granted - Kind: B2 - Application number: 14/481,360 - Filed: 2014-09-09 - Published: 2014-12-25 - Granted: 2016-12-13 - Earliest claimed: 2008-06-25 - Assignees: Apple Inc. - Applicants: Apple Inc. - Inventors: Sairamesh Nammi; Shankar Venkatraman; Gaurav Hemrajani; Ashvin Chheda; Lai King Tee; Neng Wang; Kathiravetpillai Sivanesan - Web page: https://patentgrep.com/patent/US9520928B2 ## CPC - H04B 7/0417: Feedback systems - H04B 7/0619: {using feedback from receiving side (feedback signaling for adaptive modulation/coding H04L1/0001)} - H04B 7/063: {Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection} - H04L 5/0096: {Indication of changes in allocation} - H04W 4/20: Services signaling; Auxiliary data signalling, i.e. transmitting data via a non-traffic channel - H04W 72/21: in the uplink direction of a wireless link, i.e. towards the network - 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 To report feedback information regarding a wireless channel, a mobile station determines whether a predefined condition is satisfied. In response to determining that the predefined condition is satisfied, feedback information regarding an individual one of plural subbands of the wireless channel is included in a first report to be sent to a base station. In response to determining that the predefined condition is not satisfied, aggregate feedback information regarding the plural subbands is included in a second report to be sent to the base station. ## Claims ### Claim 1 A method of reporting feedback information regarding a wireless channel comprising: determining, by a mobile station, whether a predefined condition is satisfied, wherein determining whether the predetermined condition is satisfied comprises determining whether a parameter of aggregate feedback information regarding plural subbands included in a prior report sent to a base station has not changed; in response to determining that the predefined condition is satisfied, including, in a first report to be sent to the base station, feedback information regarding an individual one of plural subbands of the wireless channel; and in response to determining that the predefined condition remains satisfied, including, in a second report to be sent to the base station, feedback information regarding a second individual one of plural subbands of the wireless channel. ### Claim 2 (depends on 1) The method of claim 1, further comprising in response to determining that the predefined condition is not satisfied, including, in a third report to be sent to the base station, aggregate feedback information regarding the plural subbands. ### Claim 3 (depends on 2) The method of claim 2, wherein the aggregate feedback information includes an average of the plurality of subbands. ### Claim 4 (depends on 1) The method of claim 1, wherein determining whether the predefined condition is satisfied comprises determining whether the mobile station is slow moving. ### Claim 5 (depends on 1) The method of claim 1, further comprising: including in the first report further feedback information regarding a second individual one of the plural subbands. ### Claim 6 (depends on 1) The method of claim 1, wherein the feedback information is for a closed loop MIMO (multiple input, multiple output) mode of operation. ### Claim 7 (depends on 6) The method of claim 6, wherein the feedback information included in the first report is for a first of plural codewords, and wherein the first report further includes feedback information for an individual subband for another one of the plural codewords. ### Claim 8 (depends on 1) The method of claim 1, wherein the feedback information in the first report for the individual subband comprises at least one of: a precoding matrix index (PMI); and channel quality indicator (CQI). ### Claim 9 A base station comprising: an interface to communicate wirelessly over a wireless channel with a mobile station; and a processor configured to: determine whether a predefined condition is satisfied, wherein to determine whether the predefined condition is satisfied the processor is further configured to determine whether a parameter of aggregate feedback information regarding plural subbands included in a prior report received from the mobile station has not changed; in response to determining that the predefined condition is satisfied, use individual feedback information for an individual subband of plural subbands of the wireless channel; and in response to determining that the predefined condition remains satisfied, use individual feedback information regarding a second individual one of plural subbands of the wireless channel. ### Claim 10 (depends on 9) The base station of claim 9, wherein the processor is further configured to: in response to determining that the predefined condition is not satisfied, including, use aggregate feedback information regarding the plural subbands. ### Claim 11 (depends on 9) The base station of claim 9, wherein to determine whether the predefined condition is satisfied the processor is further configured to: determine whether the mobile station is slow moving. ### Claim 12 (depends on 9) The base station of claim 9, wherein the individual feedback information or aggregate feedback information is used for downlink signaling and traffic data to be sent to the mobile station. ### Claim 13 (depends on 9) The base station of claim 9, wherein the individual feedback information comprises at least one of: an individual channel quality indicator (CQI); and an individual precoding matrix index (PMI). ### Claim 14 A mobile station comprising: an interface to communicate wirelessly over a wireless channel with a base station; and a processor configured to: determine whether a predefined condition is satisfied, wherein to determine whether the predefined condition is satisfied the processor is further configured to determine whether a parameter of aggregate feedback information regarding plural subbands included in a prior report sent to the base station has not changed; in response to determining that the predefined condition is satisfied, include, in a first report to be sent to the base station, individual feedback information regarding an individual one of plural subbands of the wireless channel; and in response to determining that the predefined condition remains satisfied, include, in a second report to be sent to the base station, feedback information regarding a second individual one of plural subbands of the wireless channel. ### Claim 15 (depends on 14) The mobile station of claim 14, wherein the processor is further configured to: in response to determining that the predefined condition is not satisfied, include, in a third report to be sent to the base station, aggregate feedback information regarding the plural subbands. ### Claim 16 (depends on 14) The mobile station of claim 14, wherein to determine whether the predefined condition is satisfied the processor is further configured to: determine whether the mobile station is slow moving. ### Claim 17 (depends on 14) The mobile station of claim 14, wherein the first report includes a bitmap identifying the plural subbands as being preferred subbands. ### Claim 18 (depends on 9) The base station of claim 9, wherein the parameter of aggregate feedback information regarding plural subbands included in a prior report is a data structure identifying preferred subbands. ### Claim 19 (depends on 1) The method of claim 1, wherein the parameter of aggregate feedback information regarding plural subbands included in a prior report is a data structure identifying preferred subbands. ### Claim 20 (depends on 14) The mobile station of claim 14, wherein the parameter of aggregate feedback information regarding plural subbands included in a prior report is a data structure identifying preferred subbands.