# US 9,520,964 B2 · Method for reporting channel information based on link adaptation in wireless local area network and the apparatus for the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,520,964 B2 - Document ID: US9520964B2 - Status: Granted - Kind: B2 - Application number: 14/993,363 - Filed: 2016-01-12 - Published: 2016-05-05 - Granted: 2016-12-13 - Earliest claimed: 2010-11-26 - Assignees: LG Electronics Inc. - Applicants: LG Electronics Inc. - Inventors: Ill Soo Sohn; Yong Ho Seok; Kyoung Young Song; Dae Won Lee; Byeong Woo Kang - Web page: https://patentgrep.com/patent/US9520964B2 ## CPC - H04L 1/0003: {by switching between different modulation schemes} - H04L 1/0025: {Transmission of mode-switching indication} - H04L 1/0026: {Transmission of channel quality indication} - H04L 1/0027: {Scheduling of signalling, e.g. occurrence thereof} - H04L 1/06: using space diversity - H04W 24/10: Scheduling measurement reports {; Arrangements for measurement reports} - H04W 72/04: Wireless resource allocation - 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 A method and a device for reporting a modulation and coding scheme (MCS) feedback in a wireless local area network are provided. A responding station receives, from a requesting station, a requesting Physical layer Protocol Data Unit (PPDU) for requesting a MCS feedback via a plurality of spatial streams. A recommended MCS is estimated under an assumption that the requesting station will transmit at least one first spatial stream among the plurality of spatial streams used for the requesting PPDU, The responding station transmits, to the requesting station, the MCS feedback including a recommended MCS field indicating the recommended MCS and a recommended stream field indicating a number of at least one recommended spatial stream. A number of the at least one first spatial stream used for estimating the recommended MCS is equal to the number of the at least one recommended spatial stream. ## Claims ### Claim 1 A method for reporting a modulation and coding scheme (MCS) feedback in a wireless local area network, the method comprising: receiving, by a responding station, from a requesting station, a requesting Physical layer Protocol Data Unit (PPDU) for requesting a MCS feedback via a plurality of spatial streams, wherein, in response to the responding station receiving the requesting PPDU, the method further comprises: estimating, by the responding station, a recommended MCS under an assumption that the requesting station will transmit at least one first spatial stream among the plurality of spatial streams used to receive the requesting PPDU; generating, by the responding station, the MCS feedback requested by the received requesting PPDU, wherein the generated MCS feedback includes: a recommended MCS field indicating the estimated recommended MCS, and a recommended stream field indicating a number of at least one recommended spatial stream; and transmitting, by the responding station, to the requesting station, the generated MCS feedback, wherein a number of the at least one first spatial stream used for estimating the recommended MCS is equal to the number of the at least one recommended spatial stream. ### Claim 2 (depends on 1) The method of claim 1, wherein the number of the at least one first spatial stream used for estimating the recommended MCS is less than a number of the plurality of spatial streams used to receive the requesting PPDU. ### Claim 3 (depends on 1) The method of claim 1, wherein the requesting PPDU includes an MCS request (MRQ) field that requests the responding station to provide the MCS feedback. ### Claim 4 (depends on 1) The method of claim 1, wherein the recommended stream field has 3 bits. ### Claim 5 (depends on 1) The method of claim 1, wherein the recommended MCS field has 4 bits. ### Claim 6 (depends on 1) The method of claim 1, wherein the requesting PPDU includes a stream indicator indicating the number of the plurality of spatial streams used for the requesting PPDU. ### Claim 7 A device configured to report a modulation and coding scheme (MCS) feedback in a wireless local area network, the device comprising: a transceiver configured to transmit and receive a radio signal; and, a processor operably coupled to the transceiver and configured to: control the transceiver to receive, from a requesting station, a requesting Physical layer Protocol Data Unit (PPDU) for requesting a MCS feedback via a plurality of spatial streams, wherein, in response to the transceiver receiving the requesting PPDU, the processor is further configured to: estimate a recommended MCS under an assumption that the requesting station will transmit at least one first spatial stream among the plurality of spatial streams used to receive the requesting PPDU; generate the MCS feedback requested by the received requesting PPDU, wherein the generated MCS feedback includes: a recommended MCS field indicating the estimated recommended MCS, and a recommended stream field indicating a number of at least one recommended spatial stream; and control the transceiver to transmit, to the requesting station, the generated MCS feedback, wherein a number of the at least one first spatial stream used for estimating the recommended MCS is equal to the number of the at least one recommended spatial stream. ### Claim 8 (depends on 7) The device of claim 7, wherein the number of the at least one first spatial stream used for estimating the recommended MCS is less than a number of the plurality of spatial streams used to receive the requesting PPDU. ### Claim 9 (depends on 7) The device of claim 7, wherein the requesting PPDU includes an MCS request (MRQ) field that requests the responding station to provide the MCS feedback. ### Claim 10 (depends on 7) The device of claim 7, wherein the recommended stream field has 3 bits. ### Claim 11 (depends on 7) The device of claim 7, wherein the recommended MCS field has 4 bits. ### Claim 12 (depends on 7) The device of claim 7, wherein the requesting PPDU includes a stream indicator indicating the number of the plurality of spatial streams used for the requesting PPDU.