# US 2021/0242910 A1 · Communication device and communication method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0242910 A1 - Document ID: US20210242910A1 - Status: Published application - Kind: A1 - Application number: 17/049,231 - Filed: 2019-04-19 - Published: 2021-08-05 - Earliest claimed: 2018-04-23 - Assignees: Panasonic Intellectual Property Corporation of America - Applicants: Panasonic Intellectual Property Corporation of America - Inventors: Lei HUANG; Hiroyuki MOTOZUKA; Takenori SAKAMOTO - Web page: https://patentgrep.com/patent/US20210242910A1 ## CPC - H04B 7/0417: Feedback systems - H04B 7/0452: Multi-user MIMO systems - H04B 7/0621: {Feedback content} - H04B 7/063: {Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection} - H04B 7/0628: {Diversity capabilities} - Y02D 30/70: in wireless communication networks - H04B: TRANSMISSION - Y02D: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE ## Abstract According to a communication method of the present disclosure, a responder, after the end of transmission sector sweep (TXSS), receives from an initiator a first feedback frame including a BF training type FIELD indicating whether or not to implement a beam forming training (BFT) of a single user multi-input multi-output (SU-MIMO). If the BF training type FIELD indicates that a BFT of the SU-MIMO is to be implemented, the responder transmits to the initiator a second feedback frame based on the result of the TXSS and including a signal to noise ratio (SNR) and a sector identifier (ID) order. The initiator implements the BFT of the SU-MIMO between the initiator and the responder on the basis of the SNR and the sector ID order. ## Claims ### Claim 1 A communication method, comprising: transmitting, by an initiator, a first feedback frame to a responder, the first feedback frame including a BF training type FIELD indicating whether or not beamforming training (BFT) for Single User Multi-Input Multi-Output (SU-MIMO) is performed after a transmission sector sweep (TXSS) ends; receiving, by the responder, the first feedback frame, and transmitting, by the responder, second feedback frame to the initiator when the BF training type FIELD indicates that the BFT for SU-MIMO is performed, the second feedback frame including a Signal to Noise Ratio (SNR) and a Sector Identifier (ID) Order based on a result of the TXSS; and receiving, by the initiator, the second feedback frame, and performing, by the initiator, the BFT for SU-MIMO between the initiator and the responder based on the SNR and the sector ID order. ### Claim 2 (depends on 1) The communication method according to claim 1, wherein the TXSS is carried out by using one of DMG Beacon, Sector Sweep (SSW), Short SSW, and DMG Beam Refinement Protocol (BRP)-TX. ### Claim 3 (depends on 1) The communication method according to claim 1, wherein the BF training type FIELD is set to 0 when indicating BFT for SISO, to 1 when indicating the BFT for SU-MIMO, or to 2 when indicating BFT for MU-MIMO. ### Claim 4 A communication method for an initiator, the communication method comprising: transmitting a feedback frame to a responder, the feedback frame including a BF training type FIELD indicating whether or not BFT for SU-MIMO is performed after TXSS ends; and when a second feedback frame including an SNR and a sector ID order based on a result of the TXSS is received from the responder, performing the BFT for SU-MIMO between the initiator and the responder based on the SNR and the sector ID order. ### Claim 5 (depends on 4) The communication method for the initiator according to claim 4, wherein the TXSS is carried out by using one of DMG Beacon, Sector Sweep (SSW), Short SSW, and DMG Beam Refinement Protocol (BRP)-TX. ### Claim 6 (depends on 4) The communication method for the initiator according to claim 4, wherein the BF training type FIELD is set to 0 when indicating BFT for SISO, to 1 when indicating the BFT for SU-MIMO, or to 2 when indicating BFT for MU-MIMO. ### Claim 7 A communication method for a responder, the communication method comprising: receiving a first feedback frame from an initiator, the first feedback frame including a BF training type FIELD indicating whether or not beamforming training (BFT) for Single User Multi-Input Multi-Output (SU-MIMO) is performed after transmission sector sweep (TXSS) ends; transmitting second feedback frame to the initiator when the BF training type FIELD indicates that the BFT for SU-MIMO is performed, the second feedback frame including a Signal to Noise Ratio (SNR) and a sector Identifier (ID) order based on a result of the TXSS; and performing the BFT for SU-MIMO between the initiator and the responder based on the SNR and the sector ID order. ### Claim 8 (depends on 7) The communication method for the responder according to claim 7, wherein the TXSS is carried out by using one of DMG Beacon, Sector Sweep (SSW), Short SSW, and DMG Beam Refinement Protocol (BRP)-TX. ### Claim 9 (depends on 7) The communication method for the responder according to claim 7, wherein the BF training type FIELD is set to 0 when indicating BFT for SISO, to 1 when indicating the BFT for SU-MIMO, or to 2 when indicating BFT for MU-MIMO. ### Claim 10 An initiator communication apparatus, comprising: a MAC circuit, which, in operation, generates a first feedback frame including a BF training type FIELD indicating whether or not BFT for SU-MIMO is performed after TXSS ends; a transmission circuit, which, in operation, transmits the first feedback frame to a responder; and a reception circuit, which, in operation, receives second feedback frame from the responder, wherein, when the second feedback frame includes an SNR and a sector ID order based on a result of the TXSS from the responder, the MAC circuit performs BFT with the responder using the transmission circuit and the reception circuit based on the SNR and the sector ID order. ### Claim 11 (depends on 10) The initiator communication apparatus according to claim 10, wherein the TXSS is carried out by using one of DMG Beacon, Sector Sweep (SSW), Short SSW, and DMG Beam Refinement Protocol (BRP)-TX. ### Claim 12 (depends on 11) The initiator communication apparatus according to claim 11, wherein the BF training type FIELD is set to 0 when indicating BFT for SISO, to 1 when indicating the BFT for SU-MIMO, or to 2 when indicating BFT for MU-MIMO. ### Claim 13 A responder communication apparatus, comprising: a reception circuit, which, in operation, receives a first feedback frame from an initiator, the first feedback frame including a BF training type FIELD indicating whether or not beamforming training (BFT) for Single User Multi-Input Multi-Output (SU-MIMO) is performed after transmission sector sweep (TXSS) ends; a MAC circuit, which, in operation, generates second feedback frame when the BF training type FIELD indicates that the BFT for SU-MIMO is performed, the second feedback frame including a Signal to Noise Ratio (SNR) and a sector Identifier (ID) order based on a result of the TXSS; and a transmission circuit, which, in operation, transmits the second feedback frame to the initiator, wherein, after the transmission circuit transmits the second feedback frame to the initiator, the MAC circuit performs the BFT for SU-MIMO between the responder and the initiator using the transmission circuit and the reception circuit based on the SNR and the sector ID order. ### Claim 14 (depends on 13) The responder communication apparatus according to claim 13, wherein the TXSS is carried out by using one of DMG Beacon, Sector Sweep (SSW), Short SSW, and DMG Beam Refinement Protocol (BRP)-TX. ### Claim 15 (depends on 13) The responder communication apparatus according to claim 13, wherein the BF training type FIELD is set to 0 when indicating BFT for SISO, to 1 when indicating the BFT for SU-MIMO, or to 2 when indicating BFT for MU-MIMO.