# US 11,451,283 B2 · Channel smoothing with TX beamforming > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,451,283 B2 - Document ID: US11451283B2 - Status: Granted - Kind: B2 - Application number: 17/306,826 - Filed: 2021-05-03 - Published: 2021-11-25 - Granted: 2022-09-20 - Earliest claimed: 2020-05-21 - Assignees: Avago Technologies International Sales Pte. Limited - Applicants: Avago Technologies International Sales Pte. Limited - Inventors: Roy Oren; Daniel Stopler; Shimon Benjo - Web page: https://patentgrep.com/patent/US11451283B2 ## CPC - H04B 7/0634: {Antenna weights or vector/matrix coefficients} - H04B 7/0617: {for beam forming} - H04B 7/0641: {Differential feedback} - H04B: TRANSMISSION ## Abstract A method for channel smoothing with transmit beamforming includes transmitting, by a first device, a non-data-packet (NDP) frame to a second device. The method also includes receiving, by the second device, the NDP frame and transmitting a compressed report to the first device. The method further includes receiving, by the first device, the compressed report and deriving a first beamforming matrix from the compressed report. A second beamforming matrix is generated employing a processing known to the second device, and a data frame is transmitted to the second device using the second beamforming matrix. ## Claims ### Claim 1 A method for channel smoothing with transmit beamforming, the method comprising: transmitting a non-data-packet (NDP) frame to a device, wherein the NDP frame causes the device to estimate a channel, the estimated channel based on a physical channel and input noise; receiving, from the device, a compressed report; deriving a first beamforming matrix and the estimated channel from the compressed report; generating, based on the first beamforming matrix and the estimated channel, a second beamforming matrix by a process known to the device; and transmitting, using the second beamforming matrix, a data frame to the device. ### Claim 2 (depends on 1) The method of claim 1, wherein the estimated channel comprises a communication channel with the device. ### Claim 3 (depends on 2) The method of claim 2, wherein the first beamforming matrix is configured for use with beam steering based on the compressed report. ### Claim 4 (depends on 3) The method of claim 3, further comprising uncompressing the first beamforming matrix using a reciprocal process of a compression used by the device. ### Claim 5 (depends on 4) The method of claim 4, further comprising: applying a linear interpolation on the uncompressed first beamforming matrix; and mitigating, based on the linear interpolation, grouping of Ng adjacent carriers. ### Claim 6 (depends on 1) The method of claim 1, further comprising applying, while transmitting the data frame, different gains for different antennas. ### Claim 7 (depends on 1) The method of claim 1, further generating the second beamforming matrix comprises reconstructing the second beamforming matrix based on the compressed report. ### Claim 8 (depends on 7) The method of claim 7, wherein the data frame comprises one or more data streams that causes the device to estimate a pre-beamforming channel. ### Claim 9 (depends on 8) The method of claim 8, further comprising applying the reconstructed second beamforming matrix to the estimated pre-beamforming channel. ### Claim 10 (depends on 1) The method of claim 1, wherein the compressed report comprises a steering matrix used to focus energy on the device. ### Claim 11 A semiconductor substrate, comprising: transmitter circuitry; receiver circuitry; memory circuitry; and processing circuitry configured to execute code stored on the memory circuitry that causes the processing circuitry to; transmit, using the transmitter circuitry, a non-data-packet (NDP) frame to a device, wherein the NDP frame causes the device to estimate a channel, the estimated channel based on a physical channel and input noise; receive, using the receiver circuitry, a compressed report from the device; derive a first beamforming matrix and the estimated channel from the compressed report; generate, based on the first beamforming matrix and the estimated channel, a second beamforming matrix by a process known to the device; and transmit, using the second beamforming matrix, a data frame to the device. ### Claim 12 (depends on 11) The semiconductor substrate of claim 11, wherein the processing circuitry is further configured to execute code to uncompress the first beamforming matrix using a reciprocal process of a compression used by the device. ### Claim 13 (depends on 12) The semiconductor substrate of claim 12, wherein the processing circuitry is further configured to execute code to: apply a linear interpolation on the uncompressed first beamforming matrix; and mitigate, based on the linear interpolation, grouping of Ng adjacent carriers. ### Claim 14 (depends on 11) The semiconductor substrate of claim 11, wherein the processing circuitry is further configured to execute code to apply, while transmitting the data frame, different gains for a plurality of antennas. ### Claim 15 (depends on 11) The semiconductor substrate of claim 11, wherein the processing circuitry is further configured to execute code to reconstruct the second beamforming matrix by estimating the physical channel between the device and one or more of the receiver circuitry and the transmitter circuitry. ### Claim 16 (depends on 15) The semiconductor substrate of claim 15, wherein the processing circuitry is further configured to execute code to estimate a pre-beamforming channel. ### Claim 17 (depends on 16) The semiconductor substrate of claim 16, wherein the processing circuitry is further configured to execute code to apply the reconstructed second beamforming matrix to the estimated pre-beamforming channel. ### Claim 18 A multiantenna access point comprising: processing circuitry configured to: transmit a non-data-packet (NDP) frame to a wireless communication device, wherein the NDP frame causes the wireless communication device to estimate a channel, the estimated channel based on a physical channel and input noise; receive, from the wireless communication device, a compressed report; derive a beamforming matrix and the estimated channel from the compressed report; generate, based on the beamforming matrix and the estimated channel, a V matrix employing a processing that is known to the wireless communication device; and transmit, using the V matrix, a data frame to the wireless communication device. ### Claim 19 (depends on 18) The multiantenna access point of claim 18, wherein the processing circuitry is configured to: reconstruct the V matrix based on a knowledge of the processing used by the wireless communication device; estimate a pre-beamforming channel; and apply the reconstructed V matrix to the estimated pre-beamforming channel. ### Claim 20 (depends on 19) The multiantenna access point of claim 19, wherein the reconstructed V comprises beam steering that is applied on the estimated pre-beamforming channel.