# US 9,883,490 B1 · Implicit sounding for OFDMA operation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,883,490 B1 - Document ID: US9883490B1 - Status: Granted - Kind: B1 - Application number: 15/007,020 - Filed: 2016-01-26 - Granted: 2018-01-30 - Earliest claimed: 2015-01-26 - Assignees: Newracom, Inc. - Applicants: Newracom, Inc. - Inventors: Ahmad Reza Hedayat - Web page: https://patentgrep.com/patent/US9883490B1 ## CPC - H04W 52/0235: {where the received signal is a power saving command} - H04L 5/0007: {the frequencies being orthogonal, e.g. OFDM(A) or DMT} - H04L 5/0057: {Physical resource allocation for CQI} - H04L 5/0091: {Signalling for the administration of the divided path, e.g. signalling of configuration information} - H04W 52/0216: {using a pre-established activity schedule, e.g. traffic indication frame} - H04W 52/0219: {where the power saving management affects multiple terminals} - H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA - H04W 72/542: using measured or perceived quality - H04W 84/12: WLAN [Wireless Local Area Networks] - Y02D 30/70: in wireless communication networks - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - 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 A method for communication in a wireless local area network comprises receiving, at a first device, a control frame from a second device. The method further comprises determining, by the first device using the control frame, a channel state information (CSI) for each of a plurality of sub bands of a bandwidth of the control frame, and allocating, by the first device to the second device, one or more sub bands from the plurality of sub bands based on the determination, the one or more sub bands to be allocated to the second device for transmitting data to the second device from the first device via an Orthogonal Frequency Division Multiple Access (OFDMA) frame. ## Claims ### Claim 1 A method for communication in a wireless local area network, the method comprising: receiving, at a first device, a control frame using a plurality of sub bands of a widest allowed bandwidth from a second device; determining, by the first device using the control frame, a channel state information (CSI) for each of a plurality of sub bands of a bandwidth of the control frame; and allocating, by the first device to the second device, one or more sub bands from the plurality of sub bands based on the determination, the one or more sub bands allocated to the second device for transmitting data to the second device from the first device via an Orthogonal Frequency Division Multiple Access (OFDMA) frame, wherein the control frame is an Orthogonal Frequency Division Multiplexing (OFDM) frame having a bandwidth greater than 20 MHz, wherein the control frame is a power save (PS) Poll frame, and wherein the widest allowed bandwidth is determined by determining whether one or more of a secondary 80 MHz channel, a secondary 40 MHz channel, and a secondary 20 channel is sensed busy during a Point Coordination Function Interframe Space (PIFS) time before transmission of the PS-Poll frame, wherein the determination is made when the first device indicates that the first device permits transmission by the second device of the control frame using the widest allowed bandwidth. ### Claim 2 (depends on 1) The method of claim 1, wherein the first bandwidth is one of a 40 MHz, an 80 MHz, an 80+80 MHz, and a 160 MHz bandwidth. ### Claim 3 (depends on 1) The method of claim 1, further comprising: transmitting to the second device by the first device a downlink (DL) frame prior to the first device receiving the control frame, and wherein the first bandwidth is a widest allowed bandwidth between the first device and the second device. ### Claim 4 (depends on 3) The method of claim 3, wherein the widest allowed bandwidth is a widest continuous bandwidth that is available for communications between the second device and the first device. ### Claim 5 (depends on 3) The method of claim 3, wherein the DL frame includes a block acknowledgement request (BAR) frame. ### Claim 6 (depends on 3) The method of claim 3, wherein the DL frame includes a bandwidth indicator that indicates the first bandwidth. ### Claim 7 A system for communication in a basic service set (BSS), the system comprising: a radio frequency (RF) transceiver; one or more processors; and a non-transitory computer readable medium comprising computer executable instructions which, when executed by the one or more processors, causes the system to: indicate that a station is permitted to transmit a control frame using a widest allowed bandwidth; receive a control frame using a plurality of sub bands of the widest allowed bandwidth from the station; determine a channel strength for each of a plurality of sub bands associated with a bandwidth of the control frame; allocate to the station one or more sub bands from the plurality of sub bands based, at least in part, on the determination, the one or more sub bands to be allocated to the station for transmitting data to the station; and transmit the data using the one or more allocated sub bands and via an Orthogonal Frequency Division Multiple Access (OFDMA) frame, wherein the control frame is an Orthogonal Frequency Division Multiplexing (OFDM) frame having a bandwidth greater than 20 MHz, wherein the control frame is a power save (PS) Poll frame, and wherein the widest allowed bandwidth is determined by determining whether one or more of a secondary 80 MHz channel, a secondary 40 MHz channel, and a secondary 20 channel is sensed busy during a Point Coordination Function InterFrame Space (PIFS) time before transmission of the PS-Poll frame, wherein the determination of the widest allowed bandwidth is made in response to the indication that the station is permitted to transmit the control frame using the widest allowed bandwidth. ### Claim 8 (depends on 7) The system of claim 7, wherein the bandwidth is one of a 40 MHz, an 80 MHz, an 80+80 MHz, and a 160 MHz bandwidth. ### Claim 9 A method for communication between devices in a wireless network, the method comprising: determining, by a first device, a widest allowed bandwidth for transmitting a control frame to a second device; transmitting, by the first device, the control frame to the second device using the widest allowed bandwidth, including using a plurality of sub bands of the widest allowed bandwidth to transmit the control frame; and receiving, by the first device, data from the second device via an Orthogonal Frequency Division Multiple Access (OFDMA) frame and using one or more sub bands selected from the plurality of sub-bands, the one or more sub-bands having been selected based on channel strength information (CSI) determinations made for each of the plurality of sub bands, wherein the control frame is an Orthogonal Frequency Division Multiplexing (OFDM) frame having a bandwidth greater than 20 MHz, wherein the control frame is a power save (PS) Poll frame, and wherein determining the widest allowed bandwidth includes determining whether one or more of a secondary 80 MHz channel, a secondary 40 MHz channel, and a secondary 20 channel is sensed busy during Point Coordination Function Interframe Space (PIFS) time before transmission of the PS-Poll frame, wherein the determination is made when the second device indicates that the second device permits transmission by the first device of the control frame using the widest allowed bandwidth. ### Claim 10 (depends on 9) The method of claim 9, wherein the widest allowed bandwidth is a widest continuous bandwidth that is available for communications between the second device and the first device. ### Claim 11 (depends on 9) The method of claim 9, further comprising: processing, by the first device, a downlink frame received from the second device prior to transmission of the control frame, wherein the downlink frame includes an indicator to use the widest available bandwidth for transmission of the control frame. ### Claim 12 (depends on 9) The method of claim 9, wherein the widest allowed bandwidth is determined based on a downlink (DL) frame received from the access point. ### Claim 13 (depends on 12) The method of claim 12, wherein determining the widest allowed bandwidth includes determining a bandwidth of the DL frame. ### Claim 14 (depends on 12) The method of claim 12, wherein determining the widest allowed bandwidth includes sensing an explicit bandwidth indicator included in the DL frame.