US Patent No. 10,694,499


Patent No. 10,694,499
Issue Date June 23, 2020
Title Location Estimation Using Multi-user Multiple Input Multiple Output In A Wireless Local Area Network
Inventorship Ganesh Venkatesan, Hillsboro, OR (US)
Chittabrata Ghosh, Fremont, CA (US)
Assignee Intel IP Corporation, Santa Clara, CA (US)

Claim of US Patent No. 10,694,499

1. An apparatus of a responding station (STA) comprising: memory; and processing circuitry coupled to the memory, the processing circuitry configured to:encode a fine timing measurement (FTM) initiate (FTI) frame, the FTI frame comprising M0 message uplink resource allocations for each of a plurality of initiator STAs to transmit M0 messages to the responding STA, wherein the FTI frame is a trigger frame, wherein the M0 messages are null data packets;
configure the responding STA to transmit the FTI frame to the plurality of initiator STAs;
decode M0 messages from each of the plurality of initiator STAs in accordance with the M0 message uplink resource allocations, wherein the M0 messages are received at the responding STA at times T2 in accordance with multi-user multiple-input multiple-output (MU-MIMO);
encode frames for transmission after the M0 messages, wherein the frames are to be transmitted at a time T3;
decode M1 messages from the plurality of initiator STAs, wherein the M1 messages comprise a corresponding time T1 when a corresponding M0 message was transmitted by a corresponding initiator STA of the plurality of initiator STAs and a corresponding time T4 when a corresponding frame of the frames was received by the corresponding initiator STA; and
determine a distance of the responding STA from each of the corresponding initiator STAs based on ((the corresponding time T4?the time T3)?(the corresponding time T2?a corresponding time T1))/(2 times a speed of light in free space).