US 11,736,902 B2
Peak to sigma ratio measurement with active geo-location for wireless local area network devices
Mark Passler, Boca Raton, FL (US); Graham K. Smith, Boca Raton, FL (US); Ryan Busser, Fort Lauderdale, FL (US); Olivia Turner, Pompano Beach, FL (US); and Steven Romanow, Sunrise, FL (US)
Assigned to SR Technologies, Inc., Sunrise, FL (US)
Filed by SR Technologies, Inc., Sunrise, FL (US)
Filed on Dec. 1, 2022, as Appl. No. 18/72,898.
Application 18/072,898 is a continuation of application No. 17/380,662, filed on Jul. 20, 2021, granted, now 11,546,735.
Claims priority of provisional application 63/069,946, filed on Aug. 25, 2020.
Prior Publication US 2023/0087126 A1, Mar. 23, 2023
Int. Cl. H04W 4/029 (2018.01); H04W 72/044 (2023.01); G01S 5/02 (2010.01); H04B 7/185 (2006.01); G01S 5/14 (2006.01)
CPC H04W 4/029 (2018.02) [G01S 5/0221 (2013.01); G01S 5/14 (2013.01); H04B 7/18502 (2013.01); H04W 72/0466 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method in a first wireless device (WD) to discriminate between valid round trip time (RTT) measurements arising from reception of a signal from a second WD and false RTT measurements arising from noise, the method comprising:
transmitting a plurality of ranging signals to the second WD;
receiving from the second WD a plurality of ranging response signals responsive to the plurality of ranging signals; and
for each ranging response signal of the plurality of ranging response signals:
determining a sum of correlations, each correlation being between an expected bit sequence and a received bit sequence in the ranging response signal;
determining a standard deviation of the sum of correlations;
determining a first ratio of a peak value of the sum of correlations to the standard deviation to obtain a peak to standard deviation ratio (PSR); and
rejecting an RTT measurement corresponding to the peak value of the sum correlations when the PSR is less than a threshold.