Patent ID: 9641974
Date: 2017-05-02
CPC Classifications: G01S,H04W,Y02D

Claim:
1. A method for obtaining a position fix for a human body comprising, at a first mobile device: detecting a presence of a second mobile device, said first mobile device being located on a first location of said human body and said second mobile device being located on a second location of said human body different from the first location on said human body; acquiring by said first mobile device a first signal from a first fixed transmitter device to obtain one or more first observations of said first signal, the one or more first observations of said first signal comprising one or more first observations of a received signal strength of said first signal or one or more first observations of a time of arrival of said first signal, or a combination thereof; acquiring by said first mobile device a second signal from a second fixed transmitter device to obtain one or more first observations of said second signal, the one or more first observations of said second signal comprising one or more first observations of a received signal strength of said second signal or one or more first observations of a time of arrival of said second signal, or a combination thereof; receiving one or more messages from the second mobile device through a wireless link between said first mobile device and said second mobile device comprising one or more second observations of the first signal transmitted from the first fixed transmitter device, wherein the one or more second observations of the first signal transmitted by the first fixed transmitter device are obtained by the second mobile device and comprise one or more second observations of said received signal strength of said first signal or one or more first observations of said time of arrival of said first signal, or a combination thereof, and one or more second observations of the second signal from the second fixed transmitter device, wherein the one or more second observations of the second signal transmitted by the second fixed transmitter device are obtained by the second mobile device and comprise one or more second observations of said received signal strength of said second signal or one or more second observations of said time of arrival of said second signal, or a combination thereof; selecting at least one of the one or more first observations of said first signal for computing the position fix for said human body based at least in part, on a first indicator, the first indicator being indicative of a utility of the one or more first observations of said first signal relative to a second indicator, the first indicator being based, at least in part, on one or more of the following factors: a degree to which the first mobile device is concealed or obscured from receiving the first signal; a measured first received signal strength; a first measured signal to noise ratio; a first measurement of a presence of multipath; or a first measurement of a presence of signal interference, the second indicator being indicative of a utility of the one or more second observations of said first signal; selecting at least one of the one or more second observations of said second signal for computing said position fix for said human body based at least in part, on a third indicator, the third indicator being indicative of a utility of the one or more first observations of said second signal relative to a fourth indicator, the third indicator being based, at least in part, on one or more of the following factors: a second degree to which the first mobile device is concealed or obscured from receiving the first signal; a second measured received signal strength; a second measured signal to noise ratio; a second measurement of a presence of multipath; or a second measurement of a presence of signal interference, the fourth indicator being indicative of a utility of the one or more second observations of said second signal; and combining the selected at least one of the one or more first observations of said first signal and the selected at least one of the one or more second observations of second signal for determining said position fix.