Patent ID: 9681267
Date: 2017-06-13
CPC Classifications: G01S,H04L,H04W

Claim:
1. A method comprising: receiving, at a wireless device, signals that are transmitted at different times, each of the signals having a different carrier frequency and representing a different subchannel of a wireless channel; determining estimated magnitudes of the subchannels based respectively on the signals; determining estimated group delays of the subchannels based respectively on the signals, wherein determining the estimated group delays comprises computing phase angles of a respective subchannel of the subchannels based on a Fourier transformation of a respective signal of the signals and a Fourier transformation of a reference signal, and applying a fit function to the phase angles to produce an estimated group delay of the respective subchannel; determining an estimated channel frequency response of the wireless channel based on the estimated magnitudes and the estimated group delays; determining a propagation delay of the signals based on the estimated channel frequency response; and generating position information based on the propagation delay.