Patent ID: 8111193

Claim:
A method comprising: obtaining a signal from antenna elements of a multi-antenna receiver; and determining whether the signal is more likely associated with propagation from a transmitter via a line-of-sight (LOS) radio channel or a non-line-of-sight (NLOS) radio channel by performing one or more selected from the group comprising: (1) determining the angular power spectrum of the signal and comparing the angular power spectrum of the signal with known angular power spectrums of LOS and/or NLOS signals; and (2) determining the power variance of the signal and comparing the power variance of the signal with known power variance values of LOS and/or NLOS signals; wherein the method further comprises: using a model including parameters selected according to whether the signal is more likely associated with an LOS or an NLOS radio channel to estimate the distance between the receiver and the transmitter.