Patent ID: 6112095
Filing Date: 2000-08-29
Classification: G01C,G01S,H04L,H04W

Abstract:
In a system for wireless transmitter location finding, a method for calculating a set of likely locations of a transmitter, the method comprising:(a) measuring at a base station a signal covariance R associated with the transmitter;(b) evaluating a function B(.theta.) that measures an energy of the signal covariance R in an angular direction .theta. relative to the base station, wherein the evaluation of B(.theta.) uses an antenna array vector a(.theta.);(c) calculating a distance G between the function B(.theta.) and a function B.sub.k (.theta.), where B.sub.k (.theta.) measures an energy of a calibrated signal covariance R.sub.k in the angular direction .theta. relative to the base station, wherein the evaluation of B(.theta.) uses an antenna array vector a(.theta.), and wherein R.sub.k is a calibrated signal covariance associated with a location index k; and(d) selecting a set of location indices k such that the distance G between B and B.sub.k is small.