Patent ID: 7268728

Claim:
A method for locating a transmitter from which an electromagnetic signal is being received using a plurality of antennas and a plurality of receivers mounted on a moving platform, and indicating the geolocation and track of movement of the transmitter, and the geolocation of the transmitter when the transmitter is not moving, the method comprising the steps of: (a) storing a plurality of sets of digitized samples of the electromagnetic signal received with the antennas and receivers; (b) processing the plurality of digitized signal sample sets of step (a) to obtain a like plurality of signal array vectors; (c) performing a first analysis of the digitized signal sample sets and their signal array vectors to locate a distinctive point having a peak value that may indicate the geolocation of the source of the electromagnetic signal, the first analysis being performed using an equation that has velocity terms but setting the velocity terms equal to zero; (d) analyzing the peak value of the distinctive point from the first analysis to determine if the transmitter is moving or not moving, and when it is indicated that the transmitter is not moving that distinctive point identifies the geolocation of the transmitter; (e) performing a second analysis of the digitized signal sample sets and their signal array vectors when it is determined in step (d) that the transmitter is moving, using the equation mentioned in step (c) with the velocity terms not set equal to zero, and using the distinctive point located in step (c) as the starting point of the second analysis, the result of the second analysis yielding the initial geolocation of the moving transmitter at the start of formation of the signal sample sets in step (a), a velocity vector and a direction vector of the moving transmitter; and (f) calculating a track of movement of the moving transmitter using the geolocation determined in step (e), the velocity vector and the direction vector determined in step (e).