Patent ID: 8068850

Claim:
A method of locating a transmitter, comprising the steps of: a) receiving a calibration signal at a plurality of receiving stations; b) establishing a communications link between a control station and each of the plurality of receiving stations, the communications link having a switchable input at the receiving station to transmit one of a received radiated signal and the received calibration signal, the switchable input switched in response to a user-activated signal; c) storing a communications link delay for each receiving station at the control station; d) receiving a radiated signal from a transmitter having an unknown location, the radiated signal received by at least two of the plurality of receiving stations; e) transmitting a user-defined portion of the radiated signal from at least two of the plurality of receiving stations to the control station over the communications links; f) recording the time of arrival of each radiated signals at the control station; g) if a user-activated signal is received to switch the input of the communications links, switching the input of the communications links that transmitted the radiated signal in step (e) from the received radiated signal to the calibration signal, otherwise proceeding to step (k); h) transmitting the calibration signal to the control station over the communications link, the transmission of the calibration signal at each of the receiving stations in step (g) timed to begin at the same time using a timing signal; i) calculating the communications link delay for each receiving station by subtracting the start time from the time the calibration signal from each receiving station was received; j) recording the calculated communications link delay for each receiving station at the control station; k) for each recorded time of arrival of the radiated signal from the at least two receiving stations, subtracting the communications link delay for the respective receiving station from the recorded time of arrival of the radiated signal for the respective receiving station; and l) locating the unknown transmitter by calculating the time difference of arrival of the radiated signal from the at least two receiving stations.