Patent ID: 7545325

Claim:
A method of geolocating a transmitter, comprising the steps of: a) receiving a first wideband signal at a first receiver from transmitter, where the first signal received at the first receiver is designated as s 1 ; b) receiving the first signal at a second receiver from the transmitter, where the first signal received at the second receiver is designated as s 2 ; c) calculating a difference (T 2 −T 1 ) in propagation delays between the transmitter and the first receiver and the second receiver, where T 1 is the propagation delay from the transmitter to the first receiver, and where T 2 is the propagation delay from the transmitter to the second receiver comprising the steps of: i) determining, digitally, values for user-definable variables β and Δ that maximize |∫S 2 *(τ)S 1 (β(τ−Δ))dτ|, where S 1 (τ)=s 1 (τ+T 1 ), where S 2 (τ)=s 2 (τ+T 1 ), where S 2 * is the complex conjugation of S 2 , and where τ is a user-definable time; ii) setting δ equal to the value determined for variable Δ in step (i); and iii) setting (T 2 −T 1 ) equal to δ; and d) calculating a difference in radial velocities (V 2 −V 1 ) of the receivers relative to the transmitter using a scale factor b based on time of the received signal, where V 1 is the radial velocity of the first receiver relative to the transmitter, and where V 2 is the radial velocity of the second receiver relative to the transmitter; and e) geolocating the transmitter using the results of step (c) and (d).