Target location from the estimated instantaneous received frequency

Abstract

Presented is a method to blindly estimate the location of a transmitter from the signal observed by a single moving receiver. This process is based on the observation that the observed Doppler characteristics are essentially uniquely determined by the transmission frequency, the location of the transmitter, and the time-varying flight path of the receiver. We accurately estimate the instantaneous frequency of the received signal and blindly calculate the transmitted frequency from the received signal and the instantaneous position and velocity of the receiver. The transmitter location is then estimated by minimizing a cost function representing the difference between the Doppler characteristics calculated from the relative geometry of the transmitter and receiver and the Doppler characteristics estimated from the received signal. The method has the advantages that only one receiving antenna is required and the emitter may be located with no a priori knowledge of the emitter location or frequency. In addition, the process is essentially independent of the flight path of the receiver.