ABSTRACT
Localization of a source becomes a simple linear problem with the combined use of Doppler shift information frequency difference of arrival (FDoA) and time difference of arrival (TDoA). Weiss and other authors have shown that direct position determination (DPD) leads to more accurate estimates. Apart from the estimation of the DoA of a transmitter, the authors would also be interested in what is being transmitted, for example, a bit stream representing a communication signal source, a strategic command, and so on. In the time domain at each sensor, delays relative to the time of transmission are estimated through a cross-correlation between transmitted and received signals for different test locations of the transmitter. The true location is where the correlation is at the maximum. Theoretically, just one sensor is enough for localization when the transmitted signal is truly broadband. For a broadband signal, the authors work in the frequency domain.
