An Emitter Localization Method Based on Multiple Differential Doppler Measurements

The localization of radio frequency (RF) emitting sources is a significant topic in civil and military applications, including communications and radar systems. The most notorious methods used for RF emitter localization are based on angle of arrival (AOA), time difference of arrival (TDOA), received signal strength (RSS), as well as hybrid methods. Nevertheless, differential Doppler measurements can be used to locate emitters using a technique known as frequency difference of arrival (FDOA). The choice of an FDOA-based method must take into account the characteristics of the scenario of interest, including sensor limitations and system response time. This work presents fundamental concepts about FDOA and details the geometrical method based on polar coordinates. It also presents an "on-the-fly" approach to estimate an emitter location based on multiple FDOA measurements. Simulations were carried out in two scenarios: acoustic and electromagnetic. In the electromagnetic scenario, the performance of the proposed method was also compared to the maximum likelihood estimator.