Direct Position Determination for Single Sensor Emitter Localization with Unknown Period

In this paper, a novel direct position determination approach is proposed for single sensor emitter localization with unknown period. Based on signal periodicity, stationary emitters can be located by a single moving sensor with only one antenna. By exploiting the time difference of arrival between received signals at different trajectory points, the location of a non-cooperative emitter can be jointly estimated with its signal period. Since the time difference of arrival should be estimated before localization, this method, which is also known as two-step method, has poor performance at low signal-to-noise ratio. By grouping the conjugate products of signals received at different trajectory points, the well-known direct position determination method is extended to the field of single sensor emitter geolocation. The proposed method estimates the emitter position directly from the received signal, which reduces the information loss from time difference of arrival estimation to position estimation. Numerical simulations indicate that, compared with the conventional two-step method, the proposed method achieves better performance under low signal-to-noise ratio.