Online optimization of sensor trajectories for localization using TDOA measurements

Time Difference of Arrival (TDOA) uses the difference in arrival time of a signal at a minimum of two sensors to localize an emitter. In the case of only two sensors it is necessary for at least one sensor to move, otherwise the emitter can only be localized to a region around an infinite hyperbola. This paper proposes a method for optimizing sensor trajectories, based on the Cramér Rao Lower Bound (CRLB), such that rapid and accurate localization of the emitter is performed. The optimization must be performed online as the localization accuracy is strongly dependent on the geometry between the sensors and the emitter, and the emitter location is originally unknown. Simulated scenarios demonstrate that the online optimization enables a superior localization accuracy to be achieved, or a specified localization accuracy can be achieved in a shorter time.