Optimal angular sensor separation for AOA localization

This paper establishes the angular separation requirements for angle-of-arrival (AOA) sensors in order to achieve the best mean squared error (MSE) localization performance for arbitrary but fixed sensor ranges. Optimal sensor placement for localization arises in several practical applications such as trajectory optimization for moving sensor platforms, e.g., unmanned aerial vehicles (UAVs). In optimal UAV path planning the angular separation between UAVs is an important parameter that has a significant impact on fuel efficiency and inter-UAV distance constraints. The paper shows that optimal angular sensor separation is in general not unique, and that when all sensors are equidistant from the emitter, there may exist optimal sensor configurations with non-uniform angular sensor separation in addition to equiangular separation. The results of the paper are illustrated with extensive simulation studies.