Finding sensor trajectories for TDOA based localization — Preliminary considerations

Time Difference of Arrival (TDOA) measurements are gained in a network of sensors where a minimum of two sensors is required. Sensors receive the signal of an emitting target and determine the Time of Arrival (TOA) of the signal. Calculating the difference between pairs of TOAs yields TDOA measurements which describe hyperbolae or hyperboloids as possible target locations. The Cramer Rao Lower bound (CRLB) gives the optimal attainable localization accuracy based on a measurement sequence. It depends on the measurement function which reflects the sensors-emitter geometry, the measurement error and the number of measurements. The CRLB can be used to find future trajectories for moving sensors. In this paper, a sensor pair consisting of a moving and a stationary sensor is investigated which takes TDOA measurements of a stationary emitting target. The future trajectory of the moving sensor is determined based on target localization performance.