Optimised solution for hybrid TDOA/AOA-based geolocation using Nelder-Mead simplex method

A hybrid geolocation model that combines advantages of time difference of arrival (TDOA) and angle of arrival (AOA) techniques is widely used to determine a mobile location. However, measurement noise in TDOA and AOA data restricts the estimation accuracy of a mobile location. Based on general geolocation equation using TDOA and AOA measurements, the authors derived a total noise-enhanced localisation (TNEL) model here. Unlike the general geolocation equation, the proposed TNEL model overcomes the accuracy limit even when geolocation equation contains environmental error. Moreover, the objective function and constraint derived from TNEL model can yield optimal solution that is closer to the real location of an emitter. In order to increase localisation measurement accuracy, the authors applied Nelder-Mead (NM) simplex algorithm-based optimisation technique to minimise the estimation error of the TNEL model. Simulation results confirmed the performance of authors' proposed geolocation method.