A decoupled algorithm for geolocation of multiple emitters

The problem of determining the positions of multiple emitters by widely separated arrays is considered. We propose an iterative algorithm for estimating the positions based on the maximum likelihood (ML) criterion. The position of each emitter is decoupled from the other emitters, and in each iteration is determined by a two dimensional grid search. This approach substantially reduces the computation load of a straightforward implementation of the ML estimator, which requires a multidimensional search. Numerical examples are provided to illustrate the performance. We demonstrate that only a few iterations are required to achieve convergence. The results are compared with the Cramér-Rao lower bound.