A closed-form pseudolinear estimator for geolocation of scanning emitters

A closed-form solution for scanning emitter localization has been available for the case of three sensors. For more than three sensors the traditional approach is to employ the maximum likelihood estimator, which is a nonlinear estimator with no closed-form solution. This paper develops a new closed-form pseudolinear estimator for passive localization of scanning emitters for four or more sensors. The proposed estimator achieves localization performance on par with the maximum likelihood estimator at a much reduced complexity and free from stability problems that plague iterative numerical methods for finding the maximum likelihood estimate. The new estimator is based on a modification of the pseudolinear estimator for bearings-only localization. The superior performance of the developed estimator is illustrated with numerical examples.