Superresolution techniques in time of arrival estimation for precise geolocation

There is an increasing need for methods to precisely localize fixed emitters in a complex multipath environment. We consider a ground-based distributed network of nodes, each having a sensor array, and focus on the problem of emitter geolocation when array calibration is either unreliable or unavailable. We first develop a technique applicable when array calibration information is available and analyze its sensitivity to calibration errors. We then present a new superresolution array-based time-of-arrival technique applicable when calibration information is unavailable, and develop the associated Cramer-Rao bounds. Performance results are shown with computer-simulated data and real data from the DARPA-sponsored novel antenna program (NAP).