Adaptive waveform design for interference mitigation in SAR

摘要

This work details an interference mitigation scheme for synthetic aperture radar (SAR) which adapts the transmitted waveform spectrum to restore the quality of the scene range-profile based on the estimated interference spectrum. By expressing the estimation of the range-profile in the presence of correlated noise as a system identification problem, a cost function for the optimal waveform is derived. In order to respond effectively to changes in the radio frequency (RF) environment, adaptive waveform systems should perform waveform design on a small timescale, ideally on a pulse-to-pulse basis. Motivated by the need for a computationally efficient waveform design scheme, an alternative estimator is derived, which yields a closed form solution, which is shown to perform similarly to the optimal case. A series of test SAR images demonstrate the efficacy of this technique and are compared to the standard linearly frequency modulated signal and stretch processing outcome.