Adaptive waveform design in random stepped frequency radar

Random stepped frequency (RSF) radar, whose carrier frequencies randomly hop pulse by pulse, improves the range-Doppler ambiguity and produces excellent electronic counter-countermeasures (ECCM) ability. Sparse Recovery technique improves the sensing performance of RSF radar by exploiting the sparsity of the observed targets. In this paper, a cognitive mechanism is implemented to further enhance the RSF radar. The transmitted waveforms, i.e. frequency-hopping codes, are adaptively designed to coordinate with the targets. We choose to minimize the Cramer-Rao bound on sparse recovery errors as the waveform-design criterion, and devise two corresponding algorithms. Simulations are performed, whose results demonstrate that the proposed cognitive mechanism introduces significant improvements on the performance of targets recovery.