Experimental Evaluation of Adaptive Doppler Estimation for PRI-Staggered Radar

Doppler processing enables pulse-Doppler radar to cancel clutter and discriminate movers based on their relative radial motion by exploiting slow-time signal coherence across the pulses of a radar dwell. Where the unambiguous Doppler interval is bounded by half the pulse repetition frequency (PRF) when the set of pulse repetition intervals (PRIs) are uniform, the use of staggered PRIs is known to expand this interval according to the least common multiple of the various PRFs involved. Of course, doing so also alters the periodic-sinc Doppler response into structures that may possess disadvantageously high sidelobes, particularly when the PRIs are randomized, and this condition cannot be readily addressed through tapering like in the uniform case. Consequently, we examine application of the reiterative super-resolution (RISR) robust beamforming approach to this spectral estimation problem, demonstrating its utility using open-air measurements in conjunction with clutter cancellation.