Linear‐FM random radar waveform compressed by dechirping method

Abstract

This research proposes a novel linear frequency modulation (Linear-FM) random radar waveform and introduces a dechirping compression method. The proposed linear-FM random waveforms possess a thumbtack ambiguity function and low cross-correlation properties which are good for fighting against digital radio frequency memory repeat jammer similar to random noise waveforms. The dechirping compression method for the proposed linear-FM random radar waveform works by mixing the random radar echo signal with a local reference linear frequency modulated (LFM) signal to reduce the echo bandwidth and thus allows to use low-speed analogue-to-digital converter similar to the dechirping method for LFM waveform compression. Both numerical simulation and high-resolution circular synthetic aperture radar imaging experiment are conducted to demonstrate the good performance of the proposed waveform and the proposed dechirping compression method.