The Range Ambiguity Suppression Based On Amplitude Modulation Chirp

Range and azimuth ambiguities are contradictory in SAR system, which restrict the improvements of resolution and swath in satellite platform. Multichannel needs big and complex antenna. And it is proved that orthogonal transmitting signals cannot suppress range ambiguity. Thus high resolution and wide swath system is still a challenge in SAR development. In this paper, we design a novel range ambiguity suppressing method with single channel, which transmits amplitude modulation chirp signals. Through frequency filtering, the ambiguity images can be separated. A minimum mean square error algorithm is then proposed to restore the resolution robustly. Experiment based on Radatsat-1 echo shows that the proposed method can reduce the range ambiguity by 20 dB. Using this method, single-channel system can extend the swath width twice.