Suppressing azimuth ambiguity in spaceborne SAR images based on compressed sensing
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Abstract
In spaceborne synthetic aperture radar, undersampling at the rate of the pulse repetition frequency causes azimuth ambiguity, which induces ghost into the images. This paper introduces compressed sensing for azimuth ambiguity suppression and presents two novel methods from the perspectives of system design and image formation, known as azimuth random sampling and ambiguity separation, respectively. The first method makes the imaging results for the ambiguity zones as disperse as possible while ensuring that the imaging results for the main scene are affected as little as possible. The second method separates the ambiguity signals from the echoes and achieves imaging results without the ambiguity effect. Simulation results show that the two methods can reduce the ambiguity levels by about 16 dB and 99.37%, respectively.
Keywords
synthetic aperture radar compressed sensing azimuth ambiguity orthogonal matching pursuitPreview
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