Range Ambiguity Suppression Based on Two-dimensional Phase Coding
LI Jian SUN Guangcai JING Guobin XING Mengdao
(National Key Laboratory of Radar Signal Processing, Xidian University, Xi'an 710071, China)
(Collaborative Innovation Center of Information Sensing and Understanding, Xidian University, Xi'an 710071, China)
Abstract:Based on a two-dimensional phase coding, a novel range ambiguity suppression method is proposed. By transmitting two-dimensional phase coded signals and demodulating the received signals, the two-dimensional spectrum of the range ambiguity is shifted along both range and azimuth directions. Considering the range frequency and Doppler oversampling, the spectrum of the range ambiguity located outside the data region of spectral support can be filtered out, which suppresses the range ambiguity. It allows for decreasing of the Range Ambiguity to Signal Ratio (RASR) and upgrading of the SAR image quality. Simulation results for point targets and distributed targets validate the effectiveness of the proposed method.
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