基于二维查找表结构的SAR原始数据自适应频域压缩算法

该文针对实际SAR多普勒中心偏移及多普勒谱分裂问题,提出基于一维查找表的自适应多普勒非均匀压缩比分配方法,该方法结合一维量化编码查找表构成二维查找表结构的SAR原始数据自适应频域压缩算法.该文推导了SAR距离向回波频谱解析式,给出距离向非均匀压缩比分配通用方案.实际数据处理结果表明,该方法比传统频域类压缩算法具有更好的信噪比及鲁棒性.理论分析结果表明,其运算量提高很小,易于工程实现.

Adaptive Frequency Domain Algorithm for SAR Raw Data Compression Based on Two Dimensions Look-up Table

According to Doppler centroid shift and Doppler spectrum split, this paper proposes an adaptive Doppler nonuniform bit allocation approach based on one dimension Look-Up Table (LUT). Combined with one dimension quantization and coding LUT this approach forms the adaptive compression algorithm in frequency domain. Meanwhile, this paper deduces the spectrum analytic function of the echo in range and provides with the general scheme for nonuniform compression ratio allocation. Numerical experiments results based on real SAR data show that new algorithm has higher SNR and better robustness than traditional frequency domain algorithms. Theoretical analysis shows that the calculation load is small and can be easily applied in engineering.