Adaptive Frequency Domain Algorithm for SAR Raw Data Compression Based on Two Dimensional Look-Up Table

摘要

According to Doppler centroid shift and Doppler spectrum split, this paper proposes an adaptive Doppler NonuniformrnBit Allocation (NBA) approach based on one dimensional Look-Up Table (LUT). Combined with onerndimensional quantization and coding LUT, NBA approach forms the adaptive compression algorithm in frequencyrndomain. Meanwhile, this paper deduces the analytic function of the frequency spectrum of the echoes inrnrange and provides with the general scheme for its NBA. Numerical experiments results based on real SAR datarnshow that new algorithm has higher SNR and better robustness than FFT-BAQ. Theoretical analysis indicatesrnthat the calculation load of new algorithm is small so it can be easily applied in engineering.