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

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