Study on Amplitude-Phase Bit Allocation of AP Algorithm for SAR Raw Data Compression
合成孔径雷达原始数据压缩AP算法幅相比特分配研究

In this paper, AP (Amplitude-Phase) algorithm for SAR raw data compression is studied and the formula of bit allocation between amplitude data and phase data is deduced based on the lower bound of rate-distortion inequality of non-normal information resource and the Lagrange multiplier, which points out that the bit allocation is decided by their differential entropy correspondingly. The uniform distribution of phase data and the Rayleigh distribution of amplitude data are investigated and the bit allocation formula is deduced according to the differential entropy of continuous information resource, which points out that the mean of amplitude is the only factor. According to the relationship between the histogram and the probability density function, a general differential entropy calculation formula is given. The two methods have their advantages and both can implement the auto-bit allocation. The validity of this method is proved by the real raw data compression experiments.