合成孔径雷达原始数据压缩AP算法幅相比特分配研究

该文研究合成孔径雷达原始数据压缩AP算法，由非正态信源率失真不等式下界结合拉格朗日乘子法推导了幅相比特分配的微分熵公式，指出幅度微分熵和相位微分熵决定了幅相比特分配。进一步研究了相位的均匀分布特性和幅度的瑞利分布特性，由连续信源微分熵定义推导了幅相比特分配的幅度均值公式，指出幅度均值是决定幅相比特分配的唯一因素。根据统计直方图和概率密度之间的关系，给出了更为一般情况下的幅度相位微分熵计算公式。两种幅相比特分配方案各有优点，都可以实现幅度相位比特的自动分配。真实数据实验证实了该方法的有效性。

Study on Amplitude-Phase Bit Allocation of AP Algorithm for SAR Raw Data Compression

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.