基于失真度量的SAR原始回波饱和抑制方法

Distortion-degree Based Saturation Suppression Method for SAR Raw Data

在合成孔径雷达系统中,针对块自适应量化压缩算法处理饱和数据引起的性能下降,现有方法通常从解码端对信号进行功率补偿,但并未从根本上解决原始数据饱和问题。文中首先研究了部分饱和高斯回波信号的统计分布,推导出常用AD量化准则下任意比特AD回波数据的标准差估计方法。随后通过该方法,引入信号失真度,并提出了一种基于失真度量的饱和抑制方法。仿真结果表明,文中提出的方法可在保证良好动态范围的同时有效降低信号失真度,当原始信号严重饱和时,可使失真度降低1~2个数量级。

In the synthetic aperture radar system,to deal with the performance degradation problem of the block adaptive quantization algorithm due to signal saturation,current methods usually compensate the signal power at the receiver side,which however does not fundamentally solve the signal saturation problem.This paper first investigated the statistical distribution of the partially saturated Gaussian echo signal,and summarized a standard deviation estimation method for arbitrary-bit sampled echo data under common quantization criteria.Through introducing the concept of distortion degree,we proposed a distortion-degree based saturation suppression method.Simulation results showed that the proposed saturation suppression method could significantly decrease the signal distortion degree.When the signal is heavily saturated,the distortion degree can be decreased by 1~2 orders of magnitude.