Lyons B W, Robinson S R
Appl Opt. 1979 Mar 15;18(6):781-90. doi: 10.1364/AO.18.000781.
An imaging system that consists of a laser scanning a surface and a heterodyne receiver that measures the backscattered field is considered. The second moment statistics of the amplitude and amplitude-squared of the output signal of the optical receiver are developed, assuming the rough surface is a random process with known mean, variance, and correlation distance properties. The mean and covariance functions of each measurement are related to the scattered field correlation function, the reflection of the surface, and the key system parameters. The resulting noise models describe both the average speckle cell size and the contrast variations in the image caused by speckle noise.
考虑一种成像系统，它由扫描表面的激光和测量反向散射场的外差接收器组成。假设粗糙表面是一个具有已知均值、方差和相关距离特性的随机过程，推导了光接收器输出信号幅度和幅度平方的二阶矩统计量。每个测量的均值和协方差函数与散射场相关函数、表面反射以及关键系统参数有关。所得的噪声模型描述了平均散斑单元大小以及由散斑噪声引起的图像对比度变化。
