Modeling the Heterodyne Efficiency of Array Detector Systems in the Presence of Target Speckle

To solve the speckle effect problem in heterodyne detection, an array detector is proposed; heterodyne efficiency is modeled by accounting for speckle and using an additional parameter to simulate coherent summation processing. Heterodyne efficiency is derived by mixing a Monte Carlo simulated speckle field with a planar local oscillator field on a photodetector surface to evaluate the array detector performance at improving signal-to-noise ratio (SNR) of the coherent optical system. From the simulation results, the array detector is shown to effectively improve the SNR of the heterodyne system. For low SNR, the heterodyne efficiency of an
N
 × 
N
array detector increases linearly with
N
.