强度相干成像中符合计数方法的优化与仿真

为提高强度相干成像中符合计数方法的探测信噪比,实现对中高轨卫星的清晰成像。根据HBT效应和光电转换半经典模型建立了强度相干的符合计数简化模型,分析了设备时间测量误差、符合窗函数和观测光谱形状对符合计数探测信噪比的影响,并根据观测条件对符合窗函数进行了优化。利用蒙特卡洛方法仿真了符合窗函数对探测信噪比的影响。仿真结果表明:利用最优符合窗测量目标的频谱模值时,其探测信噪比较传统方法提高了39.2倍。通过对符合窗的优化能够有效提高强度相干成像探测信噪比,提高对暗弱目标的强度相干成像质量。

Amelioration and simulation of coincidence counting towards intensity correlation imaging

The research aims to offer a solution to raise the detecting SNR of coincidence counting in intensity correlation imaging method and to obtain a clear image of high-orbit satellite. A simplified model of coincidence counting in intensity correlation was built based on the Hanbury Brown Twiss Effect and the photoelectric conversion semi-classical model. As well as the influence on the detecting SNR of coincidence counting caused by the time measurement error of detection equipment, the effect of coincidence window and the observed spectral shape was analyzed. Furthermore, an optimization on window function according to these observing conditions was offered. Finally, the coincidence window's effects on detecting SNR with the Monte-Carlo method were simulated. The simulation result shows that, by practicing the process of optimized coincidence window in intensity correlation imaging, the detecting SNR increases 39.2 times more than that with traditional method. The detecting SNR and the image quality of dim target can be efficiently improved as well by the window optimization.