基于菲佐干涉仪与多通道光电倍增管阵列的多普勒频移检测技术

提出了基于菲佐干涉仪和多通道光电倍增管(PMT)阵列探测器组合的多普勒频移检测的方案, 适用于风速测量的直接探测多普勒激光雷达。首先介绍了工作原理, 再根据菲佐干涉仪光谱特征对频移检测用干涉仪进行了优化设计, 优化设计的菲佐干涉仪腔长150mm、平板反射率0.755。对提出的菲佐干涉仪和多通道光电倍增管阵列探测器组合的方案进行了数值模拟, 以分子散射作为背景噪声, 计算了该方法的风速测量误差。模拟结果表明, 设计的基于菲佐干涉仪的直接探测多普勒测风激光雷达, 在30 s的积分时间内、探测高度5 km以下,

A method of discriminating Doppler shift using Fizeau interferometer and linear PMT array for a direct-detection wind Doppler lidar is proposed. At first, its working principle is introduced. According to the spectral character of Fizeau interferometer, optimum design of frequency shift discrimination interferometer is presented, and the designed Fizeau interferometer has the cavity length of 150 mm and reflectivity of 0.755 from plate. The numerical simulation for wind speed measurement using the Fizeau interferometer and PMT array detector is also presented. The effect of molecular backscattering taken as background noise is analyzed. The error of wind speed measurement using system with Fizeau interferometer and linear PMT array is calculated. The results show that wind velocity error can be less than 0.56 m/s in the 5 km range under 30 s average time using the proposed system.