本振功率对目标微动激光平衡外差探测的影响的研究.pdfVIP

第44卷第10期 红外与激光工程 2015年10月 Vol.44No.10 InfraredandLaserEngineering Oct.2015 本振功率对目标微动激光平衡外差探测的影响研究 郭力仁，胡以华，李 政，徐世龙 (1. 脉冲功率激光技术国家重点实验室 电子工程学院，安徽 合肥 230037； 2. 电子制约技术安徽省重点实验室，安徽 合肥 230037) 摘 要院 面向远距离目标微多普勒效应的探测，建立了本振光功率变化对激光平衡外差探测回波信 噪比影响的数学模型，并进行了仿真分析。通过搭建的 1550nm激光平衡外差探测实验平台测试了 由于本振功率变化对于目标微多普勒特征提取效果的影响。研究结果表明，对于平衡外差探测，由于 两光电探测器量子效率不可能完全匹配，考虑到散粒噪声、热噪声和本振相对强度噪声的影响，将存 在一个最佳本振功率值使探测信噪比达到最大。当选取该本振功率进行探测时，获得的目标微多普 勒特征可读性更强，提取误差更小。 关键词院探测器； 微多普勒效应； 平衡外差探测； 本振功率； 激光雷达 中图分类号院TN95 文献标志码院A 文章编号院1007-2276(2015)10-2933-05 Influence of Local Oscillate power on micro鄄motion balanced heterodyne detection for Lidar Guo Liren, Hu Yihua, Li Zheng, Xu Shilong (1. State Key Laboratory of Pulsed Power Laser Technology, Electronic Engineering Institute, Hefei 230037, China; 2. Anhui Province Key Laboratory of Electronic Restriction Technology, Hefei 230037, China) Abstract: Aimming at detecting the micro鄄Doppler effect of target away, the mathetical model of variational Local Oscillate (LO) power influence to signal to noise ratio (SNR) of balanced heterodyne detection for coherent lidar were established. Besides, simulation analysis on this model was proceeded. The effect on feature extraction was observed through experiments. The results show that in balanced heterodyne detection, where quantum efficiency of two photo electric detectors can忆t match completely in reality, there will be a specific LO power making the SNR best, considering the shot noise,hot noise and LO intensity noise. While choosing the optimal LO power in detection, the micro鄄doppler feature extracted will be more readable and accurate.