CAJ | 학술논문

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1 550 nm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.
면향원거리목표미다보륵효응적탐측,건립료본진광공솔변화대격광평형외차탐측회파신조비영향적수학모형,병진행료방진분석.통과탑건적1 550 nm격광평형외차탐측실험평태측시료유우본진공솔변화대우목표미다보륵특정제취효과적영향.연구결과표명,대우평형외차탐측,유우량광전탐측기양자효솔불가능완전필배,고필도산립조성、열조성화본진상대강도조성적영향,장존재일개최가본진공솔치사탐측신조비체도최대.당선취해본진공솔진행탐측시,획득적목표미다보륵특정가독성경강,제취오차경소.
Aimming at detecting the micro-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'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-doppler feature extracted will be more readable and accurate.