减小声光频谱仪频率测量方差算法的研究.pdfVIP

第44卷第5期 红外与激光工程 2015年5月 Vol.44No.5 InfraredandLaserEngineering May2015 减小声光频谱仪频率测量方差算法研究 何其锐 袁李立萍1 2 (1. 电子科技大学光电信息学院袁四川 成都 610054曰 2. 电子科技大学 电子工程学院袁四川 成都 611731) 摘 要院声光器件衍射光峰值偏转位置与输入信号频率成正比是声光频谱仪测频的基本原理袁 但实 际中衍射的非线形效应会引起衍射光峰值偏转误差较大遥为减小频率测量方差袁需对衍射光强数据做 相应处理遥对CCD 背景噪声的数字特征分析袁以背景噪声数学平均值为阈值做去噪处理遥根据最小二 乘法原理袁对衍射光强数据做一次高斯函数拟合袁拟合数据与光强数据相关系数为0.997 6遥在现有测 试光学平台下袁根据衍射光强峰值位置估计的频率测量方差为542.5 kHz 袁利用拟合高斯函数中心值2 2 估计的频率测量方差为31.8 kHz 遥 为减小声光频谱仪频率测量方差提供了理论支持遥 关键词院测量方差曰 声光测频曰 高斯拟合法曰 最小二乘法 + 中图分类号院TP802 .2 文献标志码院A 文章编号院1007-2276(2015)05-1564-05 Algorithm studyonreducingfrequency measurement variance ofacousto-opticspectrumanalyzer He Qirui, Li Liping1 2 (1. School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054, China; 2. School of Electronic Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China) Abstract: Diffraction beam deflection peak position of the acousto-optic device is proportional to the input signal frequency. It is the basic theory for acousto-optic spectrum analyzer frequency measurement. But the non-linear effects in diffraction causes diffraction peak deflection error. To get better measurement results, the diffraction intensity data should be processed to reduce the frequency of measurement variance. After the digital features of CCD background noise were analyzed, the background noise mathematical average had been taken as the threshold w