基于分段边缘拟合的测风多普勒差分干涉仪成像热漂移监测方法  

Thermal imaging drift monitoring of Doppler asymmetric spatial heterodyne spectroscopy for wind measurement based on segmented edge fitting

作　　者：张亚飞 冯玉涛[1] 傅頔 畅晨光 李娟[1] 白清兰[1] 胡炳樑[1] Zhang Ya-Fei;Feng Yu-Tao;Fu Di;Chang Chen-Guang;Li Juan;Bai Qing-Lan;Hu Bing-Liang(Key Laboratory of Spectral Imaging Technology,Xi’an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi’an 710119,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院西安光学精密机械研究所,光谱成像技术重点实验室,西安710119 [2]中国科学院大学,北京100049

出　　处：《物理学报》2022年第8期114-123,共10页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:41005019);中国科学院西部青年学者项目(批准号:XAB 2016A07)中国科学院西部之光交叉团队项目(批准号:E1294301)资助的课题;陕西省自然科学基础研究计划(批准号:2019JQ-931)~~。

摘　　要：多普勒差分干涉仪是近年来发展起来的一种适用于中高层大气风场星载测量的干涉仪,它依靠对干涉图相位的精确反演计算气辉谱线的多普勒频移得到大气风速.环境温度的变化导致干涉仪光机组件发生热变形,造成成像面在干涉方向上的热漂移,改变相位的像元分布,直接引入相位误差从而影响风速反演.为了减小这种成像热漂移对多普勒差分干涉仪相位反演的影响,本文用分段拟合的方法检测光栅的标尺刻槽在干涉图中成像图案的边缘,定位刻槽图案的亚像元位置并依此监测成像热漂移.在近红外多普勒差分干涉仪样机的热稳定实验中,像面热漂移检测结果与环境温度在高频振荡变化趋势上表现出较高一致性,二者相关系数经去基线后可达0.86,而干涉图相位漂移经成像热漂移校正后其高频振荡也得到大幅抑制,证明了该算法的有效性.为了进一步验证该算法精度,计算了数据信噪比以及拟合所用各项数据分布特征参数误差对边缘检测的影响,结果表明,边缘检测精度主要受数据信噪比和条纹频率参数准确性的制约,当拟合用条纹频率参数误差小于0.5%而其他数据分布特征参数误差在1%以内,数据信噪比在约35倍以上时,本文算法可以实现高于0.05像元的检测精度.Doppler asymmetric spatial heterodyne spectroscopy is recently developed for spaceborne measurement of middle and upper atmospheric wind field,which relies on the accurate inverse of interferogram phase to calculate the Doppler shift of airglow emission lines.The change of temperature leads the optical and mechanical components to thermally deformed,causing the imaging plane to thermally drift relative to the detector,changing the distribution of interferogram phase on pixels,and directly introducing phase errors to affect the wind speed inversion.In order to reduce the influence of imaging thermal drift on phase inversion,the segmented fitting method is used in this paper to detect the sub-pixel edges of notch patterns and monitor imaging thermal drift accordingly.In the thermal stability test of a near-infrared Doppler asymmetric spatial heterodyne interferometer prototype,the thermal imaging drifts and ambient temperature show a high consistency in the trend of high-frequency oscillation,and the correlation coefficient can reach 0.86 after removing the baseline.After phase correct by using the thermal imaging shift,the high-frequency oscillation of interferogram phase shift is also greatly suppressed.In order to further verify the accuracy of the algorithm,the influence of the data signal-to-noise ratio and the data distribution characteristic parameter errors used in the fitting on the edge detection are simulated.The results show that the edge detection accuracy is restricted mainly by the data signal-to-noise ratio and the accuracy of the fringe frequency parameters.When the error of the fringe frequency parameter used for fitting is less than 0.5%,the error of other data distribution characteristic parameters is less than 5%,and the data signal-to-noise ratio is enhanced more than 35 times,the algorithm in this paper can achieve a detection accuracy higher than 0.05 pixels.

关 键 词：大气风场测量 多普勒差分干涉仪 干涉成像 像面漂移 

分 类 号：TH744.3[机械工程—光学工程]