差分吸收相干激光雷达中偏振分集技术研究

发布时间：2018-05-17 00:23

本文选题：偏振分集技术(PDT) + 平衡探测　；参考：《光电子·激光》2015年03期

【摘要】：为减小差分吸收相干激光雷达(DIAL)中偏振衰落对回波信号功率反演精度影响,研究了偏振分集技术(PDT)在相干DIAL中的作用,构建了利用STM32控制的双光束切换DIAL实验装置。依托构建的装置,利用平衡探测,分别采用PDT和一般外差探测完成多组次实验,应用单频检测方法得到20m光程下吸收气体不同浓度下相干中频信号的振幅值,并由此求解出on光和off光回波信号功率。对回波信号功率值差分信息与由HITRAN得到的参考差分信息比较发现:应用PDT能使探测分辨率提高4倍,对应到2km距离内,可以探测到3.5×10-6ppm的CO2浓度变化,满足了气候研究所需的优于1%的精度要求,验证了PDT消除偏振衰落以及提高相干DIAL分辨精度的作用。
[Abstract]:In order to reduce the effect of polarization fading on the power inversion accuracy of echo signal in differential absorption coherent lidar (Dial), the effect of polarization diversity technique on coherent DIAL is studied. A double beam switching DIAL experimental device controlled by STM32 is constructed. Based on the device, using balanced detection, using PDT and general heterodyne detection, the amplitude of coherent intermediate frequency signal at 20 m optical path under different concentration of absorbed gas is obtained by using single frequency detection method. The power of on light and off optical echo signal is calculated. Comparing the difference information of echo power value with the reference differential information obtained from HITRAN, it is found that the detection resolution can be increased by 4 times by using PDT, corresponding to the range of 2km, the change of CO2 concentration of 3.5 脳 10-6ppm can be detected. It meets the requirement of accuracy of 1% for climate research and verifies the effect of PDT to eliminate polarization fading and improve the resolution accuracy of coherent DIAL.
【作者单位】：合肥电子工程学院脉冲功率激光技术国家重点实验室电子制约技术安徽省重点实验室;
【基金】：国家自然科学基金(61271353) 安徽省自然科学基金(1308085QF123) 脉冲功率激光技术国家重点实验室主任基金资助项目
【分类号】：TN958.98

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