Ma Xin, Zhang Haowei, Han Ge, Xu Hao, Shi Tianqi, Gong Wei, Ma Yue, Li Song
State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan 473079, China.
CAS Key Laboratory of Spectral Imaging Technology, Xi'an 710119, China.
Sensors (Basel). 2020 Oct 17;20(20):5887. doi: 10.3390/s20205887.
For high-precision measurements of the CO column concentration in the atmosphere with airborne integrated path differential absorption (IPDA) Lidar, the exact distance of the Lidar beam to the scattering surface, that is, the length of the column, must be measured accurately. For the high-precision inversion of the column length, we propose a set of methods on the basis of the actual conditions, including autocorrelation detection, adaptive filtering, Gaussian decomposition, and optimized Levenberg-Marquardt fitting based on the generalized Gaussian distribution. Then, based on the information of a pair of laser pulses, we use the direct adjustment method of unequal precision to eliminate the error in the distance measurement. Further, the effect of atmospheric delay on distance measurements is considered, leading to further correction of the inversion results. At last, an airborne experiment was carried out in a sea area near Qinhuangdao, China on March 14, 2019. The results showed that the ranging accuracy can reach 0.9066 m, which achieved an excellent ranging accuracy on 1.57-μm IPDA Lidar and met the requirement for high-precision CO column length inversion.
对于利用机载积分路径差分吸收（IPDA）激光雷达对大气中一氧化碳柱浓度进行高精度测量而言，必须精确测量激光雷达光束到散射面的精确距离，即柱的长度。为了对柱长度进行高精度反演，我们根据实际情况提出了一套方法，包括自相关检测、自适应滤波、高斯分解以及基于广义高斯分布的优化列文伯格 - 马夸尔特拟合。然后，基于一对激光脉冲的信息，我们采用不等精度直接平差法消除距离测量中的误差。此外，考虑了大气延迟对距离测量的影响，从而对反演结果进行进一步校正。最后，于2019年3月14日在中国秦皇岛附近海域进行了一次机载实验。结果表明，测距精度可达0.9066米，在1.57 -μm IPDA激光雷达上实现了优异的测距精度，满足了高精度一氧化碳柱长度反演的要求。
