Comparison of simultaneous signals obtained from a dual-field-of-view lidar and its application to noise reduction based on empirical mode decomposition  

作　　者：龚威 李俊 毛飞跃 张金业 

机构地区：[1]State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University [2]School of Science,Hubei University of Technology

出　　处：《Chinese Optics Letters》2011年第5期1-4,共4页中国光学快报（英文版）

基　　金：supported by the National "973" Program of China (Nos. 2009CB723905 and 2011CB707106);the National Natural Science Foundation of China(Nos. 10978003 and 40871171)

摘　　要：Although the empirical mode decomposition （EMD） method is an effective tool for noise reduction in lidar signals, evaluating the effectiveness of the denoising method is difficult. A dual-field-of-view lidar for observing atmospheric aerosols is described. The backscattering signals obtained from two channels have different signal-to-noise ratios （SNRs）. The performance of noise reduction can be investigated by comparing the high SNR signal and the denoised low SNR signal without a simulation experiment. With this approach, the signal and noise are extracted to one intrinsic mode function （IMF） by the EMD- based denoising; thus, the threshold method is applied to the IMFs. Experimental results show that the improved threshold method can effectively perform noise reduction while preserving useful sudden-change information.Although the empirical mode decomposition （EMD） method is an effective tool for noise reduction in lidar signals, evaluating the effectiveness of the denoising method is difficult. A dual-field-of-view lidar for observing atmospheric aerosols is described. The backscattering signals obtained from two channels have different signal-to-noise ratios （SNRs）. The performance of noise reduction can be investigated by comparing the high SNR signal and the denoised low SNR signal without a simulation experiment. With this approach, the signal and noise are extracted to one intrinsic mode function （IMF） by the EMD- based denoising; thus, the threshold method is applied to the IMFs. Experimental results show that the improved threshold method can effectively perform noise reduction while preserving useful sudden-change information.

关 键 词：Atmospheric aerosols Noise pollution control Optical radar Signal processing Signal to noise ratio 

分 类 号：TN958.98[电子电信—信号与信息处理] TN911.7[电子电信—信息与通信工程]