Laser & Optoelectronics Progress, Volume. 55, Issue 12, 120005(2018)
Application Progress of Time-Frequency Analysis for Lidar
Fig. 1. Simulation results of tail vortex and Wigner-Ville distribution of radial velocity profiles. (a) Numerical simulation diagram of contour plot of tail vortex pair; (b) three radial velocity profiles of line of slight; (c) average Wigner-Ville distribution of black solid lines in fig. (b)
Fig. 2. Spectral images of wind speed varying with distance. (a) 1.5 μm all-fiber single frequency lidar; (b) long-distance Doppler lidar
Fig. 3. Reconstruction results of 2D wavelet. (a) Original relative temperature perturbations from July 16 to 18, 2014; (b) reconstruction period of 3.6 h; (c) reconstruction period of 4.8 h; (d) reconstruction period of 7.8 h; (e) the temperature perturbation field reconstructed from combining the above three major wave packets
Fig. 4. Gravity wave perturbations (a)-(c) and distribution function of spectral energy (d)-(f). (a) Initial temperature perturbations; (b) waves with upward phase progression; (c) waves with downward phase progression; (d) Vertical wavelength versus phase velocity; (e) vertical wavelength versus period; (f) altitude versus vertical wavelength
Fig. 5. Comparison of wind shear distribution between simulation results and actual measurements. (a) Simulation results; (b) actual measurements
Fig. 6. Comparison diagrams of inversion results. (a) Original and denoised data; (b) denoised data and average of 1000 sets of accumulative signals
Fig. 8. Comparison of the spectrogram results. (a) Spectrogram and oscillogram of an original LDV signal; (b) spectrogram and oscillogram of a Wiener filtered signal; (c) spectrogram and oscillogram of a clean signal
Fig. 9. THI displays of water-vapor mixing ratio recorded from 2016-09-22T00:00 to 2016-09-23T00:00 before and after denosing. (a) Before denoising; (b) after denoising
Fig. 10. Spectrograms of the received signals from the targets at 250 m. (a) Stationary target; (b) moving target
Fig. 11. Test results of Gabor wavelet transform. (a) Tile 1 original data; (b) Tile 1 segmented result; (c) Tile 2 original data; (d) Tile 2 segmented result
Fig. 12. Comparison of segmented trees and buildings using matching pursuit method. (a) Trees; (b) buildings; (c) tree area detected by an 11×11 window; (d) building area detected by an 11×11 window; (e) tree area detected by a 7×7 window; (f) building area detected by a 7×7 window
Fig. 13. Spectrogram results. (a) Normalized spectrogram of the target speed versus time with tone spacing of 10 GHz; (b) velocity spectrogram after hard threshold processing
Fig. 14. Airplane model and imaging results based on two methods. (a) Optical photo of the airplane model made of stone; (b) image result based on the FFT(fast Fourier transformation) method; (c) azimuth multilook result based on the FFT method; (d) azimuth multilook result based on the JTFT method
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Yanping Liu, Chong Wang, Haiyun Xia. Application Progress of Time-Frequency Analysis for Lidar[J]. Laser & Optoelectronics Progress, 2018, 55(12): 120005
Category: Reviews
Received: May. 1, 2018
Accepted: Jul. 5, 2018
Published Online: Aug. 1, 2019
The Author Email: Yanping Liu (yanping@mail.ustc.edu.cn), Chong Wang (wcltr@163.com), Haiyun Xia (hsia@ustc.edu.cn)