Directly lidar research
|School||University of Electronic Science and Technology|
|Keywords||Lidar Double Edge Technology Direct detection F - P etalon|
The direct wind lidar remote sensing tools to detect the fine structure of the clear sky wind farm , has important significance for weather forecasting , atmospheric dynamics , aviation wind shear safety warning and defense applications , and a significant application prospects . Laser Doppler wind measurement radar from the works can be divided into two kinds of coherent and incoherent ( direct detection ) . Paper uses a dual-channel Fabry-Perot (FP) interferometer direct detection system to detect the Mie scattering echo signal . Taking into account the role of atmospheric aerosols and molecular movement of the divergence of the laser beam , at low altitude , emitting laser with 1064nm , atmospheric molecules Rayleigh scattering echo signal is almost zero , aerosol Mie scattering signal is relatively strong , which gives the signal probing bring great convenience . Frequency discriminator system is one of the key technologies of the Doppler radar wind measurement from the probe light intensity change analysis of the frequency shift , and the ability to affect the frequency discriminator radar wind measurement precision . This paper analyzes the basic principle of the lidar . The direct detection method , the edge technology lock the frequency of laser light incident on the steep edge of the frequency discriminator , the smaller the frequency shift will result in a larger signal intensity changes . System the thesis research anemometers radar frequency discriminator , double edge for low-altitude aerosol scattering signal detection theory , and simulation FP laser beam transmittance function , select the most impact on the sensitivity of the system according to different parameters FP FP parameters , simulation frequency discriminator system suitable frequency discriminator process. Analysis of the laser linewidth , etalon surface quality system frequency discriminator , at this stage , we use FP dual channel is a separate independent channels , in order to improve its stability , improve the two etalon fixed in on one substrate , they are subject to environmental interference center frequency drift change same, can then ensure that the center of the spectrum of the etalon interval undisturbed . In order to ensure that the outgoing laser frequency at the center position of the double FP etalon , using a feedback signal modulator etalon transmittance cavity length . Finally , the simulation data analysis to select the appropriate parameters , given the wind speed error varies with height simulation results .