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For direct detection Mie Doppler wind lidar, the method of use Fabry-Perot interferometer as a dynamic Doppler shift discriminator is proposed and investigated theoretically. For the highest measuring sensitivity part of the FPI transmission curves is utilized to measure any possible laser Doppler shift, its measuring accuracy is very high. With no loss of this significant superiority, any actual wind speed range requirement can be met by repeating this way in a measurement. The simulations for different atmosphere conditions prove that this method is more suitable for wind measurement of higher part troposphere than previous.

Simple lidar detecting wake profiles based on laser backscattering by wake bubbles at 180° is firstly introduced. Then the various noises of this simple lidar, including the background light, power frequency of 50Hz and its harmonics, radio frequency noise and inherent noise within the electronic system, are analyzed in detailed, and the relationship of the minimum detectable signal power and the echo signal power is discussed. Finally, under the condition of satisfying the noise level, the data processing method of wake profiles is given. For this method, the power spectral density estimation method is used to process the bubble laser scattering signal and cubic spline interpolation is used to obtain contour map of wake profile. The results show that the data processing method of wake profiles meets the noise level and the obtained contour map is reasonable.