Doppler laser radar wind measurement method and device

Abstract

The invention discloses a Doppler laser radar wind measurement method and device. The method comprises the steps that beam splitting and power amplification are performed on a first laser source and a second laser source and then coherent beam combining is performed on the first laser source and the second laser source under the synchronous phase-locked state by using an optical phase-locked loop feedback circuit module; the combined laser beams are transmitted to the atmosphere and then echo optical signals are collected; heterodyne beat detection is performed on the collected echo optical signals and the oscillating optical signals of the device; and wind speed inversion analysis is performed on the detected spectrum data. The frequency shift effect is realized by adjusting the frequency difference between the first and second laser sources, and the acousto-optic frequency shift device in the prior art is replaced so that the more abundant extension modes and the more flexible spectrum data analysis selection can be provided for the laser radar system.

Description

technical field [0001] The invention relates to the technical field of laser radar, in particular to a Doppler laser radar wind measurement method and device. Background technique [0002] Doppler wind lidar technology is a high-precision atmospheric wind field information telemetry technology. The laser radar system emits a high-spectrum-purity laser beam into the detection airspace, and the aerosol particles in the atmosphere interact elastically with the laser beam. After the backscattered echo optical signal is effectively received by the radar signal transceiver system, it passes through the high-sensitivity optical frequency heterodyne The detection technology can accurately invert the measured Doppler spectrum information to obtain wind field information such as wind speed and wind direction. This technology has been widely used in the fields of clean wind power energy development, meteorological science, wind shear warning in the airspace of civil aviation airports,...

AI Technical Summary

Problems solved by technology

It is generally required that the spectral linewidth of the seed laser is narrow (generally <10kHz), low phase noise, and good frequency stability. Currently, the high-performance seed lasers on the market are generally expensive and have low optical power. They are used as acousto-optic modulation devices for frequency shifters. And RF drive devices are also expensive, and the above devices account for a considerable proportion of the cost of the entire lidar light source

Moreover, once the selection of the acousto-optic frequency shifting device is determined (that is, the frequency shift is fixed), it cannot be changed in the later spectral data processing, and more detailed and flexible spectral data analysis cannot be performed.

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