Frequency stabilization method in direct detection Doppler wind lidar under field experiment conditions

Direct detection Doppler wind lidar based on Fabry-Perot etalon is an effective detection means of middle-upper atmospheric wind field. The long-term stabilization of system is basic requirement to perform a task. Firstly, the invalid detection data of DWL was analyzed, the relative drift of laser frequency was the main factor of invalid data. Then, the experiment was set up. To verify the mechanism of seed laser environment temperature changes and the environment temperature changes of locking etalon and the transmission of locking etalon, the result was obtained, which 1℃ temperature change of seed laser environment in Nd:YAG laser systems would cause the change of etalon transmission up to 46.1% and it was equivalent to 1.536 GHz frequency drift of laser, 1℃ temperature change of etalon environment would cause about 737.7 MHz relative drift of laser frequency. To ensure the precision less than 1 m/s resulted from system error, the method of three-step temperature control would be established. The operating room's temperature of DWL would be controlled with precision of 1℃ in the first, and then, the seed laser and the etalon would be placed in the constant temperature box with temperature control precision of 0.001℃, respectively, and the accuracy of wind field detection would be achieved.