The wind field data are important input parameters for the stratospheric airship in the long-time loiter and the flight control. In view of the thin air in the stratosphere and the low precision of the pitot tube, a direct detection method based on LIDAR is proposed. A Doppler lidar velocity measurement system based on the direct detection principle is designed. The wind velocity inversion mathematical model of the two fringe imaging techniques is built and numerical simulations are carried out. It is shown that the measurement errors of the Fabry-Perot etalon (FPI) and the Mach-Zehnder interferometer (MZI) are 11.0% and 6.5%, respectively, at 355 nm output laser and 20 m/s wind speed. And the velocity resolution of the two methods are 1.9 m/s and 1.6 m/s, respectively. The results indicate that the new method can effectively meet the requirements of the stratospheric airship wind speed measurement.

stratospheric airship  /  wind measurement  /  lidar  /  fringe imaging technique