Airship-Borne Rayleigh Doppler Wind LiDAR and Its Motion Compensation Algorithm

To address the wind measurement requirements for stratospheric airships, an airship-borne Rayleigh Doppler wind lidar is proposed. The system employs a 532 nm pulsed laser source and detects the echo frequency shift using iodine molecular absorption filter, then retrieves the wind field based on the Doppler principle. To mitigate the influence of airship platform motion on wind measurements, a motion compensation algorithm is developed, utilizing an integrated inertial navigation system. The algorithm establishes the relationship between wind speed and frequency shift through coordinate system transformation. To handle the spectral broadening caused by thermal motion echoes, it innovatively transforms the wind speed calculation problem into a parameter estimation problem involving multiple samples and distributions, solving it by using the maximum likelihood method. Simulation results demonstrate that the proposed algorithm effectively corrects wind measurement errors induced by platform motion. When observing the wind field at an altitude of 21 km with a 45° elevation angle from 18 km altitude, the wind speed measurement accuracy is approximately 1 m/s, and the wind direction measurement accuracy is about 2.5°, showing potential for practical applicationin wind measurement for stratospheric airships.