Robust molecular wind lidar with Quadri Mach-Zehnder interferometer and UV fiber laser for calibration/validation and future generation of Aeolus

Abstract

Wind speed measurement with on-board system has many applications in aeronautics (Gust Load alleviation, Haps, etc.) and space (Weather forecast). The molecular wind lidar is developed for those purposes as it sent laser pulses into the atmosphere to determine, with a spectral analyzer, the wind speed from the Doppler shift induced by the molecules of the atmosphere. In this paper we present the lidar architecture developed at ONERA, that uses a Quadri Mach-Zehnder (QMZ) as a spectral analyzer and a UV fiber laser, designed for gust load alleviation application. We discuss about the advantages of such architecture for wind measurement from space. Simulations of the performances have been performed in the case of Calibration/Validation (Cal/Val) of Aeolus, showing standard deviation on wind speed measurement less than 2 m/s up to 17 km of altitude for the optimized hybrid fiber laser of 10 W laser average power and a pulse repetition frequency (PRF) of 5 kHz. Simulations that evaluates the performances for Aeolus measurement with minor changes in the lidar architecture have been computed, with results showing that requirements are fulfilled up to 22.5 km of altitude with the optimized hybrid fiber laser of 10 W and 3 kHz PRF.