Performance validation and error analysis for a direct detection molecular Doppler lidar

摘要

In this paper we present a detailed analysis of the performance of the Goddard Lidar Observatory for Winds (GLOW) Doppler lidar. GLOW is a mobile direct detection Doppler lidar system which uses the double edge technique to measure the Doppler shift of the molecular backscattered laser signal at a wavelength of 355 nm. The lidar has been used in several recent field experiments to measure wind profiles from the surface into the lower stratosphere. Simulations of detected signal levels predicted using a realistic instrument model and representative atmospheric model will be presented and compared with range resolved signals detected with the photon counting data acquisition system. A detailed analysis of wind errors observed with the system will also be reported. The analysis begins by propagating ideal shot noise limited errors through the analysis algorithms used to calculate winds. The resulting shot noise limited errors are compared with statistical standard deviations obtained by averaging multiple independent wind profiles taken at various temporal and spatial sampling scales. An assessment of other instrumental and atmospheric effects contributing to the wind error will also be given.