Development and Operational Analysis of an All-Fiber Coherent Doppler Lidar System for Wind Sensing and Aerosol Profiling

摘要

A 1.5- all-fiber coherent Doppler lidar system for wind sensing was developed and characterized. The system design and implementation is presented. The system employs a 20-kHz pulse repetition rate transmitter and samples return signals at 400 MHz. A field-programmable gate array is programmed to generate and accumulate real-time periodograms representing average power spectra of the Doppler shifted echo from a series of more than 60 range gates, where each range gate is 48 m. The accumulated periodograms are streamed to a host computer for subsequent processing to yield the line-of-sight wind velocity. Wind velocity estimates with a precision value of 0.08 m/s can be made under nominal aerosol loading and nominal atmospheric turbulence conditions for ranges up to 3 km. Wind velocities and aerosol profiles are obtained while scanning the pointing direction of the lidar, thus producing both horizontal and vertical representations of the wind vectors.