High-energy <inline-formula><math altimg="none" display="inline" overflow="scroll"><mrow><mn>2</mn><mspace width="0.3em" /><mi>μ</mi><mi mathvariant="normal">m</mi></mrow></math></inline-formula> Doppler lidar for wind measurements

Abstract

A coherent Doppler lidar at 2 µm wavelength has been built with higher output energy (100 mJ) than previously available. The laser transmitter is based on diode-pumped Ho:Tm:LuLiF, a recently developed laser material that allows more efficient energy extraction. Single-frequency operation is achieved by a ramp-and-fire injection seeding technique. An advanced photodetector architecture is used incorporating photodiodes in a dual-balanced configuration. A digital signal processing system has been built, allowing real-time display of wind and aerosol backscatter data products. The high pulse energy and receiver efficiency provides for measurement of wind fields to ranges not seen before with 2 µm lidars, and example wind measurements were made to show this capability.