Single peak atomic frequency discriminator for 589 nm Doppler lidar

A single-peak atomic frequency discriminator (SPAFD) specifically designed for 589 nm Doppler lidar systems has been developed, which integrates both narrowband filtering and high-precision frequency discrimination capabilities at 589 nm. The SPAFD exhibits a peak transmittance of 70% and a full width at half maximum (FWHM) of 2 GHz. The detection sensitivity has been validated through theoretical simulations and experimental verification. By integrating the SPAFD into a 589 nm three-frequency Doppler lidar system, the system retains its capability for daytime wind field detection in the mesopause region while enabling daytime wind profiling from the troposphere to the stratosphere. Continuous 5-hour daytime wind observations are demonstrated, achieving a temporal resolution of 1 hour and a spatial resolution of 1 km, with a wind speed uncertainty of ±5 m/s at 40 km altitude in daytime. With future improvements of the 589 nm laser power and repetition rate, the SPAFD will enable the lidar system to achieve daytime wind measurements across the full-altitude atmosphere.