Raman lidar for remote sensing of gas

Abstract

Raman lidar is an active remote sensing technology that has been widely applied in fields such as laser atmospheric transmission, global climate prediction, aerosol radiation effects, and atmospheric environment. Raman lidar has the ability to measure target distances and provide spatial depth resolution. It offers high sensitivity and a long detection range without the need for cooperative targets. In this study, a pulsed laser with a wavelength of 355 nm and a single-pulse energy of 350mJ was used as the light source. The spectrometer system employed a blazed grating and a narrowband filter. Signal acquisition was performed using a 450 mm diameter Cassgrain telescope, and a single-photon detector was utilized to enhance the extraction and detection of Raman signals. Outdoor telemetric measurements of dimethyl methylphosphonate (DMMP) gas were conducted. In the vehicle moving mode, target gases could be detected up to a distance of 1.8 km. In the stationary mode, target gases could be detected up to a distance of 5 km.