Raman lidar system for methane gas concentration measurements

Abstract

The design of a Raman lidar system for methane gas concentration measurements is described. The system measures concentrations in the 2–20% range in air at ranges from 100 m to 1 km with an accuracy of ±10%. Design criteria for the transmitter, receiver, scanner, and data acquisition subsystems are discussed. The primary components are an excimer laser source, a two-channel 0.5-m diam telescope, and a high-speed signal averaging circuit. Results of calibration measurements are presented.