Remote measurement of HCl, CH_4, and N_2O using a single-ended chemical-laser lidar system

Abstract

The applicability of the high energy discretely tuned DF laser for remote measurement of HCl, CH(4), and N(2)O has been investigated. A single-ended or monostatic lidar system using radiation backscattered from topographical targets was tested. Selective absorption of the backscattered signal was used to infer concentration of gaseous species. Good agreement was obtained between the lidar measurements and the concentrations determined by in situ measurements in the remotely positioned sample chamber. The lowest measurable material concentration for each gas was inferred from random fluctuations in the measured concentration. Sensitivity of the existing system to HCl, CH(4), and N(2)O was found to be 0.05 ppm-km, 6.0 ppm-km, and 0.24 ppm-km, respectively. An N(2)O plume was also measured in the open atmosphere between the lidar system and a foliage target to demonstrate system capabilities under typical field conditions. Performance predictions indicate that total burden and range-resolved species concentration measurements are feasible to a range of 10 km or more with commercially available components.

Space-borne remote sensing of CO2, CH4, and N2O by integrated path differential absorption lidar: a sensitivity analysis

“…Differential absorption lidar (DIAL) measurements of range-resolved CO 2 profiles using a pulsed single-frequency Tm:Ho:YLF laser at 2.05-µm wavelength in combination with heterodyne detec-tion principles are reported in [19]. Only two active remote sensing systems for the detection of N 2 O have been developed yet [20,21]. Both systems use the topographic target return of a pulsed chemical laser (DF) at 3.9 µm.…”

Energy calibration of integrated path differential absorption lidars

“…In the past, IPDA applications have used either separate pyroelectric detectors [28][29][30] or photodiodes to normalize the pulse intensities [31]. Also, in more recent developments, separate photodetectors are usually used as the transmitter monitor [4,6,32].…”

Development of a Lidar System for Measuring Methane Using a Gas Correlation Method

“…[1][2][3][4][5][6][7][8] Most of these techniques require a single-mode laser or a high-accuracy scanning of the laser wavelength. However, in general, controlling these lasers is difficult for field measurements, where vibrations and changes in temperature are inevitable.…”