Remote sensing of CO using frequency-doubled CO2 laser radiation

Abstract

Single-ended remote sensing measurements of the atmospheric concentration of CO using differential absorption of line-tunable, frequency-doubled CO2 laser radiation near 4.6 μm are reported. The concentration of CO was deduced from laser backscatter returns from topographic targets at ranges up to 2.5 km with an overall uncertainty of approximately 10 ppb. The use of several targets at different ranges but along the same line of sight permitted pseudo-range-resolved measurements and clearly established the strong localization of CO concentration over traffic roadways.