Pulse averaging methods for a laser remote monitoring system using atmospheric backscatter

Three methods for averaging differential absorption lidar (DIAL) measurements are discussed. They are compared using experimental data acquired with a dual-laser direct-detection DIAL system operating in the near UV using atmospheric backscatter. The data set was acquired with the two lasers tuned to the same wavelength to eliminate any spectral variations and fluctuations of differential absorbers from the measurement. The results are compared by evaluating both the standard deviations and the means of the integrated columns. The results suggest that shot noise on the backscattered signals dominates the measurement statistics and considerably reduces the necessity for short interpulse delay times.