Measurement of faint lidar signals in the presence of an intense background during pulsed laser sounding of the atmosphere

A technique for measuring faint lidar signals during the pulsed sounding of the atmosphere in the presence of an intense background is proposed and analyzed. The technique is based on the measurement of the background in the course of a time tau greater than tau sub 0 between two consecutive measurements, where tau sub 0 is the duration of the total signal (signal plus noise). The accuracy of the measurements is analyzed, and it is shown that the proposed technique is of maximum efficiency for a background intensity significantly higher than the signal intensity and/or for a high level of background fluctuations.