Design of a LIDAR signal processing system

Abstract

Laser radar or LIDAR which is an acronym for light detection and ranging is a remote sensing technique of probing the atmosphere. Figure 1 shows the basic elements, consisting of the laser with its transmitting optics, the telescope with its receiving optics, and the signal processing unit which is composed of the transient digitizer, signal averager and the display unit. A collimated laser pulse is propagated into the atmosphere which interacts with various scatterers such as aerosols, gas molecules or solid targets. As a result, a small portion of the lasers energy is back-scattered and could be collected by a receiving telescope, transmitted through a spectral filter and detected by a photodetector. The electrical signal is processed in order to gather physical as well as chemical information from the different scatterers involved in the interaction.
In this paper, a design of the lidar signal processing system is presented. Figure 2 shows the schematic diagram of the system consisting of the signal conditioner, the transient digitizer, the signal averager and the display units.