Laser Radar Technology

Laser Radar LIDAR is a transceiver system which measures the amount of light returned to a receiver due to backscattering of the transmitted signal from the intervening media gases, droplets, and aerosols. Besides providing a ranging capability, LIDAR is important tool for the monitoring of atmospheric diffusion processes. The usefulness of such a system is most evident in light of the fact that backscattered energy which is detectable to the receiver provides an observer with a multitude of information about the small volume of atmosphere which caused the scattering. Since several highly variable atmospheric parameters define the amount and manner of light scattering, hence the amount of energy returned, numerical models of the atmosphere are constructed which account for the fluctuations of the returned signal, in terms of the controlling atmospheric parameters. Thus the amplitude of the signal returned is an anomalous measurement of the state of the atmospheric volume which caused the scattering. In order to relate the atmospheric variables to the LIDAR system variables, an exact equation which describes the motion and interaction of the signal beam with the atmosphere must be developed and modeled. A discussion of the implications and significance of the scattering equations and parametric relationships is undertaken, in an attempt to isolate concentration of the atmospheric volume as a measurable quantity in terms of system variables.