Antenna parameters for incoherent backscatter heterodyne lidar.

The antenna and beam geometry of lidar systems employing heterodyne reception of incoherent backscatter signals are discussed. Particular emphasis is placed on systems where the target extends uniformly across the transmitted beam using topographic targets or atmospheric backscatter. The geometry is assumed to be circularly symmetrical, but otherwise arbitrary obscurations are permitted. The effects of atmospheric scintillation are neglected. Parameters are defined which characterize the system efficiency, and the conditions under which these parameters may be maximized are considered.