3-D SURVEILLANCE LASER TECHNIQUES.

Abstract : The purpose of this program is to produce an experimental laser radar system which provides range and angle information to accomplish airborne ground surveillance at high data rates with high resolution. To accomplish this task, RCA is using a double-doped YAG laser (YAG:Nd(3+) - Cr(3+)) operating at a high pulse repetition rate (80 kHz) and high peak power (160 W) in conjunction with a sensitive photodiode detector. To achieve the high scanning rate (125 scans/s), a unique prismatic scanner is being developed which allows the transmitter and receiver to be scanned coaxially with very narrow beamwidths. The principal problem is in the laser area in establishing good self Q-switching but steps have been taken to deal with this in the form of experimentation of the Laser. These experiments involve varying the doping concentrations of the laser crystal, and varying the coupling coefficients, and cavity characteristics and drive level.