A COMPACT SOLID-STATE RANGE SENSOR WITH MILLIMETER DEPTH RESOLUTION

THE GOAL OF THIS PROGRAM IS TO DEMONSTRATE A HIGH-RESOLUTIONACTIVE RANGING SYSTEM USING LOW-TEMPERATURE-GROWN (LTG) GAAS PHOTOCONDUCTORS AS DEPTH SENSORS. THESE NEWLY-DEVELOPED SOLID-STATE DEVICES ARE CHARACTERIZED BY AN EXCEPTIONALLY BROAD FREQUENCY RESPONSE (UP TO 375 GHZ @ -3 DB) AND A VERY HIGH SENSITIVITY (70% QUANTUM EFFICIENCY). TO REDUCE THE NOISE BACKGROUND THEY CAN BE GATED ON A PICOSECOND TIME SCALE. LOW-TEMPERATURE-GROWN GAAS PHOTOCONDUCTORS ARE COMPACT, STURDY, AND EFFICIENT. DURING THIS PHASE I WE WILL STUDY THE RANGE AND THE RESOLUTION OF AN ACTIVE RANGING SYSTEM USING LTG GAAS SENSORS. THIS SOLAR-BLIND, ACTIVE RANGING SYSTEM WILL BE ABLE TO OPERATE IN ENVIRONMENTS WITH HIGHLY-VARIABLE ILLUMINATION. A CORRELATOR EMBODIMENT WILL PROVIDE MILLIMETER DEPTH-RESOLUTION AND RANGE EXTENDING TO SEVERAL HUNDRED METERS.