So Mr O'Brien has been working on a ceiling-based system that tracks where a receiving device is, and then sends it a signal using several laser beams from a directional transmitter.

The transmitter beam is Gaussian for real satellite-ground laser communication system. The pointing jitter and atmospheric scintillation are the main noise sources for satellite-ground laser link.

This thesis emphasizes on solving series key techniques in theory analysis, simulations and prototype development, the laser transmitter prototype of range-gated imaging system has been developed.