Acquisition and tracking for star as beacon in deep space optical communication

A method to acquire and track the beacon for deep space optical communication system is proposed, which uses star as beacon, and controls the direction of down beam based on the absolute position in inertial frame, the ephemeris of aircraft and earth and the attitude of aircraft. Theory analysis and computer simulation show that the precision and focus of star tracker, the divergence angle of down beam influence the probability of laser link setting up. When the divergence angle of down beam is 30 μrad, the field of view is 8° × 8°, the focus is 143 mm, and when the error of the center of star is 0.10 pixel, the probability of the laser link setting up will reach 96.4%.