Acquisition and tracking of image beacon for deep space optical communication

With laser to return the scientific data of deep space exploration to earth, the up beacon cannot provide enough tracking rate for its serious optical attenuation, so the image of a natural object is usually used as the beacon. Successful acquisition and beacon tracking is the key of setting and keeping the deep space optical communication link. Storing an image in the aircraft as the reference, using the correlation of the reference image and the detected image to acquire the beacon, the theoretical analysis and computer simulation show that it can accurately confirm the initialized pointing direction of the optical antenna and make PAT subsystem enter the tracking model. Calculating the translation of beacon based on discrete Fourier transform (DFT) and maximum likelihood criterion, need solve two nonlinear equations, and the linearly approximated result shows that the total translation error is below 0.5 pixel, the translation error in X direction is 3.3%, and the translation error in Y the direction is 2.7%, can meet the need of deep space optical communication, so it is a feasible scheme.