PROBLEM TO BE SOLVED: To provide a system which tracks an optical communication beam in free space. SOLUTION: Modulated light beam 12 is divided by a beam splitter 24. The light beam is partially converged on a high speed photodetector 26. The other modulated light beam 12 is passed through a target pattern optical element 32. As a result, a target pattern is formed on a two-dimensional active pixel sensor array 34. The alignment of a system 10 is adjusted based on the position of a target pattern on the array 34.
SYSTEM AND METHOD FOR OPTICAL COMMUNICATION BEAM TRACKING AND FOR DATA RECEIVING FROM THE BEAM