Effect of Lateral Alignment Error on Communication Performance of Space Chaotic Optical Communication System

In space chaotic optical communication system, when chaotic signal is coupled into the fiber at receiving terminal, it will be affected by the lateral alignment error. To study the influence of it on space chaotic optical communication system, this paper analyzed two kinds of mismatches brought by lateral alignment error, then we give a calculation model of bit error rate under lateral alignment error. Based on the model, we conducted numerical simulations. Results show that the effect of lateral alignment error on external mismatch is greater than the effect of it on internal mismatch and the system will be affected more by lateral alignment error which caused by random angular jitter than caused by static bias error. Besides, further analysis found that in high-precision space chaotic optical communication system, compensating for internal mismatch can effectively reduce the effect of lateral alignment error on system. The results will be helpful for optimizing the design of space chaotic optical communication system.