Research on Space Diversity Technique of Laser Atmospheric Communication Based on MIMO

Space diversity is one of the important techniques of overcoming the influence of atmospheric turbulence on laser communication. Having analyzed the theory of diversity technique, the paper has focused on researching the space diversity technique and established the joint probability density function of the threshold value. Outage probability is studied in laser communication and get the variation curve of power gain and the number of antenna in different atmospheric turbulence. Based on the BPSK modulation mode, the bit error ratio mode of the multi-input multi-output (MIMO) is set up and reach the conclusions that maximum power gain is obtained with an equal amount of transmitting antenna and receiving antenna and the total amount should be not greater than nine. The space diversity technology can effectively reduce the bit error ratio of the system.