Mitigation of atmospheric turbulence on up and downlink optical communication systems using receiver diversity and adaptive optics

Abstract

Improvement in the performance of uplink and downlink optical communication systems by means of receive diversity and adaptive optics correction is investigated. We develop a communication system model using adaptive optics correction in the transmitter and maximum ratio combining diversity technique in the receiver. The effect of adaptive optics correction modes, receive diversity, zenith angle, link length, wind speed and the height of transmitter/receiver on the ground are evaluated. Performance improvement is observed with both adaptive optics correction and the receive diversity. It is aimed to provide researchers an option to determine the method they will use to reduce the effect of turbulence. As the numerical values of the main results, we report that adaptive optics correction with 5 mode Zernike removal reduces BER from 1 0 - 8 to 1 0 - 10 for one receiver. When the number of receivers is 6, BER is found to reduce from 1 0 - 6 to 1 0 - 12. The results obtained in this study can be beneficial to optimize the design of the slant path uplink and downlink optical communication links between the ground and low-orbit satellites that are exposed to atmospheric turbulence.