On the uplink transmission of satellite–aerial FSO links in presence of random optical interference

Profiting from its flexibility in interconnecting mobile terminals in the air and/or on the ground, satellite–aerial/terrestrial communication has been regarded as a promising solution to realize global seamless coverage. In this work, a free-space optical (FSO) satellite–aerial communication system is considered, in which a source aerial terminal (S) delivers its information to a satellite receiver (D) while an interfering aerial terminal (I) sends an optical interference signal to the receiver at D. Due to their natural characteristics, the positions of the aerial terminals exhibit strong randomness, which cannot be ignored during the performance modeling and optimization. By applying stochastic theory, this work investigates the influence of the randomness of I's position on the uplink transmission performance of the considered systems, while I is uniformly distributed in a spherical space with the spherical center, S. Specifically, FSO is adopted for the information delivery between S and D. Then, exact/approximated/asymptotic closed-form analytical expressions of the outage probability, coverage probability, and ergodic capacity of the target uplink communication link are derived, respectively. Finally, numerical results are presented to verify the proposed analytical models, and some meaningful conclusions are reached.