We consider an unmanned aerial vehicle enabled (UAV-enabled) fog-radio access network (F-RAN) in which UAVs with caching and cooperative communications capabilities. We formulate the content placement as an optimization problem and derive the optimum probabilistic content placement based on the number of popular contents need to be cached at UAVs, where this depends on the content library size, the cooperation zone of UAVs, and content popularity distribution. We further study indicate that cooperative communication plays an essential role in UAV-enabled edge communications as it effectively curbs the impact of dominant received interference. It is also seen that cooperative cache-enabled UAV F-RAN performs better in highrise environments than dense urban and sub-urban environments.
because of blockage by the high-rise buildings, and the performance gain of cooperative communication on the attending signal. Comparing the performances of the developed content placement strategy and conventional caching techniques shows that our proposed randomized caching outperforms the others in most of the practical cases.