Safeguarding UAV Networks against Active Eavesdropping: An Elevation Angle-Distance Trade-Off for Secrecy Enhancement

Because of their low expense and ease rapid deployment, unmanned aerial vehicles (UAVs) are frequently applied in wireless networks. Although the channel is able to broadcast, legitimate communications between UAVs ground nodes incredibly susceptible severe security threats, such as malicious jamming eavesdropping. Compared with traditional line-of-sight (LC) model, probabilistic LC (PrLC) model can better describe practical conditions UAV-to-ground transmission city areas. Therefore, this paper considers UAV-enabled networks under PrLC complex environments. Specifically, when UAV transmits classified messages nodes, multiple active eavesdroppers simultaneously eavesdrop on transmitted confidential information interfere signal limit legal transmission. We jointly optimize communication connection, three-dimensional (3D) trajectory, transmit power increase average secrecy rate for worst condition. problem non-convex, best solution formidable get, designs an iterative algorithm use successive convex approximation (SCA) technique solve it. other benchmarks, our proposed algorithm, demonstrated by numerical results, effectively balance elevation angle-distance trade-off improve performance.