Multi-UAV Relay Connectivity Optimization for Heterogeneous Users Based on Load Balancing and Throughput Maximization

Abstract

By relaying messages between users, unmanned aerial vehicles (UAVs), which are frequently utilized in the communication industry, can be used as airborne communication relays to resolve connectivity problems. In order to effectively connect a large number of heterogeneous users dispersed on the ground, we deploy a large number of UAVs for reliable relay coverage and message transmission between users. We initially put forth a relay coverage algorithm that continuously optimizes the position of UAVs and the cell division of terrestrial users in order to provide users with full coverage. Second, we study several relay message forwarding methods between UAVs while taking into account the features of heterogeneous users. A relay selection method, which takes the relay link throughput as the optimization goal, is proposed to ensure full connectivity between UAVs. Finally, we contrast and analyze how various relay forwarding methods affect the effectiveness of the relay network. The experimental results demonstrate that the proposed relay coverage algorithm can balance the UAV relay load better and reduce transmission delay, while the suggested relay selection strategy can minimize the number of isolated UAVs and maximize the throughput of UAV relay links.INDEX TERMS UAV, relay connectivity, heterogeneous users, relay message forwarding, load balancing, throughput. I. INTRODUCTIONDue to their low cost and flexible deployment, UAVs [1,2] have found extensive usage in the military, civil, and commercial fields for operations like swarm operation [3], emergency rescue [4], and security [5]. For instance, when the ground-based communication infrastructure is destroyed by the natural disaster, UAVs can be used to establish temporary communication links to support rescue operations.It can be seen that connectivity issue is a major concern for ensuring that users have reliable communication links. Users that are unable to contact directly can still establish connections by forwarding messages owing to the communication relay [6][7][8][9]. Direct communication is actually prevented by a wide range of barriers, including over-thehorizon communication that occurs outside the connection range, link interruption due to interference in complex situations, incompatible communication systems that prevent direct communication between heterogeneous users, and so on. The communication relay technology [10][11][12] can offer effective answers to these problems. From the perspective of the causes behind the requirement for relaying, it can be said that communication relay technology addresses two main connectivity issues: the first is the connectivity issue of overthe-horizon communication, and the second is the connectivity issue of incompatible communication systems.Owing to the unique advantages, UAVs are frequently utilized as airborne base stations and aerial relays in the communication field to establish wide-area coverage connection, giving users access to reliable, timely, and ondemand communication services [13][14][15][16][17]. ...

Location and User Association Optimization in Multiple Radio Access UAV-Assisted Heterogeneous IoT Networks

“…Their objective is to maximize the users sum rate by jointly optimizing the 3D location of the UAV, the communication bandwidth, and the power allocation of the UAV and the ground base stations. In [23], the authors considered multiple UAVs for reliable relay coverage and message transmission between diverse users. They proposed a relay coverage algorithm that optimizes the UAVs position continuously and the cell division to provide users with full coverage.…”