ARHet: An Asymmetric Link-Based Routing Protocol in Heterogeneous Multi-Radio FANETs

Flying Ad Hoc Networks (FANETs) formed by Unmanned Aerial Vehicles (UAVs) with multiple heterogeneous radios are increasingly being adopted for various applications. However, the presence of asymmetric links caused by hardware differences poses challenges to common routing protocols designed for homogeneous FANETs. Ignoring asymmetric links may lead to inefficient resource utilization and compromise network connectivity, resulting in a significant decline in the performance of existing protocols. How to fully utilize the abundant link resources to enhance the network performance and offer more routing options for data with diversified service requirements, is a challenging task. In this paper, we propose an asymmetric link-based routing protocol in heterogeneous multi-radio FANETs, named ARHet. To efficiently exploit the asymmetric links, we first propose an asymmetric link discovery and information feedback mechanism. Then, to satisfy the specific service requirement of each type of data, we propose a traffic-differentiated routing strategy that can establish the appropriate paths for them. Experimental results show that ARHet can improve the delivery ratio by 20 %, increase the throughput by 31 %, and reduce the overhead by 69 % compared to the other benchmarks. In addition, ARHet can achieve a better differentiated service performance.