Opportunistic UAV Utilization in Wireless Networks: Motivations, Applications, and Challenges

Abstract

With the prominent advancement of flight control and intelligent transportation technology, UAVs will play an important role in air traffic. Besides being deployed as dedicated aerial communication platforms, a large proportion of UAVs will be operated by different companies with various flight missions. In the existing literature, such UAVs are usually treated as consumers of spectrum resources. However, they may also bring opportunities of air-ground line-of-sight and relay links, which can improve the transmission optimization of ground networks. This article explores the opportunistic assistance of such UAVs for ground networks from a new perspective, called OUU. Various opportunistic transmission models and corresponding application scenarios are introduced according to different flight modes of UAVs, including opportunistic data dissemination, collection, caching, computing, and forwarding. Two preliminary cases demonstrate that effective OUU models can improve network performance without relying on dedicated deployment of aerial communication platforms, and thus alleviate the aerial traffic congestion issue. After discussing the challenges brought by large-scale and highly dynamic UAV networks, this article further enumerates the promising research directions and related optimization frameworks for the OUU model.