An Energy-Efficient Collaborative Scheme for UAVs and VANETs for Dissemination of Real-Time Surveillance Data on Highways

In addition to military applications, Unmanned Aerial Vehicles (UAVs) are now finding their ways in civilian and public domains. Surveillance of highways with the use of a helicopter is a costly option that could be replaced with a more economical option of UAVs. Unlike MANETs in general and VANETs in particular, UAV networks have unique characteristics due to the association of factors like dynamic topology, high mobility, and limited energy. Keeping in view the real-time aspect of road surveillance, the use of UAVs with the existing routing protocols is not a straight forward option. A fleet of drones en route to surveillance on the highways may face frequent link failures due to its dynamical sparse linear architecture. To compensate for the sparse topology, a collaboration of UAVs with VANETs might be a good choice but as such integration of the two networks could create too much overhead. In this article, a proactive energy-efficient and reliable Collaborative scheme between UAVs and VANETs, termed as CUV, is presented. To avoid flooding in the entire network, Base station Association Messages (BAM), in a unicast manner, are forwarded till the end-nodes. Although BAM is received by each node which ensures connectivity with the BS but only certain nodes are allowed to retransmit. Furthermore, to take care of the loss of BAM messages due to the presence of hidden nodes, a novel mechanism for link repair inside a BAM interval is introduced. The proposed scheme is simulated in Network-Simulator-2 and compared with the well known proactive OLSR and reactive AODV protocols.