Cooperation-Assisted Spectrum Handover Mechanism in Vehicular Ad Hoc Networks

Abstract

Due to the rapid development of wireless network technology, a variety of application services have been proposed. Recently, the Internet-of-vehicles (IoV) has received lots of attention from industry, government, academics and research units. Unfortunately, the wireless spectrum resources are very limited. There are some problems in vehicle ad hoc networks (VANETs), such as channel interference, competition and waste of wireless spectrum. Although cognitive radio technology has been proposed to improve spectrum utilization, there are still many issues that need to be addressed. For example, when a vehicle hands over the base stations (BSs), the issue of the spectrum handover needs to be considered. The network performance gets worse as the vehicle moves faster. Therefore, this paper proposes a cooperation-assisted spectrum handover (CASH) scheme. In CASH, each vehicle uses cognitive radio technology to collect the surrounding spectrum information, exchanges information by vehicle-to-vehicle collaboration technology and then executes a pre-scan mechanism to improve performance. We hope that the proposed method can reduce the delay time of the spectrum handover and improve the spectrum utilization. Finally, the simulation results show that our proposed method outperforms other existing schemes. In spectrum utilization, CASH is about 25% better than that of the traditional method. In average scan time, the time of CASH is about 5 times less than the time of the traditional full scan method.