A CCH Cycle Adaptive Algorithm for IEEE 802.11P Mac Protocol in Safety Applications

Abstract

The IEEE 802.11p standard, especially the 802.11p MAC protocol, has attracted much attention as part of the WAVE protocol in VANETs. Safety applications are very challenging for the design of MAC protocols due to their low latency and high reliability requirements. The CCH interval is also a key parameter for the 802.11p MAC protocol since it can affect the performance of delivering safety messages significantly. In this paper, a simulation based evaluation is proposed firstly to evaluate the performance of the 802.11p MAC protocol with various vehicle densities and CCH interval settings. Based on the simulation results, a CCH cycle adaptive algorithm for the 802.11p is then proposed. In this, the CCH interval is adjusted according to the vehicle density. The simulation results show that the proposed algorithm outperforms the IEEE 802.11p MAC protocol in terms of channel utilization and reliability in safety applications.