With the rapid development of cloud computing and big data, traditional Vehicular Ad hoc\nNetworks (VANETs) are evolving into the Internet of Vehicles (IoV). As an important communication\ntechnology in IoV, IEEE 802.11p protocols have been studied by many experts and scholars. In IEEE\n802.11p, a nodeâ??s backoff counter will be frozen when the channel is detected as busy. However,\nmost studies did not consider the possibility of continuous backoff freezing when calculating delay.\nThus, in this paper, we focus on the performance analysis of IEEE 802.11p for continuous backoff\nfreezing. Specifically, we establish an analytical model to analyze the broadcast performance in\nthe highway scene where vehicles can obtain traffic density from roadside units through Vehicle to\nInfrastructure (V2I) communications. We first calculate the relationship between vehicle density and\nthe number of vehicles. Then, we derive the relationship between the number of vehicles and packet\ndelay according to Markov chains. Next, we utilize the probability generating function (PGF) to\ntransform traditional Markov chains into z domain under the situation of non-saturation. Finally,\nwe employ the Mason formula to derive packet delay. As compared with the performance without\nconsidering the continuous backoff freezing, the simulation results have demonstrated that our\nanalytical model is more reasonable.
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