Construction And Performance Analysis Of HLA-based VANET Simulation Platform

The research of VANET (Vehicular Ad hoc Network) simulation has gained more and more attention in recent years. VANET Simulation, which involves both microscopic traffic simulation and communication simulation, has become an important method in evaluating VANET network performance. The latest research is more willing to make use of approach of co-simulation combination of traffic simulation and communication simulation. A HLA based VANET simulation platform is setted up in this thesis and a series of simulations and researches on method of improvement about existing problem of VANET are conducted with this platform.Firstly, HLA (High Level Architecture) based VANET simulation platform is designed with microscopic traffic simulator Paramics, communication simulator OPNET and HLA Console. Both traffic simulator and communication simulator work as federates in the HLA simulation platform, which are based on the analysis of the characteristics of VANET simulators. The HLA based VANET simulation platform has a great advantage over other simulators in scalability. The simulation scenario is built according to the layout of test site in Langfang, Hebei, where the test and demo of863key projects "CVIS key technology" are implemented.Secondly, on the issues of high latency and high packet loss rated in VANET, extensive simulations are run under different simulation conditions in this thesis. It is found that the frequent interruptions of wireless routes are the main cause of the high latency. And it is concluded that the location-based routing protocols be superior to the topology based routing protocols in VANET.Finally,RSUs(Road Side Unit) are added in the VANET to improve the network performance in the simulation. Extensive simulation and analysis are implemented with different densities and layout of the RSUs. The results show that the VANET network performance of lowest end-to-end delay and highest packet delivery ratio can be achieved only when the density of RSU increases to a certain threshold, and further increasement of the density of RSU cannot improve network performance any more. The performance with different packet intervals, different data rates of MAC layer and different speed of vehicle is also simulated, and the required ranges of packet intervals, data rates and vehicle speed are obtained.