Summary: | Vehicular communications occur when two or more vehicles come into range of one another, to share data over wireless media. The applications of this communication are far-reaching, from toll collection to collision avoidance. Due to the proliferation of wireless devices and their ubiquitous nature it is now possible to operate in an ad hoc manner between transmitting stations. Vehicular ad hoc networks (VANET) are a special kind of network, that experience short link times and high levels of interference, but have the ability to present many driver information and safety solutions for the worlds roads. Computer simulation of VANET enables rapid-prototyping and intensive exploration of systems and protocol, using highly complex and computationally expensive models and programs. Experimentation with real vehicles would be time consuming and expensive, limiting the range of study that could be achieved and therefore reducing the accuracy of analytical solutions exposed through experimentation. An extensive corpus of work on networking, traffic modelling and parallel processing algorithm has been reviewed as part of this thesis, to isolate the current state-of-the-art and examine areas for novel research. In this thesis the value and importance of computer simulation for VANET is proposed, which explores the applications of a high-fidelity system when applied to real-world scenarios. The work is grounded on two main contributions: 1) that by using intervehicle communication and an advanced lane changing/merging algorithm the congestion that builds up around an obstruction on a highway can be alleviated and reduced more effectively than simple line-of-sight, even when only a proportion of the vehicles are radio equipped. 2) that the available parameter space, as large as it is, can be efficiently explored using a parallel algorithm with the NS-3 network simulation system. The large-scale simulation of VANET in highway scenarios can be used to discover universal trends and behaviours in the successful and timely delivery of data packets. The application of VANET research has a broad scope for use in modern vehicles and the optimisation of the transmission of data is highly relevant; a large number of parameters can be tuned in a networking device, but knowing which to tune and by how much is paramount to the operation of intelligent transport systems.
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