English abstract
Rapid developments in the field of transportation have transformed our ways of commuting from one place to another. This development has also been a major cause of road accidents and fatalities for the human beings worldwide. In an attempt to make the roads safer with lesser number of accidents and fatalities, Vehicular Ad Hoc Networks (VANETs) is proposed by the research community. In such networks, vehicles are modeled as nodes that have the capability to communicate with one another. Such communications may prevent accidents, thus making roads safer to everyone.
There are two common methods for studying VANETs, namely: Simulations and Field testing (prototyping). Various research projects have given solutions for fulfilling the technological requirements in VANETs, using simulations, but currently the focus is shifting from simulation-based modeling, into more practical implementation and experimental field tests. The primary objective of this thesis is to evaluate performance of a single-hop periodic broadcast communication, known as beacons or HELLO packets, in terms of Packet Delivery Ratio (PDR) and message delivery delay through experimental field tests. The secondary objective is to compare some of the results obtained through field tests with simulations. The experimental process acquires information from each node in the network (e.g. nodes' speed, location, and node ID). This information is then disseminated periodically to all the surrounding nodes in the network. A total of four nodes have been deployed for the field tests due to complexity of the tasks on the express way.
The effect of varying parameters such as speed, mobility, node density and road environments on the PDR and Packet End-to-end Delay are studied. The results of the experiments reveal that a constant relative velocity for all nodes in the network did not have a significant impact on the PDR for the considered VANET topology, whereas node density and road surroundings created a noticeable impact on the PDR. In addition, Packet End-to-end Delay increases with node density and packet size, while it remains unaffected by inter node distance of up to 450 meters. These results will contribute improving the current simulation models for a better performance analysis of VANETS.
