الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
A Vehicular Ad-Hoc Network (VANET) is a technology that uses moving cars
as nodes in a network to create a mobile network. During the last decades,
Intelligent Transportation System (ITS) has progressed at a rapid rate, which aims
to improve transportation activities in terms of safety and efficiency. Car to Car or
Vehicle-to-Vehicle (V2V) communications and Car/Vehicle-to-Infrastructure (I2V
or V2I) communications are important components of the ITS architecture.
Communication between cars is often referred to Vehicular Ad-Hoc Networks
(VANET) and it has many advantages such as: reducing cars accidents,
minimizing the traffic jam, reducing fuel consumption and emissions and etc.
This research contributes to study and develop traffic congestion detection
algorithms. This thesis aims to enhance the performance of vehicular ad hoc
networks by presenting a new algorithm for detecting traffic congestion where
facing this problem has a great impact on VANETs performance. Our proposed
algorithm is Non Periodic Traffic Congestion Detection (NPTCD) allows vehicles
to inform each other about congestion areas and avoiding it. The vehicle analyzes
traffic data then makes a decision about congestions. The vehicle broadcast
warning message to all other vehicle about congestion so driver can avoid blocked
road. The performance of the proposed algorithm “NPTCD” has been compared
with the recent existing algorithms such as SOTIS, VOTING and Lin. Those
algorithms aim to detect traffic congestion at same concepts of our proposed.
The performance of the proposed approach has been evaluated with the aid of a
simulation platform. This platform integrates a microscopic traffic simulation,
SUMO, and a communication network simulator, OMNET++ has been used. The
integration of both simulators is a key solution to several research problems both
on the communications side and on the transportation side.
Simulation within simulators platform applied on real maps for three cities here
in Egypt to test the performance of our algorithm in real world and comparing it
with other algorithms, introduced by other researches. For simulation we chose
three different maps for three cities Cairo, Sadat and Shebin El-Com. Each city has
special road characteristics. The results of simulations show the capability of
proposed algorithm in reducing number of vehicles in congestion and introduces
more awareness between vehicles, all this with less overhead of messages on the
communication network.