Abstract:
In recent years, Vehicular Ad-hoc Networks (VANETs) have become an important
part of Intelligent Transport Systems (ITS). The presence of such these networks
opens the way for a wide range of applications such as safety applications, mobility
and connectivity for both driver and passengers. One of the big challenges facing
VANET system is a high traveling speed situation of vehicles. A key problem in
such environment is the data exchange between neighbour vehicles must be
supported with high level of QoS. Thus, new MAC protocols and standards are
needed especially for different safety applications to deal with this dynamic
environment changes in which accidents can happen within tens of milliseconds.
Conventional VANET dynamic routing protocols do not cater for dynamic
system conditions encountered in VANETs. Most of the existing VANET protocols
optimize hop count as building a route selection which is alone may case quality
degradation. However, with the invention of new applications and services,
efficiency of these models lags behind the acceptable Quality of Service (QoS)
standards. There is a strong need to consider a metric such as quality-based channel
quality state reporting and feedback with channel state information (CSI) in order to
select a good quality links.
In order to meet such QoS standards, this thesis proposes a Cross Layer Design
(CLD) routing approach based on IEEE 802.11p vehicular standard. Two additional
design metrics including the strength of received power that gives an indication of
link utility function (T) and Signal to Noise Ratio (SNR) are used for route selection.
Those route metrics comes from CLD that enables sharing of information between
physical and MAC layers. In fact, CLD has enormous potential in communications
environment to define a good level of link quality for a specific type of applications.
In this work, the performance of the proposed CLD approach based on IEEE
802.11p by using MATLAB is evaluated in terms of delay, average throughput and
Packet Delivery Rate (PDR) for different city/highway scenarios. Performance of the
proposed routing architecture is evaluated and the results proved that the proposed
technique enhance the QoS metrics. Simulation results show that our proposed
scheme outperforms the traditional dynamic VANET routing protocols in terms of
delay, average throughput and PDR.
