VANET Modeling and Clustering Design Under Practical Traffic, Channel and Mobility Conditions

VANET Modeling and Clustering Design Under Practical Traffic, Channel and Mobility Conditions

ABSTRACT:

In Vehicular Ad Hoc Networks (VANETs), vehicles driving along highways can be grouped into clusters to facilitate communication. The design of the clusters, e.g., size and geographical span, has significant impacts on communication quality. Such design is affected by the Media Access Control (MAC) operations at the Data Link layer, the wireless channel conditions at the Physical layer, and the mobility of the vehicles. Previous works investigated these effects separately. In this paper, we present a comprehensive analysis that integrates the three important factors into one model. In particular, we model an unsaturated VANET cluster with a Markov chain by introducing an idle state. The wireless channel fading and vehicle mobility are integrated by explicitly deriving the joint distribution of inter-vehicle distances. Closed-form expressions of network performance measures, such as packet loss probability and system throughput, are derived. Our model, validated by extensive simulations, is able to accurately characterize VANET performance. Our analysis reveals intrinsic dependencies between cluster size, vehicle speed, traffic demand, and window size, as well as their impacts on the overall throughput and packet loss of the cluster. Performance evaluation results demonstrate the practical value of the proposed model in providing guidelines for VANET design and management.

EXISTING SYSTEM:

In empirical path loss models were developed in four different vehicle-to-vehicle environments, i.e., highway, rural, urban and suburban. In analysis of one-dimensional, an analytical model was proposed to investigate the connectivity of VANETs in the presence of Rayleigh, Rician and Weibull channels, from a queuing theoretic perspective. In one-hop broadcasting, analytical models were developed for broadcast efficiency and reliability in 802.11p for Rayleigh fading channels. In evaluation information propagation, the connectivity of information propagation was studied, focusing on packet loss rate, packet transmission distance and effective coverage range of road-side stations.

DISADVANTAGES OF EXISTING SYSTEM:

• Not always true in mobile vehicular environments
• Unable to provide complete evaluation

PROPOSED SYSTEM:

In this paper, we propose a comprehensive analytical model for VANET that incorporates MAC protocol operations, PHY layer wireless channel conditions, and the moving pattern of the vehicles. In doing so, the practical performance of a VANET cluster can be fully characterized. Specifically, we characterize the broadcast protocol of the MAC layer with a Markov chain, and design an idle state to capture unsaturated traffic conditions in practical VANETs. We also capture the influence of PHY layer fading channels in the model by deriving the joint distribution of the distance between every member vehicle and the CH. The mobility of the vehicles, to be specific, the speed and inter-vehicle distances, is reflected in the joint distance distribution. Calculating the important performance metrics of a VANET, such as packet loss and throughput, requires integrating the derived joint distance distributions, which makes closed-form expressions intractable.

ADVANTAGES OF PROPOSED SYSTEM:

• It can provide complete evaluation
• Increasing the throughput
• Reduce the delay

SYSTEM ARCHITECTURE:

BLOCK DIAGRAM:

SYSTEM REQUIREMENTS:

HARDWARE REQUIREMENTS:

• System :         Pentium IV 2.4 GHz.
• Hard Disk :         40 GB.
• Floppy Drive : 44 Mb.
• Monitor : 15 VGA Colour.
• Mouse :
• Ram : 512 Mb.

SOFTWARE REQUIREMENTS:

• Operating system : Windows XP/7/LINUX.
• Implementation : NS2
• NS2 Version : 2.28
• Front End : OTCL (Object Oriented Tool Command Language)
• Tool : Cygwin (To simulate in Windows OS)

REFERENCE:

Huixian Wang, Ren Ping Liu, Senior Member, IEEE, Wei Ni, Senior Member, IEEE, Wei Chen, and Iain B. Collings, Fellow, IEEE, “VANET Modeling and Clustering Design Under Practical Traffic, Channel and Mobility Conditions”, IEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 63, NO. 3, MARCH 2015.