Research And Design Of Dedicated Communication Protocols Based On IEEE802.11

With the development and advancement of our society, problems in traffic system have drawn more and more attentions. Big progresses in computer technology and communication technology would turn our future traffic system into a networked one which would be highly intelligent.Intelligent Transportation System (ITS) is an integrated terrestrial transportation sytem which incorporates advanced computer technology and communication technology. It benefits from superb security and mobile management while imposing less harmfull effects on the environments.Currently, the DSRC (Dedicated Short Range Communication) has been a great hit in the research fields of both transportation and communication. It’s a most prospective wireless solution for our future ITS, including V2I (Vehicle to Infrastructure) and V2V(Vehicle to Vehicle). The core part of DSRC is the WAVE (Wirelss Access in Vehicular Environments) procotol stack mostly defined by IEEE. This WAVE protocol stack in mainly based on IEEE802.11while introducing some new protocols that are tailored for wireless vehicular communications, such as the IEEE1609.4for multi-channel operations of MAC layer and the IEEE1609.3as a light-weighted protocol working in the transmporation and network layer.Howerver, the current IEEE802.11p/1609.4hierarchy suffers from many deficiencies. In this thesis, the performance of the existing IEEE802.11p/1609.4is thoroughly studied and a novel location based channel congestion control scheme is designed and proposed to improve the performance especially for urban V2I scenarios.In the remaining part of this thesis, design and implementation of the IEEE1609.3protocol is presented. Thorough analysis to the protol is made and the core functionalities of this protocol is designed and implemented in Linux operation system. Successful data sending and receiving is achieved which are conformed to the standard. The core primitives, the management entitiy and other necessary components for this protocol are also implemented. User applications and tests were also made to demonstrate the built system.