Research On Multi-hop Broadcast Based On Real-Time Restriction In VANET

With the unprecedented rapid development of contemporary high-tech such as information,computer and data communication,Intelligent transport System(ITS)has become the most popular technology in current vehicle engineering.lt integrates a variety of high and new technologies in the current society into a complete system and effectively uses it in the management of the entire road traffic to integrate and clear the flow of traffic.At the same time,it focuses on the research and establishment of a broader,More real-time and more accurate and efficient comprehensive management and transport system.And Vehicular Ad hoc Networks(VANET)which as a special network for road traffic plays a crucial role in supporting the operation of ITS.The current traffic environment tends to be more and more informational which provides the possibility for the realization of VANET.Thanks to the current development of vehicle technology,almost any vehicle is equipped with communications equipment and sensing equipment,vehicles can easily obtain live data including speed,direction,position.And inform the surrounding vehicles of the real-time data through the communication equipment,then vehicles ahead of time to make decisions to avoid collision and other safety-related accidents.Due to the dynamic changes of network topology,poor channel quality and limited communication range in VANET,In the realistic traffic environment,the vehicle node obtains the broadcast beacon data obtained from the periphery not only exist the overdue data which get certain interval between the time when the data is received by the node and the time when the data is generated,but also exist many distortion data which get some error between the received data and the real data affected by the traffic environment.In this paper,in order to solve the problem of overdue data,after combined with the characteristics of traffic in the real traffic conditions,we design MBBRT,Multi-hop broadcast based on real-time in VANET.This algorithm includes real-time data estimation,weight mapping,relay node selection and timeout retransmission.According to the current received data,using the difference estimation method to estimate the current real-time data,then combined with the different prediction result data design weighting algorithm to weight each node mapping values.In the last,we use overtime retransmission mechanism to ensure the effective transmission of data packets.In addition,addresses the issue of poor performance due to error data,based on the above research results,we design MBBLA,Multi-Hop Broadcast Protocol in VANET Based on Fuzzy Logic.Adopting the fuzzy logic processing mechanism to deal with the traffic data to improve the tolerance of the broadcast mechanism to the error data.The algorithm mainly includes real-time data estimation,directional transmission and alternate forwarding mechanism.First,use real-time data estimation to avoid overdue data affect on the algorithm performance,then use fuzzy logic process the estimated the predicted data,and choose the relay node to transmission data packet.The process includes calculating the input factor,fuzzy calculation,rule matching and precision calculation.At last,we also use candidate forwarding mechanism to reduce the probability of packet loss.Simulation results show that the proposed algorithm provides improvement on fault tolerance and the properties of real-time than related algorithms.