Research On Adaptive Transmission Mechanism Of Beacon Messages In Vehicle Ad Hoc Network

Vehicle ad hoc network is one of the key technologies in intelligent transportation systems.It has developed rapidly in recent years and can play a vital role in traffic safety,in-vehicle entertainment and other services in the future.The foundation to support these applications is the beacon message,all vehicle nodes and roadside equipment nodes transmit messages through periodic beacon message transmission.However,the vehicle ad hoc network has the characteristics of large changes in vehicle node density,rapid changes in wireless network topology,and diverse changes in wireless channel communication quality,which makes it difficult to guarantee real-time and reliable beacon message transmission,which directly affects the quality of some applications such as traffic safety.In this regard,this article has conducted an in-depth study on the beacon message transmission mechanism in the vehicle ad hoc network.The main contents are as follows:1.The vehicle transmits the location and motion status of neighboring vehicles through beacon messages,and predicts the location of neighboring vehicles for a period of time in the future,thereby judging whether the vehicle is likely to have an accident and warning the driver.However,in the vehicle ad hoc network,the speed of the vehicle is very fast.In the case of a poor network environment,the vehicle position transmitted by the beacon message has a large error with the actual position.The traditional solution is to use linear prediction to predict the position of the vehicle in advance,but this method has a very large prediction error when the vehicle is turning,which is likely to cause accidents.For this reason,this paper proposes a linear combination model to predict the position of the vehicle,which greatly reduces the position prediction error when the vehicle is turning.2.Define the driving stability of the vehicle according to the prediction error of the vehicle’s position.The one with large error is the one with poor driving stability,and vice versa,the one with good stability.An adaptive beacon information broadcast period algorithm based on vehicle driving stability is proposed,which sets a threshold for the beacon message broadcast period according to the channel load capacity,reduces the period of the beacon message broadcast by vehicles with poor driving stability,and increases the period during which vehicles with good driving stability broadcast beacon messages.Experimental results show that the algorithm can effectively reduce communication delay and packet loss rate.3.Vehicles with larger predicted position errors are generally considered to be more dangerous.Therefore,based on the previous algorithm,the main effects of signal fading and channel contention are analyzed,and an adaptive beacon based on vehicle position prediction errors is proposed.Message transmission power control algorithm,and three different channel models are used to analyze the performance of the algorithm.Experimental results show that the algorithm can effectively increase the data transmission rate and ensure the safe and effective transmission of information.