Data Acquisition Frequency Of Probe Vehicle And Accuracy Analysis Of Map Matching

Congestion has become increasingly serious problem on a global scale. Traffic congestion not only led to air pollution, noise pollution, energy waste and traffic accidents, but also resulted in reducing efficiency of people’s daily life, deteriorating the living environment and lowering the city attractions. At present, the best way to solve the traffic congestion problem is based on floating car traffic information service system, which issued the related information floating car and then estimate the real-time road traffic conditions. Travelers based on the information to choose the best travel routes and times. As a result, road to ease traffic pressure. So traffic delays and congestion reduced to the lowest level.This article aims to address the data acquisition strategy of TIS base on probe vehicle. High frequency acquisition will produce more data traffic, thus will put great pressure on data sending device and the server. Low frequency acquisition will influence map matching accuracy greatly, cannot get an effective result. We need to find the best data acquisition strategy.Be specific to the road network of Shenzhen, we research the influence of floating car data acquisition period on map matching accuracy, analyze the common error types of map matching and point out the types of error can be effectively improved by high frequency acquisition. According to accuracy analysis of map matching, map matching accuracy can be significantly improved when floating car data acquisition period shortened from 30 sec to 21 sec. However, further shortening the acquisition period have no significantly improvement effect on map matching accuracy. According to error analysis of map matching, high frequency acquisition can effectively improve the map matching error caused by U-turn and heading misjudgment. But map matching error caused by paralleled road and tunnel cannot be improved. The latter two types are the main cause of map matching error.The data acquisition strategy research specific to the road network of Shenzhen shows that under the current condition of GPS precision and algorithm, data acquisition period at 20 s is the best data acquisition strategy, which are acceptable on both data traffic and map matching accuracy.