Data transmission strategy of probe vehicle in floating car traffic monitoring

The floating car data (FCD) method is an example of the applications of the Intelligent Transportation Systems (ITS) where the traffic data are provided by means of the information and communication technology. In the FCD method, the traffic data are collected, manipulated, and transmitted by probe vehicles via a wireless network to a designated server where the data are stored, manipulated, and displayed in conjunction with a digital map. The method is capable to provide near real-time traffic data but its performance strongly and mainly depends on the reliability of the wireless network. In this work, the traffic data transmission strategy in the FCD method is discussed and its effect to the timeliness of the traffic data is described. As the results, it is found that when the data transmission strategy is not properly designed, a delay in a transmitted packet of data directly affects and intensifies the subsequent data transmission. We propose a transmission strategy to minimize the time delay and experimentally demonstrate that the strategy can reduce the time delay significantly.