An analysis of GPS sampling rates required in travel time estimation

With an emergence of vehicular ad hoc networks, it is highly likely that in the near future vehicles on the road will be used as mobile probes for collecting and distributing traffic information such as the travel time. Generally, the travel time on a road section can be estimated from the global positioning data collected by a mobile probe. The more frequent the positioning data are collected or sampled, the more accurate the travel time estimation is. However, the accuracy comes at the expense of a large storage space for keeping the data. In addition, in some systems where a mobile probe needs to send its positioning data to a server or other vehicles in real-time, using an overly high sampling rate can waste the radio channel bandwidth unnecessarily since excessive amount of data will be transmitted. In this paper, we determine the minimum collection rate of positioning data required to achieve the desired level of travel time estimation accuracy.