The Research of Improved Pre-fetch Strategy of the Vehicle Terminal Based on the Central Navigation

In order to improve the utilization of the map data unit and the network bandwidth when displaying on the terminal system, an improved strategy is putted forward based on the existing map data pre-fetch strategy. This strategy considers the road network information and the current direction angle when the system pre-fetches map data. Tests show that the improved strategy can not only meet the real-time demand of displaying map data, but also improve the hit ratio of the unit efficiently.