METHOD FOR IDENTIFYING HIGHWAY ACCESS RAMPS FOR ROUTE CALCULATION IN A VEHICLE NAVIGATION SYSTEM

摘要

A method for identifying highway access ramps in a database medium for use as locations for route calculation. Initially, first road segments which belong to a highway and which are connected to at least one access ramp are identified. The first road segments are sorted according to the highway to which they belong. A highway direction is determined for each first road segment. The first road segments belonging to a first highway are sorted according to highway direction. The first road segments belonging to the first highway and of each highway direction are sorted according to position, thereby forming a highway segment list for each direction of the first highway. Highway access ramps are identified for each first road segment in the highway segment list. The locations for the highway access ramps are stored in the database medium. Highway access ramps are identified in this manner for each highway in the database medium. A method and apparatus for determining a route from a starting vehicle position to a destination using a vehicle navigation system are also provided.