| 摘要 |
A method for determining the existence of an underpass (21) in a digital map by observing probe data is provided. The method includes providing a digital map having at least two road segments (18, 20) and reporting data from a plurality of probe traces traveling along the at least two roads segment (18, 20). Further, analyzing the reported data for dilution of precision (DOP) values. Then, inferring the existence of an underpass (21) along one (18) of the at least two road segments (18, 20) if the DOP values suddenly decrease from a substantially constant value to a decreased value and then suddenly return to the substantially constant value. |
