发明名称 Method and system for route calculation that avoids railroad crossings
摘要 A navigation system provides information about railroad crossing locations. A geographic database used by the navigation system includes data that indicate whether an at-grade railroad crossing is located along a road segment. Using this information, a route calculation function in the navigation system calculates a route to a destination that avoids road segments that have at-grade railroad crossings. In this way, the delays associated with waiting for a train to cross a road are avoided.
申请公布号 US6751549(B1) 申请公布日期 2004.06.15
申请号 US20020053257 申请日期 2002.01.17
申请人 NAVIGATION TECHNOLOGIES CORPORATION 发明人 KOZAK FRANK J.
分类号 G01C21/34;(IPC1-7):G01C21/30 主分类号 G01C21/34
代理机构 代理人
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