Efficient location referencing method

US8626438B2 · kind B2 · utility

Assignee

• TomTom International B.V. · NL

Inventors

• Lars Petzold · Berlin, DE
• Ralf-Peter Schaefer · Berlin, DE
• Sven Baselau · Berlin, DE

Key dates

• Filing date: Jun 29, 2009
• Grant date: Jan 7, 2014
• Expiry date: Sep 10, 2030

Classification

• Technology area (CPC G): Physics
• CPC primary: G09B29/106
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A efficient method of encoding a continuous path within a road network in which the path to be encoded is expressible as a path list of lines and/or segments existing in a digital map and consecutively ordered. The method comprises the steps of: (i) storing a start position in a route search list; (ii) determining a path from a start node of the start position and including said start position to an end node of the last line or segment in the path list within said digital map, said path being determined according to a shortest path algorithm; (iii) comparing the shortest path so determined to the path list, and identifying at least one deviation line or segment being part of the path list and having a start node representative of an intersection in said digital map but not being the line or segment first appearing in said path list, and if such deviation line or segment does not terminate at the end node of the last line or segment appearing in the path list, repeating step (i) using said deviation line or segment; and (iv) storing the last line or segment in the path list in said route search list if not already stored.