Navigation system for vehicles including present position calculating means

摘要

In order to calculate the traveling distance and heading of a vehicle in highly accurate fashion, a navigation system is provided with a distance sensor for outputting pulses in proportion to rotation of a wheel, a GPS receiving unit for calculating vehicle speed by GPS reception, acquisition unit for acquiring the number of pulses at the same time as GPS reception, distance correction coefficient calculating unit for calculating GPS traveling distance from the GPS-reception vehicle speed and a time difference between any two points, and calculating a distance correction coefficient from the GPS traveling distance and a pulse difference between two points, and present position calculating unit for calculating present position based upon a corrected distance correction coefficient.