Mini-map-matching for navigation systems

摘要

The present invention uses a map database which is created with the view of optimization in terms of size and complexity, so that it can be easily embedded into a navigation chip. The optimized map database is referred to as a “mini-map” database. The mini-map database easily integrates with the position calculation routine. The algorithm for position calculation includes a map-matching component, which is referred to as the “mini-map-matching” (MMM) algorithm, which is implemented on the navigation chip. Application of the present invention includes any navigation system for vehicles and/or pedestrians. The navigation system may include an inertial sensor, such as a dead-reckoning (DR) sensor, for further improvement in calculated positional accuracy when satellite signals are degraded due to environmental factors.

主权项

1. A method implemented by a computer comprising:
identifying a geographic area where signals from a navigation satellite system are degraded; selecting the geographic area as one of a plurality of selected geographic areas for which a respective reduced set of map data is to be included in an embedded map database; identifying regular-sized map data corresponding to the geographic area; identifying superfluous points in the regular-sized map data that have little or no impact on navigation performance; removing the identified superfluous points from the regular-sized map data to produce the respective reduced set of map data for the geographic area, wherein the steps of identifying superfluous points and removing the identified superfluous points are iteratively performed in accordance with anon-volatile memory size of a navigation chip into which the embedded map database is to be embedded; and creating, by the computer, the embedded map database using the reduced set of map data.