MAP-MATCHING WITH COMPETING SENSORY POSITIONS

A method, and corresponding system, of map-matching uses a first trend of position vectors (207, 215, 221, 229, 235, and 245) provided by a first position sensory system, and a second trend of position vectors (203, 211, 217, 225, and 231) provided by a redundant position sensory system. These sensory systems are preferably mounted on a vehicle but also may be a part of a hand held guidance device. The first position sensory system is preferably a GPS receiver (305) based system, and the second position sensory system is preferably a dead-reckoning sensory system, based on a compass (307) and an odometer (309). The first trend of position vectors (207, 215, 221, 229, 235, and 245) and the second trend of position vectors (203, 211, 217, 225, and 231) are compared to a trend of position vectors (212, 287, 289, 291, and 293) based on a map reference (303). A reference position vector (205, 213, 219, 227, 233, 239, 243, 246, and 249) is updated based on a matching of either or both of the first and second trends of position vectors to the trend of road segment position vectors based on the map reference. Further, one or more of the non-matching sensory system(s), or an estimated position vector associated with the non-matching sensory system(s), may be corrected influenced based on the updated reference position vector.