terrainreferenced
Terrain-referenced navigation is a method of determining a vehicle's position by matching observations of the surrounding landscape to a stored digital terrain model. The system uses sensors such as radar mapping equipment, radar altimeters, or LIDAR to measure terrain features and elevation, and a processor to correlate these observations with a terrain database, usually in combination with an inertial navigation system.
Operation involves measuring the terrain profile along the vehicle’s path, converting it into a feature representation,
Typical components include a digital terrain database, terrain observation sensors, a correlator or matching processor, and
Applications have been broad in aviation, including military aircraft and helicopters operating in contested airspace, with
Advantages include resistance to jamming and spoofing, wide-area coverage, and the ability to operate where GNSS
Development began in the mid-20th century and has evolved with digital terrain models and enhanced correlators;