Terrain aided navigation: current status, techniques for flat terrain and reference data requirements

It is pointed out that terrain referenced navigation (TRN) techniques are now well established as effective position-fixing systems suitable for use in manned and unmanned vehicles. The SPARTAN TRN technique, which has been selected for the UK Tornado GR4 update, provides accurate navigation with rapid initial capture without recourse to an initialization mode. An overview of the SPARTAN technique is provided, and techniques for improving navigation performance over very flat terrain are described. The benefits of the terrain characteristic matching techniques are outlined, and a summary of integrated navigation system performance is given. Terrain-aided systems require appropriate reference databases. The availability of the data and its suitability are discussed. The need for careful consideration of database quality and registration when terrain aided systems are being designed is indicated