Requirements for the Map in a Map-Matching Guidance System

Automatic map-matchers, or terrain-sensing guidance systems, have been developed for a wide range of applications, including aircraft navigation, cruise missile guidance, and steering corrections in the terminal phase of ballistic missile flight. Common to all terrain-sensing guidance concepts is comparison of the output of a live sensor to a prestored map in which the location of the target is known. While intensive efforts have gone into development of sensor and correlation technology for these systems, an equally important element in system viability is the accuracy and adequacy of the stored map and the data base from which it is produced. Indeed, the overall guidance accuracy can be no better than certain characteristics of the map used. This paper is intended to serve as an unclassified introduction to the kinds of technology required to generate such maps, as well as the accuracy requirements which must be placed on them.