target-findinS and horning devices devel-oped. for conventional mrnitions night be used. 95. To inprove long-range navigation, the i.nertial guidance systems vhich have long been used need to be supplenented by internittent, precise position in.forroation. This can be provid.ed. by a set of satellites in geostationary orbit as il-lustrated" e.g., by the United States Globa^l Positioning Systen (CpS) or Navigation System using Tine AnaI nange (NAVSIAR). For cruise missiles al]d. other low-flying vehicles, it is possible to scan the ground bel-ow ard. compare the results ith d.ata fiLed. in the computer memoxy of the vehicle. This coul-d be done by neasuring only the verbical profile of the Sround (e.g., Terrain Contour I4atching or TERCOM ) or by scanning some of its area properties (e.g' " Map Matching or IvM). 0f these techniques " GPS or NAVSTAI is said. to have been established but not depl-oyed, and there are reports of some technical difficulties regarding actual deploynent. TERC0M is weff advanced and MM still- experimental ' 97. For troming a weapon on the target, a m.mbex of sensols have been deveLopeal to govern the operations of steering mechanisms in the proJectile. These horning systens i.nclude a variety of radar, infrared and 18.ser devices' Sone of them coul,d. be ad.apted for use within strategic vehicles; others nay be used to enhaJrc e the accuracy of various tactical nuclear veapons ' To lrhat extent the nucl"ear- veapon States have already inplenented such options is not known, although nuclear-wespon States have not d.epfoyed guidsJrce systens for re-entry vehicles from ballistic missiLes , 98, Ad.vances in propulsion technology are also highly relevant for the evol"ution of nuclear forces, the nost recent exanple being the d evelopment of the cruise nissile. Jet-plopelfedo aerod.lmanic nissiles were first introduced in the Second
**Analysis**
The text appears to discuss the development and advancement of military technology, specifically in the areas of navigation, guidance systems, and homing devices for nuclear weapons and cruise missiles. The text mentions various technologies such as GPS, TERCOM, and Map Matching, which are all related to military applications. The language used is technical and jargon-heavy, suggesting a focus on scientific and technological advancements rather than social or economic issues.

**Category**
Science and technology