The U.S. Defense Department has probably been selectively jamming signals from the Global Positioning System (GPS) in Afghanistan since the start of the air campaign, according to nonmilitary GPS experts.
The Pentagon is planning to muddle satellite navigation signals to prepare themselves for potential loss of the Global Positioning System (GPS). Designed to provide precise longitudinal and latitudinal coordinates to anything on land, at sea or in the air that has a GPS receiver, the satellite system has become increasingly critical to military operations since its introduction in the early 1990s.