February 9, 2006:
The U.S. Department of Defense has 135,000 portable GPS receivers in service, plus many more embedded in weapons and equipment. There are two models of these portable (hand-held) GPS receivers; 100,000 older (from the early 1990s) PLGR models, and 35,000 new DAGR models. The $2,300 DAGR (Defense Advanced Global Positioning System Receiver) weighs nearly a pound (15 ounces), but is small enough (6 3/8" x 3 7/16" x 1 9/16") to fit into a standard two-clip ammo pouch. DAGR can get its first position fix within 60 seconds, and can run continuously for twelve hours on its battery. There are a number of useful accessories, including an anti-jamming device, a more powerful antenna and external power cables. DAGR has one major advantage over commercial GPS receivers, it can use the Precise Positioning Service (PPS) signal. PPS allows users to operate reliably when someone is trying to jam GPS signals. DAGR also has the most popular features found in commercial GPS receivers, and can easily have its software updated. DAGR has a 1.7x2.3 inch display, and can survive submersion into nearly 40 inches of water. The display is the major advantage of DAGR, as it can display more useful information, in map form, about where the troops are, and where they are going. The Department of Defense has 250,000 DAGRs on order, and will keep the older PLGRs in service for up to five years. The PLGRs are useful for vehicles, and the army wants to put a GPS unit (a PLGR will do) in every vehicle it has, especially the ones operating overseas. Many troops will buy their own personal GPS receivers, as these are available, in many commercial models, for under a hundred dollars.
The next generation GPS device is being designed, sort of. The DAGRs are expected to last for at least another five years. But with GPS being built into so many things, it's difficult to know what features a special military GPS would have to have to justify the cost. GPS receivers are becoming a feature, not a separate piece of equipment.