Technical problems are degrading the accuracy of signals from the last GPS satellite launched by the Pentagon, sparking concerns among U.S. military and aerospace industry officials that the next generation of the widely used satellites could face similar troubles.

The GPS system, which serves both military and civilian users, provides precise time and location coordinates for everything from military missile launches and "smart" bombs to automated bank-teller machines to aircraft, ships and everyday vehicles. The Lockheed satellite is the first to include a new civilian frequency -- dubbed L5 -- designed for, among other things, use by future nationwide air-traffic control systems. But that signal, part of test package, apparently is interfering with other signals from the satellite and reducing their accuracy, according to industry and Air Force officials. The degraded signals are accurate only to about 20 feet, versus about two feet for typical GPS signals, industry officials said.