November 6, 2007 The fourth in a series of eight modernized Global Positioning System (GPS) satellites that will deliver new capabilities to military and civilian users has been declared fully operational.

Launched from Cape Canaveral October 17, the satellite was given the all clear after an on-orbit checkout by a combined U.S. Air Force/Lockheed Martin team.

Part of Global Positioning System Block IIR (GPS IIR-M), the new GPS IIR-17M satellite features a modernized antenna panel that provides increased signal power to receivers on the ground, two new military signals for improved accuracy, enhanced encryption and anti-jamming capabilities for the military, and a second civil signal that will provide users with an open access signal on a different frequency.

The satellite joins three IIR-M satellites and 12 other operational Block IIR satellites within the current 28-spacecraft constellation.

The fifth GPS IIR-M satellite is scheduled for launch on December 20 from Cape Canaveral, with the three remaining GPS IIR-M satellites to launch next year. One of these satellites will include a new demonstration payload that will temporarily transmit a third civil signal, known as L5.

Contract will be also awarded for the next-generation Global Positioning System, GPS Block III, in early 2008. This program will improve position, navigation, and timing services for the warfighter and civil users and provide advanced anti-jam capabilities yielding improved system security, accuracy and reliability.

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