DOD charts GPS path
- By Paula Shaki Trimble
- Apr 03, 2000
The Defense Department is in the early stages of setting a new course for
its satellite-based Global Positioning System, DOD officials said last week.
And the Transportation Department and other civilian GPS users are asking
for more of a say in the process.
DOD is gathering system architecture requirements for what it calls
GPS 3, a 30-year modernization project of the system that provides accurate
positioning and timing information used by military and civilian organizations
for navigation and other applications.
GPS currently operates with a minimum of 24 satellites. The study could
lead to new configurations of the satellites, an increase in the number
of satellites or modifications to the signals they broadcast. The changes
would provide users with increased positioning accuracy, more access to
the signals and higher signal power.
"We are on the fast track to GPS requirements," said Ray Swider, assistant
for GPS, positioning and navigation at DOD, at a meeting of the U.S. Coast
Guard-sponsored Civil GPS Service Interface Committee last week in Fairfax,
Earlier this year, the Air Force indicated it would not exercise options
with Boeing Co. for up to 33 new GPS Block 2F satellites, which were designed
to add two new signals for use by civilian agencies, as well as new military
signals. Six of those satellites already have been purchased.
"One of the reasons for entertaining GPS 3 rather than continuing Block
2F was to give time to assess future needs," Swider said. "We want to use
a clean sheet of paper to look at the architecture."
DOD plans to award three study contracts in 2001. The studies will assess
satellite architecture, ground infrastructure, ways to optimize the constellation,
augmentation systems and other platforms for navigation payloads, said Lt.
Col. Bill Kaneshiro, chief of systems architecture and engineering at the
GPS Joint Program Office at Los Angeles Air Force Base. They also will look
at ways to upgrade the satellites in orbit.
"We want to fly satellites that allow technological changes and evolve
to meet user needs," Kaneshiro said.
DOD, which originally created GPS, is the lead agency on GPS 3, but
civilian users of satellite navigation want to ensure their needs are accounted
for as DOD defines its requirements, which should be complete next summer,
DOT and other civilian agencies are concerned because DOD controls the
funding available to upgrade the GPS system. DOT failed to secure $17 million
in its 2000 budget request to upgrade those GPS satellites that provide
signals available to nonmilitary users. For fiscal 2001, the Clinton administration
chose to include the civilian modernization in DOD's budget request.
But the administration shares the civilian agencies' concerns. The Office
of Management and Budget has asked DOD to sign a "memorandum of understanding"
with DOT. The memo, which should be complete in about three weeks, is the
mechanism for ensuring civilian requirements are included in the GPS 3 studies,
Swider said. Also, the Interagency GPS Executive Board, sponsored by the
Commerce Department, is responsible for articulating the civilian community's
future requirements for GPS.