GPS shutdown to occur only under remarkable circumstances

A national policy President Bush authorized last month that establishes guidance and implementation actions for space-based global positioning, navigation and timing systems in the event of a major terrorist attack doesn’t appear to threaten the interests of contractors and other civilian users of the technology, according to the Defense Department.

A Dec. 15 Associated Press article reported Bush ordered plans for temporarily disabling the U.S. GPS network during a national crisis to prevent terrorists from using the technology. While a Defense Department fact sheet on the policy acknowledges “adversaries, including enemy military forces and terrorist groups,” could use the GPS systems, the primary goal of the government directive was to ensure the United States maintains and improves the positioning technology.

The White House said any shutdown of the GPS system within parts of the United States would come under only the most remarkable circumstances. The GPS system was kept active during the aftermath of the Sept. 11 attacks.

“If something happens to cause the government to shut down the entire GPS system, there are bigger problems to worry about,” said J. Dennis House, senior advertising and marketing manager with Topcon Positioning Systems, which manufactures GPS systems for construction purposes.

House said Topcon’s customers would still have access to some positioning satellites in the event of a GPS shutdown because the company’s products also use the Russian Glonass system, basically an equivalent of the U.S. system. But, he adds, customers could experience less-than-perfect results when relying solely upon the Glonass system because it only features 14 satellites, compared to the United State’s 30.

Lea Ann McNabb, a spokeswoman for Trimble Navigation, also dismissed concerns the government would shut down the entire GPS network. She said the company, which helped supply the U.S. military with GPS receivers during the Persian Gulf conflict, hasn’t considered the possibility of such an action.

The GPS system is owned and operated by the U.S. military. The military can disable the system by reducing the accuracy of the signals available to non-military users. The Defense Department could block civilian signals while maintaining encrypted military signals should a need arise.

The right to block or deny service to civilian users of GPS systems has been in place since the technology was made available to that audience in the early ’80s. Any disruption of service would be localized and would not affect the entire system, according to the White House.

The new policy on GPS technology also establishes a permanent national executive committee for space-based positioning, navigation and timing systems. The deputy secretaries of the Defense and Transportation departments will co-chair the committee, and committee members will include officials from the departments of State, Commerce and Homeland Security, the Joint Chiefs of Staff, NASA and other agencies as needed. This committee will make recommendations concerning GPS to its departments and agencies, and to the president.

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Patrick Beeson can be contacted at pbeeson@randallpub.com.