NOORDWIJK, Netherlands — European government officials say China’s Beidou/Compass global satellite navigation project poses both technical and security-related threats to Europe’s Galileo system.

They said they are becoming frustrated by China’s refusal to discuss the issues in a straightforward way as the deadline approaches for Europe to set in stone Galileo’s signal specifications.

At briefings here March 5 at the Estec technology center of the European Space Agency (ESA), officials said they hope to make headway on the Beidou/Compass issues in talks with Chinese officials in April.

A Chinese delegation led by JianlinCao, China’s vice minister for science and technology, is scheduled to visit Europe the week of April 21.

European government officials said they have only until this summer, at the latest, to commit to a specific Galileo signal structure, which they might wish to modify depending on how China’s Beidou/Compass project develops.

“We are trying to keep all our options open but there is a point where you have to freeze the specifications,” said Paul Verhoef, head of the Galileo unit at the European Commission, which is now financing all of Galileo’s development. “There shouldn’t be any worry about the Chinese system. But the Chinese have been saying Compass is a military system only, and more recently they have been saying it is also for commercial use, for commercial applications. The issue with the Chinese is: We want good interoperability and compatibility between them and us.”

The European Commission is hiring ESA to manage Galileo contracts, with bid requests expected to be sent to industry by July and final contracts to be signed in December. One European government official said Galileo’s technical design, including the signal structure of its Public Regulated Service (PRS) – the equivalent to the U.S. GPS system’s military signal – must be fixed in stone when the industrial bids are solicited.

As described in China’s frequency registrations with the International Telecommunication Union outline, China plans to expand the current Beidou/Compass navigation system from a regional effort using geostationary satellites to a global effort including 30 medium Earth orbiting spacecraft.

It remains unclear when China will deploy the global system. China launched one Beidou/Compass satellite in April 2007 to reserve its frequencies with international regulators, but the status of the full constellation is unknown.

“They have put up one satellite in medium Earth orbit that does ‘Beep, beep’ and nothing else,” said Giuseppe Viriglio, ESA’s navigation director. “As a global system, Compass does not seem to be in development yet.”

But as it stands now, Beidou/Compass poses two types of problems for Europe and for managers of the U.S. GPS system.

European government officials say the global Beidou/Compass would interfere with Galileo’s signals, and that negotiations are needed immediately to determine how this can be avoided.

The second problem with Beidou/Compass is strategic in nature. Originally described as an all-military system, it proposes to use frequencies that are planned for Galileo’s PRS, and for the GPS military code.

Such frequency overlay does not pose a technical interference issue, but it does mean that in an emergency, European and U.S. officials could not jam the Chinese signal without also jamming their own encrypted, security-related signals as well.

One government official said the European Commission hopes to demonstrate to China that “the problem is symmetrical – poses the same difficulties for Chinese authorities if there is an emergency in China.

“If we have a security alert in Europe that relates to, say, a nuclear power plant, we would want to jam non-PRS signals,” this official said. “We couldn’t do this if Beidou/Compass partially overlays our PRS. But Chinese officials would have the same problem in the event of a security alert in China.”

European officials said privately that the problem for U.S. GPS managers is even more complicated because of the potential for military friction between China and the United States in East Asia, and particularly in the Taiwan Straight. “That tends to make frequency coordination a bit more touchy, which is not a problem we have,” one European government official said.

U.S. government officials, led by the U.S. State Department, continue to discuss Beidou/Compass issues with the Chinese but have said that, like the European Commission, the United States is not certain where the Chinese are headed with their system.

Several officials said a big problem in discussing Beidou/Compass is determining who in China has the authority to make decisions about it among the various government agencies with satellite-navigation roles.

At the Munich Satellite Navigation Summit Feb. 20, a Chinese government official said China intends to become an active participant in the international group of nations with satellite positioning, navigation and timing systems.

The group, called the International Committee on GNSS – for Global Navigation Satellite System – has met twice, most recently in September in Bangalore, India – and plans a third meeting in December in Pasadena, Calif.

“Today our frequencies for Compass are not fixed,” said JingGuifei, head of the National Remote Sensing Center of China, during a Feb. 20 interview following the summit. “We launched Compass M-1 in medium Earth orbit to secure our frequency filings and to validate the technology for future suppliers. But we want to coordinate with GPS, Galileo and [Russia’s] Glonass systems.”