LONDON — The encrypted, jam-resistant signal on Europe’s Galileo positioning, navigation and timing satellite constellation will be available to selected non-European allies that sign security agreements with the European Union (EU), according to the head of the agency managing the program.

The decision to offer Galileo’s Public Regulated Service (PRS) signal outside Europe coincides with Galileo managers’ decision to broaden PRS beyond its original military focus, said Carlo des Dorides, executive director of the European GNSS Agency, which is based in Prague.

The revised PRS market includes law enforcement and customs agencies, internal security forces, emergency response teams and operators of critical infrastructure including energy, transport and telecommunications facilities.

Galileo is Europe’s version of GPS. Four Galileo satellites have been launched and have begun testing PRS signal delivery. Two Galileo security-monitoring facilities — one in Britain, one in France — are under construction.

The full Galileo constellation is expected to have 30 satellites, including spares, in medium Earth orbit. European officials are pushing the Galileo contracting team to assure that 18 satellites are in service by the end of 2014.

Antonio Tajani, vice president of the European Commission, which owns Galileo, said here Dec. 3 that he is pushing the Galileo program to be able to provide initial services starting in late 2014. “We will not deviate from this goal, and we will not accept excuses,” Tajani said. “The message is that we need to get ready.”

The schedule has been made challenging by a software issue that is likely to delay the launch of future Galileo spacecraft.

In an interview during the European Space Solutions conference and exhibition, held here Dec. 3-5, des Dorides said an investigation into the software issue, which does not affect the four satellites in orbit, is expected to return its results by late December.

“The plan today is to have 18 [satellites] in orbit by the end of 2014, and a critical assessment of that plan is ongoing,” des Dorides said. “By the end of December we should know if this is an achievable objective. What is most important for us is to announce to the world, and to our user communities, that we are there.”

Galileo is likely to be the last of the four global positioning, navigation and timing constellations to be deployed in orbit, after the United States’ GPS, Russia’s Glonass and China’s Beidou Compass. For des Dorides, this is not the critical point.

“We will be a bit later, and that is why we need to focus on our competitive advantage, which is that we are committing to a certain performance level,” he said. “None of the other systems offer this guarantee. Yes, having China’s system in service matters. They have quite a large internal market, and the economies of scale are there. But again, our competitive advantage remains just as valid.”

In addition to an open service to be available, free of charge, to all users, Galileo features a commercial service for demanding sectors such as airlines for positioning and navigation and financial institutions for timing. These users will pay a fee and in return will receive guarantees of Galileo performance.

Galileo’s PRS resembles the military, or M-code, signals being placed on the GPS constellation. M-code security modules will be provided to U.S. NATO allies and perhaps other nations, a fact that has complicated the argument for PRS in some NATO governments. The British military, for example, has said its use of M-code is enough, and that it does not plan to use PRS.

But the heated debate about the nature of PRS appears to have abated. The British government, which in the past has questioned the need for PRS’s existence among Galileo’s core service offerings, has softened its position and is now, with France, among Europe’s leaders in preparing for PRS’s arrival.

Under the terms of the European Union regulations for Galileo, each nation that wishes to use PRS must first create a “Competent PRS Authority” that determines who will have access to the signal, and who will build PRS receivers and security modules.

Not all 27 EU nations need to establish such an authority; some nations may wish to outsource the service, much as they will outsource the manufacturing of PRS hardware.

But whatever the arrangement among the 27 EU member governments, Galileo PRS security modules will be manufactured exclusively by EU companies, des Dorides said.

One European industry official said this policy is equivalent to the U.S. government procedure with respect to the GPS M-code.

The United States and Europe have been cooperating on their respective satellite navigation constellations for nearly a decade, ever since Europe agreed not to place its PRS signal on a piece of the radio spectrum that the U.S. Air Force had planned for the M-code.

The U.S. government said the European plan would compromise regional navigation warfare in the future in which a U.S. adversary was using Galileo PRS signals. If PRS and M-code shared frequencies, jamming one would jam them both.

Europe ceded the point and moved PRS off of the M-code frequencies. U.S. and European satellite navigation experts now meet regularly, most recently in late November in Prague, to advance cooperation and system interoperability.

U.S. and European Union representatives are also part of the International Committee on Global Navigation Satellite Systems, which has been in place since 2007 and includes Russia, whose Glonass constellation has returned to full global service; and China, whose Beidou Compass constellation is now being deployed in orbit.

European Union and Chinese government officials are scheduled to meet in Paris this month to discuss China’s plans to place the Compass government-only signal — China’s PRS and M-code equivalent — on spectrum overlapping the PRS spectrum.

Nothing in the international radio frequency regulations prevents this. China is now well into fielding its constellation, and it is unclear what Europe could offer to cause the Chinese to change their frequency choice. As Europe did before it, China has argued that there is not that much spectrum available for these services, and finding alternative frequencies would be difficult.

 European officials have not been clear on whether a Chinese decision to keep their secure service where it is would compromise Galileo in any serious way, forcing system managers to change the signal structure on future satellites.

Des Dorides said his office is not involved in the political-level negotiations with other navigation system operators. But he said he fully expects the NATO allies to equip their forces with dual-mode receivers carrying PRS and M-code security modules.

“I cannot imagine a situation where we don’t have dual-mode receivers compatible with M-code and PRS,” he said. “Defense users are obviously going in that direction. Regulation does not prevent this from happening, and I don’t see how NATO would not have dual-mode receivers. The only issue is affordability — something we have to work on, and invest in.”

The European GNSS Agency has tentatively concluded, in a survey of future PRS users, that 250,000-300,000 PRS-enabled receivers could be in the market by sometime in the middle of the next decade.

That assumes that the full Galileo constellation is launched and operational by around 2017.

Peter B. de Selding was the Paris Bureau Chief for SpaceNews.