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SATELLITE navigation systems are integral to everyday life, an invisible utility that underpins not just how we get around, but also our power supplies and communications. While the world once shared the US Global Positioning System (GPS), rival satellites are now becoming fully operational, and a political battle is under way in orbit.

鈥淩eliable position and timing are strategically important resources,鈥� says John Pottle, director of the Royal Institute of Navigation in London. 鈥淗aving control over them is important in the same way as having secure energy supplies or access to medicines.鈥�

The first GPS satellite was launched in 1978, but the full array of 24 required for continuous global coverage didn鈥檛 go live until 1993. It was originally intended as a military system, and still broadcasts encrypted signals exclusively for military users as well as the signals civilians use.

Now it is getting an upgrade. Last month, the satellites is operational. Ten of these, costing a total of $4 billion, will replace satellites reaching the end of their service life and add new capabilities.

Pinpoint accuracy

The new satellites are claimed to give three times the accuracy of the previous version, providing a position to within roughly 1 metre. It will also broadcast its encrypted signal through a directional antenna that can focus on a spot a few hundred kilometres across to aid military operations and resist enemy attempts to jam the signal in the immediate area.

The upgrade isn鈥檛 just about staying ahead of the competition. 鈥淚t鈥檚 both a space race and a cooperative enterprise,鈥� says Dana Goward at the Resilient Navigation and Timing Foundation in the US.

Block III are the first GPS satellites to broadcast a signal known as , an international frequency already in use by the European Galileo and China鈥檚 BeiDou satellite systems. Using this signal creates a super-constellation with more satellites than any of the individual systems.

This should improve satellite navigation for urban users, who often have signals blocked by tall buildings. While in theory you only need the signal from four satellites to pinpoint your location, more is better.

It makes sense to cooperate. In recent years, China has overtaken the US and Europe in navigation satellite launches, and its BeiDou system is scheduled to become fully operational this June.

鈥淚t鈥檚 a prestige project, like going to the moon,鈥� says Goward. 鈥淎s a country, China feels it can and should have its own capability. But it鈥檚 also one of these engineering projects where you get lots of spin-off benefits in terms of education and learning.鈥�

Like GPS, BeiDou broadcasts encrypted military-only signals alongside its openly accessible signals. A report in the South China Morning Post last year , which isn鈥檛 possible with GPS. To do this, China could be using a longer-wavelength signal to penetrate water.

鈥�拢3-5产苍
Estimated cost for the UK to build a post-Brexit satellite navigation system鈥�

It is also a major consumer tool. The Chinese government encourages manufacturers to incorporate BeiDou, rather than GPS, into all Chinese-made equipment. Some 5 million vehicles have BeiDou navigation, and 70 per cent of new phones in China are fitted with BeiDou. bikes in Beijing have BeiDou 鈥渢o compel users to park bicycles in designated areas鈥�, according to Chinese newspaper Global Times.

There are concerns that BeiDou equipment might present a security risk to other countries. A聽, a US government body, raises the possibility of BeiDou satellites transmitting malware, although it goes on to say it isn鈥檛 clear how this would happen. 鈥淐ritical infrastructure in a non-Chinese territory would not want to rely on Chinese technology, as the debate about Huawei shows,鈥� says Charles Curry at UK navigation consultancy Chronos.

The desire for a system free from potential outside influences also explains the European Union鈥檚 decision to build the Galileo constellation, which will become fully operational in 2020. It is the only navigation system under civilian control, but has a .

鈥淭his signal is harder to jam and, because it鈥檚 encrypted, much more difficult to spoof,鈥� says Pottle. 鈥淚t gives a more assured positioning capability for government agencies and emergency services.鈥�

鈥淩eliable position is a strategically important resource, the same as energy or medicine鈥�

With the UK having now left the EU, the country no longer has access to this encrypted signal, despite having contributed 拢1.2 billion to the development of Galileo. Curry says this makes sense from an EU national security perspective, but the decision angered the UK government. In May 2018, it announced plans to . A million feasibility study has been carried out, while one estimate suggests that a system would cost .

鈥淎ssessing what a UK system could look like, and how it would meet the country鈥檚 needs, is the purpose of the current phase of work. The potential specifications, cost and schedule will depend on the outcome of this work,鈥� says a UK Space Agency spokesperson.

Curry is in no doubt that the project will go ahead in some form, citing the vastly more expensive HS2 rail project as a sign that the UK government is willing to spend on infrastructure when there are perceived benefits.

Meanwhile, Russia is beefing up its GLONASS system. Like GPS, it was started in the cold war period with military backing, but it was only completed in 2011. GLONASS satellites have a shorter design lifetime than the other systems (between seven and 10 years rather than 15), so despite the large number of launches there tend to be fewer available for use. At least 24 need to be operational to provide global coverage, but Russia currently has only 22 active.

Recently, Russia has shown a new determination to keep GLONASS competitive. In January, ISS-Reshetnev Company, the chief contractor for GLONASS, announced it had received orders for 27 more satellites up to 2025, and that the rate of launches was set to double in the coming year.

鈥淭here are some signs they are upgrading the technology in their new satellites, and planning to join in on L1C,鈥� says Pottle. This would see all four satnav providers forming one super-system for civilian users 鈥� a happy ending for everyone.