Interview Space policy expert Dr Bleddyn Bowen, of the University of Leicester, has told The Register that the UK faces considerably more hurdles replacing Galileo than just coughing £92m of "Brexit readiness" readies for a feasibility study on a homegrown version.
The good Doctor's comments are timely, as the British government snuck out a statement at midnight on Friday to the effect that the UK is indeed going to have a crack at building its own version of the navigation system.
Citing concerns about the military having to use a secure system, the development of which it was not fully involved in, the UK's Prime Minister, Theresa May, stomped off in a huff to work out how to use the US's "trusted" GPS instead while Blighty potentially spanks billions on its own effort. Ouch.
Bowen, whom eagle-eyed Reg readers might remember patiently explaining to Parliament's Exiting the European Union Committee how satellite navigation worked back in May, has pointed out that recent UK grandstanding on building its own version simply won't, er, fly.
There are oh-so-many issues, starting with a lack of spectrum for the things to actually communicate on.
Bowen explained that "hammering out where in the spectrum we can use is extremely important because that's also partly why America and the EU had such a spat in 2003, when the EU was pursuing its Galileo system. Because the way the EU originally wanted to do Galileo would interfere with GPS's operations."
It took a while, but the two countries eventually came to an understanding that made the systems interoperable. Neat.
The International Telecommunications Union (ITU) has also allocated portions of the available spectrum to China's BeiDou satellite navigation system. India and Japan have regional navigation systems in the form of NAVIC and QZSS respectively. And then there is of course the EU's Galileo and the GPS of the US.
There isn't a lot left for Blighty's domestic Global Navigation Satellite System (GNSS) effort. We prefer "Brexit Satellite", or BS for short.
Bowen observed that all GNSSes are not born equal. GPS and Galileo lurk in Medium Earth Orbit (MEO), while China's were, well, all over the place, with some in geosynchronous orbit and others in MEO. "So a lot of the technical stuff can only be hammered out once Britain knows the sort of frequencies it can use."
The UK will need to go to the ITU to scrounge some frequencies for its BS, which, as Bowen said, "is going to take a lot of time and resources".
At this point, those keen to take back control would suggest that Blighty should simply do what it wants as it bestrides the sunlit uplands of a glorious, post-EU future.
Not so fast, said Bowen. "If it just does what it wants, it could generate a system that does interfere with other users and other navigation systems and the UK will face consequences."
While the ITU is somewhat toothless, it does have rules. And the Brits, of course, love a rule. Stomping over the ITU will infuriate the other big players, and undermine the UK's position in the organisation. So "Britain can't be unilateral about this," according to Dr Bowen.
Assuming, after years of negotiation (it took the US and the EU the best part of three years) the UK gets its hands on some frequencies, the problems don't end there. The position of those frequencies in the band will determine the design and position of the satellites. It cannot be a simple copy of Galileo and will "require new innovations", Bowen said. "You can't just copy and paste."
You want to spend £92m on what, exactly?
The UK intends to spend £92m over the next 18 months deciding what to do. Bowen questioned where that figure had come from, pointing out that it is considerably more than the government planned to invest in UK launch facilities such as the Sutherland Space Port.
Bowen called for the government to put its money where its mouth is regarding UK space ports, and said: "If you were really serious about trying to stimulate launch providers for small satellites in the UK, why not effectively triple your original bid and give them £150m? Put that £92m into the launch sector as well, if you're that serious about it."
The US, which provides the GPS on which NATO depends, is in negotiations with the EU on getting access to Galileo's Public Regulated Service (PRS) as a back-up for its own system. It is the loss of access that has got UK military's knickers so very twisted. Bowen sees little point in the UK going it alone and warned against "fatalism" in negotiations. While the UK space industry will, of course, have its snout whipped from the EU trough, Bowen told us: "I'm fairly optimistic that with the right negotiation, in due course, that Britain will be able to get its way back into Galileo's PRS as a passive user."
Finally, as with many space programmes, Bowen reckoned that the already eye-watering price tag (estimated to be anywhere up to £5bn) of Britain's BS would likely not be enough, with the final system likely over budget and behind schedule.
He called for negotiations to continue. "Having British military forces that can work with the same systems as the EU's technological infrastructure as passive users, I think, works for both sides and is not going to really cost the EU much extra because if America could open up GPS in that way to its allies, the EU can open up PRS to its allies in that way as well." ®