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-   -   Post Galileo (https://www.pprune.org/military-aviation/608377-post-galileo.html)

ORAC 2nd May 2018 07:42

Post Galileo
 
The wierd thing is that the UK could launch a LEO GPS system within just a couple of years, based on the rapid advance in cubesat technology and U.K. expertise, along with the massive surge in cheap launch capability. The LEO GPS technology is there - and SpaceX alone intends to launch up to 20,000 cubesats by the middle 2020s. Galileo is becoming operational just as the era of large MEO orbit GPS satellites is becoming obsolete.

https://en.wikipedia.org/wiki/Starli...constellation)

Innovation: Navigation from LEO : GPS World

https://www.thetimes.co.uk/article/u...ileo-8l27sl8fc

UK will launch satellite system to rival EU’s Galileo

Theresa May is to order the development of a British satellite navigation system after losing patience with Brussels over threats to freeze the UK out of the EU’s new Galileo programme after Brexit.

The European Commission wants to limit Britain’s access to Galileo, intended to rival the US-controlled Global Positioning System, even though the UK has been a major backer of its development since 2003. Brussels insists the UK cannot be trusted with sensitive data that provides a secure back-up for the new satellite system even though much of it has been developed in this country. A recent review suggested a failure of satellite systems and the millions of devices such as sat-navs that depend on them could cost the UK economy as much as £1 billion a day.

The dispute has even led to suggestions that the UK could sue for the return of the €1.4 billion so far invested in the €10 billion project. Downing Street stepped up the pressure yesterday, saying that Mrs May had reached the conclusion that the government should start work on a British system.

The UK Space Agency would lead a group to develop options for the new satellite system which would be a commercial rival to both Galileo and GPS, a No 10 source said. It would receive the same level of funding currently being spent on the UK contribution to the EU programme. It would use Britain’s overseas territories and crown dependencies to provide the necessary global terrestrial infrastructure — raising questions about where Galileo equipment, currently slated for the same locations, would be sited.

“The PM is clear our collective security is too important to haggle over,” the Downing Street source said. “We want full access to Galileo, including the crucial secure elements that will help guide British missiles should they be needed to keep us all safe. But if we don’t get access, we will find an alternative.”


BEagle 2nd May 2018 07:45

Brex****, the gift that keeps on giving....

KenV 2nd May 2018 17:46


Originally Posted by ORAC (Post 10135826)
....The UK Space Agency would lead a group to develop options for the new satellite system which would be a commercial rival to both Galileo and GPS, a No 10 source said. It would receive the same level of funding currently being spent on the UK contribution to the EU programme. It would use Britain’s overseas territories and crown dependencies to provide the necessary global terrestrial infrastructure — raising questions about where Galileo equipment, currently slated for the same locations, would be sited.

Since the EU is dependent on using "British overseas territories and crown dependencies" for Galileo, could the UK not hold those locations hostage as bargaining chips to get Brussels to "play nice" with Galileo?

Pontius Navigator 2nd May 2018 19:07

Apart from giving the UK an independent referencing system should the US encrypt their system and lock others out, what does a 4th system bring to the party?

Are all current GPS similar to the original BBC TV - one channel and no ITV? Would new dual, tri, quad band devices be required for the millions of current users?

ORAC 2nd May 2018 19:24

I would imagine they would have to operate in the same band allocated by the ITU. In which case it should simply be a software update, in the same way your mobile phone receives updates to its carrier settings.

BEagle 2nd May 2018 19:25

Your ad hominem comment notwithstanding, Gilbert, it is the useless Davis, Fox, Gove, Johnson and the ridiculous Rees-Mogg who need to 'grow up' and listen to what the Upper House is telling them about this ridiculous plebiscite.

10 straight defeats over their absurd Bills should tell them something, except that they're too arrogant to listen.

wiggy 2nd May 2018 21:05


Since the EU is dependent on using "British overseas territories and crown dependencies" for Galileo, could the UK not hold those locations hostage as bargaining chips to get Brussels to "play nice" with Galileo?

The wording in the Times piece was “ It would use Britain’s overseas territories and crown dependencies to provide.. “ , not that these were the only plots of land on earth that were suitable or that the project falls apart without them .

I suspect If the U.K. drops out the EU will change plans (if they haven’t already) and use other territories (e.g.French ) as required, so no, the U.K. can’t use their own territories as sure fire bargaining chips.

ImageGear 2nd May 2018 21:26


10 straight defeats over their absurd Bills should tell them something, except that they're too arrogant to listen.
Might it be that their Lordships, not to mention members of the lower house, are no longer listening to the spoken will of the people. While the path to Brexit will be strewed with difficult decisions and compromises, it is nevertheless inexorable.
I did not vote for Brexit, however it was the decision of the people which, uninformed or informed, for better or worse, must be respected, else what is democracy.

IG

pr00ne 2nd May 2018 21:48

Er, isn’t the entire British space industry owned by EU companies? Airbus Space, Surrey Satellite etc?

Melchett01 2nd May 2018 22:28


Originally Posted by pr00ne (Post 10136547)
Er, isn’t the entire British space industry owned by EU companies? Airbus Space, Surrey Satellite etc?


Probably - certainly at least a big chunk of it. I think Surrey Satellites actually sits within the Airbus family of companies. At that's part of the problem, as much as we might like to trumpet a UK space capability, I think the cost and infrastructure is simply too much to generate an entirely sovereign capability. We will always be reliant on partners for funding or payload delivery which presents a raft of issues complicating UK ambition. We put a Carbonite 2 based imaging system up into orbit recently for a trial, will be interesting to see how it goes, but knowing what is out there already, I think we've a long way to catch up.

BEagle 3rd May 2018 06:18

Perhaps Mother MayDay should visit the UK's 'National Space Centre'.....??

It's a museum just off the Leicester ring road :rolleyes:

EASA, ESA, Euratom - even Airbus D&S are pan-European organisations in which the UK is a major participant. As for trying to develop a commercial alternative to GPS, Galileo or GLONASS, whichever idiot thought that up needs to look further at the costs! It's taken a long time for EGNOS to get to its current state - and who would bother with some UK-specific BritNav system given the wide range of current GNSS SatNav receivers?

Another daft utterance from an increasingly desperate government...

Heathrow Harry 3rd May 2018 08:13

I think thePM has only asked for a study of feasibility and options TBF

no doubt it'll cost zillions and will be quietly forgotten...

Pontius Navigator 3rd May 2018 08:23


Originally Posted by ORAC (Post 10136417)
I would imagine they would have to operate in the same band allocated by the ITU. In which case it should simply be a software update, in the same way your mobile phone receives updates to its carrier settings.

ORAC, really? Have you ever known British industry to make something to an international standard that wasn't invented here? :O

Aerials 3rd May 2018 15:20

Back to satellite navigation systems, I wish the UK would put up their own system and make it "free to air".

It'll be a lot cheaper than coding everything so that the system operating company can screw different groups of users for ever more. Furthermore, it'll chop the legs off the Galileo operator, making their (and our, it is agreed) investment absolutely worthless.

I'd just like to see a bit of pushback to the 'user pays' philosophy and Government investment benefitting everyone who lives on our group of islands.

Pontius Navigator 3rd May 2018 18:18

Aerials, the only reason HMG would countenance free GPS would be from free competition. Late to the party, we would have no competitive advantage.

ORAC 4th May 2018 06:13

https://www.thetimes.co.uk/article/e...-row-7gc6pczzv

Ex-MI6 head attacks ‘disloyal’ civil servants in satellites row

Britain has been outwitted by the EU over the Galileo satellite system because ministers believed “incompetently ignorant or at worst disloyal” civil servants, according to the former head of MI6. Sir Richard Dearlove wants Theresa May to carry out her threat to leave the £8 billion programme and begin work on a UK-only system before becoming trapped in a Brussels “spider’s web”.

Galileo is a satellite-based navigation system created by the EU which aims to free European nations from having to rely on Russian, Chinese or US GPS systems. It is intended to be accurate within a metre and is considered crucial to UK military and intelligence needs. The European Commission insists that the UK must be blocked from Galileo’s back-up system, needed by the military, as only EU members can have access to sensitive encrypted signal. That has infuriated Mrs May and senior ministers, even those such as Philip Hammond who support keeping the UK closely aligned with the EU. A Downing Street source said the so-called “war cabinet” was united in its determination to force Brussels to back down.

Britain has contributed about 12 per cent of the cost of Galileo, with overseas territories such as the Falklands providing some of the ground stations. The chancellor has now authorised the effective sabotage of Galileo’s development by seeking to disrupt the transfer of encryption technology from a firm in the UK to France.

However, Sir Richard and Professor Gwythian Prins, a former adviser to the chief of the defence staff, believe ministers were naive ever to believe they could force the EU to allow the UK full access to the critical system.

“The idea that the EU might agree to the UK participating on its own terms was always totally unrealistic. British civil servants who sold this idea to their ministers were at best incompetently ignorant or, at worst, disloyal,” they write in a paper to be published on the Briefings for Brexit website. “In the world of EU officials, there can be no deviation from the rulebook . . . So the EU was not ‘playing hardball’ on Galileo . . . It is merely operating within the strictures of its own vast and inflexible acquis of directives and treaties, just as it will do on all aspects of our ‘negotiations’. EU officials will already have assessed the impact of additional running costs, new tenders, recruiting new expertise, restarting work, new ground stations and the legal and technical issues of Galileo without the UK.

“They will have grasped that the UK’s departure means that a considerable chunk of finance, most of the expertise and several ground stations will be lost from the project . . . So they need to trap the UK fly in a spider’s web so that after Brexit we are powerless, but still contributing money and the essential skills the EU needs. Since so much of Galileo is British, the UK might do as the prime minister is reported to be considering seriously, namely develop its own global navigation network. We strongly encourage her to take this prudent step in the interests of our national security.”........






VinRouge 4th May 2018 15:52


Originally Posted by Heathrow Harry (Post 10136826)
I think thePM has only asked for a study of feasibility and options TBF

no doubt it'll cost zillions and will be quietly forgotten...

plus the power output of a cube sat will mean it will be utterly useless in a contested environment.

ORAC 4th May 2018 16:19

VinRouge.

Inverse square rule applies. Read the second link in my original post. LEO cubesat GPS will generate a received power between 300-2400 times that received by the current MEO GPS satellites.....

ion_berkley 5th May 2018 07:39


Originally Posted by ORAC (Post 10138078)
VinRouge.

Inverse square rule applies. Read the second link in my original post. LEO cubesat GPS will generate a received power between 300-2400 times that received by the current MEO GPS satellites.....

Orac,
Just for the record since you keep quoting from this magazine article which is not exactly "neutral" in what it's selling....
Free Space Path Loss = -10 * log10((4*pi*distance/wavelength)^2)
Distance from GPS orbit to 0 degree elevation on Earth (assuming average earth diameter of 12,734,000m) = square root (20200000*(20200000+12734000)) = ~25792766m
Distance form Iridium Orbit to 0 degree elevation on Earth (assuming average earth diameter of 12,734,000m) = square root (781000*(20200000+781000)) = ~3248879m
L1 GPS frequency of 1575MHz

That gives path loss of -184.6dB for GPS and -166.6dB for Iridium, so a difference of ~18dB... or 63x in pprune layman terms.
And that's assuming all other things are equal....a "cubesat" and a Block III GPS satellite are most definitely *not* equal on more points than I'd care to enumerate on pprune.
I'll stop now before this becomes a rant about skewed math to support agenda's...wait, there's a perfect segue back to Brexit....


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