But since when has logic featured in the arguments over Brexit?
FTFY
Rejoice, Brexit Galileo worriers! Your hand-wringing is at an end thanks to research by Brighton-based Professor Chris Chatwin and Dr Lasisi S Lawal of Nigeria's Obasanjo Space Center. Kind of. How we got here Depending on your take on the situation, Blighty was either booted out of, or walked away from, the EU's satellite …
Part of the reason why a sat nav system has so many birds is to retain accuracy in areas with a restricted view of the sky eg cities valleys etc.
As such I am really curious as to what the availability of this system is in the field given that are proposing only 3 satellites to cover the whole globe.
"Brexit means Brexit."
Judging by the downvotes I think we can safely say "Brexit means a complete loss of a sense of humour"
Between our three satellites and a few feet of wall in Cornwall to keep the Mexicans out, we can make a good go of our new found international isolationism.
Although if everything outside the UK becomes a foe, do we even need expensive satellites to hit our enemies any more? Surely just launching things in the direction of the sea should hit something "enemy"...
I've got it! Long sticks. GPS/Galileo/BS receivers on long sticks. Sticks are cheap and they could be telescopic to cope with different sized valleys and buildings. Each tank could have one, and each platoon could have two in case the soldier holding the first one got killed or got tired.
Ooh I can really feel the good old fashioned plucky British innovation spirit returning. Hey we could make the sticks from Meccano!
As such I am really curious as to what the availability of this system is in the field given that are proposing only 3 satellites to cover the whole globe.
Galileo had two core jobs. One was sovereignty/independence from US GPS, the other was better positioning at higher latitudes, where the GPS orbits were not quite so well optimised.
One would have to conclude that a geostationary bird (which by its nature is equatorial) is not going to be able to augment the Public/unencrypted Galileo signal at higher latitudes as effectively as it would in say, Abuja (all of 9deg north). To get better coverage of (say) the Outer Hebrides, you'd have to look at some sort of exotic orbits in the style of India's Regional Nav System, which uses 7birds in very elliptical High Earth Orbits to cover India/Indian Ocean.
But that wouldn't enhance your signal globally (which would likely upset the RN, as well as Army/RAF forces in the Falklands, Diego, etc), just regionally - though I suppose the proposed three Geostat birds in addition to your super-duper Northern-Europe HEO birds would give you pretty good augmentation everywhere that matters.
The better solution of course is to just apply for PRS access the same as Norway. Seems like at least one person in the EU understands that European Defence and EU Defence are not the same, but are inter-dependent.
And that's why EGNOS is a joke. You can't get much signal from geostationary satellites on a mobile receiver in these northern climes unless you're in an open area. I remember when EGNOS first came online and the GPS receivers I worked with (u-blox, pretty damn good ones) started using the augmentation data, the end result of which was to make the fix less accurate rather than more. In the end we had to disable augmentation in the receivers.
we'd have EGNOG
[Shudder]. No thanks. T'missus insists on drinking something called "a snowball" which, to me, looks like someone has put snot in a glass, added yellow food colouring and then topped it up with lemonade.
I'll stick to my cider. And single malts. And gin.
The early GPS plan back in the '70's was for only 3 birds, as I recall. They quickly found out about coverage being restricted by all sorts of things on the ground like cities and terrain. I suspect that the people proposing this might have access to the early plans and other paperwork. Having worked some on this back then, I don't remember what the timeline was for de-classification.
This is so they get an additional signal in addition to the GPS/Galileo signals.
The ideal is that the additional signal is enough to increase the accuracy.
How that is supposed to work without line of sight to the geostationary satellite (as mentioned above) is the question.
With GPS, they knew from the start that four satellites in view would be required, three if the receiver had a good atomic clock. The system preceding Navstar-GPS was Transit; That one, with three satellites, was fine to provide daily position updates to your handy battleship or nuclear sub. The rest could be - and still can be - handled with inertial navigation.
I did get a navigation fix back when only four Galileo sats were usable. I also just managed to build a receiver and get a fix before Loran was crippled. There are a few ways to build a navigation system, but if it isn't really expensive, it's not politically hot, so forget about those solutions.
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Can't but see the analogies here. Create a problem totally of your own volition. 2. Realise there are downsides. 3. Propose a vague solution citing 'alternative technical arrangements' that doesn't actually address the problem at all.
This is hardly innovative or new is it? Even the 'piggy back' idea was used by ESA from the outset. It doesn't offer more independence from other peoples sat-navs so we can't use it to bomb Brussels. And what do we gain? I guess it makes self driving cars slightly easier - but those are now going to drive themselves off the RoRo ferries, without even the pretence that bolting in a seat and attaching number plates meant 'great British auto industry'.
Given that our own' space industry is never going to be able to compete with the grown ups, I wish we would concentrate public money on doing the important and fun things - earth observation satellites to fill the Trumpian holes and planting flags on other planets. We would spend as much money, support as much industry, but actually achieve something positive in return.
A launch capability is only a part of the space industry overall. Just because you don't have a significant presence in one aspect of something, it doesn't mean you have to be an irrelevance in the overall piece.
(by similar logic, would you argue that the USA has had its day so far as manned spaceflight goes? They're largely beholden to the Russians to get people aloft to ISS)
"would you argue that the USA has had its day so far as manned spaceflight goes?"
Yes. Yes, I would.They don't know whether they want to be in orbit, go to the moon, Mars or asteroids and, as a result, will almost certainly manage to do none of those things. I'm not criticising NASA or the engineers and scientists - they are top people - but the anti-science, trumpist-fantasy culture in which they are forced to operate.
Taikonauts are where manned spaceflight is going. They have an aim, motivation and focus.
YMMV.
Yes. Yes, I would.They don't know whether they want to be in orbit, go to the moon, Mars or asteroids and, as a result, will almost certainly manage to do none of those things.
A fair assessment of US Government-funded Spaceflight.
Not perhaps of the private sector which has got sick of waiting on the politicians and is busy doing it themselves (c.f. SpaceX, Blue Origin, Rocket Lab. Actually even ULA's Vulcan will do good stuff, albeit half a generation behind SX/BO).
"Not perhaps of the private sector"
A fair rejoinder and I may be under-estimating their ability, will and funding.
I still think, if I was a betting man, I would wager on the Chinese reaching Mars with a manned vehicle before them but you are quite correct that is not, by some way, the slam-dunk I envisage compared to NASA.
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Dear Mr Grayling
I have been requested by the Nigerian Space Agency to contact you for assistance in resolving the matter of access to GPS. The Nigerian Space has recently acquired a satellite onto which a GPS alternative could be placed. Unfortunately due to international restrictions, we cannot help you until funding has been made available. Please to facilitate this wire £100 million to the attached agency back account, and we will launch your new GPS system for you
Yours Faithfully
Prince Boateng III (Acting head of NSA)
P.S My brother also owns are large number of RORO ferries. I would be please to make these available for another £100 million
>P.S My brother also owns are large number of RORO ferries. I would be please to make these available for another £100 million
That's your problem. Only companies who own zero RORO ferries are eligible for £100 million government contracts
Unfortunately Johnny foreigner tends to object to you installing transmitters around his capital city immediately before you bomb it.
So it becomes necessary to make the vans rather more robust (with armour and tracks and big guns).
Once you have gained sufficient on-the-ground control to install the e-loran system at your target it seems rather churlish to then drop precision guided munitions on it.
I came here to say pretty much the same thing. Fair Albion (& ancillary islands) is small enough that it would probably cost less in total than a single satellite launch!
As for military targeting, just use the US system for that. All y'all have been our lackys in that regard for decades anyway, so no real change ... and more savings! A couple billion quid here, a couple billion there, and pretty soon you're saving REAL money!
"it does attempt to address concerns that the loss of access to the PRS could lead to lower accuracy"
I'm sure I've said this before, but no such concerns exist. The Commercial Navigation signal provides exactly the same accuracy as the Public Regulated Service signal. The only difference between the two is that the Commerical signal could in theory be switched off. Despite this nonsense being constantly brought up by Brexiters to try to portray the EU as totally unreasonable and cutting us off from vital security services, the fact is that even if we're unwilling to negotiate a sensible deal, we can simply pay for normal commercial access. As long as the French don't decide to invade, the difference between Commerical and PRS is non-existent.
It's also worth noting that accuracy is a fairly pointless thing to be worrying about in the first place. The normal, unencrypted signals for both Galileo and GPS give accuracy of about 1m. There are very few applications where improving that down to 1cm makes any meaningful difference. In particular, things like steering warships and targetting missiles absolutely do not depend on cm level accuracy. Even if we were cut off from everything and stuck using the open access signal, there would be precisely zero impact anything related to military or national security. Those might be great buzzwords to shout about to get people riled up, but they have nothing whatsoever to do with the Galileo Brexit shenanigans.
There’s a much cheaper option.
The navigation signal doesn’t need to be located on the geo satellite. There are loads of telecom satellites already up there physically capable of digital flexible routing to transmit a signal at L-band nav frequencies if allowed by regulators. Inmarsat can, for example, among others.
The signal can be transmitted from the ground station up, and routed downwards into the global (or regional) beam. The complication is only that the satellite wanders about, which needs to be compensated in the signal. That’s hardly rocket science :)
Cost is maybe ten million to develop the ground signal generator, and a few million a year to rent the transponder from satellite network operator.
Why is everyone using large constellations of LEO satellites to provide positioning? The problem with geosynchronous is that it isn't a stable orbit since the Earth isn't perfectly round, so the satellites move in a little figure 8 pattern (analemma) and occasionally need little corrections due to "space weather". The orbits of LEO satellites aren't perfectly stable either (changes in the Van Allen belts can induce a bit of extra drag that needs to be compensated for) but aside from that their orbit is easy to calculate and predict than geo. And they are MUCH closer, meaning the receiver's clock can be less accurate and still get good results.
Maybe the chip scale atomic clocks would overcome these concerns and allow geo satellites to perform this role. If so it would be easier to piggyback this functionality onto a geo satellite that is soon to launch - or better yet just require everyone who launches one under the UK flag to include the functionality, so you have plenty of redundancy making it more difficult for an enemy to knock you out.
The GSO satelites don't provide navigation in themselves. the problem with GSO, apart from it being a jolly long way away and so needing rather beefy signals, is that the satelites are all in a line so the position solution is rather crap.
This proposal, like WAIS and EGNOS, simply rebroadcast extra information (time and correction) sent from the ground, to all the users of the regular system to improve their position. Not to mention confidence in the position, the original driver for WAIS was the FAA wanting to replace ground beacons but wanting aircraft to have some way of detecting GSP errors
You can do a much better job sending corrections from the ground with more locality, but the advantage of GSO is that a single satelite broadcast can cover a big chunk of the continent.