Galileo : US - EC negotiations outputs.

In article ,
Sander Vesik wrote:
Hmm.. I wonder if one could use ground based masers to knock out navsats -
after all you do know which frequencies to target for best effect.

Not easily, I think. Remember, they're all transmitter -- they don't
*receive* at those frequencies, so there's no reason why they would be
particularly vulnerable there.

(Also, you would not use a maser for this. Masers are not like lasers;
they specialize in being ultra-low-noise amplifiers for extreme-high-end
receiver systems.)

(Generating coherent radiation is easy at microwave frequencies -- most
microwave transmitters are coherent -- but generating a really tight beam
is inherently hard regardless of the exact type of transmitter. Microwave
wavelengths are 4-5 orders of magnitude longer than that of light, and the
beam's inherent tendency to spread due to diffraction is larger by the
same factor... so you need *optics* that are larger by the same factor to
generate an equally tight beam.)
--
MOST launched 30 June; science observations running | Henry Spencer
since Oct; first surprises seen; papers pending. |

(John Schilling) wrote in message ...
(Henry Spencer) writes:

In article ,
John Schilling wrote:
run by a large consortium that will be slow to make such decisions except
in an obvious dire emergency. This is, on the whole, a good thing.

If anyone, anywhere, builds a batch of Galileo-guided cruise missiles which
end up killing American soldiers while a large consortium of Europeans are
still arguing about whether to pull the plug, the consequences would be
almost unimaginably bad.

The situation is unlikely to occur unless it's deliberately contrived. If
there is enough warning of trouble for consortium action to be seriously
discussed, then there should be enough warning to deploy jammers.

Global shutdowns or accuracy/precision degradations are simply a poor way
to deal with such threats. Military forces, American in particular, are
going to have to get used to the idea that if they want to mess up
navigation for the bad guys, they have to do it with jamming. There are
increasingly too many good guys depending on accurate, precise navigation
for it to be reasonable to mess things up for everyone worldwide in hopes
that it will inconvenience the bad guys.


But that puts it squarely in the technical arena. To what extent does
Galileo use spread-spectrum techniques that make it resistant to jamming?
To what extent can Galileo's operators selectively deny precise targeting
data in one theater without shutting down the whole system globally?

These questions have to be settled before the hardware is built, and if
they are settled in a way that leads to U.S. soldiers dying when different
technical decisions could have allowed a different outcome, the questions
asked then about the technical decisions made now, will be ugly ones.
I think you are missing the whole point. The benefits of reliable,
accurate and widespread navigation system are huge even at this
moment, and would be even higher as it will become used in more and
more applications. The drawbacks (precision targeting by roque
elements) are not as tragical as you make it sound. Yes, they would
complicate the life for the military, but they will find their ways
around (jamming, shooting down the missile, whatever).

When you think about, anything in the hands of bad boys complicates
the life of a military. For example, the military would love to have
monopoly on all vehicles, to deny any mobility/car bombs/whatever to
its opponents. Now, that would have been a cake walk! But the benefits
of having a car are simply too big compared to the risks of having bad
guys use them against you. And historically, there was never a chance
to stop the bad boys getting cars.

I think you and US perhaps though for a while that it is indeed
possible to stop the bad guys from having an easy access to
positioning systems. US is now starting to accept the futility of such
efforts. You will as well, eventually.

As for the terroristic Galileo guided cruise missile attacks or
whatever is your fear. Those can be done now, using GPS. Would you
blame US?!

Stefan

"Sander Vesik" responds in
stupor to say

Could you please try to not be a complete idiot when
posting about international issues? If non-consensual
shutdown of Galileo would in any case or way be an option,
US would have spent far less time and effort on the issue.
An attack on Galileo over such would be equivalent to use
a biological weapon designed to kill cows in France over a
meat imports related trade dispute.

Hmm.. I recommend you check into the issues and discussions
that just took place on Galileo. By "non-consensual
shutdown of Galileo" I assume you mean the ability to
selectively jam Galileo signals in a region of the globe by
the US (or EU) militaries, without per se taking down the
GPS M-code signals.

From GPS World Magazine, Feb 2004, discussing the recent EC
and DoD coordination meetings.
"A series of classified meetings allowed technical
experts on both sides to compare test results and analyses
of the effect of various Galileo frequency options and
signal structures on the M-Code and the US DoD?s ability to
to jam open signals regionally. That ultimately led to
the dropping of the proposed Galileo BOC 2,2 for the OS and
PRS signals. The discussion now revolves around the
comparative effects of the BOC 1.5, 1.5 and BOC 1, 1 on the
M-Code with the US arguing for the narrower bandwidth."

The agreed to change in the Galileo signal allows the US to
selectively jam the Galileo signal in regions of the world,
without significant impact on the US M-code, used by
military grade receivers. The Europeans decided to move away
from their BOC 2,2 signal to something that would allow the
US to selectively jam the Galileo signal in regions of the
world without significantly impacting the GPS M-Code
signal. This was a significant change from the original
European position.

Non-consensual shutdown of Galileo in regions of the world
while keeping the GPS M-code up appears to not only be an
option, but recognized as a potential need.

I believe your other comments are even further
off base and not worthy of further discussion.

(Henry Spencer) wrote:

And as others have noted, one-watt noise jammers will not be large or
costly, and could easily be sprinkled around generously.

Only so long as you don't have to account for the power source.

D.
--
Touch-twice life. Eat. Drink. Laugh.

Sander Vesik wrote in message ...
It is not "just" a question of control - control is merely one part of it,
and GPS would need a lot of redesign to meet those. Which is unlikely
to happen, and similarily, a system that would use GPS for navigation and
use add-on satellites for the rest is unlikely as it would broadly cost
the same as Galileo and still have all the drawbacks of GPS.

GPS is already getting a redesign to improve accuracy and provide
signal integrity, and the different levels of service and interational
cooperation parts of Galileo are irrelevant to the USAF model of "we
control it, and let other people use it at our pleasure, which is
ideally frequently enough that they get totally addicted to it and if
we need to we can give them the shaft."

Galileo is not really a EU navigation system, its a EU + ESA + Russia +
China + India navigation system.

In techonological, economic, and military terms, there's not a lot of
difference between the EU and EU + Russia + China + India.

-jake

John Schilling wrote:

Unmanned satellites, aren't something people get excited about. If

Doesn't apply to ones that are used for traffick control or the functionality
in your 3G phone. 'Galileo is gone' is very unlikely to not affect the daily
lives of a large amount of people.

Galileo suddenly goes silent, the USAF isn't talking, and ground-based
telescopes aren't showing debris clouds at Galileo's orbital elements,

satellites are very unlikely to simply stop responding for no particular -
or detetcable - reason at all, even less so for a constellation of 30
satellites. USAF has no particular monopoly on satellite related technology.

you're left with a couple of boring old talking heads spouting technical
jargon trying to compete for airtime with coverage of the hypothetical
war here on Earth that started the whole mess.

--
Sander

+++ Out of cheese error +++

Larrison wrote:
"Sander Vesik" responds in
stupor to say

Could you please try to not be a complete idiot when
posting about international issues? If non-consensual
shutdown of Galileo would in any case or way be an option,
US would have spent far less time and effort on the issue.
An attack on Galileo over such would be equivalent to use
a biological weapon designed to kill cows in France over a
meat imports related trade dispute.

Hmm.. I recommend you check into the issues and discussions
that just took place on Galileo. By "non-consensual
shutdown of Galileo" I assume you mean the ability to
selectively jam Galileo signals in a region of the globe by

The poster I was replying to clearly meant something different from
jamming it in a locale. Jamming != shutdown.

--
Sander

+++ Out of cheese error +++

Ian Stirling wrote:

Derek Lyons wrote:
(Henry Spencer) wrote:

And as others have noted, one-watt noise jammers will not be large or
costly, and could easily be sprinkled around generously.

Only so long as you don't have to account for the power source.

Because 4W solar panels and 12V 2Ah lead-acid cells cost at least
several billion dollars each.

Certainly not several billion dollars each, but not cheap enough to
scatter one every kilometer or so.

D.
--
Touch-twice life. Eat. Drink. Laugh.

Derek Lyons wrote:

Ian Stirling wrote:


Derek Lyons wrote:

(Henry Spencer) wrote:


And as others have noted, one-watt noise jammers will not be large or
costly, and could easily be sprinkled around generously.

Only so long as you don't have to account for the power source.

Because 4W solar panels and 12V 2Ah lead-acid cells cost at least
several billion dollars each.


Certainly not several billion dollars each, but not cheap enough to
scatter one every kilometer or so.

D.


The range discussed is 22km, if I am following the thread.


That means one or two could easily cover Baghdad. I seem to
recall the US complaining last year that the Russians had exactly
that sort of jamming system in place at the Russian embassy during the
war.

http://www.command-post.org/archives/004635.html
http://in.news.yahoo.com/030324/137/22l8n.html

Derek Lyons wrote:
Ian Stirling wrote:

Derek Lyons wrote:
(Henry Spencer) wrote:

And as others have noted, one-watt noise jammers will not be large or
costly, and could easily be sprinkled around generously.

Only so long as you don't have to account for the power source.

Because 4W solar panels and 12V 2Ah lead-acid cells cost at least
several billion dollars each.

Certainly not several billion dollars each, but not cheap enough to
scatter one every kilometer or so.

Are you sure? It would add about $15 at most to the price of the unit.


D.

--
Sander

+++ Out of cheese error +++