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U.S. Deploys Satellite Jamming System
CNN has an article about a ground-based satellite jamming system that "uses electromagnetic radio frequency energy to knock out transmissions on a temporary and reversible basis, without frying components". Is this just another old school EM jamming technique, or something new? Of course they won't say, citing "operational security" concerns.
This is part of the threat the senior US official made at a London conference on Galileo.
The senior official promised that in the event China used the Galileo system against the US, the US would attempt what they called reversible action, but, if necessary, they would use irreversible action, to knock out the Galileo system.
Article on the threat
I use to have a funny sig, but slash cut it off, and I forgot what the punchline was.
"Anti-radiation missile" is a military term for anti-radar missiles like the Shrike and HARM, or for EU types the ALARM. Doesn't have anything to do with nuclear radiation.
The main reason Europe and the rest of the world was a civil controled system as they don't like the thought of the USA switching off or degrading the GPS signal as the civilan airlines require the signal for safe flight.
It may interest the readership to know that Russia also have a similar system as do China. Last I heard, China had been invited to join the program, had accepted, and were going to contribute their sats related equipment to the program. An invitation had been sent to Russia but the last I heard the negotiations were still on going, but a sucessful outcome was likely.
It may interest you to know as well the Russia is the only nation on Earth to have a specific armed forces for space like other nations have an Army, Air Force and Navy. They also did (do?) have the first working anti-sat weapons.
Anyone remember Captain Midnight and the HBO incident?
Tracking dish, knowledge of the frequencies in use, signal generator and amplifier and you're pretty much there.
Of course if they're using DS spread spectrum and they don't have the spreading code, it could be considerably harder, though turning up the power sufficiently would probably desensitise the front end of the satellite enough to stop it from working.
Have you ever gotten those places on your FM dial, where it sounds like 10 different stations are coming in at once? That is intermodulation distortion. Very large signals competing with other very large signals. This is most likely what this "weapon" does. Just overloads the telemetry, data channels, etc of a satellite receiver. It takes alot of current to produce overload resistant receivers, and current is always at a premium on satellites, so I would expect weak receiver front ends that are subject to this ground interference.
Not unless you can manage to fry ONLY components that the sat doesn't need for communication, and there are, oh, say, zero to few of those in comsats.
The difference between spam and poop is that you don't have to dig through septic tanks looking for real food. -- Me
it's called a remote, last i checked..
we can't even handle Iraq and you're worried about world domination?? Holy shit that's funny.
If we were not worried about public opinion, we could just bomb the hell out of the place, turning the cities into craters.
What we have trouble with is personal relations. The US is a big geek: technically powerful, but no people skills.
Table-ized A.I.
The uplink and the downlink are typically at quite different frequencies, say 11 GHz v.s. 14 GHz. so knowing the frequency of the downlink doesn't really help you... yes, I'm work with civilian satellite communications although I'm not an RF expert.
Computer scientists often refer to an order of magnitude when going from problem sizes of N squared to N cubed, which is again tied to an additional power in the "radix" of the problem at hand. Computer scientists also use the colloquialism, in base 10, so it really isn't a binding definition.
Computer scientists who deal in computability and algorithm analysis (like me) use crazy-ass non-math where numbers are pointless and an order of magnitude only really occurs when you go from linear to quadratic, from quadratic to cubic, and from cubic to exponential. The difference between N^4 and N^100 is basically meaningless when you're dealing with Big Oh or other algorithm analysis notation.
In summary, who the hell knows? It's one of those cliche quasi-mathematical things people say to indicate something is "super big" compared to something else. It's like English majors saying, "If you have X cars, you need Y tires," without realizing that they have told me nothing about how many tires I need, have apparently defined Y as an implicitly dependent variable which is ambiguously related to X. I don't know how many tires that works out to be, but it's at least an order of magnitude more than my unicycle.
It doesn't matter what base you're in, an "order of magnitude" always means '10' times. If you're working in base 16, for example, it means 0x10.