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How to Jam a Worldwide Satellite TV Broadcast 326

An anonymous reader submits: "According to an MSNBC article, 'it's simply a matter of aiming a strong signal at the uplink transponder on the satellite and overwhelming the...broadcaster's signals...You need a dish, some power, not too much. You put up a test pattern ... and do a sweep and find the transponder on the satellite you want to jam. It could even be smaller than the standard 6-meter dish. It could be a small dish with a lot of power.' This was apparently how an Iranian satellite television station was knocked off of Loral Skynet's TelStar-12 a few days ago. Loral contacted TLS, a company which specializes in satellite broadcast security, who quickly located the source of the jamming to Cuba."
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How to Jam a Worldwide Satellite TV Broadcast

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  • by Anonymous Coward on Saturday July 12, 2003 @11:27AM (#6423720)
    How original. I hope someone doesn't try that on the internet.
    • In addition to the U.S. military base and Camp X-Ray at Guantanamo Bay in Cuba, I seem to recall that there is an NSA/CIA/DIA electronic signals intercept and listening station at Guantanamo [].

      From the book ''The U.S. Intelligence Community''
      At Guantanamo Bay, Cuba are more than 100 members of the Guantanamo Naval Security Group Activity []. Employing an AN/FRD-10 antenna system, the unit intercepts Cuban and Soviet military communications in and around Cuba and the Caribbean Basin.

      It seems more likely th

      • by Phil-14 ( 1277 ) on Saturday July 12, 2003 @02:28PM (#6424473)

        You know, it occured to me that the TV stations in question are broadcast from the United States, and that this jamming has happened at the exact same time that there has been major unrest in Iran by people revolting against the theocracy there. The US does not approve of the Iranian theocracy; remember the "axis of evil" speech? That the jamming happened when it did seems to indicate that it was intentional, and was to the benefit of our enemies. That you therefore conclude that it was done by the US says a lot more about you than it does the US.

        I would instead direct your attention here, [] and here. [] If Iran and Cuba have been working together, this suggests that the Cuban government really was the source of the jamming. If you feel sympathies towards the Cuban government such that you're unwilling to believe that they'd support the Mullahs, I suggest you reconsider them.

        • by securitas ( 411694 ) on Saturday July 12, 2003 @04:32PM (#6424919) Homepage Journal

          The fact that you decided to resort to a personal attack and innuendoes says far more about you than anything else you had to say. Instead of behaving like a reactionary, McCarthyist zealot and making claims about all sorts of conclusions that I supposedly reached, try reading a little closer.

          I said it seems more likely that a signal would have come from Guantanamo. Considering the massive signals operation there, that's perfectly reasonable.

          Someone else mentioned in the thread that it's possible that it was an accidental jam if it was the USA because mistakes like that have been known to happen. A more cynical view would be that it was intentionally done to manufacture an incident like the Gulf of Tonkin hoax that was eventually used to justify the Johnson administration's massive expansion of the war in Vietnam. The final possibility that is mentioned in the article is the Russian-built Cuban station. It seems strange that the Russians would have two stations that were only seven miles apart (before the closure of Lourdes), but that is also entirely possible.

          The fact is that neither you nor I have any concrete proof of who was responsible for the jamming. Everything else is speculation.

          The CNN Los Angeles bureau reported in June that the backers of the U.S.-based Iranian dissident satellite television stations are Shah-ists, showing the portraits of the Shah plastered all over the studios. We now know that a 1953 coup orchestrated by the CIA, helped overthrow the short-lived, democratically elected Mossadegh government and snuffed out budding democracy in Iran. The U.S. then installed the Shah and trained his notoriously brutal SAVAK internal security forces. The Shah went on to become one of the most savage dictators of the 20th century until the Iranian revolution in 1979.

          To get back in bed with the Shah's supporters today is directly counter to the stated goal of fostering a democratic, free society in Iran which might have thrived if not for the U.S.-backed coup 50 years ago.

          To Phil-14: The last time I checked I have the right to free speech. It seems you would prefer that we live in a Stalinist, Communist regime that would put an end to anyone who didn't agree with your narrow point of view.

          The MSNBC report may be 100% correct. An open mind will at least acknowledge that there are other possibilities.

          • hahahaha (Score:4, Insightful)

            by Phil-14 ( 1277 ) on Sunday July 13, 2003 @02:09PM (#6428939)

            Hmm. You accuse me of wanting to restrict your speech. This is an ad-hominem attack; at no point did I say you should be arrested and jailed for what you believe. The bit about the TV stations being supporters of the Shah... it's unproven, and it sounds like you're trying to change the subject. First it was, "only the evil Americans would jam the TV station," and now it's "you know, we really shouldn't be cooperating with that TV station."

            CNN are the people who admitted to censoring various news broadcasts out of Iraq in the days when Saddam was still in charge there, so he wouldn't kick them out. I wouldn't be suprised if they'd do the same for other middle eastern dictators they needed to "keep access to."

            I don't know if you've been following the news, but also, this week, student protests against the regime, by people who want democracy, and not the Shah back in power, were brutally suppressed by the government and what the press has been calling "pro-government vigilantes," which are not vigilantes but in reality Syrians and other Arabs hired by the government as enforcers, because they don't even trust their own people in the security apparatus anymore.

            Given that set of events, the same week, and the fact that the signals came from Havana, I think we can rule Guantanamo out for now.

            I wouldn't be suprised if future jamming came from the Cuban side of the border between Cuba proper and Guantanamo; it would be a nice way of utilizing all the useful idiots in the west.

            It's suprising that everyone's so suprised to find that the Cuban and Iranian governments have been cooperating already for years. What's one more instance of cooperation in this case?

            I would suggest that in your rush to blame everything on the United States, and not even believe that one dictatorial regime (Cuba) would support another (Iran) you actually share characteristics with some of the anticommunists of the 50's, who in their rush to combat communism wound up in bed with people like the Shah, or Ferdinand Marcos.

            I mean, look at your use of the term "McCarthyite." It's functional use is for any conservative that argues back against a progressive. It's a stick the liberals have been using against the conservatives for the past forty years. By pontificating on behalf of the Cuban and Iranian regimes (and the "it must have been the US doing the jamming" counts as that, I think) you run the risk of making all the same mistakes, and winding up with the same fate: forty years from now the word "Progressive" may be similarly devoid of meaning, except as a stick to beat people with.

      • by robl ( 53384 ) on Saturday July 12, 2003 @02:44PM (#6424543)
        "It seems more likely that jamming an Iranian satellite signal would come from the American dishes at the Guantanamo installation than from Cubans."

        Armchair punditry at it's worst.

        If you'd do some research about NITV [] The TV station is actually broadcasted from the US into Iran. That's right. National Iranian TV (NITV) is produced in the US. And no, I am not making this up.

        NITV, not being state run, has government enemies in Iran for doing things like making fun of the leaders there. So the Mullahs in Iran call the Castro gang in Cuba and get them to do a favor for them.

        This is something the US military would not want to block.
      • It seems more likely that jamming an Iranian satellite signal would come from the American dishes at the Guantanamo installation than from Cubans.

        That's like saying that OK city bombing was done by the US military rather then Tim McVeigh because the military has better access to bombs. According to the article, jamming a sat isn't that hard. I'm sure someone in cuba is smart enough to do it, and if not, I'm certan that there are people in iran who could, and it would not be hard to ship those people t
      • by f97tosc ( 578893 ) on Saturday July 12, 2003 @03:19PM (#6424671)
        From the article:

        three sources associated with the broadcast services confirmed that Loral Skynet, the operator of the Telstar-12 satellite used by the broadcasters, had determined the jamming was probably emanating from "the vicinity of Havana, Cuba."

        One of the sources said that Loral, working with transmitter location expert TLS Inc. of Chantilly, Va., had further fixed the location as "20 miles outside of Havana." Cuba's main electronic eavesdropping base, at Bejucal, is about 20 miles outside of the Cuban capital. The base, built for Cuba by the Russians in the early 1990's, monitors and intercepts satellite communications.

        5, Interesting, eh? More like 0, Stupid. The broadcasts are done by regime-critical expatriots in the US. Why would the US jam anti-iraninan broadcasts based on its own soil?

    • What if they only DOSed the satellite during the commercials?

      Replace obnoxious commercials with something less irritating, such as Cowboy Neal running around naked.
  • by Rorschach1 ( 174480 ) on Saturday July 12, 2003 @11:28AM (#6423722) Homepage
    See the story of Captain Midnight and HBO.. m

    • by K8Fan ( 37875 ) on Saturday July 12, 2003 @11:43AM (#6423796) Journal

      I was watching at the time it happened. HBO likes to spin that the signal was never clear, and that the handled the interference quickly. My experience was that the signal he sent was every bit as clear as HBO's own signal. It's funny that it happened during "The Falcon & The Snowman", a film about a couple of Americans who become spys for the Soviets - and screw up royally.

  • Cuba, eh? (Score:5, Funny)

    by DoorFrame ( 22108 ) on Saturday July 12, 2003 @11:28AM (#6423724) Homepage
    I know how to solve this problem... SANCTIONS! That'll show 'em.
    • You don't think that it came from Gitmo?
      • Of course it did.
        • Why would a pro-democracy channel be blocked by US forces in Gitmo?

          Pretty old news that the Iranian satellite channel originating in California is an anti-Mullah/new-Revolutionary channel.
          • Re:Cuba, eh? (Score:2, Insightful)

            by Malcontent ( 40834 )
            I don't think any of the jammers knew iranian. The US military makes mistaked like this all the time. Raiding the wrong house, dropping bombs on the wrong town, firing on journalist (well they probably meant to that one).

    • The hawks in congress must be pretty confused ... Cubans vs. Iranians - whom are we going to send the military aid?
      • Re:Cuba, eh? (Score:2, Insightful)

        by SN74S181 ( 581549 )
        The Iranian government must have sent the money to the Cubans, considering that the people in charge in Iran are the ones who generally seek to block access to outside news sources to their citizenry.

        So I wouldn't call it 'Cubans vs. Iranians.' Just another example of Cuba exporting repression.
      • Re:Cuba, eh? (Score:2, Informative)

        by mcheu ( 646116 )
        Cuba obviously.

        Even though they've made it illegal for Americans to import them, the Americans have a major hardon for Cuban cigars. Must be all that Cuban siliva. If you smoke those things, and don't know how they're made, you really MUST have a look at a video on traditional Cuban cigar manufacturing. Might help with that whole stop-smoking thing.

        Think sweatshops full of old ladies rolling tobacco leaves, frequently licking their hands and the tobacco leaves to help the leaves stay together.
    • by El Camino SS ( 264212 ) on Saturday July 12, 2003 @12:56PM (#6424108)

      Sanctions, yes. Arms? Hell no.

      Remember what happened the last time that we gave people in that regions unlimited resources and guns? Let's just go out of our way to make sure that we don't do that again.

      Any winner in an armed conflict is rarely going to institute anything but Marshall Law, especially in that region. Meet the new boss, same as the old boss (but with new politics), meaning they have to eliminate all of the old political opponents to make the system work... as quietly as possible.

      Giving the opposing side rifles would sound a little like this to me:

      Good luck Tehran. Democracy didn't come overnight here, we can't send you guns and expect that you will have anything in charge of you other than a gun-toting government from that.

      They have to do it themselves. We have to sit by and watch, there is nothing we should do other than that. The intense hatred of anything US backed would simply do what it has always done in that region... make the people we back look like flunkies for the infidels.

      Anyway, much love to the Iranian people. We're rooting for you and your own future. Decided by you.
      • by zenyu ( 248067 ) on Saturday July 12, 2003 @02:43PM (#6424540)
        They have to do it themselves. We have to sit by and watch, there is nothing we should do other than that. The intense hatred of anything US backed would simply do what it has always done in that region... make the people we back look like flunkies for the infidels.

        There is plenty reason to be hopeful too. There are only four democracies in the region Turkey, Lebanon, Israel and Israel. They are all flawed, Turkey has a huge military industrial complex corrupting their politics and think of they Kurdish minority as subhuman. Lebanon is democrartic but most parts of the country are still occupied by Syria, a monarchy -- purportedly to protect them from another invasion by Israel which no one really thinks will attack again. Israel which refuse to give most of their Palestinian population the vote. And, Iran which has popular elections, but gives religious leaders a veto. Plus the religious leaders run most charities and schools, and have their own militia.

        They all have some hope, the Turkish parliament recently rejected the military's approval of US transit rights. They needed 90% approval of their action from the populace, but it should build their backbone. Unfortunately I don't see the Kurdish situation improving. They really need to be given their own country, I've known Turks that were perfectly reasonable and intelligent human beings that seemed possessed with evil when the topic of Kurds came up. I don't think the desire to join the EU will overcome this hatred.

        Lebanon's benefactor Syria got a moderate dictator by peaceful succession a few years ago that will probably leave Lebanon as soon as they get a peace treaty with Israel. Even without a peace treaty this may happen as the main opposition party in Lebanon wants to disinvite Syria and the current dictator there would likely accept that, if only grudginly.

        Both sides in Israel's civil war want peace and accept each others terms pretty much except for some details like compensation for siezed property and water allocation. There are plenty of foreign donors willing to pay for all but symbolic portions of the bill. What really holds them back is that 70-90% on each side completely distrusts the other side. They have perfectly valid reasons seen close to the ground, but from any other vantage point these two semitic tribes have more common interests than anyone else in the middle east, and as soon as the old warriors like Sharon die (from natural causes) the very young population on both sides of the conflict will have every reason to make up.

        Finally, Iran probably has the best hope of all. If you read their constitution you see it's pretty decent, it even guarantees representation for tiny minorities, Zoroastrians and Jews each get a seat each in parliment and three seats go to Christians, the biggest problem is the guardian council which can reject any law with a simple majority. But, half guardian council which interprets the constitutionality of laws, who usually reject laws from the currently liberal parliment, is appointed by the judiciary. They serve 6 year terms instead of the four that the parliment's members serve, and while right now it's packed with very conservative clerics that keep rejecting reformist laws, this will change because the generation that has just started voting was born after the revolution and have only known the excesses of the Iranian government and don't accept it just because it's better than the dictator that ruled thirty years ago. Really, the only thing that could screew things up is if we start mucking with their internal politics and the liberals get associated with the foreign interlopers. All that's needed is few years to rotate out older appointments and everything changes for the better. Even "The Leader" is elected from candidates selected by experts appointed by the guardians, but if the majority grows just a little bigger for reform the leader doesn't need to change because he won't dare do anything to get in the way of reform for fear of complete overthrow, sorta lik
  • Noooo! (Score:3, Funny)

    by deman1985 ( 684265 ) <dedwards&kappastone,com> on Saturday July 12, 2003 @11:29AM (#6423727) Homepage
    This information can't leak out! We'll be subjected to Mystery Science Theatre 24/7! God save us all!
    • Re:Noooo! (Score:5, Informative)

      by ashridah ( 72567 ) on Saturday July 12, 2003 @12:52PM (#6424077)
      This isn't likely to happen, specifically.

      Your average satellite receiver is setup to deliberately receive and amplify a particular signal, to make it usable by a decoder.

      The satellite LNB (the device at the focal point of a satellite dish) is tuned when installed, and is specifically set to give the decoder a signal of a particular strength. This is usually measured in the order of a particular number of decibells (dB).

      Most receivers will actually shut down if you overload them with signal however. It's possible for you to encounter problems when you tune an LNB, and someone goes and jacks up the output level on the satellite for some reason (like, say, they need to use it to broadcast military signals :) ), unless you take precautions. tune it too low, however, and you encounter signal loss in bad weather.

      This means, that on the satellite that's receiving the uplink, you'll find that if you overload it, it'll just shut down the receiver instead of overriding the signal.

      Don't let anyone fool you into thinking you can drive everyone nuts by replacing their favorite shows with reruns of the original odd couple :). You'd have to actually take control of the satellite (probably not as hard as it sounds, even with modern satellites, really) to get your own signal, and then you'd do it by making it receive a different frequency and you start broadcasting.

  • "And may God help you if that thing carried the Spice Channel."

    -Moe Syzlak
  • by Anonymous Coward
    Taco... fire michael, promote timothy, and then take a sabbatical and let someone else run the show for a while, until you get some passion for the job and stop hating the readers so much.

    Thank you.


    Hank Kingsley
  • Dangerous (Score:5, Funny)

    by Flamed to a Crisp ( 688872 ) on Saturday July 12, 2003 @11:31AM (#6423739)

    This could get very very dangerous. Imagine if some terrorists got ahold of a dish (not very hard these days) and knocked out some vital communication systems. Chaos! Our only hope is that since the instructions have been Slashdotted, the terrorists can't get through.

    • So we should make a dupe of this story.

      That's not enough... we need to flood the story submission database with this story :).
    • This could get very very dangerous. Imagine if some terrorists got ahold of a dish (not very hard these days) and knocked out some vital communication systems

      You mean like CNN?
  • by PS-SCUD ( 601089 ) <peternormanscott@yahoo . c om> on Saturday July 12, 2003 @11:32AM (#6423741) Journal
    How do you make this illegal? If they can beam their signal onto your house, why can't you beam yours at them?
  • by Anonymous Coward on Saturday July 12, 2003 @11:32AM (#6423743)
    Funny, the other divisions of MS seem to think it's some kind of horrible, immoral, illegal thing when you describe how to hack hardware. What happened to "very committed to respect for others' intellectual property and we request the same respect applied to our innovations"?
  • by mrpuffypants ( 444598 ) * <mrpuffypants AT gmail DOT com> on Saturday July 12, 2003 @11:35AM (#6423758)
    In other news, DirecTV was knocked off the air permanently for unexplained reasons today.

    Comcast, AOL/TW, and Cox all declined to comment.
  • by da3dAlus ( 20553 ) <> on Saturday July 12, 2003 @11:40AM (#6423782) Homepage Journal
    "Not if we JAM IT!"
    "Ah ha!"
    "Down scope."
    "Down scope!"
    "Radar...about to be...JAMMED!"
  • muhaha! (Score:5, Insightful)

    by wfmcwalter ( 124904 ) on Saturday July 12, 2003 @11:42AM (#6423793) Homepage
    it's simply a matter of aiming a strong signal at the uplink transponder on the satellite

    Worse, send a really powerful signal (read- military radar magnetron hooked up to mondo dish) and you can permanently fry that transponder, and do so with a burst so brief and directed that it's not terribly easy for anyone to figure out whonunnit. It's a great piece of asymetric information warfare - spend a couple of million dollars to knock out a few dozen civilian comsats, each tens or hundreds of millions of dollars worth. Best of all, it's quite possibly not in breach of any international treaty !

    Excuse me, I have to go now, my mechanical pirnahas are hungry...

    • Re:muhaha! (Score:5, Interesting)

      by throwaway18 ( 521472 ) on Saturday July 12, 2003 @01:11PM (#6424161) Journal
      >send a really powerful signal [...] and you can permanently fry that transponder,

      No, you can't permanently damage a satellite this way.

      The path loss to a satellite in geostationary orbit is around 200dB. Estimate 50dB with a massive dish on the ground and 30dB gain on the satellite. Assume you need to get a watt of power into the satellite to physicall damage the front end.

      You need aproximatly 1 TeraWatt into your dish. The voltage part of the electromagnetic wave will exceed the breakdown voltage of air and you will just produce a lot of plasma in the beampath above your dish. (You can exceed the voltage breakdown of air with a really powerfull laser and get sparks in mid air.)
      • ... Point it at your target satellite. Turn on the power. Wouldn't that do it?

        -Joe G.
  • by ( 664381 ) * on Saturday July 12, 2003 @11:47AM (#6423808) Homepage
    such as using the transponders to carry your own signal . Most sat tv satelites are essnetially dumb transponders , which means (essentially) they receive a signal on one end and pump it out the other end . What is cool is that using DSS (direct sequencing spread spectrum) you can transmit your own data and people will think that it is background noise . I beleive correctly some russians were doing this awhile back and it went on for a couple of years before they got caught.
  • by gilesjuk ( 604902 ) <> on Saturday July 12, 2003 @11:47AM (#6423813)
    You need a huge knife and gallons of jam.
  • by Talisman ( 39902 ) on Saturday July 12, 2003 @11:47AM (#6423814) Homepage
    I work as a communications officer aboard a ship. We pulled into Cape Town on day 1 of the World Cricket Championships. One of the games was being broadcast nearby, until our active radar filled the air with distortion.

    The second the gangway hit the deck, two sweaty, panicked cameramen came charging up, asking to speak to me. I was already at the gangway because I needed to meet a technician.

    "You have to turn off your radar! We're broadcasting the World Cricket Chapmionships LIVE AND YOU KILLED OUR SIGNAL!"

    Me: "Oh. Who's playing?"

    Them: "Pakistan and Bangladesh."

    Me: "Pakistan, eh? Yeah, I'll turn it off ASAP."

    And 20 minutes later, I did ;)

    For any of you gusy that were watching that game, sorry.

    Kinda ;)

    • The Italians have a radar system (their equivalent of aegis, I believe) that wipes out marisat communications. I had to tell the captain he'd have to wait til that cruiser got far enough away before he could talk to the office.

      • by Talisman ( 39902 ) on Saturday July 12, 2003 @12:08PM (#6423890) Homepage
        We were sailing off the coast of Spain once and the Spanish Navy was running military exercises nearby. They had a jammer that scrambled GPS signals, in this case by stripping out all the Westward coordinates.

        The navigational system that shows the ship superimposed on a map by using a GPS feed had us squarely in the center of the Sahara :)

        The ex-Soviet republics are _THE_WORST_ for radar interference. I swear they think someone is going to launch an attack on them every minute of the day. NOTHING but an orgy of signal jamming/scrambling when you get near their coasts. C-Band, INMARSAT, GPS...all yolked.

    • No problem. In any given twenty minutes of a cricket game, the chances that anything actually happened are pretty low.
    • Considering that Pakis are a toprated team and the Banglis are pretty much at the bottom of the ratings the ENTIRE GAME could have finished by then You Insensitive Clod (tm).
      Hell we (the Sri Lankans) beat them (their innings and ours) in less than two hours.. and our guys weren't even trying.

    • What do you do if you meet someone from Pakistan on the street? Spit on them?

      You seem like one of those people that would have gleefully herded the Japanese into concentration camps during WWII.
  • Now does that sound like a cool job, or what?

    It's one of those industries I didn't realize there was a niche for.
  • Countermeasures (Score:5, Interesting)

    by td ( 46763 ) on Saturday July 12, 2003 @11:49AM (#6423823) Homepage
    As has been pointed out, people have been jamming satellite uplinks since Capt Midnite & HBO. So why haven't the satellite folks gone to jam-resistant technology? (I know, it's because of the essential laziness of corporate culture -- geez, it was a rhetorical question.) Spread spectrum is essentially unjammable, if done right (i.e. with cryptographically generated spreading sequences or some such cryptogeek mumbojumbo.)
    • Re:Countermeasures (Score:5, Informative)

      by LostCluster ( 625375 ) on Saturday July 12, 2003 @12:11PM (#6423899)
      Spread spectrum is essentially unjammable

      Huh? By definition, spread spectrum bounces all over the given band of frequencies in some predetermined patern. It makes it a bit harder to jam, because you'd have to cover all of the frequencies with the jamming signal, but not impossible if the attacker can just jam the whole frequency range.

      Furthermore, spread spectrum makes things a whole lot harder on the transmitters on the ground. Let's use a simple example, imagine a satellite with channel space for 6 upbound signals coming from 6 different TV networks that are located at 6 different studios. In simple frequency division, they'd each get 1 slot of bandwidth, and so long as nobody retunes their transmitter to somebody else's frequency it all works. But, in spread spectrum, they'd each be all over the band... unless coordination was very tight between the spreading patern, the 6 sources would keep jamming each other by being on the same frequency at the same moment... you'd need a ton of retransmitting and error correction to get around that.
      • Re:Countermeasures (Score:3, Informative)

        by buss_error ( 142273 )
        you'd need a ton of retransmitting and error correction to get around that.

        Not really. A pre-determined psudeo-random frequency hopping system sync'ed with a time signal from, say WWV, GPS, NTP, or a sync signal from the transponder itself would do fine. However, you are solving the wrong problem with this solution. (Police Fire and Ambulance use something called "trunking" that's quite a bit like this.)

        The problem is that a stronger signal at the receiver can't be rejected based on transmission charate

    • Re:Countermeasures (Score:5, Informative)

      by Detritus ( 11846 ) on Saturday July 12, 2003 @12:11PM (#6423904) Homepage
      The problem is that transponders are relatively simple devices. They receive a band of frequencies and retransmit those frequencies on another band. Anything in the uplink passband is duplicated in the downlink passband. The transponder can be jammed simply by putting a very strong unmodulated carrier in the uplink passband. This hogs all of the power available in the downlink section of the transponder, leaving little or no power for the legitimate users.

      A sophisticated antenna system will provide steerable nulls in its radiation pattern. Once the source of the interference is localized, the antenna can be adjusted to place the null over the source of interference.

      • All true, but I believe the point of the parent poster is: the 'evil corporations' are too cheap to replace every transponder on every satellite whenever a vulnerability is exploited.

        Sorry, I just can't agree with his 'too cheap' accusation. I go with the 'it is much to impractical to do all at once and will have to be upgraded over time' theory.
      • Re:Countermeasures (Score:3, Informative)

        by td ( 46763 )
        Right. So the fix is not to do that -- i.e. don't use simple transponders, but populate the satellite with spread spectrum relays that cannot be jammed by a strong unmodulated carrier because they only watch that frequency for a few microseconds at a time, and can use forward error correction to correct for the interference. In fact, no signal of plausible amplitude that is unaware of the spreading sequence (which possibility we circumvent with a little cryptography) can successfully jam the transmission
  • > Iranian satellite television station was knocked off of Loral Skynet's TelStar-12

    And so it begins... Skynet has become self-aware... and picked a country that supposedly has loads of WMD and terrorists. Guess even AI can be fooled :)

  • by heli0 ( 659560 ) on Saturday July 12, 2003 @11:54AM (#6423846)
    How to Jam a Worldwide Satellite TV Broadcast

    "According to an MSNBC article, 'it's simply a matter of aiming a strong signal at the uplink transponder on the satellite and overwhelming the...broadcaster's signals...You need a dish, some power, not too much. You put up a test pattern ... and do a sweep and find the transponder on the satellite you want to jam'."

    So who from Microsoft or General Electric is going to prison for this DMCA violation?
  • C'mon, lets get creative, instead of blocking out boring TV, lets replace it with eppisodes of Mystery Science Theater 3000 or something.

    Think creative!e
  • I bet Bush sees this as justification to now attack Cuba... Cuba is attacking our right to free speech being blasted into Iran. Time for another 'justified' U.S. attack. ;-)
  • by Psychic Burrito ( 611532 ) on Saturday July 12, 2003 @12:15PM (#6423923)
    Can somebody tell me how the source of such a jamming can be found? The satellite's receiver doesn't have a locator from which direction it is receiving something from, doesn't it? So how is it done? Thanks!
    • by Conor ( 2745 ) on Saturday July 12, 2003 @12:34PM (#6423990)
      According to company website they use radio interferometry. To do this they need another (relatively) nearby satellite with a similar transponder, which also sees some interference. Then they measure the arrival time difference between the signals bounced from the two satellites, using this they can then triangulate the position to within a few miles.

      If you pay them lots of money they'll send out helicopter
      (assuming its not in Cuba!) to find the exact antenna causing the problem.
  • This is indicative of the moral bancrupcy of these regimes.

    Their supposed ideologies are the very opposite. This makes it clear to everyone that they are really the same. They rally around the flag of protecting the dictators, and supressing free speech. That is the true essence of their ideologies.

  • by InklingBooks ( 687623 ) on Saturday July 12, 2003 @12:56PM (#6424105)
    I once asked a friend who designed satellite antenna system what it would take to take over a channel and he said it would be fairly easy. The typical uplink is 30 watts into the sort of large dishes you see at TV studios. Because the link is FM (regular TV is reduced carrier SSB), a signal about twice as strong would 'capture' the receiver and the legitimate signal would simply disappear.

    What's really intriguing about this story is the Cuba/Iran link. For years we've been told that religious extremism in the Middle East was a close kin of religious conservatives (Jewish and Christian) in the US. Yet when Iraq's brutal dictator recently began to cloak himself in Islamic rhetoric, it was primarily the political left in the US and Europe, who wanted to see him left in power. Their old love affair with Stalin was turned on to the foul Saddam.

    Now Iran, an Islamic theocracy, is having trouble with dissidents demanding democracy and who comes to its aid but virtually the only remaining Communist dictatorship in the world.

    Very interesting. It seems that some groups simply want to see the great mass of people regimented and are indifferent to the ideology used to justify the regimentation. Religious or secular, Marxist or Facist, it is all the same to them. Mussolini was, after all, a communist before he was a facist and Nazism had people who were called "beefsteak Nazis"--brown on the outside and red inside. Then there is the Hitler-Stalin pact of 1939. Hitler may have intended to break it at the earliest opportunity, but Stalin seems to have been sincerely surprised when Hitler broke it.

  • There are just so many problems with laser communication from orbit.

    Another little known bit about satellites is that they will completely shutdown when a high power signal is detected. I don't know for how long but that would cloak the perpetrator.
  • by MochaMan ( 30021 ) on Saturday July 12, 2003 @01:17PM (#6424176) Homepage
    Bad day for NITV... first their satellite gets jammed, and then we slashdot their site.
  • by WgT2 ( 591074 )

    That Iranian TV station is a station that has been used in lue of cell phones, and other communications within Iran, to organize protests against the current hard line religious government (because the same government shuts them down). These protests are likely to be precursors to the current member of the 'Axis of Evil' (and I don't mean that sarcastically at all) falling in a relatively peaceful means. Read: U.S. troops not having any intervention therein and the Iranian people freeing and regulating the

  • While watching the Tinammen Square Massacare and then discussing it at MacHack [] in 1989, we discussed the fesability of not just taking Chinese television of the air, but actually taking control of it and getting the real message of what was happening out to the world.

    After a few hours of discussion with some extremely bright folks, we came to the conclusion that 1) it could be done, 2) that it could be done easily, and 3) that we really didn't want the Chinese security services and the US Department of State and the FCC all coming after us.

    What is surprising, is that this hasn't yet been done in any large scale way. The reality is that small forces of 2 and 3 people can wreck havoc in our increasingly connected world. I believe that what keeps this in check is the level of concerns that kept us in check. But what happens we you don't have those concerns? When you have nothing to lose? Then you have the cyber-equivalent of the Palestenian sucide bombers.

    • It happens all of the time when more than one company/group/organiztion have access to the same satellite. When one of them are having problems with the uplink (excessive cloud cover, etc), it's common that a tech for that company would go out to the satcom modem and boost the signal a couple of decibels. This would usually drown out another companies siganl who would than boost their own. Eventually you would get to a situation where everyone has boosted their output signal way above what is normal and
  • Wasn't there a story that came up, perhaps here, a while back about a tech at $RANDOM_PODUNK_SATILLITTE_COMPANY, i think in arizona, who found out one night he could overpower Showtime or HBO's satillitte feed? Didn't he then end up with teams of federal agents mobbing him, calling him a threat to national security?
  • by torklugnutz ( 212328 ) on Saturday July 12, 2003 @02:15PM (#6424412) Homepage
    My mom wanted to install a 2 way satellite broadband connection in the motorhome. The DirecWay [] people said it was impossible to have a mobile dish, because if the uplink signal crosses over into someone elses (like a TV channel) bandwidth, DirecWay gets fined $10,000 per minute. The FCC requires the system to be installed by a professional, as a result. Off the subject now, but it can be done in a mobile situation, by using an expensive ($5000) computerized positioning system. Back to what's relevant, if you tried doing something like jamming a network's satellite signal, you'd be putting yourself at a pretty good financial risk.
  • The signal is originating from somewhere in South America or the Carribean. So, even though Cuba is a bastion of evil, it's more likely coming from Al-Qaeda groups known to be operating in the large Iranian communities in and near Brazil.

    Not a minus for Cuba, but it does further demonstrate Iran's hardliner link to terrorism.
  • The Running Man? (Score:3, Interesting)

    by checkyoulater ( 246565 ) on Saturday July 12, 2003 @03:15PM (#6424655) Journal
    Didn't Mick Fleetwook and Dweezil Zappa do this in The Running Man? [] Remember the scene towards the end where Ben Richards discovers the dead bodies of the so-called winners of the Running Man game? It is at that time he is captured by the resistance (for lack of a better term). He then helps them capture the satellite. If I recall all they had was a bunch of machine guns and one clever geek who made that girl remember the uplink code.
  • by Anonymous Coward on Saturday July 12, 2003 @05:19PM (#6425067)
    Hello there, I would like to clear some things up and shed some light on the matter. (excuse the bad English) Firstly, a satellite related history about Iran:

    We have 6 channels. One is news, one is sport and the other four are mixed channels, showing anything from soccer to documentaries to dubbed American films and series (yeah, death to america baby!!) to English films in original language to japanese samurai black and white films to cartoons etc.. you name it. Ofcourse the news biased towards the evils of America and the poor Palestinians getting killed and so on (one interesting thing is that when 5 Palestinians get killed, they are Martyred (and if there are any kids / women in between the killed, they are mentioned loudly, but if a school bus of Jew kids are killed, then "20 zionists were killed" ... anyways). Since the channels mostly show boring old films or even more boring documentaries, most pople have digital satellite receivers and just watch show and Iranian channels.

    Satellite Receivers and Dishes are 'illegal' in Iran and every now and then the media's attention is focused on the matter and so the local police bitches about and raids a few houses, taking away their equipment and fining them... then gives up. This has become the norm. Since Tehran (the capital city) has over 14 million in population, going round every house and taking away their equipments was not a feasable task. I have written (at the end of this post) what they have done NOW to get the channels jammed and it seems to be working... 90 cm dishes are the norm here. They're big enough to do the job and yet small enough to be concealed easily. 60 cm versions are also available but you need a *really* good LNB (such as Nokia) to get a good signal. Now on to the NITV matter:

    The National Iranian TV station (NITV) is a station based in USA and it mostly broadcasts talk shows and documentaries AGAINST the current regime in Iran so they are America's friend and Iranian government's enemy. Currently, there are 6 or 7 Iranian language satellite channels that can be received in Iran. All are transmitted from "TelStar 12" satellite. About two years ago, the only Iranian satellite channels were NITV and another one I can't remember. Both used to be broadcasted from Hotbird satellite. That
    was until their signals were jammed multiple times (after a few months of broadcasting) and at the end they made the decision of moving to TelStar 12. I remember they issued a statement that Hotbird has received jamming signal FROM IRAN that has worked against the Iranian channels and so on... the funny thing is that the Iranian gov. broadcasts 4 or 5 propaganda channels to the very same "hotbird" satellite and they continued to broadcast their programmes even after Hotbird had found about their dirty trick. Don't you think those hotbird guys should have stopped broadcasting their programmes as a result ?

    Since then, everyone has had to either add a new satellite dish or just add another LNB to their dish (which is set to Hotbird to get those music shows) and receive the Iranian channels as well. Recently there was a lot of talk in the "Majles" which is parliament about jamming signals being broadcast locally to stop people receive the
    channels. And there was debate on whether these signals could be cancerous or not. At the end, they started to send jamming signals while the case remained open in the parliament.

    At first, I laughed at the idea because a satellite dish works by concentrating bounced microwaves to a point where the LNB receives them and converts them to electrical signal. But if the government broadcasts signals locally, then the point of concentration would not be at the LNB part and so it shouldn't really matter huh ? Well, I am wrong and they have been successful (up to a certain level) to annoy the hell out of people and in some areas people can't get a signal. The jamming they are using is sweep based. From what I experienced at a friend's house, the sweep signal was on *any* channel
  • by graybeard ( 114823 ) on Saturday July 12, 2003 @06:01PM (#6425206)
    Once upon a time, the announcer would announce, "This is the end of our broadcast day. Please rejoin WWWW at 6AM." Perhaps this announcement followed an inspirational moment from the Reverent Billy Bob Cross, or the Navy Hymn, or the Star-Spangled Banner, complete with fly-over. If one were lucky, one had just seen the Late Movie, or the Late-Late Movie. Now, it Infomercials as far as the eye can see.

"My sense of purpose is gone! I have no idea who I AM!" "Oh, my God... You've.. You've turned him into a DEMOCRAT!" -- Doonesbury