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Wireless Networking Security Hardware

U.S. Government Sometimes Jams Keyless Car Locks? 349

PizzaFace writes "The Washington Post reports that in certain towns (generally near military bases), on certain days (such as the day an aircraft carrier returns to port), keyless car entry systems and remote garage door openers mysteriously fail. While some frustrated motorists blame aliens, the FCC says the jammed frequencies belong to the U.S. military. The good ol' Post even tracks down a government contractor who all-but-confirms the source of the interference."
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U.S. Government Sometimes Jams Keyless Car Locks?

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  • fp (Score:5, Funny)

    by Zorilla ( 791636 ) on Monday July 05, 2004 @03:28PM (#9615108)
    first po#@)(^*ESDHLKS&^$#HLFSDIHF

  • by 2057 ( 600541 ) on Monday July 05, 2004 @03:29PM (#9615111) Homepage Journal
    There is only a select number of frequencies we can access and use, this was bound to happen.
    • by connorbd ( 151811 ) on Monday July 05, 2004 @06:50PM (#9616471) Homepage
      Whoever modded this a troll doesn't know much about how comm frequencies are allocated. The fact is that according to the article, keyless entry systems are secondary users on their allocated frequencies. Ask a ham what that means.

      For an excellent example, hams were in the last couple years authorized to operate on the 60m band. That probably means nothing to most people, but it's a specific band that is used by amateurs in other countries, with its own unique propagation characteristics. However, amateurs, who generally get the run of whatever band they're allowed, are limited to one particular operation mode (upper sideband) on five channels, one of which is shared with the UK making international contact on that band possible. The reason for the limitation: the primary users on that band are military and emergency-related, they use upper sideband on those frequencies, and they need to be able to clear the channel for their own use, so they have to be able to talk to other users. (It's an annoyance to hams, who are used to being able to operate any mode they wish, but c'est la vie.)

      What looks like the case here is that the remote systems are designed to operate under Part 15 rules, which govern general unlicensed transmission. They're the same rules under which a community low power AM station can broadcast, and are subject to the same terms. In this case, it was an unfortunate choice for car manufacturers, because the frequency chosen is apparently used for certain FCC-allocated classified purposes. Oh well.
  • by evil crash ( 739354 ) on Monday July 05, 2004 @03:29PM (#9615119) Journal
    Mine don't work in the parking lot on the military base I work on, but the work fine at home.
    • by Mister Transistor ( 259842 ) on Monday July 05, 2004 @04:01PM (#9615434) Journal
      The interference is in the Military A-Band, which covers 233-403 Mhz. This is used for shipboard radars, as well as radar at airfields. You don't have to use Ghz frequencies for radar, in fact the first WWII radars used were around 100 Mhz, IIRC.

      My buddy has the exciter from a shipboard radar as his "Ham Radio" rig. This item generates 1000W CW and about 100 KW in pulse mode, which is what the radars use. It has 4 sections that each handle 1/4 of the band from 10 Khz to 1 GHz. That was then fed to a 10KW Power Amplifier and out. Just the exciter part sits in 3, 6-foot rack cabinets!

      The average pulse power in the radars is around 100,000 Watts, and can be pumped up several orders of magnitude to "burn through" jamming if necessary (peak pulse power levels around 1 GWatt!) That field is being constantly swept around the area looking for threats using phased array panels, much faster than the old "Battlezone" radars, so the RF field is effectively everywhere.

      Key fobs, RF remotes and Garage door openers are using the 330 Mhz junk band and are right in the middle of the Military A-Band. Doh! Unfortunately, they are also Part 15 users of the spectrum there, and are secondary users of those frequencies - they must not interfere and must accept any interference they experience. Double Doh!!

      • by RetroGeek ( 206522 ) on Monday July 05, 2004 @04:14PM (#9615503) Homepage
        Key fobs, RF remotes and Garage door openers are using the 330 Mhz junk band and are right in the middle of the Military A-Band

        We had rock bands come to us (near a Canadian base).

        About 3-4 miles from the hotel was a NORAD RADAR. The pulse from the RADAR would manifest itself as a "BZZT" in the band's amplifiers (If was funny seeing the band try to locate the source.....). Heck, you could hear it on your car radio.

        Big wattage is NO joke. The spill-over into other freqiencies is a fact of life (anyone with a CB will know it as cross-talk).
      • by HazE_nMe ( 793041 ) on Monday July 05, 2004 @04:55PM (#9615840) Homepage
        I work for Chamberlain who makes the Liftmaster and Chamberlain garage door openers. Our newest units just started using 420MHz. I had an old 330MHz unit and my range sucked, so I installed a 420MHz logic board and my range more than doubled. I live right next to Davis Monthan AFB which gives me all kinds of RF interference. I suggest to anyone who has trouble with their Chamberlain, Liftmaster, or Sears GDOs then call Chamberlain and find out if you can upgrade to the 420MHz boards on your model. The price of the boards is crazy expensive ($70), but we here at Chamberlain can give discounts at our leisure. We sometimes will give one out for free if the conditions are right. (WHINE, WHINE, WHINE, "But I can't afford THAT!", "$70?!, The whole unit was $150!", etc)
      • by rpdillon ( 715137 ) * on Monday July 05, 2004 @05:09PM (#9615924) Homepage
        A lot of posts to reply to, but basically, Naval Ship radars function on lots of bands, not exluding the A Band, mentioned above.

        Aircraft carriers have a good deal more power than one would think, and certainly more than a Tico, which is about medium size. One thing to note is that there is no "Medium" size for Navy ships, there are small guys, and big guys. CVN, LHD and LHA are going to have more power because they are bigger...the LHD I served on had 5 primary generators rated at 2500kW a piece, plus another 2 backups at 2000kW each. LHAs are similar, but CVNs have even more, mainly because they have fuel to burn, being nuclear.

        Oddly, in the radar category, its only the smaller ships in the Cruiser Destroyer community that have phased array radars, which have higher output than those found on other ships. On carriers, the primary high output radar is the SPS-48E (a rotating radar, as all are, with the exception of the SPY-1 series), and has such power because it is an Air Search radar that scans in 3-D. There are ranges at which we are required to turn off our radars in vicinity of land, but this is soley at the attentiveness of the watchstander, and we frequently got reports during Operation Iraqi Freedom thaty our 48E was jamming the airport radars in Kuwait, and we were requested to lower the power output.

        Anyway, a carrier pulling into town running a 48E could certainly jam such devices, but more frequently we get reports that devices start *operating* without warning (garage doors opening, etc.) Certainly you'd see these things more often if you worked on a Naval Base, since lots of ships tend to pull in and out there.
      • by Ancil ( 622971 ) on Monday July 05, 2004 @11:55PM (#9618237)

        peak pulse power levels around 1 GWatt!
        Careful with that thing. 210 MWatts more, and you could end up in the year 1955 making out with your Mom.
    • I grew up by a military base and there was a big sign at the entrance stating that certain types of radio emissions were prohibited, and I remember this from back in 1985 or so.

      Not surprised in the least, and I think it's perfectly within their rights.
  • by Jesrad ( 716567 ) on Monday July 05, 2004 @03:29PM (#9615121) Journal
    I hear you get good prices when buying tin foil in large orders. I'd probably need that for the garage door.
    • by ThisIsFred ( 705426 ) on Monday July 05, 2004 @04:00PM (#9615423) Journal
      Think again. One of the United State's largest manfacturers of aluminum products is Alcoa [alcoa.com]. They are [and their subsidiaries] also a military subcontractor. Your purchase would probably invite investigation. Now see, if you'd just been buying a little extra every week since before Y2K, you'd have enough to make an aluminum suit for you and your car for every day of the week.
    • I hear you get good prices when buying tin foil in large orders. I'd probably need that for the garage door.

      Should I file this under "missing the point"?

      Hmm...Let's remove the garage-door foil, and *then* use the remote to open it.....
  • When you can't (Score:5, Insightful)

    by dark404 ( 714846 ) on Monday July 05, 2004 @03:30PM (#9615123)
    enter your car, and start it with just the key, the government may be to blame, but you need to be slapped.
    • That doesn't help the morons who "shave" the door handles and door locks to make it all electronic. Of course, if they're dumb enough to do that then they get what's coming...
      • Re:When you can't (Score:5, Insightful)

        by WormholeFiend ( 674934 ) on Monday July 05, 2004 @03:36PM (#9615197)
        Even if they can still open the door with the key, a number of them still need the remote to deactivate the alarm system and activate the secure ignition circuit.

        My brother had one installed, and I asked him what he'd do if his remote's battery ever went dead.

        He shrugged and said he'd buy new ones at the store... but stores arent always opened when Murphy's Law decides to apply itself.
    • If you read the article, you would have realized that some of the newer cars require a wireless signal, in addition to the key, to start. While I hadn't heard of this, I'd imagine it's similar to keys with chips in them to prevent people from duplicating them . . . an electronic system working synergistically with the mechanical locking mechanism . . .
    • "enter your car, and start it with just the key, the government may be to blame, but you need to be slapped."

      Why? Because we designed the alarm system?
  • by Anonymous Coward on Monday July 05, 2004 @03:31PM (#9615129)
    Horse and buggy remains unaffected by such measures.

    • I thought that was one of the neater twists in the recent Batttlestar Galactica remake - that the only Vipers immune to the Cylon override of their control codes were the ones that had been sitting down in the Galactica museum next to the gift shop.

      That, and, of course, the über-hot Cylon chicks...

  • Forget part 15... (Score:5, Interesting)

    by irving47 ( 73147 ) on Monday July 05, 2004 @03:31PM (#9615132) Homepage
    Too bad part 15 of the FCC's guidelines can't apply. The whole "may not cause harmful interference" section might have been nice. My dad parked on a Navy base with his keyless entry-equipped Oldsmobile for a few years up in Washington. Whatever they had running was so strong, it completely fried the system.

    • Re:Forget part 15... (Score:5, Informative)

      by SagSaw ( 219314 ) <slashdot@[ ]ss.org ['mmo' in gap]> on Monday July 05, 2004 @03:41PM (#9615240)
      Too bad part 15 of the FCC's guidelines can't apply.

      No, not really. The purpose of Part 15 in this case is to protect the military (or whatever individual/group/organization is assigned the particular frequency(s)) from interfearance that your keyless entry system might produce. It is not meant to protect your keyless entry system from others who may be using their assigned spectrum properly.

      • Re:Forget part 15... (Score:5, Informative)

        by LostCluster ( 625375 ) * on Monday July 05, 2004 @03:56PM (#9615391)
        Part 15 is the part that specifies the power limits for non-licensed users to protect the licensed users.

        So, it all comes down to what frequencies the car alarm makers are expecting to use. If they pick a miliatary frequency and are trying to use it at low power, then they can't really complain when a miliatary ship comes by and blows them out of the water bandwidth-wise. However, if they pick a frequency open to the public like the 900mHz band, then it's the military transmitting too strong on a low-power band, even if it's just the result signal splash from their attempt to use their assigned band at high power.

        So, in a sense, Part 15 does protect your keyless entry system from the miliatary. They're supposed to keep their RF operations away from your space just as much as you're supposed to stay away from theirs.
    • Re:Forget part 15... (Score:4, Interesting)

      by swdunlop ( 103066 ) <swdunlop AT gmail DOT com> on Monday July 05, 2004 @03:45PM (#9615297) Homepage
      It also must accept harmful interference.. So.. They're both in the wrong. ;)
    • by M. Silver ( 141590 ) <(silver) (at) (phoenyx.net)> on Monday July 05, 2004 @04:25PM (#9615611) Homepage Journal
      Too bad part 15 of the FCC's guidelines can't apply.

      It should, just not in the way you're thinking:

      Whatever they had running was so strong, it completely fried the system.

      That's what the "must accept interference" part comes in.

      Of course, the idea of going to Olds and saying "Your stuff violated part 15 because it didn't accept FCC-legal interference. So replace it with something that does, or I'm siccing the FCC on you!" is probably not terribly workable.

      Might be fun, though.
  • This reminds me of that movie Minority Report...
  • Stratcom Jamming (Score:5, Interesting)

    by Anonymous Coward on Monday July 05, 2004 @03:33PM (#9615153)
    I used to work with an engineer who was a former air force tech on the Looking Glass. The Looking Glass missions were a group of USAF command/control aircraft that was always airborne to provide a redundant facility to the Strategic Air Command (SAC) in the unlikely event SAC ceased to exist from a USSR strike.

    He explained on several occasions that one of their amusements was lowering a long antenna and jamming garage door frequencies and other civilian applications (e.g. keyless door locks). I couldn't imagine why the air force would want to interfere with garage doors and he never had a good explanation other than they were told to do that and the crew always found it amusing.

    Urban legend? Looking Glass crew tall tale told to amuse their friends? Who knows, but they certainly had the ability to try and lord knows many friends have had their garage doors open by themselves in the middle of the night.
  • Jams? (Score:5, Insightful)

    by HotNeedleOfInquiry ( 598897 ) on Monday July 05, 2004 @03:33PM (#9615156)
    Jamming is a deliberate "denial of service" attack in the RF relm. Interference is the unintentional degradation or stoppage of service.

    When 2 ethernet NIC's transmit at the same time in normal operation we don't call it jamming. I doubt that what the government is doing is intentional.
    • Re:Jams? (Score:4, Interesting)

      by LostCluster ( 625375 ) * on Monday July 05, 2004 @03:58PM (#9615408)
      Intent doesn't really matter in the RF relm. If you're radiating whether you know it or not you're reponsible for keeping your signal source within it's authorized bounds. Signal splash to the point that it exceeds the unlicensed power limit on any band is illegal... and there's no exceptions to that.
      • Re:Jams? (Score:5, Insightful)

        by kevlar ( 13509 ) on Monday July 05, 2004 @04:06PM (#9615462)
        The military is operating within its authorized bounds. So are these remotes. The problem is that the military has blankey control over that spectrum, where as your remote can use it, but cannot interfere with anything else. Hence the "must accept any interference" clause.
        • Re:Jams? (Score:5, Informative)

          by LostCluster ( 625375 ) * on Monday July 05, 2004 @04:12PM (#9615489)
          Being the "primary users" of bandwidth space gives you the right to jam out everybody else... "secondary users" are those whose use is tolerated but they must accept any interference from the primary users and shutdown if they're bothering any primary user.

          The car entry system makers picked a frequency that belonged to the military as the primary user... they can't really complain when the military comes to town and wants to use their channel.
        • Re:Jams? (Score:5, Funny)

          by evilviper ( 135110 ) on Monday July 05, 2004 @04:21PM (#9615565) Journal
          the military has blankey control

          I know that was just a typo, but I nearly wet myself laughing, anyhow...

          Somehow I picture Linus (the "Peanuts" character) as the captain of an aircraft carrier, exerting his "blankey control".
      • Re:Jams? (Score:5, Informative)

        by Mister Transistor ( 259842 ) on Monday July 05, 2004 @04:14PM (#9615498) Journal
        Actually there are a couple of exceptions, one is in emergencies, and the other is *gasp* the military.

        The generally held concept for emergencies is "anything goes", but you better be prepared to answer for and justify your actions later on.

        The other is the military. They don't have "band limits" on their signals. They have generally decided on a band plan that doesn't interfere with other services, but any frequency that is not desginated as broadcast, amateur or public service is subject to them usurping any time at their discretion. Even some of the amateur frequencies are primarily military designation and amateurs are secondary users (parts of 440 Mhz and others).

        At the risk of being flamebait, remember, they're the U.S. Government and they can do whatever the hell they want.

  • by stoneymonster ( 668767 ) * on Monday July 05, 2004 @03:34PM (#9615159) Homepage
    "But unlike other more powerful radio signals, keyless entry remotes are not licensed by the Federal Communications Commission. They are allowed to operate on frequencies used by licensed customers as long as their signals are sufficiently weak and don't interfere with others. But because of this outlaw status, their own signals can be jeopardized." Tough. Get licensed, or have a working backup system that doesn't depend on radio. I honestly don't see the issue here. The situation isn't likely to change, so the unlicensed folk will have to work around it. Use spread-spectrum at low power or frequency hopping to get around this. -C
  • Conspiracy! (Score:5, Funny)

    by pyrrhonist ( 701154 ) on Monday July 05, 2004 @03:35PM (#9615173)
    This will be in Michael Moore's next film. </satire>
  • hmm (Score:5, Interesting)

    by HBI ( 604924 ) on Monday July 05, 2004 @03:35PM (#9615178) Journal
    I happen to work at a base where the US Army Communications Electronics Command (CECOM) [army.mil] is headquartered. I have a keyless entry. So do many of the thousands of other people who work there. Never heard of a keyless entry problem.

    • From the article:
      Some of the devices that have failed in Waldorf operate on a frequency of 315 megahertz. Another common keyless entry frequency is 302 MHz. Both of these frequencies fall within a range licensed primarily for use by the military and the federal government.
      In a summary of radio spectrum use from the National Telecommunications and Information Administration, the frequencies in the range from 225 MHz to 328.6 MHz "are heavily used worldwide for critical military air traffic control and ta
      • by HBI ( 604924 )
        Perhaps, but it just seems weird. There is a lot of comms activity going on there and nearby. If something was going to interfere, i'd expect it to crop up there. Houses butt up against the base, the whole area is prime real estate.
    • Well don'cha feel big, bro? Howd'ya come 'cross dis' information?

      (No way am I posting this with my account. [And please do notice the play on words before modding this -1.])
  • At my last base, one day I was riding in a coworker's car on the way to our office. The road there wraps around a runway. His radar detector goes apeshit when going past there. Possibly due to ILS radio waves.

    The cops at the gate don't like to see radar detectors anyway, so it was usually best to keep it off the dash after you passed through, as it was useless.

    On the other hand, keyless remotes didn't pose too much of a problem.
  • I rented a Merc over the weekend. Very nice, but there is no actual key. There is a keyhole on the door, but they didn't give me a key, just the electronic thingy. No thingy, and you can't get in the door or disarm the alarm.

    Same for the ignition, but that is perhaps less vulnerable to interference as the key dongle must be placed inside a slot.

    These cars do work in the vicinity of significant ground radar. Otherwise people at the airport would have problems. I really don't know how the lock receivers c

  • Garage door remotes (Score:5, Interesting)

    by scum-e-bag ( 211846 ) on Monday July 05, 2004 @03:36PM (#9615186) Homepage Journal
    A few years ago a US ship visited my hometown Hobart/Ausralia and garage door remotes all over the city stopped working. The US Navy apologised.
  • by crovira ( 10242 ) on Monday July 05, 2004 @03:36PM (#9615192) Homepage
    for that purpose deserves to be bitch-slapped.
  • In Eastern Europe... (Score:5, Interesting)

    by rasafras ( 637995 ) <tamas AT pha DOT jhu DOT edu> on Monday July 05, 2004 @03:36PM (#9615194) Homepage
    ...people don't interfere with it per se. Thieves armed with a laptop will nab your opener code at a gas station, and then follow you to a hotel or wherever your destination is. They steal the car at night, and are long gone with 3-4 hours head start. They're nice and useful, I'm sure, but not always appropriate.
    • That would only work if the system sends the same code every time (or if the same code can be used twice within a short period of time). IIRC, most current systems use "rolling-codes". In other words, the transmitter and receiver both contain a similar pseudorandom number generator. When you push the button, the transmitter sends the next number from the generator. The receiver then checks to see that the code received is one of the next n numbers in the sequence (this way, it still works if you press t
    • The manufacturers anticipated this, and use (admittedly less-than-perfect) countermeasures. While the details vary from make to make, the following scheme is typical:

      The key fob and auto receiver use "rolling codes". Once the vehicle accepts a code as valid, it increments to the next code in the sequence. Likewise, each time the fob is pressed it increments to the next code in the sequence. The vehicle allows, say, +5/-0 codes in the sequence to allow for missed button presses. It will never open for the s

  • A story (Score:4, Interesting)

    by iamdrscience ( 541136 ) on Monday July 05, 2004 @03:36PM (#9615196) Homepage
    My Dad was in the Navy years and years ago and apparently the radar on aircraft carriers is powerful enough to knock birds out of the air at a few hundred feet. One time a bunch of his repair crew buddies were doing work on one of these, so they turned it off and took out the fuses to ensure that it would not get turned on. While they're up working on the dish some guy comes along, sees it's not working and decides to put the fuses back in and turn it on. The guys are up there when it slowly starts to turn -- one of them jumps and slides down off the platform, and the other guy ducks the dish when it swings around and slides down after. I don't know what happened after that, but I bet the guy that put the fuses back in did not have a great time.
    • Re:A story (Score:5, Interesting)

      by hughk ( 248126 ) on Monday July 05, 2004 @03:44PM (#9615283) Journal
      There was an incident at AT&T sometime ago involving people (riggers) working on the long distance microwave links. In those days, they weren't so careful about microwave radiation - the riggers had numerous problems ranging from eye problems through to sterility.

      I am suprised at your story though. Navy procedure for radio links involved the fuses being put in control of the watch officer who ensures that they don'tr get returned until after everyone is down.

    • Re:A story (Score:2, Interesting)

      by DAldredge ( 2353 )
      Some Navy ships can pump over 6,000,000 Million watts out their rader. And it can be focused on a small area, IOW it can be used as a weapon if need be.
    • This is why you lock out the device when you are working on it.
      I find it hard to believe that such a dangerous piece of equipment doesn't have a lockout method.

      Every worker should have their own personal lock on a machine when they are working on it. They even make these funny looking multilock adapters that will allow you to have multiple padlocks on at the same time.
      • by Beardo the Bearded ( 321478 ) on Monday July 05, 2004 @04:35PM (#9615675)
        Here's a scary story:

        I worked at a branch of the military for a while. During one of the status reports, I heard this story:

        Two repair techs lock out the machine they're working on with padlocks and put the keys in their respective pockets. Once they're done the repair, they go to turn the lockout off, and...

        "What the [pretty flowers]? The [fluffy bunnies] padlocks are [cute kitten] missing!"

        They searched the ship, and they found a drawer full of bent, broken, and damaged padlocks. It didn't belong to anyone, but it was a real WTF moment. Not only did someone ignore the lockout routine, but the guy pried open the padlocks to turn the locked out machine on.

        They never found out who did it.
    • Re:A story (Score:5, Informative)

      by Holi ( 250190 ) on Monday July 05, 2004 @04:28PM (#9615627)
      In the Navy they use a system called a Red Tag systems. When you are working on equipment and you must kill the power to it you put a Red Tag on it and anyone who violates a red tag suffers severe consequences (up to court martial) So if your dad did not tag the fuse box and decided to work on the radar system (live radar will kill you if you stand in front of the dish) he was not following navy procedure.

      I've seen the outcome when the Red Tag procedure is not followed, it cost a friend of mine his hand.
      • Re:A story (Score:3, Informative)

        by alienw ( 585907 )
        It's not just the navy, it's a standard ISO safety practice, called Lock out/Tag out. Obviously, very important when working on dangerous equipment.
  • While some frustrated motorists blame aliens

    Who else in the world would blame aliens because they cant open their garage door.
    • by mfh ( 56 )
      > Who else in the world would blame aliens because they cant open their garage door.
      If you want to really know, try this guy [virtuallystrange.net].
  • semi-dupe (Score:4, Informative)

    by Anonymous Coward on Monday July 05, 2004 @03:37PM (#9615202)
    this topic has already been covered here. [slashdot.org]
  • by Zorilla ( 791636 ) on Monday July 05, 2004 @03:41PM (#9615235)
    Radar Tech: "Sir. The car keys, sir. They appear to be... jammed."

    Dark Helmet: "Jammed? Raspberry. There's only one man who would dare give me the raspberry. Lone Starr!"

  • Eckerd drugstore (Score:3, Interesting)

    by suprax ( 2463 ) on Monday July 05, 2004 @03:41PM (#9615242)
    This exact same thing happens at a local Eckerd drugstore here in NY. Anywhere in the parking lot you are unable to use your keyless entry to unlock your car. You can be inches away and it just does not work for anyone, ever.

    Although once your inside the car it will usually work, since your right on top of the receiver. It probably has something to do with Eckerd transmitting store information to a national databse or something.
  • by infernalC ( 51228 ) <matthew,mellon&google,com> on Monday July 05, 2004 @03:42PM (#9615264) Homepage Journal
    Tin-foil key fob covers... patent pending.
  • I served 8 years at Camp Pendleton CA and never saw anything like this. Of course the Marine Corps isn't really into high tech :)
    Now I did laugh every time there was a ceremony on base with a 21 gun salute and car alarms would go off left and right.
  • Hmmm.... (Score:3, Funny)

    by bfg9000 ( 726447 ) on Monday July 05, 2004 @03:44PM (#9615281) Homepage Journal
    I hear the military is why Windows keeps crashing too. At least, that's what my Microsoft Rep just told me.
  • by igrp ( 732252 ) on Monday July 05, 2004 @03:52PM (#9615361)
    ... or on the quality of the keyless entry system used, for that matter.

    One of those shows that copy MTV's Punk'd concept did a thing like this with retail CB walkie-talkies. They went to one of the big parking lots downtown and when a car's owner approached his vehicle, they just hit the speak button on the CB radio and held it down. Then, when the car wouldn't open, they'd send a fake locksmith in who'd pretend to mess with the lock for a while, eventually give up and then offer to smash in one of the windows.

    In most cases, that one walkie-talkie was enough to "jam" the keyless entry system. The only cars it failed to work on were Mercedes, BMW and IIRC Audi models (maybe imports use a different frequeny - I dunno).

    Surprisingly, most of the people couldn't seem to figure out how to get in their cars without the remote (well, at least, of those people they showed). I sometimes wonder how those people manage to put their pants on in the morning.

    • I know that some of the Mercedes models use infrared signals rather than radio. Infrared should be able to avoid most interference.
    • As the article points out, some cars are designed in such a way that even if you could get inside the car with the old fashioned key, the engine would be locked unless you transmitted the unlock signal within seconds of trying to start the car. Therefore, even if they could get in it wouldn't do them much good.
  • by Anonymous Coward on Monday July 05, 2004 @03:54PM (#9615374)
    I used to work in a lab where we did some (non-military, non-secret) radio work and it would sometimes cause problems in the car park. The problem seems to be that the receivers in the cars are built "on the cheap" using ceramic resonators rather than quartz crystals, so they are not very selective. That is, rather than being sensitive only to the frequency that the remote is transmitting on, they are also sensitive to adjacent (and not so adjacent) frequencies. They could easily be swamped by a powerful transmitter several MHz away, whereas a better-designed receiver would be imune. So I blame the remote manufacturers.

    The particular frequencies used depend on where in the world you are; the U.S. uses one set and the rest of the world uses another. Here in the "rest of the world" most remotes operate at 433 MHz. This is not far from TV frequencies - ever find your car remote doesn't work if you're parked next to a TV transmitter? Newer systems will probably be using 868 MHz (rest of world) or 913 (U.S.); this bit of the spectrum is better regulated and it would be difficult to get away with not using a crystal-based receiver. So hopefully these problems will go away.
    • by pe1chl ( 90186 ) on Monday July 05, 2004 @06:10PM (#9616280)
      Actually, 433 MHz is in a band allocated to amateur radio (HAM radio) and radiolocation (radar and positioning equipment).
      Unlicensed lowpower devices are allowed to use a small part of this band, but they have to accept interference from the other services.

      Many radio amateurs are allowed to output about 100 Watts at this frequency, which of course completely swamps the milliwatt signal of the car keys.
      The radio location service can output megawatts of pulse power.

      The frequency is also used by many other lowpower wireless devices. Interferences is very often a problem. Don't buy products using this technology.
  • by earthforce_1 ( 454968 ) <{moc.oohay} {ta} {1_ecrofhtrae}> on Monday July 05, 2004 @03:56PM (#9615395) Journal

    that went bezerk for almost 48 hours. It worked perfectly until out of the blue, the alarm would sound, doors would lock and unlock every second, and if I shut it off, it would turn itself on again a second later. The car was parked in my parents driveway at the time. I had to disconnect the battery to shut the damned thing off. I tried it again 24 hours later, same problem. The day after that, the problem went away, never reappeared.

    Co-incidentally, there was an airshow on in town during this time. When the airshow ended, so did the problems. I wonder what kind of super radar they were using that had this effect.

    • by LostCluster ( 625375 ) * on Monday July 05, 2004 @04:17PM (#9615538)
      Your car most likely trigged whenever it heard a wrong sequence on its frequency, figuring that somebody was trying to steal the car by trying to guess the code.

      When the air-show came to town, there's usually some military aircraft included in the group whose favorite comminication frequency just happens to be the one your car alarm is tuned to.

      Therefore, the car alarm thinks it's always being challenged by the random noise that is really the pilots talking to each other...
    • I have fun with this one - One person who visits a neighbor has a car that trips the alarm is you transmit on 144.390 Mhz - Other hams will know what this frequency is - APRS (Automatic Position (or Packet) Reporting System) - I run an APRS station at home - every few minutes it digipeats some inbound packet, and off goes the guys alarm. Luckly, the guy turns out to be another HAM! We worked and fixed that one. Only happened if he parked right in from of my house - 2 houses away stopped the problem

  • by LostCluster ( 625375 ) * on Monday July 05, 2004 @04:05PM (#9615460)
    The cause of the problem is rather clear... keyless systems are Part 15-compliant flea power devices, and their makers have decided to pick radio frequencies used by the military. Since those frequencies are rarely used in most civilian areas, that bandwidth is usually in the clear. However, when a military ship is coming home, that's the frequency band most likely to be used to communicate with the base, and that's where the trouble starts...

    Why don't the car people put their systems on 900mHz, 2.4GHz, or 5.8GHz with the rest of the consumer device universe? They might have to deal with occasional interference from other things, but they can be assured that nobody will ever come in with a high-wattage use of that space that'll blow them out of the water.
  • by Anonymous Coward on Monday July 05, 2004 @04:17PM (#9615530)
    Anyone remember seatbelt interlocks? Basically, the car wouldn't start until the seatbelt was fastened. A successful lawsuit by a woman who was raped because she was unable to start her car to flee her attacker put an end to the technology. Just wait for the first person raped, robbed, or otherwise ruined because their car wouldn't permit them entrance, or because their house was afire and the children couldn't exit through the garage. Laws of unintended consequences and practices of the unthinking + wronged party = lawsuit.

    It's the American way.
    • halarious.

      she must of been in a convertable?
      or else she could of just locked her door?

      Of course I'm not a girl, and i've never been raped, and I don't drive down the highway for 100 miles because my gas pedal is stuck and the brakes don't work, mostly because i'd turn the car off after the police star chasing me..
  • My cars have those keyless entry things.

    None of you will believe me, anyways.

    One day, I parked near a friends house, around Southport/Addison (chicago). I was (at the time) driving a 1998 Black Sebring.

    When I came back to pickup my car, there was a white saturn in front of it.

    Push unlock. The headlights, and the horn on both cars flash/beep.


    Push lock. The headlights, and the horn on both flash/beep twice.



    Wow... It kept working.....

    What are the chances against that? 80 billion to 1?


    Why can't I win the lotto, instead?
  • by Animats ( 122034 ) on Monday July 05, 2004 @06:23PM (#9616337) Homepage
    Anybody with a spectrum analyzer can see what's going on in a case like this. Many advanced hams have one. Cell phone and cable TV service operations usually have one around. Even a handheld multiband radio with a signal strength meter is enough to get a clue. Ideally, you'd want one of these. [optoelectronics.com] Anybody with a sizable WLAN operation probably should have one of those around. It's not like RF interference isn't well understood.

    If you're getting interference with a keyless entry device at very short range, the interference source is probably nearby. Very nearby, like tens of meters. There's an inverse square law, remember. Somebody in that parking lot has something that's emitting.

    Sure, an Aegis battlecruser could point its phased array radar in your direction, hold the beam stationary. and send a few megawatts down a narrow beam out to the horizon, but that's unlikely. Few smaller radars have that kind of power, directionality, and steerability. You still have to have near line of sight, anyway.

    Get a directional antenna and a signal strength meter, and you'll find the source.

  • by Ralph Spoilsport ( 673134 ) on Monday July 05, 2004 @08:02PM (#9616915) Journal
    I live near the sutro tower, and my wife's unlock remote for her Audi A4 simply doesn't work.

    We complain - audi says it's not their fault, City says it's not their problem.

    When I grow an extra head from the radiation I will go to the office of the Sutro Tower people and eat one of their faces.


"Ninety percent of baseball is half mental." -- Yogi Berra