Blogger says LF Frequency was amplified to break into car

Discussion in 'Wireless & RF Design' started by jamesg6, Apr 28, 2015.

  1. jamesg6

    Thread Starter New Member

    Apr 28, 2015
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    tjohnson likes this.
  2. alfacliff

    Well-Known Member

    Dec 13, 2013
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    not even the right frequency range. and the keys are encoded, a specific pulse code required.
     
  3. Kermit2

    AAC Fanatic!

    Feb 5, 2010
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    impact amplification using a $17 dollar sledge hammer will always work. who needs fancy smancy gadgets?
    :)
     
  4. DerStrom8

    Well-Known Member

    Feb 20, 2011
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    Did you read the article? It is claimed to basically just be a repeater that amplifies the fob's signal so that it can be read by the car. It's not the type of fob you have to press the button on either, it's for high-end cars that use proximity detection.

    TS,
    I'm not seeing anything in the article about the frequency. Where did you find that?
     
  5. alfacliff

    Well-Known Member

    Dec 13, 2013
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    and those operate near 433 mhz, not at low frequencies as mentioned in the first sentence of the post, 132.2 khz. how did the guy get the code to transmitt? a lot of bits there. a lot gets on the internet without any basis of truth.
     
  6. DerStrom8

    Well-Known Member

    Feb 20, 2011
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    I don't see anything in the article about transmitting at 132.2 kHz. As you'll see in my previous post, I was asking the OP where he got that value.

    I think you're still misunderstanding the operation of these types of fobs. The code is always transmitting. They are proximity detectors, not the type you press a button on to send the code. More realistically, the transmitter is probably in the car and the fob is simply an inductive coil tuned to resonate at a certain frequency like HID cards used to get into some buildings. The claim is that the device simply amplifies the transmitter signal (whatever the frequency may be) so that it can reach the fob, then amplifies the return signal and sends it back to the vehicle.

    It does seem awfully far-fetched though. I'm not saying that it can be done, but I think that what the article is claiming.
     
  7. alfacliff

    Well-Known Member

    Dec 13, 2013
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    in other words, they are rfid transponders, transmitting around 16 mhz and recieving from the fob Possably at 132.2 khz extremely short range. others, the kind that start the cars transmitt at 433 mhz. even the rfid ones dont have enough range even with a "Power amplifier" to work very far, the lf portion has almost no range, since the antanna is so short, they are just inductivly coupled. read the first line of the post, thats where he mentions the frequency. the one that starts with " The blogger in the new york times".
     
  8. jamesg6

    Thread Starter New Member

    Apr 28, 2015
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  9. BR-549

    Well-Known Member

    Sep 22, 2013
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    jamesg6,

    Thank you for that pdf. That is quite amazing. I believe I would turn that system off. That is a terrible security strategy. Especially for a high end car.

    Either the blogger has mis-understood or the wireless company in Switzerland has mis-understood his questions.

    You must consider the source of the blog. The ny times has relied on an "OLD" reputation for a long time.

    In key-less mode, your car requires confirmation to do certain actions, like opening the door. Your car does this by sending out a signal on 134 kHz. and asking who are you?

    Your key sends its name to the car on 312 mhz. If the name is correct, the car will comply.

    If you are outside the car and give the car the wrong name.....it will ask you again. If you don't answer the car, the car will wait and ask again in one quarter of a second. Whether you are there or not.

    The car does not know you gave it the wrong name.....it thinks that you are not in close enough range yet. That's why it keeps asking till it gets the right name.

    Depending on name length, there are only a certain number of names.

    Even limiting the number on wrong names will only delay the breech.

    Because it will still ask every one quarter second for a name.

    The girl had a 312 MHz variable name transmitter.

    Terrible security.
     
  10. DerStrom8

    Well-Known Member

    Feb 20, 2011
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    I saw the thread starters comment about the frequency, i was saying i wasn't seeing it in the article.
     
  11. #12

    Expert

    Nov 30, 2010
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    Easy fix. Just add a few more microprocessors to each car. :D
    Much better than forcing people to go to all the work of sticking a key in the lock. :rolleyes:
     
  12. wayneh

    Expert

    Sep 9, 2010
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    There was a news exposé on TV on this topic not long ago. They showed the perp walking up to a car, pointing a gizmo at it, and getting in. I didn't see anything more than the teaser.
     
  13. alfacliff

    Well-Known Member

    Dec 13, 2013
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    and here at work, someone had most employees believing that the company knew where we were at work by the rfid in our badges. I guess nobody noticed that the badge only worked a couple of inches from the badge reader.
     
    DerStrom8 likes this.
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