4 ms·

With an off the shelf antenna, what kind of range can you spoof?

jcims 7y ago
I would suggest hardwiring it to avoid committing a federal crime. https://www.fcc.gov/general/jammer-enforcement https://www.fcc.gov/general/jammer-enforcement
- Avery3R 7y ago
  Even just the leakage might get you in trouble if there is any, it should really be done in an rf shielded enclosure.
  - i_am_proteus 7y ago
    This. If you have access to a tunnel, deep basement, or cave, these can serve.
    - express_egg 7y ago
      +1 A USRP N2X0 will spoof a phone in the same room just through leakage
      - jcims 7y ago
        This sounds like something one learns unexpectedly.
colechristensen 7y ago
I was involved in some GPS SDR research in university, and this is one of those conversations where I have reservations about participating both because of potential exporting of technology (hey guys, here are some GPS jamming tips!) and simply making doing nefarious things easier for people who found my comment. On another level it is unfortunate to feel and act suspicious and mistrusting.
- vageli 7y ago
  Imagine if someone said the same to you when you expressed an interest in this field. To the interested, this paper [0] from microsoft mentions a range of 40-50 meters with off the shelf hardware. [0]: https://people.cs.vt.edu/gangwang/sec18-gps.pdf https://people.cs.vt.edu/gangwang/sec18-gps.pdf
dazhbog 7y ago
I use a crappy antenna and I get a few meters, without any amplification. If it was going further I would use attenuators or a cage. I have the SDR streaming satellite data for 5min and it then restarts and retransmitts again. That allows units on the assembly table to get a sat lock and pass the factory test.
- StavrosK 7y ago
  Does it see the SDR as one satellite, or multiple? I guess you can just spoof as many satellites as you want, but wouldn't it be rather hard to spoof a position?
  - elfchief 7y ago
    Not the OP, but it'd see it as multiple SVs. Basically you figure out what the range would be from the SVs to whatever location you want the things to think they're at, and put out all the signals to make that happen. Spoofing a single SV is pretty useless, you have to spoof at least enough of them to give you a position solution.
- jcims 7y ago
  Do you need to slave the clock to anything?

I would suggest hardwiring it to avoid committing a federal crime. https://www.fcc.gov/general/jammer-enforcement https://www.fcc.gov/general/jammer-enforcement

Avery3R 7y ago
Even just the leakage might get you in trouble if there is any, it should really be done in an rf shielded enclosure.
- i_am_proteus 7y ago
  This. If you have access to a tunnel, deep basement, or cave, these can serve.
  - express_egg 7y ago
    +1 A USRP N2X0 will spoof a phone in the same room just through leakage
    - jcims 7y ago
      This sounds like something one learns unexpectedly.

colechristensen 7y ago

I was involved in some GPS SDR research in university, and this is one of those conversations where I have reservations about participating both because of potential exporting of technology (hey guys, here are some GPS jamming tips!) and simply making doing nefarious things easier for people who found my comment. On another level it is unfortunate to feel and act suspicious and mistrusting.

vageli 7y ago
Imagine if someone said the same to you when you expressed an interest in this field. To the interested, this paper [0] from microsoft mentions a range of 40-50 meters with off the shelf hardware. [0]: https://people.cs.vt.edu/gangwang/sec18-gps.pdf https://people.cs.vt.edu/gangwang/sec18-gps.pdf

dazhbog 7y ago

I use a crappy antenna and I get a few meters, without any amplification. If it was going further I would use attenuators or a cage. I have the SDR streaming satellite data for 5min and it then restarts and retransmitts again. That allows units on the assembly table to get a sat lock and pass the factory test.

StavrosK 7y ago
Does it see the SDR as one satellite, or multiple? I guess you can just spoof as many satellites as you want, but wouldn't it be rather hard to spoof a position?
- elfchief 7y ago
  Not the OP, but it'd see it as multiple SVs. Basically you figure out what the range would be from the SVs to whatever location you want the things to think they're at, and put out all the signals to make that happen. Spoofing a single SV is pretty useless, you have to spoof at least enough of them to give you a position solution.
jcims 7y ago
Do you need to slave the clock to anything?