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Since Bluetooth operates at the 2.4 GHz with 1Mhz width and 79 channels would it be possible to Jam with a few 40 dollar routers at the 2.4 spectrum default I believe the channel width is 20MHz and there are 11 channels. So all you have to do right is make sure that every router is overlapping by minimum 1mhz to block all connections to a bluetooth connection given that the wifi has a higher power then the bluetooth connection at the connection point. I understand that this is probably not the case but I'm confused on why it doesn't work so any help would be appreciated.

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  • \$\begingroup\$ H-Hey.... Let's try to be a little ethical with our questions here... \$\endgroup\$ – KingDuken Apr 20 '18 at 16:03
  • \$\begingroup\$ haha just for pentesting reasons XD... I don't plan to use this else where Just Curious ... haha get it "Just Curious" XD \$\endgroup\$ – Just Curious Apr 20 '18 at 16:05
  • \$\begingroup\$ Within wifi and FCC spec I would say it's very hard. Wifi and FCC standard/regulation is restrict enough while bluetooth is quite robust. But if you hack the wifi firmware to make it transmit out of spec, then it could get real nasty. But if you go that path you might just hack a 2.4GHz microwave oven which, while very effective, is a bad idea in every way. \$\endgroup\$ – user3528438 Apr 20 '18 at 16:08
  • \$\begingroup\$ lol a microwave would be a terrible idea XD ... but what about directional antenna... fcc sets those strict rules based off of omni antenna so you can focus the max power with a one direction antenna right or would that still be to low power \$\endgroup\$ – Just Curious Apr 20 '18 at 16:25
  • \$\begingroup\$ So what I'm understanding here is that to make it powerful enough to actually do this unless the bluetooth signal was weak IE they were 30 some feet from the connected device it would be very hard to over power with out causing physical harm. So now my question is how does the 5000 dollar jammer capable of doing this while nothing else can? \$\endgroup\$ – Just Curious Apr 20 '18 at 16:36
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This is unlikely to work. The WiFi and Bluetooth signals will interfere with each other but you would need the wifi routers to be transmitting continuously and even then Bluetooth will probably still work until the WiFi signal power is significantly higher than the Bluetooth at the receiver.

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  • \$\begingroup\$ Reason I'm asking is I came across a question where people were talking about a 5000 dollar jammer which sounds excessive I just assumed there was a more geto (meaning this in the most litteral of terms) way to create this so called jammer. I know that Hak5 sells high powered antenna for your router nearing the legal limits set by the fcc. if you had somthing similar put some metal behind the router (hopfully not burn up your router) to increase power even beyond legal limits would that have been enough as 10 meter range. \$\endgroup\$ – Just Curious Apr 20 '18 at 16:13
  • \$\begingroup\$ "high powered antennas" are either directional or snake oil. \$\endgroup\$ – τεκ Apr 20 '18 at 16:23
  • \$\begingroup\$ hakshop.com/products/long-range-wifi-kit that antenna is 7 dbm from fcc max \$\endgroup\$ – Just Curious Apr 20 '18 at 16:26
  • \$\begingroup\$ That's an amplifier, not an antenna. \$\endgroup\$ – τεκ Apr 20 '18 at 16:31
  • \$\begingroup\$ understood but just the same you amplify a directional antenna you would get an over powered signal as long as you point it in the right general direction at 100 feet that is a ton of power. even if fcc caps the power output to 36dbm with 4 routers your should be able to do this right. or am i seriously underestimating bluetooth. Thanks for all of your help I really appreciate it \$\endgroup\$ – Just Curious Apr 20 '18 at 16:41
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There is an application note from Silicon Labs about Wi-Fi and Zigbee/Thread coexistance - very similar issue. Even though it is not exactly about Bluetooth, I think Bluetooth would be affected in the same way because it shares the same frequency.

TL;DR: yes Wi-Fi can jam other protocols when used at full power, 100% duty cycle, maximum bandwidth and minimum distance (section 3.1 of that application note).

This is mainly a concern if you are designing a device with multiple radios and all their antennas are very close together.

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  • \$\begingroup\$ Ok good to know so in a nutshell its difficult to do but can be done? \$\endgroup\$ – Just Curious Apr 20 '18 at 17:32
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Bluetooth has a Spread Spectrum frequency hopping strategy to eliminate just the form of interference you envisage. WiFi is not spread spectrum, but confined to designated channels.

Read this or this (read the whole presentation) to get some clues.

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  • \$\begingroup\$ thank you. Yes you are correct :D ... but even though bluetooth jumps through the 79 channels at like 1600 times a nano sec or what ever it was I'm suggesting blocking out the entire spectrum from 2.40 to 2.485 or what ever the full spectrum is \$\endgroup\$ – Just Curious Apr 20 '18 at 19:45

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