Bluetooth protocol over wifi?

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I'm looking to implement the Bluetooth protocol over a physical Wi-Fi based transport, if that makes sense.
Basically my phone has Bluetooth, and my laptop has a Wi-Fi card (802.11a/b/g).
I know that Wi-Fi operates over the range 2.412 GHz - 2.472 GHz, and that Bluetooth operates over the range 2.402 GHz - 2.480 GHz.
I couldn't help but notice the overlap here. So my questions are:

  • What sort of low-level APIs would I need (preferably in C, on Windows) in order to send a signal out at certain frequencies on the Wi-Fi card?
  • Would I be able to implement a Bluetooth stack on top of this?

So basically, can I transmit Bluetooth using my Wi-Fi card as essentially a radio transmitter?

Thanks

martymcfly

Posted 2011-05-19T15:30:54.947

Reputation: 31

Answers

4

No, you can't do this. Bluetooth devices are typically wrapped up all in one chip. Plus, they use completely different modulation techniques. No low-level anything is going to allow you to transmit anything different, unless you are flashing the device. Even then, it may not get you much closer.

Bluetooh Modulation Information: http://www.palowireless.com/infotooth/tutorial/radio.asp and http://classes.engr.oregonstate.edu/eecs/spring2003/ece44x/groups/g9/jon_gillen/white_paper_jon.pdf

About the only thing you can share between WiFi and Bluetooth devices is the antenna. (Assuming only one device is using it at a time... don't blast 32mW into the receiver of the other radio!) The radio itself is all wrapped up into the same chip. The same is generally true for WiFi.

Brad

Posted 2011-05-19T15:30:54.947

Reputation: 112 912

Thanks for the link. Sorry, edit: didn't know you couldn't press enter in this box. I read that Wi-Fi can use DBPSK at 1 Mbps, and that Bluetooth can also use 4-DBPSK. If these modulation techniques are the same (I don't know anything about them yet), then maybe it's still possible. – martymcfly – 2011-05-19T15:40:29.947

I highly doubt it is possible. Even if it were, you're talking about writing code for devices, flashing them, writing new drivers, etc., all for a single device. Not something you could distribute to others, unless they had the exact same hardware (and likely same revision). Far easier to pick up a 50 cent Bluetooth adapter, don't you think? Or if you are integrating, there are many chips with WiFi/Bluetooth all in one. – Brad – 2011-05-19T15:46:58.103

4

Implementing the Bluetooth protocol over a physical Wi-Fi based transport does make sense!

Bluetooth high speed (v3.0) defines the possibility to use alternate MAC/PHY layers, known as AMP feature. The L2CAP and higher layer protocols from Bluetooth can be transmitted over a Wi-Fi MAC/PHY layer rather than a Bluetooth MAC/PHY layer with a resulting higher throughput. Some products are on the marked supporting this - look for 'Bluetooth High Speed', AMP or Bluetooth v3.0 support.

ZooMan

Posted 2011-05-19T15:30:54.947

Reputation: 41

1

Bluetooth and Wifi have different phy layer protocols and thats what is coded into their chips, hence you can't use one chip to transmit packets of the other protocol.

Moreover most of the chip vendors, do not expose any RF logic.

freethinker

Posted 2011-05-19T15:30:54.947

Reputation: 929

0

Technically yes but there are some things to consider such as the pre existing coding on the chip and if the chip can support Bluetooth coding as well as wifi coding, I mean if you have two separate wifi chips go ahead and try but be warned I tried and nearly killed my computer because of preexisting copyright protection coding on other parts of my pc that prevented any programs on the chip from starting until I reset the chip to factory defalts.

Donovan

Posted 2011-05-19T15:30:54.947

Reputation: 1