Is it possible to mod a class 2 bluetooth device to work as a class 1 device?

Question

I have two Microcontrollers which communicate over a bluetooth link (serial link, like RN-42). So far so good. Unfortunately the device is listed as a class 2 device and I noticed that the distance is indeed very limited.

Acoordingly I was wondering if it is somehow possible to mod the chip to act as a class 1 device. Is it enough to connect the chip to a better antenna? or do I need active amplification. In case I need active amplification I would appreciate if someone could point me to some tutorial, which help me getting started.

Many thanks.

Answer 1

You need a PA (power Amp) before that Antenna. Not an easy hack but possible, it will be illegal though. (you need to get a new FCC license for it)

If you have an SMA connector, you can build a tiny board with a PA and give it a shot. PA2423 is an example of such power amplifier.

The best way, replace the whole module with a class 1 module, probably some software work is needed but will be easier, cleaner and potentially faster.

Answer 2

The only difference between a Class 2 and a Class 1 device is the power output of the antenna when licensed by the FCC.

When looking at replacement modules, Bluetooth 4.0 (LE) solutions might provide the extra distance required for your application without the Class 1 designation.