Electronic – Wireless EEG electrode design

biopotentialbluetoothRFsignalwireless

Currently, all 'wireless' EEG systems acquire signals from electrodes which are wired to an amplifier, a filter, a digitizer and then finally a wireless module.

I want to design a system that's completely wireless, maybe using wireless sensor networks. Is it possible to transmit data wirelessly (RF or bluetooth), from the electrode itself, to a station where the amplification/filtering would be done?

I do realize the raw EEG signal from a single electrode would have a LOT of noise.

Best Answer

You can't transmit the voltage of an electrode, because that does not exist: a voltage is always between two points, so you need at least two electrodes connected to your transmitter. In practice you need three to cancel out the 'common mode' noise.

To transmit the signal, you must first filter it (to remove the ever-present 50 or 60 Hz), amplify it (to bring it in the range of the A/D converter), the convert it to digital and finally transmit it. This is doable (for someone who can design such circuits, which is far from trivial), but there is not that much advantage over a wired version.