It sounds obvious when you hear about it, but this one actually sounds patentable.

Bluetooth headsets to get dual mics
Aussie developers use secondary mics for noise suppression
By Bryan Betts → More by this author
Published Sunday 10th June 2007 09:02 GMT

Adding a second microphone to a Bluetooth headset significantly improves its ability to capture speech by making it more effective at noise cancellation and suppression, according to Australian audio software developer Dynamic Hearing.

The company has added a multi-mic feature called VoiceField to its Atlas audio processing software for CSR’s Bluetooth silicon. VoiceField uses two microphones, one in the usual place to capture the user’s speech, and the other located elsewhere to pick up the background noise.

The software in effect subtracts the latter from the former, leaving what Dynamic Hearing’s CEO, Dr Elaine Saunders, called “an extremely clean transmit signal”.

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