Idea: datatransmission using ultrasound

[Richard Franks]

On Fri, 2006-12-15 at 16:08 +0000, Ole Tange wrote:
> Apparently the Neo may be capable of transmitting ultrasound (20 KHz -
> around 45 KHz). If the Neo is also capable of receiving this (using
> the microphone) then we should be able to transmit data that way. This
> may be useful for close range network (e.g. transmit business card).
> 
> The protocol will be similar to wireless ethernet. The range will be
> similar to Bluetooth.

It's definitely a neat idea :-)

My concern though, is that the exact frequency coming out of the Neo is
determined by the physical properties of the individual handset - e.g.
if the speakers are positioned slightly differently as an artifact of
the manufacturing process.. this could affect the range/pitch which is
measurable externally.

It's possible that a Neo could calibrate itself by simultaneously
sampling the pitch it is outputting.. but then you have to factor in
other unknowns like internal resonance, or whether the microphone will
register the pitch at different levels depending on the source
orientation.

I don't know enough about audio engineering to say whether these are
relevant factors or not.. but until we are able to start testing these
things out with production models or an audiologist chimes in.. I'm more
cautious than excited about this possibility.

Even if we did have bluetooth, I still think there would be room for
this idea if it works.

Richard