Data over audio - hmm...

[Cesare]

There are situations where you can't have EMF where something like chirp makes sense. I believe they have sold networks for monitoring in such situations.

 

[Darth Vader]

Its quite simple to set up a couple of 40Khz ultrasonic transducers to transmit data half-duplex.

However where this becomes useful is in underwater comms. Its still fairly limited but at 35Khz a range of around 2.5Km can be achieved but and there is always a but you can only get around 1Kbaud. O.K for simple telemetry and text or highly compressed images and data.

Cheers,

DV

 

[davidsrsb]

Remote listening to CRT TV line scan whistling was a computer security spying mechanism

 

[Chefren]

IoT.... about the most useless case of a technology looking for an application ever dreamt up!

Of course it has an application. Just ask the NSA.

 

[Lliure]

Still don't get why people are using this, that LISNR product can only achieve 1Kbps and with encryption overheads it would be nigh on useless.

Seems bizarre they are trying to develop something new when bluetooth and wifi already provide a closed infrastructure.

Security is the primary use case, as I understand it. (Also "challenging" RF environments). Using PKI you can usefully encrypt messages without needing a handshake or much overhead at all; the point of the tech is that it allows untrusted devices to communicate without necessarily opening up a network connection. The other nice use case is indoor positioning from the perspective of a client app (i.e. this isn't a beacon, rather the reverse).