Transmitting voice with Osmocom

[mad]

> A firm  from Turkey called Aselsan succeeded  to make encrypted conversation
> over GSM. It transfers the voice data  (1.2 kbit/s ) with Synthetic
> Voice Modulator technology.
> 
> http://www.aselsan.com.tr/images/dokuman/HC/AHSPD/kripto/2110/2110_whitepaper_ING.pdf
> 

Looks promising, but 1.2k and even 2.4k are _very_ low bitrates for voice transmission. Quality will be accordingly bad, probably enough for military purposes where people are trained to communicate reliable over a weak communication link by talking procedures. The 1.2k codec might be about comparable to LPC-10 at 2.4k (a guess, never testet SB-LPC) which sounds quite bad, a very artifically sounding voice not really suitable for everydays conversations.

None the less it's a very interesting possibility being able to transmit data over voice channels, this should be researched as with the traffic-branches we now have the right tools at hand.


Regards,
  Mad