[amsat-bb] Re: Icom D-Star
vk3jed at gmail.com
Fri Apr 22 14:58:05 PDT 2011
At 06:06 AM 4/23/2011, Gordon JC Pearce wrote:
>No, but transmission using secret codes is.
Assuming the purpose is to obscure the meaning of the message.
>How, *exactly*, does DStar work? Be sure to include a full and accurate
>description of how each frame of audio is compressed...
No need to, there is a device readily available on the market that
will decode the audio for you, complete with data sheets, so anyone
with the relevant technical knowledge can build an AMBE decoder (and
some have). The purpose of the audio coding is compression. While
the algorithm is protected by patents, and the only economic way to
license it is to buy a chip from DVSI, they are readily available, as
is the documentation. And of course, if that's all too hard, you can
simply go to your local ham store and buy a D-STAR radio (as can the
authorities), or buy a DV dongle.
Your argument doesn't make sense, and I've clearly shown that the
purpose of AMBE is not to "obscure the meaning of the message", but
to facilitate communication, with means to decode it readily
available off the shelf. I certainly don't need any encryption keys
to decode D-STAR, just the right hardware. :)
73 de VK3JED / VK3IRL
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