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Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device
From: |
Eric Cottrell |
Subject: |
Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device |
Date: |
Wed, 19 Mar 2008 11:38:23 -0400 (EDT) |
----- Start Original Message -----
Sent: Wed, 19 Mar 2008 07:02:08 -0600
From: Jeff Brower <address@hidden>
To: Rick Parrish <address@hidden>
Subject: Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device
> Rick-
>
> > > I am also thinking of writing a APCO P25 Voice to AMBE2000 frame
> > > converter and see
> > > if the device can decode P25 as well. This may be a general IMBE and
> > > AMBE codec.
> > >
> >
> > I hope so. I looked at this a while back. What concerned me most was the
> > AMBE2000/2020 documentation seemed to omit P25 style IMBE compatibility.
> > Compare the docs to another DVSI product - the VC55 - to see what I mean.
>
> If you're looking at low bitrate codecs for GNU radio, why use a hardware
> (dongle)
> dependent solution? You might look at MELPe, which provides 600, 1200, and
> 2400 bps,
> and can be implemented as a software solution. MELPe is a US/NATO standard
> (STANAG
> 4591). Common applications are HF radio and L band satellite apps where
> bandwidth is
> very limited.
>
----- End Original Message -----
Hello,
That would be a good idea if I was doing digital voice from scratch but I am
trying to decode IMBE and AMBE used in APCO P25 and a number of other systems
like MA/COM ProVoice and some Inmarsat stuff.
MELPe may be a great solution to get Ham Digital Voice away from IMBE and AMBE.
It may be difficult to do in the case of VHF/UHF with older P25 radios being
available surplus.
IP issues can be a minefield as the Rembrandt Technologies suit about their
ATSC patents shows. I heard that HDTV Grand Alliance made the mistake of not
having a formal patent pool and there was an informal agreement. Rembrandt got
the technology patents from AT&T which was part of the HDTV Grand Alliance and
decided to play hardball and recover the costs of buying the patents plus make
a profit.
Having dealt with companies that only release information under NDA, I can
appreciate that DVSI has their information available so a device like DV Dongle
can be made. It is not a good clean open source solution but is like the
MadWifi driver.
I would like to play with ALE and STANAG protocols someday. Thanks for the
information and I will look up more information on it.
73 Eric
- [Discuss-gnuradio] DV Dongle - AMBE USB Device, Eric A. Cottrell, 2008/03/18
- Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device, Rick Parrish, 2008/03/19
- Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device, Rick Parrish, 2008/03/19
- Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device, David I. Emery, 2008/03/19
- Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device, Rick Parrish, 2008/03/20
- Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device, Jeff Brower, 2008/03/20
- Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device, Rick Parrish, 2008/03/21
- Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device, Jeff Brower, 2008/03/21
- Re: [Discuss-gnuradio] DV Dongle - AMBE USB Device, Rick Parrish, 2008/03/21