Codec2 - Alpha Release

[KE6SLS]

As interested as I am in digital voice, I've stayed out of the D-star arena. There will be much use for the new open codec once it's fully stable .. I can see our clubs using it for linking our repeaters in the near future. The time is here NOW for open codecs so all I can say is THANK YOU!

Looking forward to tinkering with the new codec/code here.

73

[K5OKC]

...You can buy the hardware AMBE chip for about $20

...and it has a DTMF encoder/decoder built-in, plus varying speed and FEC for higher bit rates.

Half and Full Duplex versions.

It's a bargain chip.

[WA5ZNU]

And finally, as sad as it is, there is maybe 5% of the ham population that actually still builds their own stuff.... So while an open codec sounds nice, it really doesn't mean anything except to them (a very small population at best)

Let's say that it is 5% of the ham population that experiments and develops stuff. Then that list of stuff includes this:
Elecraft, FlexRadio SDR, QRP, Ham Radio Deluxe, FLDigi, CocoaModem, MultiPSK DXLab Suite, MMTTY, PSK31 mode, MFSK mode, ATV, everything TAPR does, Echolink, IRLP, ham Satellites ... for starters

Of the remaining 95% of the population, don't you think some large fraction uses at least one of these things?

[KJ4IPF]

It remains to be seen whether D-Star is an Apple II or an IBM PC.

its a Commodore

[W8QZ]

How about a compatible module I can plug into my ICOM, that'd handle both the official D-STAR (using "the chip"), as well as this new codec? Automatic and/or manual switching between modes? I'd consider myself one of the 'users' (don't have D-STAR yet because the price seems too high to me - but I do use MultiPSK!) but I really don't have the hobby time available to develop anything that complex. Until the 'dust settles' (if it ever does) being able to cover multiple modes with one radio would be a big advantage.

[KB9MWR]

[QUOTE=W8QZ;2047484]How about a compatible module I can plug into my ICOM, that'd handle both the official D-STAR (using "the chip"), as well as this new codec? Automatic and/or manual switching between modes?

I never thought of this, but I like it.

[KB1LQC]

How about a compatible module I can plug into my ICOM, that'd handle both the official D-STAR (using "the chip"), as well as this new codec? Automatic and/or manual switching between modes? I'd consider myself one of the 'users' (don't have D-STAR yet because the price seems too high to me - but I do use MultiPSK!) but I really don't have the hobby time available to develop anything that complex. Until the 'dust settles' (if it ever does) being able to cover multiple modes with one radio would be a big advantage.

I think you still run into the problem of never knowing who is using what. It would be like everyone using USB and LSB on 20M voice. We could do it but it wouldn't be pretty. It would probably be more robust to let the repeater site handle the discrimination between the two codecs and either transmit both or do something that allowed both to be used seamlessly.

[K0RGR]

I think that to be a success, this new codec will need to find a champion.

Now, since the existing DSTAR standard was a joint venture of JARL and the Japanese government, how much do you think another Japanese company will want to come out with an incompatible system?

It's possible that a manufacturer that is not associated with the Japanese might come forward. But, I think most of the major Chinese companies are already suppliers for the Japanese companies, and will be reluctant to anger ICOM. Before they can do anything, someone will have to come up with a vocoder chip that implements the codec. Or, perhaps there might be a way to use the codec on a PC with a wired connection to a DSTAR radio, but I'm not sure if anyone would be interested in buying one. Hopefully, any vocoder chip will be compatible with the AMBE chip.

I'm not certain how DSTAR repeaters work. I see indications that they merely forward the datastreams without interpretation, and I believe that's how some of the adaptations of non-ICOM repeaters work. That will make the repeaters codec-agnostic. But the big money is in the radios.

So, if Puxing or Wouxun comes out with a $100 radio that does DSTAR with the open source codec, then I think I can safely say that AMBE will eventually die. There will be the AMBE DSTAR network, and the open-codec DSTAR network, with the one using the cheapest user interface winning, eventually.
It's Betamax vs. VHS all over again... but maybe this time there will be a way to migrate from one to the other if the vocoder chip can be replaced in the ICOM boxes.

Our local club got a nice grant from a big company to buy a DSTAR repeater, so I'm about to make a major investment in AMBE codec. Therefore, as much as I would like to see this proprietary codec issue go away, I think we can wait for the patent to expire on the AMBE chip, or find a champion. According to one source I saw, DVSI patented the basic technology behind AMBE in 1988, which says that one has expired already. I don't know if there are subsequent patents on AMBE, specifically, but most likely there are.

[KB9MWR]

I'm not certain how DSTAR repeaters work. I see indications that they merely forward the datastreams without interpretation, and I believe that's how some of the adaptations of non-ICOM repeaters work. That will make the repeaters codec-agnostic. But the big money is in the radios.

Yes the repeaters don't care, they simply pass the data. They don't have the AMBE chip. The problem is all the Icom radios do, and don't have a way to decode/encode this Codec2. Till a radio has a way to deal with Codec2 is nice for PC to PC stuff, but really that is it in my mind.

The AMBE patent # 6199037, issued Dec 1997, expires Dec 2017.

Till then you can buy the chip for about $20.
http://www.dvsinc.com/products/a2020.htm
Or use the DV dongle is you aren't real good with the interface circuitry. ($200)
http://www.dvdongle.com/DV_Dongle/Home.html

[KE7VZW]

piping asterisk channels in and out of it locally, very impressive. Every bit as intelligible as my g.729 channels

looking forward to a full implementation