Android and Ham Radio

#31
How does the DV4Mini license their DMR implementation? I just feel like we should be able to homebrew this stuff at this point. :)

Or is it just a matter of putting an AMBE chip on a breakout board and the rest is already open source?
DMR is an open standard. Mototrbo and Hytera implant that standard with extra whizbang features on top of that. In contrast P25 I believe, while a standard, is somewhat proprietary.


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#32
How does the DV4Mini license their DMR implementation? I just feel like we should be able to homebrew this stuff at this point. :)
I think the only part that is really proprietary is DVSI's AMBE voice codec, which is used in most (maybe all?) digital systems. I'm not familiar with the DV4Mini but I assume it's either using those parts or has reversed engineered patented & copyright IP. Everything else is somewhere between open source and freely licensed from JARL, Yaesu, etc. The DMR protocol is an ETSI standard.

http://www.etsi.org/technologies-clusters/technologies/digital-mobile-radio

Motorola's MOTOTRBO is an extension of DMR, which is what most commercial surplus radios use. For example, I still have VXD radios, which are repackaged Motorola XPR models. Motorola added the IP layer to interconnect repeaters, trunking and some privacy stuff.

From a ham user standpoint the encryption stuff isn't legal anyway. The fundamental part, time slots, framing, packet definitions, that's all ETSI standards.

There's a global Motorola-based (using C-Bridges to interconnect) amateur network called DMR-MARC, which was what started it all and still is the framework for talkgroups and the database of user IDs. And if I understand it correctly, the IP Site Connect has been worked around using Brandmeister. So it's really just the AMBE stuff that's closed.

And why Yaesu decided to use it when that could have been the *one* thing they could have done differently is beyond me. But then I can't say how difficult it is to develop a new codec that works as well while also being different enough not to infringe on DVSI, so it may not be easily done.
The universe wonders what Yaesu was thinking. Basically they created a Phase 1 P25 system for hams.


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DaveInDenver

Expedition Leader
#33
Icom doesn’t do DMR they do NXDN. Kenwood does DMR on the commercial side. Yaesu not sure because they were/are affiliated with Mototola i think.
Vertex Standard is owned by Motorola but Yaesu never was. When Vertex Standard was bought they spun off Yaesu back to a stand alone company. Vertex is now pretty much defunct, I think Motorola finally renamed it Motorola Solutions. They stopped supporting my VXD radios a long time ago.

NXDN was jointly developed by Icom and Kenwood. Kenwood calls it NEXEDGE and Icom IDAS. Icom sells NXDN and P25 radios (actually most companies sell P25 radios because that's what most public services use). DMR and NXDN are sold for business and industrial radios mostly.

Kenwood does all of them, DMR, P25 and NXDN. For example the NX-5000 multi-protocol radios.

http://comms.kenwood.com/special/nx_5000/

But like I say, what a charlie-foxtrot mess of competition.
 
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#34
Icom doesn’t do DMR they do NXDN. Kenwood does DMR on the commercial side. Yaesu not sure because they were/are affiliated with Mototola i think.
Vertex Standard is owned by Motorola but Yaesu never was. When Vertex Standard was bought they spun off Yaesu back to a stand alone company. Vertex is now pretty much defunk, I think Motorola finally renamed it Motorola Solutions. They stopped supporting my VXD radios a long time ago.

NXDN was jointly developed by Icom and Kenwood. Kenwood calls it NEXEDGE and Icom IDAS. Icom sells NXDN and P25 radios (actually most companies sell P25 radios because that's what most public services use). DMR and NXDN are sold for business and industrial radios mostly.

Kenwood does all of them, DMR, P25 and NXDN. For example the NX-5000 multi-protocol radios.

http://comms.kenwood.com/special/nx_5000/

But like I say, what a charlie-foxtrot mess of competition.
Yeah because you go overseas and you add in Tetra!


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