OpenSky and/or OpenSky2... Pennsylvania state police use it, and as another poster mentioned(I think) some systems in Las Vegas, and other sporadic systems. Would be nice to add it to DSD.
First-
Do we have the spec of the protocol, or know where/how to get it?
Failing that, do we have an idea of the basis of the protocol to reverse engineer it? Is it based enough on CDPD or something else existing to be able to figure it out?
Do we know the exact codec? It supposedly fits into 4 TDMA slots, so the bitrate is perhaps lower than the 3600 rate codecs used by D-STAR? (Opensky2 uses the AMBE+2 codec we use for DMR/etc, perhaps opensky uses the older AMBE+ codec like D-STAR?)
In any case, it is more a data protocol that happens to be carrying voice than a voice protocol. This makes the treatment more complex than most of the DSD implementations. But I think if we put our collective heads together, we might be able to get this working in DSD...
Some references:
SkyCrack - HackerspaceWiki
PENNSYLVANIA STATE POLICE RADIO IN WESTMORELAND COUNTY, PA
OpenSky - The RadioReference Wiki
Talk:OpenSky - The RadioReference Wiki
http://forums.radioreference.com/harris-ma-com-ge-ericsson-forum/34946-opensky-cdpd.html
First-
Do we have the spec of the protocol, or know where/how to get it?
Failing that, do we have an idea of the basis of the protocol to reverse engineer it? Is it based enough on CDPD or something else existing to be able to figure it out?
Do we know the exact codec? It supposedly fits into 4 TDMA slots, so the bitrate is perhaps lower than the 3600 rate codecs used by D-STAR? (Opensky2 uses the AMBE+2 codec we use for DMR/etc, perhaps opensky uses the older AMBE+ codec like D-STAR?)
In any case, it is more a data protocol that happens to be carrying voice than a voice protocol. This makes the treatment more complex than most of the DSD implementations. But I think if we put our collective heads together, we might be able to get this working in DSD...
Some references:
SkyCrack - HackerspaceWiki
PENNSYLVANIA STATE POLICE RADIO IN WESTMORELAND COUNTY, PA
OpenSky - The RadioReference Wiki
Talk:OpenSky - The RadioReference Wiki
http://forums.radioreference.com/harris-ma-com-ge-ericsson-forum/34946-opensky-cdpd.html