Yaesu has been in the news recently for the digital salvo they fired over the bow of the D-STAR ship. In theory I think this is a great move, and others are praising Yaesu’s announcement. My concerns with D-STAR’s proprietary AMBE vocoder algorithm and hardware, the essentially one vendor market for D-STAR equipment (Icom), and the relatively dated and unscalable D-STAR protocol are no secret to anyone who reads this blog regularly. But looking at the Yaesu digital voice whitepaper, it’s somewhat a half-baked initiative, in my opinion, where Yaesu has a new hammer and everything looks like a nail.
Most of the paper focuses on the modulation technique of D-STAR, GMSK, and pits it against Yaesu’s (errr….. Motorola’s) C4FM. While better RF and data throughput performance can be had with better modulation techniques, the big issue with D-STAR isn’t its modulation technique, it’s the layer two protocol. Yaesu doesn’t even mention its layer two protocol and network that would presumably be used, Wires II.
Yaesu’s case for C4FM superiority beyond it being used in commercial networks falls flat. In the paper there are specifications of selected D-STAR and C4FM radios compared, with some highlighted parameters. There’s also a graph comparing various modulation techinques, but the big takeaway is D-STAR has a rate of 4800 baud versus 9600 baud for C4FM. I’ve used the somewhat archiac term of baud rather than kpbs intentionally to illustrate just how lame the comparison is. Furthermore, while D-STAR is clearly in the crosshairs of Yaesu, there is no mention of D-STAR’s 128kbs data mode or how Yaesu’s solution beats that data rate.
All in all this whitepaper and initiative which some are praising appears to me to be a rather sophomoric effort, and one more concerned with selling retreaded commercial rigs in amateur radio. Aligning amateur standards with commercial ones isn’t a bad thing especially when secondhand commercial gear can be re-purposed for amateur use, but there needs to be other compelling reasons to adopt a commercial modulation technique. Even with the best layer one modulation technique, if the layer two protocol and the supporting network is badly designed the digital voice standard is doomed for failure. Yaesu needs to be making a case for its system by explaining the entire network, how it is open and non-proprietary, and how it will scale in the future. I hope Yaesu does successfully launch a competing digital voice solution, and I hope organizations like ARRL and RSGB get involved and insure that the standard is consistent with the spirit of amateur radio. Unfortunately to me this new initiative looks like another D-STAR in the making.