On Mon, 22 Apr 2013, Bruce Perens wrote: > So, David removed the VQ. He then > applied 16 bits of FEC to the most significant bits only. So, bit errors > result in a signal that might be somewhat off but is still readable by ear. > > We end up with a fade margin comparable to SSB, where previously it took an > S7 signal to work reliably (and everyone complained).
That's crazy cool! Is there a chance that sometime down the road it can be made better than SSB as well? Perhaps 2 or 3 years out? I'm amazed at the progress so far, and it can only get better! > We can only do this because we have access to the codec internals. As far as > I'm aware, AMBE uses a data FEC scheme and several times more bandwidth, and > would not approach the robustness that we could provide using a GMSK system, > not to mention our FDM modem. I assume AMBE cost a great deal more to develop too. ;-) -- Curt, WE7U. http://wetnet.net/~we7u APRS in Search and Rescue: http://wetnet.net/~we7u/search_and_rescue.html ------------------------------------------------------------------------------ Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis & visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter _______________________________________________ Freetel-codec2 mailing list Freetel-codec2@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freetel-codec2
