It's been a while since Flex released their support for FreeDV. Walter K5WH, and I have contacted them recently and it turns out the API that it used to integrate FreeDV is open source and available here:
https://github.com/n5ac/smartsdr-dsp I really can't stretch to cover this one, I'm already working on codecs, modems, and the FreeDV GUI program. Can some one else please step up and work on getting the Flex support for FreeDV up to date? Plenty of email support available from myself for the FreeDV side and the good people at Flex for their side of the API. Thanks, David On 04/02/17 13:14, David Rowe wrote: > Thanks Glen, food for thought.... > > On 04/02/17 11:02, glen english wrote: >> ham systems , that are SNR limited, not bit rate limited, will ALWAYS be >> a better bet with a constant envelope signal, compared to a linear >> signal (non constant amplitude signal) in terms of power output power >> amplifier UTILIZATION. Utilization is the key here..... >> >> for systems that need to push a large bit rate through a narrow channel, >> there is little option but a QUAM signal. >> >> There is no disadvantage of a constant envelope signal compared to a >> linar signal with regards to multipath protection, mitigation, dopplers >> etc PROVIDING THAT the signal chain is linear on receive. >> >> That is to say, after limiting a signal, information has been thrown away. >> >> So, not to get confused with a constant envelope signal with FM demod. >> results are poor compared to using a linear demod. >> ********** >> >> David, it is worth a look at GSM >> >> GSM has a training sequence each frame and deals with multipath (up to >> the training length) very well. multipath can improve the SNR. >> >> constant envelope, non linear TX, linear RX. >> >> >> g >> >> >> >> On 4/02/2017 10:37 AM, David Rowe wrote: >>> Thanks Steve, there was error in the >> >> >> >> ------------------------------------------------------------------------------ >> Check out the vibrant tech community on one of the world's most >> engaging tech sites, SlashDot.org! http://sdm.link/slashdot >> _______________________________________________ >> Freetel-codec2 mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/freetel-codec2 >> > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Freetel-codec2 mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Freetel-codec2 mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/freetel-codec2
