Jan, I see a number of potential problems with your VHF/UHF idea, most of which are compatibility issues with existing Icom repeater hardware and end-user radios; it may be possible to overcome these, but it would require working with the JARL and Icom to properly extend the D-Star protocol to handle them. Your HF ideas are rather interesting, though.
Matthew Pitts N8OHU Sent from my Verizon Wireless BlackBerry -----Original Message----- From: do1...@web.de Date: Mon, 28 Nov 2011 12:01:03 To: <freetel-codec2@lists.sourceforge.net> Reply-To: freetel-codec2@lists.sourceforge.net Subject: [Freetel-codec2] HF narrow band Hi all, @David: Great work! Now we can develop / define a <= 2200bit/s air interface for HF / short-wave DV communication. For openDV (D-Star) and other (better) DVmodes, I designed a low cost Modem-Board (DV-RPTR; www.dvrptr.de) and a stand-alone DV-Board (DV-ATRX). My wish is, to implement new powerful air interfaces on this AVR32 target and sometimes I want a fixpoint version of Codec2 running on it. My problem: I have not the mathematics background for this! It's not easy for me to optimize a GMSK demodulator for example. Maybe some people reading this have the capabilities to do this. In my thoughts: VHF/UHF (openDIGI): - using 12.5kHz bandwidh / normal FM transceivers / 8000baud C4FM modulation - repeater can transmit up to 4 DV streams in one channel - high quality / wideband mode in the case of one stream - data packets HF (unarDV, Version1 - for direct XRF connect): - using 3750baud GMSK / openDV (AMBE-2020) voice - connection to the D-Star network (reflectors) - large blocks of 240ms / interleaving - no slow-data, only Callsign data (3 parts on 3 blocks) HF (unarDV, Version2 - better): - using 2200baud GMSK - large blocks of 240ms / interleaving - Callsign data (3 parts on 3 blocks) In all air interfaces we should use TurboProductCode for the important bits of the voice data... If someone has interest to develop a powerful air interface (open source only) please contact me. With a soundcard / AVR32 based solution we can bring Codec2 in the air. Kind regards, Jan Alte, DO1FJN ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-novd2d _______________________________________________ Freetel-codec2 mailing list Freetel-codec2@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freetel-codec2 ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-novd2d _______________________________________________ Freetel-codec2 mailing list Freetel-codec2@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freetel-codec2
