Hi Jeroen, Again, your documentation is great, I wish I had the time to do such a thing for my code as well.
I am somewhat biased in favor of running a Gnuradio modem though, because it is SDR ready, and the implementation/ testing of a new modem is very easy. Right now, the CPU footprint of Gnuradio is much heavier than that of FreeDV, especially if the graph runs at a high sample rate, so that is the major obstacle against me pushing for a wideband frontend like the USRP. For Android phones, the main limitation is CPU. There is a very hard decision to make when creating a new application. On one hand, the Android userland is quite poor compared to GNU/Linux, on the other hand applications are much more user friendly. I loathe developing using the Android SDK due to past experiences but I think if FreeDV is to be made marketable, it should be a native Android app. Right now, I am looking into providing SD card images with a complete setup for digital voice (implemented), text messages (implemented), VoIP bridging (implemented), slow speed AX.25 (not implemented yet), APRS messages (being implemented right now) and functions for repeater control (half implemented). The setup should be able to run in both GUI mode as well as console only and be able to switch between analog/digital on demand. Analog voice is using high quality Opus and digital voice is forwarded without transcoding as Codec2 packets. More modems can be implemented in Gnuradio for e.g. DMR and D-STAR compatibility. Various proprietary aspects of parts of Android slow down development because it is hard to access certain data in the Linux container. I will have a look at your API in the next few days and see if I can use it myself. Meanwhile, the Gnuradio modems are available on Github, but the rest is not pushed yet due to time constraints. Cheers, Adrian On Sunday 05 June 2016 15:59:11 Jeroen Vreeken wrote: > Hi Adrian, > > Sounds great! > > On 06/04/2016 10:43 AM, Adrian Musceac wrote: > > So what is stopping us from doing that? Not very much apparently. All > > the bits and pieces are there already, David and Brady did a huge > > amount of work on the VHF 2400 modes, so sending a 1300 bit/s stream > > of Codec2 over the air using a standard handheld should be a breeze. > > But we might need to be able to also talk APRS to send coordinates, so > > switching between modes should be easy. > > I already did some work for APRS integration. I am calling it 'FPRS' and > sending a postion update can already be done with two data frames > (80ms), adding more stuff like direction and altitude will ofcourse add > some more. > > To get it short the protocol is binary instead of text based like APRS, > but I also made an fprs2aprs_gate which will listen for FPRS packets and > will translate them to APRS packets before sending them to the APRS-IS > network. > freedv_eth is the software I use for transmitting/receiving freedv using > soundcards and it can handle NMEA data from a GPS receiver and transmit > it together with voice and other data. It might be nice example you can > use in DroidDV. > > Very limited documentation can be found at: > http://video.vreeken.net/~dml/fprs.html > > The code (fprs2aprs_gate and freedv_eth) can be found in my eth_ar > archive: http://video.vreeken.net/~pe1rxq/eth_ar.git/ > > 73, > Jeroen PE1RXQ > > > ---------------------------------------------------------------------------- > -- What NetFlow Analyzer can do for you? Monitors network bandwidth and > traffic patterns at an interface-level. Reveals which users, apps, and > protocols are consuming the most bandwidth. Provides multi-vendor support > for NetFlow, J-Flow, sFlow and other flows. Make informed decisions using > capacity planning reports. > https://ad.doubleclick.net/ddm/clk/305295220;132659582;e > _______________________________________________ > Freetel-codec2 mailing list > Freetel-codec2@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 ------------------------------------------------------------------------------ What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic patterns at an interface-level. Reveals which users, apps, and protocols are consuming the most bandwidth. Provides multi-vendor support for NetFlow, J-Flow, sFlow and other flows. Make informed decisions using capacity planning reports. https://ad.doubleclick.net/ddm/clk/305295220;132659582;e _______________________________________________ Freetel-codec2 mailing list Freetel-codec2@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freetel-codec2
