have built GNU Radio blocks to encode and decode DStar. These blocks use
NWDigitalRadio's ThumbDV for the vocoding. My OOT (out-of-tree) module
is at https://github.com/ac2ie/gr-ambe3000.
The DStar Decoding block is mostly complete.
The decoder prints any incoming header as well as any "slow data" in
the voice frames. (Of course the main output of the decode block is the audio stream!) A GNU Radio flow-graph for a DStar receiver is included. (See the picture below.)Of course to transmit RF with GNU Radio you need a suitable, supported RF sink, like a HackRF or Ettus Research UHD.
still a "work-in-progress". Output of my current DStar Encoder block does not
have the prepended 660-bit frame header and frame sync. The output is
also not properly terminated with a terminating sync flag. In spite of these shortcomings, a flow graph is
included that will transmit a valid voice stream that can be successfully received with a DStar receiver, it just won't have a
header or a terminating flag. I'm still working on the details of how to
implement that in GNU Radio.