gr-dsdcc

Author: Clayton Smith
Email: argilo@gmail.com

The goal of this project is to package DSDcc (Digital Speech Decoder) as a GNU Radio block, so that it can be easily used with software radio peripherals such as the Ettus Research USRP or RTL2832U-based USB TV tuners.

Dependencies:

• GNU Radio 3.10
• DSDcc (https://github.com/f4exb/dsdcc)
• mbelib (https://github.com/szechyjs/mbelib)

Build instructions:

mkdir build
cd build
cmake ..
make
sudo make install
sudo ldconfig

After running the above commands, "DSDcc Block" should appear under the "DSDcc" category in GNU Radio Companion, and "dsdcc_block" will be available in the "dsdcc" Python package.

The examples/rtlsdr_rx.grc flow graph demonstrates how to receive digital voice sigals using an RTL-SDR.

The block expects 48000 samples per second input, and outputs sound at 8000 samples per second. The input should be FM-demodulated (for example, with GNU Radio's Quadrature Demod block) and should be between -1 and 1 while receiving digital signals. The input signal should also be free of DC bias, so make sure you are tuned accurately, or filter out DC.

Contributions are welcome!