FreeDV demodulator

From GNU Radio
Jump to navigation Jump to search

FreeDV demodulator is a GNU Radio block wrapping the codec2 library freedv_api for receiving digital voice signals.

Input is a stream of modulated signal data. Output is voice audio.


select one of the 9 signal formats. (depending upon modes enabled in the linked codec2 library)

'1600' Initial mode. 8 kHz in and out.

'700' Deprecated.

700B Deprecated.

2400A Input rate 48 kHz

2400B Input rate 48 kHz

800XA Input rate = Output rate = 8 kHz

700C Input rate = Output rate = 8 kHz

700D Input rate = Output rate = 8 kHz

'2020' low-bitrate - input rate is 4 kHz, Output rate 8 kHz

Squelch threshold
Interleave frames
Squelch Enable

Example Flowgraph[edit]

This flowgraph can be found at [1]

Grfreedv fg.png

Source Files[edit]

C++ files
Header files
Public header files
Block definition