WBFM Receive: Difference between revisions

Latest revision as of 18:07, 22 August 2023

Hierarchical block for demodulating a broadcast FM signal.

The input is the downconverted complex baseband signal (gr_complex).

The output is the demodulated audio (float).

Compared to WBFM Receive PLL, this one does a simple mono demodulation with deemphasis

Audio Decimation: How much to decimate Channel Rate to get to audio. (integer)

Tau: Preemphasis time constant (float) - typically 75e-6 (US) or 50e-6 (Europe)

Implementing an FM broadcast band receiver is really easy with the WBFM Receive Block.

@@ Line 10: / Line 10: @@
 == Parameters ==
-; Quadrature Rate
+; Channel Rate
 : Input sample rate of complex baseband input. (float)
 ; Audio Decimation
-: How much to decimate quad_rate to get to audio. (integer)
+: How much to decimate Channel Rate to get to audio. (integer)
+; Deviation
+: FM modulation deviation. Standard FM broadcast uses 75 kHz
+; Audio Pass
+: Low pass filter rolloff frequency
+; Audio Stop
+: Low pass filter cutoff frequency
+; Gain
+: Audio gain
+; Tau
+: Preemphasis time constant (float) - typically 75e-6 (US) or 50e-6 (Europe)
 == Example Flowgraph ==
-Insert description of flowgraph here, then show a screenshot of the flowgraph and the output if there is an interesting GUI.  Currently we have no standard method of uploading the actual flowgraph to the wiki or git repo, unfortunately.  The plan is to have an example flowgraph showing how the block might be used, for every block, and the flowgraphs will live in the git repo.
+Implementing an FM broadcast band receiver is really easy with the WBFM Receive Block.
+[[File:Broadcast_FM_fg.png|800px]]
 == Source Files ==