Difference between revisions of "WBFM Receive"

From GNU Radio
Jump to: navigation, search
(Created page with "Category:Block Docs Category:Stub Docs This is the template for the "Page-per-block Docs". This first section should describe what the block...")
 
(corrected flowgraph)
 
(6 intermediate revisions by 2 users not shown)
Line 1: Line 1:
 
[[Category:Block Docs]]
 
[[Category:Block Docs]]
−
[[Category:Stub Docs]]
+
Hierarchical block for demodulating a broadcast FM signal.
−
This is the template for the [[:Category:Block_Docs|"Page-per-block Docs"]].  This first section should describe what the block does and how to use it, using however many paragraphs necessary.  Note that the title of the wiki page should match the block's name in GRC, i.e. the one defined in the block's .grc file.  Look at the [[FFT]] Block for a good example.
 
  
−
As this is a basic template, it's also in the [[:Category:Stub_Docs|"Stub Docs category"]]. Please improve it.
+
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
  
 
== Parameters ==
 
== Parameters ==
−
(''R''): <span class="plainlinks">[https://wiki.gnuradio.org/index.php/GNURadioCompanion#Variable_Controls ''Run-time adjustable'']</span>
 
  
−
; Param 1 (''R'')
+
; Channel Rate
−
: Description of parameter, provide any tips or recommended values. Note that the name of the parameter above should match the param's label that shows up in grc (e.g. Sample Rate).
+
: Input sample rate of complex baseband input. (float)
 +
 
 +
; Audio Decimation
 +
: How much to decimate Channel Rate to get to audio. (integer)
 +
 
 +
; Deviation
 +
: FM modulation deviation. Standard broadcast FM uses 75kHz
 +
 
 +
; Audio Pass
 +
: Low pass filter rolloff frequency
 +
 
 +
; Audio Stop
 +
: Low pass filter cutoff frequency
  
−
; Param 2
+
; Gain
−
: blah blah blah
+
: Audio gain
 +
 
 +
; Tau
 +
: Preemphasis time constant (float) - typically 75e-6
  
 
== Example Flowgraph ==
 
== 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 ==
 
== Source Files ==
  
−
; C++ files
+
; Python files
−
: [https://github.com/gnuradio/gnuradio TODO]
+
: [https://github.com/gnuradio/gnuradio/blob/master/gr-analog/python/analog/wfm_rcv.py]
−
 
 
−
; Header files
 
−
: [https://github.com/gnuradio/gnuradio TODO]
 
−
 
 
−
; Public header files
 
−
: [https://github.com/gnuradio/gnuradio TODO]
 
  
 
; Block definition
 
; Block definition
−
: [https://github.com/gnuradio/gnuradio TODO]
+
: [https://github.com/gnuradio/gnuradio/blob/master/gr-analog/grc/analog_wfm_rcv.block.yml]

Latest revision as of 15:38, 20 August 2020

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

Parameters[edit]

Channel Rate
Input sample rate of complex baseband input. (float)
Audio Decimation
How much to decimate Channel Rate to get to audio. (integer)
Deviation
FM modulation deviation. Standard broadcast FM uses 75kHz
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

Example Flowgraph[edit]

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

Broadcast FM fg.png

Source Files[edit]

Python files
[1]
Block definition
[2]
Retrieved from "https://wiki.gnuradio.org/index.php?title=WBFM_Receive&oldid=7496"