Simple Squelch: Difference between revisions

From GNU Radio
Jump to navigation Jump to search
No edit summary
(Add details: What is the output; what kind of filter is used. Also, added C++ link.)
(2 intermediate revisions by 2 users not shown)
Line 1: Line 1:
[[Category:Block Docs]]
[[Category:Block Docs]]
Simple squelch block based on average signal power and threshold in dB.
Simple squelch block based on average signal power and threshold in dB. The output equals the input if the average input is >= the threshold, and zero otherwise.


This is a basic template. Please improve it.
The average is computed using a Single Pole IIR filter. It uses the magnitude squared for both averaging and for comparing to the threshold.


== Parameters ==
== Parameters ==
Line 15: Line 15:
== 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.
This flowgraph shows a Simple Squelch block in a working 2 meter receiver.
 
[[File:FunCube_2_meter_NB_FM_fg.png|800px]]


== Source Files ==
== Source Files ==


; C++ files
; C++ files
: [https://github.com/gnuradio/gnuradio TODO]
: [https://github.com/gnuradio/gnuradio/blob/master/gr-analog/lib/simple_squelch_cc_impl.cc]


; Header files
; Header files

Revision as of 19:38, 21 September 2021

Simple squelch block based on average signal power and threshold in dB. The output equals the input if the average input is >= the threshold, and zero otherwise.

The average is computed using a Single Pole IIR filter. It uses the magnitude squared for both averaging and for comparing to the threshold.

Parameters

(R): Run-time adjustable

Threshold (R)
Threshold for muting.
Alpha
Gain parameter for the running average filter.

Example Flowgraph

This flowgraph shows a Simple Squelch block in a working 2 meter receiver.

FunCube 2 meter NB FM fg.png

Source Files

C++ files
[1]
Header files
TODO
Public header files
TODO
Block definition
TODO