How does probe level works

GNU Radio
1

Hi,

I am trying to detect the presence of primary user by energy detection.
And after searching I was advised to use probe block to do the sense.
(gr.probe_avg_mag_sqrd_f).

Can anyone explain how this works. How level() method gives the energy
level.

~Dilip

2

Hi Dilip,

Have a look at the scanoo GRC flowgraph build in GNU Radio 3.7 which
uses
the probe functions for spectrum sensing:

This is the GRC flowgraph in question:

https://raw.github.com/m0mik/scanoo/master/apps/scanoo.com_rx.grc

The ‘Function Probe’ block is used to call either the ‘level()’ or
‘unmuted()’ function in the probe_avg_mag_sqrd block. You can then
access
the value using the name of the ‘Function Probe’ block. The same
technique
applies for calling the value of the ‘Probe Signal’ and ‘Probe Signal
Vector’ blocks, however these only have the ‘level()’ function
available.

Regards,

Mike

–
Mike J. M0MIK BSc MIET
Email: [email protected]
Web: http://scanoo.com