discuss-gnuradio
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Discuss-gnuradio] trouble with QAM mod/ WX GUI Constellation Sink


From: Bill Eaton
Subject: [Discuss-gnuradio] trouble with QAM mod/ WX GUI Constellation Sink
Date: Thu, 16 Jul 2015 18:23:09 -0700

I have a desire to use GNURadio + USRP to run a 16 QAM signal through an amplifier, demodulate, and calculate BER or EVM or some measure of linearity. That’s the long term goal.

 

For the short term, I thought I would take baby steps. And I got stuck trying to make pretty constellation plots. My flowgraph is below. It sort of behaves like I expect for 4 QAM, but it doesn’t do so good for 16 QAM. In the WX GUI Constellation widget, there is an option called M. Is this at all related to the number of constellation points? If so, the max is 8 and that might explain why I cannot make a nice 16 QAM constellation diagram. Is there anything else I’m doing wrong?

mlist_qam_constellation.grc.png

constellation.png

 

 


reply via email to

[Prev in Thread] Current Thread [Next in Thread]