Eye diagram error

GNU Radio
1

Hello,

When I used eye diagram block (which seems to be a member of WxGUI
class),
the following error appeared:

File “/usr/local/lib/python2.7/dist-packages/baz/eye.py”, line 98, in
init
self.st = gr.message_sink(gr.sizeof_float, msgq, dont_block=1)
AttributeError: ‘module’ object has no attribute ‘message_sink’

what is the main problem?

best,
Mostafa

2

Hi Mostafa,

which GNU Radio version are you using?
GNU Radio itself (to my knowledge) doesn’t come with a dedicated eye
diagram, and it’s possible that you’re trying to use an out-of-tree
module that was meant for another version of GNU Radio.
You can try to emulate an eye diagram by using the Scope Sink, and
triggering on a signal that has an edge on every symbol center.

Best regards,
Marcus

3

Hi Marcus,

I’m using GNURadio 3.7.5.1. Under [Graphical Sinks], I have “Baudline
Sink”
, “Fast AutoCorrelation Sink” and also “Eye diagram”. It doesn’t work!

I didn’t get your hint of creating an eye diagram :frowning:

Best,
Mostafa

On Tue, Feb 17, 2015 at 9:39 PM, Marcus M. [email protected]
wrote:

Marcus
init

–

Department of Electrical Engineering
Aboureyhan Building
MMWCL LAB
Amirkabir University Of Technology
Tehran
IRAN
Tel: +98 (919) 158-7730
LAB: http://ele.aut.ac.ir/~mmwcl/?page_id=411
Homepage: http://ele.aut.ac.ir/~alizadeh/

4

Hi Mostafa,

yep, these are not GNU Radio core visualizations, but come with gr-baz.
You might be using a GNU Radio 3.6-compatible version of gr-baz instead
of one that works with GR 3.7. Make sure to install the master branch of
GitHub - balint256/gr-baz: Collection of new blocks for GNU Radio , after removing all remnants of the gr-baz
version that you have.

My hint regarding the eye diagram was just to build an eye diagram like
it’s in the books [1]: An oscilloscope that is triggered on the symbol
rate.

Best regards,
Marcus

[1]Eye pattern - Wikipedia

5

I’ll add one thing to Marcus’ recommendation: turn on persistence in the
scope widget. Then you’ve got a great eye-diagram!

Very Respectfully,

Dan CaJacob

On Thu, Feb 19, 2015 at 4:33 AM, Marcus Müller
[email protected]

6

Dan,

You can turn persistence on!? I use qt widgets, I don’t see that option
in
the Time Sink. Is this a WX only option?

v/r,
Rich

7

Sorry, that is a WX-only option for now. Sigh.

Very Respectfully,

Dan CaJacob

On Thu, Feb 19, 2015 at 3:40 PM, Richard B. [email protected]