cursors

[sjl006]

Hi,

I'm currently using LabView's PSK Signal Generation to generate a BPSK signal, while using LabView's example that plots an eye diagram of the BPSK signal.

Currently, I'm using the eye diagram to plot a histogram, but I'd also like to be able to zoom into the eye diagram and then replot the histogram according to this new section of the eye diagram. I've been toggling around with the cursor properties, but I can't get what I want. Any suggestions?

I've attached the program as well. My program is just a slight modifiction to the LabView example of "MT niScope QAM Eye Diagram." I've also replaced all the QAM vis inside the example with the appropriate PSK vis.

Thank you!

Sammy

[Ayman K]

Hello Sammy,

The zoom features are implemented for user interface analysis and I am not aware of a way to get the subset of the area that is zoomed within the eye-diagram. The eye diagram graph is no different from a regular waveform graph in LabVIEW and I am sure if there is a way to implement what you want with regular graphs and charts, we could definitely implement it with the eye diagram.

It would be great if a LabVIEW expert could comment on this post to confirm whether there is a way to do the above with waveform graphs and charts.

Ayman K

[Chris_Cilino]

Hey Sammy,

There's no built in feature to accomplish what you're looking for but it is possible to write a subvi that I think would do what you need. What you would do is get a reference to your graph, then use the XScale>>Range>>All Elements. This will return the current Xaxis range. You can then use this information to build an array that contains the data of interest and then plot a histogram from your data of interest. I know this description isn't super detailed so if you'd like further info post to let us know. Thanks!

Chris C

[sjl006]

Thanks Chris and Ayman for the help. I'll try that out. You'll be hearing from me when I run into difficulties

- Sammy