QT GUI Eye Sink

A graphical sink to display eye diagrams

This is a QT-based graphical sink which takes a set of a complex streams and plots them as an eye pattern. For each signal, both the signal's I and Q eye patterns are plotted. Eye patterns are 2 symbol's time long. Symbol rate must be an integer multiple of the sample rate to obtain the eye pattern. The set_title and set_color functions can be used to change the label and color for a given input number.

Trigger occurs at the beginning of each stream used to plot the eye pattern; whilst a real eye diagram would be triggered with a (recovered) symbol clock. For these reasons, triggering of noisy and/or unsynchronized signals may lead to incorrect eye pattern.

The sink supports plotting streaming complex data or messages. The message port is named "in". The two modes cannot be used simultaneously, and nconnections should be set to 0 when using the message mode. GRC handles this issue by providing the "Complex Message" type that removes the streaming port(s).

This sink can plot messages that contain either uniform vectors of complex 32 values (pmt::is_c32vector) or PDUs where the data is a uniform vector of complex 32 values.

See GUI Hint for info about how to organize multiple QT GUIs

Parameters

samp_rate

sample rate (used to set x-axis labels)

name

title for the plot

nconnections

number of signals connected to sink

parent

a QWidget parent object, if any

Example Flowgraph