Generate eye diagram
specifies plot attributes for the eye diagram.
handle to the figure that contains the eye diagram. You can specify any of the input
argument combinations from the previous syntaxes.
h = eyediagram(___)
Generate Eye Diagram of Filtered QPSK Signal
Generate an eyediagram of a filtered QPSK signal.
Generate random symbols. Apply QPSK modulation to get a modulated signal.
data = randi([0 3],1000,1); modSig = pskmod(data,4,pi/4);
Specify the number of output samples per symbol parameter. Create a transmit filter object,
sps=4; txfilter = comm.RaisedCosineTransmitFilter('OutputSamplesPerSymbol',sps);
Filter the modulated signal
txSig = txfilter(modSig);
Display the eye diagram.
x — Input signal
vector | matrix
Input signal, specified as a vector or matrix.
The interpretation of
x and the number of plots depend on the
shape and complexity of
xis a real-valued two-column matrix, the function interprets the first column as in-phase components and the second column as quadrature components. The two components appear in different subplots of a single figure window.
xis a complex-valued vector, the function interprets the real part as in-phase components and the imaginary part as quadrature components. The two components appear in different subplots of a single figure window.
xis a real-valued vector, the function interprets the vector as a real signal. The figure window contains a single plot.
Complex Number Support: Yes
n — Number of samples per trace
integer greater than 1
Number of samples per trace, specified as a integer greater than 1.
period — Trace period
1 (default) | positive scalar
Trace period, specified as a positive scalar. The labels on the horizontal axis of
the eye diagram range between –
offset — Offset value
0 (default) | integer in the range from 0 to (n–1)
plotstring — Plot attributes
'b-' (default) | character vector | string scalar
Plot attributes, specified as a character vector or string scalar containing symbols.
This argument sets the plotting symbol, line type, and color for the eye diagram.
The format and meaning of the symbols are the same as in the
plot function. For example, the default value
produces a solid blue line.
h — Figure handle
Figure handle to an existing figure that contains an eye diagram, specified as a
h must be a handle to a figure
eyediagram function previously generated.
h — Figure handle
Figure handle, returned as a
Figure object. To modify properties of
this object, see Figure Properties.
Introduced before R2006a