Statistical eye from pulse response
The statistical eye is generated by progressively accumulating the histogram of each
VH by perturbing the ideal cursor voltage by the
inter-symbol interference (ISI) voltages defined by the pulse response.
Plot Statistical Eye from Pulse Response
Load the pulse response column matrix from a file.
Use the nonreturn to zero (NRZ) modulation scheme.
modulation = 2;
Calculate the statistical eye.
[stateye,vh,th] = pulse2stateye(pulse,SamplesPerSymbol,modulation);
Visualize the statistical eye using a color map.
cmap = serdes.utilities.SignalIntegrityColorMap; figure, imagesc(th*SymbolTime*1e12,vh,stateye) colormap(cmap) colorbar axis('xy') xlabel('ps') ylabel('V') title('Statistical Eye')
P — Pulse response
Input pulse response, specified as a column matrix. The first column contains the primary pulse response and the subsequent columns (if any) contain the crosstalk pulse responses.
N — Number of samples per symbol
positive integer scalar
Number of samples per symbol, specified as a positive integer scalar.
M — Number of modulation levels
positive integer scalar greater than or equal to 2
Number of modulation levels, specified as a positive integer scalar.
M defines the modulation scheme used in the statistical eye
M= 2, the modulation scheme is nonreturn to zero (NRZ).
M= 4, the modulation scheme is four-level pulse amplitude modulation (PAM4).
S — Statistical eye matrix
Statistical eye of the pulse response
P, returned as a
VH — Voltage histogram bin centers
Vertical voltage histogram bin centers, returned as a vector.
TH — Time histogram bin centers
Horizontal time histogram bin centers, returned as a vector.
S1 — Symbol transition histograms and crosstalk histogram
Symbol transition histograms and crosstalk histogram, returned as a 3-D
S1 is used to calculate the statistical eye