pulse2stateye

Statistical eye from pulse response

Description

example

[S,VH,TH] = pulse2stateye(P,N,M) calculates and plots the statistical eye S from a pulse response P with N samples per symbol and M levels of modulation.

The statistical eye is generated by progressively accumulating the histogram of each vertical slice VH by perturbing the ideal cursor voltage by the inter-symbol interference (ISI) voltages defined by the pulse response.

[___,S1] = pulse2stateye(P,N,M) also returns the symbol transition histograms and crosstalk histogram S1.

pulse2stateye(P,N,M) calculates and plots the statistical eye to the current figure.

Examples

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Load the pulse response column matrix from a file.

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') Input Arguments

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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.

Data Types: double

Number of samples per symbol, specified as a positive integer scalar.

Data Types: double

Number of modulation levels, specified as a positive integer scalar. M defines the modulation scheme used in the statistical eye calculation.

• If M = 2, the modulation scheme is nonreturn to zero (NRZ).

• If M = 4, the modulation scheme is four-level pulse amplitude modulation (PAM4).

Data Types: double

Output Arguments

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Statistical eye of the pulse response P, returned as a matrix.

Data Types: double

Vertical voltage histogram bin centers, returned as a vector.

Data Types: double

Horizontal time histogram bin centers, returned as a vector.

Data Types: double

Symbol transition histograms and crosstalk histogram, returned as a 3-D matrix.S1 is used to calculate the statistical eye S.

Data Types: double 