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jitterTotal

Measure total jitter metric from waveform

Since R2024b

Description

[TJrms,TJpkpk] = jitterTotal(x,y,SymbolTime = t) measures the total rms and peak-to-peak jitter from input jittery waveform with specified symbol time.

Total jitter is the net jitter in a waveform. The function measures total jitter by taking the rms and peak-to-peak values of the timing error sequence.

[TJrms,TJpkpk] = jitterTotal(y,SampleInterval = s,SymbolTime = t) measures the total jitter from input jittery waveform with specific sample interval and symbol time.

[TJrms,TJpkpk] = jitterTotal(x,y,xr,yr) measures the total jitter from input jittery waveform with respect to the reference waveform.

[TJrms,TJpkpk] = jitterTotal(y,yr,SampleInterval = s) measures the total jitter with respect to reference waveform and specific sample interval.

[TJrms,TJpkpk] = jitterTotal(___,Name=Value) measures the total jitter using the Name-Value pair arguments. Unspecified arguments take default values.

[TJrms,TJpkpk,TJpdf,binEdges] = jitterTotal(___) measures the total rms and peak-to-peak jitter using the above arguments. It also estimates the probability density functions (PDFs) and bin edges for the total jitter.

Input Arguments

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Time coordinates of the jittery signal, specified as a monotonically increasing vector.

If you do not provide y, the function interprets x as edge times.

Data Types: double

Amplitude coordinates of the jittery signal, specified as a vector or as an eyeDiagramSI object.

If you do not provide x, the function assumes y is uniformly sampled at the rate specified by SampleInterval.

Data Types: double

Time coordinates of the reference signal, specified as a monotonically increasing vector.

Data Types: double

Amplitude coordinates of the reference signal, specified as a vector. If you do not provide x, yr must be sampled at the same points as y.

Data Types: double

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Example: [TJrms,TJpkpk] = jitterTotal(x,y,SampleInterval = s,Plot = on) calculates and plots the histogram of the total jitter from the input waveform defined by (x,y) and the specified sample interval.

Thresholds to separate symbol levels in the jittery waveform, specified as a vector. If you do not provide SymbolThresholds, the function calculates it from the histogram of y.

Data Types: double

Thresholds to separate symbol levels in the reference waveform, specified as a vector. If you do not provide ReferenceThresholds, the function calculates it from the histogram of yr.

Data Types: double

Sample time for uniformly sampled jittery and reference waveforms, specified as a scalar.

When you provide the time vectors of jittery and reference signals, the function ignores SampleInterval and uses time vectors instead.

Data Types: double

Symbol time for uniformly sampled jittery and reference waveforms, specified as a scalar. For clock waveforms, SymbolTime is half the of the period.

Data Types: double

Options to compare the data edge to the clock edge, specified as one of these:

  • time — Compares the closest edge times.

  • order — Compares the first edge on each set.

The function uses this argument in two scenarios only:

  • Both the measured and reference waveforms are clocks.

  • The measured waveform is a data waveform and the reference waveform is a clock waveform.

When both waveforms are data waveforms with the same pattern, the function matches the edges is based on the pattern.

Option to display histogram of random jitter, specified as true (1) or false or (0).

Data Types: logical

Bin edges for histograms used to estimate total jitter PDF, specified as a vector.

By default, the function distributes BinEdges evenly with twice the resolution of Scott's rule.

Data Types: double

Output Arguments

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Observed rms total jitter or standard deviation of the total jitter, returned as a scalar.

Observed peak-to-peak total jitter, returned as a scalar.

PDF (probability distribution function) estimates of the total jitter, returned as a vector.

Bin edges for the PDFs for the total jitter, returned as a vector.

Version History

Introduced in R2024b