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Waveform Lab

 

Waveform Lab is an extended version of the Waveform Manager family that adds waveform math to all of the features found in the Waveform Manager Pro and Opt-P versions.  This package is particularly well suited to electronic design applications including instrument development, high speed communication and power system design.

Math Expressions

You perform math operations by defining new waveforms using algebraic expressions.  Waveforms are variables in these expressions.  For example, to multiply two waveforms you would define a new waveform with the expression Wfm1*Wfm2.

Built-in array variables representing time (t) and frequency (f) make it easy to define new waveforms from scratch using common trigonometric functions such as sin(2*pi*60Hz*t).  Other functions provide rectangular and triangle wave shapes.

The program supports double precision floating point arithmetic, so the numerical performance of most operations is limited only by the resolution, accuracy and noise of the waveforms you analyze.

Waveform Processing Functions

Waveform processing functions include the following general groups.

bulletCalculus
bulletComplex variable
bulletdB conversions
bulletExtraction/Concatenation
bulletFourier transform
bulletTime and Frequency transformation
bulletNormalization
bulletImpedance and reflection coefficient
bulletFilter
bulletWaveform Synthesis
bulletWaveform array reduction

For more information, download the User Manual and check out the section: "Measurement and Analysis|Lab Version|Waveform Math".

Applications

Waveform Lab facilitates electronic design and signal integrity work, enabling you to draw data from bench instruments such as scopes, network and spectrum analyzers as well as from simulation programs such as LTSpice into a common display and analysis environment.  Output waveform files to LTSpice for use in simulation.  Complex datasets can be exported in S1P or S2P format for import into Genesys.  

Most operations function with either variable or fixed time/frequency steps, so operations like integrating a noise density plot on logarithmic frequency intervals to get total noise voltage are performed easily.

Specialized functions that convert step response to/from frequency response make it possible to use your sampling scope as if it were a vector network analyzer for many applications.  Apply low pass filter functions to step response data by transforming to frequency response, applying the filter function and then transforming back to step response.  Or apply normalization operations normally associated with network analyzers to remove the effects of scope and probe from amplifier response measurements.

3D Data reduction

Waveform Lab includes provisions for analysis of 3D data sets.  One group of special functions operates column-wise across an array of waveforms so that each sample in the 2D result waveform results from samples at the same position from each waveform in the array.  These functions include:

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ArrayMax

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ArrayMin

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ArrayAvg

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ArrayStDev

Standard waveform measurements can also be used in math waveform expressions to reduce 3D data to 2D.  For example the waveform measurement

Max(wfm1)

when applied to a 3D data set of 10,000 records would produce a 2D waveform 10,000 samples long where each sample represents the maximum value found in the corresponding record in wfm1. To navigate to the source record corresponding to a feature in the result, right-click the feature in the result and choose "Find source record".

Calculation

Waveforms that depend on other waveforms for their definition are refreshed whenever one of the source waveforms changes.  It is possible to define a waveform that depends on the currently selected record of a 3D waveform, and updates when the current record is changed.

Units

Dimensional units are also managed by the program and carried into the result waveform.  For example the product of a  voltage and a current waveform would be expressed in units of "VA".  Conversion factors may be used as part of such expressions to cause the result to be displayed with desired units.  The expression Wfm1*Wfm2*1.0"W/VA" would display in units of "W".

 

Step response (top left) smoothed (bottom left) and transformed to the frequency domain, displayed on a log frequency scale (right).

 

Analysis of an ADC output by subtracting a best-fit fundamental and performing a windowed FFT on the residual.  Note that the residual contains a significant frequency component near the fundamental in the latter portion of the record indicating some FM in the sample clock.

 

TDR plot of high speed board mounted relay (left) displayed in terms of impedance (right) using the RhoToZ function.

 

3D perspective view of a 401 record data set from a spectrum analyzer.  The green and blue waveforms are ArrayMax and ArrayMin functions applied across the complete data set.

 

3D view of a 3D dataset from a spectrum analyzer.

 

Logarithmic plot of data from network analyzer with constant sample interval

 

Create user defined fields to track waveform and customer information.