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Owning Palette: Analog Waveform VIs and Functions, Signal Processing VIs

Use the Waveform Measurement VIs to perform common time and frequency domain measurements, such as DC, RMS, Tone Frequency/Amplitude/Phase, Harmonic Distortion, SINAD, and Averaged FFT Measurements. Examples

Note  The VIs on this palette return an error if an input waveform has a dt less than or equal to zero.

Note  The Waveform Measurements VIs presently do not accept waveforms that contain complex data.

The VIs on this palette can return general LabVIEW error codes or specific waveform error codes.

Palette Object	Description
Amplitude and Level Measurements	Performs voltage measurements on a signal.
Amplitude and Levels	Returns the amplitude, high state level, and low state level of a waveform or an array of waveforms. The data type you wire to the signal in input determines the polymorphic instance to use.
Averaged DC-RMS	Calculates the DC and/or the RMS values of an input waveform or array of waveforms. The data type you wire to the signal in input determines the polymorphic instance to use.
Basic Averaged DC-RMS	Takes a waveform or an array of waveforms in, applies a window to the signal, and averages the DC and RMS values calculated from the windowed signal with the previous DC and RMS values according to the averaging type input. The data type you wire to the signal in input determines the polymorphic instance to use.
Cross Spectrum (Mag-Phase)	Computes the averaged cross power spectrum of the input signals. Results are returned as magnitude and phase.
Cross Spectrum (Real-Im)	Computes the averaged cross power spectrum of the input signals. Results are returned as real and imaginary parts.
Cycle Average and RMS	Returns the average and RMS levels of a selected cycle of a periodic waveform or an array of periodic waveforms. The data type you wire to the signal in input determines the polymorphic instance to use.
Distortion Measurements	Performs distortion measurements on a signal, such as tone analysis, total harmonic distortion (THD), and signal in noise and distortion (SINAD).
Dual Channel Spectral Measurement	Measures the frequency response of the input signals and the coherence based on the current and previous input signals. This Express VI returns results such as Magnitude, Phase, Coherence, Real, and Imaginary.
Extract Multiple Tone Information	Returns the frequency, amplitude, and phase for each signal tone whose amplitude exceeds a specified threshold. The data type you wire to the time signal in input determines the polymorphic instance to use. If you wire an array of waveforms to time signal in, LabVIEW selects the Extract Multiple Tone Information N Chan instance by default.
Extract Single Tone Information	Takes a signal in, finds the single tone with the highest amplitude or searches a specified frequency range, and returns the single tone frequency, amplitude, and phase. The data type you wire to the time signal in input determines the polymorphic instance to use.
FFT Power Spectral Density	Computes the averaged power spectral density of time signal. The data type you wire to the time signal input determines the polymorphic instance to use.
FFT Power Spectrum	Computes the averaged auto power spectrum of time signal. The data type you wire to the time signal input determines the polymorphic instance to use.
FFT Spectrum (Mag-Phase)	Computes the averaged FFT spectrum of time signal. FFT results are returned as magnitude and phase. The data type you wire to the time signal input determines the polymorphic instance to use.
FFT Spectrum (Real-Im)	Computes the averaged FFT spectrum of time signal. FFT results are returned as real and imaginary parts. The data type you wire to the time signal input determines the polymorphic instance to use.
Frequency Response Function (Mag-Phase)	Computes the frequency response and the coherence based on the input signals. Results are returned as magnitude, phase, and coherence.
Frequency Response Function (Real-Im)	Computes the frequency response and the coherence based on the input signals. Results are returned as real part, imaginary part, and coherence.
Harmonic Distortion Analyzer	Takes a signal in and performs a full harmonic analysis, including measuring the fundamental frequency tone and harmonics, and returning the fundamental frequency, all harmonic amplitude levels, and the total harmonic distortion (THD). The data type you wire to the signal in input determines the polymorphic instance to use.
Pulse Measurements	Accepts a periodic waveform or an array of periodic waveforms and returns the period, pulse duration (pulse width), duty cycle (duty factor), and pulse center of a selected pulse and period. The data type you wire to the signal in input determines the polymorphic instance to use.
SINAD Analyzer	Takes a signal in and performs a full Signal in Noise and Distortion (SINAD) analysis, including measuring the fundamental frequency tone and returning the fundamental frequency and SINAD level in dB. The data type you wire to the signal in input determines the polymorphic instance to use.
Spectral Measurements	Performs FFT-based spectral measurements, such as the averaged magnitude spectrum, power spectrum, and phase spectrum on a signal.
Timing and Transition Measurements	Performs timing and transition measurements, such as frequency, period, or duty cycle, on a signal, usually a pulse.
Tone Measurements	Finds the single tone with the highest amplitude or searches a specified frequency range to find the single tone with the highest amplitude. You also can find the frequency and phase for a single tone.
Transition Measurements	Accepts an input signal of a single waveform or an array of waveforms and measures the transition duration (rise or fall time), slew rate, preshoot, and overshoot of a selected positive or negative transition in each waveform. The data type you wire to the signal in input determines the polymorphic instance to use.

Subpalette	Description
Waveform Monitoring VIs	Use the Waveform Monitoring VIs to analyze the waveforms for trigger points, to search for peaks, and to perform limit mask testing.

Examples

Refer to the following VIs for examples of using the Waveform Measurements VIs:

• maxmpl.llb: labview\examples\measure

   

• demos.llb: labview\examples\apps

   

• measxmpl.llb: labview\examples\analysis