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Owning Palette: Correlation and Spectral Analysis VIs

Installed With: Advanced Signal Processing Toolkit

Computes the single-sided bispectrum of an input univariate time series.

Dialog Box Options

Block Diagram Inputs

Block Diagram Outputs

Dialog Box Options

Parameter	Description
Data Source	Specifies whether this Express VI reads data from a block diagram input terminal or from a file. From terminal specifies that this Express VI reads data from a block diagram input terminal. From file specifies that this Express VI reads data from a file. This Express VI can read data from waveform, WAV, or TXT files. The valid format of a TXT data file is a file that contains only a 1D real array.
File Path Configuration	Contains the following options: File path—Specifies and displays the path to the file from which this Express VI reads data. This option is available only if you select From file in the Data Source section. Ask user to choose a file each time this VI runs—Specifies whether this Express VI displays a dialog box that prompts you to select a file each time this Express VI runs. This option is available only if you select From file in the Data Source section.
Signal and Window	Displays the signal and window. Contains the following option: Display window—Specifies to display the windows that you apply to the time series.
Bispectrum	Contains the following options: dB—Specifies to return the results in decibels. The default is TRUE. Bispectrum—Displays the bispectrum.
Algorithm Settings	Contains the following options: Frequency bins—Specifies the number of frequency bins for which the VI computes the bispectrum. The resulting bispectrum is a square array. Method—Specifies the method to use in computing the bispectrum. Options include FFT (default) and AR Model. Window—Specifies the time-domain window you apply to the time series. Options include Hanning, Hamming, Blackman-Harris, Exact Blackman, Blackman, Flat Top, 4 Term B-Harris, 7 Term B-Harris, and Low Sidelobe. This option is available only when you select FFT in Method. Window length—Specifies the length of the window. A large window size leads to a small variance and a large bias of the bispectrum, and vice versa. This option is available only when you select FFT in Method. Overlap—Specifies the overlap of the moving window applied to a time series as a percentage. This option is available only when you select FFT in Method. AR order—Specifies the order of the autoregressive model. The default is 40. This option is available only when you select AR Model in Method. Method of AR Model—Specifies the method to use in estimating the autoregressive model. Options include Forward-Backward (default), Least-Squares, Yule-Walker, Burg-Lattice, and Geometric-Lattice. This option is available only when you select AR Model in Method.

Block Diagram Inputs

Parameter	Description
error in (no error)	Describes error conditions that occur before this VI or function runs.
Xt	Specifies the input time series. Xt is available only when you select From terminal in Data Source.
File path	Specifies the file path of the data you want to load.This input is available only if you select the From file option in the Data Source section.

Block Diagram Outputs

Parameter	Description
error out	Contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces.
freq bins	Returns the frequency bins at which this VI estimates the bispectrum.
Sxxx	Returns the magnitude of the single-sided bispectrum, S(f1, f2).
unit	Returns the selected engineering unit of the estimated power spectral density.

This Express VI operates similarly to the following VIs and functions:

TSA Bispectrum