FFT Window Functions

The window type list for Perform FFT on Report includes the following:


Window Function

Preferred Use

Rectangular

A low dynamic range function offering good resolution for signals of comparable strength. Poor when signals have very different amplitudes. w(n)=1

Tri

A Bartlett window with the endpoints valued at zero.

Van Hann

A moderate dynamic range function, designed for narrow band applications.

Blackman

A high dynamic range function, with lower resolution, designed for wide band applications.

where a0 =(1-a)/2; a1=1/2; a2=a/2

 

Hamming

A moderate dynamic range function, designed for narrow band applications. It minimizes the maximum side lobe.

Lanczos

The Lanczos window offers a windowed form of the infinite sinc filter, providing the central lobe of a horizontally-stretched sinc, sinc(x/a) for -a £ x £ a.

Welch

This approach applies a parabola-shaped window to the frequency domain data. It is based on the Bartlett method but splits the signal into overlapping segments, which are then windowed. The intent is to balance the influence of data in the center of the function.


Related Topics 

Perform FFT on a Report

FFT Window Functions

Apply FFT to Report Functions

Perform TDR on a Report