Window functions applet

(Java 1.02 Version)


Note
This page contains a Java 1.02 applet: it should work with Netscape Navigator (version 2.0 or later) or Internet Explorer 3.0.

If you are using Internet Explorer 4.0, or Netscape Navigator 4.0 with the Java 1.1 upgrade, the applet should work, but the window plot may look untidy; try the Java 1.1 version instead.

Outline instructions

The applet plots the shape of some of the commonly-used window functions. These functions are used to reduce leakage in the determination of the frequency spectra of sampled signals, and in the design of FIR (finite impulse response) digital filters.Simply select the window function(s) you want displayed by clicking the appropriate checkbox(es). Unchecking a checkbox clears that window function from the plot.

The Hanning, Hamming and Blackman windows have fixed shapes. The shape of the Kaiser window is determined by the value of the window parameter, alpha. Enter a (non-negative) value for alpha in the text box and click the Set button. If the Kaiser window checkbox is checked, the shape of the window function for that value of alpha will be shown.

Varying the shape of the Kaiser window

Try experimenting with different values for alpha.
The values listed opposite are of particular interest.
alpha Window shape
0 Rectangular
5 Similar to the Hamming window
6 Similar to the Hanning window
8.6 Almost identical to the Blackman window

Download source code (zip Archive)

Kaiser window filter design applet | FIR filter design applet (fixed shape windows)

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