Filters

Class ChebyWindow

java.lang.Object

Filters.ChebyWindow

public class ChebyWindow
extends java.lang.Object

Calculates a Chebychev window for use in FOR filter design.

Author:

Doug Gillespie

Constructor Summary

Constructors

Constructor and Description
ChebyWindow()

Method Summary

Methods

Modifier and Type	Method and Description
static double	acosh(double x) Calculate acosh function.
static double[]	getWindow(int nPoint, double gamma) Calculate a Chebychev window function.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ChebyWindow

public ChebyWindow()

Method Detail

getWindow

public static double[] getWindow(int nPoint,
                 double gamma)

Calculate a Chebychev window function.

When used in a filter, the filter will generally have an odd number of taps. This function will return an even number of window values. You should use the 0th to n-2th values, which will be symmetrical about a central value of 1.0.

Parameters:

nPoint - number of points

gamma - Gamma - typically 3, get 20dB * gamma attenuation in filter stop band

Returns:

window function

acosh

public static double acosh(double x)

Calculate acosh function. Returns NaN for input values < 1

Parameters:

x - input

Returns:

cosh of values >= 1 or NaN