shanwavf

Complex Shannon wavelet

Syntax

[PSI,X] = shanwavf(LB,UB,N,FB,FC)


Description

[PSI,X] = shanwavf(LB,UB,N,FB,FC) returns values of the complex Shannon wavelet. The complex Shannon wavelet is defined by a bandwidth parameter FB, a wavelet center frequency FC, and the expression

PSI(X) = (FB^0.5)*(sinc(FB*X).*exp(2*i*pi*FC*X))

on an N point regular grid in the interval [LB,UB].

FB and FC must be such that FC > 0 and FB > 0.

Output arguments are the wavelet function PSI computed on the grid X.

Examples

Complex Shannon Wavelet

Obtain and plot a complex Shannon wavelet. Set the bandwidth and center frequency parameters.

fb = 1;
fc = 1.5;

Set the effective support and number of sample points.

lb = -20; 
ub = 20; 
n = 1000;

Obtain the complex-valued Shannon wavelet and plot the real and imaginary parts.

[psi,x] = shanwavf(lb,ub,n,fb,fc);
subplot(2,1,1)
plot(x,real(psi))
title('Complex Shannon Wavelet')
xlabel('Real Part')
grid on
subplot(2,1,2)
plot(x,imag(psi))
xlabel('Imaginary Part')
grid on

References

Teolis, A. (1998), Computational signal processing with wavelets, Birkhäuser, p. 62.