www.pudn.com > cyclostationary_toolbox.rar > wvd.m, change:1997-11-25,size:624b


function W=wvd(S)
%
% WVD          Compute the Wigner-Ville Time Frequency representaion of 
%              a signal from its spectral correlation density
%
% USAGE
%              W=wvd(S);
%              
%              S is the scd of a signal

% File: wvd.m
% Last Revised: 25/11/97
% Created: 25/11/97
% Author: Andrew C. McCormick
% (C) University of Strathclyde

W=fft(S')';
[r,c]=size(W);

if nargout==0  
  dispW=(W(1:(r+1)/2,:));
  x=(1:c)-1;
  y=(1:(r+1)/2)-1;
  y=y/r;
  contour(x,y,abs(dispW))
  title('Wigner-Ville Time-Frequency Distribution')
  xlabel('Time/Samples')
  ylabel('Frequency * pi radians')
end