ctfrbud.m

来自「Time-Frequency Toolbox,其中包含很常用的MATLAB程序」· M 代码 · 共 22 行

%CTFRBUD Butterworth time-frequency distribution.
% [TFR,T,F]=TFRBUD(X,T,N,G,H,SIGMA)
%
% computes the Butterworth distribution of a signal X. 
%  
% X     = Analyzed signal
% T     = time instant(s)          (default : 1:length(X)).
% N     = number of frequency bins (default : length(X)).
% G     = time smoothing window    (default : Hamming(N/4)). 
% H     = frequency smoothing window(default : Hamming(N/4)). 
% SIGMA = kernel width             (default : 1).
% 
% TFR   = time-frequency representation
% F     = vector of normalized frequencies.
%  
% Example :
%   x = hilbert(sin(2*pi*0.25*(1:128))+0.5*randn(1,128));  
%   g = Cwindow(9,'Hamming'); h=Cwindow(27,'Hamming'); 
%   t=1:128; [tfr,T,F]=Ctfrbud(x,t,128,g,h,3.6);
%   imagesc(T,F,tfr); axis xy; xlabel('time'); ylabel('frequency')