hilbertnormalize.m

一种新的时频分析方法的matlab源程序。

function [x,a]=hilbertnormalize(x,r)

% The function HILBERTNORMALIZE normalizes data using its own Hilbert transformation.
% 
% Non MATLAB Library function used is: HILBT
% First argument is required. If not passed, second argument defaults to 0.
% If flipping of data is desired r should be set to 1.
%
% Calling sequence-
% [x,a]=hilbertnormalize(x[,r])
%
% Input-
%	x	- 2-D input data x(m,n)
%	r	- flipping mode 
% Output-
%	x	- 2-D normalized data
%	a	- 2-D Hilbert envelope
%
% Used by-
% 	FA
 
% Kenneth Arnold (NASA GSFC)	Summer 2003 Initial

%----- Set default parameter	
if nargin<2
    r=0;
end

%----- Flip data if requested
if r
    x=flipud(x);
end

%----- Apply modified Hilbert transform to get an envelope
a=abs(hilbt(x));

%----- Normalize data by Hilbert envelope
x = x ./ a;

%----- Flip data back if requested
if r
    a=flipud(a);
    x=flipud(x);
end