Code covered by the BSD License  

Highlights from
Calculate Wigner distribution

3.66667

3.7 | 7 ratings Rate this file 19 Downloads (last 30 days) File Size: 1.75 KB File ID: #15637

Calculate Wigner distribution

by

 

19 Jul 2007 (Updated )

Calculates the 2D Wigner distribution of a complex function.

| Watch this File

File Information
Description

W = mywigner(Ex)

W = output Wigner distribution
Ex = Input electric field (MUST be a column vector

Notes:
W = Int(-inf..inf){E(x+y)E(x-y)exp[2ixy]}
E(x+y) & E(x-y) are calculated via a FFT (fast Fourier transform) using the
shift theorem. The integration is performed via a FFT. Thus it is important for the data to satisfy the sampling theorem:
dy = 2*pi/X X = span of all x-values dy = y resolution
dx = 2*pi/Y Y = span of all y-values dx = x resolution
The data must be completely contained within the range x(0)..x(N-1) & y(0)..y(N-1) (i.e. the function must fall to zero within this range).

MATLAB release MATLAB 7.4 (R2007a)
Tags for This File   Please login to tag files.
Please login to add a comment or rating.
Comments and Ratings (9)
21 Jul 2012 Charles Nelatury  
02 Jun 2012 michael scheinfeild

your delay is always half of the signal
the matrix can be too large
for chirp test the max locations should be at phase 2*f*b*t but the max is alwayes at the center

02 Jun 2012 michael scheinfeild  
13 Apr 2011 Adam Wyatt

You have to think what you are doing - given data of length N, the Wigner distribution is N^2, so clearly with N=10^5, N^2 = 10^10 - you're not going to ever be able to make such a Wigner distribution.

However, it is possible that you do not need the Wigner distribution over the whole temporal and spectral domains. Unfortunately I have not implemented this yet.

05 Feb 2011 RIPUL Ghosh

i am working on seismic data that has a total length of almost 100000 data point.When i am running wigner distribution it is showing 'out of memory'.

23 Nov 2008 VictorF Dios

The user has to add a multiplication for incr_x in order to preserve the energy of the signal.

13 Jul 2008 Herliyani Hasanah

Very good

19 May 2008 kim ngan tran  
13 Aug 2007 ashutosh singh  

Contact us