[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Tftb-help] Urgent Help need on Wavelet and

From: lui
Subject: [Tftb-help] Urgent Help need on Wavelet and
Date: Mon, 23 Jul 2007 16:06:07 +1000

Dear friends,
My name is Antony. I am a postgraudate student in the University of Queensland, Australia. I am working on some Time Frequency analysis on some radar signals. I have got two issues and I would like to see if anyone has any idea on them.
1. Wavelet Transform
I have noticed that the TF toolbox is such a powerful toolbox that is able to compute most of the TFDs, either linear, bilinear, affine and even reassigned. I have come accross a couple of papers by Hao Ling et al, that they have been using the wavelet transform for TF anaylsis on some radar applications. The reference of the papers are given as follows:

[1]   H. Kim, H. Ling, “Wavelet Analysis of Electromagnetic Backscatter Data”, Electronics Letters, Vol. 28, No. 3, pp. 279-281, Jan 1992.

[2]    H. Ling, H. Kim, “Wavelet Analysis of Backscattering Data from an Open-Ended Waveguide Cavity”, IEEE Microwave and Guided Wave Letters, Vol. 2, No. 4, Apr 1992.

In those work, the wavelet transform is defined in the frequency domain with the mother wavelet in frequency domain, and which results another exponential term when the wavelet transform is defined in time domain. Compare to the command "tfrrmsc" in the TF toolbox, the wavelet transform is defined in the time domain and by writing a = f/fo, the TFDs is resulted. Obviously the difference in the defintion resulted a different time and frequency resolution properties.
If anyone has any idea on how to Ling's Wavelet transform using exisiting tool, or if there is any exsisitng code that can do the job, please advise me. The objective is to get the same style of time and frequency resolution, the variations on different wavelet can easily be modified.
2. Baraniuk-Jones optimal kernel distribution (BJOKD)
I have come accorss another paper by Gaunaurd et al that they have been using a something called Baraniuk-Jones optimal kernel distribution (BJOKD). The details of the paper is given as follows:

[3] Gaunaurd G.C., Strifors H.C., Sullivan A., “Comparison of Time, Frequency and Time Frequency Analysis of back Scattered Echoes from Radar Targets Buried in Realistic Half-Spaces”, Ultra-Wideband Short Pulse Electromagnetics 6, Ed Mokole et al, Kluwer, pp 481-492, 2003.

In the acknowledgement the authors have give thanks to signal processing group at the Rice University. It would be appreciated if someone can give me a hand on it.
Thanks for your time and look forward to hear from you soon.

reply via email to

[Prev in Thread] Current Thread [Next in Thread]