Pole-zero estimation from complex cepstrum

[Tarun Pruthi <tpruthi@xxxxxxxxxxxx>]

Hi all,

I am working on the automatic detection of vowel nasalization using 
knowledge-based acoustical parameters as part of my PhD thesis work. In 
this context, I have looked at various techniques to estimate poles and 
zeros (eg. Shanks's method and various other techniques to linearize the 
zero estimation problem). Until now I haven't really found any technique 
that is very useful to locate the zeros in a nasal consonant/nasalized 
vowel spectrum.

One of the techniuqes that I only got a short description about seemed to 
be very different. This was based on the complex cepstrum. In this 
technique a derivative of the log magnitude DFT spectrum is taken to 
effectively convert the zeros of a transfer function to poles and estimate 
their locations. Even though, the approach seems interesting I haven't 
been able to locate a detailed reference for this technique.

I would be grateful if anyone could give me a reference for the paper, or 
the paper itself if possible. Also, if anyone has the code to implement it 
and is willing to share the code, please let me know. It would also be 
interesting to know your comments about the effectiveness of such 
pole-zero estimation techniques to the problem of locating zeros in the 
nasal consonant/nasalized vowel spectra.

With warm regards,
Tarun

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Tarun Pruthi
Graduate Research Assistant, ECE
Room 3180, A V Williams Building
University of Maryland, College Park
MD 20742 USA
Email: tpruthi@xxxxxxxxxxxx
Web: www.ece.umd.edu/~tpruthi
Ph: 301-405-1365
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