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Adapting a lattice filter

Started by Lalin May 23, 2006
Hi, 
I am planning to use a lattice adaptive filter for system identification.
I am unable to find method to update the km�s in the lattice.  What have I
missed?  We can convert any FIR to a lattice and can adapt a FIR as needed.
 Why can�t we only adapt the lattice ? 
Thank you, 
Lalin 


Lalin wrote:
> Hi, > I am planning to use a lattice adaptive filter for system identification. > I am unable to find method to update the km's in the lattice. What have I > missed?
Google -> adaptive lattice filter
Hi Andor, 
I am unable to find it in google as well as in well known text books!. I
am  little puzzled about this conundrum. We can adapt a FIR as needed, can
convert the FIR to a unique lattice filter and why can�t we only adapt the
lattice? Is it because we can't find a error criteria at intermediate
stages ? 
BTW: GAL algo's use the lattice only as an orthogonalizer so they don't
count. 

Check out this link.


http://scholar.lib.vt.edu/theses/available/etd-4698-201138/unrestricted/etd.pdf

Bob Adams

>Check out this link. > > >http://scholar.lib.vt.edu/theses/available/etd-4698-201138/unrestricted/etd.pdf > >Bob Adams > >
Thank for the link, again this does not help me since, it is Gradient Lattice Algorithm(GAL)these algorithms work on joint estimation principle. The lattice filter is used as a pre-processing(Orthogonalizing unit) to do basic FIR LMS on the backward coefficients. This improves the convergence speed. I am looking for LATTICE ONLY adaptation.
> >>Check out this link. >> >> >>http://scholar.lib.vt.edu/theses/available/etd-4698-201138/unrestricted/etd.pdf >> >>Bob Adams >> >> >Thank for the link, again this does not help me since, it is Gradient >Lattice Algorithm(GAL)these algorithms work on joint estimation
principle.
>The lattice filter is used as a pre-processing(Orthogonalizing unit) to
do
>basic FIR LMS on the backward coefficients. This improves the
convergence
>speed. I am looking for LATTICE ONLY adaptation. >
Have you looked at "Adaptive Filter Theory" by Simon Haykin? I have the thrid edition and it appears that he has a good selection of various adaptive lattice algorithms. You may be able to cast your problem to fit one of the models in the book.
>Have you looked at "Adaptive Filter Theory" by Simon Haykin? I have the >thrid edition and it appears that he has a good selection of various >adaptive lattice algorithms. You may be able to cast your problem to
fit
>one of the models in the book. >
Yes, I have read/have Simons book, Sayed and Honig and many more Adaptive DSP books. This is section has been conveniently omitted from the books without giving any reason. The problem sounds very trivial but for some reason no one have solution. Thanks, Lalin