Abstract
The model approximation of transfer functions using rational wavelets (or molecular decompositions) is considered. By using techniques from Hardy-Sobolev spaces it is shown that Hilbert space methods such as a modified matching-pursuit algorithm and least-squares technique can be employed to obtain good approximations in bothH 2 andH ∞ norms. Several theoretical results are given on rates of convergence when the methods are applied to delay systems and fractional filters.
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The research of the first author was supported by E.P.S.R.C.
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Dudley Ward, N.F., Partington, J.R. Rational wavelet decompositions of transfer functions in hardy-sobolev classes. Math. Control Signal Systems 8, 257–278 (1995). https://doi.org/10.1007/BF01211862
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DOI: https://doi.org/10.1007/BF01211862