Quadrature mirror filter

About: Quadrature mirror filter is a research topic. Over the lifetime, 955 publications have been published within this topic receiving 28900 citations.

Orthogonal wavelet transforms and filter banks

Abstract: Summary form only given. A new class of orthogonal basis functions that can be relevant to signal processing has recently been introduced. These bases are constructed from a single smooth bandpass function psi (t), the wavelet, by considering its translates and dilates on a dyadic grid 2/sup n/, 2/sup n/m of points, psi /sub n,m/(t)=2/sup -n/2/ psi (2/sup -n/t-m). It is required that psi (t) be well localized in both the time and frequency domain, without violating the uncertainty principle. Any one-dimensional signal can be represented by the bidimensional set of its expansion coefficients. Multidimensional signals can also be expanded in terms of wavelet bases. An algorithm for computing the expansion coefficients of a signal in terms of wavelet bases has been found, the structure of which is that of a pruned-tree quadrature mirror multirate filter bank. The construction of wavelet bases and their relation to filter banks, together with several design techniques for wavelet generating quadrature mirror filters and examples, are reviewed. >

PR-QMF design with Bernstein polynomials

Abstract: A generalized, parametric PR-QMF (perfect reconstruction quadrature mirror filter) design technique based on the Bernstein polynomial approximation is developed. The parametric nature of this solution provides very useful insights into the PR-QMF problem. Several well-known orthonormal wavelet filters, PR-QMFs, are shown to be the special cases of the proposed technique. The energy compaction performance of a few popular signal decomposition techniques is presented for AR(1) signal sources. It is shown that the QMF filter banks considered here outperform the block transforms, as expected. >

Comparative study for optimisation of causal IIR perfect reconstruction filter banks

Abstract: Comparative study for optimisation of causal infinite impulse response (IIR) filters with applications to perfect reconstruction quadrature mirror filter (QMF) banks is presented. A hybrid procedure is applied where a constrained genetic algorithm is first used to search the objective function landscape for a promising valley. Sub-optimal filter parameters are then further optimised using four different methods. These are: new GA based 'creep code', gradient based constrained Sequential Quadratic programming method and Quasi-Newton method and non-gradient based downhill Simplex method. Finally, a comparison is drawn between each of the four methods of optimisation.

A Subband Adaptive Filter with the Optimum Analysis Filter Bank

Abstract: Conventional subband ADFs (adaptive digital filters) using filter banks have shown degradation in performance because of the non-ideal nature of filters. For this problem, we propose a new type of subband ADF incorporating two types of analysis filter bank. In this paper, we show that we can design the optimum filter bank which minimizes the LMSE (least mean squared error). In other words, we can design a subband ADF with less MSE than that of conventional subband ADFs.

H2/H, Signal Reconstruction in Noisy Filter Bank Systems

Abstract: This paper investigates signal reconstruction in the multirate filter bank systems with noisy subband paths. It casts the problem of signal reconstruction into a problem of mixed H2/H, control, and uses the standard results of mixed H2/H, synthesis to design an IIR synthesis filter bank.