In this paper, we consider the problem of blind separation of causal minimum phase convolutive mixtures of two sources. We study in detail the so-called decorrelation approach. It consists in finding a causal minimum phase filter which, driven by the observations, produces decorrelated outputs. It is well established that this approach allows to separate the sources if the mixing filter is a no...

In this note I discuss some issues in filter design for equalization of sound systems. The emphasis is on rationale, not on experiments, and I will focus on a few common misunderstandings. I will briefly describe the basic concepts used in sound equalization, such as FIR and IIR filters, minimum and linear phase and present basic mathematical facts as well as give a background to the philosophy...

In this paper, a new family of two-channel low-delay filter banks and wavelet bases using the PR structure in [3] with SOPOT coefficients are proposed. In particular, the functions alpha(z) and beta@) in the structure are chosen as nonlinear-phase FIR and IIR filters, and the design of such multiplier-less filter banks is performed using the genetic algorithm. The proposed design method is very...

This paper presents a programmable multi-mode finite impulse response (FIR) filter implemented as switched capacitor (SC) technique in CMOS 0.18 μm technology. Intended application of the described circuit is in analog base-band filtering in GSM/WCDMA systems. The proposed filter features a regular structure that allows for elimination of some parasitic capacitances, thus significantly improvin...

In this paper, we present a new QR based algorithm for IIR adaptive filtering. This algorithm achieves a reduction of complexity with regard to the IIR-QR algorithm by using a block reduction transformation. Moreover, this new approach make it possible to directly transform fast FIR algorithm into fast O (N) versions of the IIR algorithm. Therefore, we derive a fast version of the algorithm fro...

We apply the theory of Weyl-Heisenberg frames (WHFs) to oversampled FIR and IIR DFT filter banks (FBs). We show that the polyphase matrices provide a matrix representation of the frame operator, and we find conditions on a DFT FB to provide a WHF expansion. We also show that paraunitary and biorthogonal DFT FBs correspond to tight and exact WHFs, respectively, and that the frame bounds can be o...

This paper presents formulas for the number of optimization parameters (degrees of freedom) when designing Type I linear-phase finite-length impulse response (FIR) Lthband filters of order 2N as cascades of identical linear-phase FIR spectral factors of order N. We deal with two types of degrees of freedom referred to as (i) the total degrees of freedom DT, and (ii) the remaining degrees of fre...

An efficient method for the design of low-delay two-channel, perfect reconstruction IIR filter banks is proposed. The design problem is formulated in terms of minimax designs of a general stable IIR filter that can be obtained using semidefinite programming and an FIR filter that can be obtained using the Remez exchange algorithm. A multiplierless implementation on this filter bank is also prop...

Limited frequency response of impulse voltage dividers contributes to the measurement errors of the peak voltage and time parameters. This paper investigates the convolution method for the determination of the errors of lightning impulse parameters due to non-ideal step responses. The step response of a damped capacitor divider with a voltage rating of 2.2 MV was measured and analytical lightni...

In most approximation techniques for implementing a variable fractional delay, the magnitude response usually varies considerably with the delay. However, it would be desirable to keep the magnitude response the same for all delay values. In this paper, we propose a novel method for optimizing the parameters of the least-squared error spline transition band fractional delay FIR design to achiev...