There are two types of digital filters including Infinite Impulse Response (IIR) and Finite Impulse Response (FIR). IIR filters attract more attention as they can decrease the filter order significantly compared to FIR filters. Owing to multi-modal error surface, simple powerful optimization techniques should be utilized in designing IIR digital filters to avoid local minimum. Imperialist compe...

Half-band (HB) filters are of great importance and are often used in multirate digital signal processing systems, filter banks and wavelets. In this paper, a new closed-form expression for the transfer function of the maximally flat (MF) infinite-impulse response (IIR) HB filters is presented. The filter coefficients are directly obtained by solving a linear system of Vandermonde equations that...

This paper presents the swarm intelligence (SI)-based particle swarm optimisation (PSO) in context of designing infinite-impulse response (IIR) digital filters. IIR filters are the part of digital filters with recursive responses. Since the error surface of IIR digital filters is generally non-linear and multimodal, global optimisation techniques are required in order to avoid local minima. The...

Fractional delay (FD) filters are an important class of digital filters and are useful in various signal processing applications. In this paper, the design problem of the maxflat FD IIR filters is discussed, and a new closed-form expression for its filter coefficients is presented. The filter coefficients are directly derived by solving a linear system of Vandermonde equations, which are obtain...

In the design of IIR digital filters, the method that utilizes the classic analog filter design theory to design analog filters and then obtain the corresponding digital filters by s–z transformation is well-known. However, IIR digital filters obtained via the bilinear s–z transformation have just equal-order numerator and denominator. Having unequal-order numerator and denominator will give mo...

Abstract—We present a subband adaptive infinite-impulse response (IIR) filtering method, which is based on a polyphase decomposition of IIR filter. Motivated by the fact that the polyphase structure has benefits in terms of convergence rate and stability, we introduce the polyphase decomposition to subband IIR filtering, i.e., in each subband high order IIR filter is decomposed into polyphase I...

Generally Digital Signal Processing is Mathematical manipulation of the signals. The manipulation parameters may get differ from one technique to another. In this paper IIR Butterworth filters has been designed for various orders to analyze group delay. The developed IIR filters are designed and simulated using matlab with different filter orders. The simulated results shows that IIR filters wi...

The transfer function of IIR all-pass filters is a rational function of ω. However, the optimization of such a rational function using the successive projections method, which has a wider range of application than the Remez algorithm, has not been presented. In this paper, we propose designing IIR allpass filters using the successive projections method. key words: successive projections method,...

HRTFs (head-related transfer functions) are available for sound field reproduction with spatial fidelity, since HRTFs involve the acoustic cues such as interaural time difference, interaural intensity difference and spectral cues that are used for the perception of the location of a sound image. Generally, FIR filters are used in the simulation of HRTFs. However, this method is not useful for a...