Efficient method for designing two-channel PR FIR filter banks with low system delay

In this paper, an efficient method for designing perfect reconstruction (PR) two-channel finite impulse response (FIR) filter banks with low system delay is proposed. It is based on the use of nonlinear-phase FIR function in a structure previously proposed by Phoong et al. The design problem is formulated as a complex polynomial approximation problem and is solved effectively using the Remez exchange algorithm with very low design complexity. Design examples show that filter banks with flexible stopband attenuation and system delay can be readily obtained by the proposed algorithm.published_or_final_versio

Design and multiplier-less implementation of a class of two-channel PR FIR filterbanks and wavelets with low system delay

In this paper, a new method for designing two-channel PR FIR filterbanks with low system delay is proposed. It is based on the generalization of the structure previously proposed by Phoong et al. Such structurally PR filterbanks are parameterized by two functions (β(z) and α(z)) that can be chosen as linear-phase FIR or allpass functions to construct FIR/IIR filterbanks with good frequency characteristics. The case of using identical β(z) and α(z) was considered by Phoong et al. with the delay parameter M chosen as 2N - 1. In this paper, the more general case of using different nonlinear-phase FIR functions for β(z) and α(z) is studied. As the linear-phase constraint is relaxed, the lengths of β(z) and α(z) are no longer restricted by the delay parameters of the filterbanks. Hence, higher stopband attenuation can still be achieved at low system delay. The design of the proposed low-delay filterbanks is formulated as a complex polynomial approximation problem, which can be solved by the Remez exchange algorithm or analytic formula with very low complexity. In addition, the orders and delay parameters can be estimated from the given filter specifications using a simple empirical formula. Therefore, low-delay two-channel PR filterbanks with flexible stopband attenuation and cutoff frequencies can be designed using existing filter design algorithms. The generalization of the present approach to the design of a class of wavelet bases associated with these low-delay filterbanks and its multiplier-less implementation using the sum of powers-of-two coefficients are also studied.published_or_final_versio

New design and realization techniques for a class of perfect reconstruction two-channel FIR filterbanks and wavelets bases

This paper proposes two new methods for designing a class of two-channel perfect reconstruction (PR) finite impulse response (FIR) filterbanks (FBs) and wavelets with K-regularity of high order and studies its multiplier-less implementation. It is based on the two-channel structural PR FB proposed by Phoong et al. The basic principle is to represent the K-regularity condition as a set of linear equality constraints in the design variables so that the least square and minimax design problems can be solved, respectively, as a quadratic programming problem with linear equality constraints (QPLC) and a semidefinite programming (SDP) problem. We also demonstrate that it is always possible to realize such FBs with sum-of-powers-of-two (SOPOT) coefficients while preserving the regularity constraints using Bernstein polynomials. However, this implementation usually requires long coefficient wordlength and another direct-form implementation, which can realize multiplier-less wavelets with K-regularity condition up to fifth order, is proposed. Several design examples are given to demonstrate the effectiveness of the proposed methods. © 2004 IEEE.published_or_final_versio

Design of two-channel PR FIR filter banks with low system delay

IEEE International Symposium on Circuits and Systems, Geneva, Switzerland, 28-31 May 2000In this paper, a new approach for designing two-channel PR FIR filter banks with low system delay is proposed. It is based on the generalization of the structure previously proposed by Phoong et al. Such structurally PR filter banks are parameterized by two functions α(z) and β(z) which can be chosen as linear-phase FIR or allpass functions to construct FIR/IIR filter banks with good frequency characteristics. In this paper, the more general case of using different nonlinear-phase FIR functions for β(z) and α(z) is studied. As the linear-phase requirement is relaxed, higher stopband attenuation can still be achieved at low system delay. The design of the proposed low-delay filter banks is formulated as a complex polynomial approximation problem, which can be solved by the Remez exchange algorithm or analytic formula with very low complexity. The usefulness of the proposed algorithm is demonstrated by several design examples.published_or_final_versio

Performance Analysis of IIR and FIR Filters for 5G Wireless Networks

This paper analyses the performances of the Infinite Impulse Response (IIR) and Finite Impulse Response (FIR) filters. By studying the relationship between filter responses with filter orders and delay, the goal is to choose feasible filters that can accommodate more carriers in a bandwidth thus, the spectral efficiency can be increased. For IIR filtering, we employ filters namely Butterworth, Chebyshev, and Elliptic, while the Equiripple, Bohman, and Hamming are studied for FIR filtering. We evaluate these filters in terms of magnitude response, phase response and group delay, and identify the minimum filter order that characterized nearly to an ideal filter response. The results show that the IIR filter has a steep transition region when compared to the FIR filters under the similar order.  Our performance analysis showed that the IIR filters, with similar filter order of FIR filters, have also the fastest roll-off, small transition region, and low implementation cost. On the other hand, the FIR filters have linear phase response that related to group delay.  Finally, our analysis concluded that Elliptic able to suppress the sidelobes with a minimum order of 10th   and Equiripple have the fastest roll-off and narrowest transition region compare to other tested FIR filter. Thus, make these two types of filter feasible candidates to be implemented in 5G wireless networks

A robust and scalable implementation of the Parks-McClellan algorithm for designing FIR filters

Preliminary version accepted for publicationInternational audienceWith a long history dating back to the beginning of the 1970s, the Parks-McClellan algorithm is probably the most well-known approach for designing finite impulse response filters. Despite being a standard routine in many signal processing packages, it is possible to find practical design specifications where existing codes fail to work. Our goal is twofold. We first examine and present solutions for the practical difficulties related to weighted minimax polynomial approximation problems on multi-interval domains (i.e., the general setting under which the Parks-McClellan algorithm operates). Using these ideas, we then describe a robust implementation of this algorithm. It routinely outperforms existing minimax filter design routines

A FRAMEWORK FOR OPTIMAL DESIGN OF LOW-POWER FIR FILTERS

Approximate Computing has emerged as a new low-power design approach for application domains characterized by intrinsic error resilience. Digital Signal Processing (DSP) is one such domain where outputs of acceptable quality can be produced even though the internal computations are carried out in an approximate manner. With the ever increasing need for data rates at lower power usage; the need for improved complexity reduction schemes for DSP systems continues. One of the most widely performed steps in DSP is FIR filtering. FIR filters are preferred due to their linea