Design of 1-D Stable Variable Fractional Delay IIR Filters

In this brief, a two-stage approach for the design of 1-D stable variable fractional delay infinite-impulse response (IIR) digital filters is proposed. In the first stage, a set of fixed delay stable IIR filters are designed by minimizing a quadratic objective function, which is defined by integrating error criterion with IIR filter stability constraint condition. Then, the final design is determined by fitting each of the fixed delay filter coefficients as a 1-D polynomial. Two design examples are given to show the effectiveness of the proposed design method     

Design of Constrained Causal Stable IIR Filters Using a New Second- Order-Cone-Programming-Based Model-Reduction Technique

This brief proposes a new method for designing infinite-impulse response (IIR) filter with peak error and prescribed flatness constraints. It is based on the model reduction of a finite-impulse response function that satisfies the specification by extending a method previously proposed by Brandenstein. The proposed model-reduction method retains the denominator of the conventional techniques and formulates the optimal design of the numerator as a second-order cone programming problem. Therefore, linear and convex quadratic inequalities such as peak error constraints and prescribed number of zeros at the stopband for IIR filters can be imposed and solved optimally. Moreover, a method is proposed to express the denominator of the model-reduced IIR filter as a polynomial in integer power of z, which efficiently facilitates its polyphase implementation in multirate applications. Design examples show that the proposed method gives better performance, and more flexibility in incorporating a wide variety of constraints than conventional methods     

Generalized Chebyshev Filters for the Design of IIR Filters and Filter Banks

This paper introduces the generalized IIR Chebyshev filters. The proposed filters are obtained by applying bilinear transformation to the corresponding analog filters. The novelty of the method is the introduction of a new rational Chebyshev function, which includes Chebyshev Type I and Chebyshev Type II IIR filters as special cases. The application of the proposed digital filters to design perfect reconstruction two-channel filter banks is described. The proposed filters can be applied in orthogonal discrete wavelet transform.     

基于DSP Builder和FPGA的IIR滤波器设计

针对传统的基于现场可编程门阵列（FPGA）的数字滤波器设计所需周期长,提出了基于dsp builder和FPGA的滤波器设计,完全实现自顶向下的设计流程。在此基础上设计实现四节级联IIR,并结合MATLAB强大计算功能,提出了利用MATLAB和Quartus II联合仿真算法;使输出复杂的数据变为波形,易于观察仿真结果,增强了Quartus的仿真功能。结果表明设计的IIR滤波器完全达到设计要求。     

IIR数字滤波器设计的粒子群优化算法

本文探讨了粒子群优化算法及其性能评估准则，然后重点研究了IIR数字滤波器设计的粒子群优化算法及其实现步骤。最后，通过IIR数字低通、带通滤波器设计两个实例证明了本文算法的有效性。     

A New Method for Designing Causal Stable IIR Variable Fractional Delay Digital Filters

This paper studies the design of causal stable Farrow-based infinite-impulse response (IIR) variable fractional delay digital filters (VFDDFs), whose subfilters have a common denominator. This structure has the advantages of reduced implementation complexity and avoiding undesirable transient response when tuning the spectral parameter in the Farrow structure. The design of such IIR VFDDFs is based on a new model reduction technique which is able to incorporate prescribed flatness and peak error constraints to the IIR VFDDF under the second order cone programming framework. Design example is given to demonstrate the effectiveness of the proposed approach.     

Minimax Design of IIR Digital Filters Using SDP Relaxation Technique

This paper presents a new algorithm using semidefinite programming (SDP) relaxation to design infinite impulse response digital filters in the minimax sense. Unlike traditional design algorithms that try to directly minimize the error limit, the proposed algorithm employs a bisection searching procedure to locate the minimum error limit of the approximation error. Given a fixed error limit at each iteration, the SDP relaxation technique is adopted to formulate the design problem in a convex form. In practice, the true minimax design cannot be always obtained. Thus, a regularized feasibility problem is adopted in the bisection searching procedure. The stability of the designed filters can also be guaranteed by adjusting the regularization coefficient. Unlike other sequential design methods, the proposed algorithm tries to find a feasible solution at each iteration of the sequential design procedure within a feasible set defined by the relaxed constraints. This feasible set is not restricted within the neighborhood of a given point obtained from the previous iteration. Thus, the proposed method can avoid being trapped in the locally minimum point. Four examples are presented in this paper to demonstrate the effectiveness of the proposed method.      

用双线性变换法设计IIR滤波器

给出了用双线性变换法设计IIR数字滤波器的方法,并通过用MATLAB语言来实现。双线性法可以使系统经变换后仍保持原有特性,而且这种方法是S域和Z域的单值一一对应,克服了频率交叠产生的混叠效应;最后使用MATLAB语言实现了满足要求的低通IIR滤波器,从而证明了椭圆滤波器具有最优特性。     

基于Matlab的IIR数字滤波器设计方法比较及应用

滤波是信号处理的基础,滤波运算是信号处理中的基本运算,滤波器的设计也就相应成为数字信号处理的最基本问题之一。这里着重IIR数字滤波器的设计研究,应用Butterworth滤波器,ChebysheveⅠ型滤波器,ChebysheveⅡ型滤波器以及椭圆滤波器分别对低通、高通、带通和带阻四种滤波器形式进行比较仿真,通过不同设计方法的对比,将各种滤波器的设计特点很好地呈现出来。应用了Butterworth滤波器实现了混合信号频谱的分离,取得了良好的仿真效果。     

基于巴特沃斯逼近的二维IIR数字滤波器的设计

本文给出了一种基于巴特沃斯逼近的二维ＩＩＲ数字滤波器的设计方法，得到了由基本的全通节级联，并联实现的各种二维滤波器函数，包括，镜象对称互补滤波器，扇形滤波器和具有任意矩形通、阻带的滤波器，结果表明，这种实现结构具有通有灵敏度低、滤波器系数少的优点，并且由于巴特沃斯逼近的最大平坦性，得到的滤波器具有良好的相位特性。     

线性相位IIR滤波器的逼近

基于内平衡结构模型压缩法，通过对线性相位FIR滤波器的降阶处理，本文得到了一种稳定的线性相位IIR滤波器的逼近方法，计算机模拟结果证实了本文的理论分析．     

Design and Factorization of Two-Channel Perfect Reconstruction Filter Banks with Causal-Stable IIR Filters

In this paper, new design and factorization methods of two-channel perfect reconstruction (PR) filter banks (FBs) with casual-stable IIR filters are introduced. The polyphase components of the analysis filters are assumed to have an identical denominator in order to simplify the PR condition. A modified model reduction is employed to derive a nearly PR causal-stable IIR FB as the initial guess to obtain a PR IIR FB from a PR FIR FB. To obtain high quality PR FIR FBs for carrying out model reduction, cosine-rolloff FIR filters are used as the initial guess to a nonlinear optimization software for solving to the PR solution. A factorization based on the lifting scheme is proposed to convert the IIR FB so obtained to a structurally PR system. The arithmetic complexity of this FB, after factorization, can be reduced asymptotically by a factor of two. Multiplier-less IIR FB can be obtained by replacing the lifting coefficients with the canonical signal digitals (CSD) or sum of powers of two (SOPOT) coefficients.     

Design of Robust D-Stable IIR Filters Using Genetic Algorithms With Embedded Stability Criterion

This paper proposes a novel evolution strategy for a genetic algorithm (GA). This new algorithm is then applied to design robust D(alpha,r)-stable infinite-impulse-response (IIR) filters. Unlike existing research on designing IIR filters by using GA, in which the stability of IIR filters is tested by trial and error after the evolution of each generation of a GA, the stability criterion in this paper is embedded within the evolution of each generation. Consequently, the stability of this system can be guaranteed without the need for any other checks of the stability criterion in the evolution of each generation. Numerical experimental results are discussed to illustrate the soundness of the proposed evolution strategy. The robustness of the IIR filters is achieved by ensuring that all poles of the filters are located inside a disk D(alpha,r) contained in the unit circle, in which alpha is the center, r is the radius of the disk and IalphaI +r < 1 . So, in this paper, a D(alpha,r)-stability criterion will be first derived and then embedded in the GA for the design of robust IIR filters. Finally, two examples will be presented to show that the designed filters remain D(alpha,r)-stable during the evolution of the GA and will provide satisfactory results.     

Factorized All-Pass Based IIR Adaptive Notch Filters

This paper introduces a new family of infinite impulse response adaptive notch filters that forms multiple notches using a second-order factorization of an all-pass transfer function. The new orthogonal realization is amenable for adaptive filtering to obtain the unknown frequencies of interest. Two new adaptive filtering algorithms are presented that can achieve fast convergence at low computational cost. Local convergence analysis for the new algorithms is performed, and a detailed discussion of their properties is provided. The new all-pass based notch realization introduces a different compromise between bias and signal-to-noise ratio (SNR) when compared with realizations previously reported in the literature. Specifically, it achieves lower bias than other approaches at low SNR. This property is particularly attractive for the estimation and tracking of multiple sinusoids. Furthermore, the bias can be made arbitrarily small or can be accurately estimated and compensated for. Extensive computer simulations are provided to illustrate the performance of the proposed adaptive notch filters in terms of bias, speed of convergence, and tracking capability.     

可用于DSSS系统时变干扰抑制的IIR滤波器设计

在理想的干扰瞬时频率估计条件下,推导Kwan-Martin结构IIR干扰抑制滤波器相关输出信干噪比改善因子的闭合表达式。与五系数时变FIR滤波器干扰抑制性能比较表明,IIR滤波器对DSSS信号的失真远小于FIR滤波器,信干噪比改善因子与干扰瞬时频率及系统扩展比无关,干扰抑制性能优于时变FIR滤波结构。     

设计IIR数字滤波器的遗传优化算法

提出了ＩＩＲ数字滤波器设计的遗传优化法。这是一种模拟自然遗传和达尔文进化理论的随机并行优化算法。首先，详细描述了遗传算法并给出了计算步骤，然后将遗传算法用于ＩＩＲ数字滤波器的优化设计，最后给出了模拟计算结果。     

一种新型低复杂度的IIR格型滤波器

格型结构具有良好的抗有限字长效应能力而被应用于很多实时性较高的场合.归一化格型结构具备正交的特性,然而,对于一个N阶数字滤波器,它需要5N+1个乘法器.为了降低其实现复杂度,并保留正交的特性,本文基于单,双,三乘法器格型单元导出了其对应的新型格型单元和格型结构.仿真结果表明,当采用单乘法器新型格型单元时,新结构抵抗有限字长误差的能力与归一化格型结构非常接近,但由于其只需2N+1个乘法器,新结构在实时信号处理中具有更大的实用价值.