递推数字滤波器的设计方法

本文综述三种主要的递推数字滤波器:切比晓夫Ⅰ型、切比晓夫Ⅱ型及椭圆滤波器的设计方法,给出具体的设计过程与实现方法,并对这三种滤波器的性能进行比较,以便于工程实际应用.     

基于神经网络的FIR多阻带数字滤波器的设计及应用

针对电子测量系统中的工频50Hz及其二次三次谐波干扰，本文运用BP神经网络设计一个三阻带数字滤波器，利用神经网络权值与FIR数字滤波器脉冲响应之间的关系，得出所设计滤波器的脉冲响应。实验表明，与窗函数法设计的三阻带滤波器相比，基于神经网络的FIR三阻带滤波器具有明显的优越性。     

基于TMS320C 5410EVM 板FIR滤波器算法与设计方法研究

数字滤波器是语言、图象处理、模式识别以及谱分析中的基本运算的处理运算。本文研究DSP中有限冲击响应(FIR)滤波器的原理并结合TM320C5410EVM板介绍FIR滤波器设计方法以及DSP中FIR滤波嚣的实现方法。     

对三角级数的广义Padé有理逼近

§1.引言 有理函数的广义Pade逼近是有效的有理函数逼近方法之一,同时在递归数字滤波器的设计中有着重要应用。本文着重讨论广义Pade逼近的性质及有关的问题。 设实序列d_t(t=0,1,2,…)是平方可和的,即     

紧支小波的构造及应用

冉启文、王建赜．紧支小波的构造及应用．紧支小波在数据压缩、图象处理、奇性分析和数字滤波器设计中经常被使用。本文介绍紧支正交小波的构造方法以及紧支小波的识别数字信号频率畸变中的应用     

用提升方法设计三带自适应双正交滤波器组

自适应滤波器组设计是多速率滤波器组理论和应用的一个重要方面.由于其频率响应更好地匹配于输入信号的统计特性,这类滤波器组可获得更大的子带编码增益.研究了用提升方法设计三带自适应双正交滤波器组,给出了设计算法.最后,给出例子,说明其子带编码增益明显提高.     

不确定离散脉冲系统的鲁棒H∞滤波问题

研究一类离散脉冲不确定系统的鲁棒H∞滤波器设计问题.首先,介绍了脉冲线性滤波器与离散脉冲系统的鲁棒H∞滤波问题.其次,基于离散Liapunov函数方法,给出了用线性矩阵不等式表达的滤波误差系统渐近稳定的充分条件与H∞脉冲线性滤波器的设计方法.最后,给出数值例子说明结果的有效性.     

通带可调相位 FIR 数字滤波器及其设计

常见的 FIR 数字滤波器大致可分为两类:一类是线性相位滤波器;另一类是极小相位滤波器,这两种类型的滤波器,其相位响应均不可调.第一种滤波器,其群延迟为((N-1)T)/2,其中 N 为滤波器长度,T 为采样周期.以 N=60,T=0.2秒的线性相位滤波器为例,它的相位响应为     

驻留概率信息方法的离散切换系统H_∞滤波器设计

通过基于驻留概率信息的方法,研究了一类具有时变延迟离散切换系统的H_∞滤波器设计的问题.通过对切换系统在每个子系统的驻留概率信息加以利用,建立一种新型切换系统模型和滤波器模型.利用Lyapunov函数及线性矩阵不等式方法,给出切换系统的H_∞均方稳定的充分条件,然后得到H_∞滤波器增益.最后,通过仿真算例来验证文章所用方法的有效性.     

一维参数化正交小波滤波器的解析性质与优化逼近

本文给出了一维参数化正交小波滤波器系数向量的解析表达式和它的递推计算公式,还给出了它的一阶变分及二阶变分公式．利用这些结果和最优化方法,给出了FIR正交小波滤波器的逼近和设计问题的优化模型和数值例子．     

A Review of the Theory and Applications of Optimal Subband and Transform Coders

The problem of optimizing digital filter banks based on input statistics was perhaps first addressed nearly four decades ago by Huang and Schultheiss. These authors actually considered a special case, namely transform coder optimization. Many of the subband coder optimization problems considered in recent years have close similarities to this work, though there are fundamental differences as well. Filter banks are used today not only for signal compression, but have found applications in signal denoising and in digital communications. A recent result is that principal component filter banks (PCFBs) offer an optimal solution to many problems under certain theoretical assumptions. While this result is quite powerful and includes several earlier results as special cases, there still remain some open problems in the area of filter bank optimization. We first give a review of the older classical methods to place the ideas in the right perspective. We then review recent results on PCFBs. The generality of these results is demonstrated by showing an application in digital communications (the discrete multitone channel). We show, for example, that the PCFB minimizes transmitted power for a given probability of error and bit rate. Future directions and open problems are discussed as well.     

Strictly passive suppression of limit cycles in direct form digital filters with saturation nonlinearity: linear matrix inequality approach

In this paper, we propose a new linear matrix inequality criterion for suppression of limit cycles in state–space direct form digital filters with saturation arithmetic and external interference via a passivity approach. The passive approach is employed to reduce the effect of external interference on the digital filter. The criterion guarantees not only asymptotic stability but also passivity from the external interference to the output vector. This criterion is in the form of linear matrix inequality; hence, it is computationally tractable. An example shows the effectiveness of the proposed criterion. Copyright © 2013 John Wiley & Sons, Ltd.     

Estimation of IIR Systems with Binary-Valued Observations*

Estimation and control problems with binary-valued observations exist widely in practical systems. However, most of the related works are devoted to finite impulse response (FIR for short) systems, and the theoretical problem of infinite impulse response (IIR for short) systems has been less explored. To study the estimation problems of IIR systems with binary-valued observations, the authors introduce a projected recursive estimation algorithm and analyse its global convergence properties, by using the stochastic Lyapunov function methods and the limit theory on double array martingales. It is shown that the estimation algorithm has similar convergence results as those for FIR systems under a weakest possible non-persistent excitation condition. Moreover, the upper bound for the accumulated regret of adaptive prediction is also established without resorting to any excitation condition.     

Formative Use of Intuitive Analysis of Variance

Students’ informal inferential reasoning (IIR) is often inconsistent with the normative logic underlying formal statistical methods such as Analysis of Variance (ANOVA), even after instruction. In two experiments reported here, student's IIR was assessed using an intuitive ANOVA task at the beginning and end of a statistics course. In both experiments, students were provided feedback regarding the normative logic underlying ANOVA and how their reasoning compared with it. Additionally, students in Experiment 2 were given an assignment in which they analyzed and interpreted other students’ performance on the intuitive ANOVA task. Results indicate that the feedback combined with the assignment (which required active explanation of both normative and non-normative reasoning applied to the task) led to more normative inferential reasoning at the end of the course, whereas providing feedback alone did not. Implications are discussed for using the intuitive ANOVA task as a formative classroom tool to help students improve their conceptual understanding of ANOVA.     

Design of two-dimensional recursive filters

The paper discusses a numerical algorithm for obtaining rational approximations to a given continuous function. This method offers the promise of a comprehensive solution to the problems of two-dimensional recursive digital filter design. This technique, called Chebyshev design, avoids the stability test inherent in present design methods.     

Fast algorithms for designing variable FIR notch filters

The paper presents fast algorithms for designing finite impulse response (FIR) notch filters. The aim is to design a digital FIR notch filter so that the magnitude of the filter has a deep notch at a specified frequency, and as the notch frequency changes, the filter coefficients should be able to track the notch fast in real time. The filter design problem is first converted into a convex optimization problem in the autocorrelation domain. The frequency response of the autocorrelation of the filter impulse response is compared with the desired filter response and the integral square error is minimized with respect to the unknown autocorrelation coefficients. Spectral factorization is used to calculate the coefficients of the filter. In the optimization process, the computational advantage is obtained by exploiting the structure of the Hessian matrix which consists of a Toeplitz plus a Hankel matrix. Two methods have been used for solving the Toeplitz‐plus‐Hankel system of equations. In the first method, the computational time is reduced by using Block–Levinson's recursion for solving the Toeplitz‐plus‐Hankel system of matrices. In the second method, the conjugate gradient method with different preconditioners is used to solve the system. Comparative studies demonstrate the computational advantages of the latter. Both these algorithms have been used to obtain the autocorrelation coefficients of notch filters with different orders. The original filter coefficients are found by spectral factorization and each of these filters have been tested for filtering synthetic as well as real‐life signals. Copyright © 2007 John Wiley & Sons, Ltd.     

Digital stochastic control of distributed-parameter systems

This paper presents a method for discrete-time control and estimation of flexible structures in the presence of actuator and sensor noise. The approach consists of complete decoupling of the modal equations and estimator dynamics based on the independent modal-space control technique and modal spatial filtering of the system output. The solution for the Kalman filter gains reduces to that of independent second-order modal estimators, thus permitting real-time digital control of distributed-parameter systems in a noisy environment. The method can be used to control and estimate any number of modes without computational restraints and is theoretically free of observation spillover. Two examples, the first using nonlinear, quantized control and the second using linear, state feedback control are presented.This work was supported by the National Science Foundation, Grant No. PFR-80-20623.     

The Potential Theory of Several Intervals and Its Applications

Motivated both by digital filter design and polynomial-based matrix iteration methods, we study Green's function for the complement of a union of disjoint closed intervals. The key tool is the Schwarz—Christoffel map. Asymptotic analysis produces simple and useful leading terms for Green's function and the associated equilibrium distribution. Our results are applied to optimal lowpass filters and matrix iterations. Accepted 12 February 2001. Online publication 18 May 2001.