离散时间系统Hankel最优模型降阶及其应用

针对离散时间系统Hankel最优模型降阶问题,对标量情况由最优Hankel范数近似给出了状态空间解。将这一理论应用于无限脉冲响应（IIR）滤波器的设计,进一步提出了一种基于最优Hankel范数近似的线性相位IIR滤波器设计方法。通过采用线性相位FIR滤波器和最优Hankel范数近似方法设计IIR滤波器,使其具有线性相位,减小了逆矩阵求解中的计算量。低通滤波器的仿真实例验证了该方法的有效性。     

基于最优Hankel范数近似的线性相位IIR滤波器设计

提出了一类基于最优Hankel范数近似的线性相位无限脉冲响应(IIR)滤波器设计方法.首先给出了Hankel范数的相关预备知识,~然后给出了离散时间单输入单数出系统Hankel范数近似的定理及证明,最后给出了线性相位IIR滤波器的设计步骤.该方法不但减小了逆矩阵求解过程中的计算量,~同时给出了L_∞范数近似的误差边界.仿真结果验证了该方法的有效性.     

一种设计IIR QMF滤波器组的新方法

本文提出了一种新的设计两通道近似完全重构IIR滤波器组的方法.分析滤波器组由基于全通滤波器的多相网络实现,所引起的相位失真几乎完全被综合滤波器组所平衡.从QMF的完全重构理论出发,提出综合滤渡器组也由全通滤波器来实现,整个系统的设计就转化成相位均衡器的设计,并且给出构成综合滤波器组的稳定的全通滤波器的封闭解析表达式,仿真结果证明,该方法设计的系统不仅完全消除了幅度和混叠失真,相位失真可以在附加一定的信号延时的基础上进行最小化,而且计算量小,系统恒稳定.     

具有良好重建特性的正交镜像IIR滤波器组的设计新方法

提出了一种新的设计两通道近似完全重构IIR滤波器组的方法.分析滤波器组由基于全通滤波器的多相网络实现,所引起的相位失真几乎完全被综合滤波器组所平衡.从QMF的完全重构理论出发,提出综合滤波器组也由全通滤波器来实现,整个系统的设计就转化成相位均衡器的设计,并且给出构成综合滤波器组的稳定的全通滤波器的封闭解析表达式.仿真结果证明,本方法设计的系统不仅完全消除了幅度和混叠失真,相位失真可以在附加一定的信号延时的基础上进行最小化,而且计算量小,系统恒稳定.     

相位噪声模拟器实现技术研究

研究Ka频段通信卫星系统信道相位噪声模拟方法与硬件实现技术。提出在中频采用多级IIR滤波器并联的形式产生幂律分布噪声,用于实现相位噪声特性模拟的方法。给出IIR滤波器组的设计方法以及相位噪声的模拟精度,并基于FPGA+DSP硬件平台实现了相位噪声模拟器,实测曲线表明其模拟范围优于Aeroflex信道模拟器。     

基于FPGA的ⅡR滤波器整数设计

提出了一种在FPGA中以整数方式实现IIR滤波器的方法，讨论了取整舍入误差对IIR滤波器的稳定性影响．针对df2形式及FPGA迭代运算提出以变量T的传函增益限定输入信号范围的方法，使得IIR滤波器在FPGA中稳定运行；最后给出编程方法。通过实验验证，该方法设计的IIR滤波器收敛，具有广泛的工程应用。     

基于MATLAB的约束最小二乘法FIR数字滤波器设计

在数字信号处理领域中,无限脉冲响应数字滤波器(IIR)和有限脉冲响应数字滤波器(FIR)占有极其重要的地位。但是,IIR数字滤波器存在诸如稳定性难以保障以及相位的非线性等一些固有缺点,这使得具有线性相位等优点的FIR数字滤波器得到很好的发展。本文介绍基于MATLAB的约束最小二乘法FIR数字滤波器设计。包括约束最小二乘法基本原理和FIR数字滤波器设计思想以及相关MATLAB程序语言,并介绍MATLAB的SPTooL滤波器设计器及其应用。     

基于MATLAB的约束最小二乘法FIR数字滤波器设计

在数字信号处理领域中,无限脉冲响应数字滤波器（IIR）和有限脉冲响应数字滤波器（FIR）占有极其重要的地位。但是,IIR数字滤波器存在诸如稳定性难以保障以及相位的非线性等一些固有缺点,这使得具有线性相位等优点的FIR数字滤波器得到很好的发展。本文介绍基于MATLAB的约束最小二乘法FIR数字滤波器设计。包括约束最小二乘法基本原理和FIR数字滤波器设计思想以及相关MATLAB程序语言,并介绍MATLAB的SPTooL滤波器设计器及其应用。     

汽车超载检测仪的IIR滤波器设计及仿真

数字滤波技术是数字信号处理的一个重要组成部分,数字滤波器的设计是汽车超载快速检测仪中数字信号处理的核心部分.本文根据IIR滤波器的设计原理,提出了基于MATLAB环境下汽车超载快速检测仪的IIR滤波器设计方法.文中给出了IIR滤波器设计实例,仿真结果表明设计的各项性能指标均达到了该检测仪的指定要求.     

线性相位NPR DFT滤波器组设计

提出了一种具有不同分析和综合原型滤波器的线性相位过采样NPR DFT调制滤波器组的设计方法。根据滤波器组在子带混叠、系统输出混叠、系统失真三方面的要求,推导并给出了相应的设计算法。不同的分析、综合原型滤波器的使用增加了设计自由度,可以有效改善滤波器组的整体性能。另外,由于考虑了线性相位约束,滤波器组的通带平坦性约束变得更为简单,简化了设计算法。     

Properties,implementations and applications of rank filters

The results of research on rank filters are presented. The relationship of rank filters with other filters is briefly discussed. The main properties of rank filters are listed and an explanation is given for these properties. Several software and hardware implementations of the filter are described. Major applications to image processing are discussed, including noise smoothing, cluster detection, skeletization, edge enhancement and edge detection.     

A Note on Two Classical Enhancement Filters and Their Associated PDE's

We establish in 2D, the P.D.E. associated with a classical image enhancement filter, the Kramer operator and compare it with another classical shock filter, the Osher-Rudin filter. We show that each one corresponds to a non-flat mathematical morphology operator conditioned by a the sign of an edge detector. In the case of the Kramer operator, the equation is conditioned by the Canny edge detector while in the case of the original Rudin-Osher filter, the equation is conditioned by the sign of the Laplacian.     

Range filters: Localintensity subrange filters and their properties

A local filter which uses the local-intensity subrange of pixel intensity values within a window is described. The range filter is an extension of the rank filter and has been found useful for detecting edges. The deterministic and noise properties of the range filter are described and compared with those of the commonly used Sobel filter.     

一种改进的n维空间递归滤波算法

基于递归运算准则,本文提出了一种n维空间非线性滤波器的改进算法。该算法利用像素点的周边信息完成对噪声点的识别与修复。此n维空间滤波器可以递归地分解到更低一维空间,本文主要分析了这种改进的滤波算法在二维空间信号消噪处理中的性能。仿真结果表明,与中值滤波和Peak-and-Valley滤波算法比较,该算法在信噪比和图像细节保留方面具有更大的优势,并且在有高强度的脉冲噪声时也能达到较为理想的滤波效果。     

Improving Deriche-style Recursive Gaussian Filters

Gaussian smoothing filters and Gaussian derivative filters can be estimated by recursive IIR filters, as shown by Deriche [3, 4]. The design of those filters does, however, not enforce the important property that derivative filters should have an exactly zero DC-response. This article extends the theory in [4] to take this constraint into account without loss of performance and also gives new compact closed form expressions for the normalization factors required for proper scaling of the filter responses.     

Adaptive correlation filters for pattern recognition

Adaptive correlation filters based on synthetic discriminant functions (SDFs) for reliable pattern recognition are proposed. A given value of discrimination capability can be achieved by adapting a SDF filter to the input scene. This can be done by iterative training. Computer simulation results obtained with the proposed filters are compared with those of various correlation filters in terms of recognition performance. The text was submitted by the authors in English. Vitaly Kober obtained his MS degree in Applied Mathematics from the Air-Space University of Samara (Russia) in 1984 and his PhD degree in 1992 and Doctor of Sciences degree in 2004 in Image Processing from the Institute of Information Transmission Problems, Russian Academy of Sciences. He is now a titular researcher at the Centro de Investigatión Cientifica y de Educatión Superior de Ensenada (Cicese), Mexico. His research interests include signal and image processing and pattern recognition. Mikhail Mozerov received his MS degree in Physics from Moscow State University in 1982 and his PhD degree in Image Processing from the Institute of Information Transmission Problems, Russian Academy of Sciences, in 1995. He is with the Laboratory of Digital Optics of the Institute of Information Transmission Problems, Russian Academy of Sciences. His research interests include signal and image processing, pattern recognition, and digital holography. Iosif A. Ovseyevich graduated from the Moscow Electrotechnical Institute of Telecommunications. He received his candidate’s degree in 1953 and doctoral degree in Information Theory in 1972. At present he is Emeritus Professor at the Institute of Information Transmission Problems, Russian Academy of Sciences. His research interests include information theory, signal processing, and expert systems. He is a Member of the IEEE and Popov Radio Society.     

采用8031作主控器的时域FIR数字滤波器

长期以来，ＦＩＲ数字滤波器大多是在频域上实现。因为，在时域上实现ＦＩＲ数字滤波所遇到的首要问题，是输入信号序列与冲激响应序列的卷积运算速度难以提高。然而，随着超大规模集成电路的飞速发展，硬件集成度与运算速度获得极大的改观，在时域上实现ＦＩＲ数字滤波已成为可能。ＩＭＳＡ１００是高速、高精度３２级数字信号处理器，是完成卷积运算的理想器件。本文论证了用ＩＭＳＡ１００实现时域ＦＩＲ数字滤波器的可行性和硬件设计中的一些问题，并给出了应用举例。在设计中选用８０３１单片机做主控器，大大提高了性能价格比，使这一设计具有很高的实用价值。     

多级Volterra滤波器的非线性系统建模

提出多级Ｖｏｌｔｅｒｒａ滤波器非线性建模方法,该滤波器等价于文献「１」给出的分块解耦Ｖｏｌｔｅｒｒａ滤波器,此方法简化了文献「１」中复杂的推导过程,通过比较两种滤波 均方误差,进上步分析其与标准Ｖｏｌｔｅｒｔｒａ滤波器的性能差异,给出了刻画该性能差异的误差量。     

Quintuple-mode wideband bandpass filter based on stub-loaded circular resonator

In this paper, novel compact wideband filters have been implemented using a stub-loaded microstrip resonator based on a circular open-loop configuration for the first time. To offer an alternative wideband filter configuration, the quadruple?/quintuple-mode wideband bandpass filters (BPFs) using stub-loaded circular microstrip resonator (SLCMR) and parallel-coupled microstrip line (PCML) feed configuration are proposed. They are realized by employing a single open stub and two open stubs, respectively. A half-wavelength $\left(\lambda /2\right)$ circular microstrip resonator (CMR) loaded with two open stubs excites three resonant modes, while the one with a single stub produces two resonant modes. One of the modes is odd-mode generated by a $\lambda /2$ CMR, the others are even-modes excited by the two loading stubs. The PCML with enhanced input/output (I/O) coupling degree excites also two modes in the passband. Two loading stubs not only creates transmission poles in the passband, they also create two transmission zeros in the lower and upper stopbands. The quadruple?/quintuple-mode wideband BPFs with fractional bandwidths FBW of 60% and 62% are successfully realized by using the SLCMR and PCML feed configuration together. Both filters are designed, fabricated, and tested where excellent agreement between simulated and measured results is observed.     

Design of coplanar waveguide elliptic low pass filters

This article proposes three design topologies of coplanar waveguide elliptic low pass filters. The design procedure is simple and explained in detail for the first topology. Numerical results are provided using the commercially available simulation softwares IE3D and HFSS to show the validity of the design with very good agreement. The proposed filters yield less than 0.1 dB attenuation in the passband (0–2 GHz), with a controllable slope of the transition between passband and stopband. The width of the rejection band is increased by simple filter cascading resulting in a passband to stopband ratio of up to 1:6. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009.