基于FIR与相位补偿IIR滤波器的雷达回波信号处理

FIR与IIR频率选择滤波器的设计,被广泛应用于数字信号处理领域之中。文章以雷达回波信号的数字处理为例,首先分别设计FIR,IIR滤波器完成了对信号特定频率分量的滤除。进而,针对IIR滤波器的非线性相位,基于最优化设计全通系统实现了相位补偿,并对FIR,IIR滤波器进行了综合比较。     

基于MATLAB的数字滤波器交互界面设计

数字滤波器在数字信号处理中具有举足轻重的作用。在分析IIR数字滤波器和FIR数字滤波器设计原理的基础上,在设计过程中使用MATLAB提供的GUI工具,实现了方便用户使用的数字滤波器交互界面开发,进行应用演示,最后对IIR数字滤波器和FIR数字滤波器进行了对比分析。     

基于System View的FIR数字滤波器设计

探讨了运用SystemView软件,从图形化的工具和数字化的指标入手,抛开传统滤波器设计中繁琐的计算与变换,直接快速实现在数字存储示波器中,为了消除前端系统本身的噪声而设计的FIR数字滤波器。并且运用SystemView软件的分析工具,对所设计的FIR数字滤波器的幅频特性、相频特性、阻带衰减、通带纹波等性能进行了分析。通过分析报表和特性图形显示所设计的FIR数字滤波器技术指标完全满足数字存储示波器系统的技术要求。     

DSSS系统中基于WHT的自适应干扰抑制

本文提出了一种新的DSSS系统自适应干扰抑制方案。针对Wigner-Ville分布的不足,采用WHT来分析接收信号,并从中提取干扰瞬时频率以设计时变IIR滤波器。和通常采用的线性相位FIR滤波器相比,IIR滤波器具有理想的点阻特性。仿真结果证实IIR滤波器的BER性能好于FIR滤波器。     

基于无限冲激响应的微波光子级联滤波器

为进一步拓展微波光子滤波器的 FSR(自由谱范围)和提高滤波器的Q值,进行了 IIR(无限冲激响应)滤波器分别与FIR(有限冲激响应)滤波器和 IIR滤波器级联的研究。分析了两种级联结构的滤波特性并给出了相应的传输函数。IIR滤波器与FIR滤波器级联后的FSR与Q值是IIR滤波器的2n倍;IIR滤波器与IIR滤波器级联后的FSR是各个IIR滤波器的FSR的最小公倍数。用 Matlab软件仿真验证了两种级联结构的频率响应特性,实验验证了 IIR滤波器与 IIR滤波器的级联特性。IIR滤波器与 IIR滤波器的级联有望实现宽频率范围内的单通带滤波器。     

IIR数字滤波器的仿真实现研究

作为改变信号频谱的算法装置,数字滤波器及其设计受到人们广泛地关注,其分为有限长冲激响应（FIR）数字滤波器和无限长冲激响应（IIR）数字滤波器。文中探究具有无限持续时间的冲击响应的IIR数字滤波器系统,并提出如何利用MATLAB软件实现仿真设计。     

基于CORDIC算法的数字滤波器设计

FIR和IIR数字滤波器广泛应用于各种数字信号处理系统。从坐标旋转公式出发，阐述了CORDIC算法的原理．同时在FPGA上实现了该算法的设计，并且基于CORDIC算法建立了FIR和IIR数字滤波器的电路模型，使之能在同一电路上通过开关控制集成实现。     

LMS自适应算法设计FIR,IIR数字滤波器的应用及比较

简要介绍了FIR，IIR数字滤波器的特点，在此基础上应用基于自适应模型的LMS算法对FIR，IIR数字滤波器进行了系数综合，并通过Matlab 6．5计算机仿真比较了不同抽头数时，两种类型滤波器效果的差别，给出了一些重要结论。从计算机仿真结果可以看出，当滤波器抽头数相同时，IIR滤波器具有更好的通带和阻带特性。而随着抽头数目的增加，FIR滤波器的性能可以得到很大改善。当抽头数目足够大时，两种滤波器性能趋于一致。值得指出的是，LMS算法用于FIR滤波器的计算量明显小于相同抽头数的IIR滤波器，因而收敛较快。     

基于SystemView的FIR数字滤波器设计

SystemView是一个信号级的系统仿真软件,主要用于电路与通信系统的设计和仿真,能满足从数字信号处理、滤波器设计,直到复杂的通信系统等不同层次的设计与仿真要求。本文探讨了运用SystemView进行FIR数字滤波器的设计方法,并给出一个典型实例。通过仿真表明,设计结果能够达到指标要求,且设计过程简单易行,具有实用价值。     

基于FPGA的IIR数字滤波器的实现

数字信号处理在科学和工程技术许多领域中得到广泛的应用,与FIR数字滤波器相比,IIR数字滤波器可以用较低的阶数获得较高的选择性,本文采用一种基于FPGA的IIR数字滤波器的设计方案,首先分析了IIR数字滤波器的原理及设计方法,然后通过MAX＋PLUSⅡ的设计平台,采用自顶向下的模块化设计思想将整个IIR数字滤波器分为：时序控制、延时、补码乘加和累加4个功能模块。分别对各模块采用VHDL进行描述后,进行了仿真和综合。仿真结果表明,本课题所设计的IIR数字滤波器运算速度较快,系数改变灵活,有较好的参考价值。     

Frequency domain synthesis of IIR digital filters by means of associated FIR filters

This correspondence describes a synthesis technique for IIR digital filters which allows the use of approximation methods already developed for designing FIR filters. The technique is based on the definition, by means of a suitable transformation, of a FIR filter associated to the desired IIR filter. An example of application is given and the related results are briefly discussed.     

Low-Order IIR Filter Bank Design

The advantage of infinite-impulse response (IIR) filters over finite-impulse response (FIR) ones is that the former require a much lower order (much fewer multipliers and adders) to obtain the desired response specifications. However, in contrast with well-developed FIR filter bank design theory, there is no satisfactory methodology for IIR filter bank design. The well-known IIR filters are mostly derived by rather heuristic techniques, which work in only narrow design classes. The existing deterministic techniques usually lead to too high order IIR filters and thus cannot be practically used. In this paper, we propose a new method to solve the low-order IIR filter bank design, which is based on tractable linear-matrix inequality (LMI) optimization. Our focus is the quadrature mirror filter bank design, although other IIR filter related problems can be treated and solved in a similar way. The viability of our theoretical development is confirmed by extensive simulation.     

Generalized digital Butterworth filter design

This correspondence introduces a new class of infinite impulse response (IIR) digital filters that unifies the classical digital Butterworth filter and the well-known maximally flat FIR filter. New closed-form expressions are provided, and a straightforward design technique is described. The new IIR digital filters have more zeros than poles (away from the origin), and their (monotonic) square magnitude frequency responses are maximally flat at ω=0 and at ω=π. Another result of the correspondence is that for a specified cutoff frequency and a specified number of zeros, there is only one valid way in which to split the zeros between z=-1 and the passband. This technique also permits continuous variation of the cutoff frequency. IIR filters having more zeros than poles are of interest because often, to obtain a good tradeoff between performance and implementation complexity, just a few poles are best     

Digital integrator design using Simpson rule and fractional delay filter

The IIR digital integrator is designed by using the Simpson integration rule and fractional delay filter. To improve the design accuracy of a conventional Simpson IIR integrator at high frequency, the sampling interval is reduced from T to 0.5T. As a result, a fractional delay filter needed to be designed in the proposed Simpson integrator. However, this problem can be solved easily by applying well-documented design techniques of the FIR and all-pass fractional delay filters. Several design examples are illustrated to demonstrate the effectiveness of the proposed method.     

基于树莓派和Python的数字均衡器实验设计

传统的实时性数字音效处理系统主要基于DSP硬件平台进行开发，对于本科生而言开发难度和成本都较高，针对此问题，提出了基于树莓派和Python的数字均衡器综合实验设计方案。首先，提出了一种基于尖峰滤波器模型的均衡器方法；其次，从理论角度阐述了IIR数字滤波器形式的设计过程，并通过窗函数法转换为FIR数字滤波器；最后，借助树莓派数字音效处理系统，印证了实验方案的可行性和拓展性，提高了学生的理论应用能力和创新实践兴趣。     

FIR, Allpass, and IIR Variable Fractional Delay Digital Filter Design

This paper presents two-step design methodologies and performance analyses of finite-impulse response (FIR), allpass, and infinite-impulse response (IIR) variable fractional delay (VFD) digital filters. In the first step, a set of fractional delay (FD) filters are designed. In the second step, these FD filter coefficients are approximated by polynomial functions of FD. The FIR FD filter design problem is formulated in the peak-constrained weighted least-squares (PCWLS) sense and solved by the projected least-squares (PLS) algorithm. For the allpass and IIR FD filters, the design problem is nonconvex and a global solution is difficult to obtain. The allpass FD filters are directly designed as a linearly constrained quadratic programming problem and solved using the PLS algorithm. For IIR FD filters, the fixed denominator is obtained by model reduction of a time-domain average FIR filter. The remaining numerators of the IIR FD filters are designed by solving linear equations derived from the orthogonality principle. Analyses on the relative performances indicate that the IIR VFD filter with a low-order fixed denominator offers a combination of the following desirable properties including small number of denominator coefficients, lowest group delay, easily achievable stable design, avoidance of transients due to nonvariable denominator coefficients, and good overall magnitude and group delay performances especially for high passband cutoff frequency ( ges 0.9pi) . Filter examples covering three adjacent ranges of wideband cutoff frequencies [0.95, 0.925, 0.9], [0.875, 0.85, 0.825], and [0.8, 0.775, 0.75] are given to illustrate the design methodologies and the relative performances of the proposed methods.