基于结构进化的无限冲激响应数字滤波器设计方法

针对传统无限脉冲响应(IIR)数字滤波器设计方法存在传输函数在整个设计阶段可能不是最优的问题,提出一种基于遗传算法结构进化的IIR数字滤波器生成方法.该方法直接设计滤波器结构,无需设计传输函数.首先,随机建立一组滤波器结构生成指令序列(SGIS).这些指令序列不仅能控制滤波器结构,也能表示滤波器结构.然后,对这些指令序列进行编码,将它们看作染色体; 最后用遗传算法优化这些染色体,得到最优滤波器.理论分析和实验仿真表明,与传统基于遗传算法系数进化的IIR滤波器方法相比,基于遗传算法结构进化的IIR滤波器通带波纹缩小40.58%,过渡带宽度缩小87.62%,阻带最小衰减减少9.22%.     

基于自由搜索算法的IIR数字滤波器设计

无限脉冲响应(IIR)数字滤波器的设计实质上是一个多参数多目标优化问题。针对自由搜索算法原型优化设计时存在后期寻优效率低等缺陷,提出一种改进搜索策略的优化方法。通过动态调整个体的领域搜索半径和定期轴向搜索等策略,提高算法在多维空间的搜索能力。将其应用于IIR数字滤波器的优化设计,并在最小均方误差、最小通带阻带纹波幅值和两者相结合的优化准则下,对参数空间施加适当的约束条件,建立相应的优化模型。仿真结果表明,在设计IIR数字滤波器时,该算法的优化结果优于同类算法。     

模拟跨导滤波器多目标并行进化的设计

以往模拟滤波器的设计,需要经过人工多次修改、计算和调试。提出一种模拟跨导滤波器的硬件进化结构及多目标并行进化的设计方法。应用一种基于渗透原理迁移策略的多目标并行遗传算法,实现跨导滤波器的参数优化。对多目标并行遗传算法的遗传操作进行了改进,构造了适合滤波器参数进化的多目标适应度函数。在高[Q]值的跨导滤波器的设计中,采用级联法构成的四阶带通跨导滤波器能够满足其在阻带、通带以及过渡带方面的性能要求,对其实效性进行了仿真和验证,进化的参数数值与理论结果符合得非常好。     

基于混沌粒子群优化算法的FIR数字滤波器设计

有限脉冲响应(FIR)数字滤波器的设计,实质上是一个多参数优化问题.将粒子群优化算法与混沌相结合来设计FIR数字滤波器,并用该方法设计了一个高通滤波器.与用Parks-McClellan算法设计得到的高通滤波器进行对比发现,基于混沌粒子群优化算法(CPSO)的FIR滤波器通带波动小,阻带衰减大,从而证明了该算法的有效性和优越性.     

模拟进化型状态变量滤波器的设计

以往的滤波器一旦结构固定后是不能改变其自身参数的,而进化型模拟状态变量滤波器能够随着外界环境的变化实时地改变自身的技术参数指标。给出该滤波器的硬件结构,介绍了该进化型硬件的基本工作原理。运用一种改进的多目标自适应遗传算法,实现进化型状态变量滤波器参数优化。采用级联法所构成的高[Q]值四阶状态变量滤波器能够满足其在阻带、通带以及过渡带方面的性能要求,对其实效性进行了仿真和验证,进化的参数值符合理论结果,仿真的结果令人满意。     

基于FPGA的四阶IIR数字滤波器

采用FPGA实现四阶IIR数字滤波器,通过两个二阶节级联构成数字椭圆低通滤波器。通带内波纹小于0.1dB,阻带衰减大于32dB。     

基于随机结构的无乘法无限冲激响应数字滤波器设计方法

针对现有的无乘法无限冲激响应（ⅡR）数字滤波器设计方法存在结构固定、滤波器性能不佳的问题,提出了一种基于随机结构的无乘法ⅡR数字滤波器设计方法。该方法使用加入移位器的稳定二阶子系统直接进行无乘法滤波器的结构设计。首先,无乘法数字滤波器的结构编码被随机创建;然后,利用一种加入成功父代选择框架的差分进化算法（SPS-DE）对生成的无乘法滤波器结构进行优化。该方法实现了无乘法滤波器结构的多样化设计,而且SPS-DE算法因采用成功父代选择框架机制,具有很好的种群开发与勘探能力,在无乘法滤波器的结构优化上取得了很好的效果。与现有的无乘法ⅡR数字滤波器设计方法相比,该方法设计的无乘法ⅡR滤波器通带波纹减小了43%,阻带最大衰减下降了40.4%。实验结果表明所提方法设计的无乘法ⅡR滤波器满足结构要求并且拥有优良的性能。     

粒子群优化算法在FIR数字滤波器设计中的应用

介绍了基于粒子群优化算法的FIR数字滤波器的设计方法,并用该方法设计了一个高通滤波器。与用Parks-McClellan算法设计的高通滤波器进行了对比,发现基于粒子群优化算法的FIR滤波器的通带波动更小,阻带衰减更大。将用这两种算法设计的滤波器作用于混频信号,得出的结果也证明了基于粒子群优化算法的FIR滤波器的有效性。     

FMT系统的滤波器组优化设计

传统滤波多音调制(FMT)系统的原型滤波器阻带衰减不够大,过渡带宽度衰减速度慢,导致系统性能较低。为此,提出一种基于FMT系统载波间干扰抑制的滤波器组优化设计方法。通过优化滤波器组中原型滤波器的通带截止频率、过渡带宽度和旁瓣峰值来提高FMT系统的子信道频谱约束性。仿真结果表明,采用该优化方法设计的原型滤波器具有较小的过渡带宽度和旁瓣峰值,对应的FMT系统具有更好的子信道频谱约束性和误码率性能。     

模拟退火与遗传算法结合的数字FIR滤波器硬件进化算法

为提高数字FIR滤波器进化硬件的寻优性能,将模拟退火与遗传算法结合的新型算法作为其进化算法.该算法是在对进化硬件种群进行遗传算法操作之后,从种群中选择适当的个体进行模拟退火操作,退火的温度随着遗传算法进化代数的增加而逐步降低,直至达到优化目标.为满足算法处理能力的要求,硬件系统采用平台式FPGA的可编程SoC结构.仿真实验结果表明：以模拟退火算法为辅助的遗传算法比单纯的遗传算法在数字FIR滤波器进化系统上有着相当的优势.     

AN OPTIMAL DESIGN OF IIR DIGITAL FILTER USING PARTICLE SWARM OPTIMIZATION

In this article, a novel approach for infinite-impulse response (IIR) digital filters using particle swarm optimization (PSO) is presented. IIR filter is essentially a digital filter with recursive responses. Because the error surface of digital IIR filters is generally nonlinear and multimodal, so global optimization techniques are required in order to avoid local minima. This study is based on a heuristic way to design IIR filters. PSO is a powerful global optimization algorithm introduced in combinatorial optimization problems. This study finds the optimum coefficients of the IIR digital filter through PSO. It is found that the calculated values are more optimal than the FDA tool and GA available for the design of the filter in MATLAB. Design of low-pass and high-pass IIR digital filters is proposed in order to provide an estimate of the transition band. The simulation results of the employed examples show an improvement on the transition band. The stability of designed filters is described by the position of Pole-Zeros.     

Marquardt optimization method to design two-channel quadrature mirror filter banks

This paper proposes an efficient method for the design of two-channel, quadrature mirror filter (QMF) bank. The design problem is formulated to minimize an objective function, which is a linear combination of pass-band error and stop-band residual energy of the low-pass analysis filter of the filter bank, and the square error of the overall transfer function of the QMF bank at the quadrature frequency. A new algorithm has been developed to minimize the objective function by optimizing the filter tap weights by using Marquardt optimization method. Simulation results of the algorithm show that the performance of the proposed method is better than that of the already existing methods.     

基于FPGA的时变带宽数字滤波器的研究和设计

介绍了一种采用切比雪夫逼近算法估计滤波器的系统传输函数、按照频率乘积法基于FPGA实现窄带FIR数字滤波器的方法。通过分析设计指标中对纹波和阻带衰减的要求,确定了以切比雪夫逼近算法作为理论基础,采用MATLAB数学工具实现该算法;采用VHDL硬件描述语言描述了频率乘积法的RTL级实现结构,并通过了硬件电路测试满足了设计的要求。通过本论文论证了切比雪夫逼近法在FIR滤波器基于FPGA设计可行性。     

Laguerre discrete-time filter design

The design of discrete-time ideal filters by finite impulse response (FIR) method requires long FIR filter structures.This is due to the infinite impulse response characteristics of the ideal filters. Optimum Laguerre filter structures with smaller length can be used instead of FIR filters to reduce the order of the filters.In this paper the method of designing optimum Laguerre ideal low-pass, band-pass, high-pass, and band-reject filters is introduced. The optimization is performed by evaluating the Laguerre parameter and coefficients when the mean-square-error between the frequency response of the desired filter and its corresponding Laguerre network frequency response is minimum. The problem with the Laguerre filter design is the complexity of computations for evaluating the optimum Laguerre parameter. This complexity is reduced to one half by introducing a lemma.Both, analytical and numerical solutions are presented and the results are illustrated via some examples. The corresponding results yield a reduced filter order, and appropriate linear phase, with lower ripples in stop-band and pass-band compared to the conventional FIR filters.     

A New Design Approach for Nearly Linear Phase Stable IIR Filter using Fractional Derivative

In this paper,a new design method for digital infinite impulse response(IIR)filters with nearly linear-phase response is presented using fractional derivative constraints(FDCs).In the proposed method,design problem of an IIR frlter is constructed as the minimization of phase error between the desired and designed phase response of an allpass filter(APF)such that the designed lowpass filter(LPF)or highpass frlter(HPF)yields less passband(ep),and stopband errors(es)with optimal stopband attenuation(As).In order to have accurate passband(pb)response,FDCs are imposed on appropriate reference frequency,where the optimality of these FDCs are ensured by using a new greedy based sorting mechanism.The simulated results reflect the efficiency of the proposed method in term of improved passband response along with better transition width.However,small reduction in^is observed within the allowable limit,when compared to noin-fractional design approach,but the designed filter remains immune to wordlength(WL)effect.     

基于粒子群优化算法的模拟滤波器设计

采用传统的网络综合法设计计波器存在带宽不精确及阻带衰减过小的问题,为此,提出一种基于粒子群优化算法的无源模拟滤波器优化设计方法.在网络综合法设计的滤波器电路基础上,利用粒子群优化算法对滤波器的整个参数空间进行高效并行搜索直到获得最优的参数值.实例表明,采用该方法设计的滤波器带宽更加准确,且具有更加陡峭的阻带衰减.     

一种用于电流测量的椭圆滤波器的仿真与设计

针对控制器电流测量电路输入信号存在纹波电流干扰的问题,设计了一种基于运算放大器的椭圆有源低通滤波器。该滤波器截止频率为10 Hz,通带增益为40 dB,对其进行了仿真分析,并且与同样性能指标的普通滤波器进行了比较,椭圆滤波器的幅频响应曲线在通带内增益平稳,过渡带特性较窄。