多通道高保真音频信号ⅡR滤波器设计

在音频信号处理领域滤波器往往是关键的部件。而随着娱乐媒体的发展,高精度的音频信号被广泛使用,多通道更是音频信号处理的重要需求之一。基于这一强烈应用需求驱动,设计了一款基于FPGA并满足可扩展的多通道IIR滤波器。通过分析仿真测试输出数据的频谱,验证该硬件滤波器的性能满足设计要求。     

结合零点配置与分子动优化设计IIR多频陷波器

数字无限脉冲响应陷波滤波器的作用是抑制或滤除数字信号中一些特定的频率分量。在基本的二阶陷波滤波器的基础上,通过增加零极点对,设计一种新的单频陷波滤波器,设置两个极点和新增加零点的极角等于原零点的极角,新增加极点的极径等于原极点极径,以此来弥补其过渡带;调整新增加零点的极径,增大过渡带增益,使其具有更窄的过渡带,陷波效果更好。提出一种数字多频陷波器的设计方法,通过级联改进的单频陷波器,用分子动理论优化算法优化新增加零点的极径,实现具有稳定特性的陷波系统并且加快计算速度。经过一系列仿真实验,验证了所提方法的鲁棒性和实用性。     

基于改进粒子群优化算法的IIR数字滤波器设计

针对粒子群优化(PSO)算法存在早熟收敛问题,提出了一种改进算法——带有柯西扰动的重分布粒子群优化(RPSO)算法,并应用于IIR数字滤波器的优化设计。RPSO在检测到粒子群早熟收敛时,自动触发粒子重分布机制,帮助粒子逃离局部收敛区域,同时在迭代过程中对种群的全局最优位置施加柯西扰动以保持种群的多样性。仿真实验结果表明,在对IIR数字滤波器设计时,RPSO算法的性能优于粒子群、量子粒子群以及基于混沌变异的粒子群优化等算法。     

基于微粒群算法的自适应IIR滤波器的优化设计

针对自适应IIR滤波器潜在的不稳定性和性能指标函数容易陷入局部极小点而导致性能下降等问题,用一种新的优化算法-微粒群算法来对自适应IIR滤波器进行优化设计,它不依赖于梯度信息,能够有效地实现自适应IIR滤波器参数的全局寻优,仿真结果表明用微粒群算法进行参数寻优优于遗传算法,不仅解决了自适应滤波器性能指标函数容易陷入局部极小点的问题,也解决了稳定性问题。     

Artificial immune algorithm for IIR filter design

Over the recent years, several studies have been carried out by the researchers to describe a general, flexible and powerful design method based on modern heuristic optimisation algorithms for infinite impulse response (IIR) digital filters since these algorithms have the ability of finding global optimal solution in a nonlinear search space. One of the modern heuristic algorithms is the artificial immune algorithm which implements a learning technique inspired by human immune system. However, the immune system has not attracted the same kind of interest from researchers as other heuristic algorithms. In this work, an artificial immune algorithm is described and applied to the design of IIR filters, and its performance is compared to that of genetic and touring ant colony optimisation algorithms.     

A modified adaptive IIR filter design via wavelet networks based on Lyapunov stability theory

In this paper, we present a wavelet network IIR filtering system satisfying asymptotic stability in the sense of Lyapunov unlike many other gradient descent algorithms based adaptive filtering systems. The proposed system also carries the advantages of the time-frequency specific properties of wavelet networks embedded into the proposed filter dynamics. Two experiments for system identification problems corresponding to the infinite impulse response filter design are proposed. The results verified that the proposed wavelet network infinite impulse response adaptive filtering system not only performs better than gradient descent based algorithms but also performs as good as other stability theory based optimization algorithms.     

基于神经网络的线性相位FIR滤波器设计

针对FIR滤波器的神经网络设计法,提出一种泛函连接人工神经网络的改进算法。通过设置不同的加权误差函数值来控制各个样本的学习率,改善了网络的学习效果;制定了神经网络训练集的选取规则,使用该规则选取样本对网络进行训练,可设计通带阻带截止频率指标精确可控的滤波器,克服了现有算法只能设计具有通带截止频率的滤波器和不能精确控制任意截止频率的不足。仿真结果表明所提出的方法能很好地满足设计要求。     

自适应IIR滤波器设计策略研究

根据IIR滤波器存在突出的缺点,对自适应IIR滤波器设计进行策略性研究。分别讨论输出误差法(OEM)和方程误差法(EEM)在设计自适应滤波器的应用。通过对仿真结果进行分析比较,修正的EEM克服OEM在设计结果中存在多个局部极小值的不足,优于OEM。从而提出设计自适应滤波器的策略和实现途径。     

Novel multiband ring coupler based on notch filter

A novel method for designing a multiband rat‐race ring coupler based on a notch filter is proposed. This method realizes dual‐, tri‐, quad‐, penta‐, … band characterizes of coupler using the same structure, two additional branches. So, it has three advantages: (a) simple structure even the number of working bands more than four; (b) achieving the different numbers of working bands with just one structure; (c) useful for almost any kind of wideband passive components because it views them as black boxes. Three prototypes, a tri‐band ring coupler (Global System for Mobile Communications 0.9 GHz, Digital Communication System 1.8 GHz, Industrial Scientific Medical 2.45 GHz), a quad‐band ring coupler (Time Division Long‐Term Evolution 2.3 GHz, Satellite C‐Band Downlink 3.8 GHz, Aeronautical Radio Navigation 4.3 GHz, and Satellite C‐Band Uplink Applications 6.3 GHz) and a penta‐band ring coupler (Frequency Division Long‐Term Evolution [LTE‐FDD] 0.9, 1.4, 1.8, 2.3, and 2.6 GHz), are simulated and measured. They all use the same structure but different parameters of the added branch. The results validate the functionality of the coupler. The method of designing multiband devices in this study can be used for other passive devices, and the structure is simple.     

基于不对称陷波器的谐波电流检测方法*

为了克服常规自适应算法由于权值是一个含有二次谐波的波动量导致基本自适应算法不能准确提取出谐波电流的缺点,提出了一种基于不对称陷波器谐波电流检测方法。该不对称陷波器的实质是通过加入一个低通滤波器改变了陷波器参考频率附近的带宽,从而在保证动态相应的前提下兼顾系统的检测精度;验证了该系统是一个稳定系统,证明了改进后的不对称性,给出了参数选择的依据。通过仿真实验表明,该系统可以在一个周期内就能稳定跟随,系统的畸变率可以控制在1.7%以下。     

基于进化规划算法的IIR数字滤波器优化设计

采用进化规划算法进行IIR数字滤波器的优化设计。进化规划算法是一种模拟自然选择和变异机制的随机并行优化算法。本文首先描述了进化规划算法,并将进化规划算法用于IIR数字滤波器优化设计,模拟计算结果表明本算法具有良好的优化效果。     

基于进化规划算法的IIR数字滤波器优化设计

采用进化规划算法进行IIR数字滤波器的优化设计.进化规划算法是一种模拟自然选择和变异机制的随机并行优化算法.本文首先描述了进化规划算法,并将进化规划算法用于IIR数字滤波器优化设计,模拟计算结果表明本算法具有良好的优化效果.     

电能计量中IIR数字滤波器的FPGA设计

结合一个在电网中的实际应用--电能计量,实现了基于FPGA的IIR高通数字滤波器.利用Matlab工具软件(FDA-Tool\sptool)设计出符合应用要求的IIR滤波器,进行系数量化后给出硬件电路实现方案,用VHDL语言加以描述,编译仿真之后在Ahera公司的Cyclone系列FPGA芯片EP1C6Q240C8上完成了硬件实现.此设计扩展性好,响应速度快,精度高,完全满足电能计量应用的要求.     

伺服系统中一种新的带阻滤波器的设计

机械共振是伺服系统中普遍存在的一个问题,机械共振主要由伺服系统中功率传输元件的柔性所引起.伺服系统中标准的控制律是按照刚性耦合的负载来设计的,然而,在实际的伺服系统中柔性普遍存在,这种柔性会减小系统的稳定裕度、降低系统的性能甚至引起系统不稳定.带阻滤波器是处理机械共振的最常用的方法,本文提出了一种伺服系统中带阻滤波器设计的新方法,该方法较老方法具有明显的优点.     

Fixed-point digital IIR filter design using two-stage ensemble evolutionary algorithm

The research on optimal design of infinite-impulse response (IIR) filter design based on various optimization techniques, including evolutionary algorithms (EAs), has gained much attention in recent years. Previously, the parameters of digital IIR filters are encoded with floating-point representations. It is known that a fixed-point representation can effectively save computational resources and is more convenient for direct realization on hardware. Inherently, compared with the floating-point representation, the fixed-point representation would make the search space miss much useful gradient information and therefore, surely rises new challenges for continuous EAs. In this paper, we first analyze the fitness landscape properties of optimal digital IIR filter design. Based on the fitness landscape investigation, a two-stage ensemble evolutionary algorithm (TEEA) is applied to digital IIR filter design with fixed-point representation. In order to fully evaluate the performance of TEEA, we experimentally compare it with five state-of-the-art EAs on four types of digital IIR filters with different settings. Based on the experimental results, we can conclude that TEEA has higher convergence speed, better exploration, and higher success rate. In order to benchmark TEEA further, we apply it to some more difficult problems with shorter word length or higher order. We can find that TEEA can provide satisfying performance on these hard tasks as well.     

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(?)2范数近似的误差边界,仿真结果验证了该方法的有效性．     

基于克隆选择调节算法的IIR数字滤波器设计

在克隆选择算法的基础上．结合独特型免疫网络理论中抗体间的自适应动态调节思想,提出一种新的免疫算法——克隆选择调节算法（CSAA）．并用于IIR数字滤波器的设计．该算法能更好地保持解的多样性及收敛速度快．有效地避免了早熟现象．对多个典型系统进行随机仿真并与其他方法进行比较研究,结果表明．该算法在多模态搜索空间中具有更好的全局收敛性和稳定性．是一种有效可行的IIR数字滤波器设计方法．     

基于定点dsp的IIR滤波器溢出分析

分析了IIR滤波器在定点dsp程序设计中溢出产生的原因,提出了一种溢出的解决方法,通过提取一个缩放因子,并讨论了如何确定缩放因子的问题,来消除溢出。实验结果表明,该方法确实有效的解决了IIR滤波器设计中的溢出问题。     

基于陷波器的伺服系统共振抑制的研究

为了有效解决伺服系统中由于机械刚度低产生的机械共振,利用Matlab对伺服驱动模型进行仿真,借助FDAtool设计了2阶直接Ⅱ型陷波器,消除了伺服和负载组成的双惯性系统之间的共振频率.发现并分析了通带衰减参数对共振抑制的影响,在DSP上实现了双惯性系统的机械共振抑制控制程序,提出了陷波器在实时系统上的实现算法,并用永磁同步电机与丝杠进行实验验证,实验结果表明共振得到了抑制.