频域逼近优化的开关电流电路小波变换方法  

Method for wavelet transformation using switched-current circuit with approximation optimization in frequency domain

作　　者：童耀南[1,2] 何怡刚[1,3] 李宏民[2,3] 尹柏强[1] 

机构地区：[1]湖南大学电气与信息工程学院,长沙410082 [2]湖南理工学院信息与通信工程学院,岳阳414006 [3]合肥工业大学电气与自动化学院,合肥230009

出　　处：《电子测量与仪器学报》2014年第3期262-271,共10页Journal of Electronic Measurement and Instrumentation

基　　金：国家杰出青年科学基金(50925727);国家自然科学基金(60876022);国防科技计划项目(C1120110004;9140A27020211DZ5102);湖南省科技计划项目(2011JK2023;2013GK3096);教育部科学技术研究重大项目(313018)资助项目

摘　　要：提出了一种频域逼近优化的开关电流电路小波变换方法。利用小波函数幅度响应和相位响应信息,并考虑滤波器稳定性,设计小波基滤波器频域逼近优化模型,模型可采用常规优化算法求解。基于第二代开关电流积分器电路,构造一阶节和双二阶节基本电路模块。以五阶高斯小波基为例进行优化逼近,对逼近获得的小波基滤波器传递函数进行级联分解,并采用开关电流基本电路模块进行小波基电路综合。分析表明,五阶高斯小波逼近时域均方误差仅为2.883×10-4,频域均方误差仅为5.061×10-4。仿真结果表明,电路具有逼近效果好、小波尺度可调谐、电路灵敏度低等特点。A method for wavelet transformation using switched-current circuit with approximation optimization in frequency domain is proposed.Using the information of wavelet amplitude response and phase response,taking the stability into account,an approximation optimization model in frequency domain is designed.The optimization model can be solved in normal optimization algorithm.The first-order and biquadratic section circuits are designed based on the second generation switched-current integrator module.The fifth order Gaussian wavelet base is taken as an example for approximation.The approximated Gaussian wavelet base transfer function is decomposed in serial connection form.Then the serial connected transfer function is synthesized using the switched-current first-order and biquad-order section circuits.The analysis result shows that the approximation mean square error for fifth Gaussian wavelet is 2.883 × 10-4 and 5.061 × 10-4,in time and frequency domain,respectively.Some simulation results in dicate that the proposed circuit has the merit of high approximation accuracy,scalable wavelet waves and low circuit sensitivity.

关 键 词：开关电流电路 小波变换 小波滤波器 频域逼近 

分 类 号：TN929.52[电子电信—通信与信息系统]