不确定Sigma-Delta调制器的鲁棒滤波  

Robust filtering for uncertain Sigma-Delta modulators

作　　者：王英俊[1] 王武[1] 王骞[1] 

机构地区：[1]福州大学电气工程与自动化学院,福建福州350116

出　　处：《福州大学学报（自然科学版）》2013年第1期59-65,共7页Journal of Fuzhou University(Natural Science Edition)

基　　金：福建省自然科学基金资助项目(2012J01257);福州大学科技发展基金资助项目(2012-XY-3)

摘　　要：研究级联Sigma-Delta调制器在非理想性电路中的鲁棒校正滤波器设计问题.基于MARKOV区间算法和线性区间系统的等价描述,将扰动抑制问题转化为增广系统的鲁棒稳定问题.给出以线性矩阵不等式描述的鲁棒滤波器存在的充分条件,该条件保证所设计的校正滤波器能有效抑制电路不确定性对调制器性能的影响.仿真结果表明,与传统校正滤波器相比,该调制器获得了更好的信号噪声比.方案降低了电路实现过程中器件精确度的要求,从而达到低应用成本的目的.The design of robust correction filter for cascaded Sigma - Delta modulators with analog circuit imperfection is studied. Based on MARKOV interval algorithm and the equivalent description of linear interval system, the problem related to disturbance suppression is transformed into a robust stability problem. A linear matrix inequality approach is developed to obtain the parameters of a robust filter, which guarantees that the correction filter can effectively suppress the influence of analog circuit imperfection to the modulators. Simulation results show that the modulators exhibit lower variation in the signal -to -noise and distortion ratio over the nominal correction filter. The proposed scheme decreases requirements of accuracy during the circuit implementation, then achieve the purpose of low cost application.

关 键 词：SIGMA-DELTA调制器 不确定性 MARKOV区间算法 线性矩阵不等式 

分 类 号：TP13[自动化与计算机技术—控制理论与控制工程]