Shi J H, Sun H H
Department of Electrical and Computer Engineering, Drexel University, Philadelphia, PA 19104.
IEEE Trans Biomed Eng. 1990 Jun;37(6):574-87. doi: 10.1109/10.55661.
A new algorithm has been developed to identify a system divided into cascaded blocks of dynamic linear (L), static nonlinear (N), and dynamic linear (L) subsystems based strictly on the input-output relationship. The nonlinear element is assumed to be equicontinuous, or must be satisfied by the Weierstrass criterion. Therefore, it could either be continuous type as represented by polynomial approximation or abrupt type as represented by piecewise-linear segments. The process uses a series of multilevel input to decouple the two linear subsystems from the nonlinear subsystem and then applies the predictor-corrector algorithm to minimize a cost function to obtain the parameter of the subsystem. The method does not restrict the type of input signal and no prior knowledge of the subsystems is necessary. Numerical example for a prescribed system is given and the results show almost identical values by any one of the three types of input, namely: step, sinusoidal, or white noise. Three computer programs have been developed for the identification of the system with odd, even, and piecewise abrupt types of nonlinearity. The method is applied to model the interfacial phenomenon of noble metal electrode (Pt) at the nonlinear range and the algorithm is verified by comparison with the result developed previously.
一种新算法已被开发出来，用于识别一个基于输入 - 输出关系严格划分为动态线性（L）、静态非线性（N）和动态线性（L）子系统的级联块的系统。假设非线性元件是等度连续的，或者必须满足魏尔斯特拉斯准则。因此，它既可以是多项式逼近所代表的连续类型，也可以是分段线性段所代表的突变类型。该过程使用一系列多级输入来将两个线性子系统与非线性子系统解耦，然后应用预测 - 校正算法来最小化一个代价函数以获得子系统的参数。该方法不限制输入信号的类型，并且不需要子系统的先验知识。给出了一个规定系统的数值示例，结果表明三种类型的输入（即阶跃、正弦或白噪声）中的任何一种得到的值几乎相同。已经开发了三个计算机程序来识别具有奇数、偶数和分段突变类型非线性的系统。该方法被应用于模拟贵金属电极（Pt）在非线性范围内的界面现象，并且通过与先前得到的结果进行比较来验证该算法。
