Title
Criteria For Determining The Optimal Levels Of Multilevel Perturbation Signals For Nonlinear System Identification
Abstract
A method is developed for determining the optimal levels of multilevel perturbation signals for nonlinear system identification, using the condition numbers of matrices derived from a Vandermonde matrix of the set of signal levels. It is applicable to the identification of nonlinear systems when the perturbation signal is applied directly to a static nonlinearity. The optimal signal level sets of size q obtained when the order of the nonlinearity is q - 1 are virtually identical to those obtained previously for Volterra series models by a more complex method. With the new method, optimal signal level sets can also be obtained for every order of nonlinearity less than q - 1, in most of which the number of different signal levels is less than the signal level set size q. The results indicate that, for nonlinear system identification, a confidence limit is reached when 7-level signals are used for the identification of 6-th order nonlinearities. They also show that, for the identification of an r-th order nonlinearity, there is little point in using signals with more than r + 1 different levels, although in most cases the size of the optimal signal level set that contains these levels will be,greater than r + 1. The method gives optimal signal level sets that are independent of the number of occurrences of the signal level set during a measurement period. Their values are shown to be the global optima for pseudo-random perturbation signals derived from maximum-length sequences, in which the zero level occurs one time less than the other levels during a period. For periods of 100 or more, the differences between the actual and global optima are less than 1%.
Year
DOI
Venue
2003
10.1109/ACC.2003.1240533
PROCEEDINGS OF THE 2003 AMERICAN CONTROL CONFERENCE, VOLS 1-6
Keywords
DocType
ISSN
sequences,vandermonde matrix,nonlinear system identification,robustness,confidence limit,identification,nonlinear systems,maximum length sequence,nonlinear equations,level set,signal processing,nonlinear system,condition number
Conference
0743-1619
Citations 
PageRank 
References 
3
0.61
1
Authors
3
Name
Order
Citations
PageRank
H. A. Barker152.07
Ai Hui Tan29513.21
K. R. Godfrey36818.03