A class of nonlinear filtering problems arising from drifting sensor gains

Author

Vincent, Tyrone L. ; Khargonekar, Pramod P.

Author_Institution

Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI, USA

Volume

44

Issue

3

fYear

1999

fDate

3/1/1999 12:00:00 AM

Firstpage

509

Lastpage

520

Abstract

This paper considers a state estimation problem where the nominal system is linear but the sensor has a time-varying gain component, giving rise to a bilinear output equation. This is a general sensor self-calibration problem and is of particular interest in the problem of estimating wafer thickness and etch rate during semiconductor manufacturing using reflectometry. We explore the use of a least squares estimate for this nonlinear estimation problem and give several approximate recursive algorithms for practical realization. Stability results for these algorithms are also given. Simulation results for comparing the new algorithms with the extended Kalman filter and iterated Kalman filter are given

Keywords

calibration; filtering theory; integrated circuit manufacture; least squares approximations; maximum likelihood estimation; nonlinear systems; observers; optimisation; sensors; approximate recursive algorithms; calibration; least squares estimate; nonlinear filtering; nonlinear systems; observers; semiconductor manufacturing; sensor; state estimation; time-varying gain; Etching; Filtering; Least squares approximation; Nonlinear equations; Recursive estimation; Reflectometry; Semiconductor device manufacture; Sensor systems; State estimation; Time varying systems;

fLanguage

English

Journal_Title

Automatic Control, IEEE Transactions on

Publisher

ieee

ISSN

0018-9286

Type

jour

DOI

10.1109/9.751345

Filename

751345