### Optimization and Systems Theory Seminar

Friday, July 19, 2002, 11.00-12.00, Room 3721, Lindstedtsvägen 25

**Associate Professor Hisaya Fujioka **

Department of Applied Analysis and Complex Dynamical Systems

Graduate School of Informatics

Kyoto University

Kyoto, Japan

E-mail: fujioka@i.kyoto-u.ac.jp

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Computation of frequency response gain of sampled-data systems

Sampled-data control theory has been successfully developed in the
last decade, and now we can take into account of intersample behavior
in both analysis and synthesis of sampled-data feedback control
systems.
Among them, one of the most fundamental results is the introduction of
the notion of the frequency response to sampled-data systems. In
spite of its importance on analysis and synthesis of sampled-data
systems, it is hard to compute the gain of the frequency response.
Several formulas for upper and lower bounds and approximations are
found in literature. Bisection algorithms with some assumptions are
also proposed.

This paper also deals with the frequency response gain of sampled-data
systems. To be more concrete, we will derive a condition to determine
that the gain is less than a certain positive number or not, which is
immediately applicable for a bisection computation of the gain. The
derived condition is free from assumptions required in the existing
results.

Calendar of seminars

*Last update: June 25, 2002 by
Anders Forsgren,
anders.forsgren@math.kth.se.
*