By Topic

On spectral mappings, higher order circle criteria, and periodically varying systems

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

2 Author(s)
Zames, G. ; Department of Transportation, Cambridge, MA, USA ; Kallman, R.

For feedback equations of the form e = x - He , in which H is a linear operator, stability boundaries obtained by the circle criterion method can frequently be improved by finding a function f(H) which conformally maps the spectrum of H from its initial region in the complex plane into a more suitable region. This idea, which is based on the spectral mapping theorem of Banach algebras, is applied here to a class of equations consisting of a time-invariant part and a periodically time-varying gain. A stability bound is derived which has a minimum whenever the frequency response of the time-invariant part peaks at a frequency near one half that of the time-varying gain.

Published in:

Automatic Control, IEEE Transactions on  (Volume:15 ,  Issue: 6 )