u(t) < 1 or u(jw) < 1 ?

From: Sigurd Skogestad <skoge@chemeng.ntnu.no>
Date: Wed Jun 05 2002 - 08:25:48 CEST

At 22:19 03.06.2002 -0600, you wrote:

Dear Professor Sigurd Skogestad:
 
I am a PhD student in the ECE department, University of Wyoming,USA. I really like your book "multivariable feedback control". It covers so many practical things that not even mentioned in other books.
 
However i have i a quick question, could you please take one minute or two and give me a brief explanation.
 
On page 189-190, "Limitations imposed by input constraints". We require that |u(t)|<1,which is defined time domain, however later it becomes |u(w)|<1. Can we get |u(t)|<1 from |u(w)|<1 ?

The reason is that we here are considering sinusoidal signals so |u(t)<1| is equivalent to |u(jw)<1|. i am sorry that this is not written very clearly.

 
Thanks
 
Haomin Lin

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Received on Wed Jun 5 08:25:51 2002