Re: chapter 8 in discrete time?

Dear Josh,

I would have made a continous-time version and proceeded, but
what you suggest may be OK (I will ask my coauthor).

Both of these methods will only be an approximation, though.
(but most likely OK!)

To handle the discrete case exactly you would need to use the state-space
mu test descibed on page 345 in the book.

Good luck.

-Sigurd Skogestad

>>From kanterjm@seas.upenn.edu Mon Dec 21 23:55:39 1998
>Delivered-To: skoge@ona.chembio.ntnu.no
>
>Hi again!
>
>I was wondering if you had any advice on the following:
>
>I have a discrete time MIMO system,H(z) and I'd like to check the robust
>stability and robust performance conditions in chapter 8. How do I do
>this? Do I just replace s=iw with z=exp(Tiw), replace lhp with inside
>the unit circle, and replace for all w with 0<=w<=pi/T?
>
>I've been looking all over the book and all your references, but I
>haven't found anmything about testing robust stability and robust
>performance for discrete time MIMO systems. ANY ADVICE WOULD BE GREATLY
>APPRECIATED!!!
>
>Thanks for your time and happy holidays
>
>Josh
Received on Tue Dec 22 07:35:08 1998