§Let G(s) be a p× q transfer matrix. Then a multiplication operator is defined as MG: L2 ® L2
, MG f=Gf
• Then
•
§ Proof: It is clear that ||G||¥ is the upper bound:
§
§
• To show
that ||G||¥ is the least upper bound, first choose a
frequency w0 where is maximum, i.e.,