11.2. Stability criteria
In this section, we will pre sent different stability criteria for causal and semi-causal recursive filters. A stability criterion is a sufficient and necessary condition to assure BIBO stability.
We start by introducing three subsets of :
|– The open unit bidisk|
|– The closed unit bidisk|
|– The unit bi-circle or toric unit|
Here are the three subsets of :
|– The open unit disk|
|– The closed unit disk|
|- The unit circle|
Let us consider a continuous function : that does not vanish in the closed unit bidisk. It results from the continuity of |f| and the ...