In this section it is demonstrated how to create a sector-bounded and slope-restricted nonlinearity block. To do so, suppose that this nonlinearity has the following properties:
- Name: ‘delta’
- Operator type: , is a three times repeated nonlinearity satisfying the constraints:
- Sector constraint:
- Slope constraint:
- The nonlinearity is an odd function.
- Input channels of connecting the uncertainty block:
- Outputs channels of connecting the uncertainty block:
This uncertainty can be created as follows:
delta = iqcdelta('delta','LinNonlin','NL','InputChannel', 1:3,'OutputChannel',1:3,'SectorBounds',[0,1],'SlopeBounds',[0,1],'Odd','yes');
In a next step, you have to assign an IQC-multiplier. The appropriate class for this is called usbsr (for details see here).
Now suppose you want the basis function have the following properties:
- Length: 3 (this corresponds to a McMillan degree of 2)
- Pole location: -1
This can be specified as:
delta = iqcassign(delta,'usbsr','Length',3, 'PoleLocation',-1);