Patent ID: 7801698

Claim:
A testing apparatus, comprising: an input port; a first node; a first coupling capacitor coupled between the input port and the first node; a first voltage source coupled to the first node; a second node; an output port; a second coupling capacitor coupled between the second node and the output port; a second voltage source coupled to the second node; a plurality of switched links of different lengths coupled in series between the first node and the second node, each of the plurality of switched links comprising: an input terminal; an output terminal; a first transmission line having a first end and a second end; a second transmission line having a third end and a fourth end; a first diode having (1) a first anode coupled to the input terminal and (2) a first cathode coupled to the output terminal; a second diode having (1) a second anode coupled to the input terminal and (2) a second cathode coupled to a first end of the first transmission line; a third coupling capacitor coupling the second end of the first transmission line and the third end of the second transmission line; a third diode having (1) a third anode coupled to the fourth end of the second transmission line and (2) a third cathode coupled to the output terminal; a third voltage source coupled to the first transmission line; a fourth voltage source coupled to the second transmission line.