Appendix E
Two-Port Network Parameters
A microwave network with two terminals may be analyzed by considering the network as an equivalent two-port. The signals at the terminals or ports of the two-port may be described in terms of voltages and currents and the interaction between these signals in terms of impedances or admittances. Alternatively, the signals may be described in terms of incident and reflected waves and the interaction in terms of scattering.
An arbitrary two-port may be described in several ways. Here we will discuss the two-port in terms of impedance parameters (Z), admittance parameters (Y), chain or ABCD parameters and scattering parameters (S).
For the description in terms of Z, Y or ABCD parameters we refer to Figure E.1(a). For the description in terms of S parameters we refer to Figure E.1(b).
Figure E.1 Two-port definition. (a) Using voltages and currents. (b) Using incident and reflected waves.
The relation between the voltages and currents in terms of impedance parameters is given by
E.1 
The relation between the currents and voltages in terms of admittance parameters is given by
E.2 
The relation between the voltages and currents in terms of chain parameters ...
