Appendix D Two-Port Parameter Conversion.pdf

Radio Frequency Circuit Design. W. Alan Davis, Krishna Agarwal
Copyright  2001 John Wiley & Sons, Inc.
Print ISBN 0-471-35052-4 Electronic ISBN 0-471-20068-9
APPENDIX D
Two-Port Parameter Conversion
TWO-PORT VOLTAGE AND WAVE PARAMETERS
Conversion between the z, y, h,andg two-port voltage-current parameters is
simply rearrangement of two linear equations relating voltages and currents at
the two ports. Converting between these and the S parameters requires relating the
voltage waves to voltages and currents. This latter relationship always includes
the characteristic impedance, Z0,bywhichtheS parameters are defined. Typically
this value is 50 . Table shows this conversion. The program PARCONV is
basically a code of many of the conversions in Table .
The definitions of the various two-port parameters are described below. In
each case it is assumed that the current is flowing into the port terminal.




v z z i
1 D 11 12 1
v2 z21 z22 i2




i y y v
1 D 11 12 1
i2 y21 y22 v2




v h h i
1 D 11 12 1
i2 h21 h22 v2




i g g v
1 D 11 12 1
v2 g21 g22 i2




v AB v
1 D 2
i1 CD i2




b S S a
1 D 11 12 1
b2 S21 S22 a2
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TABLE S-Parameter Conversion Chart
SzyABCD
z11  Z0
z22 C Z0
 z12z21 Y0  y11
Y0 C y22
C y12y21 A C B/Z0