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7-21
Operating Concepts
S-Parameters
Figure 7-3 S-Parameters of a Two-Port Device
S-parameters are exactly equivalent to these more common description terms, requiring
only that the measurements be taken with all test device ports properly terminated.
S-Parameter Definition Test Set Description Direction
S
11
b
1
/a
1
a
2
= 0 Input reflection coefficient FWD
S
21
b
2
/a
1
a
2
= 0 Forward gain FWD
S
12
b
1
/a
2
a
1
= 0 Reverse Gain REV
S
22
b
2
/a
2
a
1
= 0 Output reflection coefficient REV