Agilent Technologies N4413A, User Manual

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Using the Multiport Test System
How to Measure Simultaneous Conjugate Match of a Device with One Single-Ended and One Differential Port
Chapter 3 74
How to Measure Simultaneous Conjugate Match of a Device
with One Single-Ended and One Differential Port
Calculating the simultaneous conjugate match of a device with one single-ended port is done
in a very similar manner as a device with a simple parameter substitution. For example, if the
DUT is configured as follows:
then, compared to a device with two differential ports, substitute S
11
for S
DD11
, S
DS21
for
S
DD21
, and S
SD12
for S
DD12
. Therefore,
where n=1 for port 1 and n=2 for port 2.
K
1 S
11
2
– S
D D 22
2
– D
2
+
2 S
D D 12
S
D D 21
⋅ ⋅
--------------------------------------------------------------- =
D S
11
S
D D 22
⋅
S
D S 21
– S
S D 12
⋅
=
C
1
S
11
S
D D 22
– =
B
1
1 S
D D 22
2
– S
11
2
D
2
– + =
C
2
S
D D 22
S
11
– =
B
2
1 S
11
2
–
S
D D 22
2
D
2
– + =
Γ
G Mn
C
n
C
n
---------
B
n
2 C
n
------------
B
n
( )
2
2 C
n
2
---------------
1 – –
⋅
=