Rohde & Schwarz 1332.4500.22, Руководство пользователя

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Concepts and Features
R&S
®
ZNA
117 User Manual 1178.6462.02 ─ 12
Chapter 5.3.6.2, "Mixed Mode Parameters" , on page 115). The general definition of the
complex CMRR between two ports (at least one of them balanced) is given below.
Imbalance and common-mode rejection ratio measurements can only be measured on
a 4-port R&S
ZNA.
General Definition
In general, imbalance and CMRR are quantities with two numeric indices, indicating
the logical output port and the logical input port of the DUT during the measurement
(Imb
<out><in>
, CMRR
<out><in>
).
●
DUT with single-ended logical port i and balanced logical port j:
DUT
Balanced
port
Log.
NWA
port
Single-
ended
port
Physical port c
Logical port j
(balanced)
Physical port d
Logical port i
(single-ended)
Physical port a
– Imb
ji
= –S
ca
/S
da
and Imb
ij
= –S
ac
/S
ad
– CMRR
ji
= S
dsji
/S
csji
and CMRR
ij
= S
sdij
/S
scij
●
DUT with balanced logical ports i and j:
DUT
Balanced
port
Log.
NWA
port
Balanced
port
Log.
NWA
port
Physical port c
Logical port j
(balanced)
Physical port d
Logical port i
(balanced)
Physical port a
Physical port b
– Imb
ji
= –(S
ca
– S
cb
)/(S
da
– S
db
), for i
≠
j
– CMRR
ji
=S
ddji
/S
ccji
Differential Imbalance
A (differential) imbalance can also be calculated if the second balanced DUT port is
connected to two single-ended logical ports:
DUT
Balanced
port
Balanced
port
Log.
NWA
port
Physical port c
Logical ports j,k
(single-ended)
Physical port d
Logical port i
(balanced)
Physical port a
Physical port b
Imb
jk-i
= –(S
ca
– S
da
)/(S
cb
– S
db
)
Imb
i-jk
= –(S
ac
– S
ad
)/(S
bc
– S
bd
)
Measurement Results