R&S ZNB Series User Manual page 140

®
R&S ZNB/ZNBT
●
c: Common mode (for balanced ports)
The notation of a general S-parameter is S
denote the output and input port modes, <out> and <in> denote the output and input
port numbers.
Meaning of 2-port mixed mode S-parameters
The mixed mode 2-port S-parameters can be interpreted as follows:
●
S
the wave quantities b
ward measurement with matched output and a
●
S
ratio of the wave quantities b
ment with matched output and a
●
S
ratio of the wave quantities b
input, b
●
S
the wave quantities b
in the figure above and a
If <mout> is different from <min>, the S-parameters are called mode conversion fac-
tors.
Mixed-mode parameters for different test setups
Which types of mixed mode parameter are available depends on the measured device
and the port configuration of the analyzer. With 4 physical test ports (on the VNA and
connected
ters can be measured.
1. DUT with only single-ended ports: No balanced port definition necessary, the ana-
lyzer provides single-ended multiport parameters.
2. DUT with one balanced port: Only reflection and mode conversion measurements
with differential and common mode parameters.
User Manual 1173.9163.02 ─ 62
is the mixed mode input reflection coefficient, defined as the ratio of
<mout><min>11
(mode mout) to a
1
is the mixed mode forward transmission coefficient, defined as the
<mout><min>21
is the mixed mode reverse transmission coefficient, defined as the
<mout><min>12
' in the figure above and a
1
is the mixed mode output reflection coefficient, defined as the ratio of
<mout><min>22
(mode mout) (reverse measurement with matched input, b
2
External switch matrices), the following examples of mixed mode parame-
<mout><min><out><in>
(mode min), measured at PORT 1 (for-
1
2
(mode mout) to a
2
= 0).
2
(mode mout) (reverse measurement with matched
1
= 0) to a (mode min).
1 2
= 0) to a (mode min), measured at PORT 2.
1 2
Concepts and features
Measurement results
, where <mout> and <min>
= 0).
(mode min) (forward measure-
1
'
2
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