R&S NRP-Z28/-Z98
Program module "Update S-Parameters"
1170.8966.12 3.7
E-1
Structure of the S2P measurement data file:
1. The
option line
has the following format (square brackets indicate that the enclosed content is
optional):
# [<frequency unit>] [<parameter>] [<format>] [<R n>]
# identifies the
option line
.
The <frequency unit> may be Hz, kHz, MHz or GHz. If a frequency unit is not specified, GHz is
implicitly assumed.
If a parameter is specified, S must be used in <parameter> for s-parameter files. If a parameter
is not specified, S is implicitly assumed.
The <format> may be MA (linear magnitude and phase in degree), DB (magnitude in dB, phase
in degree) or RI (real and imaginary part). If a format is not specified, MA is implicitly assumed.
R is optional and followed by the reference impedance in
.
If an entry is made for R, R50 must
be specified. If no entry is made, R50 is implicitly assumed.
The
option line
should therefore read:
# [HZ | KHZ | MHZ | GHZ] [S] [MA | DB | RI] [R 50]
2. The measurement frequencies in ascending order are specified as follows:
( )
( )
( )
( )
i
i
i
i
i
f
s
f
s
f
s
f
s
f
22
12
21
11
,
where
( )
i
jk
f
s
is the display format as specified in the
option line
:
( )
( )
i
jk
i
jk
f
s
f
s
arg
(display format for linear magnitude and phase in degree) or
( )
( )
i
jk
i
jk
f
s
f
s
arg
lg
20
(display format for magnitude in dB and phase in degree)
( )
[
]
( )
[
]
i
jk
i
jk
f
s
f
s
Im
Re
(display format for real and imaginary part)
3. Comments: Any line starting with an exclamation mark (!) is interpreted as a comment line.
To characterize the measurement uncertainty of the s-parameter test system, another data file can
optionally be created. The syntax of the uncertainty data file is similar to that of the S2P data file but U
is specified as <Parameter> in the
option line
so that the
option line
reads # Hz U for frequencies in Hz.
The measurement frequencies must not be identical to those of the S2P measurement data files. In
most cases a few entries will be sufficient to characterize the measurement uncertainty of the s-
parameter test system. An s-parameter uncertainty as high as that of the neighbouring measurement
frequencies of the uncertainty data file is then selected. If different values are available, the higher one
is chosen. This is illustrated in the example below:
Table 3-4
Uncertainties of the s-parameter test system (example)
f
in GHz
unc [
s
ik
(f)
]
0.1 0.01
1.0 0.01
1.1 0.005
10.0 0.005
10.1 0.01
40.0 0.01
