Specifications

In each case, considerable time is lost due to reloading a 2-port
calibration between measurements or due to measuring 16 parameters
each time when only four are needed.
With Flexible Calibration, you can perform a full 4-port calibration
(parent calibration) to start and then enable a 2-port calibration for
each of the measurement groups. Once the parent calibration has been
performed, the Flexible Cal menu (left) can be used to select the
appropriate measurement subsets as follows:
q
FULL TERM CALS—If the parent calibration is a 4-port calibra
-
tion, use this to select a full 2 or 3-port calibration or to re-enable
the full 4-port calibration; if the parent calibration is a 3-port
calibration, use this to select any 2-port calibration or to
re-enable the 3-port calibration
q
REFLECTION ONLY CALS—Use this to select one, or up to four,
reflection-only one-port calibrations
q
CUSTOMIZE CALS—Use this to select different combinations
other than full-term or 1-port calibrations
An important point is that the system will automatically determine
which error terms must be included to perform the correction as best
as possible within the constraints supplied. The rules for the system's
decisions can be described as follows:
q
If a reflection term (S
ii
) is activated, include all reflectometer co-
efficients for that port. If S
ii
is isolated, the calibration is treated
like a 1-port reflection-only calibration
q
For each transmission term (S
ji
), activate its tracking term. If
done alone, the calibration is treated like a normalization calibra
-
tion (similar to frequency response)
q
If a transmission term is activated along with its matching re
-
flection terms (e.g., S
12
,S
11
and S
22
), activate the load match terms
The net effect is, if all four parameters associated with a 2-port
calibration are specified, a full 2-port correction will be enabled. If only
S
ii
and S
ji
are activated, then a 1-path 2-port calibration will be
enabled.
NOTE
Although the system can be fairly intelligent in which
terms it uses, it knows little about the DUT. You can help
by specifying not only the measurements that are needed,
but also the ones that are tightly connected to the desired
measurement and are not on the measurement's list.
MEASUREMENT LRL/LRM
CALIBRATION CALIBRATION
MS462XX OM 7-35