Specifications

Test Port Cable Converters (Anritsu series 36583) are used during and
after the calibration process to establish the desired test port
connector type.
9-3 CALIBRATIONS
Four types of calibration can be performed using AutoCal:
One-Port: S
11
1-Port and S
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1-Port are 1-port calibrations
performed on the indicated port of the VNMS and are equivalent to
the traditional Open-Short-Load calibrations.
Full 2-Port: This type is equivalent to the traditional
Open-Short-Load-Thru (OSLT) calibration.
Thru Update: This type is a new form of calibration which is used to
update an existing 12-term calibration in the VNMS. This calibration
could have been performed using any method of calibration which
yields 12 terms (LRL, LRM, AutoCal, or OSLT). Due to cable
movement and aging, the calibration may have degraded over time.
The Thru Update refreshes the calibration by measuring a Thru
connection and updating the Transmission Tracking and Load Match
calibration constants.
Adapter Removal: This calibration measures the characteristics of
male-male or female-female test port cables for subsequent
measurement of non-insertable devices. An adapter is required for this
calibration. Adapter Removal requires two calibration procedures in
order to calculate the parameters and electrical length of the adapter.
NOTE
If a full frequency range calibration is not required, modify
the VNMS Setup Menu to reflect only the needed range.
This will be useful when calibrating a 6 GHz or 9 GHz
VNMS below 6 GHz or 9 GHz, respectively.
9-4 DEFINITIONS The following terms are used in explaining the calibration procedure
using the AutoCal module:
Thru: A thru is a connection of the two test ports. Two kinds of thru
connections are defined for the AutoCal calibration: (1) a Calibrator
thru is an internal path through the calibrator. (2) a True thru is a
direct cable connection between the test ports, with no intervening
connectors. The calibrator thru is not as accurate as a true thru, so the
user has the option during a calibration to use the more accurate
method, if necessary.
Isolation: For certain measurements which require accurate S
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or S
12
readings for very small values of those parameters, an isolation step is
required to characterize the leakage of the VNMS and test setup. The
CALIBRATIONS AUTOCAL
9-4 MS462XX OM