5 CALIBRATION AND CALIBRATION KIT
5.8.1 Automatic Calibration Module Features
ACM allows the Analyzer software to perform full two-port or full one-port calibrations
with the click of a button. We recommend that you terminate the unusable ACM port
with a load while performing one-port calibration.
Characterization is a table of S-parameters of all the states of the ACM switches, stored
in the ACM memory. There are two types of characterization: user characterization and
factory characterization. ACM has two memory sections. The first one is write-
protected and contains factory characterization. The second memory section allows you
to store up to three user characterizations. Before calibration you can select the factory
characterization or any of the user characterizations stored in the ACM memory. The
user characterization option is provided for saving new S-parameters of the ACM after
connecting adapters to the ACM ports.
The software enables you to perform a user characterization and save the data to ACM
with the click of a button. To be able to do this, you should first calibrate the Analyzer
test ports in configuration compatible with the ACM ports.
Orientation means relating the ACM ports to the test ports of the Analyzer. While the
Analyzer test ports are indicated by numbers, the ACM ports are indicated by letters A
Orientation is defined either manually by the user, or automatically. The user is to select
the manual or automatic orientation method. In case of automatic orientation, the
Analyzer software determines the ACM orientation each time prior to its calibration or
The Thru implemented by the electronic switches inside the ACM introduces losses.
That is why you should know the exact parameters of the Thru or use an Unknown Thru
algorithm to achieve the specified calibration accuracy.
The software allows using the both options. ACM memory stores S-parameters of the
Thru, which are used to compute calibration coefficients. In case if an Unknown Thru
algorithm is applied, such parameters are disregarded.
The most accurate calibration can be achieved if the ACM temperature is equal to the
temperature, at which it was characterized. When this temperature changes, certain
ACM state parameters may deviate from the parameters stored in the memory. This
results in reduction of the ACM calibration accuracy.