Agilent Technologies 8719D, User Manual

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Calibrating for Non-Insertable Devices
A test device having the same sex connector on both the input and output cannot be
connected directly into a transmission test configuration. Therefore, the device is considered
to be and one of the following calibration methods must
be
performed.
For information on performing measurement calibrations, refer to Chapter 5, “Optimizing
Measurement Results.
Adapter Removal
The adapter removal technique provides a means to accurately measure the noninsertable
device. For each port, a error correction needs to be performed to create a calibration
set. The adapter removal algorithm uses the resultant data from the two calibration sets and
the nominal electrical length of the adapter to compute the adapters actual S-parameters. This
data is then used to generate a separate third set in which the forward and reverse match
and tracking terms are as if Port 1 and Port 2 could be connected. This is possible because the
actual S-parameters of the adapter are measured with great accuracy, thus allowing the effects
of the adapter to be completely removed when the third set is generated.
Matched Adapters
With this method, you use two precision matched adapters which are “equal.” To be equal, the
adapters must have the same match, insertion loss, and electrical delay.
Modify the Cal Kit Definition
With this method it is only necessary to use one adapter. The calibration kit thru definition is
modified to compensate for the adapter and then saved as a user kit. However, the electrical
delay of the adapter must first be found.
Application and Operation Concepts
07