China Electronics Technology Instruments AV3672 Series, User Manual

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7 Calibration
7.4 High-accuracy Measurement Calibration
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frequency range of calibration in the [Min Freq] and [Max Freq] input box. The standard calibration kit button in
the [THRU Resp and Isol] dialog box will become green after isolation calibration.
Fig. 7.7 [Multiple Standards] Dialog Box
8) Click [OK] in the [THRU Resp and Isol] dialog box after calibration.
Fig. 7.8 [Through type response and isolation calibration] Dialog Box
Notes: 1. The optional calibration type is associated with the measurement parameters of the current active channel.
For example, if the measurement parameter is S
11
, the through type response mode or the through type response
and isolation calibration mode cannot be selected.
2. If isolation calibration is not required in the full 2-port calibration, tick the [Ignore isolation (2-port type)]
check box.
Attention
Properly select the calibration standard to realize the highest calibration accuracy.
The [Measurement of multiple standard kits] dialog box shows the standard connector types, instead of the
connector types for non-test ports. In order to realize the highest calibration accuracy, the calibration standard must
be selected properly.
7.4 High-accuracy Measurement Calibration
The calibration accuracy depends on the selected calibration type, calibration kit quality and calibration process.
This section mainly discusses how to perform high-accuracy calibration.
1) Measurement reference plane
The DUT is not directly connected to the port of the analyzer in most of measurements. Instead, it is connected
through the test fixture or cable. The connection point of the DUT must be calibrated to realize the highest
measurement accuracy. This point is recalled the measurement reference plane. If the measurement reference plane
is calibrated, the error related to the measurement composition (such as the cable, test fixture and adapter between
the analyzer port and reference plane) can be measured and eliminated.
2) Influence of calibration kit
Under normal conditions, the calibration standard of the calibration kit is the same as the connector type standard of
the DUT. In some cases, however, the calibration kit corresponding to the connector type of the DUT is not
provided. For example, the port size of the DUT is 2.4mm, but the connector size of the analyzer and calibration kit
is 3.5mm. If the 2.4mm calibration kit is used for calibration and the 2.4mm/3.5mm adapter is used in measurement,