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6-4 ET User’s Guide
Calibrating for Increased Measurement Accuracy
Measurement Calibration Overview
The analyzer has several methods of measuring and compensating for
these test system errors. Each method removes one or more of the
systematic errors using an equation called an error model. Measurement
of high quality standards (short, open, load, and through, for example)
allows the network analyzer to solve for the error terms in the error
model. The accuracy of the calibrated measurements is dependent on the
quality of the standards used for calibrating. Since Hewlett-Packard
calibration standards are very precise, great accuracy is achieved.
When you perform a calibration, the analyzer calculates the difference
between measurement data of known calibration standards and ideal
measurement data to create error correction arrays. The network
analyzer uses these error-correction arrays to correct subsequent
measurement data.
To see all of the calibration choices available for measurements, refer to
Table 6-1, “Calibration Choices,” on page 6-8 .
To perform a quality calibration:
• Use the highest quality standards available and take care of them.
• When performing a one-port reflection calibration or an enhanced
response calibration, be sure to select the correct cal kit by pressing
.
• Make consistent connections of the standards and DUTs (if possible,
use a torque wrench when using 3.5 mm connectors).
• Minimize temperature variations.
• Use high-quality cables (semi-rigid cables, for example).
• Minimize movement of cables.
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