Reducing Mismatch Errors In A Transmission Measurement - HP 8712ES User Manual

NOTE
NOTE
Optimizing Measurements
Reducing Mismatch Errors
Reducing Mismatch Errors in a Transmission
Measurement
The best way to reduce mismatch errors in a transmission measurement
of a two-port device is to perform a two-port calibration directly at the
point that will connect to the DUT, using the exact frequency parameters
that you will be using for the measurement. Though not quite as
accurate as a two-port calibration, an enhanced response calibration can
also be used to reduce source match errors. To minimize load match
error, it is recommended that you use an attenuator on the output of the
DUT. An enhanced response calibration offers the advantage of faster
measurement speeds than when using a two-port calibration.
1. Set up your S forward transmission measurement or S
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transmission measurement, and frequency parameters.
2. Press User 2-Port
CAL
Enhanced Response
3. Follow the instructions on the display.
See Chapter 6 for more information on calibration choices for
transmission measurements.
If you choose to do an enhanced response calibration, it is recommended
that you use a high quality attenuator on the output of the DUT, as
shown in Figure 3-38 on page
sufficient to significantly reduce mismatch errors.
Using an attenuator on the output of the DUT will reduce the system
dynamic range.
5-16
or User Response
CAL
.
3-82. Six to ten dB of attenuation should be
reverse
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ES User's Guide