4-7 Calibration Considerations VNA Measurements
4-16 PN: 10580-00289 Rev. K Vector Network Analyzer MG
4-7 Calibration Considerations
Various 2-port calibrations are available in the Vector Network Analyzer. Transmission
response is the simplest and requires only one connection during calibration, but it does not
correct for test port match errors. 1-Path 2-Port calibration requires four calibration
connections and corrects for the transmit port match, but does not correct for the receive port.
Full 2-port calibration requires seven calibration connections and corrects for both test port
match errors (refer to Figure 4-14). The full 2-port calibration technique offers the most
accuracy.
For accurate results, the instrument must be calibrated at the ambient temperature after
allowing for warm up time (approximately 15 minutes) and before making any
measurements. The instrument must be recalibrated whenever the setup frequency changes,
whenever the ambient temperature changes by an amount that has more than likely
rendered the calibration invalid, or whenever a test port extension cable is added, removed, or
replaced. Refer to “Calibration Data and Indications” on page 4-19.
You can save a Setup with calibration (refer to the file management instructions in the user
guide for your instrument). In the Save menu, press the Change Type soft key to open the
Select File Type list box. Scroll to Setup(withCAL) and press the Enter key.
When you recall a setup, the calibration remains valid if instrument conditions (such as
temperature) remain within the calibration tolerance.
Note
The previously described calibration considerations omit isolation steps in which
loads are connected to each test port. During the isolation step of the calibration
procedure, the Vector Network Analyzer measures the isolation between test ports
in order to achieve best dynamic range performance.
Note
The Vector Network Analyzer Calibration menu is the same one that is used in the
Vector Voltmeter menu. Refer to section “Calibration Menu” on page 6-19 for more
information about the calibration menu. Note that some calibration parameters are
shared between the Vector Network Analyzer and Vector Voltmeter mode, and that
some parameters are different because they were optimized for the specific mode
application.
Caution
Changing from VNA Measurement mode to Field Measurement mode invalidates
the instrument calibration.
To Next Page
Loading...
