A full three-port calibration (SOLT) involves twelve connections of the standards. This calibration combines three full one-port calibrations for each port, with measurements of a THRU standard between three port pairs, which provides three transmission measurements. One out of three THRU measurements can be omitted (See Simplified Full Three/Four-Port Calibration). If optional isolation calibration is required, connect LOAD standards to each test port pair of the Analyzer and perform three isolation measurements.
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For isolation calibration, set a narrow IF bandwidth and firmly attach the cables. |
Full three-port calibration allows for correction of all the twenty seven error terms of a three-port error model (acquisition of isolation terms can be omitted). For a detail descriptions, see Three-Port Error Model.
Full three-port calibration is a highly accurate method of calibration for three-port DUT measurements.
Before starting calibration perform, select an active channel, set the parameters of the channel (frequency range, IF bandwidth, etc), and select the calibration kit.
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To open full three-port calibration submenu, use the following softkeys: Calibration > Calibrate > 3-Port SOLT Cal |
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Select the port pair to be calibrated using Select Ports softkey. |
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For each of the 3 ports, repeat the following: •Click Port n Reflection softkey. •Connect SHORT, OPEN and LOAD standards to the selected port in any consequence. Perform measurements clicking the softkey Open, Short, Load corresponding to the connected standard. The instrument status bar will indicate Calibration in progress... when the measurement is in progress. On completion of the measurement, a check mark will appear in the left part of the softkey. |
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For the 3 pairs of ports (or for 2 pairs in case of the simplified calibration) repeat the following: •Connect a THRU standard between the test ports. If the port connectors allow through connection, connect them directly (zero electrical length thru). •Perform measurement using the n–m Thru softkeys. The instrument status bar will indicate Calibration in progress... when the measurement is in progress. On completion of the measurement, a check mark will appear in the left part of the softkey. Upon completion of the two measurements, the label on the remaining softkey changes to Optional, what indicates that for simplified calibration a sufficient number of measurements have been performed. |
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To perform the optional isolation calibration, connect two LOAD standards to the n and m test ports and enable measurement using the following softkeys: Calibration > Calibrate > 3-Port SOLT Cal > Isolation (Optional) > Port n-m The instrument status bar will indicate Calibration in progress... when the measurement is in progress. On completion of the measurement, a check mark will appear in the left part of the softkey. |
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To complete the calibration procedure, click Apply softkey. This will activate the process of calibration coefficient table calculation and saving it into the memory. The error correction function will also be automatically enabled. |
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To clear the measurement results of the standard, click Cancel. This softkey does not cancel the current calibration. To disable the current calibration, turn off the error correction function (See Error Correction Disabling). |
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The calibration status can be checked in channel status bar (See General error correction status table) or in trace status field (See Trace error correction status table). |
