Directivity Error (Ed) - Agilent Technologies E5071C Manual

Directivity error (Ed)

Directivity errors are caused by the fact that, in a reflection measurement,
signals other than the reflection signal from the DUT are received by
receiver T1 through the directivity coupler. When a certain port is a
stimulus port, this error can be defined as a constant value for each
stimulus port because the state of the termination at the other ports does
not change. The number of directivity errors of the E5071C is the number
of stimulus ports you use.
Ed1 Directivity error of port 1
Ed2 Directivity error of port 2
Ed3 Directivity error of port 3
Ed4 Directivity error of port 4
Isolation error (Ex)
Measurement
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