Agilent Technologies 4395A, Manual Change

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Calibration for Network Measurement
Reection Tracking, E
RF
Reverse
Directivity , E
DR
Isolation, E
XR
Source Match, E
SR
Load Match, E
LR
Transmission Tracking, E
TR
Reection Tracking, E
RR
The 87511A, B S-parameter T est sets can measure both the forward and reverse characteristics
of the test device without the need to manually remove and physically reverse it. With these
test sets , the full two-port error model illustrated in Figure A -40 eectively removes both the
forward and reverse error terms for transmission and reection measurements .
The 87512A, B Transmission/Reection T est kits cannot switch between forward and reverse
directions , so the reverse error terms cannot be automatically measured. Therefore , with
the one-path two-port calibration, the forward error terms are duplicated and used for both
forward and reverse measurements by manually reversing the test device .
Figure A -40. Full Two-P ort Error Model
The following equations show the full two-port error model equations for all four S-parameters
of a two-port device . Note that the mathematics for this comprehensive model use all forward
and reverse error terms and measured values . Thus , to perform full error correction for any
one parameter , all four S-parameters must be measured.
A-56 Basic Measurement Theory