Agilent Technologies 8753ET User Manual page 387

to return to the test device. A portion of this signal may be re-reflected at port 2, thus
affecting S , or part may be transmitted through the device in the reverse direction to
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appear at port 1, thus affecting S
phase of the transmitted signal to vary as a function of S
Figure 7-36.
Figure 7-36 Load Match E
The measured value, S
relationship between E
reflection coefficients of the test device must be measured and stored for use in the S
error-correction computation. Thus, the test setup is calibrated as described for reflection
to establish the directivity, E
E , terms for reflection measurements on both ports.
RF
Now that a calibrated port is available for reflection measurements, the thru is connected
and load match, E
LF
connection.
Transmission signal path frequency response is then measured with the thru connected.
The data is corrected for source and load match effects, then stored as transmission
frequency response, E
It is very important that the exact electrical length of the thru be known.
NOTE
Most calibration kits assume a zero length thru. For some connection types
such as Type-N, this implies one male and one female port. If the test system
requires a non-zero length thru, for example, one with two male test ports,
the exact electrical delay of the thru adapter must be used to modify the
built-in calibration kit definition of the thru.
. This error term, which causes the magnitude and
11M
LF
, consists of signal components that vary as a function of the
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and S as well as E
SF 11A
, source match, E
DF
, is determined by measuring the reflection coefficient of the thru
.
TF
, is called load match, E
22A
and S , so the input and output
LF 22A
, and reflection frequency response,
SF
Operating Concepts
Measurement Calibration
. See
LF
21A
7-49