Agilent Technologies 8753ET User Manual page 385

Device Measurement
Now the unknown is measured to obtain a value for the measured response, S
frequency. Refer to Figure
Figure 7-33 Measured S
This is the one-port error model equation solved for S
are now known for each test frequency, S
(
S
11M
S = ----------------------------------------------------------------- -
11 A
(
E S –
SF 11M
For reflection measurements on two-port devices, the same technique can be applied, but
the test device output port must be terminated in the system characteristic impedance.
This termination should have as low a reflection coefficient as the load used to determine
directivity. The additional reflection error caused by an improper termination at the test
device's output port is not incorporated into the one-port error model.
7-33.
11
11A
)
– E
DF
)
+ E
E
RF
DF
. Since the three errors and S
11A
can be computed as follows:
Operating Concepts
Measurement Calibration
, at each
11M
11M
7-47