Measurement
247
characteristics of the calibration mixer from the measurement result. You
can use the IF filter to select any required frequency conversion
component such as RF+LO, RF-LO, and LO-RF. The calibration mixer and
IF filter can be seen as a part of the test system setup, just like the
network analyzer and the test cable; they are connected at the same
location during the entire calibration or measurement.
• The frequency range must be equal to or greater than that of
the measured mixer. If you want to test multiple mixers with a
single setup, select a wide range of calibration mixers that can
cover all frequencies of the target test devices.
Characterizing Calibration Mixer (with IF filter)
In vector-mixer calibration, you must characterize the calibration mixer
with the IF filter. As shown in the following figure, connect the target mixer
(with IF filter) to the port of the network analyzer on which vector
calibration has been performed and then connect an OPEN, SHORT or
LOAD standard to the end of the IF filter to start reflection measurement.
The signals measured at the test port include the reflection signal from the
mixer's RF port, the IF signal (IF+) converted by the mixer and then
reflected by the IF filter, and the IF signal (IF-) passing through the IF filer
and then reflected by the calibration standard.
The characteristics of the calibration mixer can be described in a 1-port
error model, and each error item can be determined from Γ
O
, Γ
S
, and Γ
L
,
which are obtained in the reflection measurement of individual standards.
Characteristics evaluation of calibration mixer (with IF filter)
To Next Page
Loading...
Need help?
General
