Agilent Technologies 8719D, User Manual

Page: 425 / 673

Mixer Parameters That Can Measure
Figure 6-86. Mixer
Parameters
Transmission characteristics include conversion loss, conversion compression, group delay,
and RF feedthru.
n
Reflection
characteristics
include return loss, SWR and complex impedance.
n
Output power.
n
Other parameters of concern are isolation terms, including LO to RF isolation and LO to IF
isolation.
Accuracy Considerations
In mixer transmission measurements, you have RF and inputs and an IF output. Also
emanating from the IF port are several other mixing products of the RF and LO signals In
mixer reflection measurements, leakage signals from one mixer port propagate and appear
at the other two mixer ports. These unwanted mixing products or leakage signals can cause
distortion by mixing with a harmonic of the analyzer’s first down-conversion stage. ensure
that measurement accuracy is not degraded, you must certain frequencies or avoid them
by frequency selection. If you place attenuators at all mixer ports, you can reduce mismatch
uncertainties.