User`s guide

Chapter 8 317
Frequency-Offset Measurement (Option 008)
Measurement of Mixers
8. Frequency Offset
Measurement
(Option 008)
for each port. The use of the Multiplier/Divisor/Offset key is recommended as a rule. In
this way, the offset value is automatically retained even if you have changed the setting
range of the basic frequency, since the correlation of the frequencies among ports is
defined as a formula. Using
Start/Stop key will set M and O, which can be determined
from the specified frequency and the normal frequency, while maintaining the preset D.
Procedures for enabling frequency-offset function
Follow the steps below to enable the frequency-offset function.
Step 1. Press (or ) to activate the channel on which the frequency-offset
is to be set.
Step 2. Press -
Frequency Offset to display “Frequency Offset Menu.”
Step 3. Press
Frequency Offset to enable the frequency-offset function (ON).
NOTE Keep in mind the following when you turn ON the frequency-offset function:
•If
Swept is selected for the Sweep Mode, it will be changed to Stepped (from Std
Swept
to Std Stepped, and from Fast Swept to Fast Stepped).
• The phase information of the measurement value becomes meaningless. Therefore, the
view of
Phase, Group Delay, Smith, Polar, Real, Imaginary, Expand Phase or
Positive Phase specified with the key has no actual meaning. In addition, any
other function in the
Conversion menu of the key that cannot be calculated
without phase information, including the parameter conversion function, will not
operate correctly.
•
Fixture Simulator and Time Domain (Transform, Gating) are changed to OFF.
• If the measured frequency exceeds the measurable range (300 kHz to 3 GHz, or 8.5
GHz), an error will occur during the measurement.
Step 4. Once the frequency-offset function is enabled, the frequencies (Figure 8-2) set at each port
are displayed for each measured trace in the lower part of the screen.
Figure 8-2 Frequency-offset sweep
NOTE If the frequency-offset function is turned ON, the number of sweeps during measurement
will increase. For example, you can use two sweeps to measure the S-parameters of a
2-port setup in a normal frequency sweep; however, four sweeps are needed when the
frequency-offset function is turned
ON. This holds true regardless of whether the ports
have the same frequency setting.