Rohde & Schwarz R&S UPP, User Manual

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Instrument Functions
R&S
®
UPP
451 User Manual 1411.1055.32 ─ 10
With 2-channel or multichannel measurements, the frequency on the other channels is
often the same as the frequency on the reference channel. In such cases, it is advisa-
ble to display a frequency-related measured value instead of the frequency in the mea-
surement window of the other channels.
Note: In two-channel analyzers, the "reference channel" is always "channel 1 ", in mul-
tichannel analyzers, the reference channel is "user-definable in the Analyzer Config
Panel ".
"Off" Frequency measurement is deactivated.
Note: For signals for which no zero crossing can be detected (e.g.
weak noise signals, pure DC signals or very low frequency AC sig-
nals), the frequency measurement can be switched off, which will
considerably reduce the total measurement time.
Note: For frequency measurements, the input signal – beginning in
the zero crossing – must be observed over one complete period, but
with at least 100 samples. For function measurements with an
extremely short measurement time (e.g. peak measurement 1 ms
interval), the frequency measurement should therefore be deactiva-
ted.
"Frequency" Frequency measurement is performed on all activated channels.
"Freq &
Phase" Only available for two-channel measuring mode or in a multichannel
analyzer.
Frequency measurement is performed on the reference channel; the
measurement windows of the other channels contain the phase of the
other channel referenced to the reference channel.
If a phase is shown as invalid, the frequencies of this channel and the
reference channel are different or one of the channels does not have
an input signal.
Note: This measuring mode should only be selected if the frequency
on the reference channel is identical with the frequency on at least
one other measurement channel.
Frequency, Phase and Group Delay Measurement