Rohde & Schwarz SMBV100A, Руководство по эксплуатации

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Instrument Function
R&S
®
SMBV100A
190 Operating Manual 1176.8016.02 ─ 17
Terminated By
Displays the termination criterion for the measurement.
These criteria can be entered to keep the duration of the measurement short for low as
well as high bit error rates. The last measurement result is displayed after the mea-
surement has been terminated.
"User" The measurement was manually stopped with State > "Off" .
"Number of Data Bits"
The measurement stopped after the specified number of data bits
was reached.
"Number of Errors"
The measurement stopped after the specified number of errors was
reached.
Remote command:
:BERT:STATe
on page 542
:BERT:STOP
on page 543
State:
Displays the status of the measurement.
A green LED indicates a correct status, red denotes a faulty status.
The function displays the status of the data and clock lines, and of the synchronization.
It allows you to check if the measurement works properly. If the status is faulty, check
the BER signals at the connectors with an oscilloscope.
"Clock" The applied clock signal is detected.
"No Clock" The applied clock signal is not detected. Possible causes are:
●
The clock recovery is not available (e.g. with tests of RF compo-
nents).
If the signal is generated by the R&S
SMBV, the bit clock can be
extracted from the CLOCK output connector (only with "Custom
Dig Mod" signals in real time). If signals complying with other digi-
tal standards are generated, or if ARB waveforms are used, you
can use a marker signal as a clock. As the DUT causes a delay,
the ratio of clock-to-data transmission times must be considered
and checked with an oscilloscope if necessary.
●
The wrong impedance for the applied clock rate is selected.
●
The wrong threshold for the applied clock signal is selected.
"Data" The applied data signal was detected.
"No Data" The applied data signal is not detected.
Only clocked-in signals are detected. If the clock signal is missing,
data changes are also not detected.
If the data is not detected, although the clock signal is detected, it can
be caused by:
●
The signal from the DUT is missing.
●
The wrong impedance for the applied clock rate was selected.
●
The wrong threshold for the applied data signal was selected.
"Sync" The measurement is synchronized.
Bit and Block Error Rate Measurements