R&S SMJ100A, Руководство по эксплуатации

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Instrument Function
R&S
®
SMJ100A
187 Operating Manual 1403.7458.32 ─ 14
Data Bits
Displays the current number of data bits checked.
Remote command:
:BERT:RESult?
on page 512
Errors
Displays the current number of occurred errors.
Remote command:
:BERT:RESult?
on page 512
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 measurement has been terminated.
"User" The measurement was manually terminated by the user switching the
state to off.
"Number of
Data Bits" The measurement was terminated because the specified number of
data bits was reached
"Number of
Errors" The measurement was terminated because the specified number of
errors was reached.
Remote command:
:BERT:STATe
on page 519
:BERT:STOP
on page 519
State
Displays the status of the measurement.
This enables the user to check whether the measurement functions. The status of the
data and clock lines and of synchronization is checked and displayed.
If a faulty status is displayed, the signals can be checked at the BERT interface using
an oscilloscope.
"Clock" The applied clock signal was detected.
"No Clock" The applied clock signal was not detected. Possible causes are:
●
Clock recovery is not available (e.g. with tests of RF compo-
nents).
If the signal is generated using the R&S
SMJ, the bit clock can be
extracted from the CLOCK output connector (only with "Custom
Dig Mod" signals in realtime). If signals complying with other digi-
tal standards are generated or if ARB waveforms are used, a
marker signal can be used as a clock. As the DUT causes a
delay, the ratio of clock-to-data travel times must always be taken
into account and checked with an oscilloscope if necessary.
●
The wrong impedance for the applied clock rate was selected
(see "Impedance" parameter).
●
The wrong threshold for the applied clock signal was selected
(see "Threshold").
Bit and Block Error Rate Measurements - BERT Block