R&S SMJ100A, Руководство по эксплуатации, Страница: 206 / 874

Instrument Function
R&S
®
SMJ100A
190 Operating Manual 1403.7458.32 ─ 14
This criterion terminates the measurement relatively quickly if the error rate is high.
The measurement result is statistically reliable, since many errors were already coun-
ted.
If the measurement is terminated because the number of bit errors entered here was
reached, Number of Errors appears to the right of Terminated By.
Remote command:
:BERT:SETup:MERRor
on page 517
PRBS
Selects the PRBS sequence. The data generated by the PRBS generator is used as a
reference for the measurement.
Note: Standard-compliant data inversion for PRBS15 and PRBS23 is performed auto-
matically when the PRBS is selected. "Data Polarity" remains unaffected.
Remote command:
:BERT:SETup:TYPE
on page 518
Data Polarity
Sets the polarity of the feedback data bits.
Note: Standard-compliant data inversion for PRBS15 and PRBS23 is performed auto-
matically when the PRBS is selected. "Data Polarity" remains unaffected.
"Norm"
High level stands for logic 1, low level for logic 0.
"Inv" Low level stands for logic 1, high level for logic 0.
Remote command:
:BERT:SETup:DATA[:POLarity]
on page 515
Clock Slope
Sets the polarity of the active slope of the feedback clock.
"Pos" The positive slope of the clock signal is active.
"Neg" The negative slope of the clock signal is active.
Remote command:
:BERT:SETup:CLOCk[:POLarity]
on page 514
Impedance
Sets the input impedance of the BERT inputs "Clock", "Data", "Data Enable" and
"Restart".
For high clock rates, 50 Ohms should be selected.
Remote command:
[:SOURce]:INPut:BERT:IMPedance
on page 520
Threshold
Sets high/low threshold in volts for the BERT inputs "Clock", "Data", "Data Enable" and
"Restart".
The variable threshold makes it possible to align the BERT interface with the level of
different input signals. In addition, reflections and other interference can be suppressed
by selecting the appropriate threshold.
Bit and Block Error Rate Measurements - BERT Block