R&S AFQ100A Operating Manual page 190

R&S AFQ100A
Note:
If the data is not enabled, the BER measurement is stopped completely. The identification circuit for
Pattern Ignore as well as the PRBS generator of the BER measurement wait as long as the data is
not enabled. If the data is enabled, the measurement is continued.
Example:
frame
access header
data
clock
data
enable
The figure shows a TDMA signal with user data that contains the PRBS data sequence and various
check fields which should be ignored for the bit error rate measurement. Below that are the associated
clock and Data Enable signals.
1401.3084.32
Bit Error Rate Measurements - BERT Block
user data
Any signal at the Data Enable input is ignored; all
Not Used
data at the BERT data input is used for the
measurement.
Remote-control command:
BERT:SET:DEN OFF
The Data Enable signal is used. The only data
Low
measured is the data at the BERT data input
during a low level of the Data Enable signal. The
measurement is interrupted during a high level of
the Data Enable signal.
Remote-control command:
BERT:SET:DEN LOW
The Data Enable signal is used. The only data
High
measured is the data at the BERT data input
during a high level of the Data Enable signal. The
measurement is interrupted during a low level of
the Data Enable signal.
Remote-control command:
BERT:SET:DEN HIGH
4.79
guard
E-3