Instrument Function
R&S
®
SMU200A
178Operating Manual 1007.9845.32 ─ 15
Fig. 5-2: The length of the signal is too short for a complete PRBS sequence; PRBS generation is
restarted by the Restart signal when the signal begins anew.
Frames generated by the R&S Signal Generator or the R&S WinIQSIM2 software contain
continuous PRBS data, i.e. the PRBS sequence is continuously written to the user data
fields. Consequently, if the R&S Signal Generator is used as a data source, a restart is
only necessary if (e.g. when using a waveform) the total length of the signal does not
equal a whole-number multiple of a PRBS sequence.
Fig. 5-3: TDMA signal generated by the R&S Signal Generator with user data that contains the PRBS
data sequence. The PRBS sequence is continuously written to the user data fields.
5.4.8 Data Enable
In the case of the bit error rate measurement, the data signals usually contain not only
PRBS data but also other data (e.g. sync and preambles, see figure) that would result in
bit errors. The BER measurement for this data can then be interrupted using the "Data
Enable"signal. The "Data Enable" signal is fed in at the BERT input.
Fig. 5-4: 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.
In the case of the block error rate measurement, the "Data Enable" signal masks the user
data (see following figure).
Bit and Block Error Rate Measurements - BERT Block
To Next Page
Loading...
