Rohde & Schwarz SMBV100A, Руководство по эксплуатации

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Instrument Function
R&S
®
SMBV100A
187 Operating Manual 1176.8016.02 ─ 17
Figure 5-3: TDMA signal generated by the R&S SMBV 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 5-4 ) that would
result in bit errors. The BER measurement for this data can then be interrupted using
the "Data Enable"signal.
Figure 5-4: TDMA signal with user data that contains the PRBS data sequence and various check
fields which can 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
Figure 5-5 ).
Figure 5-5: Data enable signal with block error rate measurement.
5.4.9 Pattern Ignore
Bit sequences of 32 bits or more with only "1" or "0", which some mobile radio stand-
ards provide instead of frame data when faulty frames are detected, can also be exclu-
ded from the measurement using the "Pattern Ignore" function (see
Figure 5-6 ).
Bit and Block Error Rate Measurements