Rohde & Schwarz SMBV100A - Bit and Block Error Rate Measurements; Test Setup

Instrument Function
R&S
®
SMBV100A
183Operating Manual 1176.8016.02 ─ 17
This signal is picked off at the output of the baseband main module ("Impairment" func-
tion block), i.e. contained in the displayed signal is:
●
impairment of the signal as defined by the user and the addition of noise.
The spectrum display of the output signal is particularly suitable for checking multi car-
rier signals.
5.4 Bit and Block Error Rate Measurements
The option R&S SMBV-K80 provides a BER ("Bit Error Rate") tester to evaluate the bit
error rate of a signal demodulated and decoded by a DUT. The instrument option also
includes a BLER ("BLock Error Rate") measurement, used to verify CRC checksums.
The ratio of errored blocks to total blocks yields the block error rate.
In addition, a test generator allows you to check if the BER and BLER measurements
work properly, see Chapter 5.4.13.2, "Test Generator Settings", on page 204.
5.4.1 Test Setup
The following figure shows the test setup for the bit/block error rate measurement. The
data for the DUT can be generated by the R&S SMBV, or a user-defined external
source. The R&S SMBV can also generate an externally computed modulation signal,
e.g. created with the R&S WinIQSIM2 software (see Chapter 5.9.4.2, "ARB User Inter-
face", on page 384).
For the bit error rate measurement, the R&S SMBV transmits a known PRBS (pseudo
random binary sequence) to the DUT. The DUT demodulates the received data
sequence, and returns the data and control signals as e.g. the clock signal, data
enable, etc. to the R&S SMBV. The BER function synchronizes to the sent PRBS
sequence and counts the bit errors. The resulting bit error rate is the quotient of the
number of error bits to the total number of bits.
Bit and Block Error Rate Measurements