Agilent Technologies E4428C, User Manual

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288 Chapter 9
BERT
Bit Error Rate Tester–Option UN7
Bit Error Rate Tester–Option UN7
The bit error rate test (BERT) capability allows you to perform bit error rate (BER) analysis on digital
communications equipment. This enables functional and parametric testing of receivers and components
including sensitivity and selectivity.
Block Diagram
When measuring BER, a clock signal that corresponds to the unit under test (UUT) output data must be
input to the BER CLK IN connector. If the clock is not available from the UUT, use the DATA CLK OUT
signal from the ESG baseband modulator.
Figure 9-18
Clock Gate Function
When you use the clock gate function, the clock signal to the BER CLK IN connector is valid only when the
clock gate signal to the BER GATE IN connector is ON.
Press the
Clock Gate Off On
softkey to toggle the clock gate function off and on.The
Clock Gate Polarity Neg Pos
softkey sets the input polarity of the clock gate signal supplied to the rear panel BER GATE IN connector.
When you select
Pos
(positive), the clock signal is valid when the clock gate signal is high; when you select
Neg
(negative), the clock signal is valid when the clock gate signal is low.