Anritsu MX183000A, Руководство по эксплуатации, Страница: 103 / 226

4.7 Jitter Tolerance Test Procedure
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per
ation
4.7.2 Measurement time
Repeat the process for measuring the bit error rate by changing the jitter
frequency and jitter amplitude.
MX183000A setups the jitter frequency, the waiting time after changing
the jitter amplitude, and the bit error rate measurement time under the
following names:
Waiting:
Waiting time after changing the jitter frequency
Settling: Waiting time after changing the jitter amplitude
Gating: Bit error rate measurement time
The time relationship in the Jitter Tolerance measurement is as shown
in the figure below:
Measurement time
Waiting Time
Settling Time
Gating Time
Frequency setup Frequency setup
Amplitude setup
Error measurement
Figure 4.7.2-1 Setup time relationship
4.7.3 Jitter Tolerance Estimate
The MX183000A allows BER to be estimated for high rates such as 1E–6
and for low rates such as 1E–20.
For example, the BER for E–20 cannot be measured practically, as the
error rate produces errors of 1 bit in 10
10
seconds (>317 years) even with
a 10 Gbit/s signal.
The distribution parameters
σ
and
µ
can be determined by measuring
the correlation with jitter modulation (SJ) for bitter error rate over a
particular range as shown in Figure 4.7.3-1. Jitter modulation estimate
curves for jitter modulation frequencies can be calculated for any
particular error rate using the equation in the distribution Figure
4.7.3-1.