2-4
IM AQ1210-01EN
Sample Interval
The maximum number of sample data points is 256000. The shortest sample interval is determined by
the distance range.
Normal: The instrument uses the optimum sample interval for the measurement method to
perform measurements.
Hi-Resolution: The instrument uses a sample interval that would result in the greatest number of
data points.
If you use a short sample interval, you can measure for finer changes. However, the data size of the
measured result becomes large.
Attenuation
If large reflections are caused by connectors or by breaks in the optical fiber cable, the waveform may
be saturated. Specify attenuation to prevent the waveform from being saturated. The attenuations that
you can select vary depending on the pulse width, as shown in the following table.
Pulse Width (Example)
Selectable Attenuations
3 ns/5 ns
1
, 10 ns, 20 ns,
30 ns, 50 ns
0dB, 2.50dB, 5.00dB, 7.50dB, 10.00dB, 12.50dB, 15.00dB
100 ns, 200 ns, 300 ns,
500 ns, 1
µ
s
0dB, 2.50dB, 5.00dB, 7.50dB, 10.00dB, 12.50dB, 15.00dB, 17.50dB, 20.00dB
2
µ
s, 5
µ
s
0dB, 2.50dB, 5.00dB, 7.50dB, 10.00dB, 12.50dB, 15.00dB, 17.50dB, 20.00dB,
22.25dB, 25.00dB
10
µ
s, 20
µ
s
0dB, 2.50dB, 5.00dB, 7.50dB, 10.00dB, 12.50dB, 15.00dB, 17.50dB, 20.00dB,
22.25dB, 25.00dB, 27.50dB, 30.00dB
1 The pulse width is 5 ns on the AQ1210A/AQ1210E and 3 ns on the AQ1215A/AQ1215E/AQ1215F/
AQ1216F.
Average Method
Hi-Speed
In Hi-Speed mode, all sections are measured according to the specified attenuation. If the specified
attenuation value is not appropriate and a large reflection occurs, the waveform for that section may
be saturated.
If reflections are large, the waveform may saturate.
Hi-Reflection
In Hi-Reflection mode, the instrument can perform measurements correctly even if large reflections
(excluding extremely large reflections caused by sections of the fiber such as the open end of the
fiber) occur. In Hi-Reflection mode, the instrument sets the optimum attenuation according to the
backscatter level for each section, and performs the measurement. Therefore, the measurement
time is longer than in Hi-Speed mode.
The partitioning of the optical fiber into sections and the specifying of the optimum attenuation are
done automatically.
Note
Except when the optical fiber cable is short and there are no reflections, we recommend that you measure
with the average method be set to Hi-Reflection.
2.1 Measurement (Measure) Conditions