YOKOGAWA AQ1215A - Page 15

1-9
IM AQ1210-01EN
Features
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2
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11
App
Index
Dynamic Range
Dynamic range refers to the range of optical power levels that can be measured. The larger the
dynamic range, the greater the distance that optical pulses can be measured over.
Measured waveform
Noise peak
2.6 dB
RMS level of noise
Dynamic range
(SNR=1)
Dead Zone
An area where the influence of a large event such as a connector’s connection point makes it
impossible to recognize other events that exist in that area is a dead zone. There are the following
types of dead zones.
Event Dead Zone
An area where adjacent reflections cannot be separated. This is the area represented by the pulse
width between the two points on the waveform at the level that is 1.5 dB below the peak value.
Attenuation Dead Zone
An area where, because there is a large reflection, the surrounding splice losses cannot be
measured.
Event dead zone
Attenuation dead zone
1.5 dB
• Near-end Dead Zone Prevention
In sections where near-end reflection is detected, loss and reflections that occur at connections
cannot be detected. If you are measuring a short distance, connect a launch fiber cable to move
events that are hidden in the near-end reflection the distance of the launch fiber cable.
Do not bend the optical fiber cable.
Optical fiber cable
being measured
Launch fiber
Event generation
point
Small reflection that was hidden
within a large reflection
AQ1210A, AQ1215A,
AQ1210E, AQ1215E,
AQ1215F, AQ1216F
1.3 Displaying Measured Data (OTDR)