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Specifications
Definition of Terms
Measurement: either with a fiber-loop type polarization controller
using the polarization scanning method, or with a wavelength type
polarization controller using the Mueller met hod.
Polarization mode dispersion
The change of transit time caused by changing the input
polarization state, expressed in fs (10-15 seconds).
Conditions: Generation of all polar ization states (covering the
entire Poincar sphere.
Measurement: with the Agilent Technologies polarization
analyzer.
Repeatability
The random uncertainty in reproducing the attenuation after
changing and re-setting the attenuation. The repeatability is ± half
the span between the maximum and the minimum attenuations,
expressed in dB.
Conditions: uninterrupted line voltage, constant wavelength
setting, temperature within ±1 K, constant input polarizatio n state.
Measurement: with an optical power meter.
Return loss
The ratio of the incident power to the reflected power, expressed in
dB.
Conditions: jumper cables with hi gh- quality connectors on both
attenuator ports. Arbitrary atten uati on setting. Applicable to both
attenuator ports, with the respective second port terminated (zero
reference).
Measurement: with a return loss meter, using a Fabry-Perot type
laser source. The measurement result includes attenuator-internal
reflectances and reflectances from both attenuator ports.
Wavelength range The range of wavelengths to which the
specifications apply.