Specifications And Regulations Compliance; Definition Of Terms - Keysight N77 Series N7711A User Manual

Keysight N77xx Series
User's Guide
3
Specifications and Regulations
Compliance

Definition of Terms

(Applicable) fiber type
Connection type for which the specifications and characteristics apply
(if not differently stated).
Absolute wavelength (frequency) accuracy
The maximum difference between the displayed wavelength
(frequency) and the actual wavelength (frequency) of the tunable laser
source. Wavelength is defined as wavelength in vacuum.
Constant operating conditions
This generally includes constant values of temperature, humidity,
wavelength, input power level, polarization state and mode
distribution, if the quantity is not explicitly subject to variation.
Linewidth
The 3 dB width of the optical spectrum, expressed in Hertz.
Conditions: SBS suppression off.
Measurement:
Using a self-heterodyning technique: The output of the laser under test
is sent through a Mach-Zehnder interferometer in which the length
difference of the two arms is longer than the coherence length of the
laser. The electrical noise spectrum of the photodetector current is
measured with Keysight lightwave signal analyzer, and the linewidth is
calculated from the heterodyne spectrum.
Alternatively, Using a heterodyning technique: The output of the laser
under test is mixed with another laser of the same type on a wide
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