User`s guide

Definition of Terms Specifications
Agilent 81689A, 81689B and 81649A Tunable Laser Modules User’s Guide, Third Edition 39
Return Loss
The ratio of optical power incident to the TLS output port, at the TLS's
own wavelength, to the power reflected from the TLS output port.
Conditions: TLS disabled.
Sidemode Suppression Ratio
The ratio of average signal power to the optical power of the highest
sidemode within a distance from 0.1 to 6 GHz to the signal's optical
frequency, expressed in dB.
Conditions: at a specified output power and wavelength range,
temperature within operating temperature range, coherence control
off.
Measurement with the Agilent Lightwave Signal Analyzer, by
analyzing the heterodyning between the main signal and the highest
sidemode.
Signal-to-Source Spontaneous Emission
(SSE) Ratio
The ratio of signal power to maximum spontaneous emission power in
1 nanometer bandwidth within a ±3 nm window around the signal
wavelength, where ±1 nm around the signal wavelength are excluded,
at the specified output power, expressed in dB/nm.
Conditions: output power set to specified values, at temperatures
within operating temperature range, coherence control off.
Measurement with optical spectrum analyzer (OSA) at 0.5 nm
resolution bandwidth (to address the possibility of higher SSE within
a narrower bandwidth), then extrapolated to 1 nm bandwidth. On
low-SSE output (if applicable), with fiber Bragg grating inserted
between the TLS and the OSA in order to suppress the signal, thereby
enhancing the dynamic range of the OSA.
NOTE The specified signal-to-SSE ratio is also applicable to output powers
higher than the specified values.
Wavelength Range
The range of wavelengths for which the specifications apply.