Anritsu MS9740B - Measuring Laser Diode Modules

5.6 Measuring Laser Diode Modules
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Measurement Functions
5.6 Measuring Laser Diode Modules
When using the laser diode module measurement function, the following
items are measured.
● Signal: Signal wavelength and signal level
Signal level varies according to the SignalLevel
settings made in the Signal Parameter dialog box.
● Peak: Peak signal wavelength and peak signal level
● Slice Level: This is the threshold value for calculating standard
deviation σ.
● SMSR: Side mode wavelength and level
● 2nd Peak: SMSR (Side Mode Suppression Ratio)
● Mode Offset: Difference between side mode wavelength and peak
wavelength (Mode Offset)
● SNR (Res **nm): Signal to noise ratio (actual measured value)
The measured noise level is used to calculate SNR.
● SNR (/*.*nm): SNR (Conversion value per Noise Span)
Uses noise level per noise bandwidth in SNR
calculation
● σ: Standard deviation of spectrum using RMS method
● Kσ: Spectrum width
K = 2.35 is equivalent to 3 dB down and K = 6.07 is
equivalent to 20 dB down.
● ndB Width: Spectrum width at specified cut level
● Stop Band: Difference between peak wavelength and both side
mode wavelengths
● Center Offset: Difference between peak wavelength and average of
both side mode wavelengths