Erbium Doped Fiber (Pumped) - Agilent Technologies 86038B User Manual

Erbium Doped Fiber (Pumped)

Agilent 86038B Photonic Dispersion and Loss Analyzer, Second Edition
Measurement Tips
• The high loss of this device degrades the signal to noise,
making it necessary to combat the noise with various setup
conditions. For best signal to noise, select 2000 MHz
modulation frequency.
• Improve signal to noise by using a narrower IF bandwidth (70
Hz or even 30 Hz) and a larger number of samples.
• Reduce trace noise by means of the built-in smoothing
functions.
• Swept mode gathers a large number of points to smooth,
taking advantage of the smoothing function. However, the
step mode allows taking and averaging a large number of
samples at each wavelength, also reducing the noise. Try
both modes to find the best trade-off of accuracy and
measurement speed.
Characteristics
• High gain (20 to 30 dB)
• High power output (>20 dBm)
• Amplified spontaneous emission (ASE) 'noise'
• Often a broadband device
• Low dispersion (very slight change in group delay over
wavelength)
• PMD is usually specified and may come from isolator
Measurement Tips
• Insert attenuation following the EDFA to avoid overdriving
the input of the 86038B. Refer to
for input power limitations.
• Improve signal to noise by using a narrower IF bandwidth (70
Hz or even 30 Hz). To get even a lower noise, the number of
samples can also be increased.
• Reduce trace noise by means of the built-in smoothing
functions.
"Conditions" on page 342
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