Comcast LT1550-E, Инструкция по эксплуатации

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LT1550-E
www.comcast-sa.com
3.4.7 Frequency Adjust ITU in DWDM
To help DWDM applications, LT1550-E can adjust optical wavelength. The
adjustable range is ±100GHz, 50GHz stepping. The button on the front panel
or the Ethernet interface will complete the adjustment.
λ =c/f, c is the speed of light. It is the constant value.
c=299792458m/s, f is the frequency, its unit is Hz; eg frequency 193400GHZ,
the corresponding wavelength is 1550.12nm.
In the 1545-1560nm band, the frequency distance and the wavelength
distance is very similar to linear relationship.
50GHz frequency distance reflects to wavelength is very approximate to 0.4nm
width;
As the same, 100GHz frequency distance reflects to wavelength is very
approximate to 0.8nm width.
3.4.8 SBS Suppression Adjustment
SBS value is very important in 1550nm long-distance transmission system.
Stable continuous coherent light source, add +6 dBm optical power in the
standard single mode fiber may occur SBS phenomenon. Ultrahigh SBS
threshold will reduce CNR and CSO low-frequency indicators.
High SBS threshold will also influence self phase modulation (SPM) and reduce
high-frequency CSO indicator.
When meet the conditions, as far as possible to use a low threshold SBS.