OSN series including WDM equipment (OSN1800/3800/6800/8800/9800) and MSTP equipment(OSN500/550/580/3500/7500/7500II).
The DCM is used to compensate dispersion for optical signals. Each DCM has two fiber connectors to receive and send optical signals, which are connected to the optical interface of the corresponding board through optical fibers.In WDM systems, DCM is used to compensate for chromatic dispersion; DCU is used to compensate for chromatic dispersion in MSTP systems.
• For MSTP: The DCU can compensate for the dispersion for a maximum of two channels of optical signals. The DCU can be used with the BA and PA.
• For WDM: DCM modules are installed in DCM frames and are used to compensate for the positive dispersion of transmission fibers to help maintain the shape of a propagated signal.
After an optical signal is transmitted over a certain distance, the optical signal pulse expands because of the accumulation of positive dispersion. This pulse expansion has a negative impact on system transmission performance. Therefore, dispersion compensation modules (DCMs), which are passive devices, are required to compensate for the positive dispersion. DCMs use the inherent negative dispersion of a dispersion compensating fiber to offset the positive dispersion of transmission fibers to prevent pulse expansion.
Depending on the technology that DCMs use, two types of DCMs are available: dispersion compensating fiber (DCF)-DCMs and fiber Bragg grating (FBG)-DCMs.
These DCMs can compensate for the following transmission distances: 5 km, 10 km, 20 km, 40 km, 60 km, 80 km, 100 km, 120 km, 160 km, 200 km, and 240 km.
The DCM frame is used to hold the dispersion compensation module (DCM), and one DCM frame can hold up to two DCMs. The left- and right-side mounting ears attach the DCM frame to the columns of a cabinet.
Hope it help.
By the way, you can check the price of Huawei Transmission Network.
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