Symptom
WDM equipment adopts mainly the NRZ, CRZ, DRZ, and ODB code patterns.
Does a code pattern indicate whether a board with this code pattern supports wavelength-tunable or not? Can two boards with different code patterns be interconnected?
Cause analysis
The mapping relationship between code patterns and the wavelength-tunable feature are as follows:
- The DRZ and ODB code patterns are not applicable to a a board with fixed wavelength, but a board with tunable wavelengths.
- The CRZ code pattern is applicable only to a board with fixed wavelength.
- The DRZ code pattern is applicable to either a board with fixed wavelength or a board with tunable wavelengths.
Interconnections of boards with different code patterns are as follows:
- Currently a board of the ODB code pattern cannot be interconnected directly with a board of the DRZ code pattern.
- An OTU board with the DRZ code pattern can be interconnected with one with the CRZ or NRZ code pattern; an OTU board with the ODB code pattern can be interconnected with one with the CRZ or NRZ code pattern; an OTU board with the CRZ code pattern can be interconnected with one with the NRZ code pattern. The WDM module at the transmit end on the WDM side, however, is different from that of common DWDM system. No special process is required at the receive end, because the WDM module at the receive end on the WDM side is same as that of common DWDM system.
