9 Convergence and upgrade of optical networks
9.1 Convergence and upgrade of optical networks

Demand for higher information capacity and bit rates require upgrading existing optical systems or running more systems on one fibre. Coexistence of optical systems refers to CWDM and DWDM networks sharing the passive optical infrastructure.

DWDM over CWDM

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Sample solution for DWDM over CWDM system – optical channels.

Hybrid solutions

Hybrid DWDM 10G/40G

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Optical spectrum of DWDM with channel interleaving.

Hybrid DWDM 10G/40G with safety band

Spectral split of 10G and 40G by safety band can help reducing the cross phase modulation from the 10G system.

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Safety band (100 GHz) splitting two systems (RZ-DQPSK and P-DPSK 40G channels).