NEC qualifies 20-fibre pair subsea cable systems: larger fibre counts coming

Created January 20, 2020
News and Business

NEC Corporation and its subsidiary OCC Corporation have completed full qualification of subsea repeaters and optical cable containing up to 20 fibre pairs (40 fibres). NEC notes that this is a 25% improvement in fibre count over 16 fibre pair systems it has previously built, and that the development allows cable owners worldwide to construct subsea telecom cables capable of the highest traffic capacity, while optimising the cost per bit of the wet plant.

NEC says it has achieved the 20 fibre pair milestone with only minor modifications to its proven repeater and cable designs. This was accomplished by optimising key repeater components, and by proving that its existing cable design could easily accommodate more fibres. The 20 fibre pair repeaters continue to use quadruple pump sharing technology, first introduced by NEC in 2010, for high optical and electrical efficiency.

OCC’s 20 fibre pair cable can be manufactured using a range of existing optical fibres, according to the needs of each new cable system. Furthermore, OCC has demonstrated to its customers that they can visually identify individual fibres using a combination of ring marking and conventional fibre colouring. This allows the potential number of fibres in a cable to be greatly expanded. Significantly, in OCC cable, the fibre’s transmission performance is completely unaffected, either by the fibre colouring or cabling processes.

“As global capacity demand continues to soar, NEC is committed to helping our customers scale up their networks in a cost-effective way,” said Takaaki Ogata, Executive Technical Manager of NEC’s Submarine Network Division. “Further significant increases in the fibre pair count of NEC’s wet plant are coming soon.”

Mass production of the newly-qualified NEC/OCC wet plant has started.

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This article was written
by John Williamson

John Williamson is a freelance telecommunications, IT and military communications journalist. He has also written for national and international media, and been a telecoms advisor to the World Bank.