NTT Communications Corp. has confirmed the commercial viability of digital coherent transmission, a next-generation optical transmission technology, following the successful trial of 100 Gb/s optical transmission on its PC-1 transpacific subsea cable system. The company has decided to incorporate the new technology into the PC-1 by the middle of 2013. The upgrade will boost the PC-1's transmission capacity to 10 Tb/s, more than triple its current capacity of 3.2 Tb/s. Digital coherent transmission improves spectral efficiency through multilevel modulation such as phase modulation and polarization multiplexing. It greatly enhances receiver sensitivity by combining coherent detection and digital signal processing, said the company. NTT Com is helping to meet the demand for data communication capacity with its PC-1 cable, which links Japan. The company uses the cable system to deliver global IP network, Arcstar Universal One cloud network and global cloud services. “Enhancing the capabilities of this PC-1, which provides the transpacific shortest link, through the most advanced technologies will satisfy ever-increasing traffic and will be extremely beneficial for users,” said Takahiro Sumimoto, CEO of PC Landing Corp. PC Landing Corp., an NTT Com company and operator of the PC-1, in October succeeded in a trial 100-Gb/s optical communication transmission using digital coherent technology. Conducted over more than 9500 km of PC-1 fiber, the trial was supported by the PC-1's optically optimized architecture, including efficiently placed optical repeaters and optical fiber layout, according to NTT Com. For more information, visit: www.ntt.com