BIG DATA

Successful lab tests prove viability of new modulation format that addresses unique needs of metro and regional networks

Enabling a 10-fold increase in system capacity over existing metro DWDM (Dense Wavelength Division Multiplexing) systems utilizing traditional techniques, ADVA Optical Networking has developed a novel DPSK-3ASK (Differential Phase-Shift Keying, 3-level Amplitude-Shift Keying) modulation format for serial 100Gbit/s transmission over a single wavelength channel.

In its labs in Meiningen, Germany, ADVA Optical Networking engineers successfully demonstrated for the first time this new modulation scheme, which utilizes available 40Gbit/s components and facilitates operation on a standard ITU (International Telecommunication Union) channel grid.

Worldwide traffic demand continues to skyrocket. Operators are striving to increase the capacity of their DWDM networks and have been steadily migrating from 10Gbit/s to 40Gbit/s, with 100Gbit/s being the next logical step.

Existing serial 100Gbit/s proposals such as DP-QPSK (Dual-Polarization Quadrature Phase Shift Keying) have been optimized for (ultra-) long haul transmission. Their complexity, cost and power consumption make them less suitable for metro applications. Given the substantial challenge of achieving reasonable link distances at 100Gbit/s due to chromatic dispersion and polarization mode dispersion, most industry work on short distances to date has centered on multi-fiber and multi-lambda approaches. Standards bodies IEEE, ITU-T and OIF (Institute of Electrical and Electronics Engineers, ITU-Standardization sector and Optical Internetworking Forum) have all been working on 100Gbit/s standards, with the focus currently placed on the two extremes of transmission distance.

“Current industry standardization efforts have left a gap between 40km and 600km, which leaves a sizeable portion of the market unaddressed. Our solution targets exactly that sweet spot,” stated Dr. Christoph Glingener, chief technology officer (CTO) for ADVA Optical Networking. “In addition, this solution utilizes off-the-shelf componentry, which enables it to be implemented sooner and with minimal industry investment, lessening the burden on optical component companies in a difficult market environment.”

ADVA Optical Networking’s DPSK-3ASK solution is complementary to existing 10- and 40Gbit/s designs and fits in existing installed network architectures, making it easier to upgrade and operate. Its direct detection alleviates the need for power-consuming, high-speed digital signal processing as typically required for long-haul schemes. It is compatible with DWDM systems like the ADVA FSP 3000, and when coupled with optical amplification facilitates metro/regional transmission distances up to 600km.

“Lowering the cost per bit is a common theme in both metro and long-haul DWDM networks,” continued Glingener. “We have an extremely compact and power-efficient 40Gbit/s solution today. Now, many network operators have asked us to address the metro challenge with a customized 100Gbit/s solution, which is what we’ve done. This DPSK-3ASK demonstration is an important milestone in the industry’s journey to realize 100Gbit/s.”

This work by ADVA Optical Networking was partially funded by the German Ministry of Education and Research (BMBF) and is part of the CELTIC 100GET-METRO project. Get more information on ADVA Optical Networking’s participation in this project.