Toward Extremely Advanced Transmission (EXAT) technology

If the rapid growth of global Internet traffic of over 30% per year will continue, the absolute shortage of transmission capacity will become obvious within 10~15 years. The continuous improvements of existing technology cannot solve this serious problem. A study group named Extremely Advanced Transmission (EXAT) Initiative was organized in 2008 sponsored by NICT. Its report surveyed the technologies that will drastically advance the optical communication infrastructure, including (1) new optical fiber transmission line technology; (2) multiplexing and optical node technologies; (3) optical submarine cable technology. We are especially emphasizing the three “M” technologies: multi-core fiber, multi-level modulation format, and multi-mode control. The researchers at NICT are paying efforts as precursory trials, such as the evaluation of fiber fuse phenomena. In order to realize such fundamentally new approaches, close collaboration among telecommunication carriers, manufacturers and academia, both domestic and international, are indispensable. Our trials in Japan are briefly sketched.