Digital Coherent Technology for Optical Fiber and Radio-Over-fiber Transmission Systems

Current status and the future perspective of digital coherent technology for optical fiber and radio-over-fiber (RoF) transmission systems will be reviewed. For the starter, we will review two key digital coherent techniques; the coherent receiver and compensation techniques for the fiber nonlinearity-induced impairments. Next, we will present a commercial deployment of 100 G digital coherent long-haul optical fiber transmission system and the R&D challenge to 400 G and beyond transmission systems. Finally, we will turn our focus on digital coherent RoF transmission systems. We will introduce an ongoing government-funded R&D program in Japan, entitled "Agile deployment capability of highly resilient optical and radio seamless communication systems." It was initiated after the disaster in Japan in March 2011, aiming at optical fiber and millimeter-wave-band radio seamless transmission system. It would be a good use case of cutting-edge radio-over-fiber technology for an immediate social need.