High-speed coherent WDM PON for next-generation access network

The wavelength-division-multiplexed passive optical network (WDM PON) is very attractive for the future broadband access network due to its capability of providing practically unlimited bandwidth to each subscriber. However, for the massive commercial deployment, its competitiveness is yet to be improved. In particular, we need to increase its operating speed and maximum reach, and, at the same time, enhance its cost-effectiveness. For these objectives, we have developed the high-speed WDM PON operating at per-wavelength speed of > 10 Gb/s by using reflective semiconductor optical amplifiers (RSOAs) and the digital coherent detection technique. We also evaluated the maximum operable speed of the RSOA-based WDM PON by using the classical Shannon theorem. This paper reviews these progresses achieved at KAIST.