相比于传统的强度调制/直接检测（IM/DD）系统，相干系统具有更高的容量和功率预算，能更好地满足高容量无源光网络（PON）的需求。近年来，如何将相干应用于PON场景以更好地支撑未来高带宽业务已成为研究热点。文章从系统架构、相干简化、上行突发模式检测以及灵活PON 4个方面对相干PON关键技术研究现状进行了总结，并展望提出了激光共享上下行滤波器组多载波（FBMC）-PON和半导体光放大器（SOA）电流调控灵活PON方案。

Compared to the traditional Intensity Modulation and Direct Detection (IM/DD) system, the coherent system offers higher capacity and power budget, better meeting the needs of high-capacity Passive Optical Network (PON). In recent years, the application of coherent technology in PON to better support future high-bandwidth services has become a hot research topic. This article summarizes the research progress in coherent PON technology from four aspects: system architecture, coherent simplification, uplink burst-mode detection, and flexible PON. In addition, it proposes laser-shared uplink and downlink Filter Bank Multi-Carrier (FBMC)-PON and Semiconductor Optical Amplifier (SOA) current-adjusted flexible PON schemes.