The adoption of Centralized Radio Access Network (C-RAN) architectures requires fronthaul systems capable of carrying large volumes of radio data while meeting stringent delay and jitter requirements. Ethernet Passive Optical Networks (EPONs) have emerged as a promising fronthaul solution due to their cost efficiency and compatibility with existing infrastructure. However, the traditional registration process for EPON systems halts the ongoing data transmissions during the registration period, thereby violating the enhanced Common Public Radio Interface (eCPRI) delay and jitter requirements. This limitation has been acknowledged by the ITU-T, which recommends the use of a dedicated wavelength channel for registration, leading to inefficient bandwidth utilization. In this paper, we propose a novel scheduling framework for a Time and Wavelength Division Multiplexed (TWDM) EPON-based fronthaul that enables periodic registration without wasting an additional wavelength channel. Performance evaluation demonstrates that the proposed method achieves up to a 71\% increase in the number of Radio Units (RUs) supported for a given number of wavelength channels, compared to a baseline scheme employing a dedicated registration wavelength.

翻译：集中式无线接入网（C-RAN）架构的采用要求前传系统能够承载大量无线数据，同时满足严格的时延和抖动要求。以太网无源光网络（EPON）因其成本效益高且与现有基础设施兼容，已成为一种有前景的前传解决方案。然而，EPON系统的传统注册过程会在注册期间中断正在进行的数据传输，从而违反增强型通用公共无线电接口（eCPRI）的时延和抖动要求。这一局限性已得到国际电信联盟电信标准化部门（ITU-T）的确认，其建议使用专用波长信道进行注册，但这会导致带宽利用率低下。本文提出了一种基于时分波分复用（TWDM）EPON前传的新型调度框架，该框架能够实现周期性注册而无需浪费额外的波长信道。性能评估表明，与采用专用注册波长的基准方案相比，所提方法在给定波长信道数的情况下，支持的无线单元（RU）数量最高可增加71%。