Opt Lett. 2023 May 1;48(9):2317-2320. doi: 10.1364/OL.482331.
We propose a digital-carrier Kramers-Kronig (DC-KK) scheme based high-speed multimode fiber short-reach optical interconnect system with fundamental mode transmission. After optimization of the parameters, including the roll-off factor of the root-raised-cosine (RRC) filter, and the guard interval (GI) between signal and carrier tone, as well as the carrier signal power ratio (CSPR), 200-Gb/s 32-quadrature amplitude modulation (32QAM) signal transmission over 12-km OM2 fiber has been experimentally demonstrated with a bit error ratio (BER) below the soft-decision forward error correction (SD-FEC) threshold of 4 × 10. To the best of our knowledge, this is the highest experimental record of single lambda bitrate-distance-product (SLBDP) achieved by direct-detection (DD)-based transmission over a standard multimode fiber (MMF). The proposed scheme has potential to improve the system performance without replacing massive deployed legacy MMFs for future large-capacity data center interconnects (DCIs).
我们提出了一种基于数字载波 Kramer-Kronig（DC-KK）方案的高速多模光纤短距光互连系统，采用基模传输。在优化了参数后，包括根升余弦（RRC）滤波器的滚降系数、信号和载波音调之间的保护间隔（GI）以及载波信号功率比（CSPR），我们在 12km 的 OM2 光纤上实现了 200Gb/s 的 32 正交幅度调制（32QAM）信号传输，误码率（BER）低于 4×10 的软判决前向纠错（SD-FEC）阈值。据我们所知，这是基于直接检测（DD）的标准多模光纤（MMF）传输实现的单个波长比特率-距离积（SLBDP）的最高实验记录。该方案有望在不更换大量部署的传统 MMF 的情况下提高系统性能，从而适用于未来的大容量数据中心互连（DCI）。
