Yan An, Li Guoqiang, Xing Sizhe, Shen Wangwei, Hu Yongzhu, Sun Aolong, Shi Jianyang, Li Ziwei, Shen Chao, Chi Nan, Zhang Junwen
Opt Lett. 2024 Apr 1;49(7):1656-1659. doi: 10.1364/OL.517152.
The escalating surge in datacenter traffic creates a pressing demand for augmenting the capacity of cost-effective intensity modulation and direct detection (IM/DD) systems. In this Letter, we report the demonstration of the single-lane 128-GBaud probabilistically shaped (PS)-PAM-20 IM/DD transmission using only a single digital-to-analog converter (DAC) for a net 400 G/λ system. Based on the advanced digital signal processing (DSP), we achieve net bitrates of up to 437 Gb/s for optical back-to-back and 432 Gb/s after the 0.5-km SSMF transmission in the C-band with 128-Gbaud PS-PAM-20 signals. This work is the latest demonstration on ultra-high-order PS-PAM signals achieving net bitrates exceeding 400 Gb/s despite symbol rate limitations. Notably, to the best of our knowledge, the realized net information rate ([net bitrate]/[symbol rate]) of 3.37 marks a new achievement within the domain of 400 G/λ IM/DD systems, with promising implications for enhancing bandwidth efficiency in the upcoming 1.6-Tb Ethernet scenario.
数据中心流量的不断激增，对提高具有成本效益的强度调制和直接检测（IM/DD）系统的容量产生了迫切需求。在本信函中，我们报告了在净400 G/λ系统中，仅使用单个数模转换器（DAC）实现单通道128 GBaud概率整形（PS）-PAM-20 IM/DD传输的演示。基于先进的数字信号处理（DSP），我们在C波段使用128 GBaud PS-PAM-20信号进行光背靠背传输时实现了高达437 Gb/s的净比特率，在经过0.5 km单模光纤（SSMF）传输后实现了432 Gb/s的净比特率。这项工作是关于超高阶PS-PAM信号的最新演示，尽管存在符号率限制，但仍实现了超过400 Gb/s的净比特率。值得注意的是，据我们所知，在400 G/λ IM/DD系统领域中，实现的3.37的净信息率（[净比特率]/[符号率]）标志着一项新成就，对在即将到来的1.6 Tb以太网场景中提高带宽效率具有重要意义。
