A full-duplex optical fiber/wireless single-channel coherent communication system is presented for high-speed data center interconnections. In-phase and quadrature modulator (IQM)-based dual polarization 256 quadrature amplitude modulation (DP-256-QAM) is implemented to achieve a maximum data rate of 640 Gbps with 40 Gbaud symbol rate for both the single-mode fiber (SMF) and free-space optics (FSO) links. Advanced digital signal processing (DSP) algorithms have been implemented at the receiver to compensate for signal impairments during propagation. The system with optical IQM and DSP algorithms can be fabricated in the form of cost-efficient integrated circuits and possess a potential spectral efficiency of 15.2344 b/s/Hz. A maximum transmission distance of 160 km and 4 km is achieved in simulation platform for the SMF and FSO links, respectively. The system performance is evaluated regarding laser linewidth requirements, optical signal-to-noise ratio tolerance, receiver sensitivity and launched optical power. This transceiver system shall be useful in high-speed long-haul communications, and the FSO system provides the same data rate to the remote areas, and last mile connections where laying of an optical fiber is not possible or cost is a major concern.

中文翻译：

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使用基于IQM的DP-256-QAM和DSP技术的640-Gbps，15.2344-b / s / Hz全双工光纤/无线单通道相干通信系统

提出了一种用于高速数据中心互连的全双工光纤/无线单通道相干通信系统。实施基于同相和正交调制器（IQM）的双偏振256正交幅度调制（DP-256-QAM），以实现单模光纤（SMF）的最大数据速率为640 Gbps，符号速率为40 Gbaud和自由空间光学（FSO）链接。先进的数字信号处理（DSP）算法已在接收器处实现，以补偿传播期间的信号损伤。具有光学IQM和DSP算法的系统可以以经济高效的集成电路形式制造，并具有15.2344 b / s / Hz的潜在频谱效率。在SMF和FSO链路的仿真平台中，最大传输距离分别达到160 km和4 km。根据激光器的线宽要求，光信噪比容差，接收器灵敏度和发射光功率来评估系统性能。该收发器系统将在高速长距离通信中有用，并且FSO系统向偏远地区提供相同的数据速率，并且在最后一英里的连接中无法铺设光纤或成本是主要问题。