Coherent all-optical reservoir computing for nonlinear equalization in long-haul optical fiber communication systems

• Published in: Optics and laser technology Vol. 174; p. 110697
• Main Authors: Peng, Guanju, Liu, Yaping, Li, Zheng, Zhu, Kunpeng, Yang, Zhiqun, Li, Jianping, Zhang, Shigui, Huang, Zhanhua, Zhang, Lin
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2024
• Subjects: Long-haul transmission; Nonlinear equalization; Nonlinearity mitigation; Optical fiber communication; Photonic reservoir computing; Photonic reservoir computing; Long-haul transmission; Nonlinearity mitigation; Optical fiber communication; Nonlinear equalization
• ISSN: 0030-3992; 1879-2545
• DOI: 10.1016/j.optlastec.2024.110697

•A reservoir computing (RC) is operated optically without O/E/O conversion.•The all-optical RC mitigates nonlinear distortion in a 3960-km fiber link.•Phase property enhances the RC’s performance in nonlinear signal processing.•The RC improves the Q2 factor by 2.6 dB in a single-λ system and 1.9 dB in a WDM system. Photonic reservoir computing (RC), as a promising paradigm of optical signal processing, has attracted a great deal of attention in fiber nonlinearity equalization recently. For real long-haul transmission scenarios, we propose an all-optical RC operated in a coherent scheme to mitigate the nonlinear distortion of high-speed signals. Compared with the direct decision architecture, the proposed RC can dramatically improve the Q2 factor by 2.6 dB for a single-wavelength system and 1.9 dB for a 7-channel wavelength-division multiplexing (WDM) system over 3960-km fiber transmission. Furthermore, the robustness of the coherent all-optical RC is also verified by conducting studies on different training sequences. The coherent all-optical RC shows great potential in real-time nonlinearity mitigation for long-haul fiber transmissions.