Abstract

To mitigate nonlinear distortions in multi-user analog radio over fiber (A-RoF) system, a nonlinear equalizer (NLE) which combines transfer learning (TL) and waveform regression-based artificial neural network (ANN) is proposed and validated experimentally in this research. Unlike traditional ANNs, waveform regression ANNs can be regarded as waveform training ANNs and avoid complex-value training. In this paper, we first analyze the modulation distortions that appear in multi-user RoF systems and then propose a waveform regression ANN-based nonlinear equalizer (ANN-NLE). Subsequently, we use TL to reduce training costs and increase the compatibility of the ANN-NLE. Finally, an A-RoF system with multicore fiber is adopted to verify the proposed approach. According to the simulation and experimental results, the bit error ratio (BER) of a multi-user signal is decreased to the threshold of 3.8 × 10⁻³, and the improved optical receiver sensitivity is greater than 1.5 dB. This proposed method could realize nonlinear equalization and display good compatibility with different systems.

Fiber nonlinearity-induced penalty reduction in CO-OFDM by ANN-based nonlinear equalization

Elias Giacoumidis, Son T. Le, Mohammad Ghanbarisabagh, Mary McCarthy, Ivan Aldaya, Sofien Mhatli, Mutsam A. Jarajreh, Paul A. Haigh, Nick J. Doran, Andrew D. Ellis, and Benjamin J. Eggleton
Opt. Lett. 40(21) 5113-5116 (2015)

112-Gb/s SSB 16-QAM signal transmission over 120-km SMF with direct detection using a MIMO-ANN nonlinear equalizer

Shaohua An, Qingming Zhu, Jingchi Li, Yuye Ling, and Yikai Su
Opt. Express 27(9) 12794-12805 (2019)

Nonlinearity mitigation in a fiber-wireless integrated system based on low-complexity autoencoder and BiLSTM-ANN equalizer

Xiang Liu, Jiao Zhang, Min Zhu, Weidong Tong, Zhigang Xin, Yunwu Wang, Mingzheng Lei, Bingchang Hua, Yuancheng Cai, Yucong Zou, and Jianjun Yu
Opt. Express 31(12) 20005-20018 (2023)

Nonlinear equalization based on pruned artificial neural networks for 112-Gb/s SSB-PAM4 transmission over 80-km SSMF

Zhiquan Wan, Jianqiang Li, Liang Shu, Ming Luo, Xiang Li, Songnian Fu, and Kun Xu
Opt. Express 26(8) 10631-10642 (2018)

Bit-based support vector machine nonlinear detector for millimeter-wave radio-over-fiber mobile fronthaul systems

Yue Cui, Min Zhang, Danshi Wang, Siming Liu, Ze Li, and Gee-Kung Chang
Opt. Express 25(21) 26186-26197 (2017)