Abstract

Complex-valued double-sideband (CV-DSB) direct detection (DD) is a promising solution for high capacity and cost-sensitive data center interconnects, since it can reconstruct the optical field as a homodyne coherent receiver while does not require a costly local oscillator laser. In a carrier-assisted CV-DSB DD system, the carrier occupies a large proportion of the total optical signal power but bears no information. Reducing the carrier to signal power ratio (CSPR) can improve the information-bearing signal power and thus maximize the achievable system performance. Recently, we have proposed and demonstrated a deep-learning-enabled DD (DLEDD) scheme to reconstruct the full-field of the CV-DSB signal. In the DLEDD scheme, the optical CV-DSB signal was detected by a dispersion-diversity receiver and then recovered by a deep convolutional neural network (CNN). Nevertheless, the computational complexity of the deep CNN is the main obstacle to the application of the DLEDD scheme. In this paper, we demonstrate a 50-GBaud CV-DSB 32-ary quadrature amplitude modulation (32-QAM) signal transmission over 80-km single-mode fiber with ∼64% computational-budget reduction in the field reconstruction. This is achieved by using 1×1 convolutions to attain a sparse dimensionality (in particular the number of channels) of the deep CNN. To the best of our knowledge, we achieve the highest electrical spectral efficiency of 7.07 b/s/Hz per polarization per wavelength for a CV-DSB DD receiver without requiring a sharp-roll-off optical filter.

Deep-learning-enabled high-performance full-field direct detection with dispersion diversity

Xingfeng Li, Shaohua An, Honglin Ji, Jingchi Li, William Shieh, and Yikai Su
Opt. Express 30(7) 11767-11788 (2022)

Offset double sideband carrier assisted differential detection with field recovery at low carrier-to-signal power ratio

Peng Qin, Chenglin Bai, Zhiguo Wang, Hengying Xu, Lishan Yang, YiNing Zhang, Peiyun Ge, and Xueyuan Luo
Opt. Express 30(26) 48112-48132 (2022)

Carrier-assisted differential detection with reduced guard band and high electrical spectral efficiency

Jingchi Li, Shaohua An, Honglin Ji, Xingfeng Li, William Shieh, and Yikai Su
Opt. Express 29(21) 33502-33511 (2021)

Symmetric carrier assisted differential detection receiver with low-complexity signal-signal beating interference mitigation

Yixiao Zhu, Longsheng Li, Yan Fu, and Weisheng Hu
Opt. Express 28(13) 19008-19022 (2020)

Joint signal-to-signal beat interference mitigation for the field recovery of symmetric carrier-assisted differential detection with low carrier-to-signal power ratio

Zihua Huang, Jianping Li, Xinkuo Yu, Jianqing He, Jianbo Zhang, Kangping Zhong, and Yuwen Qin
Opt. Express 32(10) 18044-18054 (2024)