光接入网高灵敏度低成本相干通信技术

光接入网高灵敏度低成本相干通信技术

唐明，李伟昊，冯振华

华中科技大学

摘要：于高性能通信多芯光纤（MCF），提出了一种波分空分混合复用光接入网（WSDM-OAN）架构，并采用MCF中间芯传输本征光、外层芯传输信号光的方式在下行传输（DS）中实现了空分自零差相干探测（SHCD）。相关实验表明，所提出的接入系统下行总传输速率可达4.8 Tbit/s，而且无需采用频偏补偿和相位恢复算法，并可采用10 MHz线宽的分布反馈（DFB）激光器。此外，提出了一种由单抽头复蝶形有限冲击响应（FIR）滤波器、4个N抽头实FIR滤波器和4×4 多输入多输出（MIMO）FIR滤波器构成的简化自适应均衡（AEQ）算法。相关实验表明，所提出的AEQ与2×2 MIMO结构AEQ性能相近，与4×4 MIMO结构AEQ相比功率代价小于1 dB。当滤波器抽头数25时，可降低59%的实数乘法数。
关键词：OAN；MCF；SHCD；AEQ

High-Sensitivity and Low-Cost Coherent Communication Technology for Optical Access Network

TANG Ming, LI Weihao, FENG Zhenhua

Huazhong University of Science and Technology

Abstract: A hybrid wavelength division and space division multiplexing optical access network (WSDM-OAN) based on high-performance communication multi-core fiber (MCF) is proposed in this paper. To realize the self-homodyne coherent detection (SHCD) in downstream (DS), the MCF inner cores transmit the local oscillator light, while the outer cores transmit the signal light. The related experiments show that the total transmission rate of the proposed system is up to 4.8 Tbit/s in DS, and carrier frequency offset compensation algorithms and phase recovering algorithms are need not to be used. The distributed feedback (DFB) lasers with 10 MHz linewidth can be adopted in this proposed system. A simplified adaptive equalization (AEQ) algorithm, which consists of a 1-tap complex-valued butterfly finite impulse response (B-FIR) filter, four N-tap real-valued FIR filters, and a 3-tap 4×4 multiple-input multiple-output (MIMO) FIR filter is also proposed. The experiment results show that the proposed AEQ share the same performance with 2×2 MIMO AEQ, and the power penalty is less than 1 dB compared with 4×4 MIMO AEQ. When using 25-tap filters, the number of real multipliers can be reduced by 59%.
Keywords: OAN；MCF；SHCD；AEQ