设计一种基于腔内全光纤模式复用器/解复用器(MUX/DEMUX)的少模环形光纤激光器,实现了LP01模、LP11模、LP21模及混合模式可切换的激光输出。实验结果表明,利用低串扰的全光纤模式MUX/DEMUX结合4×1光开关,激光器可在三个最低阶的线偏振(LP)模式及其混合模式之间进行切换,LP01模、LP11模、LP21模的泵浦阈值分别为40、60、80 mW,斜率效率分别为1.2%、0.82%、0.56%。对设计的少模环形光纤激光器结构进行数值模拟和参数优化,极大地改善了波长偏移问题,实现了小于0.032 nm的3 dB线宽。

针对弹性光网络中不同粒度业务之间的服务公平性问题，提出了公平性感知的动态频谱分配算法.通过引入一个新的效用函数，使得进行频谱分配时不仅考虑不同粒度业务间的服务公平性，而且还兼顾网络整体的频谱资源利用率，从而大大缓解了网络整体阻塞性能损伤.仿真结果表明，在动态网络环境下，该方案可以极大地提高弹性光网络中不同粒度业务之间的服务公平性，并且没有明显的阻塞性能恶化.

Orthogonal frequency division multiplexing-passive optical network (OFDM-PON) and single-carrier frequency division multiplexing (SCFDM)-PON are promising solutions for future high-speed PON-based access. A polarization division multiplexing scheme with direct detection is proposed for OFDM-PON to effectively reduce bandwidth requirements for components. However, the scheme strictly requires spectrum overlapping of two orthogonal sidebands and the 4×4 multi-input-multi-output (MIMO) algorithm to eliminate complex cross-polarization interference. In this letter, we propose a polarization interleaving (PI) approach that significantly reduces bandwidth requirements for optical and electrical components while achieving a high-flexibility and low-complexity MIMO algorithm. Downstream single sideband PI-SCFDM transmission is experimentally demonstrated.

We demonstrate the long distance transmission of single-carrier frequency division multiple address signals by directly-modulated optically injection-locked vertical-cavity surface-emitting laser. Transmission distance as long as 50 km is achieved at 5 Gb/s (2.5 Gb/s for each user) through data pattern inversion and higher frequency response gain under optical injection locking.

Schemes integrating inter-carrier interference (ICI) self-cancellation and common phase error (CPE) compensation for coherent optical orthogonal frequency division multiplexing (CO-OFDM) systems are investigated. The purpose of our research is to counteract the impacts of laser phase noise and fiber nonlinearity. We propose two ICI self-cancellation-based CO-OFDM schemes, and adopt a pilot-aided decision feedback (DFB) loop for CPE compensation. The proposed schemes are compared with conventional CO-OFDM schemes at the same spectral efficiency. Simulations show that our schemes can not only enhance laser linewidth tolerance of the CO-OFDM system, but also present strong robustness against fiber nonlinearity.