浙江大学现代光学仪器国家重点实验室光及电磁波研究中心, 浙江 杭州 310058
基于支持向量机(SVM)的机器学习方法提出了空间激光通信四进制脉冲振幅调制(PAM-4)信号的检测算法。利用功率谱密度反演方法仿真大气相位屏,结合Taylor冰冻流假设,得到了激光载波经过大气湍流信道的光场信号,叠加接收端高斯白噪声后,采用SVM检测算法针对所得的PAM-4信号进行判决。SVM检测算法与大气信道无关。SVM检测算法对接收信号数据进行分组,对各组数据进行交叉验证并完成学习,并对参数进行调整。通过多次二分类确定各电平之间的最优超平面。最后,SVM作出信号判决。SVM检测算法得到的误码率低于双步盲检测法,在大气湍流较弱的情况下与最优边界检测法的结果相当,说明SVM检测算法具有良好的性能。
大气光学 空间激光通信 支持向量机 大气湍流 谱密度反演法 光学学报
2018, 38(11): 1101002
Author Affiliations
Abstract
Centre for Optical and Electromagnetic Research, State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310058, China
All-optical two-channel format conversion is proposed and experimentally demonstrated from a 40 Gbit/s polarization multiplexing (Pol-MUX) non-return-to-zero quadrature phase-shift keying (QPSK) signal to Pol-MUX binary phase-shift keying (BPSK) signals by using phase-doubled four-wave mixing effects with two polarization-angled pumps in a silicon waveguide. The eye diagrams and constellation diagrams of the original QPSK sequences and the converted BPSK sequences of each channel are clearly observed on the two polarization states. Moreover, the bit error rates (BERs) of the two converted idlers are measured. The power penalties of all these converted BPSK sequences on both X and Y polarization states are less than 3.4 dB at a BER of 3.8 × 10?3.(20130101110089); Natural Science Foundation of Zhejiang Province (LY14F050006).
Phase modulation Phase modulation Nonlinear optical signal processing Nonlinear optical signal processing Nonlinear optics Nonlinear optics four-wave mixing four-wave mixing Nonlinear optics Nonlinear optics integrated optics integrated optics Photonics Research
2016, 4(6): 06000245
1 浙江大学光及电磁波研究中心， 浙江 杭州 310058
2 浙江师范大学浙江大学光学联合研究实验室， 浙江 杭州 310058
3 浙江师范大学信息光学研究所， 浙江 金华 321004
提出并实现了一种以高非线性色散位移光纤为增益介质，以光栅对形成谐振腔，简单线形结构的连续光抽运的波长间隔可调谐多波长光纤光学参量振荡器(MW-FOPO)。采用波长可调谐的窄线宽激光器作为抽运种子光源，以伪随机相位调制抽运光来抑制高非线性光纤中的受激布里渊（SBS）散射效应，结合高功率掺铒光纤放大器构成光纤光学参量振荡器的大功率抽运，通过四波混频（FWM）效应获得了室温下稳定的多波长激光输出。MW-FOPO的波长间隔可以通过调节抽运波长进行调谐。在1505~1615 nm光谱范围内，获得了17条消光比大于10 dB的多波长谱线。实验证明了MW-FOPO实现多波长激光光源的优异特性。
光纤光学 参量振荡器 四波混频 高非线性光纤 光纤激光器 受激布里渊散射
Author Affiliations
Abstract
Centre for Optical and Electromagnetic Research, State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310058
A multi-wavelength erbium-doped fiber laser (MEDFL) with simple line structure is experimentally demonstrated by using a Sagnac interferometer as a comb filter. It is shown that the multi-wavelength lasing is quite stable at room temperature due to the four-wave mixing (FWM) effect among different laser channels in the dispersion-shifted fiber cooperated in the laser cavity.
光纤激光器 四波混频 Sagnac环形滤波器 掺铒光纤 140.3510 Lasers, fiber 190.4380 Nonlinear optics, four-wave mixing 120.5790 Sagnac effect 060.2410 Fibers, erbium Chinese Optics Letters
2007, 5(9): 519
