An approach to generate high-speed and wideband frequency shift keying(FSK)signals based on carrier phase-shifted double sideband(CPS-DSB)modulation is proposed and experimentally validated.The core part of the scheme...An approach to generate high-speed and wideband frequency shift keying(FSK)signals based on carrier phase-shifted double sideband(CPS-DSB)modulation is proposed and experimentally validated.The core part of the scheme is a pair of cascaded polarization-sensitive LiNbO_(3) Mach–Zehnder modulators and phase modulators,whose polarization directions of the principal axes are mutually orthogonal to each other.A proof-of-concept experiment is carried out,where a 0.5 Gb/s FSK signal with the carrier frequencies of 4 and 8 GHz and a 1 Gb/s FSK signal with the carrier frequencies of 8 and 16 GHz are generated successfully.展开更多
This paper presents a novel scheme to monolithically integrate an evanescently-coupled uni-travelling carrier photodiode with a planar short multimode waveguide structure and a large optical cavity electroabsorption m...This paper presents a novel scheme to monolithically integrate an evanescently-coupled uni-travelling carrier photodiode with a planar short multimode waveguide structure and a large optical cavity electroabsorption modulator based on a multimode waveguide structure. By simulation, both electroabsorption modulator and photodiode show excellent optical performances. The device can be fabricated with conventional photolithography, reactive ion etching, and chemical wet etching.展开更多
传统的通信信号调制识别方法容易出现过拟合或欠拟合等问题,导致识别结果误差率较高。为了降低误差率、提高准确率,提出基于改进蚁群算法的高速电力线载波(High-speed Power Line Carrier,HPLC)通信信号调制识别方法。先通过计算幅度谱...传统的通信信号调制识别方法容易出现过拟合或欠拟合等问题,导致识别结果误差率较高。为了降低误差率、提高准确率,提出基于改进蚁群算法的高速电力线载波(High-speed Power Line Carrier,HPLC)通信信号调制识别方法。先通过计算幅度谱密度最大值、相位绝对值的标准偏差、频率绝对值的标准偏差,提取通信信号的特征参数,然后基于改进蚁群算法构建信号调制识别模型,实现HPLC通信信号的调制识别。设计对比实验,实验结果证明该方法在对通信信号调制识别准确率的提升方面具有显著效果,更符合实际的数字信号识别需要。在实际应用中,该方法可以广泛应用于各种需要快速、准确识别通信信号的领域。展开更多
提出一种在欠采样条件下的经过混合结构设计的射频发射机线性化方法。该方法基于欠采样频率选择性的非线性模型来校正调制器产生的镜像干扰信号以及射频功率放大器的互调失真信号。实验结果表明LTE的70 MHz双载波信号在发射机采样速率从...提出一种在欠采样条件下的经过混合结构设计的射频发射机线性化方法。该方法基于欠采样频率选择性的非线性模型来校正调制器产生的镜像干扰信号以及射频功率放大器的互调失真信号。实验结果表明LTE的70 MHz双载波信号在发射机采样速率从491.52 Ms/s降低至122.88 Ms/s时使用该组合方法较之前方法有10 d B的归一化最小均方误差改善以及10 d B的邻道功率泄露比抑制改善。展开更多
基金supported by the National Natural Science Foundation of China(Nos.U2006217,61775015,61801017,and 61827818)。
文摘An approach to generate high-speed and wideband frequency shift keying(FSK)signals based on carrier phase-shifted double sideband(CPS-DSB)modulation is proposed and experimentally validated.The core part of the scheme is a pair of cascaded polarization-sensitive LiNbO_(3) Mach–Zehnder modulators and phase modulators,whose polarization directions of the principal axes are mutually orthogonal to each other.A proof-of-concept experiment is carried out,where a 0.5 Gb/s FSK signal with the carrier frequencies of 4 and 8 GHz and a 1 Gb/s FSK signal with the carrier frequencies of 8 and 16 GHz are generated successfully.
基金supported by the National Natural Science Foundation of China (Grant No 90401025)the National 973 project (Grant No 2006CB604901)
文摘This paper presents a novel scheme to monolithically integrate an evanescently-coupled uni-travelling carrier photodiode with a planar short multimode waveguide structure and a large optical cavity electroabsorption modulator based on a multimode waveguide structure. By simulation, both electroabsorption modulator and photodiode show excellent optical performances. The device can be fabricated with conventional photolithography, reactive ion etching, and chemical wet etching.
文摘传统的通信信号调制识别方法容易出现过拟合或欠拟合等问题,导致识别结果误差率较高。为了降低误差率、提高准确率,提出基于改进蚁群算法的高速电力线载波(High-speed Power Line Carrier,HPLC)通信信号调制识别方法。先通过计算幅度谱密度最大值、相位绝对值的标准偏差、频率绝对值的标准偏差,提取通信信号的特征参数,然后基于改进蚁群算法构建信号调制识别模型,实现HPLC通信信号的调制识别。设计对比实验,实验结果证明该方法在对通信信号调制识别准确率的提升方面具有显著效果,更符合实际的数字信号识别需要。在实际应用中,该方法可以广泛应用于各种需要快速、准确识别通信信号的领域。
文摘提出一种在欠采样条件下的经过混合结构设计的射频发射机线性化方法。该方法基于欠采样频率选择性的非线性模型来校正调制器产生的镜像干扰信号以及射频功率放大器的互调失真信号。实验结果表明LTE的70 MHz双载波信号在发射机采样速率从491.52 Ms/s降低至122.88 Ms/s时使用该组合方法较之前方法有10 d B的归一化最小均方误差改善以及10 d B的邻道功率泄露比抑制改善。
