排序方式: 共有64条查询结果,搜索用时 0 毫秒
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首次提出了利用单个波长实现光矢量调制技术的方法。在提出的方案中,通过直接控制双驱动马赫曾德尔调制器( DD-MZM )的射频驱动电压初始相位来获得正交条件,并在接受机端用一个纠正电路对接收信号进行调整。这种调制方式由于仅采用一个波长,不仅提高了光载波的频谱利用率,而且使正交条件不受光纤长度的影响,从而增加了整个系统的灵活性。仿真结果论证了QPSK和16-QAM两种调制格式下速率分别为2Gbit/s和4Gbit/s的42GHz毫米波信号生成。 相似文献
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RoF技术分析及其应用 总被引:3,自引:0,他引:3
介绍并分析了光纤承载射频(RoF)中的一些关键技术的解决方案,包括基于光纤光栅的单边带调制技术、自适应数字预失真系统和基于波长交叉的波分复用技术.此外,还介绍了RoF技术在4G无线接入网、路途车辆通信系统和室内信号覆盖系统中的应用和发展趋势. 相似文献
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Xiang Wang Xiao-Dong Zeng Zhe-Jun Feng Zhao-Jin Fan Ting Wang 《Journal of Modern Optics》2017,64(20):2157-2164
A millimetre wave (mm-wave) system based on forward modulation and novel double-sideband modulation (DSB) technique is proposed in radio over fibre. In this work, we describe and analyse a system capable of producing a high-quality 60-GHz mm-wave. In this system, the DSB consists of two Mach–Zehnder modulations, operates based on double-sideband modulation and achieves second-order suppression modulation. The principle of the photoelectric system is analysed and simulated. The mm-wave signal has low-phase noise and error rate, and the performance of the whole system has been improved. 相似文献
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In order to satisfy the increasing demand of wireless broadband multimedia services, much attention has been paid to the 60 GHz band where as much as 5 GHz of spectrum has been reserved. However, in the indoor environment, the propagation of signals at this millimeter wave band is strongly hindered by walls, people and their movement, furniture, etc. As a result, a mobile user might experience frequent loss of connection as the user moves from one cell to another. In this paper, we propose a flexible and cost-effective Radio-over-Fiber (RoF) based network architecture to support indoor networking at millimeter wave bands. To create sufficient overlap areas between cells and thus to ensure a seamless communication environment for mobile users, the concept of Extended Cell is introduced. We demonstrate the effectiveness of the proposed architecture with a detailed simulation study of an indoor scenario. Furthermore, we analyze the impact of the architecture on the performance of two popular state-of-the-art protocols, namely IEEE 802.11 and IEEE 802.16, to find which Medium Access Control (MAC) protocol is suitable for RoF networks. 相似文献
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建立了一个光载无线通信(RoF)与功率放大器(PA)结合的无线通信系统的数字预失真仿真结构,使用Matlab软件建立RoF和PA的模型,并运用间接学习结构的预失真方法和最小均方误差(LMS)算法搭建了预失真仿真系统,采用联合补偿和单独补偿两种方式的补偿结构,分析了两种结构的优缺点。通过功率谱密度图的对比,分析了两种补偿方式的效果。仿真结果表明,预失真处理有效地补偿了RoF与PA组成的无线通信系统的非线性。 相似文献
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为了改善高频微波进行长距离传输时具有很大的损耗,频率向高频扩展受限的特性。本文基于微波信号光纤
传输 (RoF)技术,采用波长为1550nm 的多量子阱分布式反馈激光器和数据速率高达10Gbps 的数字式PIN 光电探测
器,设计了一款工作频率为10MHz~4GHz 的超宽带微波光电子系统。在整个频率范围内满足了8dB 增益,增益平坦度
? 1.5dB 及输入/输出驻波比<2 的指标要求,符合工程需要,实现了数字式光电子器件在模拟通信中的应用,具有广泛
的应用范围。 相似文献
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