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将光通信技术的成本低、带宽大、损耗小、抗电磁干扰的优势和无线毫米波通信系统结合起来而产生的毫米波光载无线(MM—RoF)系统,具有带宽大、体积小、重量轻、成本低、损耗小、抗电磁干扰及传输质量高等优点。MM—RoF可解决传统微波传输系统在毫米波段存在的损耗大、抗干扰能力弱等问题,同时可克服毫米波电子器件的电子“瓶颈”问题,非常有发展潜力。多格式多业务的MM—RoF技术将是MM—RoF系统今后发展的一个重要方向。 相似文献
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OFM光生毫米波RoF系统的Optisystem实验仿真 总被引:1,自引:0,他引:1
光生毫米波技术是实现光纤无线(RoF)系统的一个关键因素,光学倍频法(OFM)是一种经济的光生毫米波方法.文章采用优秀的Optisystem光通信仿真软件,首先对OFM光生毫米波技术进行了实验分析;然后构建了加载NRZ强度和DPSK相位调制数据格式的RoF系统,对其传输性能进行了实验验证.结果表明:借助OFM光生毫米波技术实现超宽带无线接入的有效性. 相似文献
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概述了光载无线电(RoF)技术的最新发展及其特点,简述了光子产生毫米波、光子微波滤波、全光频率变换等RoF光子系统的关键技术,展现了RoF网络融合技术的广阔应用前景. 相似文献
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随着光纤无线(Radio-over-Fiber,RoF)技术逐渐成熟,下一代光接入网致力于提供有线和无线双重服务.采用Optisystem光通信仿真软件搭建了加载差分相移键控(DPSK)相位调制数据格式的有线与无线混合接入RoF系统模型,利用光分插复用器(IL)实现毫米波与基带信号的同时调制与传输.毫米波和基带信号的频谱图和眼图的仿真结果验证了该系统的有效性与可靠性. 相似文献
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基于相位调制器倍频技术产生56GHz毫米波的光载无线通信系统 总被引:2,自引:1,他引:2
提出并实验研究了一种基于光相位调制器(PM)倍频技术产生56GHz毫米波的光载无线通信(RoF)系统。在中心站,通过28GHz射频(RF)信号驱动PM产生了56GHz光毫米波,并将下行的2.8Gb/s开关键控(OOK)信号调制到该光载波上,然后经过20km标准单模光纤(SSMF)传输至基站,最后由天线进行发射。用户终端接收后,采用相干解调恢复出基带信号。实验结果表明,56GHz光载毫米波信号经SSMF传输20km后其功率代价小于1dB,通过无线方式传输1.1m后其功率代价小于2.5dB。 相似文献
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OCDMA技术是新一代的全光技术,可以广泛用于光信道多路复用、光网络多址接入、光码标记交换核心网、光信号安全传输、光纤传感以及光栽无线系统等.概述了光码分多址(OCDMA)技术的研究现状、主要关键技术,并展望其发展趋势和应用前景. 相似文献
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Hong-wei CHEN Mo LI Tian-liang WANG Fei-fei YIN Shi-guang WANG Ming-hua CHEN Shi-zhong XIE 《中国邮电高校学报(英文版)》2009
Key technologies and new system designs for various radio over fiber (RoF) applications are proposed and demonstrated. For ultrawideband (UWB) over fiber applications, several UWB pulses generation and distribution methods are carried out. Different kinds of UWB pulses are generated based on cross-polarization modulation methods. For millimeter-wave (mm-wave) wireless applications, a 32 GHz RoF system is demonstrated with microwave frequency sextupling by optical methods. After 20 km SMF transmission, the power penalty of 2.5 Gbit/s downlink service is less than 0.15 dB. It is also suitable to apply dense wavelength division multiplexing (DWDM) technology to RoF system to support numerous base stations (BSs). 相似文献
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光纤无线电技术是近年发展起来的一种新兴宽带传输技术,满足日益增长的用户带宽需求和灵活的移动接入。然而,由于电光转换的非线性失真和无线信道的多径衰落,接收信号会受到干扰的影响而恶化,因而需要采用均衡技术对信道响应进行补偿。文中将上行信道等效为Wiener模型,接收端均衡器首先补偿光纤信道的非线性失真,减少交扰调制失真,然后采用判决反馈结构的均衡器对无线信道的响应进行补偿减少码间干扰。仿真结果验证了该方法的有效性。 相似文献
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光载无线电(RoF,Radio-over-Fiber)技术是无线宽带接入的发展趋势,这项技术是把射频(RF,Radio Frequency)副载波调制到光载波上,从而在光纤网络中传输。它结合光纤通信和无线通信两大技术,可以实现超过Gb/s的无线业务传输,在未来高速宽带无线通信系统中具有重要的应用。在RoF系统中使用光纤传输的优点是高带宽、低损耗,不受电磁干扰、串扰小,重量轻、投资小、灵活性高等。主要介绍RoF系统的结构,优势、限制以及关键技术等。 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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Radio over fiber (RoF) is a very attractive and promising technology for wireless access networks, because of several advantages such as providing huge bandwidth, inherent immunity to electromagnetic interference and reduced power consumption. The analog RoF networks cannot be used for the transmission of radio signals over long lengths of fiber due to the distortions induced by dispersion and nonlinearity of the optical link. The digitized RoF communication presents an interesting alternative to circumvent the limitations of ARoF networks. In this paper, we propose an all-optical DRoF (Digital RoF) scheme based on the optical encoding technique and optical codewords instead of modulation techniques. The proposed scheme is composed of an all-optical sampler, an all-optical thresholder and an all-optical encoder. The proposed all-optical DRoF design is simulated by implementing its three main components using the simulation platform, Optisystem. We have also studied the capacity of the proposed encoding architecture in terms of the maximum number of chips that can be supported. Furthermore, ARoF, DRoF and the proposed all-optical DRoF systems are compared based on the minimum bit error rate, the maximum quality factor, and the complexity and implementation cost. 相似文献
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This paper presents an overview on new progresses-of millimeter wave (mm-wave) radio-over-fiber (RoF) system based on mm-wave generation by optical frequency multiplication (OFM), including gen-eration of high-order optical side modes by optical modulation using dual-drive Mach-Zehnder modulator (DD-MZM) and enhancement of high-order optical side mode induced by selective amplification due to stimulated Brillouin scattering (SBS). The paper describes OFM by using DD-MZM in principle and verifies it in an experimental bidirectional 40GHz RoF system. SBS amplification enhances the generated information-bearing mm-wave in downlink and also helps in producing a pure reference mm-wave for radio frequency-intermediate frequency (RF-IF) down-conversion in uplink. These efforts pushed the OFM technology of mm-RoF systems to achieve more and more feasibility and cost-effectiveness. 相似文献
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Radio-over-Fiber ( RoF ) technologies have been considered to be a promising solution to broadband access and ubiquitous sensing. We present a novel approach using dual-wavelength lights to suppress the nonlinear intermodulation distortion in intensity-modulated RoF link both theoretically and experimentally. The system we proposed mainly consists of two Laser Diodes (LDs ) at different wavelengths, a commercial available Mach-Zehnder Modulator (MZM) and a Photo Detector (PD). More than 25 dB suppression of the Third-order Intermodulation Distortion (IMD3) is achieved by adjusting the wavelength and optical power of the laser. Besides , the output of the MZM is then sent to the photodetector via a single fiber, which simplifies the system complexity for distribution of RF signals over long distances . 相似文献