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1、外文文献及译文北京信息科技大学毕业设计（论文）附录题 目： 光纤通信在配电网自动化上的应用 学 院： 信息与通信工程学院 专 业： 通信工程 学生姓名： 闫润恒 班级/学号 通信1103/2011010431 指导老师/督导老师： 杨炜 起止时间：2015 年 3月 15 至 2015 年 6月 10日 目 录附件1：外文文献原文共7页附件2：外文文献译文共 5 页Optical fiber communication in power distribution automation applications on paper1. ForewordWith the development of
2、 national economy and peoples living standards improve, peoples growing demand for electricity, while the reliability and power quality of power supply put forward higher requirements. Feeder Automation is the reliability of power supply distribution network systems to improve the most direct and ef
3、fective means of technology. Countries has increased in recent years on the city network and the transformation of rural power network, power supply bureaus of the major domestic investment in distribution automation is also increasing. Achieved in the distribution network automation process, we fou
4、nd that communication problems is a difficult problem. In this, just from the fiber-optic communication networks in automation applications with little knowledge about and experience.2. Overview of optical fiber communication2.1 Mainstream optical network 2.1.1 Fiber optic technology Optical fiber p
5、roduction technology is now mature and is now mass-produced, widely used today is the zero-dispersion wavelength 0 = 1.3m single-mode optical fiber, while the zero-dispersion wavelength 0 = 1.55m single-mode optical fiber has been developed and has entered the practical stage, it is very small atten
6、uation in the 1.55m wavelength, about 0.22dB/km, it is more suitable for long distance and large capacity, is the preferred long-distance backbone transmission medium. Currently, in order to adapt to the different lines and LAN development requirements, has developed a non-fragmented fiber, low disp
7、ersion slope fiber, large effective area fiber, water peak fiber, and other new optical fiber. The people of the long wave optical research, the transmission distance can reach several thousand kilometers in theory, can be achieved without relay transmission distance, but its still a theory of stage
8、s.2.1.2. Fiber amplifier1550nm erbium-doped (Er) fiber amplifier (EDFA), erbium-doped fiber amplifier for digital, analog, and coherent optical communications repeater can transmit a different rate, and can also transmit certain wavelengths of light signals. In the fiber-optic network upgrade from a
9、nalog signals into digital signals, from low bit rate to high bit rate, the system uses light multiplexing expansion, they all do not have to change the erbium-doped amplifier circuits and equipment. Erbium-doped amplifiers can be used as optical receiver preamplifier, optical transmitter of the pos
10、t amplifier and the compensation amplifier light source device.2.1.3. Broadband accessDifferent environment business and residential customers a variety of broadband access solutions. Access system was completed for three main functions: high-speed transmission, multiplexing / routing, network exten
11、sion. Currently, the mainstream technologies access systems, ADSL technology it can be twisted-pair copper wire transfer economically bits of information few megabytes per second, which is to support traditional voice services, but also to support data-oriented Internet access, the Council end ADSL
12、access multiplex multiplexed data traffic, the routing to the packet network, voice traffic will be transmitted to the PSTN, ISDN or other packet networks. Cable modem in HFC network to provide high-speed datacommunications, it will be divided into upstream bandwidth coaxial cable channels and downl
13、ink channels, which can provide VOC-line entertainment, Internet access and other services, while also providing PSTN services. Fixed wireless access systems such as smart antennas and receiver uses many high-tech, is an access technology in innovative ways, is currently the most uncertain access te
14、chnology as a way of still practice in the future further exploration. The optical access system can provide enough bandwidth to support all currently foreseeable business, but there are still technical and economic problems need to be in the product development and technical innovation in order to
15、make it a 21st century network access system mainstream technology.2. 2Access NetworkThe so-called access network is the exchange between the Bureau to the user terminal equipment, all machine lines (the physical location of the access network), in which the backbone system for traditional cable and fiber optic cable, usually several kilometers long; wiring system may be cable and optical cable generally a few hundred meters in length; the introduction of a few meters to tens of meters long lines often.ITU-T requirements, access network refers to business contacts Interface (SNI) and the ass
