• 山西首届百名金牌导游大赛太原选拔赛3月8日鸣锣 2019-09-19
  • 比利时建议每周饮酒别超过10杯 2019-09-14
  • 袁家军:坚定不移打赢新时代禁毒人民战争 2019-09-11
  • 【重庆天气】最新重庆今天天气,实时提供重庆气温、空气质量、24小时天气预报、生活指数查询 2019-09-11
  • 香港举行春节彩灯展(1) 2019-08-28
  • 三晋史话:发生在山西境内的那些上古神话故事 2019-08-28
  • 任性海雕同滑翔机模型天空竞速 上演“比翼双飞” 2019-08-28
  • 理上网来·辉煌十九大 2019-08-22
  • 山西:今年汛期降雨量偏多 各部门未雨绸缪全力备汛 2019-08-19
  • 百年美洲杯决赛阿根廷vs智利 在线直播观看 梅西能否封王 2019-08-19
  • 平安智慧城创新车险投保全程线上化 深圳司机开车已不用带保险单了 2019-08-18
  • 建设学习型服务型创新型党组织创新案例 2019-08-10
  • 中国国际智能产业博览会LOGO征集选用公告 2019-08-10
  • 沈阳学区划分方案8月中下旬公布 2019-08-04
  • 初二少年与家长争吵离家出走 客运站人员发觉异样后拦下 2019-08-04
  • Solutions Solutions
    最新新闻 / News More
    1
    2018 - 10 - 10
    AfricaCom is the biggest, best and most influential Tech & Telecoms event on the continent of Africa. It’s a place to meet everybody who’s anybody in African telecoms and technology, AfricaCom brings together 14,000 attendees, 450 speakers and 400 exhibitors. XDK will be exhibiting for the second time.   Whether your focus is connectivity, Infrastructure, disruptive technologies, digital series or ICT strategy, this is the place to network, learn and get deals done with us. We bring high density connectivity products to your business at the heart of African Tech &a...
    联系我们
    移动云网站
    销售热线:0755-2729 6565
    公司总机:0755-2775 9293
    图文传真:0755-2788 8009
    总部地址:深圳市宝安区航城大道西乡光电研发大厦二楼

    WDM Solution

    release date: 2014-07-01
    Browse popular: 333

    天津快乐10分走势图一定牛 www.unxkf.tw WDM Solution


    ? ? The emergence of DWDM is one of the most recent and important phenomena in the development of fiber optic transmission technology. This tutorial will introduce the fundamentals of DWDM technology, such as the components, optical amplifiers used in DWDM system, etc.


    Components and Operation

    ? ??DWDM is a core technology in an optical transport network. The essential components of DWDM can be classified by their place in the system. On the transmit side, there are lasers with precise, and stable wavelengths. On the link, there is optical fiber that exhibits low loss and transmission performance in the relevant wavelength spectra, in addition to flat-gain optical amplifiers to boost the signal on longer spans. On the receive side, there are photodetectors and demultiplexers using thin film filters or diffractive elements. Besides these components, optical add/drop multiplexers and optical cross-connect components may be used.

    The main job of optical fibers is to guide lightwaves with a minimum of attenuation (loss of signal). Multimode fiber and single-mode fiber are the general two categories of optical fiber in use today. Single-mode fiber has a much smaller core that allows only one mode of light at a time through the core. As a result, the fidelity of the signal is better retained over longer distances, and modal dispersion is greatly reduced. These factors attribute to a higher bandwidth capacity than multimode fibers are capable of. For its large information-carrying capacity and low intrinsic loss, single-mode fibers are preferred for longer distance and higher bandwidth applications, including DWDM.

    WDM Solution

    Erbium Doped Fiber Amplifier (EDFA)

    ? ??By making it possible to carry the large loads that DWDM is capable of transmitting over long distances, the?EDFA?was a key enabling technology. Erbium is a rare-earth element that, when excited, emits light around 1.54 micrometers—the low-loss wavelength for optical fibers used in DWDM. The picture below shows a simplified diagram of an EDFA. A weak signal enters the erbium-doped fiber, into which light at 980 nm or 1480 nm is injected using a pump laser. This injected light stimulates the erbium atoms to release their stored energy as additional 1550-nm light. As this process continues down the fiber, the signal grows stronger.

    ?WDM Solution

    Multiplexers and Demultiplexers

    ? ??As DWDM systems send signals from several sources over a single fiber, they must include some means to combine the incoming signals. This is done with a multiplexer, which takes optical wavelengths from multiple fibers and converges them into one beam. At the receiving end, the system must be able to separate out the components of the light so that they can be discreetly detected. Demultiplexers perform this function by separating the received beam into its wavelength components and coupling them to individual fibers. Demultiplexing must be done before the light is detected, because photodetectors are inherently broadband devices that cannot selectively detect a single wavelength.

    In a unidirectional system, there is a multiplexer at the sending end and a demultiplexer at the receiving end shown in the following picture. Two system would be required at each end for bidirectional communication, and two separate fibers would be needed.

    ?WDM Solution

    ? ??In a bidirectional system, there is a?multiplexer/demultiplexer?at each end and communication is over a single fiber pair.

    ?WDM Solution

    ? ??Multiplexers and demultiplexers can be either passive or active in design. Passive designs are based on prisms, diffraction gratings, or filters, while active designs combine passive devices with tunable filters.


    Optical Add/Drop Multiplexers (OADM)

    ? ??Between multiplexing and demultiplexing points in a DWDM system, there is an area in which multiple wavelengths exist. It is often desirable to be able to remove or insert one or more wavelengths at some point along this span. An optical add/drop multiplexer performs this function. Rather than combining or separating all wavelengths, the?OADM?can remove some while passing others on. OADM is a key part of moving toward the goal of all-optical networks.

    ?WDM Solution

    ? ??There are two general types of OADMs. The first generation is a fixed device that is physically configured to drop specific predetermined wavelengths while adding others. The second generation is reconfigurable and capable of dynamically selecting which wavelengths are added and dropped.


    Operation of a Transponder Based DWDM System

    ? ??Within the DWDM system, a transponder converts the client optical signal. The following picture shows the end-to-end operation of a unidirectional DWDM system.

    ?WDM Solution

    The following steps describe the system shown in the picture above.

    1. The transponder accepts input in the form of standard single-mode or multimode laser. The input can come from different physical media and different protocols and traffic types.

    2. The wavelength of each input signal is mapped to a DWDM wavelength.

    3. DWDM wavelengths from the transponder are multiplexed into a single optical signal and launched into the fiber. The system might also include the ability to accept direct optical signals to the multiplexer; such signals could come, for example, from a satellite node.

    4. A post-amplifier boosts the strength of the optical signal as it leaves the system (optional).

    5. Optical amplifiers are used along the fiber span as needed (optional).

    6. A pre-amplifier boosts the signal before it enters the end system (optional).

    7. The incoming signal is demultiplexed into individual DWDM lambdas (or wavelengths).

    8. The individual DWDM lambdas are mapped to the required output type (for example, OC-48 single-mode fiber) and sent out through the transponder.


    Click to view the product


    上一篇:没有上一篇了下一篇:没有下一篇了
    推荐新闻
    X
    等待加载动态数据...

    等待加载动态数据...

    等待加载动态数据...

    等待加载动态数据...

    等待加载动态数据...

    等待加载动态数据...

    等待加载动态数据...

    等待加载动态数据...

    等待加载动态数据...

    等待加载动态数据...

    等待加载动态数据...

    等待加载动态数据...

    等待加载动态数据...

    等待加载动态数据...

    展开
  • 山西首届百名金牌导游大赛太原选拔赛3月8日鸣锣 2019-09-19
  • 比利时建议每周饮酒别超过10杯 2019-09-14
  • 袁家军:坚定不移打赢新时代禁毒人民战争 2019-09-11
  • 【重庆天气】最新重庆今天天气,实时提供重庆气温、空气质量、24小时天气预报、生活指数查询 2019-09-11
  • 香港举行春节彩灯展(1) 2019-08-28
  • 三晋史话:发生在山西境内的那些上古神话故事 2019-08-28
  • 任性海雕同滑翔机模型天空竞速 上演“比翼双飞” 2019-08-28
  • 理上网来·辉煌十九大 2019-08-22
  • 山西:今年汛期降雨量偏多 各部门未雨绸缪全力备汛 2019-08-19
  • 百年美洲杯决赛阿根廷vs智利 在线直播观看 梅西能否封王 2019-08-19
  • 平安智慧城创新车险投保全程线上化 深圳司机开车已不用带保险单了 2019-08-18
  • 建设学习型服务型创新型党组织创新案例 2019-08-10
  • 中国国际智能产业博览会LOGO征集选用公告 2019-08-10
  • 沈阳学区划分方案8月中下旬公布 2019-08-04
  • 初二少年与家长争吵离家出走 客运站人员发觉异样后拦下 2019-08-04
  • 极速时时可以玩吗 一码中特是什么王中王肖 足球即时波胆网 腾讯分分彩资料计划 功夫足球 娱乐平台 上海快3详情 广东快乐十分公式破解 重庆时时怎么赚钱 甘肃11选5开奖