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Provide a peace of mind High-Capacity Optical Communications (Next-Generation Communication Network)

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High-Capacity Optical Communications Requiring Advanced Technologies in Unseen Areas

High-Capacity Optical Communication Technology of the Furukawa Electric Group

As is shown in its world's first success of a practical optical fiber cable in 1974, Furukawa Electric has been energetically engaged in the technological innovation of optical fiber communications in pioneer days. Its frontier spirit has been inherited in an unbroken line today, and we have been supplying a number of world-class products and technologies.

High-Capacity Optical Communication Technology
  • (A) Optical fibers (Ultra small loss and low non-linear)

    An optical fiber can perform high-capacity, high-speed, long-distance data transmission from trunk line through metro to access line. We provide optical fibers capable of further high-capacity, high-speed, long-distance transmission aimed at the development of an IT society.

    • AllWave Zero-Water-Peak

      AllWave Zero-Water-Peak fiber is an optical fiber that makes future system upgrading easier, realizing a transmission line of long-term reliability in multi-wavelength transmission such as CWDM (Note 1).

    • TrueWave REACH Low-Water-Peak

      TrueWave REACH Low-Water-Peak fiber is a wideband nonzero dispersion shift fiber (NZ-DSF) (Note 2) that meets the international standard of ITU-T G.655.C, G.655.E and G.656. It is optimally designed to suit the optically amplified system of today that continues to grow in speed and capacity.

    • LaserWave

      LaserWave multimode optical fiber (Note 3) is the first optical fiber that has expanded the transmission distance of 10-Gbps serial transmission using 850-nm VCSEL transceivers. In the near future, it will be applicable to short-distance optical transmissions of 40 Gbps and 100 Gbps.

    • FlexiWave

      When an optical fiber is bent, optical signals will leak out of the fiber to generate bending loss. And a large bending loss can cause a communication failure. FlexiWave is an optical fiber that has reduced its allowable minimum bending radius to 15 mm--half that of conventional single-mode optical fibers. With its reduced bending radius limitations, the fiber can reduce the wiring space about one quarter the conventional in area, making downsizing of equipment and termination boxes possible. It also achieves workability improvement and space saving during cable lead-in works and indoor cabling at FTTH implementation.

    • Multicore optical fiber

      This is a fiber having multiple cores in the same clad. We have been in research and development including its splicing method and optical amplification technology. The multicore fiber realizes the spatial multiplexing transmission.

  • (B) Waveguide type optical components (PLC)

  • The following functions are the essential functions for the wavelength division multiplexing (WDM) optical communication used in trunk communication networks and metro networks.

    • To multiplex optical signals of different wavelengths and to insert in one optical fiber.
    • To separate the optical signals into respective wavelengths, those signals are output from one optical fiber having plurality of wavelengths.

    This is the optical waveguide-type optical components to achieve these functionalities.

    In case of the ultra-high-speed optical transmission exceeds 40 Gbps (Note 4), the conventional two values intensity modulation method to ON/OFF the light intensity causes significant degradation of transmission quality (Note 5). Then, the optical digital coherent method utilizing the degradation difficult phase modulation is used. An optical circuit, which optically processes the polarization information and phase information of optical signals received by the digital coherent communication (Note 6) and transfers to high speed digital signal processor, is realized with Planar Lightwave Circuit (PLC).

  • (C) Semiconductor lasers

  • Semiconductor lasers are used as light sources for optical communication. In the initial stage of the optical communication, lasers of a single wavelength were mainstream, however, in accordance with the generalization of wavelength division multiplexing communication, it became difficult to make up the backup laser of each wavelength, and a tunable (wavelength tunable) laser became to be required.

    In addition, amplification of the signal is necessary for long distance communication. In the initial stage, optical signals were converted to electrical signals and put back on the new light. By the development of the technology to amplify optical signal as it is, the amplification efficiency was extremely improved.

    • Integrated Tunable Laser Assembly (ITLA)

      ITLA mounts a laser module to cover wave bands of C band (from 1530 to 1565 nm) and L band (from 1565 to 1625 nm) on the electric substance. Miniaturization and electric power saving are the keywords to achieve high-capacity communication, and we are working for realization.

    • High-output excitation laser diode module

      To amplify optical signal as light, a specific waveband, which is different from the signal, of light is entered (wave combining). The light is named as excitation light, the higher the laser output is the higher amplification is available, and amplifiers setting interval can be extended, then the amplifier amount can be decreased. Furukawa Electric has been developing and manufacturing the world top level of high-output excitation laser.

  • (D) Optical interconnections

  • Optical signal transmission has many merits such as high-speed and high-capacity transmission, electromagnetic resistance, space saving wiring and countermeasure against heat, then in various electric transmission applications are replaced to the light. For example, data amount on networks is rapidly increasing by video distribution and others.

    Even server performance is improved, if transmissions speed between equipments are slow, network performance is degraded. For the resolution of this bottleneck, optical interconnection (Note 7) can contribute. In addition, by applying the optical inter connection to the wiring in and between equipments of routers and servers, which are ever-increasing); it can contribute to effectiveness of operation such as elimination of complex wiring and simplification on countermeasure against heat.

    • Compact parallel optical engines

      This is a compact parallel optical engine for high-density optical interconnections that enables rack-to-rack and board-to-board interconnections higher than 10 Gbps per channel in speed--unattainable with electric transmission. With its compact size, the engine allows for embedding in optical transceivers of various shapes as well as mounting on boards.

    • High-density optical fiber connectors

      density. This connector contributes not only to the size reduction and mounting density upgrading of connecting components, but also to significant space savings, when combined with the optical fiber that achieves a small bending radius less than 30 mm of the conventional.

  • (E) Optical communication systems

  • This is the system to realize delivery and reception of large-volume contents. Based on access system using optical fiber, video, internet, phone call and various communication and contents are delivered.

    • Broadband communication systems

      Based on a broadband communication system, it is possible to construct an access network which enables enjoying simultaneous viewing of more than 100 channels of high-definition pictures and 3D pictures, and telephone service with a quality level equivalent to that of dedicated lines, along with high-capacity Internet access higher than 1 Gbps.

  • (F) Router

  • A router is a routing device in a communication network. Furukawa Electric is improving the performance of advanced network constructing routers aimed at New Generation Network etc. We provide multiservice routers to offer flexible solutions for integrating various services such as VPN (Note 8), multicast (Note 9) and audio/video delivery with next-generation IP networks.

    • Multiservice router

      This is a high-performance service router provided with not only high-speed and high-capacity functionality but also compatibility with encrypted communications, using a dedicated processor. It does not need any equipment rebooting at the time of firmware updating, thus contributing to constructing stabilized networks.

* AllWave, TrueWave, LaserWave are registered trademarks of OFS in the United States.

(Note 1) CWDM :
Abbreviation of "coarse wavelength division multiplexing", meaning a WDM transmission service for relatively short distances. While one or two amplifiers are need for 80-km communications typically, the CWDM allows high-speed communications at low costs since it introduces no amplifiers.

(Note 2) NZ-DSF (Nonzero dispersion shift fiber) :
A kind of single-mode optical fiber designed to avoid interference among wavelengths in the WDM transmission and thus to reduce the transmission loss.

(Note 3) Multimode optical fiber :
Although its transmission distance becomes shorter than that of single-mode fiber, the costs of optical fiber and connecting parts can be suppressed thanks to its large core diameter where light passes. * AllWave is a registered trade mark of OFS.

(Note 4) 40 Gbps :
A data rate of forty billion bit per second.

(Note 5) Wavelength dispersion and polarization mode dispersion are factors to degrade the transmission quality.

  • Wavelength dispersion
    When light is input into a prism, rainbow colors can be viewed. This phenomenon can be observed because the reflective index of glass changes depending on the wavelength of light. Different refractive index means that when a light wave is input into a fiber the path the light propagates in the fiber becomes slightly different according to the wavelength, and that the light that propagates a longer path takes a longer time for communication. The same is true with optical fiber in that when a light wave comprising different wavelengths is input an optical fiber, the arrival time of each wavelength at the output (receiver side) becomes slightly deviated after travelling the same distance. This deviation on the receiver side due to wavelength difference is called the wavelength dispersion, and this is a contributing factor to increase bit errors.
  • Polarization mode dispersion
    Light is a kind of electromagnetic wave with characteristics of transversal wave. Its field looks like a wave in shape when observed from the lateral side of fiber, but from the cross-section of fiber it may look like a straight line, circle or ellipse, which is called the polarization mode. The generation of propagation time deviation due to different polarization modes is called the polarization mode dispersion, and this is a contributing factor to increase bit errors.

(Note 6) Coherent communication :
This is one of the high-capacity transmission methods based on optical fiber transmission systems, in which multiple light beams slightly different in frequency and wavelength are simultaneously transmitted and received to multiplex the carrier waves. It is a collective designation of optical frequency-division multiplexing transmission method (optical FDM) and optical wavelength-division multiplexing transmission method (optical WDM).

(Note 7) Optical interconnection :
A wiring technology using light targeted at applications in devices or on boards.

(Note 8) VPN (Virtual Private Network) :
With this method, open networks can be used in a virtual manner as if they were a privately owned exclusive network.

(Note 9) Multicast :
A method with which the same data are transmitted to plural destinations predetermined by negotiation etc. This method is used, for example, to deliver videos to specified majority.


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