Optical Submarine Cable System Research Articles

(Invited) Dispersion managed solitons and their application to high-capacity optical submarine cable systems

(Invited) Dispersion managed solitons and their application to high-capacity optical submarine cable systems

Trans-Pacific class transmission over a standard cladding ultralow-loss 4-core fiber

The total capacity of optical submarine cable systems as a global communication infrastructure must be continuously enlarged. Multi-core fibers (MCFs) have been studied as methods to maximize the total cable capacity under electrical power and cable space limitations. In particular, standard cladding MCFs, which are expected to have high productivity and mechanical reliability, are attractive for early deployment in submarine cable systems. In this paper, we demonstrate high-capacity trans-Pacific class transmission using standard cladding uncoupled 4-core fibers, achieving a transmission capacity of 55.94 Tbit/s over 12,040 km. In addition, based on the results of this and our previous coupled MCF transmission experiments, we summarize the characteristics of coupled and uncoupled MCFs applied to optical submarine cable systems.

50.47-Tbit/s Standard Cladding Coupled 4-Core Fiber Transmission Over 9,150 km

Since optical submarine cable systems are a part of the global communications infrastructure, their total capacity must be continuously and dramatically enlarged. Recently, methods how to maximize the transmission capacity under electrical power limitations have been studied, and it has been reported that a single band (C-band only) transmission system with more fiber pairs (FPs) could be a promising technology. This finding has triggered work on submarine cables with more FPs. For a further increase in FPs in optical submarine cable systems, which also have space limitations in existing cable designs, space-division multiplexing (SDM) technologies such as multi-core fibers (MCFs) and multi-mode fibers (MMFs) could be promising solutions. In particular, 125-μm standard cladding SDM fibers are attractive for early deployment in submarine cable systems since they are expected to have high productivity and high mechanical reliability similar to existing single-mode fibers (SMFs) with the same cladding diameter. In this paper, we report transpacific MCF transmission over a 30-nm bandwidth using standard cladding ultralow-loss coupled 4-core fibers, extending our previous work. The Q <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> -factors of 608 (4 core × 152 WDM) SDM/WDM channels modulated with 24-Gbaud DP (dual polarization)-QPSK (quadrature phase shift keying) exceeded the assumed forward error correction (FEC) limits after a 9,150-km transmission. As a result, transmission capacity of 50.47 Tbit/s and a capacity-distance product of 461.8 Pbit/s·km were achieved for standard cladding diameter SDM fibers.

Technological Innovation and Challenges Facing Optical Submarine Cable Systems

Technological Innovation and Challenges Facing Optical Submarine Cable Systems

Review on recent optical submarine cable network systems - 3. Terminal equipment and related technologies for optical submarine cable system.

Review on recent optical submarine cable network systems - 3. Terminal equipment and related technologies for optical submarine cable system.

Review on recent optical submarine cable network systems - 1. Review of current and future trend of optical submarine cable systems.

Review on recent optical submarine cable network systems - 1. Review of current and future trend of optical submarine cable systems.

Review on recent optical submarine cable network systems - 4. The latest technological trend of optical submarine cable.

Review on recent optical submarine cable network systems - 4. The latest technological trend of optical submarine cable.

Review on recent optical submarine cable network systems - 2. Transmission technologies for high-capacity long-haul optical sibmarine systems.

Review on recent optical submarine cable network systems - 2. Transmission technologies for high-capacity long-haul optical sibmarine systems.

Review on recent optical submarine cable network systems - 5. Ocean bottom earthquake observation.

Review on recent optical submarine cable network systems - 5. Ocean bottom earthquake observation.

Optical Submarine Cable System Technologies: Present and Future

Optical Submarine Cable System Technologies: Present and Future

Design Requirements for the Current Generation of Undersea Cable Systems

This article describes the design requirements of AT&T's third generation of optical submarine cable systems. Technology advances that have been incorporated in the design include erbium-doped fiber amplifiers, lithium niobate modulators, low-loss and low-polarization mode dispersion-shifted fiber, synchronous digital hierarchy terminals, and forward error correction. This paper discusses: — Optical submarine cable systems, — Customer requirements, — New technologies used in system design, — System building blocks, — System performance, and — System and component design rules to meet customer requirements.

Optical fiber submarine cable systems

Optical fiber submarine cable systems especially developed for international systems throughout the world are reviewed, and the future technologies for optical fiber submarine cable systems are discussed. The discussion covers: system design; cable design and the fiber used; mechanical design of submarine optical repeaters; branching repeaters; repeater circuits; reliability; terminal equipment; repeater supervisory systems; initial system applications; and future trends. >

Three Dimensional Dynamic Analysis for Laying and Recovery of Optical Submarine Cables

The author has developed two types of cable laying simulation programs based on three dimensional dynamic analysis method in order to analyze dynamic behavior of cables, repeaters and branching unit during laying and recovery.One is a computer simulation program for laying and recovery of submarine cables with repeaters. This program has following two new functions is addition to conventional cable laying simulation.(1) Slack control laying function. The cable pay-out speed is automatically calculated by internal feed back loop so as to make bottom cable slacks be constant. Using this function, the optimum cable pay -out speed history can be obtained by giving the bottom profile and cable ship speed profile.(2) Tension control laying function. The cable pay-out speed is automatically calculated by internal feed back loop so as to make shipboard tension be constant. The speed error of cable ship measured by 'taut wire' is discussed using this program. This error is exactly analyzed using this tension control laying simulation.The other is a computer program for laying and recovery submarine cables with a cable branching unit. The cable branching unit (BU) is newly installed to the optical submarine cable systems. This newly developed program can analyze dynamic behavior of BU and cables around it, and help to study how to lay BU with sufficient cable slacks and recover it safety.The sea trial was carried out in order to measure hydrodynamic constant of the submarine cable and verify this computer simulation method at the depth of 6000m by attaching sensors to the submarine cable at some intervals. According to the sea trial, the normal drag coefficient Cd was measured to 2.5, andd the cable configuration measured by this experiment was in good agreement with the result of the computer simulation.

First field demonstration of optical submarine cable system using LD-pumped Er-doped optical fibre amplifier

This is a report on the first field demonstration of an optical submarine cable system using an in-line Er-doped optical fibre amplifier pumped by a 1.47μm laser diode. The experiment was performed at an ocean depth of 3000 m. With a maximum optical repeater gain of 20 dB, l.2 Gbit/s intensity-modulated optical signals were transmitted stably during and after installation and also during recovery of the system. Furthermore, the effectiveness of an automatic-gain-control (AGC) scheme proposed for optical amplifiers was confirmed in a practical environment.

High reliability planar-type GaInAs/InP heterostructure avalanche photodiodes

High-temperature, long-term life tests of GaInAs/InP heterostructure avalanche photodiodes have been carried out to establish criteria for high reliability photodetectors in 1.55μm-wavelength optical submarine cable systems. A failure rate of less than 0.2 FIT at 10°C was predicted for the first time with an activation energy of 0.7 eV.

The design and realization of a high reliability semiconductor laser for single-mode fiber-optical communication links

Long-haul trunk telecommunication systems, particularly optical submarine cable systems, have especially demanding reliability requirements. The authors describe how the InGaAsP inverted-rib waveguide (IRW) laser was designed for use as the source for such single-mode systems by minimizing known degradation hazards. The results of an extensive reliability assurance program are summarized. This included wafer validation endurance tests, overstress tests, and package design and life tests. The results of 7 million life-test hours confirm that the IRW laser has extremely good reliability performance. >

Submarine optical fibre cable system applications

The transition from analogue coaxial cable to digital optical fibre submarine systems has required a new technology to be established and complementary technologies to be developed for the design, evaluation and operational support of these new systems. The common design parameter throughout is reliability; not only must the overall system design satisfy the reliability objective but the component parts must be shown to exhibit the necessary low level of failure for this to be achieved.1988 sees the commissioning of TAT-8, the first trans atlantic optical fibre submarine cable system. In addition a number of submarine cable systems linking the UK mainland with other British Islands and Europe will be made available. This paper reviews the current generation of submarine cable systems based on 1.3μm and emerging 1.55μm technologies and discusses the opportunities offered to planners and network operators from developments in networking, optical repeaters and non-silica fibres.

Reliability of the OS-280M Optical Submarine Repeater

The development phase of the OS-280M optical submarine cable system is finished, and currently the mass production lines for the system are arranged so as to satisfy the specific performances and the reliability requirements for the TPC-3 system within its system life of 25 years. KDD developed the reliability assurance system of the repeater components, which began three years ago. In this paper, we will introduce the reliability design of the OS-280M system and will report on the reliability test results obtained until the present time. In conclusion, it will be demonstrated that all of repeater components, i.e., optical semiconductor devices, monolithic IC's, several kinds of optical devices, and conventional components could satisfy the reliability requirements for the OS-280M system.

Self-core-alignment arc-fusion splicer based on a simple local monitoring method

We have developed an arc-fusion splicer with a self-core-alignment function based on cladding-mode-leakage light power monitoring that incorporates a microprocessor, piezoelectric elements, and a photoreceiver with high sensitivity, for monitoring the leakage light power without bending the receiving fiber. The design and the performance of the splicer are presented. Using the splicer, we successfully demonstrate the splicings of single-mode fibers in a repeater section of an experimental optical submarine cable transmission system. The required time for one splicing including the self-core-alignment process is only 50 s and we have obtained extremely good results with an average splice loss of 0.035 dB for 100 splices at the far end of a 30-km-long single-mode fiber connected with a repeater.

A design and experimental results of the OS-280M optical submarine repeater circuits

This paper describes the design philosophy and the experimental results of the optical submarine repeater for the OS-280M optical fiber submarine cable system to be installed across the ocean. This repeater which employs the information rate of 280 Mbit/s, the optical wavelength of 1.3 μ, and is implemented with monolithic ICs, features high reliability, long repeater spans, and the supervisory systems. The test results show that the average optical output power is - 1.4 dBm for the mark density of 1/2, the minimum average power of the optical input for the BER 10 is about -38 dBm at the room temperature, and other specifications are also well satisfied.