Optical fibre cable with ultra-high density of more than 3 fibres/mm/sup 2/

Proposed is an ultra-high-density 100-fibre cable that uses 0.25 mm diameter mono-coated optical fibres with a low bending loss. This cable has great advantages in terms of cable weight and diameter and will be easy to install in a small space in underground ducts and/or on residential and business premises. The optical fibre with the optimum low bending loss is selected experimentally to obtain optical fibre cable with the maximum fibre density. A 100-fibre cable with a fibre density of more than 3 fibres/mm² and a cable diameter of 6.3 mm was obtained     

Ultra-high-density 1000-fibre cable with 5 fibre/mm

An ultra-high-density 1000-fibre cable is proposed, which uses mono-coated low-bending-loss optical fibres with a diameter of 0.25 mm. This cable has great advantages in terms of cable weight and diameter and will be easy to install in a small space in underground ducts. The selection of optical fibre with an optimum low bending loss and cable reliability are investigated experimentally for this cable in order to achieve the maximum fibre density and high reliability. A 1000-fibre cable with a fibre density of 5 fibre/mm and a cable diameter of 15.8 mm was obtained.     

Measurement of strain relief in an experimental optical fibre cable

Optical cables made by helically winding loose-tubed fibres around a central member can be designed to tolerate different amounts of axial strain before the fibres are strained. Here an optical technique is used to measure the strain relief achieved in an experimental cable incorporating fibres tubed under different conditions. The results are in good agreement with the strain relief predicted from the cable geometry.     

Uniform and low polarisation-mode dispersion in 100 fibre ribbonslotted core optical cable

Uniform and low polarisation-mode dispersion, 0.052 and 0.053 ps/√km on the average, has been confirmed in 100 fibre ribbon slotted core optical cable before and after installation, respectively. The cable has been manufactured with standard singlemode fibres having nearly optimised coating structure determined through finite element method analysis conducted to minimise lateral force induced birefringence     

Low loss high-density optical cable with nylon-extruded fibre units

A low loss, highly dense cable containing nylon-extruded six-fibre units was examined. Suitable unit parameters were determined by measuring loss increases with lateral force and at low temperature. 216-fibre cable was manufactured using the nylon-extruded units, and cabling loss increase was found to be only 0.1 dB/km.     

Optical loss measurement results on an experimental optical fibre submarine cable of 30 km length

A continuous length of 30 km optical fibre submarine cable was successfully manufactured and laid on the sea bed about 1000 m deep. After the sea trial of 17 months, the cable was recovered from the sea bed. No significant degradation was observed in the optical loss of the recovered cable.     

A radically new approach to the installation of optical fibre using the viscous flow of air

A method of installing optical fibres in pre-installed cable bores using compressed air has been developed. The method results in very low fibre strains and avoids the need for many fibre joints. Analysis of the forces involved shows that installations of 600 m in 6 mm bores are achievable using the compressors already available on UK cabling vehicles.     

Deep sea trial of 1.55 μm optical fibre submarine cable system

The first 6000 m deep sea trial of a 1.55 μm optical fibre submarine cable system was successfully conducted in the Pacific Ocean, near Torishima Island, in January 1988. By using 1.55 μm loss-minimised single-mode fibre cables and submerged fully monolithic Si-IC regenerators with DFB lasers, excellent transmission performances at 140, 280 and 565 Mbit/s were obtained through 150 km repeater spacings, respectively     

Ultralow-loss 220 km-long single-mode-fibre cable link in 1.5 ?m wavelength region

Ultralow-loss single-mode-fibre cables specially designed for the 1.5 ?m region were fabricated. The fibre parameters are a mode-field radius of 6 ?m and an effective cutoff wavelength of 1.4 ?m. The average loss is 0.19 dB/km at 1.55 ?m. The total loss of a 216 km-long cable link consisting of 2 km-long fibres with 107 splices was 46.3 dB. The cables also show a good loss stability at 1.55 ?m in long-term use.     

Fusion splicing of a 31.6 km monomode optical fibre system

The fusion splicing of a 14-fibre, 31.6 km-cabled, monomode optical fibre system, with a mean splice loss of 0.18 dB at ? = 1.3 ?m and 0.12 dB at ? = 1.55 ?m, is reported.     

Innovative approach to interspan fibre break location in fibre amplifier repeatered communication systems

A proposed modification to the component geometry of a fibre amplifier repeater which allows on on-board cable fault location facility to be incorporated is reported. The measurement technique, based on OTDR, allows cable breaks in the section of optical fibre between two fibre amplifier repeaters to be located.<>     

Infra-red optical loss increase for silica fibre in cable filled with water

Loss increase characteristics of optical fibre in cable filled with water are reported. Drastic loss increase around 1.24 ?m is observed for both graded-index and single-mode fibres. The origin of the loss increase is found to be due to hydrogen gas diffused into the silica glass interstitially.     

Suitable parameters of single-mode optical fibre

A new method for determining suitable single-mode fibre parameters is examined. Suitable fibre parameters are determinable by minimising cabling- and splicing-loss increases. An eight-fibre cable was manufactured and the loss increases were measured. ? = 0.2% and V = 2.2 are the values selected using this method and for the experimental results.     

Les télécommunications par câbles sous-marins: l’avènement des fibres optiques

This paper explains why the new generation of the submarine transmission systems by optical fibres has come into existence, ensuing from the telegraphic cables and coaxial cable systems. The author expounds how the main characteristics of this new system have been selected and describes its different elements such as its optical fibre, repeaters, branching units and the equipment of the terminal stations. The French program of study and development of the system is indicated and some thoughts are given to what the future in this particular field could be.     

Fabrication of a stress-guiding optical fibre

The principle of stress guidance in optical fibres is described. An optimum-stress-guidance structure has been designed and fabricated using gas-phase etching. The fibre is the first to have truly single-polarisation operation for all V-values.     

Cable television on fibre in stand-alone networks and in systems combined with telephony

This paper presents details of dedicated cable television systems (stand-alone cable TV), and combined cable TV/telephony systems, based upon the economic implementation of optical fibre technology. The factors that determine the choice of these two approaches are described and examples are given based upon systems designed by Raynet Corporation. Techno-economic issues are debated and the need for effective future-proofing is emphasized. In particular, the critical choice between fibre to the last amplifier (FTTLA) and fibre to the curb (FTTC) is discussed. Architectures are described for trunk and distributed systems and performance characteristics are given for a specific network, optical elements and electro-optic interfaces. Detailed considerations relating to future developments conclude the paper.     

Polarisation-maintaining single-mode fibre cable design

Guidelines for the design of a circular-polarisation-maintaining single-mode fibre cable are given. The use of circular polarisation allows use of low birefringence fibres and there is no need for orienting the fibres at splices. Quarter-wave plates at input and output of the fibres achieve the desired linear-circular polarisation conversion, and vice versa.     

Long-period fibre grating formation with 264 nm femtosecondradiation

A new approach for producing long period fibre gratings by exposure of the optical fibre to high-intensity femosecond pulses λ = 264 nm is presented. Different types of fibres were investigated and it was found that strong attenuation peaks (16-28 dB) can be induced in H₂-loaded fibres     

The Submarine Optical Cable of the Submarcom S 280 System

Submarine optical telecommunication cables must satisfy a large number of specific items. To comply with specifications, CDL has developed a cable structure based on high-performance optical fibers placed with slack in the grooves of a plastic rod put in the center of a very strong cable. The deep-sea cable is the basic structure for armored cables or land cables. Armor transitions are designed to minimize cable twist. The couplings are designed to give a good optical electrical and mechanical continuity between the cable and the repeaters. The deep-sea repair is designed to be achievable on a cable ship. The cables, repairs, and couplings have successfully sustained several sea trials and two experimental links are now operating. No increase of the attenuation of the optical fibers in the cable have been noticed on the 19-month old first link. The development of the S 280 cable is proceeding on the right track.     

Super-multi-fibre PLC connector utilising angled connection between PLC and tens of fibres

A novel super-multi-fibre planar lightwave circuit (PLC) connector, designed to connect tens of optical fibres and a PLC for super-multichannel PLC-based optical modules with a receptacle interface, is proposed. This connector employs an angled connection instead of a PC connection. A 0.127 mm pitch 32-fibre connector is also demonstrated, which exhibits low connection and high return losses.