Introduction

In recent years it has become apparent that fiber optics are steadily replacing copper wire as an appropriate means of communication signal transmission. They span the long distances between local phone systems as well as providing the backbone for many network systems. Other system users include cable television services, university campuses, office buildings, industrial plants, and electric utility companies.

A fiber optic system is similar to the copper wire system that fiber optics is replacing. The difference is that fiber optics use light pulses to transmit information down fiber lines instead of using electronic pulses to transmit information down copper lines. Looking at the components in a fiber optic chain will give a better understanding of how the system works in conjunction with wire based systems.

At one end of the system is a transmitter. This is the place of origin for information coming on to fiber optic lines. The transmitter accepts coded electronic pulse information coming from copper wire. It then processes and translates that information into equivalently coded light pulses. A light-emitting diode (LED) or an injection-laser diode (ILD) can be used for generating the light pulses. Using a lens, the light pulses are funneled into the fiber optic medium where they transmit themselves down the line.

Think of a fiber cable in terms of very long cardboard roll (from the inside roll of paper towel) that is coated with a mirror. If you shine a flashlight in one you can see light at the far end - even if bent the roll around a corner.

Light pulses move easily down the fiber-optic line because of a principle known as total internal reflection. "This principle of total internal reflection states that when the angle of incidence exceeds a critical value, light cannot get out of the glass; instead, the light bounces back in. When this principle is applied to the construction of the fiber optic strand, it is possible to transmit information down fiber lines in the form of light pulses.

Broadly, the fiber optic cables can be categorised into 5 main types in accordance with installation requirements. At OPCOM, we manufacture indoor and slotted core fiber optic cables.

Aerial Cable

Aerial Cable is designed with integral bearer for installation on utility poles of an optical cable communication network. The slotted core cable design is available in loose fiber cable (up to 24 loose fibers), four fiber ribbon cable (4 to 96 fibers) and eight fiber ribbon cable (104 to 192 fibers). The design is lightweight and flexible and able to withstand normal installation forces of strain, crush, bend and twist. The aerial cable also comes with corrugated steel tape armoring providing good protection against rodents yet allows the cable to retain outstanding flexibility for easy installation.

All Dielectric Self Supporting (ADSS) Cable

All Dielectric Self Supporting (ADSS) cable is designed for installation on poles with maximum span of 100 meters. It can be supplied with loose and ribbon fiber or both. The aramide yarn strength member and the radial shape of the slotted core profile provide an effective protection against tension and radial forces applied by the cable fittings. Being completely dielectric, the cable can be installed parallel with power lines.

Duct Cable

Duct Cable is designed to be pulled into ducts in service ducts of an optical cable communication network. Its non-metallic characteristic enables it to be installed in an environment where there is electrical interference, for example alongside power lines. The slotted core cable design is available in loose fiber cable (up to 24 loose fibers), four fiber ribbon cable (4 to 96 fibers) and eight fiber ribbon cable (104 to 192 fibers). The design is lightweight and flexible and able to withstand normal installation forces of strain, crush, bend and twist.

Direct Burial Cable

Direct Burial Cable is designed to be placed directly under the ground either by trenching or ploughing. The metallic cable is armored with corrugated steel tape that provides good protection against rodents and allows the cable to retain outstanding flexibility for easy installation. The slotted core cable design is available in loose fiber cable (up to 24 loose fibers), four fiber ribbon cable (4 to 96 fibers) and eight fiber ribbon cable (104 to 192 fibers).

Anti-Rodent Cable

For effective anti-rodent, a layer of corrugated steel tape is formed in between two polyethylene jackets. For non-metallic cables, additional nylon jacket can be extruded over the outer polyethylene jacket to provide additional protection. The slotted core cable design is available in loose fiber cable (up to 24 loose fibers), four fiber ribbon cable (4 to 96 fibers) and eight fiber ribbon cable (104 to 192 fibers).

Indoor Cable

Simplex or Duplex Design
Both designs are flexible, non-gel filled cable for use in telecommunication stations for interconnection between the optical line system and the fiber distribution frame. It is also suitable for data networks. The sheath is made of PVC that has good tensile strength and tear resistance. The cable can be terminated with a wide variety of connectors. Simplex design is supplied with one tight buffered fiber (in single-mode and/or multi-mode) whereas Duplex Design is supplied with two tight buffered fibers, single-mode or multi-mode.

Distribution Design
This design is flexible, non-gel filled and lightweight for indoor use and is well suited for local area networks (LAN). It is also ideal for use where space is limited. It is completely non-metallic and the outer sheath is made of PVC, supplied with 0.9mm tight-buffered fiber (in single-mode and/or multi-mode). The cable can be terminated with a wide range of connectors.

Breakout Cable Design
This design is flexible, flame-retardant, non-gel filled cable used in telecommunication stations for interconnection between the optical line system and the fiber distribution frame. It is also suitable for data networks. The sheaths are made of flame-retardant PVC that has a very good tensile strength and tear resistance. It can be supplied with up to 24 tight buffered fibers (in a single mode and/or multi-mode). This cable can be terminated with a wide variety of connectors.