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Product Overview
Fibre-optics can be seen as a replacement for copper wire systems for communication and signal transmission. It can span long distances and provide the backbone for many network systems. Other systems users include television services, network on university campuses, between office buildings, industrial plants and electric utility companies.
Lately we see the new telecoms providers as well as Telkom installing large infrastructure to carry fibre networks all over our country. These networks have a special fibre deployment method called blown fibre. This is when the fibre cores are blown into the pipes as needed.
Fibre-Optic Cables – Multi-mode
Multi-mode fibre has a large core, up to 50 microns in diameter. As a result, some of the light rays that make up the digital pulse may travel a direct route, whereas others zigzag a they bounce off the cladding. These alternative pathways cause the different groupings of light rays, referred to as modes, to arrive separately at a receiving point. The pulse, an aggregate of different modes, begins to spread out, losing its well-defined shape. The need to leave spacing between pulses to prevent overlapping limits bandwidth, that is, the amount of information that can be sent. Consequently, this type of fibre is best suited for transmission over shorter distances, up to 12km.
Fibre-Optic Cables – Single–Mode
Single-mode fibre has a narrow core (8 microns or less) and the index of refraction between the core and the cladding changes less than it does for multi-mode fibre. Light thus travels parallel to the axis, creating very low pulse dispersion.
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