Fibre optic backbones are very often chosen for cost-effective wide-area traffic monitoring systems, for example in the USA, the UK, the Netherlands, Malaysia, Australia, and New Zealand. The rising use of video for highway applications will increase the use of fibre-based solutions. At present, fibre-optic networks integrate video cameras, data transmission, monitoring facilities, and software. The next stage should be to integrate the various traffic systems that would benefit from interactive traffic flow: airports, light rail, ports, inland waterways, and roads. This article discusses the use of minimum fibres and maximum information flow through those fibres. Fibre optics still faces the challenge that analogue transmission equipment is still substantially less expensive than fully functional non-compressed digital solutions. Certain construction rules are needed for an adequate fibre optic system. Equipment should use the best possible design and manufacturing standards. Noise, including video interference and laser interference, is the major factor limiting picture quality. Laser interference problems can be overcome by using wavelength-controlled lasers with appropriate wavelength spacing. Use of shared fibres or two directions on the same system requires isolation methods.
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