EoW January 2008

english

A novel aerial air-blown solution for FTTH networks using pre-terminated fibre and micro cables By Anders Björk, Mårten Björs and Peter Lo Curzio, of Ericsson Network Technologies AB, Hudiksvall, Sweden; and Bill McGavin, Ericsson Communications Ltd, Auckland, New Zealand

1. Introduction The advent of broadband technology delivering triple play services has revolu- tionised the way of modern business and home entertainment. To the communities that have these service facilities already, such services are now just a way of life. Amajor reason why fibre-based broadband is not more universal is the high cost of the civil works for underground building. Heavily built-up areas and areas that are located on hard rock terrain are typical areas that operators try to avoid in their rollout of broadband services. In such areas aerial solutions can be an option, especially in cases where an existing aerial infrastructure already is in place, eg over- head power distribution or telephony. Air-blown fibre and micro cables have been proven to be very efficient for fibre access network applications such as Fibre To The Home (FTTH). When using pre-terminated fibre, the installation time can be kept to a minimum compared with conventional cabling techniques. Furthermore, the air-blown technique enables a ‘dynamic’ network where fibres can be quickly and easily added, removed, replaced or re- routed without expensive civil works. Aerial air-blown fibre installations have suffered in the past with regard to the aesthetics and practical installation. Modern advances in fibre cable design, see [3] and [4] , and installation practices have totally revolutionised aerial installation which will be discussed in this paper. We propose a novel technique for aerial installation of fibre using air-blown techniques describing these advances in both design and installation techniques.

Figure 1 : Pole line with distribution terminal closures on each 5 th pole ▲

2. Solution Description The basic aerial air-blown system design is the same as for a traditionally underground system. However, some new products had to be developed, see section 3 . The solution is based on self-supporting ducts combining pre-terminated air- blown fibre units as well as air-blown micro cables. The technology is unique in many ways: a single duct assembly can be used for both the distribution and drop sections of a FTTH network. By sharing the same infrastructure for distribution cables and drop cables in a fibre access installation, considerable cost savings can be made. The installation cost for a single assembly is obviously lower than installing separate cables for feeder and drop sections of the network in parallel •

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it also fully utilises the benefits of incremental fibre deployment, allowing new fibre to be installed quickly and at low cost when needed. Thus, it is possible to postpone costly investment in fibre for the future – ‘pay as you grow’ the solution is equally suitable for Passive Optical Networks (PON) as well as Point To Point Networks (P2P). In fact, both topologies can share the same physical infrastructure. A PON network can be upgraded to a P2P network without additional investment in ducts a general requirement for all products in this concept is small dimensions and low visual impact. The visual impact of aerial pollution is a key factor in the acceptance or rejectionof such solutions by the community. Communities no longer allow installations that impact on their visual rights

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EuroWire – January 2008