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Although fixed wireless access has been heralded as an alternative broadband access technology for many years, when the UK government attempted to auction this spectrum at the beginning of the year, it was more or less a complete flop – with many areas with spectrum available receiving no interest at all. However, says Will Dobbie formerly of BT Laboratories, “Mesh radio – a different type of broadband fixed wireless – is a new technology that could make fixed wireless access practical for the first time.” The problem with the existing broadband fixed wireless access solution of LMDS (local multipoint distribution), he says, is that this technology requires: base stations, high power amplifiers and sectorised antennas on towers in locations carefully selected for coverage. It is because of these shortcomings, says Dobbie, that LMDS could only ever be comparable in cost to cable or ADSL in densely populated areas – and then only if a mass-market develops. But this is unlikely, he says, because of LMDS’ inefficient use of spectrum and the relatively poor line-of-site coverage. In fact, Dobbie believes that LMDS is only ever likely to be used as a short-term expedient for a limited number of business applications. However, according to Dobbie, mesh radio has none of these shortcomings. “It uses point-to-point links between nodes mounted on customer's homes, which avoids the cost of expensive base stations. Each ‘node’ contains a number of remote-controlled directional antennas, which allows low power amplifiers to be used. Customers are then served via a series of short links that avoid obstructions such as tall buildings, which give a higher coverage than for LMDS,” he says. There are also other advantages with mesh radio. The network grows as demand increases and can self-heal by re-routing if an intermediate node fails; it can also connect to an existing fibre point, for example, one feeding a corporate customer. The cost per customer could therefore be significantly lower than for LMDS. These factors reduce the up-front investment costs and make it feasible to provide services in suburban or semi-rural areas with low subscriber densities where cable and ADSL are unlikely to be available. Although ADSL avoids the cost of digging up roads, the disadvantage is that the bit rate reduces with line length and a high percentage of customers will not be able to have the 5Mbps or so needed for high quality digital TV. While mesh radio should not be able to compete directly with cable and DSL in urban areas, if the current slow progress with DSL continues – and cable is not opened up – it could prove to be an attractive option for smaller service providers. However, mesh radio is definitely competitive in urban areas of those countries without a developed communications infrastructure. There is, therefore, a huge potential market for the technology. The problem Cambridge-based Radiant Networks is developing a proprietary mesh radio system for business customers and is planning trials soon. However, a number of technical and commercial issues need to be addressed before mesh radio is ready for a mass-market implementation. Low cost, unobtrusive mesh radio nodes are required and they are more likely to be developed if the consumer electronics industry works towards a common standard. The good news, however, is that plans for a new industry group aimed at defining an interoperability standard are now well advanced. It has also been agreed that a patent application describing a way of reducing the size of the nodes will be made available to the group when it is in the public domain. The first task, however, is to lobby the UK regulator for 1GHz of dedicated spectrum in the 40GHz band and for an appropriate regulatory regime. The UK represents a good test case because the government is actively seeking a means of using radio for broadband IMS (Interactive Multimedia Services). A successful implementation of mesh radio in the UK would also set a viable precedent that could be followed in many other parts of the world. The 40GHz band is available worldwide and a 1GHz allocation would still leave up to 2GHz available for other applications. The UK government has the power to create an environment where silicon vendors and manufacturers can invest with the confidence that a mesh radio market will precipitate. Mesh radio is completely new and it can be introduced independently of any existing network or operator. The government could therefore introduce a third means of delivering broadband IMS that is open to all service providers as was intended for ADSL. From analogue to digital TV However, of more significance is that the UK government could also significantly speed up the UK's the transition to digital TV – bringing forward the date for further UMTS spectrum auctions. Dobbie recommends that the government revitalises the consultation process with a proposal for an auction of dedicated spectrum licenses to network providers. The recipients would be allowed to serve corporate customers and provide UMTS backhaul services, but they would be prohibited from selling services directly, and from discriminating between service providers. The revenue, says Dobbie, should be used to partially subsidise the: · Provision of set-top-boxes and integrated TV's capable of receiving free-to-air TV delivered via a range of broadband IMS networks Dobbie opines that this approach could bring huge potential benefits to the UK economy, but only if the government acts promptly and is prepared to weather the criticism that will inevitably follow from those operators with vested interests in core / access networks and systems. It is therefore essential for those who stand to gain most from mesh radio – the service providers, potential new broadband network and consumer electronics companies – to support a submission to the government. For more information on how to do this, go to |
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