UK project seeks to build multiple-hop antenna system

Entire communities may soon be networked by meshes of radio transmissions that will carry much more data than existing wired services. A new kind of antenna will act as a relay node, forwarding signals through the air to link eventually with the public internet or private networks.

The project depends upon perfecting the multiple-input-multiple-output (MIMO) antennas and the algorithms and protocols that will maximise their efficiency. ‘Essentially MIMOs behave like a lot of mini antennas in one,’ said research co-ordinator Prof Kin Leung of Imperial College London. Industrial collaborators include Lucent Technologies, ETH Zurich, Intel, CEFRIEL, Intracom and Telefonica.

The aim is to design a system where signals hop from one antenna to the next, following reconfigurable routes that optimise the network. ‘It’s relatively challenging to build a multiple hop system,’ said Leung. ‘The hops could be as short as 100m or as long as a few kilometres. In rural areas directional antennae with line of sight could cover even greater distances.’

The researchers are not yet targeting a specific frequency band although the technology may be best suited for the lower end of the available spectrum, perhaps around 1900mHz used by 3G. ‘We are still looking at it as a generic issue,’ said Leung, whose programme has two years to run.

Present wired technologies such as ADSL and T1 lines can carry only a limited amount of data compared to the planned wireless system. T1 is rated at 1.544 Mb/sec and Leung’s team is to exceed that capacity several times over. Although optical fibres already exceed these speeds they are relatively expensive to install. The team hopes that wireless will combine high speed and low cost.

‘The internet has become an integral part of our daily life and continues to grow. Instead of relying on traditional wired lines, we need to explore alternative, efficient technologies to connect users in homes and offices. We hope to see this technology in use within the next five to 10 years,’ he added.