More efficient optical networks

The radio-spectrum band at 60 GHz is licence-free, and offers reasonably large bandwidth for certain applications. In such a context, several ultra-broadband standards have been defined for wireless personal area networks.

Yet the optical fibre used to carry such networks leaves unused capacity. The EU-funded FIRMWARE (Multimode fiber radio technology for cost-efficient indoor mm-wave remote antenna systems) project aimed to develop technologies to utilise this for indoor networks. The research focused on a new photonic array receiver antenna. The purpose was to achieve fast optical networks over indoor distances up to 100 m. Such networks were intended to be low-cost and safe with a low-carbon footprint. Work involved re-purposing a particular standard optical fibre for wireless transmission.

Stages included a proof-of-concept experiment using a radio over fibre scheme, which addressed performance limitations. The resulting transmission of 3.8 Gb/s exceeded the target.

Researchers proposed a converged fibre-wireless network structure, expected to support various protocols. The idea was tested using E-PON data where E-PON refers to Ethernet passive optical network.

The group designed and built suitable low-cost millimetre-wave antennas. Another plus was the use of environmentally friendly materials.

Work produced a new, spectrally efficient, division multiplexing scheme, based on radio-over-fibre technology. The scheme addressed next-generation wireless data traffic demands.

The team also designed a network topology utilising single mode fibre to multimode fibre feeds. Further proof-of-concept experiments achieved 5.0 Gb/s.

Lastly, the consortium addressed a PON/mm-wave converged topology. Experiments demonstrated a fast transmission rate of over 1 km.

The project's dissemination and knowledge-transfer work involved a university poster-day, a school open day, and public events. An example of the latter included project presentations to Britain's House of Parliament, and a panel of expert judges.

The FIRMWARE project achieved its goal of developing technologies that maximise the utility of optical networks. The work may mean faster computer networks, and more environmentally friendly technologies.