The project is concerned with the specification, development and establishment of field trials demonstrating an optically supported millimetre wave link as a final drop to the subscriber, to provide rapid and flexible deployment of broadband interactive services. It merges existing passive optical networks with a photonic technique for generation, modulation and transmission of information bearing millimetre wave signals to a hybrid fibre-radio customer access system. Two trials are proposed, working at different bit rates and based on different multiple access techniques in the uplink.
System concept and specification, including specification of interfaces to trial platform;
Realisation of first components, design of subsystem;
QPSK transmission experiment (27.98 GHz, 25 Mb/s) over 12 km standard single mode fibre and 1:8 splitting;
A first hybrid fibre-radio field experiment over a 46.2 km installed standard single mode fibre loop has been carried out between Stuttgart and Ludwigsburg in Germany (using fibre cable of Deutsche Telekom) using a 60 GHz carrier frequency and 140 Mb/s data rate.
Further project plans are:
Study and implementation of optoelectronic and electronic mm-wave components;
Realisation of field installable remote antenna unit;
Realisation of customer premises equipment;
Realisation of optical, radio and DSP subsystems for DS-SS transmission;
Field trials covering several 100 m of free space radio transmission;
Contribution to guidelines, roadmaps and standardisation.
The FRANS project will demonstrate technologies and techniques that are applicable to the provision of low-cost, tetherless, broadband customer access. The achieved results will contribute to the functional specification of the IBCN. FRANS is focused on enabling optical support for radio technologies to facilitate a rapid roll-out of IBC services before fibre is deployed to the home. The project realises a demonstration of 'Radio-frequency signals transport through optical fibres' as recommended in an ITU-R draft recommendation.
Main contributions to the programme objectives:
Hybrid fibre-radio broadband access network demonstrator, based on direct mm-wave modulation of the optical carrier.
Contribution to the programme
Demonstrates technologies for low-cost, tetherless broadband customer access.
System, network architecture and service deployment studies will lead to selection of detailed system parameters, to guide the design work and ensure optimum performance.
Two different system approaches will be realised:
A 622 Mb/s downlink with TDMA uplink of 40 Mb/s aggregate bitrate (~2 Mb/s per user), both with a millimetre wave radio part working in the 30 GHz range;
A downlink of up to 4 channels of 34 Mb/s total bitrate with millimetre wave radio interface at about 30 GHz and a CDMA uplink with 1 to 5 multiples of 2 Mb/s per user with a microwave radio part in the 2.5 GHz range.
The downlink is based on a principle developed in RACE 2005 (MODAL).
The TDMA uplink uses a different millimetre wave frequency, remote down conversion in the antenna unit and microwave transport over the PON to the central unit.
The CDMA uplink uses a microwave carrier frequency which is transmitted directly, or via a fibre optic connected remote antenna, to the central unit.
Within the extension granted following the second ACTS call, optical transport of an IF signal with local up-conversion, supported by an optically fed reference signal, will be investigated as an alternative fibre-radio hybrid solution.
Summary of Trial
The multi 34 Mb/s trial is planned as a joint trial with ATHOC, complementing the hybrid fibre-coax access of ATHOC by a fibre-radio access. The joint trial will use the same set of services (TCP/IP and native ATM applications, like VOD on consumer/medical information or teleworking) and will allow communication between the HFC and the HFR access area.
The 622 Mb/s trial is based on a passive optical network located in Lannion, France. At least two of the 16 users, which share the 622 Mb/s and are supported by the TDMA management, will be equipped with a fibre-radio link for delivery of multimedia services. The services will be provided by a local server or a distant server in Rennes via an ATM network.
Selection of modulation scheme for broadband/subcarrier multiplexed signals;
Design of highly interdependent fibre and radio links;
Realisation of multiple access uplinks for a hybrid fibre-radio network with an antenna unit of low complexity;
Ruggedised realisation of advanced subsystems for field application.
Funding SchemeCSC - Cost-sharing contracts
WC1E 7HX London
YO1 5DD York