London - An international group of communications companies and research institutes plans to develop a network that will use balloonlike airships to bring broadband communications service to remote rural areas and even to moving trains.

The team's High Altitude Platforms (HAPs) will be permanently located in the sky at an altitude of 20 km. The aim is to provide access at 120 Mbits/second anywhere within an HAP's 60-km-diameter coverage area. The team said its approach will be cheaper and more efficient than cable- or satellite-based delivery because the HAPs do not require underground cabling or masts.

The Capanina group, funded by the European Union, includes researchers experienced in both millimeter-wave and free- space optics technologies. The latter will be used to create interplatform links to supplement millimeter-wave-band communications for back-haul traffic. The effort is part of a larger project within the EU's Sixth Framework Programme (http://europa.eu.int/comm/research/ fp6/index_en.html), aimed at providing broadband services.

Capanina will be led by the University of York, England. Other participants include BT Exact Technologies and SkyLinc Ltd. from the United Kingdom; Contraves Space AG and the Centre Suisse d'Electronique et de Microtechnique in Switzerland; Carlo Gavazzi Space and EuroConcepts from Italy; as well as the Japanese Communications Research Laboratory, which is involved in a related project funded by the Japanese government.

Initial funding is about $6.8 million, the bulk of it coming from the EU. The project builds on another EU program that showed the enormous potential of broadband from HAPs and developed an outline system design.

Researchers at York will investigate the most effective way to operate wireless links via HAPs, including propagation and resource management. The team will develop HAP-based systems that can use the spectrum efficiently to reach all areas, including steerable antennas. The other partners will handle equipment for trials, business models and free-space optics. The first goal is to deliver broadband to rural areas across Europe within four years. Ultimately, the team will look at delivering high-bit-rate connections to moving trains.