England, UK, April 24, 2005 -- The test was conducted
under the IST project Capanina, now studying the use of wireless and optical
broadband technologies from high-altitude platforms (HAPs). A typical HAP is an
airship that floats at an altitude of 20 km. The test called on equipment
operating in the 31/28 GHz millimetre-wave band. These frequencies are much
higher than today’s fixed wireless access links and enable higher data rates,
but their signals can for example be affected by rain.
According to project contact Alan Gobbi, ‘stratospheric broadband’ fills the gap
between satellite and terrestrial wireless technologies. “Place airships fitted
with these communications technologies every 60 km, in a grid configuration, and
you would have complete coverage of everywhere on the ground. You could offer
everything from mobile phone calls to high-definition TV.”
The project’s target data rate is 120 Mbits/sec, currently much faster than the
fastest ADSL (Asymmetric Digital Subscriber Line) connection. In the trial, the
partners even achieved 270 Mbits/sec using a free-space optical link.
If ADSL speeds cannot keep pace with evolving multimedia applications, HAPs
could step in. “These platforms could provide low-cost broadband for suburban
and rural areas where there are no alternatives,” says Gobbi. “But we are not
saying HAP-based broadband will replace ADSL in city centres.”
Besides offering wide-area coverage, this technology has another major benefit.
“The cost of establishing an HAP-related communications device is estimated to
be one-tenth the cost of a satellite. In terms of a satellite’s ability to serve
multiple users on the ground with broadband, HAPs can support one thousand times
more people,” says Gobbi. “They could offer cheaper solutions for medium-density
areas, filling the gap between cables/fibre for high-density cities and
satellite for sparsely populated areas.”
HAP technology could even serve passengers on a train travelling up to 300
km/hour. It would involve steerable antennas, on the airship and vehicle, with
sophisticated beam control. The project’s partners are studying related issues,
such as the need for line-of-sight communication at these high frequencies and
signal break-up due to tunnels.
Two more HAP trials are planned. In August 2005, an untethered balloon will be
flown in the lower end of the stratosphere over Sweden, testing HAP performance
in extreme cold and the effect of a balloon movement. In the summer of 2006, the
partners will team up with the National Institute of Information and
Communication Technology of Japan for a global HAP trial involving solar-powered
unmanned aircraft.
“Our trials proved the concept of aerial platforms delivering reliable optical
high-speed communications,” says Gobbi. He believes broadband delivered from
HAPs to fixed users could be a reality within three to five years, with services
to travelling users coming two years later. In particular HAPs could provide
communications for disaster relief and events.
But he recognises this will require more industrial effort, especially for
setting up the infrastructure: “The partners have their own exploitation plan.
If there are gaps, we will link up with other organisations and service
providers.” For an innovative follow-up project, Gobbi would like to study the
delivery from airships of WiMAX, the increasingly popular broadband wireless
standard.
Please mention IST Results as the source of this story and, if publishing
online, please hyperlink to: http://istresults.cordis.lu/
Contact:
Tara Morris, +32-2-2861985
Alan Gobbi
York Electronics Centre
Vhttp://www.capanina.org/
+44-1904-432323
News Source: PRWEB