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Billions and billions of dollars in orbit: global links for mobile
phones
Matthew James
Science, Technology, Environment and Resources Group
A New Era Begins
By the middle of 1997, the first of a new generation of mobile communications
satellites will have been launched into low Earth orbit. By the end of
the decade, some of these will offer individuals a global telephone service.
While users will be able to send and receive calls no matter where they
are, they face a variety of handset types and capabilities as the systems
become established. Telecommunications analysts do not expect all of the
rival systems to survive in the long term. They argue that high costs
for both handsets and use, poor voice quality and poor indoor penetration
will hamper market expansion.
An aspect of concern to existing telecommunications carriers is that
the new satellite systems may completely bypass existing ground networks,
controls and charges. Some governments have acted to protect incumbent
carriers while others intend to make no restrictions at all.
GEO vs LEO Satellites
Until recently, only satellites in high geostationary Earth orbits (GEOs)
were available for communications links. Since they remain in the same
position relative to ground stations, each satellite can relay signals
to one-third of the globe. This is the basis of the Intelsat and Inmarsat
fixed systems that have served most countries for the last three decades.
But orbital slots are crowded, and GEO systems have other problems because
of their height: they require high power for transmission and signal delay
makes voice traffic, in particular, somewhat uncomfortable to users.
Such problems do not affect low Earth orbit satellites (LEOs). However,
LEO satellites can only 'see' a smaller proportion of the ground as they
rapidly move across it, so more satellites are needed to cover the globe
and handset signals must pass from satellite to satellite as they orbit.
Nonetheless, there are a number of schemes to establish mobile telephone
satellites in geostationary orbit, particularly to serve Africa, India
and Asia. Among these are the Asia Pacific Mobile Telecommunications single
spacecraft scheme, the Asia Cellular's Garuda two Satellite Scheme (under
construction), and the Afro-Asian Satellite Communications two Agrani
craft due for launch this year. They may offer thousands of simultaneous
telephone calls from dual-mode, hand-held phones.
Carrier Strategies
Australia is to have an open market from July 1997, and the existing
carriers Telstra, Optus, Vodafone and other parties are assessing their
options with global systems. Vodafone has links through its British parent
to the Globalstar system. Local service provider Spectrum Network
Systems has a stake in the Ellipso project. Iridium has
a South Pacific office in Sydney, and Telstra provides Inmarsat
access.
While Iridium estimates the potential market for mobile users
at anywhere from 5 to 15 million worldwide, best estimates for Australian
usage seem rather small. By the year 2000, operating systems should provide
some 3 000 voice circuits over Australia. By 2005, this may rise to 200
000 circuits, serving one million users.
Satellite access gateway franchises offer carriers one means of involvement.
These connect the satellite network to the ground network and also involve
service providers. However, some of the proposed systems do not regard
Australia as an early market. A listing follows of many proposals.
Iridium
The Iridium satellite system is the most advanced so far and will involve
a constellation of 66 spacecraft. Under a US$2.6 billion finance package,
Iridium operators Motorola, Lockheed-Martin and others secured United
States Federal Communications Commission (FCC) approval, but expect to
need US$4.7 billion by 1999. For Australian users, Iridium should be compatible
with the GSM phone standard, allowing one US$2 500 handset to access both
local systems and satellites when operations begin in 1998.
Globalstar
Globalstar has raised most of the US$2 billion that it requires to launch
in 1998 and 1999, and has received FCC approval. Loral, Qualcomm, Air
Touch and Vodafone are major investors in a 48 satellite scheme. Globalstar
GSM handsets will have two modes and cost from US$500 to $750.
Odyssey
Led by TRW and Teleglobe of Canada, Odyssey involves a US$2.5 billion
contract for 12 satellites and ground control
facilities. Odyssey has FCC approval to utilise an intermediate circular
orbit patented by TRW to begin in 2000. Cost of handsets may be US$500.
ICO-InmarsatP-Project 21
ICO Global Communications also proposes a medium earth orbit 10 satellite
system worth US$2.8 billion. Hughes as co-investor with Inmarsat, has
disputed TRW's patent claim. ICO handsets may cost US$1 000 each.
Constellation Communications
This 46 satellite Aries-ECCO system has been costed at US$1.7 billion.
The FCC has refused to approve the scheme so far.
Ellipso
Mobile Communications Holdings proposes a US$850 million 16 satellite
system. Handsets may cost US$800 or less, but the FCC has so far refused
approval.
Broadband Systems
With backing from Microsoft, Teledesic emphasises data and Internet
usage through a colossal 840 satellite system. Pending FCC approval, Teledesic
aims to provide high capacity data circuits to uncabled areas, commencing
in 2002. Other smaller data ventures include Astrolink, Galaxy Spaceway,
GE*Star, SkyBridge, VoiceSpan, Morning Star, CyberStar and Sativod. Other
types will surely follow.
Orbcomm
Orbital Sciences and Teleglobe Canada together operate Orbcomm's twin
satellite system providing real-time messaging to users on the ground.
Orbcomm plans 34 satellites in all.
Celsat
A proposed US$500 million system of three satellites is slated to begin
in 2000.
Optus
Australia's Optus B3 satellite was the first in the world to offer a
mobile service. This capability only covers the Australasian region. Optus
has 25,000 users each with $6 000 ground units.
(See Research Note 22, 1996 for Asian Satellites Broadcasting PayTV
to Australia).
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