The first phone system in space was completed last week, writes Tim Phillips
At 1.29am last Saturday, Arianespace flight 105 blasted off from the European spaceport at Kourou, French Guyana. On board was a 2 000kg satellite destined for a 15-year mission 35 580km above the equator, where it completes man’s first telephone system built in space.
After launch, Inmarsat’s satellite control centre in London sent a message to the satellite, firing its 16 thrusters to manoeuvre it into a geostationary orbit, floating over one spot on Earth. Another message extended its 30m2 of solar panels, generating enough electricity to keep it operational.
The satellite is the fifth Inmarsat-3, the culmination of a $3-billion project funded by 1 200 companies and 80 member countries. The four already launched are equally spaced around the equator, high enough to cover 98% of the world’s land mass (only the poles escape). The fifth satellite is insurance: if one of the existing satellites fails, it can plug the gap.
Westerners who don’t make telephone calls from war zones, ships or deserts — that is, most of us — will have little to do with Inmarsat. But for the three billion people on the planet who live in areas too remote to be on the telephone network, Inmarsat and its competitors offer a point of entry to the information age.
Although the smallest telephone that can beam a signal up to Inmarsat-3 weighs 2kg, is the size of a laptop computer and costs $3 000, they are turning up in the strangest places. In 11 villages in northern India, where there’s not only no telephone network but no electricity, solar-powered “phone boxes” let villagers make government-subsidised calls for 14 rupees (about R1) a minute. There are similar schemes in Ghana, China, and South Africa.
Three billion dollars is a high price to pay for a telephone network, but Inmarsat’s system is, in satellite terms, relatively cheap.
Raising money to add new commercial satellites to the 3 500 already in orbit doesn’t seem to be a problem. In the next week, they will be joined by two more examples of satellite systems — known as “constellations” — that could change the way we use cellphones in the next two years.
First, Iridium — a subsidiary of Motorola — will launch five more satellites from Vandenberg United States Air Force base in California. The Iridium constellation will be made up of 66 equally spaced satellites only 660km above the earth. Within a week, Globalstar, part-owned by cellphone network supplier Vodafone, will launch the first four of its 56 satellites from Cape Canaveral. Globalstar’s network, like Iridium, will float relatively low: only 1 600km up.
The advantage, says Globalstar representative John Cunningham, is that low-flying satellites mean no awkward pauses in messages; it takes half-a-second at the speed of light to make the round trip to Inmarsat-3. It also means that handsets can be smaller.
Within the next two years, says Cunningham, dual-mode telephones, which use existing cellular networks and switch to satellite systems when they need to, will cost around R1 600. “Calls will cost between R5 and R7,50 a minute, and we will handle 65 000 simultaneous calls. And there’s not much to go wrong with our satellites.”
Despite a $5-billion investment, Globalstar’s satellites function in a straightforward fashion, simply reflecting calls back to a ground station, where they enter the terrestrial network. Iridium, by contrast, has satellites that can “hand- off” messages, looping them through space to their destination: the result is a smaller delay, but there is more to go wrong with the network.
If Inmarsat is today’s technology, and Iridium and Globalstar next year’s technology, then the 288-satellite constellation planned by Teledesic is the next century’s technology. Teledesic plans an “Internet in the sky”, offering 64Mbits/sec downloads (about 2 000 times the speed of a standard modem) to anyone with a 50cm satellite dish. The satellites are scheduled to launch in 2001, when they will orbit at a height of less than 1 600km above our heads, pinging data backwards and forwards among satellites using high-power laser beams.
This isn’t James Bond, claims Teledesic president Russell Daggatt. “We’re using only technology that’s been proven in space or on the ground,” he says. The bill? A cool $9-billion.
That Teledesic is given credibility is due perhaps to one of its financial backers: a certain Bill Gates.
Commercial satellite companies are speculating more than $12-billion this year alone on a market that barely exists, driven by the belief they can literally network the world.