Monday, 24 June 2013

Launch of O3b space constellation



An innovative new space network goes into orbit. O3b will put a series of satellites 8,000km above the Earth to provide communications to those parts of the world that have poor fibre optic infrastructure. With backing from blue chip companies such as Google, O3b believes its novel system can change the broadband experience for millions of people. The network's first four satellites will launch from French Guiana. They will ride a Soyuz rocket from the Sinnamary spaceport, with lift-off scheduled for 15:53 local time (18:53 GMT).


It will take just over two hours for the Soyuz's Fregat upper-stage to raise the satellites to their operational altitude. O3b will handle primarily voice and data traffic for mobile phone operators and internet service providers. It will pick up this traffic as the spacecraft pass overhead and then relay it to ground stations or teleports, for onward connection to global networks.


Although other satellites routinely do this, O3b is taking a markedly different approach. By flying in a Medium-Earth Orbit of 8,000km, its satellites will be a quarter of the distance from Earth as compare to traditional geostationary (GEO) telecommunications spacecraft, which sit some 36,000km above the planet. This should reduce substantially the delay, or latency of the signal as the voice or data traffic is routed via space.


"The network was designed to avoid much of the difficulty that satellite connectivity provides today which is this delay," said O3b CEO Steve Collar. "We've all been on a satellite call and you have that 600 milliseconds delay, which doesn't sound like much but it's enough to make that connection almost unusable. It's just as much of a problem on data networks. If you are on the internet and are searching for a site, it affects your behaviour if you get slow responses. You'll stop using the service. We wanted to fix those problems and the only way to fix them is to bring the satellites closer to Earth."


O3b is promising round-trip transmission time of a little more than 100 milliseconds. The satellites will operate in the high-frequency Ka-band and have the capability to deliver 10 beams, at 1.2Gbps per beam, to each of O3b's seven operational regions. The company expects to start services at the end of the year, once it gets eight spacecraft in orbit, but the intention is to put up perhaps as many as 20 eventually. It has taken about six years to put the O3b project together. Important backers include not only Google but SES.


The first four satellites are sitting atop their Soyuz rocket waiting for launch. O3b was born from founder Greg Wyler's frustration with the difficulty of connecting a modern teleco in Rwanda to the global fibre optic network, and the constraints which placed on the performance. O3b actually stands for "other three billion" - the number of people whose poor communications experience is expected to improve over the coming decade. O3b sees itself as an important agent of that change.


"There are two billion people in the world that are connected to the internet today; there are five billion who are not; and three billion who will be in the course of the next 10-15 years," said Mr Collar. "The other three billion is our target, that's who we're trying to reach, and that's where our name comes from." The Jersey, Channel Islands-based outfit has raised more than $1bn to build its space and ground infrastructure.


O3b's largest debt facility, over $0.5bn, is provided by HSBC, ING, CA-CIB and Dexia, and is underwritten by the French export credit agency, Coface. The agency is supporting three new space constellations, all of them built by Thales Alenia Space. The 700kg spacecraft,  TAS is building for O3b are based on the 24 spacecraft it has just finished for the Globalstar satellite phone network. One of the challenges of running the system is tracking platforms as they move across the sky.


"The constellation will be spread equally around the equator which means you have to pick the satellite up as it comes over the horizon and follow it to the other side; and as soon as it goes out of visibility there is already another satellite waiting to be picked up," explained Philippe Nabet, the TAS programme manager on the O3b project. "There will be three antennas at the ground stations, two to track the satellites; the third is a spare."










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