Live Iridium Video from Arctic

Posted by Sam Churchill on

The Vanco Arctic Survey is a pioneering international scientific endeavour, likely to prove the most ambitious ever undertaken on the North Pole ice cap.

The North Pole ice cap, which floats on the Arctic Ocean, is melting at an accelerating rate. The survey will capture, for the first time, detailed information about the thickness of the ice and snow and help to determine just how long the ice cap will exist in a climate-changing world.

An ice-penetrating radar is being pulled across the ice to measure the depth of the ice under the snow. Lithium ion batteries power the sled.

But direct communications from polar expeditions have been severely restricted up until now. The only commercial satellites that work at the far North and South poles – Iridium’s LEO constellation – is limited to about 2.4Kbps.

However the expedition’s ice team is transmiting video, web cam and still image footage directly from the North Pole ice cap. They have developed a Linux-based computer that consumes only two watts and uses 6 parallel Iridium modems.

This equipment will receive, reformat, store, compress and transmit all the vital survey, image, audio and bio-telemetry data back to the UK HQ – on a live and delayed live basis. During the 120-day trek to the North Pole, the team will take around 10 million readings of the ice and snow thickness.

Web-cam footage and live telephoned commentaries, are supplimented with data generated from implanted bio-monitors. This innovative link-up between bio-monitors and state-of-the-art data transmission technology will connect researchers directly to newsrooms, websites, mobile phones and PC’s, allowing a global audience to be directly connected to what’s happening on the ice.

Current predictions for the melting of the ice cap vary wildly, from 100, to just 16 years from now. The disappearance of the permanent ice cap will cause accelerated climate change and rising sea levels, say scientists. The polar expedition hopes to get a better estimation of this change.

Meanwhile, the Argo ocean observing array last week reached its initial target of operating 3000 robotic floats worldwide. By systematically measuring the temperature and salinity to a depth of 2000m, Argo has already improved estimates and forecasts of sea level rise caused by thermal expansion and is playing a key role in improving seasonal climate forecasts and giving new insights into hurricane activity.

An international consortium manages the array of 3000 autonomous instruments that will revolutionize the collection of critical information from the upper, climatically important, layers of the worlds’ oceans. Argo deployments began in 2000 and will continue to provide about 800 floats per year (which has occurred for the past three years).

Besides float deployment, Argo has developed two separate data streams: real time and delayed mode. Real time data delivery delivers 90% of profiles to users via two global data centers, in Brest, France and Monterey, Californiax, within 24 hours.

Geostationary and near-polar orbiting meteorological/environmental satellites, including ARGOS, collect the data. What makes Argos unique is the ability to geographically locate the source of the data anywhere on the Earth utilizing the Doppler effect. It is often used to track both sea and land animals.

At the poles, the satellites see each transmitter on every pass, a total of roughly 28 times a day for two satellites or 56 for 4 satellites. The window during which the satellite can receive messages from the transmitter lasts about 10 minutes on average.

Marine data are also collected through the International Maritime Mobile Service and through INMARSAT with data distribution via meteorological satellites. Equatorial Low Earth Orbits are a subset of LEO. These orbits, with low inclination to the Equator, allow rapid revisit times. Orbits with a high inclination angle are usually called polar orbits.

Iridium (basically a muni Wi-Fi net in the sky), is now selecting their next generation of LEO sat phone satellite platforms, as is bent-pipe advocate GlobalStar (with Alenia Space).

Orbital Sciences designs, manufactures and supports Orbcom LEO and GEO satellites. During the last five years, they have deployed 46 satellites; with an additional 15 satellites under contract. ORBCOMM operates twenty-nine satellites in six orbital planes that provide worldwide coverage, but does not offer voice, since it’s a store and forward platform.

Sirius Satellite uses Highly Elliptical Orbit (HEO) to keep two satellites positioned above North America while another satellite quickly sweeps through the southern part of its 24-hour orbit. Molniya constellations (Java applet), keep lots of balls in the air.

Three Russian HEO satellites and one GEO over the United States watch U.S. ICBM bases continuously, with apogees of 39,700 km and perigees of 600 km, inclined 63 degrees. Boeing’s Trumpet signals intelligence satellites, in Molniya orbit over Russia, monitors Soviet communications and missile tests with an antenna of the size of “two football fields”.

Boeing’s TDRS, in GEO space, uses a pair of 15-foot, flexible mesh antennas that can simultaneously transmit and receive at S-band and either Ku or Ka-band. Receive data rates are 300 Mbps at Ku and Ka-band, and 6 Mbps at S-band.

But what about Medium Earth Orbit (MEO)? The intermediate circular orbit was proposed by satellite providers like Craig McCaw’s ICO. Now ICO is developing an advanced hybrid system, combining both satellite and terrestrial communications capabilities.

But could phased array antennas, similar to Cisco’s Navini, provide beamformed Mobile WiMAX from MEO space? That would be quite a challenge. Perhaps China, India, South Korea or Japan will get there first. Sounds like a job for the United Nations. Or Google.

Just in time to provide live television feeds to citizens living on the North Pole.

The New Frontier.

Posted by Sam Churchill on Saturday, November 3rd, 2007 at 11:32 pm .

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