Broadband To Hit The South Pole

Albanach writes: "According to this story from the BBC bids are being invited to lay a fibre-optic cable some 1600 kilometres over polar ice, linking researchers at the South Pole with the rest of the planet. Currently, researcher's communications rely upon older satellites that have drifted from their geostationary orbits into ones that are now at least partly visible from the pole. The new cable will be laid on top of the 4km ice cap, and will have to cope with repeated freezing and stretching as the ice moves."

Comments

Why not just use Iridium?

[Animats]

Iridium is back up and running, covers the entire planet (the satellites are in low polar orbits) and the U.S. Government has a bulk buy deal on Iridium satellite minutes. (DoD now owns part of the system, having bought in after the bankruptcy.)

Not necessarily

[multipartmixed]

Instead of laying the cable in a straight line, you lay it in S-shapes. Big S-shapes. That way, there's LOTS of slack, say 500% slack, for the ice sheet movement.

Of course, you have to use a fairly flexible conduit -- copper piping should do nicely, as long as you can figure out how to make sure it doesn't kink too badly on compression. The S-shapes, again, would help, but a better material would be even better. Maybe copper line with a thick kevlar braid, along the lines of the braid used in a Chinese finger puzzle/trap.

The Canadian Armed Forces has to recalibrate their microwave dishes every eight years or so up north for CFS Alert on Elsmere Island, because the ice moves. That gets expensive in the long run (Snowcats, helicopters, men), and would be MUCH worse for Antarctica.

And finally, finding a break in the fiber wouldn't be too hard, ever heard of a time-delay reflectometer?

Issues Point by Point

[maggard]

1. Satellite

   Lovely solution, just one problem: They don't stay put.

   Sure over the equator they can orbit at the same rate the planet rotates and so appear "fixed" but that only works over that narrow ecliptic. Instead to cover extreme N. & S. latitudes one needs sats on a much more inclined orbit and then they're out of sight much of the time, a dozen or so would be required to provide continuous coverage. That means a couple of expensive launches, a serious of expensive sats, and of course their own-going management (course-corrections, problem resolution, etc.)

2. Radio Repeaters

   Why not build a series of microwave repeaters or such, bring the cable to the shore then broadcast the rest of the way? A couple of reasons:

   1. Putting in place that many repeater stations across the Antarctic would be difficult. They'd need to be tall, durable (in super-cold weather), well-anchored, and able to compensate for slowly moving stations.
   2. Getting back to them to fix any problems would be well nigh impossible much of the year so lots of redundancy, increased complexity, etc.
   3. Where's the power to come from? There isn't any local grid to plug in to and as the Canadians & Siberians will attest running long power lines across extreme latitudes is difficult (no grounding, lots of electromagnetic effects from aural storms, etc.) Solar won't work for a few months a year plus there's the buildup problem, burning hydrocarbons wouldn't be allowed plus would require regular refueling, and radiothermal seems very unlikely.

3. Fiberoptic Cable

   Yes fiber isn't the most robust material on its own. On the other hand it can be clad in all sorts of super-durable materials to protect it.

   To protect from stretching the fiber might be coiled inside an outer cladding so it's 2x or 3x as long as required. Or it could be threaded through an outer cladding (think 'garden hose') so it can slide back and forth under slight tension between 1km "reservoir" loops.

   Of course there's still the problem of powering the repeaters, but then that's why this contract is out there: To get folks interested in solving the problem.

Hmm, what would the Thunderbirds have done?