By James Careless

They are the "ends of the earth" as far as the satellite ground station business is concerned: those regional outposts in remote, often extreme conditions. Yet these outposts are as vital to the people they serve as light, heat and water. Here is a look at some of the toughest ground station locations on the planet.

South Pole Satellites: It’s Cold Down Here

When one thinks of regional outposts, extreme weather is the first challenge to be tackled: everything from sub-zero blizzards to searing heat and humidity. Well, since it is winter in North America, let’s talk cold. Real cold, as in Antarctica.

Down at the bottom of the planet, the National Science Foundation’s (NSF) U.S. Antarctic Program (USAP) operates three research posts, each with its own satellite downlink. The largest NSF base is McMurdo Station. Located along the coastline "under" New Zealand, it holds about 1,000 people during the southern summer, and about 200 during the winter. Average mean temperature is a chilling -56 degrees F, although during December and January, summer temperatures can climb as high as 50 degrees F. Meanwhile, the Amundsen-Scott South Pole Station is based right at the South Pole. Summer population is about 225 and the winter population is about 50. Finally, the smallest research station is Palmer Station, located on the Antarctic Peninsula, "under" South America. Forty-five people live and work there year-round.

Beyond cold, Antarctic earth stations have to cope with the relative lack of dedicated in-orbit satellites. After all, there is not enough business down there to justify launching dedicated spacecraft. As a result, the USAP and Raytheon Polar Services–the NSF’s prime contractor–rely on older geosynchronous satellites with large inclinations (12.5 degrees to 13 degrees). For instance, the South Pole station can only count on 11.5 hours of connectivity daily, using the 20 year-old Marisat F2 satellite, aging GOES 3 and TDRSS F1. This also explains why all Antarctic antennas are pointed horizontally, to catch any available satellites as they clear the horizon.

Still, it’s the cold that concerns people like Nick Powell, the Raytheon project manager responsible for the South Pole earth station. "Extreme cold affects metal components, causing fatigue and breakage," Powell said in a recent e-mail interview. "Though this is rare, it is still a risk. Cable damage is the most common manifestation of this phenomenon, particularly if they must flex with antenna movement. Typically we use cables which remain ‘flexible’ at extreme cold temperatures across azimuth and elevation rotation axes where breakage probability is high. These jumpers are designed for quick replacement should they break.

"Drive system performance constitutes the other major concern," Powell continued. "If a seal breaks on the gear reducer, we’ll lose lubricant with resulting loss of antenna movement."

Not surprisingly, the gear lubricants used in Antarctica are rated to work at -60 degrees F. Nevertheless, the USAP heats its components wherever possible. "Our electronics equipment, with the exception of the devices in the antenna feed, are kept near room temperature," said Powell. "Heaters even keep feed electronics reasonably warm (40 degrees F) inside an insulated enclosure at the antenna focal point. Heaters and insulated enclosures keep azimuth and elevation drive systems ‘warm’ (temperatures range from -10 degrees to +30 degrees F). The antenna and interconnect cables are the only things kept at ambient temperature."

Even with the best protection, problems do occur. This is where constant monitoring makes the difference in Antarctica. For example, the elevation motor current draw increased in August. The reason? "Examination of the antenna showed snow packed into the support frame," Powell said. "The added snow weight pushed the center of gravity forward and unbalanced the antenna. Accumulating snow increased the motor’s work with a corresponding electrical current increase."

As well, the South Pole ground station installation is not perfect. For instance, "a design flaw prevents integration between the heater controls and the overall monitoring and control system," Powell wrote. "This prevents direct, remote monitoring of device temperatures and heater setpoint adjustments.

"We installed a Webcam to remotely monitor temperatures, but have no control," he added. "Changing the setpoint requires a walk to the site, not fun in the middle of winter."

This said, Raytheon is one of the first companies to establish a major antenna system in an extreme environment like the South Pole. "We’re breaking some really new ground here," Powell concluded. He’s right: thanks to its earth stations, the USAP is able to link its three Antarctic outposts directly into the Foundation’s WAN, not just for voice calls, but also for high-speed data and even video connections between the South Pole and the United States.

Other Cold Spots

Of course, Antarctica is not the only place where satellite earth stations face extreme cold. For instance, in the Norwegian city of Eik, Telenor Satellite Services operates a large teleport in support of North Sea oil platforms. At 58 degrees N latitude on Norway’s southwest Atlantic coast, Eik is just below the Arctic Circle. As a result, snow and cold is an everyday fact of life, says Tom Surface, Telenor’s manager of media and public relations. "Also challenging is the long Arctic night, which keeps us in darkness for months at a time," he notes. "Still, given that our Eik teleport is able to see three oceans, plus access the major polar satellite, this is a location that’s well worth the trouble."

Meanwhile, in Canada’s north, Telesat has earth stations based throughout the Arctic Circle. It has a major hub in Iqualiut, the capital of the Nunavut territory at 63 degrees N latitude. "We have a number of antennas that support both federal and territorial clients," explains Paul Bush, Telesat’s vice president of corporate development. "We cover everyone from Environment Canada–they provide weather information–to the Royal Canadian Mounted Police." Also supported are radio and TV broadcasters, telephone companies, banks and a whole range of commercial data clients, including Chrysler and General Motors. In a unique twist, Telesat also supports air traffic control throughout Canada’s north. "When a pilot is landing their plane in Nunavut, their approach is actually handled by air traffic controllers in Montreal," Bush says. "In fact, all air traffic control in the North is handled by southern controllers, thanks to satellite links which send data back and forth over thousands of miles."

As with the South Pole, it gets very, very cold in Canada’s North. Still, one hazard that South Polers never face is polar bears. As the photo above shows, polar bears have been known to hang around the earth stations, looking for food. Although their preferred source is seal, hungry bears can be a threat to humans.

From Cold To Hot…Very Hot

When it comes to cold, people like IDB Systems’ Technician Robert Dixon know all about it. After all, IDB Systems installed the 4.9-meter antenna and radome at the NSF’s Palmer Station site in Antarctica. "We had to wear two sets of gloves with oxygen-activated handwarmers in them in order to work outside," Dixon says. "The trouble is, many of the radome bolts were so small, that you had to take the gloves off in order to work with them. This meant that we had to take turns with one person freezing their fingers for a few minutes, then turning over the task to someone else." Still, Dixon probably prefers freezing to the heat in Kandahar, Afghanistan, at least the weather he experienced during a recent installation there. Actually, it was not the 130 degrees F in the sun that bothered him so much, as it was the gawkers who gathered around his work site.

The time was just after the U.S. attack on Afghanistan, which unseated the Taliban and put Al Qaeda on the run. IDB Systems had been hired to install a new 4.6-meter earth station in Kandahar to replace one destroyed during the invasion.

Dixon was hired, along with a local crew, to install the new earth station. "We were located about 40 minutes’ drive from the Kandahar airport, where the U.S. forces were based," he says. "I was outside working on the antenna with my crew, when some people walked up. As it turned out, they were members of the Taliban and Al Qaeda, coming to see what the American was up to. Evidently the recent U.S. military success hadn’t driven them so far away after all."

Unable to speak the local language, Dixon could only wait and watch as his translator sat down with the Taliban and Al Qaeda to discuss his fate. "When I saw the black turbans, I decided the smartest thing to do was to keep my head down and keep working," Dixon says. "For the next three hours, my translator sat down with them and talked. Fortunately, he must have said the right things, because the Taliban and Al Qaeda members eventually got up and left." So what did Dixon’s translator discuss with his visitors? "They were evidently trying to decide whether to kill me, or to let me continue doing what I was doing. As it turned out, the Taliban and Al Qaeda evidently liked the idea of me restoring satellite communications to the area, because they opted to let me live. In fact, as my translator described it, they were actually quite excited about having communications restored, and thought what I was doing was a good thing."

Not All Remote Challenges Are On Land

So far we’ve looked at regional outposts operating in bitter cold and dangerous heat. However, the same problems also exist for water-based earth stations.

Take Sea Launch: the ship-based launcher system operated by Boeing. In order to do its job, Sea Launch has to send both its launch platform–a converted oil rig–and command ship into equatorial waters days before liftoff. Once on station, both ships have to be self-sufficient until the launch is done: completely self-sufficient.

"We must have enough supplies on hand to last 45 days at sea," says Sea Launch Mission Director Daniel Dubbs. "To accomplish this, we provision everything from fresh fruit and vegetables to computer paper, medical supplies and electronic spares. And we need lots of whatever we require, because we typically take 310 people with us for each launch mission."

Of course, when it comes to unforeseen problems, launch vehicles are like poster children for Murphy’s Law: whatever can go wrong, will. This is why Sea Launch does not mess around when it comes to packing spares. Rather than try and guess what might fail at sea, "we keep a complete, fully-operational ‘donor rocket’ onboard the command ship," Dubbs adds. "This way, there’s nothing we can’t replace on-site."

In order to maintain reliable communications–a vital part of any launch system–Sea Launch has installed gyro-stabilized satellite antennas on both ships. "We have our own private communications network, with the hub being based in Brewster, WA, and another site in Moscow," says Dubbs. "During launch operations, we link both ships electronically using marine radio. As a result, this allows us to use the command ship’s satellite system as a primary, and the launch platform’s satellite system as a back-up."

Beyond providing constant communications, satellites are central to accurate launches. The reason: in order to place payloads into orbit correctly, the Sea Launch crew needs to be in the right place each and every time. Unfortunately, one patch of ocean pretty much looks like every other patch. That is why Sea Launch relies on GPS-based locating systems to ensure that the launch platform is where it should be.

"Our motto is ‘have launch pad, will travel’," Dubbs quips. "Thanks to effective satellite communications and positioning, we can do exactly that for our clients."

Points In Common

Despite the differences between the ground stations described above, all have qualities in common. First, there is the environment: whether cold or hot, wet or dry, these regional outposts function in conditions that are hard on man and machine alike.

Second is supply: in most cases, it is extremely difficult to get people and parts to these locations on a moment’s notice. In Antarctica, for instance, researchers have to wait for the weekly ship to bring in supplies from South America. Meanwhile, in Afghanistan, everything has to be cleared through military authorities who already have their hands full with other equally-pressing matters.

Third is the unexpected: there is nothing like the combination of extreme conditions and poor supply routes to inspire equipment to act strangely. Add in occasional visits from polar bears and the Taliban, and it is clear that regional outpost work is not for the faint-of-heart.

This said, dedicated satellite professionals keep rising to the challenge: installing and maintaining ground stations in the toughest places on Earth. As a result, it is possible for Nick Powell to e-mail Via Satellite from the South Pole–no matter how bad the weather is–and for Afghanistan to reconnect its voice and data lines to the world.

James Careless is the senior contributing editor to Via Satellite.