Each day, hundreds of NGOs and UN agencies access internet services which come from satellites in space. Generally these services are accessed by using large dishes at sites which are located in very remote locations. These dishes and their associated electronics are known as VSAT. Save the Children is operating 50 sites across Africa. Various UN agencies such as WFP and UNHCR operate hundreds of these system. Satellite based internet is very reliable if the right provider is selected. In this article, we are going to unveil the technology behind the scenes in Germany which make this vital service to remote locations so reliable.
Dishes, small and large
The technology deployed to remote field sites is fairly simple. Typically a system will consist of a dish which is 1.2m to 2.4m depending upon which satellite and frequency is used. Inside, there is a modem connected to the dish outside and it’s the modem which feeds internet access into the local office network. At the teleport things are complex, much more complex. Dishes are much larger as they need to connect to many remote stations via the satellite. There may be many large dishes at the teleport as larger organisations may use multiple satellites to reach wide area via multiple foot prints.
The largest teleport in Germany is at Raisting, close to Munich. This teleport used to be owned by Deutsche Telecom but sold on to EMC, a private operator who provides services to hundreds of UN sites. This site was opened in the 1960’s and its build quality is quite amazing. Further North in Germany is the CETel teleport which is used by Speedcast to provide its service to the 50 sites operated by Save the Children International. The CETel teleport is much newer. Unlike the massive antennas in Raisting, CETel is using smaller lightweight antennas.
Raisting history – Cold war and football
The first aerial was built on the site between 1962 and 1962. It was initially used to provide telephone links between the EU and the USA. The dish is housed inside a dome and is still in working order, sometimes used for educational scientific experiments. The Dome and its equipment is now set up as a museum.
Aerials located at the site were used as part of the secure hotline which linked the Whitehouse in the USA to the Kremlin in Russia (Formerly the USSR). Whilst a red telephone has been used in movies etc., the cold war hotline was never a red telephone. The link was initially a telex line. Later it was changed to Fax. These days, the link exists as secure email between the two presidents.
In addition to voice communications this site has seen some historical broadcasts such as the Olympic games. More recently the FIFA world cup was broadcast to the world during 2006 from Raisting.
How it all works
The teleport is a 24×7 operation which is providing essential communications links to VSAT sites across a huge area from the Atlantic Ocean to the Indian ocean. The clients range from the UN and NGO sites in remote locations to expensive superyachts and cruise liners at sea. This is serious business and a short break in service would cause a lot of inconvenience to many. In the case of some commercial operations such as oil exploration, the loss of internet access could lead to significant financial losses. On this basis, many teleports such as the ones operated by CETel and EMC have ensured that all possible points of failure have been covered.
Electricity is provided to the 20,000V site ring main by the local power company at Raisting. As a backup, there are a number of generators around the site which has the capability to deliver over 4,000 KW of power. This is enough energy to power a small town. Enough fuel is stored at the site to run the generators for a few weeks.
In the event of a power failure, generators can take a few minutes to start up. To bridge the power gap, a giant UPS system is in place to keep things running. Many of you will be familiar with the APC UPS which is a combined battery and inverter. The pictures below is also a UPS, but at an enormous scale. This UPS system is so massive that it takes up two floors. The inverter units are on the upper floor, and the batteries are in the bunker. The batteries shown below is just one bank of two in one room, there are other rooms with more batteries. The UPS has enough capacity to run the centre for up to 8 hours.
Other engine rooms exists to provide other essential services. In the picture below left, boilers are used to generate hot water which is feed to the antennas. Elements in the back of the dishes are heated by the hot water loops to prevent ice forming on the dishes. The heating is essential as the snow which forms at around 2 degrees (locally called “Sticky Snow”) can change the reflective shape of the dish, thus causing communications issues for the remote VSAT sites. Heating is really expensive so to ensure that not too much energy is used up, a very sophisticated monitoring system is in place to make sure that just enough energy is used to keep the dishes clear of snow and ice (Local monitoring panel shown in bottom right picture).
The power and the heating is just part of a much bigger system which connects the remote VSAT systems to the internet. We are now going to look at some the electronics;
Signals from the dish will be routed via several systems to clean up the signal by reducing background interference. Space is a very noisy place and as the satellites are 36,000KM away, the signals will be weak, so need to be amplified. These signals will eventually arrive at a modulator / demodulator which is a device which turns internet data format into a form which can be transmitted through space.
The picture to the left is the iDirect Hub, which is the technology used by Save the Children and other organizations for their VSAT. Other technologies such as NewTec and Hughes are also popular. These technologies are the demodulators and modulators and as you might expect, these hubs also support other tasks such as network monitoring so that technicians at the centre can check that are performing correctly.
The hubs are kept in a data centre which is separate to the large dishes. It is here where Space meets the Internet. Signals arrive via fibre optic cables from the dishes and then linked to the internet via dark fibre to the internet.
Some clients may host their own equipment within the teleport data centre.
The massive aerials at Raisting are mounted on a multi-level building (Which also contains a toilet!). Fairly high up in the building is another electronics room full of racks which just deal with the radio frequency. The picture on the bottom left shows the units which convert the fibre transmitted information from the data centre. The middle picture is the up-converter which converts the signals into radio frequency, and finally the picture on the right is a power amp which makes the signal powerful enough to send to space.
From Large to Small!
Typically, VSAT stations used in the remote field sites are too large to carry in an emergency and can take time to set up. At the Raisting teleport, there is a team of engineers who design solutions for field use. The VSAT system shown below is designed to be split up into 5 cases. EMC have worked on the transport cases so that each one weighs less that 23KG which is the standard weight for each item of baggage allowed by most airlines.
Portable VSAT is really designed for short term use such as for emergency responses. It’s during a major crisis where responders will need access to the internet so that they can coordinate activities. Initially, even more portable internet solutions such as BGAN will provide instant internet access from a device which is smaller than a laptop, however at $5 per Mb, BGAN is expensive to run, which is why a portable VSAT needs to be flown in shortly after a response has been launched.
Where organizations have long term operations at remote sites, or short term projects following a disaster, it is important that people working in remote and disconnected locations are provided with a reliable connection. VSAT providers such as EMC, Speedcast, Eutelsat, Castell, AST, NSSL and many more all have reliable teleports. They build in plenty of redundancy such as multiple power suppliers, multiple internet links and even a spare standby dish which can be trained on a satellite if the normal dish fails. I have visited three of these teleports over the years, all operated by different organizations. One thing which is common to all of them is the people. They are highly trained, experienced and committed. Above all, they really enjoy doing their job in the data centre. It’s the quality of the people and technology combined which helps us stay connected with very little downtime at all.