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VSATs are alive and well and growing

By Hans van de Groenendaal. features editor, Engineer IT

Optical fibre-centric companies often give the impression that satellite are fading out the picture, but in fact the opposite is true.  Very small aperture terminal (VSAT) services are growing and remain vital in the communication mix.

Satellites still remain popular and critical to connecting large parts of Africa where many areas have no access to terrestrial solutions. “Networks that use VSATs  for voice and data  are the most popular and, more importantly, more reliable form of connectivity on the continent”’ says Grant Marais, regional vice president, Africa, Intelsat.

Since satellites cover the whole of Africa, access to capacity is available anywhere at any time and not just in city centres or along coastlines as is the case with fibre and submarine cables. A number of countries in Africa still depend on satellites for voice and data connectivity to give them access to international links – from even the remotest areas.

“Even if we see the emergence of more terrestrial connectivity, satellites still play a key role in which we like to call hybrid network topologies. This does not mean that you pull out your satellite networks – it will become part of a hybrid solution to ensure quality of service and uptime and availability as the network may require. This is particularly important in the enterprise environment such as banking, retail and corporate communication where the cost of being down outstrips the expense of providing continuity of service with a VSAT network.”

“We see examples of that in everyday life, just hop in your car and drive to the nearest petrol filling station and you most likely find a VSAT dish at the back of the building”, Marais said. ” Even in Sandton which is most probably South Africa’s most fibre connected suburb!  Many ATM today rely on VSATs.”
VSAT terminals being installed in the Philippines.

VSATs have a particularly useful application in emergencies. It is quick and easy to deploy a system to provide connectivity when terrestrial networks are down or destroyed. A good example of VSAT emergency application was   the deployment  of  satellite telecommunications equipment  by the International Telecommunications Union (ITU) for relief activities in areas of the Philippines severely affected by Typhoon Haiyan – one of the most powerful typhoons ever recorded. The ITU deployed a number of Thuraya satellite telephones, Iridium satellite phones, Inmarsat satellite phones, Inmarsat broadband global area network terminals, VSAT terminals and QUALCOMM deployable base stations.

Marais believes that it is important to consider what will deliver the best communication solution. “Take the USA, it is most probably the country with the largest fibre-based network yet the demand for VSAT is still increasing. There are always new developments, new suburbs or industrial parks where initially there is no fibre network. VSAT terminals can bring voice and broadband data within days and when a terrestrial network is finally in place the VSAT network can be deployed to another new development or reconfigured into a hybrid solution to provide backup should the terrestrial network fail.”

One of the issues about satellites often used against it is latency. The distance a satellite signal has to travel is often much longer than on a fibre connection. For data connections latency is in most cases not a problem and can be mitigated by various acceleration technologies.
New generation Intelsat satellite 
offering narrow spot beams.

There are many new developments such as the use of many small spot beams that can carry both up and downlinks and do away with the use of teleports, greatly reducing latency issues.  Intelsat has developed EpicNG which is a high performance, next generation satellite platform that delivers global high-throughput technology without sacrificing user control of service elements and hardware. There are two satellites under construction that will offer KU-band spot beams. Because Epic NG will have narrow spot beams the system can offer higher bandwidth and more powerful signals which mean that smaller ground station equipment can be deployed utilising far less energy than current ground stations.

The higher power also mitigates issues such as rain-fade. With many spot beams close to each other one could compare the Epic next generation platform with a series of cellular base stations which handover to each other as the traffic passes through. This makes it particularly suitable for services on aircrafts and ships, handing over from one spot beam to another without loss of signal or fringe edge degradation.

If you are still wondering on the future of VSAT, think about the coverage of Madiba’s funeral on TV an currently the Oscar Pistorius trial. Both these events and many others would not have been able to be shown on our TV screen if it was not for VSATs.

Link to the Original Article: EE Publishers

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