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Satellite Communications For Hostile Environments
by Dr. Axel Jahn, Managing Director, TriaGnoSys

Communication is central to managing situations in any hostile environment, be such in the military sphere, in response to an emergency, or when dealing with a major disaster. Must-haves for communication solutions in hostile environments are reliability, robustness, security, portability and ease of operation.

Communications for these situations have been based on radio, satellite, and civilian infrastructures where they exist. New satellite communications technology, particularly picocell backhauling, provides exciting new opportunities that either augment or replace traditional solutions.

Improvements in the backhauling of picocells mean that GSM and UMTS (2G and 3G) networks can now be established literally anywhere, and the hardware allows for the fast and efficient establishment of ad hoc sophisticated telecommunications infrastructures. These networks operate in exactly the same way as a standard mobile phone network, with the crucial difference that they are not dependent on any wired connections: the picocell, which acts as the mobile phone mast, communicates with the network operator via satellite.

Satellite communication in itself is not new or particularly innovative and has been expensive when compared to terrestrial wireless, radio or fixed-line technologies. As a result, satellite-based usage has been, by and large, limited to critical communications in remote, inaccessible areas. Frequently, this has been as a result of a disaster or when secure transmission is a high priority. Until now, it certainly has not been seen as a mainstream contender for network access.

It has been possible for some time to establish a GSM network using satellite technology, but it has been relatively crude and the disadvantages have been significant. They have also been expensive to buy and operate, as well as being quite bulky. The solutions available are not suitable for military, or emergency and disaster response uses – they have been used more for static applications, such as providing GSM access in remote ski resorts.

But the future for satellite-based network provision is about to change – all thanks to the picocell. Picocells have traditionally been used to extend coverage to indoor areas where physical restrictions mean poor signal reception, or to add network capacity in areas with very dense phone usage, such as train stations. However, they can now be backhauled via satellite to provide coverage anywhere. The network has a radius if 700 metres and anyone within that area using a GSM or UMTS compatible electronic device can use it in exactly the same way as if they were in the middle of a city.

System efficiency is the key enabler to the technology behind the new GSM, GPRS, EDGE and UMTS networks based on satellite transport. Much of the pioneering development work that has gone into enabling picocell backhauling has been based around optimisation, including compression of payload, IP Header and signalling.

The reason why compression of headers is so important is because they add a total overhead of 40 Bytes to each voice packet, regardless of the size of the packet. This means that a voice packet of 12 Bytes, used by GSM and UMTS picocells, is increased by more than four times by the headers.

Robust Header Compression is used in combination with the technique of bundling several voice packets into a single IP datagram. This means that very significant compression can be achieved, with overheads being reduced to only 5 Bytes.

The real benefit is when the optimization technology is combined with miniaturisation of the hardware, to the extent that it can be carried by one person. It requires a power source, which can either be a battery pack or a generator – the equipment only needs a 100W power supply, so a small petrol generator is all that is needed.

Finally, a GSM or UMTS network established using a backhauled satellite can be managed by a virtual operator anywhere in the world, meaning that there is no need for a communications expert on the ground. The network is not bound to any local operator, so it not subject to any locally imposed restrictions, and it can use any satellite system.

The advances in technology have meant that the establishment of GSM/UMTS networks in hostile environments is now a cost-effective reality.
The focus here is on the use of picocell backhauling to provide GSM and UMTS networks in hostile environments.

The use of a backhauled picocell technology is never going to replace standard radio technology for military use. Radio meets the essential requirements of military communications and does so securely, reliably and cost-effectively. However, the ability to establish ad hoc 2 or 3G networks using satellite backhauling technology anywhere at any time supplements the options currently available.

The three main functions of military communications are:
1. Providing secure and reliable communications
2. Signals intelligence: intercepting and monitoring enemy communications such as mobile phone calls, satellite phone calls and radio transmissions
3. Electronic intelligence: analysing and tracking the location of communications signals

The fact that a communications network can be set up anywhere at any time is a clear benefit of using a backhauled picocell. In particular, the 700m radius of the network makes the use of a picocell suitable for remote headquarters. In-built NATO-approved encryption can be used to ensure privacy and security in all voice and data communications, which extends to guaranteeing privacy over the satellite link. In addition, the picocell can be set to accept connections only from registered devices, therefore rejecting connections from unknown ones. A further advantage is the point-to-point calls within the network, which are not routed via the satellite, are free, making on-site communications simple.

The portability of the equipment also makes it ideal for signals intelligence. It can be used to jam transmissions, as well as monitor GSM and GPRS content as well as to redirect calls and emails. Therefore, it has significant potential for intelligence gathering and the disruption of any enemies’ communications.

Finally, a network based on a single picocell can handle up to 14 simultaneous calls. This means it can be used for both operational and personal communications. While personal communications are good for morale purposes, operational communications must have priority. To that end, the network can be set up to ensure the most important communications always have priority for the use of the network. In addition, the technology is scalable: further picocells can be added, thereby increasing the number of simultaneous calls by 14 for each picocell added.

Emergency response
As is true with military operations, effective and efficient communications are essential when dealing with large-scale emergencies. These emergencies may be man-made or natural, such as terrorist activity, flooding or widespread fires.

Emergency services use dedicated emergency networks where they exist. However, they often rely on public land-based and mobile networks for communications. All terrestrial networks are subject to failure should power supplies malfunction. If that happens, either at headquarters or a forward operating base, communications can be lost. While contingency planning will cover this scenario, a back-up communications system that is totally independent from any other communications source and that can be established quickly ensures communications need never be lost.

Backhauled picocell networks offer two unique benefits as a back-up solution. The first is the equipment required is simple to hold in readiness at any headquarters; it is also sufficiently small enough to be included in the back-up equipment of a forward unit, such as a fire appliance or indeed a reconnaissance or supply aircraft.

The second strength is that it operates independently of the terrestrial networks—a small generator can supply power. That means that communications will always be available, even if all other networks are not working.

Disaster Recovery
When disaster strikes, co-ordinating a response is often hampered by a lack of information and the inability to communicate to emergency services, government and aid organizations. For example, when in 2005 an earthquake hit Kashmir, the international community responded very quickly. However, much of the effort was misdirected, as there was little information about what was needed, or where it was needed. It was also difficult to communicate what little information was available to the relevant people. That meant some villages were visited by emergency services several times a day, while others received no help at all.

Natural disasters frequently occur in areas that have little or no existing communications infrastructures. Where those infrastructures do exist, there is a strong possibility they will have been knocked-out by the disaster. The ability to set-up and operate a GSM or UMTS network can have a huge impact on the efficacy of the response, both in the first hours of the disaster, and also as the scale of the response grows.

The fact that the relevant equipment can be carried to the right place by one person means that the use of a backhauled picocell network is the ideal solution in the early stages of a disaster, both to report on the situation and to co-ordinate the initial response. In the first few hours of a disaster response, the opportunity to set up a robust communications network is critical to direct aid to the most badly effected areas and thereby save more lives. The network can also play a significant role in the later stages, for example, in a field hospital or a charity’s headquarters.

Hostile environments require a communications technology that is wholly reliable, portable and independent from any other form of communications. Picocell backhauling technology is unique in being able to offer a complete solution.

Dr. Axel Jahn is Managing Director of TriaGnoSys, a leading provider of mobility satellite communications solutions for remote mobile air, sea and land communications from anywhere to anywhere via satellite. Before founding TriaGnoSys, Axel worked at DLR, the German Space Agency. He has been at the forefront of the development of picocell-based satellite backhauling. TriaGnoSys solutions are used for a range of commercial applications, including the provision of GSM/GPRS services on commercial aircraft, cruise ships, container tracking and for military and emergency use.

TriaGnoSys is also involved in a wide range of research projects, focusing on a broad range of mobile satellite communication areas in conjunction with leading academic, government and industry researchers to advance the state of the art in such areas as mobile end-to-end solutions, next generation satcom and aircom, and combined navigation/communications applications and technologies.
Visit http://triagnosys.com/ for more information