BIG LEO SYSTEMS: THE MSS HEAVYWEIGHTS

This is the third in a series of five features on the new Global Mobile Communications by Satellite (GMPCS). It has been prepared to coincide with the International Telecommunication Union's forthcoming World Telecommunication Policy Forum, to be held in Geneva on October 21–23.

The article gives some background on the proposed new Big LEO systems, which promise users seamless voice and even multimedia communications anywhere, anytime.

GMPCS – Global Mobile Personal Communications by Satellite – may sound like a term well-rooted in the realm of the telecoms techie, but it is actually of most interest to those of us who simply need to communicate with others without necessarily knowing where they are – in short, those of us who use mobile phones.

Why? Because GMPCS is the techie way of referring to a range of planned telecommunication services – including real-time voice – which will soon be available globally for the first time. These new services will be provided by a range of new, ultra-sophisticated satellites, which will spin around the earth picking up and distributing calls from one side of the globe to another.

They will provide the ultimate in mobile telephony – a small, handheld unit that will let you connect with people anywhere on the face of the Earth, at any time. In addition, your phone may also support paging, data transfer, and fax. The cost of the call, and sometimes the handset itself, will initially be steep. But historically, the conventional mobile telephony market has shown that an increased volume of traffic, generated by ever more users, led quickly to dramatic reductions in the cost of both equipment and airtime. There is every reason to expect that the same trend would apply to mobile satellite telephony.

So where are these new services coming from, and when? If all goes according to schedule, GMPCS services will be offered initially, at least, by four main competitors – Globalstar, ICO, Iridium, and Odyssey. These Big Four are currently in the process of designing or fine-tuning their systems, and lobbying to attract the interest of investors, partners and customers. As examples, Iridium recently scored a major financial success by securing a new line of credit to the tune of US$750 million from a group of 62 banks, while ICO late last year announced that Hughes Space and Communications International would invest $94 million into the ICO system. The other players will be hoping for similar deals which will facilitate the rapid deployment of their systems.

None of these operators will employ the conventional telecommunications satellites which have been in use for some 30 years, but will build new systems from scratch using a different type of technology. The telecommunications satellites we use today are largish units which occupy what are known as 'geostationary' orbits above the Earth's surface. This means that they travel at the same speed as the Earth's rotation, so, to an observer on Earth, they do not appear to move at all. Such satellites are able to serve large regions, because, at 36,000 km from the surface of the Earth, they are able to 'see' a great deal of the planet at once. The scope of a satellite's communications beam is known as its 'footprint', and generally covers many different countries.

However, no geostationary satellite can 'see' the whole world at the same time. In order to move communications signals around the world, the geostationary satellite must communicate with another satellite directly via an inter-satellite link or via an Earth station.

The delay caused by such complex routing of signals is one of the reasons for the birth of a new breed of satellite systems. When handling voice traffic, a geostationary satellite system must employ a range of sophisticated techniques like echo cancellation to offset the effects of the time delay on the conversation of the two parties making the call. A far more serious limitation of these systems, though, is the need for very powerful transmitters and receivers, necessitated by the distance from the satellite to the user. At present, this power limitation means that no geostationary system can provide personal communications via the kinds of small, portable handsets we can use with cellular systems. A further problem with the current crop of satellites is that they are not always able to offer reliable service at high latitudes. As they orbit around the equator, the angle of the beam at the extreme north and south of the planet means it can be easily affected by topographical features, or even tall buildings.

These factors together mean that traditional telecommunications satellites are not suitable for offering global mobile personal telephony. But work is underway in the field of geostationary satellites to obviate the technical problems which stand in the way of smaller handset size. Engineers are redesigning the systems to deploy very large and complex antenna structures which would increase the power availability from the satellite and reduce the power requirements at the user handsets. As well, advances in satellite technology have resulted in new types of systems, known as Big LEOs, Little LEOs and MEOs, which stand respectively for Big Low Earth Orbit, Little Low Earth Orbit, and Medium Earth Orbit. These systems are non-geostationary – to a user on the ground, the satellites would appear to move across the sky. The new GMPCS proposals plan to use these new satellites to provide mobile telephony, data transfer, facsimile, and even broadband multimedia services to users.

The advantage of the LEO and MEO systems is that their proximity to the Earth's surface (700-1,500 km for LEOs, 10,000 km for MEOs) obviates the need to use high powered transmitters and receivers to send signals back and forth between the system and its users. Instead, the systems can work using small handheld units, around the same size as the analogue mobile phone units of the mid-80s, but with a slightly larger aerial.

Some of the Little LEO systems are already partially operational, and can offer data transfer services and messaging, such as e-mail and paging, at a modest price to consumers and business. It is the Big LEO and MEO systems – the Lion Kings of the GMPCS arena – however, that represent the truly exciting side of new satellite technology, since it is these systems that promise to deliver real-time voice telephony on a global basis. In order to offer global coverage, the Big LEO and MEO systems will operate as a 'constellation', that is, a network of satellites moving simultaneously around the Earth, picking up and distributing telephone calls between users, ground stations and even other satellites.

The technology required to operate such complicated systems is still under development. Nevertheless, Globalstar, ICO, Iridium and Odyssey have already staked out a piece of the market and are aggressively promoting their systems and forging strategic partnerships. With the exception of ICO, all are US-based, and all propose a system of Big LEO satellites. ICO, the UK-based spin-off of Inmarsat, is alone in proposing a MEO-based system.

** While the information has been provided for interest's sake, most pricing comparisons in fact are not meaningful, since the charge quoted by operators is frequently the 'wholesale' price to another operator, and may not reflect the price a user will eventually be charged.

How realistic are these global communications constellations? The answer seems to depend largely on who you ask. Of course, all the proponents are confident of their ability to design, build and operate a state-of-the-art GMPCS service. In fact, many of the systems have been in the planning stages for several years, and a great deal of progress has been made on the various technical complications of managing communications between two moving objects – the user on the ground, who will want the kind of full mobility enjoyed with a normal cellular telephone, and the satellites above, which will have to perform the already complex task of cell-to-cell handover whilst being in motion themselves. Certainly, there remain some unresolved technical problems, but engineers are confident that these will be quickly solved once the satellites are in flight and trials can be run. Given the ingenuity of today's hardware and software engineers, it would seem a fairly safe bet that most difficulties will be able to be ironed out before the systems come fully on-line. It would be unrealistic for early users of these new systems not to expect a few glitches as the final bugs are flushed out, but all in all, complex as they are, there is every reason to believe new Mobile Satellite Systems (MSS) services are certainly technically feasible.

The biggest hurdle for the GMPCS operators may in fact lie elsewhere – in the realm of international regulation and licensing agreements. The legal complexity of negotiating individual licences with each country of operation cannot be underestimated, which is why partnerships with local operators are so important to the Big Four. The issues of spectrum allocation, mobile handset operation, and most importantly interconnection to the Public Switched Telephone Network or other cellular networks with local and interexchange carriers, will not be easy to resolve to the satisfaction of all parties. What's more, there remains the touchy question of settlement agreements – the money exchanged between carriers over the international telephone network for handling one-another's calls. There is a clearly understood mechanism for today's telecommunications networks, but will these same rules apply to the new global systems? The range of questions to be resolved seems at times almost insurmountable. Last year, speaking at the ITU's TELECOM 95 Forum, Iridium furnished a daunting example: if transborder international licences for handsets alone were required between the ITU's Member countries, more than 16,000 agreements would be necessary.

It is for this reason that governments and the industry, as members of the ITU, have chosen to meet for the first time for a World Telecommunication Policy Forum. Clearly, if global solutions can be reached for many of these issues, the chances of bringing the planned systems to fruition will be that much greater. The Forum, to be held at the ITU's home in Geneva, will comprise representatives from telecommunications administrations, local and international regulators, the legal profession, and perhaps most importantly, the telecommunications industry itself – the carriers, equipment manufacturers, and GMPCS operators.

Conference delegates will come to Geneva in the hope of arriving at a comprehensive consensus about how the political, socio-economic and regulatory aspects of these systems should be handled. Agreement in principle will also be sought on issues of equipment standardization and operation. Another area certain to be of concern to many delegates will be the role of these new systems in less developed regions of the world.

Most of the operators have in fact stressed the potential benefits of their systems to countries with deficient telecommunications infrastructure, claiming that, like cellular telephones, GMPCS will allow those nations to 'catch up' with the developed world without the costly (often prohibitive) process of expanding their fixed line network. Whilst true in theory, some have argued that operators are pushing this line simply to cement worldwide agreements, and that in reality the cost of a call over a GMPCS network will be too expensive for most people in the industrialized world, let alone those living in developing countries. Whether the operators will focus on this market, and whether it can really represent a significant source of revenue to them, remains to be seen.

So will sparks fly at the WTPF? Probably not. Most of the sparring has already taken place in the marketplace, and has largely consisted of in-fighting between rival operators in the Big and Little LEO markets. There have been some causalities, and most operators now seem keen to work together, rather than against one another, in order to get a framework in place under which their systems can all operate. This far down the track, most have too much at stake to risk wasting resources on battles with competitors.

What's certain is that, if the industry can create the right conditions, these systems – and their operators – will sink or swim on their own merits. It may be too early to predict the results, but the importance of the game will keep all eyes looking heavenwards.

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