Q1.  What benefits will Galileo Phase II bring that EGNOS (European Geostationary Navigation Overlay System) will not?

  EGNOS is not a navigation system. It is a limited-purpose monitoring system designed only to perform checks on the correct performance of GPS independently of the US's own GPS monitoring service. It is incapable of independent fixing and would be useless for navigation on its own. It was considered advisable to build a system to check GPS independently because the United States does not provide any guarantees of GPS performance to civilian users and disclaims responsibility for poor GPS performance over foreign countries. Galileo is intended to be a complete navigation aid capable of independently providing navigational fixes and operating without the aid of GPS.

Q2.  How important is it for the EU to be independent of the US Global Positioning System (GPS) and the Russian Global Navigation Satellite System (GLONASS)?

  Both are military systems without any foreign civil input or control. They respond primarily to military requirements although in the United States' the needs of its own civil community are taken into account albeit without accepting any legal responsibility. Although the United States has a joint military/civil control organisation for GPS, the military side has over-ruling powers. Foreign users have absolutely no say in how either system is operated and both the United States and Russia have consistently refused to discuss any such possibility. In these circumstances foreign users, such as the UK, are unable to certify GPS receivers or other equipment because there is no guarantee of the basic system. For this reason, the use of GPS for tracking vehicles for road-tolling schemes in the UK (for example) will be impossible until the UK can obtain legally enforceable guarantees that the system will always be working to the necessary specification for the purpose. This the United States refuses to provide. This problem is repeated in many other applications and unless the USA changes its stance the only alternative is for the EU to build its own system with a proper civilian control system having legal traceability.

Apart from that, the engineering techniques used in both GPS and Glonass are now almost 30 years old and newer techniques have become available that can be used to design a system superior to either system in such respects as, for instance, interference and jamming. Also, GPS often fails for such purposes as car tracking in urban "canyon" areas because of high-rise buildings blocking the direct path to the satellites. This is a function of the number of satellites in orbit; only a small percentage are at sufficiently high elevations to be seen in "canyons" at any one time. The answer is more satellites in orbit and it has been calculated that to provide reasonable certainty of having enough satellites at high elevations for accurate fixing about 55 satellites are required. GPS has only 30 and there is no proposal to increase this number. Galileo, providing another 30, would remove this problem provided both systems were interoperable.

Q3.  What are the potential benefits of the Public Regulated Service (PRS) system? Is it realistic to expect that Member States will not want to cross-subsidise PRS from commercial services?

  The PRS is designed to supply highly controlled and protected services for those services requiring them. Examples are Government safety services, police, customs and Armed Forces. These users need a fully guaranteed service protected from attack by criminals, terrorists, and interference of all kinds including malicious jamming. If Galileo evidence is to be used in legal matters then there must be hard guarantees that the service can provide the necessary performance at all times. This is an expensive matter, involving back-ups, duplication, constant monitoring and precise record-keeping. The other services provided by Galileo, not being intended for this kind of user, will not be so heavily documented and controlled and their use might then be open to challenge in the courts. A parallel situation exists today where there have been groundings and collisions between ships although GPS has been in use at the time. The fact that the GPS appeared to be indicating correctly and the Master accepted it as accurate is not basically admissible evidence because there is no guarantee, and non is available, that the system itself was performing correctly at the time. It is a lengthy and expensive business proving otherwise using only unofficial records.

  The PRS will be available only to authorised Government-sponsored users who can be trusted with its special encryption codes and receivers. For those users who would not be able to get such authorisation but would want a similar accuracy there will no doubt spring up an after-market of commercial service providers offering improved facilities while using only the Open or Commercial services. A similar thing happened some years ago when for a time the US Government allowed civil users only a degraded signal providing an accuracy of 100m instead of the full 5m. A rash of providers appeared offering enhancement services known as Differential GPS (DGPS) which restored accuracy to 5m for which they charged commercial rates. Should this happen with Galileo it is very doubtful whether such providers would look kindly on also having to subsidise the PRS which many of them would see as a competitor. However, this is very much a matter for political decision and one for the countries concerned to solve at a higher level than the user.

Q4.  Are the arrangements to prevent military use of Galileo sufficiently robust?

  Not being either a politician or a military man this is not a question I am qualified to answer.

Q5.  Are arrangements to oversee the security aspects of Galileo appropriate?

  (Same reply).

Q6.  What are the potential benefits of the programme to UK industry, and to UK users of Galileo, such as NATS?

  In the implementational stages no doubt the benefit to UK industry will be in the ratio to which the UK commits itself to funding, as is the case now. As regards later navigational applications, it will depend on the commercial acumen of British companies and in this respect it is regrettable that there are now no British companies left engaged in fundamental research and development of navigational systems, an area in which the UK once led the world. However, the major applications of Galileo are foreseen to be outside the area of traditional navigation and no doubt once a highly accurate satnav system is in place, with full performance guarantees not presently available for GPS, entrepreneurs will find new market areas. There should of course be considerable benefits to British companies working in the field of satellites in general, and equipment used in launch vehicles. One such company, Surrey Satellite Technology, a spin-off from the University of Surrey, has already obtained a valuable contract for an experimental satellite. An indirect benefit to industry is that the type of engineering needed to design, build, launch and control navigation satellites is very advanced and new to this country and should trigger off increased activity in Universities and research institutes. The Universities of Nottingham and Surrey have been prominent in the past in promoting GPS technology and the introduction of a "home" system, to which they would presumably have much greater access than they have had with GPS, would be a considerable boost to them and the others who would follow. The UK is lagging behind in advanced electronics and some other areas, including very precise timing, and Galileo would provide a new sector badly needed.

  Benefits to NATS would come only in the longer term, when, in agreement with Eurocontrol and ICAO the system might be used for the more accurate control of aircraft movements over the UK. If this came about, and it was proved that it was sufficiently reliable and accurate enough to replace the current short-range navaids such as VOR and DME there could be a considerable monetary saving in the installation, calibration and maintenance of those aids. Further, because it would be available everywhere, at all altitudes, at a predictable high accuracy, it would lend itself to a rationalisation of airways and possibly eventually to their abandonment in favour of area control. This would mean better airspace utilisation and the reduction of air traffic delays.

ABOUT THE AUTHOR

  President of the Royal Institute of Navigation from 1993 to 1996.

  Founder and Chairman of the UK Satellite Navigation Users' Group 1988-1993.

  Founder of the European Group of Institutes of Navigation (EUGIN) 1994.

  Awarded the US Institute of Navigation's Thurlow Award for 1995.

  Awarded the Royal Institute of Navigation's Gold Medal 1995.

  (Both for "The most significant contribution to Navigation of the Year"; the world's first geostationary satellite-based differential GPS system.)

  Author of numerous studies for the EC and others on satellite navigation systems.

  Visiting Lecturer to Nottingham and Surrey Universities MSc navigation courses.

  Expert Witness in the London Marine Courts on the use of satellite navigation.

BOOKS:

  "The Pilots' Guide to Satellite Navigation" Airlife, 1997.

  "Navigation from Balloons to Concorde" Woodfield 2004.

IN PREPARATION:

  "History of the Decca Navigator Company".

Walter F Blanchard, FRIN

19 July 2004