This paper describes three different antenna systems for mobile vehicle applications. The antennas are either patches or derivatives in all cases. The first is a dual-band telephone antenna with a low profile and wide bandwidth. Operating at 900 MHz and 1800 MHz, with a VSWR of better than 1·7, it is a hybrid construction combining a monopole with a top-loading patch shorted to the ground-plane. Extra-shorted pins provide the upper frequency band coverage. It provides monopole radiation characteristics and can be hidden under a plastic panel or mounted on the vehicle roof. The second is a microstrip patch antenna integrated into a laminated glass windscreen for a vehicle. It is fed using a coplanar waveguide feed printed on the innermost layer of the glass, avoiding the need for a contacting feed within the laminate. The patch and ground plane are meshed for manufacturing in the glass to avoid distorting the heat profile when the glass is shaped and laminated. The patch is easily fed from inside the vehicle and is potentially a very low cost design. The final antenna discussed is a dual-band patch antenna specifically designed for the Globalstar satellite telephone system at 1·6 GHz and 2·45 GHz. It also covers the Iridium band at 1·6 GHz. A single circularly polarised patch is used. Dual-band operation results from truncating the corners of the square patch and judiciously placed slots to achieve a band spacing of 1·5.

Current crises in the air traffic industry demonstrate that changes are required to present systems. The levels of delay and poor safety standards being experienced around the world dictate the need for improved Air Navigation Services (ANS). A multitude of reasons explain these problems. For instance, fragmentation of national systems prevents optimum use of the world's airspace. In addition, inherent limitations of present ANS technologies and procedures mean that it is usually not possible to separate numerous aircraft on random routings. Thus, aircraft must often plan their flights along routes and be channelled so that the necessary separation can be maintained. This results in fuel and time penalties, in addition to airspace capacity being consequently constrained. Accordingly, this paper provides an analysis of changes that should occur to ANS during this decade by evaluating current and planned technologies and procedures.

This and the following paper were first presented at NAV 2000 on Thursday, 2 November 2000 – the day devoted to Location and Communication for Land Vehicles.

This paper discusses the need for Intelligent Transport Systems (ITS) and the key factors influencing the Government's Integrated Transport Policy. Typical ITS projects and applications in the UK are reviewed and conclusions drawn.

Sweden and some other countries are currently evaluating and verifying the potential impact of a newly developed, satellite-based GNSS transponder system on future CNS/ATM and ATN systems.

The concept provides the possibility to introduce a distributed, mobile, real-time data processing system, for all properly equipped users in the global civil aviation community being interacting members (air/air, air/ground and ground/ground).

The paper opens with a brief description of the formation and roles of the Civil GPS Service Interface Committee (CGSIC) and its various Sub-Committees, defining clearly the concept of civil GPS status and health information, and the information services which are necessary. The paper then concentrates on international implications, referring to the activities of the CGSIC's international Sub-Committee, the International Information Sub-Committee (IISC). The concepts of national points-of-contact and national information centres are introduced together with a description of their perceived functions, and this is followed by discussion of the products which they are expected to make available. The paper continues to describe the consequences that have been encountered by the IISC, and the action that has been or is being undertaken. The concept of so-called ‘active distribution’ is defined, and is followed by discussion of the dissemination not only of GPS status and health information, but of information about how that information can be obtained. The possibility of legal implications and the consequences is also discussed and developed towards the arguments for appropriate international agreements regarding the civil use of the Global Positioning System.

A research and development programme performed in Sweden over a period of 9 years has created a substantial know-how on the design of satellite navigation user systems. Thus, a basic user system, called the GP & c Total System has been developed and tested over 3 years. This system can serve as a basis for the tailoring of an almost endless number of applications. The system is currently using data from the GPS satellites, but can also be operated with combined GPS/GLONASS receivers. The Swedish GP & c System is an example of how the communication, navigation and surveillance (CNS) concept and the various elements (ADS, ATM, etc.) for a new global Air Navigation System published by the ICAO FANS Committee can be implemented and integrated into a user-friendly operational system. The ICAO 10th Air Navigation Conference (5–20 September 1991) endorsed the FANS concept in which the main elements are based on the implementation of satellite navigation technology.

In a strong wind, groundspeed may vary appreciably during a turn, as, for example, in the case of a landing after a U-turn preceding the localizer intercept. Such conditions are critical for maximum use of the runway, and render human estimation of aircraft motion extremely difficult.

This paper summarizes the tests conducted using a ground-based 4D-guidance program, developed to assist the air traffic controller in maintaining the predicted landing-time sequence with an accuracy better than 10 seconds for each arrival.