Portable tracker provides the most basic positioning services

There are a variety of uses for GPS technology today, from basic positioning applications which might provide a traveller with their current location, speed, and direction to their destination, to highly complex applications where the user’s position information is feed into a system that provides location-specific features and services tailored for that user. What follows are some examples of how GPS technology is being used to enhance the capabilities of intelligent vehicle platforms. The initial examples illustrate some of the more traditional positioning applications, such as basic location and autonomous navigation systems, which are already seeing widespread use today. This is followed by examples describing how GPS-derived positioning information is being used to provide location-based services in vehicles today, and how the richness and complexity of those services will increase in the near future.

A portable tracker, while not strictly an intelligent vehicle system, provides a good example of an application utilizing the most basic positioning services provided by GPS technology. These units range from less than one hundred dollars to a few thousand dollars, depending upon their features and capabilities. These devices are battery operated, have a small LCD display and basic, menu-driven user interface. Most of the newer models can detect at least 6–8 satellites concurrently, with many now offering the ability to track up to 12 satellites at once. The more complex units also provide a variety of configuration options, such as the choice of localized datums or different information display formats. Because these devices are small enough to be easily carried in a briefcase or purse, users can take them as a positioning aid when travelling, whether on foot, or by private or public transport. The basic functional blocks of a handheld GPS receiver are illustrated in the picture below.

All of these GPS tracking device provide the user with their current location information, usually in the form of a latitude and longitude reading. Most also provide the user with additional positioning information, including the current local time, elevation above sea level, and velocity, provided enough satellites can be detected by the device. Many of today’s handheld devices also provide some tracking services, enabling the user to store the location of points they have previously reached, allowing them easily to return to their starting location. This can be a very useful feature to those travelling in unfamiliar areas, whether in a wilderness area or in an unfamiliar town or city.

Some of today’s newer handheld systems now have larger displays and removable memory devices that enable the unit graphically to plot the user’s current location onto a map of the local area. These electronic tracker may also provide the ability to enter in destination information, so the user can more easily understand where they are in relation to where they want to be. However, most of these devices fall short of being true navigation systems, since they do not provide any assistance to the user in reaching their destination. Instead, they simply give the user a more complete picture of their current location.