Defining location

Location is broadly about knowing where someone or something is. It may be about knowing where you are in order to navigate to somewhere else or find something. Or it may be about knowing where other people are, for all sorts of reasons. At different times differing types of location information are useful. For example, when using a car satnav the precise position of the car in terms of its geographic coordinates is important. In another situation it may be sufficient to know whether a person is at home or not. Sometimes location is relative, such as wanting to know how far away the nearest restaurant is. Sometimes it is helpful to know also in which direction a person is orientated, for example in order to provide them with information on the building which they are viewing. Sometimes precision is important; in other situations location within a kilometre or two may be adequate. Hence, understanding location is not just as simple as assuming that once a GPS fix has been achieved the problem is solved.

This section looks first at the different methods which a device can use to locate itself or be located by networks. Then we discuss some of the location-based applications that might be of interest. Finally, we look at why many of these applications are not widespread and note the implications of this for the wireless industry and other applications.