Introduction - Understanding GPS: Principles and Applications - page 11

Figure 1.7 EGNOS geostationary satellite coverage.

vehicles. Market forecasts estimate Global Navigation Satellite System (GNSS)
2018 product sales and services to be $290 billion. (GNSS is defined as the world-
wide set of satellite navigation systems.) By 2020, the GNSS market is expected to
approach $310 billion with at least 3 billion chipsets in use [16, 17].
To illustrate the diverse use of satellite navigation technology, several examples
of applications are presented next. Further discussion on applications and market
projections is contained in Chapter 12.

1.9.1 Land
The majority of GNSS users are land-based. Applications range from leisure hiking
to fleet vehicle management. The decreasing price of GNSS receiver components,
coupled with the proliferation of telecommunications services, has led to the emer-
gence of a variety of location-based services (LBS). LBS enables the push and pull of
data from the user to a service provider. For example, a query can be made to find
restaurants or lodging in a particular area, such as with General Motors' OnStar ser-
vice. This request is sent over a datalink, along with the user's position, to the service
provider. The provider searches a database for the information relevant to the user's
position and returns it via the datalink. Another example is the ability of the user to
request emergency assistance via forwarding his or her location to an emergency
response dispatcher. Within the United States, this service has been mandated by the
Federal Communications Commission and is called Emergency-911 (E-911). (Chap-
ter 9 contains in-depth technical information regarding automotive applications as
well as E-911 assisted GPS.)
An expanding worldwide market is the deployment of automatic vehicle loca-
tion systems (AVLS) for fleet and emergency vehicle management. Fleet operators