Environmental Engineering Reference
In-Depth Information
Chapter 14
Navigation
The word ''navigation'' historically means the art of the steering a ship. Therefore,
changes in operation are related to the route and the journey. Today, navigation is
a widely used method for the optimal regulation of traffic on roads, water, and in
the air. There are two preconditions for modern navigation [
1
]:
• Precise determination of the vehicles', airplanes', and ships' position; and
• Knowledge
of
the
best
routes
to
the
planned
destination
under
current
conditions.
Navigation consists of different elements in road traffic, in aviation, and in
shipping, but the basics are similar in all types of transportation.
14.1 Road Transportation
On the road, vehicle navigation uses an integrated telecommunication system
based on computers, also known as Information and Communication Technology
or Telemetric Technology [
2
]. This system sends, receives, and stores information
via wireless telecommunication devices. The position of vehicles, similar to other
types of transportation means such as airplanes and ships, is determined by Global
Positioning System (GPS) [
3
]. The main elements of the GPS system are satellites
in space with antennae. All means of transportation have a micro antenna, to send
and receive signals to and from satellites.
Corresponding measuring devices are built into waterproof boxes and installed
at ground level in several positions, e.g.,
• As optical sensors over roads, pavements or crossings at traffic lights, hanging
lamps, or on traffic signal posts;
• As induction wire coils in the asphalt on roads; and
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