MITSUBISHI LANCER RALLIART 2011 8.G MMCS Manual
Manufacturer: MITSUBISHI, Model Year: 2011, Model line: LANCER RALLIART, Model: MITSUBISHI LANCER RALLIART 2011 8.GPages: 177, PDF Size: 15.86 MB
Page 11 of 177

GPS Measurement 1-8
GPS Measurement
GPSGPS is the acronym for Global Positioning System.
The MMCS uses GPS satellites that orbit the Earth
in space at an altitude of approximately 20,000km.
Electromagnetic waves from at least three of these
satellites are received on the Earth by the system,
making it possible to learn the current position.
Map MatchingWhen traveling with just the GPS, there may be errors
in the current position display. In such case, “map
matching” is the function that compensates for this
error by assuming that vehicles travel on roads and
placing the current position on a nearby road.
GPS antenna positionThe position of the vehicle is determined from the
weak electromagnetic waves from GPS satellites
received by the GPS antenna.
mngi263
NOTESince it may not be possible to accurately display the
vehicle position if the electromagnetic waves from
the GPS satellite are blocked, be sure to obey the
following:
carbon to the window glass.
antenna.
GPS antenna.
Situations where accurate measurement is not
possible
In situations such as the following, accurate
measurement may not be possible.
The US Tracking and Control Center controls the
satellites. Sometimes the electromagnetic waves are
stopped during upgrades or repairs to the system.
NOTEsatellites by placing objects on or around the GPS
antenna.
of the GPS antenna, as it could prevent accurate
measurement.
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GPS Measurement 1-9
IntroductionSituations where errors occur in the current
location and direction
GPS satellite unit is poor.
States Department of Defense, so sometimes the
satellite itself intentionally sends incorrect position
data. The measurement error will increase in this
kind of situation.
because the distribution of the GPS satellites is poor
(when the satellites are aligned in approximately the
same direction or height). (The best accuracy for
GPS measurement is when signals are received from
multiple satellites; a satellite directly over the vehicle
and others just over the horizon to the north, south,
east and west.)
GPS measurement, errors are slightly more likely in
the horizontal direction.
vehicle height can be received, but electromagnetic
waves cannot physically be received from satellites
positioned lower than the vehicle height (on the far
side of the Earth). This means that an adequate
height comparison is not possible.
3D MeasurementWhen valid electromagnetic waves can be received
from at least four GPS satellites, the 3D positions of
latitude, longitude and height are calculated.
2D MeasurementWhen valid electromagnetic waves can only be
received from three or less GPS satellites, the height
is assumed to be unchanged from the previous
measurement and the 2D positions of latitude and
longitude are calculated. If this happens, the accuracy
of the position is less than with the 3D measurement.
No MeasurementIf no valid electromagnetic waves can be received from
the GPS satellites, there is no measurement.
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Page 13 of 177

Error in the Current Location 1-10
Error in the Current Location
In situations such as the following, the current
location may not be correctly displayed.
(E.g., when transported on a ferry or trailer)
engine
(E.g., on a turntable in a parking area)
such as mountain roads with steep inclines
in a straight line or gentle curve
(E.g., freeways)
such as in a traf c jam
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