Positioning Technology - Pioneer AVG-VDP1 Operation Manual

Appendix
Additional Information
Speed pulse error. Please power off the
system and check the installation. After
checking, please re-boot the system and press
OK .
Speed pulse error.
After checking the speed pulse cord, touch
OK.
Speed pulse wire is disconnected. Accuracy
cannot be ensured without speed pulse.
Please be sure that the speed pulse wire is cor-
rectly connected to the system.
Speed pulse cord is disconnected.
After checking the speed pulse cord, touch
OK.
Angle of the unit exceeds permitted level.
Please reinstall the unit correctly.
Installation angle of this unit exceeds permitted
level.
After reinstalling this unit correctly, touch OK.
The system has detected a change in the
angle of the unit. Learning status for Gyro
Sensor has been initialized.
The system has detected a change in the angle of
this unit.
Touch OK.

Positioning technology

This unit accurately measures your current lo-
cation by GPS (Global Positioning System).
Positioning by GPS
The Global Positioning System (GPS) uses a
network of satellites orbiting the Earth. Each
of the satellites, which orbit at a height of
68,900,000 feet (21,000 km), continually broad-
casts radio signals giving time and position in-
formation. This ensures that signals from at
least three can be picked up from any open
area on the earths surface.
32
En
The accuracy of the GPS information depends
on how good the reception is. When the sig-
nals are strong and reception is good, GPS
can determine latitude, longitude, and altitude
for accurate positioning in three dimensions.
But if signal quality is poor, only two dimen-
sions, latitude and longitude, can be obtained
and positioning errors are somewhat greater.
Positioning by dead reckoning
The 3D Hybrid Sensor in this unit also calcu-
lates your position. The current location is
measured by detecting driving distance with
the speed pulse, the turning direction with the
Gyrosensor, and inclination of the road with
the G sensor.
The 3D Hybrid Sensor can even calculate
changes of altitude, and corrects for discre-
pancies in the distance travelled caused by
driving along winding roads or up slopes.
Also, this unit learns the driving conditions
and stores information in the memory; thus,
as you drive more, the precision of the posi-
tioning becomes more accurate.
The method of positioning changes as follows
depending on whether the speed pulse of your
vehicle is detected or not:
3D hybrid mode
This is active when the speed pulse is de-
tected. Inclination of the road can be detected.
Simple hybrid mode
When the speed pulse is not detected, posi-
tioning is performed in this mode. Only hori-
zontal movement is detected, so it becomes
less accurate. Also, when the positioning by
GPS is not available, such as when your vehi-
cle enters a long tunnel, the discrepancy be-
tween your actual and calculated position may
become bigger.