How Does The Navigation System Work - VDO MS 4400 Manual

How does the navigation system work?

Important notes on the function of your navigation radio
In principle, the system is functional with poor GPS reception, although the accuracy of
the positioning may be impaired by poor or interrupted GPS reception or errors can
occur in the determination of the position, which result in incorrect position reporting.
Start-up characteristics
During the start-up sequence, it is possible that the navigation system will report:
"You are leaving the digitised area". The navigation system assumes that the vehicle is
not located on a digitised road. If other roads exist in this area, the navigation system
may issue incorrect messages. The navigation system assumes that the vehicle is lo-
cated on another road.
Comments
After transport of the vehicle by train or ferry, the navigation system may require a
few minutes for exact positioning.
After disconnecting the vehicle battery, up to 15 minutes may be required for exact
positioning. For this, the vehicle must be outdoors and the system must be switched on
in order to receive transmissions from the GPS satellites.
General information
If the vehicle is parked for longer periods of time,
the satellites continue their orbit. After the igni-
tion is switched on, it may take several minutes
until the navigation system receives signals from
sufficient satellites for evaluation.
The position and movements of the vehicle
are recorded by the navigation system's
sensors. The distance travelled is deter-
mined by the vehicle speedometer signal,
rotary motion in bends is detected by a
gyro sensor (inertial compass). The position
is determined via the GPS (Global Posi-
tioning System) satellites.
The position can be calculated within a
range of approx. 10 m by comparing the
sensor signals with the digital map on the
navigation CD.
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