Every navigation system has to determine its starting position via locating with GPS (Global Positioning System). This system measures the time it takes for the satellite signals to travel from the satellites to the GPS antenna. To determine the initial position of the vehicle, the system requires signals from at least three satellites. Then the GPS receiver in the navigation unit can compare the data received with the digital map data stored on a CD-ROM and calculate the position with an accuracy of 10 to 15 metres. However, that is still not enough for exact route guidance.
To determine the vehicle position with greater accuracy, the system needs additional sensor data. It generally uses the speedometer signal or a special speed sensor. It can then calculate the route that has been travelled on the basis of the vehicle speed. The system is able to identify even the smallest changes in direction with the integrated gyroscope. The gyroscope functions on the principle of inertia: in sharp curves it deflects more than on the gentle bends of motorway exit ramps. Using this technique of dual locating, based on the starting position, the current vehicle position is constantly revised based on the route travelled and any changes in direction and achieves an accuracy of 3 metres.
The interplay of the different data is crucial for the precision of route guidance. The intelligent software programs from Blaupunkt constantly compare the GPS positions, the route signals and the direction signals with the data on the digital map. This process is known as map matching. After the destination has been entered in the system, the route is calculated from the current position to the destination on the basis of the options the driver has selected. During the trip to the destination, the navigation system constantly uses dual locating and map matching to determine the exact location of the vehicle. If the driver deviates from the recommended route, the system will automatically calculate a new route to the chosen destination.
Turn-by-turn Route Guidance
Accuracy within 10 feet
Split screen capability (Map/Symbology)
User assistant operating introduction, QuickInfo
Save up to 99 positions / destinations into memory
Route options such as fast/short route, avoid motorway/ferry/toll road
POI by Name/Catagory/Distance