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GPS versus Galileo.

The Concept.

GPS (Global Positioning System) was originally developed by the US Department of Defense as a satellite supported navigation system. GPS consists of a network of GPS satellites that are positioned around the globe. GPS receivers receive and analyze signals transmitted from satellites. The GPS receiver can calculate its position by triangulating the data it receives from more than three satellites.

The receiver, however, only plays a passive role in locating and visualizing vehicle locations. To ensure that the dispatcher "knows" where a specific vehicle is located, the position calculation of the GPS receiver in the vehicle must be transmitted to the main office by suitable technical means. A mobile communication system is required to transmit the GPS coordinates to the main office. In simplified terms, one could say that an intelligent, active locating system contacts the GPS receiver via radio waves.

The Target Group.

Originally, GPS was exclusively used for military purposes. However, GPS is increasingly being utilized for civil applications in the civilian world - around the globe. The most well known application example of the GPS system is vehicle navigation. With the help of an external or integrated GPS receiver today’s navigation systems "know” the exact location of a vehicle equipped with a GPS receiver. The tolerance is just a few meters. This significantly simplifies route calculation and route changes.

The difference between GPS and Galileo.

Galileo is a new European satellite navigation system, which was developed for civilian use. The system is scheduled for completion late 2010. The system is comprised of thirty satellites that circumnavigate the earth at an altitude of approximately 23,260 km, as well as a network of base stations that guide and control the satellites. In 2004, the serving US Secretary of State and the chairman of the EU Secretaries of State agreed that the Galileo system would be GPS compatible. Both navigation systems can be used in parallel.

The Benefits.

Determining positions can be employed in a vast array of applications, the most obvious of which is navigation: The navigation system can only determine if a driver is on the suggested route, if the navigation system can precisely determine where the vehicle is located. Should the vehicle deviate from the suggested route the navigation system automatically suggests an alternative route. Time till arrival/length of trip and remaining miles are recalculated - this is especially useful to mobile employees. The information the navigation system provides is also of particular interest to the customer: Arrival times can be better forecasted in advance. More specifically customers can receive advance information on shipment arrival times.

Similarly, companies are able to identify the position of company vehicles equipped with GPS receivers. The dispatcher always “knows” where company vehicles are located (for example: also with the help of an interactive map). This simplifies the process of dispatching orders to vehicles. The dispatcher in the main office always “knows” where the nearest vehicle is located. The dispatcher is also able to estimate when the vehicle will arrive at the customer site.

The Opportunities.

Accuracy versus Costs.

One of the most frequently asked GPS questions is: How accurate is GPS positioning? Up to May 2000 the positioning accuracy of GPS was within approximately 100 meters. The high degree of inaccuracy is ascribed to the military origin of the navigation system. Due to the priority military use of GPS, the US military reduced the GPS signal range of accuracy for civilian use.

On May 2, 2000, the White House issued an order to discontinue the GPS selective availability signal degradation. Since then GPS positioning accuracy for civilian applications has increased significantly. Depending on the technology and the price of the GPS receiver, the system is generally accurate within just a few meters. With special add-on technologies and expensive receivers, the system accuracy range is up to just a few centimeters.

The cost benefit ratio is determinative in any decisions regarding the use of these highly accurate GPS receivers. As such, the cost and the added value the more accurate systems offer would not justify their use in tracking vehicles. The cost benefit ratio of accuracy to the next centimeter would be disproportionate for such application scenarios.