Satellite Navigation



Orientation made easy

Most of us are quite familiar with this situation: "Honey, I think we should have turned right at that crossing." "As if I didn't know where we're going! I'm merely taking a different route than usual." "You can ask the way at that gas station up ahead." "There's really no need, I know exactly where we are!"

Figuring out the right way has bothered people for thousands of years. Whereas orientation on land is still relatively simple, that is certainly not the case for sea and air navigation. Here there are no answers like, "just turn right at the next wave, or cloud...". Instead, one has to depend on optical orientation aids like mountains or stars. But the information they provide us is usually imprecise and often enough disappears in clouds and fog.

These days, modern satellite technology not only helps hikers, bikers, people driving cars, captains of aircraft and ships, as well as astronauts in the space shuttle to find out where they are, but also to find the right course to their target. The next question is, "how precisely can location be determined?" You can find out the answer yourselves after conducting the experiment. Use the chance to bring yourself up to date on the latest developments in orientation, and test how modern satellite navigation technology functions and how good it is.

Increased reliability thanks to a global system

Navigation systems help us to find out the relevant values needed for getting us from a given location to a particular goal (navigation). In addition to the U.S. GPS (Global Positioning System) and the Russian GLONASS (Global'naja Navigatsionnaja Sputnikovaja Sistema) systems, Europe will have its own independent navigation system in place in a few years. Compared with the two existing systems, it will have higher reliability worldwide. And accesibility for private users will also improve, because 30 additional satellites are involved. These satellites will send out signals similar to those of GPS.

The German Aerospace Center (DLR) is contributing to the new navigation system in atmospheric, signalling and multipath propagation research, as well as in antenna and receiver development.

What does Albert Einstein have to do with using satellites to play hare and hounds at DLR_School_Lab Oberpfaffenhofen?

Even if only to find out the answer it would be worth visting us! You'll learn how navigation works with ground systems and, using the example of the U.S. GPS, with satellites. You'll also learn how precisely one can navigate with GPS as a private user, and which errors can arise from the atmosphere and the intermediate environment.

On a satellite-supported high tech version of hare and hounds you can easily find out how to use a GPS receiver. But beware, technology can be tricky! Does it work reliably in a tunnel, or if one of the satellites misfunctions? As to the Einstein connection, we'll only say here that he found out that mass bends light rays and thereby slows them don. You can learn the details and more during your visit to DLR_School_Lab Oberpfaffenhofen!

Further information: Navigation and guidance systems


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Experiment description Satellite Navigation (http://www.dlr.de/schoollab/en/Portaldata/24/Resources/dokumente/op/Satellite_Navigation_korrigiert_04.11.pdf)