These days our life would be unimaginable without the possibility of accurate position determing. If somebody travels to an unknown place, the question arises always, where I am? The GPS based gadgets help a lot to solve this problem. They can not just determine our postion, they can also show our speed. GPS can not only be used for navigation, we can track routes, and later we can see where we were and how fast we were going. It is a known fact, that the speedometers in cars are not accurate, they show more than our actual speed. Because of this there can be a claim for a portable device,
that can be used for route tracking, and can show the actual speed. In my thesis I specify the building of a portable device similar to this.