Global Positioning Systems and their use

            Global Positioning Systems or GPS are becoming used by a lot of car users in the modern world. GPS is a navigational system that leads you to your destination without taking unnecessary routes to get there. It is a constellation of twenty-four satellites. These satellites radio signals to electronic GPS receivers. Its official name is Navstar GPS.

            The basic idea to build up a navigation system using satellites existed before the beginning of World War two. German aerospace scientist Karl Hans Janke announced a patent for a positioning system concerning aircraft. The design of GPS is based partly on similar ground-based radio navigation systems Additional inspiration for the GPS came when the Russians launched Sputnik in the year of 1957.

            So now knowing the history of the Global positioning system you are probably wondering how it works.  A receiver calculates its position by timing the signals sent by the large amount of GPS satellites high above earth. Each satellite automatically transmits messages containing the time it was sent. The signals travel at the speed of light throughout outer space. The receiver uses the arrival time of each message to measure the distance to each satellite, from which it determines the position of the receiver using geometry and trigonometry. The resulting coordinates are converted to more user-friendly forms such as latitude and longitude, or location on a map, and then is displayed as what you see with your GPS. Since space has only three dimensions you would think that a GPS would only require three satellites, but a three satellite solution requires the time be known to a nanosecond or so, far better than any non-laboratory clock can provide. However, using four or more satellites allows the receiver to solve for time as well as geographical position, eliminating the need for a super accurate clock. While four satellites are required for normal operation, fewer may be needed in some special cases.

            Nowadays private and public vehicles often have GPS vehicle tracking system to ensure their safety when traveling. There are various reasons why car owners and public vehicle operators prefer to have a GPS. Perhaps the main reason for installing the GPS is because of the possible benefits that you can get despite the cost. However, you can find good quality GPS systems online at specific websites that specialize in selling GPS for a lower price. One of the best benefits is that you can determine your location which is a huge plus when looking for that new mall or movie theatre that you have no clue on how to get there. GPS systems are great for a person new to an area or just anyone that loves to travel a lot.