What Is GPS?

GPS stands for Global Positioning System. It is a satellite radio navigation system developed by the United States Department of Defense. Research on the system began in the 60s and the first GPS satellite was launched in 1978. It took some time for the whole system to go online, but it was finally fully operational on April 27, 1995. Previously, the GPS network was only for the military. Is used, but in the 1980s the United States government authorized the general public to use it. The GPS network consists of a Satellite Earth Monitoring Station GPS Receiver What is a GPS satellite? There are currently 24 satellites orbiting the earth with 6 different orbits. Each satellite completes two orbits around the Earth each day, traveling at a speed of 7,000 miles per hour. At the highest point of their orbit, they are more than 12,000 miles above the Earth. From this altitude, a large percentage of the Earth's surface can receive satellite signals. The GPS unit works by receiving multiple satellite signals and calculating the receiver's position based on a triangle of different signals. Accuracy increases with each additional satellite signal received, so the orbits of the satellites are set so that at least 4 signals are received at most points on Earth. Of course, this is only in theory because the landscape around you is blocking some or all of the GPS signals. What is a GPS Earth Monitoring Station? There are four unmanned surveillance stations in the US and one manned master station in Colorado. Springs, Colorado. Four unmanned stations transmit location data from satellites to the master station. The master station uses the transmitted information to correct the location of the sat tiles and returns the correct information to the satellites. It synchronizes the data that each satellite transmits to your GPS receiver and ensures that your receiver always works with accurate information. What is a GPS receiver? GPS satellites transmit low-power radio signals that can only be received when there is a "line off-site" for a live satellite on your GPS unit. Signals can make things like glass, plastic, and clouds ********** but not solid structures like buildings or stones. The GPS unit works by triangulating your location based on the positions of at least three satellites in the GPS system. It compares the time it takes to receive a signal from each satellite in the range and calculates your location based on data. If you can only take three satellite signals, your GPS unit can report your location at latitude and longitude. However, when the GPS unit receives signals from at least four satellites it also counts your height. Now it can also report your travel distance, distance to destination, travel speed, and even your altitude if you have an altimeter on your GPS receiver. How accurate a GPS unit is depends on its ability to detect and block the satellite signal. As you might expect, you'll get what you pay for and the more expensive GPS units are usually more accurate. The best consumer units claim accuracy within a few feet, while older or less expensive units maybe 30-40 feet or more. Where you want to use your GPS receiver can determine if it is worth spending the extra money for increased accuracy. If you are using your GPS unit with a good open view over flat terrain, the less expensive unit will work almost as well as the top-of-the-line receiver. However, if you plan to use your receiver in a dense tree cover, you will get better accuracy with a more high-end GPS unit when hiking in valleys or narrow valleys, or between tall buildings. Now you know how GPS works and "What is GPS?" You know the basics. Can answer the question.