GPS and how it works

GPS stands for Global Positioning System, a satellite navigation system with 24 satellites in orbit. These satellites have been used instead of the U.S. Department of Defense for military purposes, and were called NAVSTAR. The first satellite was launched in 1978 and the twenty-fourth and last satellite was finally held in 1994. 1980 Navstar was available to the public for commercial use.

GPS works 24 hours a day in all weather conditions. L 'Satellites orbiting the earth twice a day in a given orbit, about 12,000 miles above us. In orbit, the satellite traveling as fast as 7,000 mph. Since they are in orbit, to transmit information to receivers on Earth. The receivers use this information to calculate your location. This calculation has been a transfer by determining the difference between the time and if the recipient has been done. This is then used to calculate the distance and positionthe receiver.

For a receiver for the position of latitude and longitude to be calculated information received from three satellites. To calculate the length, width and height of a receiver must be able to receive information from four or more satellites. After position is known, the GPS can tell you with information on speed, distance, distance to a desired destination, sunrise and sunset, bearings and other information.

While in orbit, theThe satellites are powered by solar energy. They also have backup batteries that are used in case of non-solar energy as a solar eclipse. The energy for the low power of satellite missile, which consider the correct use in orbit. At any time, only about 50 watts or less is used to transmit information. The satellites have a lifespan of about ten years, and the U.S. Department of Defense is continuing and the launch of replacement satellites. Each satellite is about 2000Pounds and seventeen feet wide, when the solar cells.

GPS receivers are generally accurate within 15 meters. that investing in a receiver there are no other taxes or other equipment necessary to access the GPS signal. very accurate measurements are required to be, Differential Global Positioning System (DGPS) accuracy fifty-seven within four meters. The United States Coast Guard operates the most popular DGPS.

Two of the transmitted signals and powercalled L1 and L2. The L1 frequency is used for civilian purposes. These signals are relatively low power signals travel by line of sight, so that through the clouds, glass, plastic and go, but not solid objects like buildings or mountains. In each transfer, the satellite sends three types of information, its pseudo-code, ephemeris data and almanac data. The pseudo-code is a code that the SI is the information sent via satellite identified. Ephemeridestells the receiver where the satellite should be at any time of day and almanac data sends information about the status of the satellite, the date and time. The almanac data is the part that is essential to determine your location.

Thanks To : Garmin Forerunner 405 Garmin nuvi 1390-1390T Garmin nuvi 265W-265WT