A Survey on Global Positioning System Processing Methods

Abstract

The Global Positioning System (GPS) is the newest achievement in this search for precise positioning. Though originally intended for military use, GPS has been found useful in many civilian applications including surveying and navigation exceeding its original purpose. The receiver then calculates the distance to the satellite by measuring the difference between the time when the signal is received and the time when it was sent, and multiply by the speed of light. To calculate its precise latitude, longitude, and altitude, the receiver measures the distance to four separate GPS satellites. Conventional methods of surveying and navigation require tedious field and astronomical observations for deriving positional and directional information. Rapid advancement in higher frequency signal transmission and precise clock signals along with advanced satellite technology have led to the development of Global Positioning System (GPS). The outcome of a typical GPS survey includes geocentric position accurate to 10 m and relative positions between receiver locations to centimeter level or better.