GPS technology in the construction of the airport

1.2 GPS ground control segment ground control in part by the distribution of a master control station in the world, five monitoring stations and three into the station form. The role of master control station is based on the monitoring station on the calculated GPS satellite observation data and satellite ephemeris error and clock correction parameters of the atmosphere and into the station through the data to the satellite to go into; but also to control the satellite, provide a time basis, issue instructions to the satellite, scheduled backup satellites. The role of monitoring stations to receive satellite signals, monitoring the satellite working. Into the station's role is to be calculated and prepared by the master station satellite ephemeris, clock error, navigation data and other control commands to the appropriate satellite and other data into the storage system, and monitoring into the correctness of the information.

1.3 GPS user equipment by the GPS receiver user equipment, data processing software and the corresponding user terminal equipment such as computers, meteorological instruments, whose role is to accept signals from GPS satellites, the use of navigation signals and so on.

2, GPS positioning principle

GPS system is a distance of intersection method using satellite navigation and positioning system receiver antenna according to the user in the state in which the measurement can be divided into static positioning and dynamic positioning. Figure l shows: the position of P point in the need to set up GPS receiver, at a time ti while receiving the three (A, B, C) above the GPS satellite navigation message sent through a series of data

Processing and computing time can be obtained by the GPS receiver to the GPS satellites from SAP, SBP, SCP, also available through the reception of satellite ephemeris time the location of the satellites in space (three coordinates). The method used to obtain P from the intersection point