GPS locator and navigation system contains three parts, these three parts are: gps satellites and satellite constellation, ground monitoring systems, gps signal receivers.
The gps locator can accurately locate every corner of the earth. The implementation of this technology is still very difficult. Therefore, it is necessary to work through many devices to work together to achieve such a result. What are the usual components of a complete GPS positioning system? Let's let the engineers of SinoTech today explain it to everyone:
The first part: GPS satellites and satellite constellations
It is a GPS satellite constellation consisting of 21 working satellites and 3 on-orbit spare satellites. 24 satellites are evenly distributed in 6 orbital planes. The inclination of the orbit is 55 degrees. For ground-based observers, the same gps satellite will be seen 4 minutes in advance every day. When gps signals are used for navigation and positioning, the stations are to be settled. In three-dimensional coordinates, four GPS satellites must be observed, which is called a positioning constellation. The number of satellites above the horizon varies with time and place, with a minimum of four, and a maximum of 11 visible.
Part II: Ground Monitoring System
The ground monitoring system is mainly used to monitor whether the various equipments on the satellites are working properly and whether the satellites have been operating along the predetermined orbit and keep the satellites at the same time. This requires the ground station to monitor the satellites. At the time, the clock difference is found, and then sent to the satellite by the ground injection station, which then sends the navigation message to the user equipment.
The second part: gps signal receiver
The gps signal receiver captures the signals of the satellites to be tested selected according to a certain satellite altitude cut-off angle, and tracks the operation of these satellites, transforms, amplifies, and processes the received GPS signals to measure the gps signals. From the satellite to the antenna's propagation time, the navigation message sent by the gps satellite is interpreted and the three-dimensional position, even three-dimensional velocity and time of the station are calculated in real time.
The gps signal receiver hardware and in-house software and gps data post-processing software packages constitute a complete gps user equipment. The structure of the gps signal receiver is divided into two parts: an antenna unit and a receiving unit. For geodesic receivers, the two units are generally divided into two separate components. During the observation, the antenna unit is placed on the station, the receiving unit is placed in the appropriate place near the station, and the cable is used to connect the two units. A whole machine. Some also make the antenna unit and the receiving unit into a whole, and place it on the measuring station when observing.
Under normal circumstances, the gps signal receiver can be powered by direct current charging. At the same time, in order to protect a series of data stored in the device and to minimize the power shortage during operation, it can also use an external battery to provide power. For example, the most common lithium battery.