source:truck tracking webfleet solutions release time:2022-12-29 Hits: Popular:realtime gps tracker online

At the end of the 1950s, the former Soviet Union launched the first man-made earth satellite of mankind. American scientists discovered the phenomenon of Doppler frequency shift in their tracking and research, and used this principle to promote the establishment of the Doppler satellite navigation and positioning system TRANsIT, which has achieved great success in military and civil aspects. It is a leap in the history of navigation and positioning. China has also introduced several Doppler receivers, which are used in island joint survey Earth exploration and other fields. However, due to the low orbit height and signal carrier frequency of the Doppler satellite, it is difficult to improve the orbit accuracy, which makes the positioning accuracy low to meet the requirements of geodesy or engineering survey, and it is impossible to apply it to the research of astrogeodynamics. In order to improve the accuracy of satellite positioning, the United States began to build the Global Positioning System (GPS) in 1973. After entering the phase of scheme demonstration and system test, the official working satellite was launched in 1989, and was completed and put into use in 1994. The space part of the GPS system is composed of 21 satellites, which are evenly distributed on 6 orbital planes. The ground height is more than 20000 km, the orbital inclination is 55 degrees, the flat heart rate is about 0, and the period is about 12 hours. The satellite transmits carrier signals of two bands to the ground. The carrier signal frequencies are 1575.442 MHz (L1 band) and 1227.6 MHz (L2 band) respectively. The satellite is equipped with atomic clocks with high accuracy to ensure the stability of the frequency, The broadcast ephemeris representing satellite position, C/A code and P code used for ranging, and other system information are modulated on the carrier wave, which can provide high-precision, all-weather, continuous, real-time three-dimensional velocity measurement, three-dimensional positioning, and time service to any number of users worldwide.
The control part of the GPS system consists of five monitoring stations located in the United States. These stations continuously observe the GPS satellites and update the calculated and predicted information from the injection station to the satellite information.
Read recommendations:
Student GPS real-time positioning products.plug & play Obd gps tracker manufacture
Next article:International GPS development
Related Information
personal gps tracker distributors
2023-03-16mini gps tracker manufacture
2023-04-23GPS Tracker Solution
2023-04-11simple gps tracking custom
2023-04-23Gps speed limiter company
2023-04-23Gps speed limiter distributors
2023-04-234G GPS Tracker manufacturer
2023-04-23SecumoreGPS
2023-03-16GPS Trackers wholesale
2023-04-11fleet gps trackers custom
2023-04-234G Wired GPS Tracker PCBA
2022-06-17P02L Smart Walkie-Talkie Tracker
2025-09-19G200(L) -Magnet GPS Tracker
2022-06-20G07L 4G GPS Tracker
2022-09-06VSL100 GPS Speed Limiter, Speed Governor
2022-06-19Vehicle GPS navigator development.gps tracker with magnet Production
2023-05-18Automobile GPS Global Positioning System
2022-12-09What should I pay attention to when buying GPS products?
2022-08-10GPS automatic gain control system
2022-11-17Overview of GPS Vehicle Positioning System
2022-07-12Origin of GPS development
2022-12-29How to purchase GPS.gps tracker with magnet distributors
2023-08-25Six characteristics of GPS
2022-10-12GPS positioning mode
2022-10-22The Development History of GPS in the United States.4G GPS Tracker for vehicles manufacture
2023-08-19Which is the best use of GPS positioning tracker for the loss of the elderly
2023-02-17GPS addressing locator
2023-07-27Dual GPS frequency positioning, improve accuracy.Portable car gps systems distributors
2023-03-11gps vehicle tracker.What's wrong with the inaccurate positioning of the ultra long standby GPS locat
2023-10-11Anti -theft installation and operation introduction of automobile car GPS positioner.gps tracker no
2023-04-04