Bar code automatic identification technology

Barcodes for short are composed of a group of black-and-white stripe symbols with different thicknesses. Barcodes contain numerical information, letter information, logo information and symbol information, which are mainly used to indicate the name, origin, price, type, etc. of goods, and are a common method of expressing commodity codes all over the world. The stripes of the two-dimensional bar code are composed of a group of black stripes with different widths and different reflectivities and white spaces according to the prescribed coding rules.

Radio Frequency ldentification

Radio frequency technology is a communication technology based on electromagnetic theory, which uses radio waves to read and write the recording medium. The advantage of radio frequency system is not limited to sight line, and the recognition distance is farther than that of optical system. The distance of radio frequency identification can reach tens of centimeters to several meters, and thousands of bytes of information can be input according to the way of reading and writing, at the same time, it also has extremely high confidentiality. The application fields of RFID technology are material tracking, vehicle and shelf identification and other occasions requiring non-contact data acquisition and exchange, especially those requiring frequent changes in data content.

Global Positioning System

Global Positioning System (GPS) is a new-generation satellite navigation and positioning system with all-round real-time three-dimensional navigation and positioning capability in sea, land and air, and it has the remarkable characteristics of all-weather, high precision, automation and efficiency. The GPS is made up of 24 satellites launched by the U.S. Department of Defense, which are distributed around the Earth in 6 orbits with a height of 20,000 kilometres. Each track has 4 satellites, and at any point on earth, it is possible to receive signals from 4 satellites at any one time. In other words, GPS satellites emit space orbit information covering the entire Earth's surface.