RFID belongs to the perception layer of the Internet of things, belongs to the terminal device, and is used to provide / perceive object numbers and information.
The Internet of things (IoT) is a distributed system that connects many RFID application systems and identifies objects in the wide area network through Internet.
Which layers is the Internet of things divided into? From the perspective of technical architecture, the Internet of things can be divided into three layers: perception layer, network layer and application layer.
The sensing layer consists of various sensors and sensor gateways, including temperature and humidity sensors, RFID tags, readers, cameras and other sensing terminals. The function of the perceptual layer is equivalent to the nerve endings of human eyes, ear, nose, throat and skin. It is the source of the Internet of things to identify objects and collect information. Its main function is to identify objects and collect information.
RFID (Radio Frequency Identification) is a non-contact automatic identification technology, which automatically identifies the target object and obtains the relevant data through the radio frequency signal. The identification work does not need human intervention and can work in a variety of environments. RFID technology can identify multiple tags at the same time, and the operation is fast and convenient. Short-distance RF products are not afraid of oil stains, dust pollution and other harsh environment, in such an environment instead of bar code, such as used in the factory assembly line to track objects. Long-distance radio frequency products are mostly used in traffic, the identification distance can reach dozens of meters, such as automatic weighing or earthwork vehicle counting and so on.
The basic components of RFID, the most basic RFID system consists of three parts:
Tags: composed of coupling elements and chips, each tag has a unique electronic code and is attached to the object to identify the target object.
Reader: a device that reads (and sometimes writes) tag information, which can be designed as hand-held or fixed, integrated or multi-antenna.
Antenna: the radio frequency signal is transmitted between the tag and the reader, and the linear polarization is divided into circles.
Electronic tags generally keep electronic data in a fixed format. In practical applications, electronic tags are attached to the surface of the object to be identified. The reader can read and recognize the electronic data stored in the electronic tag without contact, so as to achieve the purpose of automatic recognition.
The basic working principle of RFID technology is that the reader sends out a certain frequency radio frequency signal through the antenna, generates induced current when the tag enters the radio frequency magnetic field to obtain energy, and sends out its own coding and other information to be read and decoded by the reader and sent to the host computer for relevant processing.