According to the application frequency, RFID is divided into low frequency (LF), high frequency (HF), ultra high frequency (UHF), microwave (MW), and the corresponding representative frequencies are: low frequency below 135KHz, high frequency 13.56MHz, super High frequency 860M~960MHz, microwave 2.4G, 5.8G
RFID is divided into passive RFID, active RFID, and semi-active RFID according to the way energy is supplied. Passive RFID read and write distance is near, the price is low; active RFID can provide farther read and write distance, but need battery power, the cost is higher, suitable for long-distance reading and writing applications.
Passive RFID products are the earliest developed products, and they are also the most mature products in the market. For example, bus cards, canteen meal cards, bank cards, hotel access cards, second-generation ID cards, etc., which are everywhere in our daily life, belong to the close-contact type. The main working frequency of its products are low frequency 125KHZ, high frequency 13.56MHZ, ultra high frequency 433MHZ, ultra high frequency 915MHZ.
Active RFID products have been slowly developed in recent years, and their long-distance automatic identification characteristics determine their huge application space and market potential. In the field of remote automatic identification, such as smart prisons, smart hospitals, smart parking lots, intelligent transportation, smart cities, smart earth and Internet of Things, there are major applications. Active RFID has sprung up in this field and belongs to the category of remote automatic identification. The main working frequency of the product is UHF 433MHZ, microwave 2.45GHZ and 5.8GHZ.
Active RFID products and passive RFID products have different characteristics, which determine different application areas and different application modes, and also have their own advantages. However, in this system, we focus on the semi-active RFID product between active RFID and passive RFID, which combines the advantages of active RFID and passive RFID, and manages the access control in the access control. , regional positioning management, perimeter management, electronic fences and security alarms and other fields have great advantages.
Semi-active RFID products, combined with the advantages of active RFID products and passive RFID products, enable the microwave 2.45G to take advantage of the low frequency 125KHZ frequency. Semi-active RFID technology, also known as low-frequency activation trigger technology, uses low-frequency close-range precise positioning, microwave remote recognition and uploading data to solve the functions that pure active RFID and passive RFID cannot achieve. Simply put, it is to activate the positioning in close proximity, to identify and upload data from a distance.