EAS function application of UHF RFID electronic tag

1. Overview of Traditional EAS System

With the continuous improvement of people's living standards and the continuous evolution of lifestyles towards leisure and comfort, in shopping malls, bookStores, libraries and other occasions, open-shelf sales and open-shelf borrowing have become the main means for people to shop and borrow. It serves as a major means to improve service quality and economic benefits. But the ensuing problem is: the loss of goods and books has become a headache for merchants, which seriously damages the interests of merchants, makes the profits of merchants lose in vain, and even leads to the closure of shopping malls. How to prevent commodity theft and protect the interests of merchants has attracted the attention of more and more retailers. In this context, the EAS system is gradually recognized and accepted by the majority of merchants, and its application in shopping malls, libraries and other fields is also becoming more and more extensive.

EAS (Electronic Article Surveillance), also known as Electronic Article Surveillance System, is one of the commodity security measures widely used in the Retail Industry. It is a high-tech electronic anti-theft device. It uses high-tech means to endow commodities with a self-defense capability, which can effectively protect commodities and prevent them from being stolen. In foreign countries, 90% of the retail industry adopts the EAS system to reduce the theft rate. In China, the EAS system has gradually been accepted and adopted by the majority of merchants. EAS system is the most reliable and economical high-tech management method to reduce theft and loss.

A typical EAS system generally consists of three parts, 1) electronic sensor attached to the product; 2) electronic sensor control device, so that the authorized product can enter and exit normally; 3) monitor, which has a certain radiation within a certain area of the exit Surveillance space.

The working principle of the EAS system is: in the surveillance area, the transmitter transmits signals to the receiver at a certain frequency. Transmitters and receivers are generally installed at the entrances and exits of retail stores and libraries to form a certain monitoring space. When a tag with special characteristics enters the area, it will interfere with the signal sent by the transmitter, and this interference signal will also be received by the receiver, and then analyzed and judged by the microprocessor, it will control the sound of the siren.

According to the detection signal method of application, it can be divided into different types such as radio system, electromagnetic wave system, microwave system, frequency division system, intelligent system and acousto-magnetic system. At present, the EAS system has also been widely used in major shopping malls, bookstores, and libraries in China. Its basic working principle is as follows:

(1) Attach the magnetic strip to the product.

(2) Install detectors at the exit passages of shopping malls.

(3) After the authorized product passes through the special degausser to degauss the magnetic strip, the magnetic strip becomes invalid.

(4) When unauthorized goods (not degaussed) pass through the exit, the Access Control detector detects and sends out an alarm to intercept the goods from going out.

2. The attention of RFID technology to EAS

With the continuous advancement of technology, in recent years, especially in the past five years, the application of Internet of Things technology has achieved rapid development, especially in the fields of warehousing and logistics, Intelligent transportation, etc., the Internet of Things has demonstrated strong technical strength and vitality. As one of the main technologies of the Internet of Things, the application of RFID technology has attracted more and more attention. As an upgrading technology of barcode, RFID technology has incomparable advantages of barcode, such as multi-target identification, long-distance identification, confidentiality, etc., and will not repeat them here.

As a supporting EAS technology developed together with barcodes, what role should it play in the RFID era? Should it continue to exist intact? Disappear? Or keep up with the pace of RFID technology and keep pace with the times? First of all, it is certain that: As an effective anti-theft technology in shopping malls, EAS will not end its historical mission because of the withdrawal of barcodes. Combining with RFID technology, an EAS technical solution based on RFID technology is proposed. On the basis of traditional EAS, this technology stores anti-theft information in RFID electronic tags, and achieves the purpose of commodity anti-theft through the identification of electronic tags.

3. Application analysis of UHF electronic tag EAS function

RFID is classified according to frequency, including low-frequency, high-frequency, ultra-high-frequency, microwave and other RFIDs, each of which has its own strengths in different application fields. This article only describes the EAS technology involved in the ultra-high frequency (UHF) RFID, which has broad application prospects in the fields of warehousing, logistics, retail, Library management, and intelligent transportation.

Taking large-scale retail applications as an example, if UHF RFID technology is used for fast commodity entry and exit management, while the original EAS system is used for entry and exit monitoring, it will inevitably cause two systems to exist at the same time, not to mention waste, but also to management. Bring difficulties and increase the operating costs of businesses.

Because the ISO18000-6C agreement does not stipulate the relevant standards of EAS, different electronic label chip design companies have different considerations in the design of EAS. This article takes NXP's second-generation RFID chip as an example to briefly introduce the EAS working principle of the RFID electronic tag chip.

1. Registration of electronic tags

Before using the electronic tag, it needs to be registered. Registration is the process of writing the basic information of the item to be attached to the electronic tag and entering the information into the database. There is a special read-write EAS bit in each electronic tag, which can only be modified by specific commands. During the tag registration process, the EAS bit is set at the same time. Refer to Figure 1 for the setting process of the EAS bit.

2. Product delivery

Before the goods with electronic tags leave the warehouse, it is necessary to use the reader to send a special command to clear the EAS bit in the electronic tag. Only commodities that have completed this step can safely pass through the export detection device. Taking book borrowing as an example, when readers select a book and need to borrow it, they can go through the borrowing procedures on the self-service borrowing and returning machine, and the self-service borrowing and returning machine will automatically clear the EAS bit. Readers can pass through the detection door safely. If you do not go through the borrowing procedures, there will be an audible and visual alarm when you pass through the detection door. The monitoring flow chart is as follows:

At present, there are more and more companies that can provide UHF RFID electronic tags. Different companies' electronic tags have different definitions and access methods for EAS bits. When designing EAS for different RFID electronic tags, it is first necessary to know their access instructions. There are also RFID electronic tags provided by companies that do not have a dedicated EAS bit. For this type of tag, if you want to use the EAS function, what should you do? The usual practice is to open up 1 or more data bit simulations in the EPC area or user data area. EAS function, specific location and size can be defined according to development needs. When the EAS function is required, a specific value can be specified for the specific position. When the monitoring module reads the electronic tag, it first analyzes the EAS bit, and drives an alarm when an abnormality is found. However, using this analog EAS function is usually less efficient than a dedicated EAS function.

Four. Summary

The traditional retail industry and other fields mostly adopt the sales management mode of barcode plus EAS. With the popularization and application of RFID technology in the retail industry and other fields, it will definitely bring innovative changes to the industry. At the same time, because the RFID technology itself considers the EAS function, in many places where RFID technology is applied, the EAS function can be easily realized, the management is simplified, and the cost is reduced. It is a high-grade shopping mall, large and medium-sized supermarket, library, etc. Iconic equipment with technological content is an inevitable trend in the development of modern retail and other fields.