Electromagnetic wave system (ES) uses electromagnetic wave as detection signal. The label of electromagnetic wave system is small and cheap, which can be demagnetized repeatedly, but it is easily affected by magnetic or metallic substances and produces false positives. Although it is produced almost at the same time as the RF system, its acceptance in the market is not high because of the price and technology.

The electromagnetic system is mainly composed of anti-theft antenna, degausser and magnetic stripe. The magnetic stripe detector is also assisted.

Anti-theft antenna: divided into transmitting end and receiving end. Both the transmitting antenna and the receiving antenna are wound with enameled copper wire, and then put into a frame made of non-interference material (so-called probe gate channel).

The coil of the transmitting antenna is wound with thick copper wire, and then it is connected to the transmitting magnetic field circuit part inside the host through signals, and AC fixed voltage is added to generate AC in the coil, releasing a magnetic field with a certain intensity.

The receiving antenna is mainly used to receive magnetic field signals. Because the internal current is weak, it is wound with thin copper wire, which is generally lighter than the transmitting antenna. It is also connected to the receiving magnetic field circuit of the host through a signal line, and the received chaotic magnetic field and magnetic stripe signals are sent to the internal circuit for screening.

Working principle of electromagnetic system: The digital detector is composed of two antennas, forming a closed-loop magnetic field. When the detected object (such as books and commodities) passes through the channel, the magnetic stripe tag inside will vibrate with the same frequency in the closed-loop magnetic field formed by the channel, and at the same time, it will also generate a higher harmonic with a fixed frequency (usually several times the frequency of the magnetic field), commonly known as magnetic stripe signal.

The magnetic stripe signal will produce an alarm response after being processed by the receiving line, while the usual interference signal will be attenuated after being shielded by the internal line, so there will be no response.

The receiving line of the digital detector is set to dual-frequency reception, one receives the magnetic stripe signal and the other receives the strong interference signal that cannot be shielded by the internal line. Because interference signals usually appear in the form of short-time pulses (from a few seconds to more than ten seconds), the line automatically turns off the receiving line when it receives such interference signals, and automatically turns on after the interference has passed, restoring the normal start-up state. (Improve anti-interference performance).

Degausser is a new product developed for libraries, supermarkets and pharmacies to use composite magnetic strips for anti-theft detection.

The back detector is an instrument to detect whether there is a magnetic stripe in the book.

Working steps of book anti-theft system:

(1) Stick the magnetic stripe, a consumable specially used for anti-theft of books, in the gaps of books.

② Install anti-theft antenna for books in the borrowing channel or the main entrance and exit of the library.

(3) Books that normally go through the borrowing formalities are invalidated by special degaussing equipment or delivered from the anti-theft antenna side, and the borrowing is completed.

(4) When the books (books with magnetic stripes) that have not gone through the normal procedures pass through the exit, the book anti-theft antenna will detect the books that have not been degaussed and give an audible and visual alarm, and the borrower will go through the borrowing procedures again.

Working mode and equipment selection of book anti-theft system;

(1) the separation between books and people:

When the reader chooses the required books and goes through the borrowing formalities at the borrowing desk, the librarian will hand out the books selected by the reader from the side of the anti-theft system after borrowing registration. Books don't go through the anti-theft system. Readers go through the anti-theft system directly after completing the formalities, and then take the books from the anti-theft antenna side.

This way of working is characterized by:

(1) The workbench is near the anti-theft equipment or simply near the anti-theft equipment, and the workbench is at the door;

② Anti-theft consumables are cheap and do not need degaussing;

Selection of anti-theft equipment: single (double) anti-theft antenna+permanent magnetic stripe (recommended 12 or 16 cobalt-based permanent magnetic stripe).

(2) degaussing loading method (general entrance and exit method):

When the reader goes through the borrowing formalities, the librarian removes the magnetism of the book through degaussing equipment, and the reader takes the degaussed book through the anti-theft system. If he has any books with abnormal procedures, the anti-theft system will call the police.

This way of working is characterized by:

① The workbench is far from the exit of the reading room;

② Consumables need corresponding degaussable magnetic strips and degaussing equipment;

Selection of anti-theft equipment: single (double) anti-theft antenna+charging degaussing device (or degaussing plate)+charging degaussing strip (12 or 16 cobalt-based charging degaussing strip is recommended).

If it is necessary to detect the existence of magnetic stripe in the book when returning it, you can choose a detector.

Brief introduction of electronic anti-theft system in shopping malls and supermarkets.

Now the electronic anti-theft system-EAS, the mainstream is divided into: RF system, radio system, acoustic and magnetic system!

Today, with the development of science and technology and the emphasis on efficiency, it is no longer appropriate for retail stores to monitor the traditional anti-theft way of shopping malls by manpower, and it will be replaced by the application of high-tech electronic commodity anti-theft system.

Theft of retail goods is a common problem in the world. According to foreign statistics, if a commodity is only $9, it needs $849 to recover the loss. I lost 34 yuan. The loss of commodities undoubtedly increases the burden on enterprises. Therefore, loss prevention has gradually attracted the attention of domestic enterprise leaders.

As early as the late 1960s, the first electronic article surveillance system EAS appeared in the United States. It fundamentally changed all previous anti-theft measures for customer monitoring. The implementation of anti-theft monitoring on goods has avoided the resistance of consumers, and this anti-theft and deterrent effect has been recognized by many retailers. At present, most large retail enterprises in the world use electronic anti-theft devices. Electronic article monitoring began to enter Asian countries, Japanese, Singaporean, Korean, Hongkong and Taiwan Province provinces as early as 10 years ago, and its installed capacity is also increasing year by year. After 1990s, enterprises in China accepted the electronic anti-theft system, and electronic goods monitoring was installed in shopping malls in commercial developed cities such as Beijing, Shanghai, Guangzhou and Shenzhen.

After 30 years of development, the electronic anti-theft system has developed from a single principle and a single product to a variety of different principles, meeting the needs of different types of stores such as department stores, supermarkets and specialty stores.

If the electronic anti-theft system is subdivided from the form of protection, it can be divided into vertical system, hidden system and channel system.

The detection device of vertical system stands conspicuously at the entrance and exit of shopping mall, which has obvious deterrent effect besides detection function.

The hidden system is to hide the system under the carpet or ceiling of the exit, which will not affect the overall environment of the store, but also play the role of anti-theft protection, and meet the dual needs of shopkeepers for beauty and anti-theft.

Channel system is an effective way to realize supermarket anti-theft. By connecting electronic goods monitoring and cashier at the supermarket exit, channel protection is formed.

According to the detection signal mode, it can be roughly divided into radio system, electromagnetic wave system, microwave system, frequency division system, intelligent system and acoustomagnetic system.

Acoustical magnetic system

The tuning fork will only cause * * * vibration if the oscillation frequency is the same. Acousto-magnetic system (Acousto-magnetic) has realized almost zero false alarm by applying this physical principle. When the acousto-magnetic system tag fixed on the commodity enters the detection area of the system, it will generate * * * vibration, but it will give an alarm only after the receiver receives the * * * vibration signal for four consecutive times (once every 1/50 seconds).

Acousto-magnetic system is characterized by high anti-theft detection rate, almost zero false alarm, good anti-interference, and the width of protection exit can reach 3. 5 meters. There are two kinds of anti-theft labels, which can protect most kinds of goods in shopping malls and can be degaussed repeatedly. Even at the POS cash register, the system can still work normally.

Acousto-magnetic system includes vertical system, channel system and concealed system. There are many models of 10 to choose from, which can be widely used in department stores, supermarkets, specialty stores, video stores, grocery stores, pharmacies and office buildings.

Radio system

Radio frequency (RF) uses radio waves as transmitting and receiving signals, and the detection frequency ranges from 7. X to 8. X megahertz. The biggest advantage of wireless system is its low cost and convenient installation. However, because its anti-theft tag is a ring coil type, the system is easily disturbed by some items, such as electronic products such as cash registers and metal objects. , resulting in false alarm or no alarm.

The radio system has two kinds of labels, soft and hard, which can protect most items in shopping malls. The distance between the two brackets is generally not more than 0.9 meters, which is usually used in shopping malls with only one entrance and exit. There are two kinds of radio systems, vertical and tunnel, which are used to protect department stores, clothing stores and supermarkets.

Electromagnetic wave system

Electromagnetic wave systems use electromagnetic waves as detection signals.

The tag of electromagnetic wave system is the smallest, and the tag price is cheap. It can be demagnetized repeatedly, but it is easy to be affected by magnetic or metallic substances and produce false positives. The width of the protective exit is generally about 0.9 meters. The system will not affect magnetic objects (such as audio tapes, video tapes and magnetic cards).

The new generation channel electromagnetic wave system is an electronic anti-theft system controlled by software, which adopts digital processing technology and integrates with degaussing system, cashier monitoring and closed-circuit television monitoring system. The fast degaussing board can be used for repeated degaussing, and the system cost is high. There are two kinds of electromagnetic wave systems: vertical and channel. The application environment is mostly in libraries, bookstores, musical instruments, hotels, supermarkets and so on.

Microwave system

Microwave system uses microwave as detection signal, which is not easily disturbed by the surrounding environment. It can be installed flexibly and concealed (for example, hidden under the carpet or hung on the ceiling), and has the advantages of being suitable for decoration and beauty in the store. However, due to its wide application range, it is impossible to arrange goods in a certain area, which will limit the use space of businesses with land and money, so it is suitable for large department stores, music stores and fashion stores with large storefronts.

Radio frequency system-frequency division system

Frequency division system is an anti-theft system using high-tech frequency division technology and ultra-low frequency radio wave signals. When the anti-theft tag enters the detection area, the tag receives the signal from the transmitter, divides it into two halves, and then sends the information divided into two halves to the receiver. Only when the receiver receives half of the signal will it give an alarm, which can effectively avoid the interference of other radio waves.

The system has the advantages of light label, small size, low price, stable performance, high detection rate, good anti-interference, and not easy to cause false positives. Products are divided into two types: vertical and hidden. It is an ideal anti-theft system for clothing stores.

Intelligent system

Intelligent system uses unique technology, which is controlled by integrated circuit, driven by battery, and integrated with hard tag and alarm group. When the label is pried or taken out of the mall with the goods, the system will automatically alarm.

The system can protect the goods in the whole shopping mall, and the labels can be reused without damaging the goods. Used to protect valuables, such as fashion, leather, fur, etc.

Fault principle system

The anti-theft system that breaks this principle is a hard tag or magnetic lock. There is ink in the hard label. When a thief tries to take off the hard label, the hard label will spray ink, polluting the goods and the thief's body. Electromagnetic locks are extremely difficult to remove, and forced removal will damage the goods. Convenient use, good deterrent effect and low cost. It is used in clothing, glasses, jewelry, ties, silk fabrics and other commodities. Labels can be reused.

In addition to the anti-theft system of electronic products, there are also closed-circuit television (CCTV) closely related to anti-theft in shopping malls. Closed-circuit television monitoring system can monitor the situation in shopping malls and find suspicious events, which can play a deterrent role. Compared with the electronic anti-theft system, its advantage lies in that it can not only effectively monitor the situation in the shopping mall, but also record the incident or theft process through video tape as the basis for tracing and collecting evidence in the future. Conditional shopping malls can combine electronic anti-theft system with closed-circuit television, which can effectively prevent internal and external thieves from committing crimes, improve the anti-theft effect and reduce the loss of retail goods.

TAG POINT is a manufacturer of electronic anti-theft system with many years of experience. In order to better serve the demand of the fast-growing retail industry in China for anti-theft, Beijing Weitai Company represented the sales of this product in China. Over the years, based on the principle of serving the retail industry in China and keeping pace with the development of the retail industry, we have extensively contacted domestic and foreign retail enterprises, provided anti-theft devices such as commodity anti-theft systems for many domestic enterprises, and actively promoted advanced anti-loss measures and management methods to the domestic retail industry, which won the recognition of enterprises.

At present, the most commonly used anti-theft principle is magnetic induction principle. Generally speaking, it is to spray or paste magnetic things on goods. The waiter will remove the magnetism when buying. If it is not removed, when the goods pass through the security door, the magnetic induction line will be cut in the magnetic induction area of the door and the current induction device of the door will be electrified. At this time, the door will ring, which is an alarm. Of course, in addition to the principle of magnetic induction, there are other things that ordinary supermarkets can't use. Because the cost is too high, even the most common and cheapest magnetic induction is not available in every commodity, and there is still a cost-benefit problem. In addition, some supermarkets will use bar codes that are inherently magnetic, so that when you buy something, the magnetism can be eliminated at the same time. Note: the anti-theft magnets of many commodities are not installed on the bar code, so don't think that you can steal by tearing the bar code!