Asסס they cross a check point by detecting tags or label that resonate with: -- Radio Frequency field in RF systems

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1 ELECTRONIC ARTICLE SURVEILLANCE Overview EAS: Shrinkage accounts for any loss of inventory due to shoplifting, employee theft, administrative error or vendor fraud. Sources of retail shrinkage are: shoplifting (41.2%), employee theft (36.5%), internal error (16.5%) and suppliers/vendors (5.8%). Among the most stolen items include cosmetics and skin care, alcohol, women s wear/apparel, perfume and designer wear. Electronic Article Surveillance, like other loss prevention technologies like CCTV has significantly helped reduce the part relative to the shoplifting, mainly as a dissuasive factor as no EAS system can be 100$ proof. EAS has actually 3 different approaches in monitoring the articles in shops, book shops, pharmacies, libraries, : Asסס they cross a check point by detecting tags or label that resonate with: -- Radio Frequency field in RF systems -- An Acousto-magnetic field in AM systems -- An Electromagnetic field in EM systems Asסס they cross a check point by identifying RF labels with unique ID in RFID systems Whileסס they are on their shelves by hooking them to a wired system that would signal any attempt to detach the article from its connection. Bothסס at the shelf and at the exit using the 3 Alarm tags that would sound off the alarm if ever removed by force from the article, moved across the antennas at the exit, and continue to sound even after it leaves the shop for several minutes. Or simply by using Ink Tags that would break and permanently damage the ornament it was tagged to if ever removed by force inside or outside the shop. Not to forget that some articles are better protected inside safes or tied with Wraps or simply tangled with metal wires. Note that Source Tagging provides a positive return on investment for retailers by shifting the application process of labels and disposable hard tags to the supplier who can apply these security devices more efficiently and consistently. Additional benefits for retailers include: -- Reduced in-store labor costs, -- Increased focus on the customer -- Improved merchandising opportunities -- Reduced out of stocks -- Increased speed of products to selling floor to drive increased sales. The following article will shed some light on the above 4 different systems. Swept Radio Frequency (8.2MHz) Technology: RF systems transmit a signal that varies between 7.4 and 8.8 MHz with a center frequency of 8.2 MHz (often described simply as the bandwidth ). The label consists of an induction coil and a capacitor in circuit, each of which store electrical energy. When entering an Electro Magnetic Field a current is induced in the coil which builds charge in the capacitor. When the energy in the coil and capacitor are matched they will resonate. The design of the label requires the circuit to be chemically etched into aluminum foil forming the coil and capacitor and then embedded onto paper. To deactivate the 51

2 label a device is used that is very similar to the transmitter, except that it creates a stronger field. The higher level of power in the label causes the capacitor to short, similar to a fuse in a common appliance except in reverse. The size of the label is important for performance reasons. The standard size of label is 4 x 4 cm label sizes smaller than this have different performance characteristics. Different hard tags are available; and the circuit within them is exactly the same as the label, with the exception that a copper winding and proper capacitor are used. In line with the general rules of EAS, larger hard tags do give improved exit spacing to RF systems; however, at these increased distances RF labels will not be detected. Due to the frequency used by RF systems, there are strict installation guidelines that should be followed to ensure they are effective in the field. Of particular concern for these systems is electrical noise. Vertical power cables, neon lights, etc, can all very badly affect the performance of the system. Passive noise sources are also a major issue. RF systems cannot be installed near metal doors and even the metal edging around door mats. Nevertheless, new improved noise reduction filtering and the 360 radio frequency technology employing a rotating RF field have vastly improved tag detection, regardless of the type of tag or the angle at which it is carried through the system, supporting wider aisles, and providing more flexibility in terms of store layout. Note that RF systems exist as mono-antennas combining in one pedestal the transmitter and the receiver, and could be fitted with counters to log on a PC the number of people entering and leaving the premises. As a rule of thumb the maximum opening for RF hard tags is 220cm while for 4x4 labels is 180cm.

3 Acousto-Magnetic (58 KHz) Technology: As the latest EAS technology, AM can achieve very wide exit detection combined with small tags and labels, and greater detection performance against shielding. AM systems create a detection zone by transmitting at 58 khz. This transmitted signal is not continuous but sent in bursts, or when a tag or label enters the detection zone it is energized by the transmit pulse, when the transmit signal ends the label or tag responds by sending it s own 58kHz signal. Like a tuning fork, the signal will decay or ring-down (reduce in amplitude after the initial response). When the transmitter is off between transmitted pulses, the receiver listens for a signal from the tag. The receiver has a very narrow bandwidth (600 Hz). The received signal is processed by the receiver to ensure that the signal occurs at the right time and at the correct repetition rate, further confirmed a number of times before triggering an audible alarm or alarm activity. The ability of the system to detect smaller labels and to use a very narrow bandwidth comes from the design of the tag and label. The AM tag or label contains two elements within a three dimensional plastic housing consisting of amorphous resonator material with magnetic properties and a bias magnetic strip. When aligned on top of the magnet, the amorphous material vibrates at a defined frequency. The frequency of the tag is dictated by the length of the strip. Deactivation of the AM label is carried out by (degaussing) the magnet, a process that does not rely on complex design within the label -- only on the magnetic properties of the bias magnetic strip. This simple operation shifts the frequency of the label outside the detection window and can be carried out repeatedly, enabling the label to be turned on and 7 off within the supply chain any number of times. As a rule of thum, the maximum opening for AM tags is 250cm while the AM labels is 190cm. Acousto-Magnetic

4 Electromagnetic (200Hz) Technology: The electromagnetic EAS system creates a low frequency electromagnetic field (fundamental frequencies between 70 Hz and 1 khz are typically used) between two pedestals at an exit or checkout aisle. The field continuously varies in strength and polarity, repeating a cycle from positive to negative and back to positive again. With each half cycle, the polarity of the magnetic field between the pedestals changes. In response to the changing magnetic field created by the transmitter, the magnetic field domain of the tag material abruptly switches as the field strength varies past a particular point, whether positive or negative, during each half of the transmit cycle. This abrupt change in the magnetic state of tag material generates a momentary signal that is rich in harmonics (multiples) of the fundamental frequency. Using electronic signal processing techniques, the system identifies that the harmonics are at the right frequencies and levels, and that they occur at the proper time in relation to the transmitter signal. If the criteria are met an alarm occurs. EM labels are the slimmest of all labels and hence can be easily hidden in books or pharmaceutical boxes Unlike with the RF technology, the EM allows the labels to be alternatively activated and deactivated over and over again, while in the RF a deactivated label cannot be reactivated. This feature makes the EM system adequate for libraries where books are to be borrowed and returned. As a rule of thum, the maximum opening for EM strips is 120cm. Systems and Equipment cannot be reliable unless properly maintained by professionals on a yearly basis

5 Radio Frequency Identification RFID (13.56Mhz) Technology: As the same time retailers are investing in EAS they are looking for integrated, datadriven in-store solutions that can help them measure, manage and, ultimately, improve store operations. Currently retailers are increasing their investments in solutions that don t just reduce shrink, but also provide additional capabilities like remote diagnostics and service, operations applications such as store traffic counting, exception-based reporting with integrated digital CCTV that identifies areas of higher inventory losses (including employee theft), and cashier training issues or improper EAS tagging procedures. Many of these integrated solutions will be based on EAS infrastructures. The retail market is not homogeneous and customers will require a range of EAS and RFID solution sets. There is no single migration path from EAS to RFID. Rather, we foresee different needs-based scenarios where some retailers can benefits from combined EAS-RFID functionality whereas others may require a sequential approach. Depending on the existing infrastructure, a migration path would consider the following factors: Breadthסס of the RFID implementation Priceסס and velocity of items to be tagged Costסס of EAS versus RFID tags Frequencyסס of out-of-stock events Abilityסס of retailer s information infrastructure to manage the increasing flow of RFID data this applies to articles that were paid for in shops, or books that were borrowed, Or even if the checking is done at the counter then the system could eventually be used to identify the articles so as to charge the carrier for the total cost of the moved articles Recommendations Different EAS systems are suitable for different applications; nevertheless, which ever system one chooses one must clearly inform that the area is protected by an EAS system, as half of the theft could be eliminated by the disuation effect. Moreover, wide openings could be a nuisance, unless 3 alarm tags are used, as in case of alarm and multiple people are crossing the aisle, then the security guard will not bother everyone to find the thief and hence will let him go. The following devices can create or absorb noise signals which can reduce the performance of an EAS system: EASסס systems installed in other shops (even if they are installed up to 100m or more away from your store). Anyסס electronic device that operates around the same frequency or produces harmonic frequencies around that frequency. ( Moving )סס Objects containing metal, like sliding and revolving doors, elevators, Electronic devices, like computers, laptop screens, LCD screens, cash registers, engines, transformers, etc. Verticallyסס positioned power cables, both low voltage and high voltage. halogen, Lightsסס (flashing, fluorescent, gas-de-charge, etc.) A sophisticated anti-collision algorithm is also included to enable up to 25 items to be read within a second, which allows the system to identify multiple articles crossing the antennas at the exit, and allow the system to differentiate between the articles that are allowed access and others that are not; and