RFID-enabled deactivation system and method for AM ferrite-based tags

Abstract

A system and method for deactivating a marker including an electronic article surveillance ("EAS") component and a radio frequency identification ("RFID") circuit. The method includes: receiving, by an RFID element of the marker, an RFID deactivation signal transmitted from an external device; and supplying power from the RFID element to an EAS demodulator element in response to the RFID deactivation signal, such that the demodulator element switches from a first state to a second state. When the demodulator element switches from the first state to the second state, a resonant frequency of the marker is changed to a first value that falls outside an operating frequency range of an EAS system. The second state is maintained after power is no longer supplied to the demodulator element.

Description

[0001] This application is a divisional application of a Chinese invention patent application filed on March 4, 2019, with international application number PCT / US2019 / 020504, national application number 201980015580.2, and invention name “RFID-supported deactivation system and method for AM ferrite-based markers”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of U.S. Patent Application No. 15 / 912,190, filed on March 5, 2018, entitled “SYSTEMS AND METHODS FOR RADIOFREQUENCY IDENTIFICATION ENABLED DEACTIVATION OF ACOUSTO-MAGNETIC FERRITEBASED MARKER,” the contents of which are incorporated herein by reference in their entirety. Background Art Technical Field

[0004] The present disclosure relates generally to radio frequency identification ("RFID") systems. More specifically, the present disclosure relates to implementing RFID-enabled deactivation systems and methods for acoustomagnetic ("AM") ferrite-based tags.

[0005] Description of related technologies

[0006] A typical electronic article surveillance ("EAS") system in a retail setting may include a monitoring system and at least one security tag or marker that is attached to merchandise to prevent unauthorized removal of the merchandise. The monitoring system establishes a surveillance zone in which the presence of security tags and / or markers may be detected. The surveillance zone is typically established at a point of entry to a controlled area (e.g., near an entrance and / or exit to a retail store). If merchandise with an active security tag and / or marker enters the surveillance zone, an alarm may be triggered to indicate that the merchandise may be removed from the controlled area without authorization. Conversely, if the merchandise is authorized to be removed from the controlled area, the security tag and / or marker of the merchandise may be deactivated and / or separated from the merchandise. Thus, the merchandise may be carried through the surveillance zone without being detected by the monitoring system and / or without triggering an alarm.

[0007] The security tag or marker typically includes a housing. The housing is made of a low-cost plastic material such as polystyrene. The housing is typically manufactured with a drawn cavity in a rectangular form. An LC circuit is arranged within the housing. The LC circuit includes a ferrite rod coil connected in series with a capacitor. During operation, the LC circuit generates a resonant signal with a specific amplitude that can be detected by the monitoring system.

[0008] Conventional deactivation processes for EAS security tags or markers are not convenient for self-service checkout or mobile checkout due to the high power and complexity of the deactivation electronics required to deactivate the EAS security tags or markers. Many attempts have been made to find alternative solutions to deactivate EAS security tags or markers, but none have been successful. Summary of the invention

[0009] The present disclosure generally relates to implementing systems and methods for operating a marker. The method includes: receiving, by an RFID element of the marker, an RFID deactivation signal transmitted from an external device (e.g., from a point of sale ("POS") terminal in response to a successful purchase transaction of an item to which the marker is coupled; supplying power from the RFID element to a demodulator element in response to the RFID deactivation signal, causing the demodulator element to switch from a first state to a second state; and / or interrupting the supply of power to the demodulator element. When the demodulator element switches from the first state to the second state, a resonant frequency of the marker is changed to a first value that falls outside an operating frequency range of an electronic article surveillance ("EAS") system.

[0010] In some scenarios, the demodulator element is electrically connected to the LC circuit of the marker. More specifically, the demodulator element is electrically connected in series between the capacitor of the LC circuit and the ferrite rod coil. The demodulator element may include: a magnetic component configured to change the magnetic state from a first magnetic state to a second magnetic state when power is applied to the magnetic component, and remain in the second magnetic state when power is removed; or a switch component configured to change from a closed position to an open position when power is supplied to the switch component, and remain in the open position when power is removed.

[0011] In those or other scenarios, the marker comprises a reusable marker. The reusable marker is configured to: receive an RFID activation signal transmitted from the external device or another external device; and (in response to receiving the RFID activation signal) supply power to a demodulator element so that the demodulator element switches from the second state to the first state. When the demodulator element switches from the second state to the first state, the resonant frequency of the marker is changed to a second value that falls within the operating frequency range of the EAS system.

[0012] In those or still other scenarios, the marker is provided with an energy harvesting element. The energy harvesting element is configured to perform operations to harvest energy from the surrounding environment. The harvested energy is used to enable the operation of the RFID element and the demodulator element. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present solution will be described with reference to the following drawings, wherein like reference numerals refer to like items throughout the drawings.

[0014] Figure 1 is a diagram of an illustrative architecture of an EAS system that includes at least one marker.

[0015] Figure 2 Is adopted Figure 1 Illustration of the data network of an EAS system.

[0016] Figure 3 yes Figure 1 Illustration of an illustrative architecture for the tagger shown.

[0017] Figure 4 yes Figure 3 A diagram of an illustrative architecture of the circuit shown.

[0018] Figure 5 yes Figure 4 Block diagram of the RFID components shown.

[0019] Figure 6 is a flow chart of an illustrative method for operating a tagger. DETAILED DESCRIPTION

[0020] It will be readily understood that the components of the present embodiment as generally described herein and shown in the accompanying drawings may be arranged and designed in a variety of different configurations. Therefore, as shown in the accompanying drawings, the following more detailed description of various embodiments is not intended to limit the scope of the present disclosure, but is merely representative of various embodiments. Although various aspects of the embodiments are presented in the accompanying drawings, unless otherwise indicated, the drawings are not necessarily drawn to scale.

[0021] The present solution may be implemented in other specific forms without departing from the spirit or essential characteristics of the present solution. The described embodiments are to be considered in all respects as merely illustrative and not restrictive. The scope of the present solution is therefore indicated by the appended claims rather than by this detailed description. All changes within the equivalent meaning and range of the claims are to be included within their scope.

[0022] References throughout this specification to features, advantages, or similar language do not imply that all of these features and advantages that can be achieved with the present solution should be or are any single embodiment of the present solution. Rather, language referencing features and advantages should be understood to mean that a particular feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present solution. Therefore, discussion of these features and advantages and similar language throughout this specification may, but do not necessarily, refer to the same embodiment.

[0023] Furthermore, the described features, advantages, and characteristics of the present solution may be combined in any suitable manner in one or more embodiments. In view of the description herein, one skilled in the relevant art will recognize that the present solution may be practiced without one or more specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the present solution.

[0024] Reference throughout this specification to "one embodiment," "an embodiment," or similar language means that a particular feature, structure, or characteristic described in connection with the indicated embodiment is included in at least one embodiment of the present solution. Thus, the phrases "in one embodiment," "in an embodiment," and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

[0025] As used in this document, the singular forms "a", "an", and "the" include plural referents unless the context clearly indicates otherwise. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. As used in this document, the term "including" means "including but not limited to."

[0026] The present solution generally relates to a combined tag or marker that includes both RFID component(s) and AM component(s). The novelty of the present solution is that there is a connection between the RFID component(s) (e.g., RFID chip) and the AM component(s). This connection allows the RFID component(s) to receive messages from a point of sale ("POS") identifying products that have been successfully purchased. In response to these messages, the RFID component(s) perform operations to disable the AM component(s) such that the AM feature of the tag or marker is deactivated.

[0027] Illustrative EAS Systems

[0028] Reference now Figure 1 , a schematic diagram of an illustrative EAS system 100 is provided. The EAS system 100 includes monitoring systems 106 to 112, 114 to 118, and at least one marker 102. The marker 102 can be attached to merchandise to prevent the merchandise from being removed from a commercial facility (e.g., a retail store) without authorization. The monitoring system includes a transmitter circuit 112, a synchronization circuit 114, a receiver circuit 116, and an alarm 118.

[0029] During operation, the monitoring systems 106 to 112, 114 to 118 establish a surveillance zone in which the presence of the marker 102 can be detected. The surveillance zone is typically established at an entry point to a controlled area (e.g., near an entrance and / or exit to a retail store). If merchandise with an active marker 102 enters the surveillance zone, an alarm may be triggered to indicate that the merchandise may be removed from the controlled area without authorization. Conversely, if the merchandise is authorized to be removed from the controlled area, the marker 102 may be deactivated and / or separated from the merchandise. Thus, the merchandise may be carried through the surveillance zone without being detected by the monitoring system and / or without triggering the alarm 118.

[0030] The operation of the monitoring system will now be described in more detail. The transmitter circuit 112 is coupled to the antenna 106. The antenna 106 emits a transmission (e.g., radio frequency ("RF")) pulse train at a predetermined frequency (e.g., 58KHz) and a certain repetition rate (e.g., 50Hz, 60Hz, 75Hz, or 90Hz) with a pause between consecutive pulse trains. In some scenarios, each transmission pulse train has a duration of approximately 1.6ms. The transmitter circuit 112 is controlled to emit the aforementioned transmission pulse train by the synchronization circuit 114, which also controls the receiver circuit 116. The receiver circuit 116 is coupled to the antenna 108. The antennas 106, 108 include N turns (e.g., 100 turns) of closely coupled pickup coils, where N is any number.

[0031] When the marker 102 resides between the antenna 106 and the antenna 108, the transmission pulse train transmitted from the transmitter circuit 112, 106 causes the marker 102 to generate a signal. In this regard, the marker 102 includes a circuit 110 disposed in a marker housing 126. The transmission pulse train emitted from the transmitter circuit 112, 106 causes the circuit 110 to generate a response at a resonant frequency (e.g., 58KHz). Therefore, a resonant response signal is generated whose amplitude decays exponentially over time.

[0032] The synchronization circuit 114 controls the activation and deactivation of the receiver circuit 116. When the receiver circuit 116 is activated, the receiver circuit detects signals at a predetermined frequency (e.g., 58 KHz) within a first detection window and a second detection window. In the case where the transmit pulse train has a duration of approximately 1.6 ms, the first detection window will have a duration of approximately 1.7 ms, and the first detection window will begin approximately 0.4 ms after the end of the transmit pulse train. During the first detection window, the receiver circuit 116 integrates any signals present at the predetermined frequency. In order to produce an integration result in the first detection window that can be easily compared with the integrated signal from the second detection window, the signal transmitted by the marker 102 should have a relatively high amplitude (e.g., greater than or equal to approximately 1.5 nanowebers (nWb)).

[0033] After signal detection in the first detection window, synchronization circuit 114 deactivates receiver circuit 116 and then reactivates receiver circuit 116 during a second detection window, which begins approximately 6 ms after the end of the aforementioned transmit burst. During the second detection window, receiver circuit 116 again looks for a signal with a suitable amplitude at a predetermined frequency (e.g., 58 kHz). Since it is known that the signal emitted from marker 102 will have a decaying amplitude, receiver circuit 116 compares the amplitude of any signal detected at the predetermined frequency during the second detection window with the amplitude of the signal detected during the first detection window. If the amplitude difference is consistent with the amplitude of an exponentially decaying signal, it is assumed that the signal is actually emitted from the marker between antenna 106 and antenna 108. In this case, receiver circuit 116 issues an alarm 118.

[0034] The transmitter circuit 112 and the receiver circuit 116 may also be configured to act as an RFID reader. In these scenarios, the transmitter circuit 112 transmits an RFID interrogation signal to obtain RFID data from the active tag 102. The RFID data may include, but is not limited to, a unique identifier of the active tag 102. In other scenarios, these RFID functions are provided by devices that are separate and spaced apart from the transmitter circuit 112 and the receiver circuit 116.

[0035] Reference now Figure 2 , a schematic diagram of an exemplary architecture of a data network 200 in which the EAS system 100 is employed is provided. The data network 200 includes a host computing device 204 that stores data about at least one of identification, inventory, and pricing of merchandise. The host computing device 204 may include, but is not limited to, a server, a personal computer, a desktop computer, and / or a laptop computer.

[0036] The first data signal path 220 allows two-way data communication between the host computing device 204 and the POS terminal 208. The second data signal path 222 allows data communication between the host computing device 204 and the programming unit 202. The programming unit 202 is generally configured to write product identification data and other information into the memory of the marker 102. Marker programming units are well known in the art and will not be described again herein. Any known or to be known marker programming unit can be used herein without limitation.

[0037] The third data signal path 224 allows data communication between the host computing device 204 and the base station 210. The base station 210 communicates wirelessly with the portable read / write unit 212. Base stations are well known in the art and will not be described herein. Any known or later known base station may be used herein without limitation.

[0038] Portable read / write unit 212 reads data from the tag to determine the inventory of the retail store and writes the data to the tag. When the EAS tag is applied to the merchandise, data can be written to the tag. Portable read / write units are well known in the art and will not be described herein. Any known or to be known portable read / write unit may be used herein without limitation.

[0039] Typically, POS terminal 208 facilitates the purchase of merchandise from a retail store. POS terminals and purchase transactions are well known in the art and therefore will not be described herein. Any known or to-be-known POS terminal and purchase transaction may be used herein without limitation. The POS terminal may be a fixed POS terminal or a mobile POS terminal.

[0040] As should be understood, when the item to which the marker 102 is coupled has been successfully purchased, the issuance of an alarm by the EAS system 100 is undesirable. Accordingly, the POS terminal 102 includes a marker deactivator. After the purchase transaction is successfully completed, the marker deactivation process is initiated. The marker deactivation process involves: transmitting an RFID deactivation command from the POS terminal 208 (or other RFID-enabled device) to the marker 102; receiving the RFID deactivation command at the marker 102; and performing an operation by the RFID element of the marker to demodulate the AM element of the marker. Once demodulated, the marker is considered to be a deactivated marker. The deactivated marker will still respond to the electromagnetic field emitted from the transmitter circuit 112, 106 (unless a switching version is utilized). However, the frequency of the resonant response signal is outside the range of the EAS system. For example, in some scenarios, the EAS system 100 is tuned to detect a resonant response signal with a frequency between 57KHz and 59KHz, and is configured to issue an alarm in response to such detection. The EAS system 100 will not sound an alarm in response to any response signal having a frequency outside the range of 57 KHz to 59 KHz.The present solution is not limited to the details of this example.

[0041] Illustrative Tokenizer Architecture

[0042] Reference now Figure 3 , provides Figure 1 The illustrated diagram of the architecture of the tagger 102 is shown. The tagger 102 is not limited to Figure 3 Structure shown. Depending on a given application, marker 102 may have any security label, tag, or marker architecture.

[0043] like Figure 3 As shown, the marker 102 includes a housing 126 formed by a first housing portion 204 and a second housing portion 214. The housing 126 may include, but is not limited to, high impact polystyrene. Optionally, an adhesive 216 and a release liner 218 are disposed on a bottom surface of the second housing portion 214 so that the marker 102 can be attached to an item (e.g., an item of merchandise or product packaging).

[0044] A cavity 220 is formed in the first housing portion 204 . The circuit 110 is disposed in the cavity 220 . Figure 4 A more detailed schematic diagram of circuit 110 is provided in FIG. Figure 4As shown, the circuit 110 generally includes an LC circuit 412, 414. The LC circuit generally includes a ferrite rod coil 314 (or other inductive component and / or core material) connected in series with a capacitor 412. The capacitor 412 has a floating first end 416. The second end 418 of the capacitor 412 is connected to a first end 420 of the inductor 414 via the demodulator element 410. The second end 422 of the inductor 414 is floating. During operation, the LC circuits 412, 414 are tuned to produce a resonant signal with a specific amplitude and frequency (e.g., 58KHz) that can be detected by the EAS system 100.

[0045] Circuit 110 also includes an RFID element 406 powered by an energy harvesting element 404. Energy harvesting circuits are well known in the art and therefore will not be described herein. Any known or to-be-known energy harvesting circuit may be used herein without limitation. Such known energy harvesting circuits are described in U.S. patent application Ser. Nos. 15 / 833,183 and 15 / 806,062. In some scenarios, energy harvesting element 404 is configured to collect radio frequency ("RF") energy via antenna 402 and use the collected RF energy to charge an energy storage device (e.g., a capacitor). The stored energy enables operation of RFID element 406. The output voltage of the energy storage device is supplied to RFID element 406 via connection 424.

[0046] RFID element 406 is configured to function as a communication channel with an EAS system (e.g., Figure 1 In this regard, the RFID element 406 stores multiple bits of identification data and emits an identification signal corresponding to the stored multiple bits of identification data. The identification signal is a response to an RFID interrogation signal (e.g., from Figure 1 Antenna bases 112, 116, Figure 2 POS terminal 208, and / or Figure 2 The RFID element 406 is a transponder circuit that is commercially available from Gemplus, ZIAthelia III, Voie Antiope, 13705 La Ciotat Cedex, France. The Model 210 transponder circuit is a passive transponder that operates at 13 MHz and has a relatively large data storage capacity.

[0047] The RFID element 406 is also configured to facilitate deactivation of the marker 102. When the LC circuits 412, 414 are demodulated, the marker is deactivated. Demodulation of the LC circuit is accomplished via a demodulator element 410 connected between a capacitor 412 and an inductor 414 of the LC circuit. The demodulator element 410 is typically configured to alter at least one characteristic of the LC circuit (e.g., capacitance or inductance) such that the resonant frequency of the LC circuit differs from the input frequency by a certain amount (e.g., by more than ±3 KHz from the operating frequency of the EAS system 100, 58 KHz). The LC circuit demodulation is responsive to the RFID element responding to the RFID deactivation signal (e.g., from the RFID deactivation signal). Figure 1 Antenna bases 112, 116, Figure 2 POS terminal 208, and / or Figure 2 The method is performed by receiving an RFID deactivation signal transmitted by the portable read / write unit 212.

[0048] In some scenarios, the demodulator element 410 is designed to switch states when power is supplied to the demodulator element from the RFID element 406, and remain in the new state even when power is removed. The demodulator element 410 includes, but is not limited to, a latch core component or a latch switch component. Latch core components and latch switch components are well known in the art and therefore will not be described in detail herein. Any known or to be known latch core component or latch switch component may be used herein without limitation.

[0049] The latch core component is a magnetic component that is designed to change the magnetic state of the magnetic component from a first magnetic state to a second magnetic state when power is applied to the magnetic component, and to remain in the second magnetic state of the magnetic component when power is removed. The change in magnetic state forces the magnetic field of the latch core to change direction. This change in the direction of the magnetic field of the latch core causes (a) the resonant frequency of the LC circuit to change (e.g., decrease or increase) to a value that falls outside the operating frequency range of the EAS system, or causes (b) the resonant frequency of the LC circuit to return to a value that falls within the operating frequency range of the EAS system. Feature (b) can be a selective feature. For example, if the marker is a disposable marker, the marker will not have the ability to return to its first magnetic state. However, if the marker is a reusable marker, the marker will be provided with the ability to return to its first magnetic state.

[0050] The latch switch component is designed to transition from a closed position to an open position when power is supplied to the latch switch component, and to remain in the open position of the latch switch component when power is removed. In the closed position, a closed circuit is formed between capacitor 412 and inductor 414. In the open position, an open circuit is formed between capacitor 412 and inductor 414. When an open circuit is formed between capacitor 412 and inductor 414, the resonant frequency of the LC circuit changes (e.g., decreases or increases) to a value that falls outside the operating frequency range of the EAS system. In some cases, the marker can be a reusable marker. The reusable marker can be returned to its closed position so that the resonant frequency of the LC circuit once again falls within the operating frequency range of the EAS system.

[0051] Reference now Figure 5 , provides a block diagram of an exemplary architecture of RFID element 406. RFID element 406 may include Figure 5 The components shown are more or less components. However, the components shown are sufficient to disclose an illustrative embodiment of the implementation of the present solution. Some or all of the components of RFID element 406 can be implemented in hardware, software, and / or a combination of hardware and software. Hardware includes, but is not limited to, one or more electronic circuits. Hardware includes, but is not limited to, one or more electronic circuits. Electronic circuits may include, but are not limited to, passive components (e.g., resistors and capacitors) and / or active components (e.g., amplifiers and / or microprocessors). Passive components and / or active components may be adapted to, arranged to, and / or programmed to perform one or more of the methods, processes, or functions described herein.

[0052] RFID element 406 includes a transmitter 506, a control circuit 508, a memory 510, and a receiver 512. It is worth noting that components 506 and 512 are coupled to antenna structure 408 when implemented in tag 102. Thus, antenna structure 408 is Figure 5 406. The antenna structure is tuned to receive signals in an EAS system (e.g., Figure 1 The antenna structure may be tuned to a signal at an operating frequency of the EAS system 100. For example, the operating frequency to which the antenna structure is tuned may be 13 MHz.

[0053] The control circuit 508 controls the overall operation of the RFID element 406. Connected between the antenna structure and the control circuit 508 is a receiver 512. The receiver 512 captures a data signal carried by a carrier signal to which the antenna structure is tuned. In some scenarios, the data signal is generated by on / off keying the carrier signal. The receiver 512 detects and captures the on / off keyed data signal.

[0054] Also connected between the antenna structure and the control circuit 508 is a transmitter 506. The transmitter 506 operates to transmit a data signal via the antenna structure. In some scenarios, the transmitter 506 selectively disconnects or shorts at least one reactive element (e.g., a reflector and / or a delay element) in the antenna structure to provide a perturbation in the RFID interrogation signal, such as a particular complex delay pattern and attenuation characteristic. The perturbation in the interrogation signal can be detected by an RFID reader (e.g., Figure 1 EAS system 100, Figure 2 Portable read / write unit 212, Figure 2 POS terminal 208, and / or Figure 2 programming unit 202) is detected.

[0055] The control circuit 508 can store various information in the memory 510. Accordingly, the memory 510 is connected to the control circuit 508 via the electrical connection 520 and can be accessed by the control circuit. The memory 510 can be a volatile memory and / or a non-volatile memory. For example, the memory 512 can include, but is not limited to, a random access memory ("RAM"), a dynamic RAM ("DRAM"), a read-only memory ("ROM"), and a flash memory. The memory 510 can also include an unsecure memory and / or a secure memory. The memory 510 can be used to store identification data that can be transmitted from the RFID element 406 via an identification signal. The memory 510 can also store other information received by the receiver 512. Other information can include, but is not limited to, information indicating the processing or sale of the commodity.

[0056] Components 506, 508, 512 are connected to an energy harvesting element 404 that accumulates power from a signal induced in antenna 402 due to receiving an RFID signal. Energy harvesting element 404 is configured to supply power to transmitter 506, control circuit 508, and receiver 512. Energy harvesting element 404 may include, but is not limited to, a storage capacitor.

[0057] Illustrative methods for operating the tagger

[0058] Reference now Figure 6 , provides a method for manipulating the markers (e.g. Figure 1 102). The method 600 begins at 602 and continues to 604, in which an energy harvesting element (e.g., Figure 4 The energy harvesting element 404 of the tag performs operations to collect energy (e.g., RF energy and / or AM energy) and uses the collected energy to charge an energy storage device (e.g., a capacitor). At 606, the stored energy is used to enable an RFID element of the tag (e.g., Figure 4At 608, the tag receives a signal from an external device (e.g., Figure 1 Antenna bases 112, 116, Figure 2 POS terminal 208, and / or Figure 2 In response to receiving the RFID deactivation signal, the RFID element of the tag performs an operation to send a signal to the demodulator element (e.g., Figure 4 The RFID element 410 supplies power to the demodulator element. When power is supplied to the demodulator element, the demodulator element switches states. As a result, the resonant frequency of the marker changes (e.g., decreases or increases) to a value that falls outside the operating frequency range of the EAS system. Next, in 614, the RFID element stops supplying power to the demodulator element. Notably, the demodulator element remains in its new state after power is no longer supplied to the demodulator element.

[0059] In some cases, the marker may be a reusable marker. Therefore, it may be desirable to re-tune the marker at a later time. In this case, method 600 continues to optional 616 to 622. 616 to 618 involve: receiving an RFID activation signal by the marker; and performing an operation by the RFID element of the marker to supply power to a demodulator element of the marker. As a result, the demodulator element of the marker switches state so that the LC circuit of the marker (e.g., Figure 4 The LC circuit 412 / 414 of the RFID tag is tuned again. In effect, the resonant frequency of the tag is changed (e.g., decreased or increased) to a value that falls within the operating frequency range of the EAS system. Next, in 622, the RFID element stops supplying power to the demodulator element. Subsequently, 624 is executed, in which the method 600 ends or performs other processing (e.g., returns to 604).

[0060] Although the present solution has been shown and described with respect to one or more embodiments, equivalent changes and modifications will occur to those of ordinary skill in the art after reading and understanding this specification and the accompanying drawings. In addition, although the features of the present solution may have been disclosed with respect to only one of several embodiments, such features may be combined with one or more other features of other embodiments when it is desired and advantageous for any given or specific application. Therefore, the breadth and scope of the present solution should not be limited by any of the embodiments described above. Instead, the scope of the present solution should be defined according to the claims and their equivalents.

Claims

1. A method for operating a security tag, the method comprising: tuning a resonant circuit of the security tag to generate a resonant signal having a first frequency, the resonant signal detectable by an electronic article surveillance system, wherein the resonant circuit comprises an LC circuit having an inductor connected to a capacitor; receiving a deactivation signal via an antenna structure of the security tag, the antenna structure being separate and distinct from the resonant circuit; and in response to the deactivation signal, demodulating the resonant circuit by supplying power from the radio frequency identification element to a demodulator element of the security tag, whereby the demodulator element switches states and causes a resonant frequency of the resonant circuit to change such that the resonant frequency is different from an operating frequency of the electronic article surveillance system, wherein the demodulator element is electrically connected in series between the inductor and the capacitor of the LC circuit, and the RFID element is positioned between the antenna structure and the demodulator element; and wherein the energy harvesting element operates to collect energy and uses the collected energy to charge an energy storage device, uses the stored energy to enable operation of the radio frequency identification element of the security tag, the security tag receives a radio frequency identification deactivation signal transmitted from an external device, and in response to receiving the radio frequency identification deactivation signal, the radio frequency identification element of the security tag operates to supply power to the demodulator element.

2. The method according to claim 1, wherein: The resonant circuit includes an acousto-magnetic circuit including the LC circuit.

3. The method according to claim 1, wherein: Each of the inductor and the capacitor has a floating terminal.

4. The method according to claim 1, wherein: When the demodulator element switches states, the capacitance of the capacitor changes, or when the demodulator element switches states, the inductance of the inductor changes.

5. The method according to claim 1, wherein: The resonant frequency of the resonant circuit is altered to a level that differs by more than ±3 KHz from the operating frequency of the electronic article surveillance system.

6. The method according to claim 1, wherein: The demodulator element includes a latch core component or a latch switch component.

7. The method according to claim 1, wherein: After the power is supplied from the RFID element to the demodulator element, the demodulator element does not have the ability to return to an original state.

8. The method according to claim 1, further comprising: Energy is harvested from wireless signals received from the security tag and used to power the RFID element and to cause selective switching of states by the demodulator element.

9. The method according to claim 1, further comprising: In response to receiving an interrogation signal from the base, an identification is transmitted by the radio frequency identification element.

10. The method according to claim 1, further comprising: The deactivation signal is received from a point of sale terminal.

11. A security label, comprising: a resonant circuit tuned to produce a resonant signal having a first frequency detectable by the electronic article surveillance system, wherein the resonant circuit comprises an LC circuit having an inductor connected to a capacitor; an antenna structure separate from and distinct from the resonant circuit and configured to receive a deactivation signal; a demodulator element electrically connected in series between the inductor and the capacitor of the LC circuit and configured to demodulate the resonant circuit when power is supplied to the demodulator element; and a radio frequency identification element positioned between the antenna structure and the demodulator element and configured to supply the power to the demodulator element in response to the deactivation signal, wherein, during the demodulation, the demodulator element switches states and causes the resonant frequency of the resonant circuit to change such that the resonant frequency is different from an operating frequency of the electronic article surveillance system; Wherein, the security tag further comprises an energy harvesting element, the energy harvesting element performs an operation to harvest energy and use the harvested energy to charge an energy storage device; wherein the stored energy is used to enable operation of the RFID element of the security tag, the security tag receives an RFID deactivation signal transmitted from an external device, and in response to receiving the RFID deactivation signal, the RFID element of the security tag performs an operation to supply power to the demodulator element.

12. The security tag according to claim 11, wherein: The resonant circuit includes an acousto-magnetic circuit including the LC circuit.

13. The security tag of claim 12, wherein: Each of the inductor and the capacitor has a floating terminal.

14. The security tag of claim 11, wherein: When the demodulator element switches states, the capacitance of the capacitor changes, or when the demodulator element switches states, the inductance of the inductor changes.

15. The security tag of claim 11, wherein: The resonant frequency of the resonant circuit is altered to a level that differs by more than ±3 KHz from the operating frequency of the electronic article surveillance system.

16. The security tag of claim 11, wherein: The demodulator element includes a latch core component or a latch switch component.

17. The security tag of claim 11, wherein: After the power is supplied from the RFID element to the demodulator element, the demodulator element does not have the ability to return to an original state.

18. The security tag of claim 11, wherein: The energy harvesting component harvests energy from wireless signals received from the security tag, and wherein the energy is used to power the radio frequency identification component and cause selective switching of states by the demodulator component.

19. The security tag of claim 11, wherein: The RFID element is further configured to, in response to receiving an interrogation signal from the base, issue an identification via the RFID element.

20. The security tag of claim 11, wherein: The antenna structure is further configured to receive the deactivation signal from a point of sale terminal.

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