JP2009543184A - Wireless synchronized operation of pulsed EAS system - Google Patents

Abstract

Systems and methods are provided for providing wireless synchronized operation of multiple electronic article surveillance (EAS) systems. The method includes wireless communication between each of a plurality of controllers connected to a plurality of detectors of a plurality of EAS systems and wireless communication from at least some of the other controllers by each communication receiver of the controller. And receiving. The communication receiver may be separate from the tag detection receiver.
[Selection] Figure 3

Description

  The present invention relates generally to electronic article surveillance (EAS) systems, and more particularly to systems and methods for providing synchronized operation in EAS systems.

2. Description of Related Art Acoustomagnetic or magnetomechanical electronic article monitoring, or “EAS” detection systems, excite EAS tags by transmitting electromagnetic bursts at the tag's resonant frequency. If the tag is present in the electromagnetic field formed by the transmission burst, the tag begins to resonate at an acousto-magnetic or magneto-mechanical response frequency that is detectable by the receiver of the detection system. The detection unit then provides some kind of signal, for example an alarm signal indicating the detection of a response from the EAS tag.

  In an EAS system, the transmit burst signal generally does not end abruptly, but instead drops exponentially due to transmitter circuit resonance. If the transmissions from neighboring units are not synchronized in time, the unit will transmit and receive at the same frequency, so false detection can occur. These false detections lead to false alarms.

  It is known to use multiple detection units, such as multiple detection columns that monitor a large area, such as a retail store exit. Each of these detection columns typically includes multiple antennas that are controlled from a single multi-channel controller. The controller adjusts and synchronizes the antenna operation of each of the detection columns.

  It is also known to use a separate controller for each of the detection units. In this configuration, communication between the controllers is provided to coordinate the operation of each unit, including antenna operation synchronization. These multiple controller systems are known to use wired synchronization in which communication signals are sent between a plurality of controllers via one or more wired connections. Wired installation and connection between multiple detection units can be complex and time consuming. For example, if it is necessary to dig into an existing floor to install the wiring, this procedure adds time and expense to the installation. Moreover, installation problems tend to increase due to, for example, installation complexity or the use of specialized equipment.

  It is also known to provide wireless synchronization to communicate with other controllers associated with other detection units. In these systems, synchronous communications are sent outside the standard transmission window. In particular, the synchronization signal is transmitted during a reception window that adversely affects the received signal over a long distance. In addition, a high sensitivity receiver is used to detect the synchronization signal. This high sensitivity may cause controllers at different locations (eg, different exits) to detect synchronization signals intended for controllers at other locations. Thus, isolation involves the problem of causing miscommunication and control problems.

SUMMARY OF THE INVENTION In one embodiment, a method for information communication between a plurality of detectors in a plurality of electronic article surveillance (EAS) systems is provided. The method includes: wireless communication between each of a plurality of controllers connected to a plurality of detectors of a plurality of EAS systems; and wireless communication from at least some of the plurality of controllers. Reception by the machine may also be included. The communication receiver may be remote from the tag detection receiver.

  In another embodiment, a method is provided for controlling transmissions between multiple electronic article surveillance (EAS) systems. This method involves transmitting an excitation signal to the interrogation zone during the transmission phase, receiving a signal from the excitation tag in the interrogation zone during this transmission phase, and determining the noise average during the noise averaging phase where no transmission occurs. Including. The method may further include processing of the received signal during a detection processing phase in which no transmission or reception occurs, and wireless information communication between multiple detectors of multiple EAS systems during the communication phase.

  In yet another embodiment, a system having a plurality of electronic article surveillance (EAS) systems is provided. The system includes a plurality of detectors and a plurality of controllers, each of which is detected by at least one of the plurality of detectors and defines a plurality of EAS systems. The controller may have a communication receiver. The controller may have a communication receiver. The system may include a communication antenna connected to the communication receiver and configured to receive wireless communication from other controllers.

For a better understanding of the various embodiments of the present invention, reference should be made to the following detailed description that should be read in conjunction with the accompanying drawings, in which like numerals indicate like parts, in which: I want.
FIG. 1 is a block diagram of an electronic article surveillance (EAS) system associated with various embodiments of the invention that may be implemented. FIG. 2 is a diagram of a detector array of the EAS system of FIG. 1 having a controller configured in accordance with an embodiment of the present invention. FIG. 3 is a block diagram illustrating a controller configured according to an embodiment of the present invention. FIG. 4 is a timing diagram illustrating a multi-stage processing cycle according to an embodiment of the present invention. FIG. 5 is a diagram of a phase modulation scheme for coding message information according to an embodiment of the present invention. FIG. 6 is a flowchart of a method for controlling transmission of multiple detectors of an EAS system according to an embodiment of the present invention. FIG. 7 is a block diagram of multiple detectors illustrating frequency division multiplexing and frequency reuse according to an embodiment of the present invention.

Detailed Description of the Invention

  Various embodiments of the present invention provide for synchronized operations, and more particularly synchronized operations, such as several electronic article surveillance (EAS) systems, each EAS system generally having one controller and at least one coil. Methods and systems for communication and / or transmission between are provided. A representative EAS system will be described first, followed by various embodiments of the present invention for controlling and configuring the EAS system, particularly for synchronous operation of the EAS system.

  An embodiment of a system having one or more EAS systems 20 is shown in FIG. The EAS system 20 may include a plurality of detector units 22. As is known for detecting EAS tags 26 having a predetermined characteristic (eg, resonant frequency), each of the detector units 22 monitors a region 24 (eg, within a specific range of the detector unit 22). You may comprise. The range for each region 24 may overlap with the adjacent region 24. Further, the detector unit 22 may be configured to convey information between them using a suitable communication link. In one embodiment, communication between detector units 22 is provided through a wireless communication link 28. Note that any one of the detector units 22 can communicate with some or all of the other detector units 22.

  The detector unit 22 is in any form that is desirable or necessary, such as a Sensormatic ™ detector unit available from Tyco Fire & Security (Boca Rato, Florida). As an example, FIG. 2 is an illustration of the detector unit 22 of the EAS system 20 that may be controlled and synchronized according to various embodiments of the present invention as described herein. Specifically, each detector unit 22 may include a detector portion 30 that defines the detection region 32 to detect the EAS tag 34 within the detection region 32 (eg, between different detector portions). . Each detector portion 30 of the detector unit 22 in one embodiment may include a plurality of antenna columns (eg, one antenna column 36 and one antenna column 38). Each of the antenna columns 36 and 38 may be connected to a controller 40 to control transmission from these antenna columns 36 and 38. Each controller 40 is configured to communicate with the controller 40 of the other antenna column. In other embodiments, a single controller 40 may be connected to multiple antenna posts 36 or 38 to define the EAS system 20 (shown in FIG. 1).

  In particular, the controller 40 controls (e.g., the transmission of the excitation signal to the EAS tag 34 and the reception of the signal generated by the EAS tag 34) (e.g., synchronization) from the antenna columns 36 and 38, respectively. Can be configured. In operation, for example, upon receipt of a signal from an EAS tag 34 that is within the detection region 32 and has not yet been deactivated by a deactivator unit (not shown), a visual and / or audible alarm is immediately received. Can be given.

  When referring to the EAS system 20 herein, it should be noted that this generally refers to a system having one controller 40 and at least one coil, for example in the antenna post 36 or 38. However, various embodiments will be implemented in connection with EAS system 20 having different configurations. For example, various embodiments provide transmission or communication between EAS systems 20 having a single controller 40 each connected to a plurality of antenna posts 36 or 38. The controller 40 could also be integrated into a power pack or a single electronics unit.

  Furthermore, the detector unit 22 is typical of many detector systems and is provided only as an example. For example, the controller 40 may be placed in each antenna column or adjacent to the antenna column. Additional antennas that only receive signals from a particular EAS tag 34 may be provided.

  A block diagram of a representative controller and what is integrated within this controller 40 is shown in FIG. The controller 40 may generally include a power amplifier / transmitter unit 42 and a tag detection receiver, such as a detection analog front end unit 44, which unit 44 is a single antenna (in one embodiment, an interrogation antenna 46). An EAS tag supervisory control part that controls transmission / reception of signals in (a) may be defined together. The power amplifier / transmitter unit 42 and the detection analog front end unit 44 control transmission and reception at the interrogation antenna 46 for monitoring the EAS tag in the EAS system 20 (shown in FIG. 1) in any known manner. May be provided. Note that the interrogation antenna 46 may be provided as part of the antenna posts 36 and 38 (shown in FIG. 2).

  The controller 40 may include a wireless communication receiver, such as a communication analog front end unit 47, which may be used, for example, between different controllers 40 (eg, in more detail below) in one or more EAS systems 20 (shown in FIG. 1). It is connected to a given communication antenna 48 for communication between controllers 40 connected to different antenna columns as will be described. In one embodiment, the communication antenna 48 may include a small single loop antenna configured to receive communications from other controllers 40, which includes a plurality of detector units 22 (shown in FIG. 1). And / or used to synchronize multiple EAS systems 20. The communication analog front end unit 47 performs low gain operation (eg, gain for communication in the range of about 25 feet to about 35 feet) and bandpass filtering based on the desired or required controller 40 communication frequency. You may comprise so that it may give. The gain of the communication analog front end unit 47 is configured such that the communication antenna 48 is sensitive only to the near field. For example, the communication analog front end unit 47 may be located within a portion of the EAS system 20, such as in a predetermined area (eg, between antenna pole controllers at the outlet of a retail store), between the controllers 40 between adjacent EAS systems 20. Can only be configured to give communication. It should be noted that transmission from one controller 40 to another controller 40 is provided using the interrogation antenna 46 with a transmission signal received using a separate communication antenna 48.

  The controller 40 may include a processor 50 connected to each of the power amplifier / transmitter 42, the detection analog front end 44 and the communication analog front end unit 47. The processor 50 could be configured to control communication between the controllers 40. In particular, as shown in the timing diagram of FIG. 4, the controller 40 is configured to provide multi-stage communication and / or processing cycles (eg, four-stage communication / processing cycle 60), which communicates between different controllers 40. Make it possible. Note that the duration of each phase and / or the length or duration of each transmission window may be different. More specifically, the first stage 62 is a high power transmission stage where an unregulated signal is transmitted to the interrogation area, eg, transmitted to the detection area 32 (shown in FIG. 2) during the transmission period 63. Is done. For example, a signal composed of a frequency or a frequency range that excites any EAS tag in the interrogation area is transmitted. This transmission may include transmission of electromagnetic bursts at the resonant frequency of the EAS tag detected using a power amplifier / transmitter 42 and an interrogation antenna 46 (both shown in FIG. 3), as is known. In this first stage 62, a signal from an excited EAS tag may also be received.

  The second stage 64 is a noise averaging stage where no transmission occurs. This stage is used to provide a noise level for comparison of any received signal (eg, from an excited EAS tag). The third stage 66 is a detection process stage in which no transmission or reception occurs. This third stage 66 is used for the detection process (which may be performed by the processor 50 (shown in FIG. 3)) and the result is transferred from the controller 40 to another controller 40 (eg, a different EAS system). Determine the message to be transmitted (in relation to other antenna columns at the outlet of the retail store that will be present in 20). Since the result of the third step 66 may not be the detection of the EAS tag, an appropriate alarm (for example, an audible or visual alarm) is generated in that case.

  The fourth stage 68 is a communication stage where a low power conditioned signal (e.g., a communication burst) to be adjusted is transferred from the controller 40 to another controller 40, e.g., adjacent or neighboring during the transmission window 69. It is transmitted to the controller 40. This adjacent or neighboring controller 40 may be in a different EAS system 20. The low power adjustment signal may be transmitted using the interrogation antenna 46 (shown in FIG. 3). While transmitting the communication signal, the controller 40 simultaneously monitors a dedicated low-sensitivity reception channel for communication signals from other controllers 40. The communication analog front end unit 47 (shown in FIG. 3) may be configured to provide a receive channel. After the communication signal is transmitted and received by the other controller 40, the processor 50 (shown in FIG. 3) processes the received signal. For example, the communication signal typically defines a message signal, and the processor 50 demodulates the message signal from the other controller 40 to determine further operations to be performed. For example, based on the local state and the state of one or more adjacent controllers 40 determined by the communication signal, the controller 40 determines the next operation to be performed in the next first stage 62 which is the next transmission stage. can do. Note that different communication stages and timings are provided as desired or required, eg, depending on the type of EAS system or detector.

  Different messages may be communicated between the controllers 40 via communication signals during the communication phase 68 using the phase modulation scheme 70 as shown in FIG. The phase modulation plan 70 is changed or modified based on, for example, the type of EAS system or the type of detector. The phase modulation scheme 70 may be used in connection with an EAS detector from, for example, Tyco Fire & Security (Boca Raton, Florida). In particular, if N bits are transmitted for each communication burst, a 1.6 millisecond (msec) communication burst is used because the first partition habituates the receiver (eg, the communication analog front end unit 47 in the signal stage). Are divided into N + 1 sections 72 configured as shown in FIG. Subsequent section 72 is an inverted phase indicating "1" bit or a non-inverted phase indicating "0" bit. Using phase modulation and / or amplitude and frequency modulation, another signal is provided that communicates different information. For example, a phase modulation scheme can be used where up to 8 bits are transmitted per burst. Using a phase modulation scheme 70 or other modulation scheme, different messages are communicated between the controllers 40 (shown in FIG. 3), including for example:

1. The “Tx Off Check” message requests adjacent detectors to prevent interrogation bursts in the next transmission phase.

2. The “verification” message indicates that the transmission sequence should be kept in the same state as the previous transmission stage while verifying the tag signal. This message can be used to determine if adjacent detectors should be turned off because the detector excites the tag in different interrogation areas by repeating the signal at the same frequency and antenna stage. Good.

3. The “area detection” message determines which antenna “finds” the EAS tag signal more strongly.

4. The “synchronization” message determines the transmission timing in the transmission phase for use in synchronous transmission.

  Note that other messages may be provided to control operation, eg, control transmissions from multiple detectors 22 (shown in FIG. 1). Note also that other modulation schemes may be provided to convey message information.

  A method 80 for controlling the operation of multiple EAS systems, eg, transmission of multiple detectors of an EAS system, is shown in FIG. Specifically, at 82, communication messages are communicated (eg, sent and received) between the controller and one or more associated EAS system detectors. This may include transmission of low power adjustment message signals (allowing higher data rate communication) via transmission bursts in the transmission window of the communication phase (shown in FIG. 4). The message signal (which is a near-field full duplex signal) is communicated to a local controller (eg, a controller in a predetermined or predefined area of one or more EAS systems). During this communication phase, the controller also receives message signals from other controllers, for example on a dedicated low sensitivity receiving channel, as described in more detail above.

  The message signal is then processed at 84, which may include demodulation of the signal. In one embodiment, the phase of the signal during the time period (shown in FIG. 5) is compared to determine, for example, whether the phase is reversed or the phase reversal pattern is confirmed. The control information or message (described above) may be encoded into a phase change, which is determined during this processing phase. In addition, the current state of the detector may be determined. Based on the processed received message signal and / or detector status, a determination is made at 86 as to whether manipulation is required. For example, if no operation is required, for example, if the detector is in a hold state, then method 80 returns to sending and receiving messages at 82, which includes sending a message that includes the current state of the detector. obtain. If manipulation is required, for example, if a message is received indicating that the next transmission signal is disturbed, then at 88 the detector is controlled accordingly (eg, preventing the next transmission burst). . Thereafter, method 80 returns to sending and receiving messages at 82, which may include sending a message that includes the current state of the detector or a recent operation (eg, blocking transmission bursts).

  When multiple detectors 22 are applied to an area or location that defines one or more EAS systems 20 (e.g., outlets of retail stores), frequency division multiplexing may cause the controller signal as shown in FIG. Note that it can be used to detach. Furthermore, frequency reuse may also be provided to the entire controller at different locations (eg, different exits) of the EAS system. A plurality of antenna posts 90 and 92 may be provided at each of a first location 94 (eg, a first exit) and a second location 96 (eg, a second exit). For example, the multiple EAS pillars of Tyco Fire & Security (Boca Raton, Florida) are provided with five different available frequency channels (eg, 48 kHz, 53 kHz, 58 kHz, 63 kHz and 68 kHz). Each antenna column 90 and 92 at each of the first and second locations 94 and 96 is transmitted on a different available frequency using frequency reuse at each of the first and second locations 94 and 96. Can be configured.

  Accordingly, various embodiments of the present invention are provided to control, and more particularly to synchronize the operation of detection units in multiple EAS systems. For example, a synchronization operation can be used to determine whether an EAS tag is detected between two detectors, or whether a signal from one detector is interfering with another detector. It may be used. The individual communication antenna is configured and provided to have a dedicated low-sensitivity reception channel. A low power regulated communication transmitter that provides higher data rate communication is thereby provided between the controllers connected to each of the plurality of detectors of the EAS system. Message communication is performed during the communication burst window of the communication phase. Near field sensitivity and frequency division multiplexing allow full duplex communication.

  Various embodiments or components, such as controller 40 or other components, may be implemented as part of a computer system, or may be separate or integrated into an EAS system. The computer system will include a computer, input devices, a display unit and an interface (eg, for accessing the Internet). The computer will include a microprocessor. The microprocessor can be connected to a communication bus. The computer can also include a memory. The memory may include random access memory (RAM) and read only memory (ROM). The computer system may further include a storage device, which may be a hard disk drive or a removable storage device (eg, floppy disk drive, optical disk drive, etc.). The storage device may be other similar means for loading computer programs or other instructions into the computer system.

  The term “computer” as used herein is a processor-based or microprocessor-based system that includes microcontrollers, reduced instruction set circuits (RISC), application specific integrated circuits (ASICs), logic Circuits, digital signal processors, and systems using any other circuit or processor capable of performing the functions described herein. The above examples are not intended to limit the definition and / or meaning of the term “computer” in any way.

  The computer system executes a set of instructions stored in one or more storage elements to process input data. The storage element may store data or other information that is desired or required. This storage element may be in the form of an information source in a processing device or a physical memory element.

  This set of instructions may include various instructions that instruct the computer as a processing device to perform special operations, such as the methods and processes of the various embodiments of the invention. The set of instructions may be in the form of a software program. The software may be in various forms such as system software or application software. Further, the software may be a form of collecting separate programs, a program module in a larger program, or a part of the program module. The software may also include modular programming in the form of object oriented programming. The processing of the input data by the processing device may be performed according to the user command, the result of the preceding processing, or the result made in response to a request made by another processing device.

  As used herein, the terms “software” and “firmware” are interchangeable and include any computer program stored in memory for execution by a computer, including RAM memory, ROM memory, EPRO memory , EEPROM memory, and non-volatile RAM (NVRAM) memory. The above memory types are exemplary only, and thus do not limit the types of memory that can be used for storing computer programs.

It should be appreciated that variations and modifications of the various embodiments of the present invention can be made without departing from the spirit thereof. The objectives of the various embodiments are not to be construed as limiting the particular embodiments disclosed herein, but are construed only in accordance with the appended claims when considering the above disclosure. Please understand that it will be done.

Claims (20)

A method for communicating information between a plurality of detectors of a plurality of electronic article surveillance (EAS) systems, comprising:
Wirelessly communicating between each of the controllers of the plurality of EAS systems is wirelessly communicating between each of the plurality of controllers connected to the plurality of detectors of the plurality of detectors of the plurality of EAS systems;
A method in which wireless communication from at least a portion of a plurality of other controllers is received at each communication receiver of the controller, the communication receiver being remote from the tag detection receiver. The method of claim 1, wherein an antenna connected to the communication receiver is configured to receive the wireless communication, the antenna being remote from the interrogation antenna. 3. The method of claim 2, wherein the antenna comprises a single loop antenna. The method of claim 1, wherein during a communication step away from a tag activation transmission step, a message signal from one of the plurality of controllers is wirelessly transmitted to at least one of the other plurality of controllers. Further comprising a method. The method of claim 1, further comprising phase modulating the communication in which the wireless transmission defines a message. The method of claim 1, wherein the wireless transmission modulates the communication at least one of amplitude and frequency to define a message. The method of claim 1, further comprising configuring the communication receiver to provide near field sensitivity. The method of claim 1, further comprising wirelessly transmitting using an interrogation antenna remote from a communication antenna connected to the communication receiver. The method of claim 1, wherein the communication stage for communicating between the plurality of controllers occurs away from the transmission stage, the noise averaging stage and the detection processing stage. The method of claim 1, further comprising frequency division multiplexing communications between a plurality of controllers. 2. The method of claim 1, wherein each of the plurality of controllers is connected to a different one of the plurality of detectors. The method of claim 1, wherein the plurality of detectors are configured as column units. The method of claim 1, wherein the wireless communication comprises information related to transmission control. A method of controlling transmission between a plurality of electronic article surveillance (EAS) systems, comprising:
Send an excitation signal to the interrogation zone during the transmission phase,
Receiving a signal from an excited EAS tag in the interrogation zone during the transmission phase;
Determine the noise average during the noise averaging stage where no transmission occurs,
Process the received signal during the detection process phase where no transmission or reception occurs,
A method of wirelessly communicating information between a plurality of detectors of a plurality of EAS systems during a communication phase. 15. The method of claim 14, wherein the wireless communication of information comprises one of phase, amplitude, and frequency modulation. 15. The method of claim 14, wherein wireless communication of information includes the use of an interrogation antenna that transmits information, the interrogation antenna also being used to transmit the excitation signal and receiving the wirelessly transmitted information. A method using a communication antenna for the purpose. A system having a plurality of electronic article surveillance (EAS) systems,
Multiple detectors;
A plurality of controllers, each connected to at least one of the plurality of detectors, defining the plurality of EAS systems, and having a communication receiver;
A communication antenna connected to the communication receiver and configured to receive wireless communication signals from a plurality of other controllers. 18. The system of claim 17, wherein the controller is configured to control wireless communication to transmit a wireless communication signal during a communication phase that is different from a transmission phase in which a tag excitation signal is transmitted. 19. The system of claim 18, wherein the transmission of the wireless communication signal and the transmission of the tag excitation signal are provided by an interrogation antenna that is separate from the communication antenna. 18. The system of claim 17, wherein the controller is configured in one stage for amplitude and frequency modulation of the wireless communication signal.

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