Abstract:
A method, system and apparatus for managing power use in security systems, which include establishing a detection region, triggering a person detection event, the person detection event based on the detection of a person in the detection region, starting a timer upon triggering the person detection event, and transmitting a tag interrogation signal until the expiration of the timer. The method, system and apparatus can further include determining a relative direction of movement of the person.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    n/a 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    n/a 
       FIELD OF THE INVENTION 
       [0003]    The present invention generally relates to electronic security systems, and in particular, to an improved system and method for power management of electronic article surveillance (“EAS”) systems. 
       BACKGROUND OF THE INVENTION 
       [0004]    Electronic article surveillance (“EAS”) systems are detection systems that allow the identification of a marker or tag within a given detection region. EAS systems have many uses, but most often they are used as security systems for preventing shoplifting in stores or removal of property in office buildings. EAS systems come in many different forms and make use of a number of different technologies. 
         [0005]    A typical EAS system includes an electronic detection unit, tags and/or markers, and a detacher or deactivator. The detection units can, for example, be formed as pedestal units, buried under floors, mounted on walls, or hung from ceilings. The detection units are usually placed in high traffic areas, such as entrances and exits of stores or office buildings. The tags and/or markers have special characteristics and are specifically designed to be affixed to or embedded in merchandise or other objects sought to be protected. When an active tag passes through a tag detection region, the EAS system sounds an alarm, a light is activated and/or some other suitable alert devices are activated to indicate the removal of the tag from the prescribed area. 
         [0006]    Common EAS systems operate with these same general principles using either transceivers, which each transmit and receive, or a separate transmitter and receiver. Typically the transmitter is placed on one side of the detection region and the receiver is placed on the opposite side of the detection region. The transmitter produces a predetermined excitation signal in a tag detection region. In the case of a retail store, this detection region is usually formed at an exit. When an EAS tag enters the detection region, the tag has a characteristic response to the excitation signal, which can be detected. For example, the tag may respond to the signal sent by the transmitter by using a simple semiconductor junction, a tuned circuit composed of an inductor and capacitor, soft magnetic strips or wires, or vibrating magneto acoustic resonators. The receiver subsequently detects this characteristic response. By design, the characteristic response of the tag is distinctive and not likely to be created by natural circumstances. 
         [0007]    An important consideration in connection with the use of such EAS systems is to minimize the power usage of the EAS detection units. Once powered on, current EAS systems operate continuously to create and monitor detection regions or zones. Since the power required to transmit interrogation signals is large compared with the power consumption of other parts of an EAS system, significant power reductions can be realized by deploying a smart EAS system that manages the amount of time that the transmitters operate. 
         [0008]    What is needed is a method and system that can be used to reduce power consumption of EAS systems, particularly by managing transmitter power consumption. 
       SUMMARY OF THE INVENTION 
       [0009]    In accordance with one aspect, the present invention advantageously provides a method for power management in a security system, which method for power management includes establishing a detection region, triggering a person detection event that is based on the detection of a person in the detection region, starting a timer upon triggering the person detection event, and transmitting a tag interrogation signal until the expiration of the timer. The method can further include determining a relative direction of movement of the person. 
         [0010]    In accordance with another aspect, the present invention provides a system for power management in a security system, which system for power management includes a transmitter for producing an applied field in a selected region, a sensor for detecting a person passing through the selected region, and a processor, which operates to trigger a person detection event that is based on the detection of a person in the detection region, to start a timer upon detecting the person detection event, and to transmit a tag interrogation signal until the expiration of the timer. 
         [0011]    In accordance with another aspect, the present invention provides a computer program product that includes a computer usable medium having a computer readable program for power management in a security system, which when executed on a computer causes the computer to perform a method that includes establishing a detection region, triggering a person detection event that is based on the detection of a person in the detection region, starting a timer upon triggering the person detection event, and transmitting a tag interrogation signal until the expiration of the timer. 
         [0012]    Additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The aspects of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    A more complete understanding of the present invention, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein: 
           [0014]      FIG. 1  is a block diagram of an electronic article surveillance system constructed in accordance with the principles of the present invention; 
           [0015]      FIG. 2  is a diagram of an embodiment of an EAS detection unit of the electronic article surveillance system of  FIG. 1 , constructed in accordance with the principles of the present invention; 
           [0016]      FIG. 3  is a diagram of a controller of an EAS detection unit of the electronic article surveillance system of  FIG. 1 , constructed in accordance with the principles of the present invention; 
           [0017]      FIG. 4  is a diagram of an alternate embodiment of a controller of an EAS detection unit of the electronic article surveillance system of  FIG. 1 , constructed in accordance with the principles of the present invention; and 
           [0018]      FIG. 5  is a detailed flowchart of an exemplary power management process in accordance with the principles of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    Referring now to the drawing figures in which like reference designators refer to like elements, there is shown in  FIG. 1  a diagram of an exemplary system constructed in accordance with the principles of the present invention and designated generally as “100”. Electronic article surveillance (“EAS”) system  100  includes EAS detection units  102 ,  104  positioned generally in parallel and at a spaced distance from one another. EAS detection unit  102  can include a transmitter  202  ( FIG. 2 ) and a transmitting antenna  204  ( FIG. 2 ) for producing the electromagnetic fields that are used in conjunction with such systems to detect the presence of a tag, such as tags  106  and  108  affixed to merchandise to be protected. The other EAS detection unit  104  includes a receiver  206  ( FIG. 2 ) and a receiving antenna  208  ( FIG. 2 ), which then operate to detect a disturbance (resulting from the presence of an active tag  106 ) in the electromagnetic fields produced by the EAS detection unit  102 . Detection of an active tag  106 ,  108  can result in the triggering of an appropriate alarm. EAS system  100  can create a detection region  110  in retail space  112 . Detection region  110  can include valid alarm region  114  and over-range or backfield region  116 . A store exit  118  also can be located within detection region  110 . 
         [0020]    Additionally, one of the EAS detection units  102 ,  104 , preferably the EAS detection unit  104  that includes receiver  206  ( FIG. 2 ), provides a sensor system  120  that includes sensors  120 A,  120 B (collectively referred to herein as sensor system  120  as used herein) that is capable of detecting the presence of someone exiting or entering the store between the EAS detection units  102 ,  104  of the EAS system  100 . The sensor system  120  is capable of detecting the relative direction of a person&#39;s movement as that person enters or exits the store. A variety of people detection technologies such as sensors that provide a beam can be used for this purpose, e.g., infrared beam sensors, or other people detection sensors such as photoelectric sensors, body heat sensors, and even floor switches, as desired. These sensors can be deployed at various locations of EAS system  100 . For example, sensor system  120  can be deployed in EAS detection units  102 ,  104 , building posts, door frames and ceilings. Whatever the specific method of implementation, the sensor system  120  is electrically connected to the receiver  206  ( FIG. 2 ) of the EAS system  100  so that the EAS system  100  can be informed when a person  122 , e.g., a shopper, passes between the EAS detection units  102 ,  104  and crosses a people detection line  124  in detection region  110  in an “out” direction or an “in” direction. 
         [0021]    In  FIG. 1 , person  122  is shown located in valid detection region  114  at a point past the people detection line  124  while person  126  is shown located in valid detection region  114  at a point prior to the people detection line  124 . In operation, as discussed in more detail with reference to  FIGS. 3 and 4  below, person  122  causes a people detection event, which in this case is a “people detection out” event because person  122  has crossed detection line  124  in the out direction. On the other hand, person  126  does not generate a people detection event because person  126  has not crossed detection line  124 . However, if person  126  has crossed the detection line  124  in the “in” direction, person  126  causes a people detection event which in this case is a “people detection in” event. This advantageously provides a user of EAS system  100  with the ability to configure system  100  so as to choose which conditions can cause a people detection event, and thereby cause the activation of the EAS transmitter  202 . For example, when the EAS system  100  user, e.g., a retail store operator, does not want the activation of the EAS transmitter when a person  126  crosses people detection line  124  in the “in” direction, the user may define the crossing of detection line  124  in the “in” direction, as a non-detection event. In other words, the crossing of people detection line  124  in the “in” direction is not in a transmission enablement direction. 
         [0022]    In another embodiment, a single EAS detection unit  102  is supplied that uses a transceiver  202  ( FIG. 2 ) and a transceiver antenna  204  ( FIG. 2 ) to establish detection region  110  by producing the electromagnetic fields that are used to detect the presence of tags, such as tags  106  and  108 , affixed to merchandise to be protected. In this embodiment, transceiver  202  and transceiver antenna  204  also function to receive a disturbance in the produced electromagnetic field of EAS detection unit  102 . For example, although  FIG. 2  shows EAS detection unit  102  deployed in a pedestal, the transceiver  202  and/or the transceiver antenna  204  or both can be deployed on a door that is located at a store exit  118 . In this embodiment, transceiver antenna  204  radiates the appropriate electromagnetic or radio frequency field to produce the detection region  110 . 
         [0023]    The processing of data and signals developed by the EAS detection units  102 ,  104  of the EAS system  100 , as well as interaction with the sensor system  120 , is accomplished by a controller  210  associated with the EAS system  100 , that can be generally positioned within the transceivers/receivers  202 ,  206 . In certain embodiments, the controller  210  executes one or more processes associated with EAS applications.  FIG. 3  illustrates an embodiment of controller  210  of EAS detection units  102 ,  104 . In this embodiment, the controller  210  is used to analyze detection data generated by the sensor system  120  and signals received by the receiver  206  to determine the presence of a tag  106  between the EAS detection units  102 ,  104  of the EAS system  100 . The controller  210  executes instructions and manipulates data to perform the operations of EAS system  100  and may be, for example, a central processing unit (“CPU”), an application specific integrated circuit (“ASIC”) or a field-programmable gate array (“FPGA”). The controller  210  also controls the activation or enablement of the transmitters, e.g., transmitter  202 , for all the various configurations of EAS system  100 . 
         [0024]    The controller  210  also controls various registers and counters such as people detection event registers and transmit timers, e.g., “TX_ON_Timer”, each of which relates to the operation of EAS system  100 . These registers and timers can be located in controller  210  or in other memory of EAS system  100  that is in communication with controller  210 . Although  FIG. 2  illustrates a single controller  210  in EAS system  100 , multiple controllers  210  may be used according to particular implementation needs, and reference to controller  210  is meant to include multiple controllers  210  where applicable. In this embodiment, transmitter  202  remains in a deactivated state, until it receives the transmit enable command signal from the controller  210 . 
         [0025]      FIG. 4  illustrates an alternate design of the controller  210  of EAS detection units  102 ,  104  of the EAS system  100 . In this embodiment, an EAS system controller  402  can perform EAS system operations, such as processing the signals received by the receiver  206  to determine the presence of a tag  106  between the EAS detection units  102 ,  104  of the EAS system  100 . However, as illustrated, a separate power controller  404  controls the activation or enablement of the transmitters, e.g., transmitter  202 . In this embodiment, the power controller  404  controls the various registers and counters such as people detection event registers and transmit timers, e.g., “TX_ON_Timer”, each of which relates to the operation of the transmitters  202  of EAS system  100 . In this embodiment, transmitter  202  remains in a deactivated state, until it receives the transmit enable command signal from the power controller  404 . 
         [0026]    Referring again to  FIG. 2 , a motion detector or people sensor  120  is illustrated mounted near the top of a store exit/entrance that is defined by EAS units  102 ,  104  that are integrated into two pillars or support columns. In this embodiment, sensor  120  is an infrared beam sensor, which defines the people detection line  124 . People detection line  124  serves as an event trigger point to notify controller  210  to produce a people detection event when a person crosses the people detection line  124 . The present invention further provides a means to determine the movement of people  122 ,  126  within detection region  110  via sensor system  120 . For example, multiple sensors, e.g.,  120 A and  120 B, of sensor system  120  can create one or more people detection lines or points  124 . As a person or object crosses each detection line, an event signal is generated and processed by the controller  210  to determine the relative direction of the person. 
         [0027]      FIG. 5  is a flow chart illustrating an exemplary method  500  for power management of EAS system  100  using a sensor system  120 . Exemplary method  500  is discussed with reference to EAS system  100 , however, any other suitable system or portion of a system may use appropriate embodiments of method  500  to retrieve and process EAS information to manage the power consumption of EAS detection units  102 ,  104  in EAS detection region  110 . Generally, method  500  describes a person  126  entering a detection region  110  and passing through a people detection line or point  124  to enable a transmitter  202  to transmit communication signals, e.g., interrogation signals, for a predetermined amount of time, such as the duration of a transmitter timer. 
         [0028]    Exemplary method  500  begins at step S 502 , where a determination is made as to whether a people detection event has occurred, such as when a person  122  passes or crosses a people detection line or point  124 . A people detection event can be defined to include all occurrences in which a person passes or crosses a people detection line or point  124 , or it can be limited to include only those cases where the crossing of the people detection line  124  occurs in a certain direction, e.g., the “out” direction. In the illustrative example of  FIG. 1 , persons  122 ,  126  are shown in a valid detection region  114  of detection region  110 . However, person  126  is shown located prior to the people detection line  124 , while person  122  is shown having crossed the people detection line  124  in the “out” direction. In this example, person  122  causes a people detection event to occur which causes a people detection event flag to be set at step S 504 . If no people detection event is detected, then step S 502  is repeated until a people detection event occurs. 
         [0029]    At step S 506 , the people detection event causes a transmitter timer to be reset or cleared and then started. Next, a transmitter timer flag can be set at step S 508 . At step S 510 , a transmitter, e.g., transmitter  202 , is enabled or activated to transmit or radiates the appropriate electromagnetic or radio frequency field to produce the detection region  110 . If the transmitter timer has expired, the transmitter is disabled (step S 514 ), and the process returns to step S 502  to wait for the next people detection event. Otherwise, if the transmitter timer has not expired, the transmitter remains enabled and continues to transmit its appropriate electromagnetic or radio frequency field. 
         [0030]    Transmitter timer is a timer that provides a time period for transmitter operation that can be predetermined and defined by the EAS system user. 
         [0031]    The present invention advantageously provides and defines a comprehensive system and method for managing power consumption in an EAS system using people detection technologies such as infrared beam sensors. 
         [0032]    The present invention can be realized in hardware, software, or a combination of hardware and software. An implementation of the method and system of the present invention can be realized in a centralized fashion in one computing system or in a distributed fashion where different elements are spread across several interconnected computing systems. Any kind of computing system, or other apparatus adapted for carrying out the methods described herein, is suited to perform the functions described herein. 
         [0033]    A typical combination of hardware and software could be a specialized or general-purpose computer system having one or more processing elements and a computer program stored on a storage medium that, when loaded and executed, controls the computer system such that it carries out the methods described herein. The present invention can also be embedded in a computer program product, which comprises all the features enabling the implementation of the methods described herein, and which, when loaded in a computing system is able to carry out these methods. Storage medium refers to any volatile or non-volatile storage device. 
         [0034]    Computer program or application in the present context means any expression, in any language, code or notation, of a set of instructions intended to cause a system having an information processing capability to perform a particular function either directly or after either or both of the following a) conversion to another language, code or notation; b) reproduction in a different material form. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. Significantly, this invention can be embodied in other specific forms without departing from the spirit or essential attributes thereof, and accordingly, reference should be had to the following claims, rather than to the foregoing specification, as indicating the scope of the invention. 
         [0035]    It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described herein above. A variety of modifications and variations are possible in light of the above teachings without departing from the spirit or essential attributes thereof, and accordingly, reference should be had to the following claims, rather than to the foregoing specification, as indicating the scope of the of the invention.