Abstract:
A system and method described for tracking portable devices. The system may include a transmitter which transmits wireless inquiries to a plurality of portable devices and a receiver receiving replies to the inquiries from the portable devices. In addition, the system may include a memory storing identifier data corresponding to the portable devices and a processor coupled to the memory and to the receiver, the processor retrieving from each reply, identifier data uniquely identifying a particular one of the portable devices which generated the reply and comparing the identifier data to the stored identifier data. Furthermore, the system may include an alarm system coupled to the processor and controlled based on the comparison of stored identifier data to the identifier data retrieved from the replies.

Description:
BACKGROUND INFORMATION 
   Conventional portable computing devices are becoming more powerful and expensive. The problem with such portable devices is that, due to their small size and/or light weight, they are often misplaced or stolen. For example, warehouse employees often utilize portable bar code scanners which, due to their small size, are difficult to manually track. Thus, replacement costs for these devices can become burdensome. 
   Some conventional security systems have attempted to deal with this issue. For example, small metal tags have been affixed to such portable devices so that, each time such a portable device is carried through a security area, the metal tag activates an alert system which notifies security personnel. However, such security systems cannot determine whether this portable device is being legitimately carried through the security area or whether it is being stolen. Thus, security personnel must conduct time-consuming investigations to make these determinations. 
   SUMMARY OF THE INVENTION 
   A system and method described for tracking portable devices. The system may include a transmitter which transmits wireless inquiries to a plurality of portable devices and a receiver receiving replies to the inquiries from the portable devices. In addition, the system may include a memory storing identifier data corresponding to the portable devices and a processor coupled to the memory and to the receiver, the processor retrieving from each reply, identifier data uniquely identifying a particular one of the portable devices which generated the reply and comparing the identifier data to the stored identifier data. Furthermore, the system may include an alarm system coupled to the processor and controlled based on the comparison of stored identifier data to the identifier data retrieved from the replies. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
       FIG. 1  shows an exemplary embodiment of a system according to the present invention; and 
       FIG. 2  shows an exemplary embodiment of a method according to the present invention. 
   

   DETAILED DESCRIPTION 
   The present invention relates to a cordless/wireless identification security system and method. The exemplary embodiment of the present invention described below utilizes, as an example of cordless technology, Bluetooth technology. Bluetooth technology is designed to enable fast, robust and secure wireless communication between small, portable computing devices. Thus, this technology eliminates the need for proprietary cables which had previously been required to enable device connectivity. Those skilled in the art will understand that other cordless/wireless technologies may be utilized with the present invention. 
     FIG. 1  illustrates an exemplary embodiment of the system according to the present invention. In particular,  FIG. 1  shows a facility  1  which utilizes portable devices  16 . The portable devices  16  may be laptop computers, bar code scanners, computer terminals, beepers, phones, printers, personal digital assistants, etc. Each of various employees of the facility  1  receives a device  16  at a beginning of a working shift and returns the device  16  at the end of the shift. To assure that the devices  16  are not misplaced or stolen, the facility  1  utilizes a cordless identification security system and method for tracking the devices  16 . 
   This system may include a security monitor device  12  and a control computer  24 . The security monitor device  12  may be situated, for example, in a security area  10  of the facility  1 . The security area  10  also may include a security office  18  where an alert system  14  and security personnel may be located. 
   The control computer  24  may be situated, for example, in a control room  20  of the facility  1 . The control computer  24  may collect and maintain a record for each of the devices  16 . In particular, the record may include technical information about a type of each device  16 , a unique identification number (“UIN”) for each device  16  which is assigned by the manufacturer, status and location information for each device  16  (e.g., whether the device  16  is activated and an indication as to where the device  16  may be situated), etc. The control computer  24  updates the record of each device  16  each time there is a change to the status of the device  16 . Each time the facility  1  receives a new device  16 , a corresponding record is generated and stored by the control computer  24 . 
   Each of the portable devices  16  and the security monitor device  12  may include, for example, a Bluetooth radio transceiver, as is known in the art, which allows wireless communications to be established and facilitates data exchange. This radio transceiver may operate within, e.g., the 2.4 GHZ ISM band utilizing a 2.4 GHz Short Range Radio link protocol as defined by the Bluetooth Special Interest Group (SIG) in Bluetooth System Specification v. 1.1 (Dec. 1, 2000). 
   Bluetooth-enabled devices may be grouped into a plurality of piconets with each piconet including up to seven “slave” devices and one master device. The master device&#39;s clock and hopping sequences may be synchronized with those of the corresponding slave devices. In the exemplary embodiment of  FIG. 1 , a master device  12 ′ (which is similar to the security monitor device  12 ) and two “slave” devices  16 ′ (which are similar to the device  16 ) are shown in Piconet A. As described above, the master device  12 ′ of Piconet A may have up to seven “slave” devices  16 ′. Additionally, each of Piconets B–G must have a master device  12 ′ and may have up to seven “slave” devices  16 ′. 
   As would be understood by those skilled in the art, each of the Bluetooth-enabled devices may operate in a plurality of modes. By default, the device may be placed in a standby mode, during which the device performs scanning operations. The standby mode may allow the device to (a) listen for its own device access code for the duration of a scan window (e.g., 11.25 ms) (i.e., a request to enter a “page scan mode”) or (b) listen for an inquiry access code (i.e., a request to enter a “inquiry scan mode”). The page scan mode is utilized to set up an actual connection between the two or more Bluetooth-enabled devices. The inquiry mode, on the other hand, is used to determine which devices are within the scan range of the another Bluetooth-enabled device. 
     FIG. 2  shows an exemplary embodiment of the method according to the present invention. The method is performed continuously as long as the identification security system is active. In step  100 , security monitor device  12  is in the inquiry mode, transmitting inquiries to all devices  16  within the security area  10 . The transmission of the inquires may be performed continuously. Each inquiry includes an inquiry access code and a request to all Bluetooth-enabled devices to respond and identify themselves. The devices  16  which are situated within the security area  10  “listen” for the inquiry access code and generate replies thereto which are forwarded to the security monitor device  12  (step  104 ). Each reply includes the UIN of the corresponding device  16 . If no reply is received, the security monitor device  12  continues transmitting inquiries (step  100 ). 
   Once the security monitor device  12  has received a reply, the UIN of the device  16  is extracted and forwarded to the control computer  24  along with the date and time when the reply was received by the security monitor device  12  (step  106 ). The control computer  24  compares this UIN to a database of registered UINs to find a match (step  108 ). If no match is found, the control computer  24  indicates that the device  16  is not registered at the facility  1  (step  110 ). Thus, the control computer  24  does not need to activate the alert system  14  and the employee with the device  16  may exit the facility  1 . 
   Alternatively, the system and method may be utilized to detect the existence of unregistered devices  16  in areas where they are not supposed to be. In this case, when the control computer  24  finds no match in step  110 , the control computer  24  may activate the alert system  14  and inform the security personnel of the unregistered device  16  present in the security area  10 . 
   If there is a match in step  108 , the control computer  24  activates the alert system  14  (step  112 ). The activation of the alert system  14  may be made in many different ways. For instance, the alert system  14  may notify security personnel in the security office  18  who may then prevent the employee with the device  16  from exiting the security area  10 . The alert system  14  may also activate security equipment (e.g., video cameras) situated, for example, in the security area  10  to record activities therein for as long as the device  16  is present within the security area  10  and continues to reply the inquires of the security monitor device  12 . The alert system  14  may also automatically lock the security area  10  so that no one can leave the security area  10  until the device  16  is located. All of the above mentioned activities may be transmitted to the control computer  24  which may record the activities in a corresponding record for the particular device  16 . 
   In another exemplary embodiment of the present invention, the system and method may be utilized to track misplaced devices  16 . For instance, every time an employee carrying the device  16  passes through a particular security monitor device  12 , this information is recorded by the control computer  24  so that later the movements of the device  16  may be tracked. The system and method according to the present invention may also be utilized to locate a device  16  or a employee carrying device  16  within the facility  1 . The facility  1  may have a large number of the security monitor devices  12  which effectively cover the area of the facility  1 . So that, when the device  16  is carried around the facility, its location is known. 
   In an alternative exemplary embodiment of the present invention, the system and method may be used to track employees time. For example, every employee may be assigned a Unique Employee Identification Number (“UEIN”). This UEIN may be stored in the control computer  24  along with the UIN of an assigned device  16  which the employee may carry as he enters/exits the facility  1  through the security area  10 . For example, when an employee enters the facility  1  through the security area  10 , the security monitor device  12  receives a reply to its inquiries from the device  16 . The security monitor device  12  forwards this reply to the control computer  24  which determines the corresponding UEIN as a function of the UIN and records the date and time when the employee entered the facility  1 . Based on that information, the facility  1  may track the employee&#39;s time. 
   The system and method may also be utilized in retail environments. For example, in a retail environment, Bluetooth-enabled devices may be integrated with Radio Frequency Identification tags (“RFID”). These integrated devices may serve as part of a dual-mode security system which allows detection of both the RFID tags and the Bluetooth-enabled devices. Thus, facilities may keep track of inventory of these devices  16  and prevent the devices  16  from leaving the facility  1 . This reduces operating costs due to misplaced or stolen devices  16 . 
   There are many modifications to the present invention which will be apparent to those skilled in the art without departing form the teaching of the present invention. The embodiments disclosed herein are for illustrative purposes only and are not intended to describe the bounds of the present invention which is to be limited only by the scope of the claims appended hereto.