Abstract:
A system and method is provided to track positions of a portable electronic device. Different communication modules capable of retrieving position signals are enabled selectively according to the status/type of position signals of the portable electronic device. All of the different communication modules are enabled when the portable electronic device locates around a boundary between different regions that require different communication modules to obtain geography information. Therefore, by means of seamless transferring operation between different communication modules, a remote manager may be able to continuously monitor the positions of the portable electronic device.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of Invention 
         [0002]    The present invention relates to a system and method for tracking positions of a portable electronic device, and more particularly, to a seamless, trackable portable electronic device, and a system and method for seamlessly tracking positions of the portable electronic device. 
         [0003]    2. Related Art 
         [0004]    The global positioning system (GPS) is a very popular position tracking system with the help of satellites. However, when the satellites and the receiver are separated by buildings, the positioning signals cannot be received by the receiver due to the obstacles. In other words, once the user goes indoors, the GPS cannot function properly. 
         [0005]    To solve this problem, the prior art provides a positioning device that combines the GPS and a short-distance wireless communication protocol. It enables the user to select an appropriate position tracking method according to his position. For example, when the user is outdoors, the GPS is used for outdoor positioning information. When the user is indoors, an ultra wide band wireless communication positioning module is used to provide indoor positioning information. 
         [0006]    In the field of remote monitoring and tracking, the above-mentioned technique cannot provide the indoor and outdoor positioning information to a remote monitor without any interruption. This is because the conventional positioning device provides real-time positioning information to the user, i.e., the holder of the positioning system. However, the user has to switch between different modes for receiving the positioning information. Therefore, during the remote monitoring and tracking, the position information of the user cannot be continuously provided to the remote monitor if the user does not immediately switch from the GPS to the ultra wide band wireless communication positioning module as he goes from outdoors to indoors. 
       SUMMARY OF THE INVENTION 
       [0007]    To resolve the aforesaid technical problems of the prior art, the present invention provides a seamless, trackable portable electronic device, and a system and method for seamlessly tracking positions of the portable electronic device. 
         [0008]    In an embodiment of the present invention, a position tracking system comprises a portable electronic device, at least one RFID reader and a remote monitoring server. The portable electronic device has a signal receiving module, a first communicating module, an active radio frequency identification (RFID) tag and a controlling module. The signal receiving module receives a satellite positioning signal in a first region. The first communicating module emits the satellite positioning signal. The active RFID tag emits an identification (ID) code signal. And the controlling module enables/disables the signal receiving module and the active RFID tag. The at least one RFID reader is located in a second region for receiving the ID code signal emitted by the active RFID tag, and emits an radio frequency (RF) positioning signal after receiving the ID code signal. The remote monitoring server comprises a second communicating module and a position determining module. The second communicating module establishes a communicating connection with the first communicating module for receiving the satellite positioning signal emitted by the first communicating module and for receiving the RF positioning signal emitted by the RFID reader. The position determining module uses the satellite positioning signal received by the second communicating module to determine whether the portable electronic device is far from the first region and close to the second region when the controlling module enables the signal receiving module; wherein the remote monitoring server sends a first command via the second communicating module to the first communicating module when the portable electronic device is close to the second region, and the controlling module enables the active RFID tag according to the first command received by the first communicating module. 
         [0009]    In another embodiment of the present invention, a position tracking method is provided for tracking positions of a portable electronic device. The portable electronic device has a signal receiving module to receive a satellite positioning signal in a first region and also has an active RFID tag to send an ID code signal for at least one RFID reader in a second region. The RFID reader sends an RF positioning signal after receiving the ID code signal. The method comprises the following steps. First of all, establish a communicating connection with the portable electronic device. Next, receive the satellite positioning signal sent by the portable electronic device. Then, determine whether the portable electronic device is far from the first region and close to the second region according to the satellite positioning signal; wherein when the portable electronic device is far from the first region and close to the second region, a first command is sent to the portable electronic device to enable the active RFID tag for sending the ID code signal to the RFID reader. Finally, receive the RF positioning signal sent by the RFID reader. 
         [0010]    In another embodiment of the present invention, a portable electronic device is used for communicating with a remote monitoring system. The portable electronic device comprises a signal receiving module, a first communicating module, an active RFID tag and a controlling module. The signal receiving module receives a satellite positioning signal in a first region. The first communicating module establishes a communicating connection with the remote monitoring system and sends the satellite positioning signal to the remote monitoring system. The active RFID tag sends an ID code signal for at least one RFID reader in a second region to read; the RFID reader also sends an RF positioning to the remote monitoring system after reading the ID code signal. And the controlling module enables/disables the signal receiving module and the active RFID tag; wherein when the remote monitoring system determines that the portable electronic device is far from the first region and close to the second region, the remote monitoring system sends a first command to the first communicating module and the controlling module enables the active RFID tag following to the first command received by the first communicating module. 
         [0011]    The major differences between the present invention and the prior art are explained as follows. The present invention provides a portable electronic device that is equipped with different communication modules. The different communication modules capable of retrieving position signals are enabled selectively according to the status/type of position signals of the portable electronic device. All of the different communication modules are enabled when the portable electronic device locates around a boundary between different regions that require different communication modules to obtain geography information. Therefore, by means of seamless transferring operation between different communication modules, a remote manager may be able to continuously monitor the positions of the portable electronic device. 
         [0012]    These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description and appended claims. It is to be understood that both the foregoing general description and the following detailed description are examples, and are intended to provide further explanation of the invention as claimed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The invention will become more fully understood from the detailed description given herein below illustration only, and thus is not limitative of the present invention, and wherein: 
           [0014]      FIG. 1  is a block diagram of the position tracking system according to an embodiment of the invention; 
           [0015]      FIG. 2  is a flowchart of the position tracking method according to an embodiment of the invention; 
           [0016]      FIGS. 3A to 3D  show the format of the command sent from the remote monitoring server to the portable electronic device according to the invention; and 
           [0017]      FIG. 4  is a flowchart of the position tracking method according to another embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]    The present invention will be apparent from the following detailed description, which proceeds with reference to the accompanying drawings, wherein the same references relate to the same elements. 
         [0019]      FIG. 1  is a block diagram of the disclosed position tracking system according to an embodiment of the invention. As shown in the drawing, the position tracking system  100  includes a portable electronic device  110 , at least one radio frequency identification (RFID) reader  120 , and a remote monitoring server  130 . The portable electronic device  110  includes a signal receiving module  112 , a first communicating module  114 , an active RFID tag  116 , and a controlling module  118 . The remote monitoring server  130  includes a second communicating module  132  and a position determining module  134 . It should be noted that the electronic device  110  can be a mobile phone, a personal digital assistant (PDA), or some other electronic device with the communication function. It is not restricted by the invention. 
         [0020]    As described above, the signal receiving module  112 , such as a GPS chip, is used to receive satellite positioning signals emitted by satellites in a first region (outdoor space without building obstacles). The first communicating module  114  is used to send the satellite positioning signals to the remote monitoring server  130 . More explicitly, the satellite positioning signals are transmitted to the remote monitoring server  130  by the third generation mobile communication (3G), general packet radio service (GPRS), wireless fidelity (Wi-Fi), worldwide interoperability for microwave access (Wimax), short message service (SMS) or satellite signals. The invention does not impose any restriction on the way the first communicating module  114  transmits satellite positioning signals. 
         [0021]    The active RFID tag  116  sends identification (ID) code signals for the RFID reader  120  to read. The RFID reader  120  is located in a second region (e.g., indoor space) that the signals emitted by the satellites cannot reach. Moreover, after the RFID reader  120  reads the ID code emitted by the active RFID tag  116 , it sends a radio frequency (RF) positioning signal to the remote monitoring server  130 . The remote monitoring server  130  can obtain the location of the RFID reader  120  according to the RF positioning signal, thereby finding out precisely the location of the user of the electronic device  110 . 
         [0022]    The controlling module  118  controls the on and off states of the signal receiving module  112  and the active RFID tag  116 . The following example describes in detail how the controlling module  118  enables the signal receiving module  112  and the active RFID tag  116 . 
         [0023]      FIG. 2  is a flowchart showing the steps of the position tracking method according to an embodiment of the invention. Please refer simultaneously to  FIGS. 1 and 2 . In the initial state of the portable electronic device  110 , the controlling module  118  first enables the signal receiving module  112 . If the portable electronic device  110  is in the above-mentioned first region at the moment, then the satellite positioning signals from the satellites can be received by the signal receiving module  112 . Moreover, the remote monitoring server  130  establishes communications with the portable electronic device  110  via the second communicating module  132  (step  210 ). The second communicating module  132  receives the satellite positioning signals transmitted by the first communicating module  114  (step  220 ). The location of the portable electronic device  110  is thus obtained. In particular, the remote monitoring server  130  establishes communications with the first communicating module  114  via the second communicating module  132 . 
         [0024]    Afterwards, the remote monitoring server  130  uses the position determining module  134  to determine from the satellite positioning signals whether the portable electronic device  110  is moving from the first region to the second region and close the boundary of the first region (step  230 ). More explicitly, the remote monitoring server  130  stores geography information of the first and second regions. Therefore, the position determining module  134  can use such information to determine whether the portable electronic device  110  is close to the boundary of the first region and about to enter the second region. In the geography information stored in the remote monitoring server  130 , a specific range is defined between the first region and the second region. When the position determining module  134  determines according to the satellite positioning signals continuously received by the second communicating module  132  that the portable electronic device  110  is entering from the first region to this range, the portable electronic device  110  is considered as moving from the first region to the second region. In other words, the position determining module  134  can use the satellite positioning signals continuously received by the second communicating module  132  to determine the motion of the portable electronic device  110 . Therefore, it can determine whether the user of the portable electronic device  110  is going from outdoors to indoors. 
         [0025]    As described above, when the position determining module  134  determines from the satellite positioning signals received by the second communicating module  132  that the portable electronic device  110  is not far from the first region, no action is taken. On the other hand, if the position determining module  134  determines from the satellite positioning signals received by the second communicating module  132  that the portable electronic device  110  is far from the first region and close to the second region, the second communicating module  132  sends a command  131  (as shown in  FIG. 3A ) to the portable electronic device  110 . The controlling module  118  of the portable electronic device  110  follows the command  131  received by the first communicating module  114  to enable the active RFID tag  116  (step  240 ). 
         [0026]    It should be mentioned that the format of the command sent by the second communicating module  134  includes the three fields of a verification number, an executing component, and an executing command. The datum in the verification number field contains the verification number of the portable electronic device that receives the command. The datum in the executing component field contains the component that is supposed to execute the command. The datum in the executing command field contains the command to be executed. In this embodiment, the ID field of the command  131  has the ID code “123456” of the portable electronic device  110 . The executing component field is filled with the active RFID tag. The executing command field is filled with “start,” as shown in  FIG. 3A . 
         [0027]    According to the above description, when the portable electronic device  110  approaches the boundary of the first region and is about to enter the second region, the signal receiving module  112  and the active RFID tag  116  are both on. Therefore, whether the user of the portable electronic device  110  moves toward the first region or the second region at the next moment, the remote monitoring server  130  can immediately obtain his location. 
         [0028]    After the user of the portable electronic device  110  enters the second region, the RFID reader  120  in the second region receives the ID code signal sent from the active RFID tag  116  and transmits an RF positioning signal to the remote monitoring server  130 . The remote monitoring server  130  receives the RF positioning signal via the second communicating module  132  (step  250 ), and thereby finds out the location of the user of the portable electronic device  110 . 
         [0029]    It should be mentioned that after the remote monitoring server  130  receives the RF positioning signal, it sends a command  133  via the second communicating module  132  to the portable electronic device  110 . The controlling module  118  of the portable electronic device  110  follows the command received by the first communicating module  114  to turn off the signal receiving module  112  (step  260 ), thus saving the power consumption of the portable electronic device  110 . The ID field of the command  133  contains the verification number “123456” of the portable electronic device  110 . The executing component field contains the “signal receiving module.” The executing command field is filled with “off,” as shown in  FIG. 3B . 
         [0030]      FIG. 4  is a flowchart showing the position tracking method in another embodiment of the invention. With reference to  FIG. 4 , suppose the initial state of the portable electronic device  110  is in the second region. The controlling module  118  only receives the RF positioning signal. The second communicating module  132  sends a command  133  to the portable electronic device  110 , so that the controlling module  118  of the portable electronic device  110  follows the command  133  received by the first communicating module  114  to turn off the signal receiving module  112  and to enable the active RFID tag  116 . In this case, the RFID reader  120  in the second region receives the ID code signal sent by the active RFID tag  116 , and sends an RF positioning signal to the remote monitoring server  130 . The remote monitoring server  130  receives the RF positioning signal via the second communicating module  132  (step  420 ) and, therefore, obtains the location of the user of the portable electronic device  110 . 
         [0031]    As described above, the communication distance between the RFID reader  120  and the active RFID tag  116  is limited. Therefore, the same second region (i.e., same indoor space) can be provided with several RFID readers  120 . In particular, the position determining module  134  of the remote monitoring server  130  can determine which RFID reader  120  sends out the RF positioning signal received by the second communicating module  132 . Therefore, it can accurately obtain the position of the user of the portable electronic device  110  in the indoor space. Also because of so, the remote monitoring server  130  can determine whether the user of the portable electronic device  110  is moving from the second region toward the first region and close to the boundary of the second region according to the RF positioning signal received by the second communicating module  132  using the position determining module  134  (step  430 ). 
         [0032]    When the position determining module  134  determines that the user of the portable electronic device  110  is close to the boundary of the second region and about to enter the first region, the remote monitoring server  130  sends out a command  135  via the second communicating module  132 . The command  135  is sent to the portable electronic device  110  via the communicating connection established in step  410 . The controlling module  118  of the portable electronic device  110  enables the signal receiving module  112  (step  440 ). In particular, the ID field of the command  135  is filled with the verification number “123456” of the portable electronic device  110 . The executing component field is filled with “the signal receiving module,” and the executing command field is filled with “start,” as shown in  FIG. 3C . 
         [0033]    After the user of the portable electronic device  110  enters the first region, the signal receiving module  112  can receive the satellite positioning signals emitted by satellites. The first communicating module  114  sends the satellite positioning signals to the remote monitoring server  130 . The remote monitoring server  130  uses the second communicating module  132  to receive the satellite positioning signals (step  450 ), thereby determining the location of the user of the portable electronic device  110 . 
         [0034]    As described above, the remote monitoring server  130  can use the second communicating module  132  to transmit the command  137  to the portable electronic device  110 . The controlling module  118  of the portable electronic device  110  disables the active RFID tag  116  according to the command  137  received by the first communicating module  114  (step  460 ), thereby saving the power of the portable electronic device  110 . The ID field of the command  137  is filled with the verification number “123456” of the portable electronic device  110 . The executing component field is filled with “the active RFID”. The executing command field is filled with “off,” as shown in  FIG. 3D . 
         [0035]    When the portable electronic device  110  is at the boundary between the first region and the second region, the controlling module  118  simultaneously enables the signal receiving module  112  and the active RFID tag  116 . Therefore, regardless whether the portable electronic device  110  moves from the boundary between the first region and the second region to the first region or the second region, the remote monitoring server  130  can continuously receive the position information of the portable electronic device  110 . 
         [0036]    With further reference to  FIGS. 1 and 2 , after the user of the portable electronic device  110  moves from the first region to the second region, the position determining module  134  in the remote monitoring server  130  uses the RF positioning signal received in step  250  to determine whether the user of the portable electronic device  110  approaches from the second region to the first region. The detail is illustrated in  FIG. 4 , and is not repeated herein again. 
         [0037]    Likewise, in the flowchart of  FIG. 4 , after the user of portable electronic device  110  moves from the second region to the first region, the position determining module  134  of the remote monitoring server  130  also uses the satellite positioning signals received in step  450  to determine whether the user of the portable electronic device  110  moves from the first region to the second region. The detail is illustrated in  FIG. 2 , and is not repeated herein again. 
         [0038]    In particular, when the communication between the portable electronic device  110  and the remote monitoring server  130  breaks, i.e., when the first communicating module  114  of the portable electronic device  110  cannot transmit the satellite positioning signals received by the signal receiving module  112  to the remote monitoring server  130 , the controlling module  118  of the portable electronic device  110  simultaneously enables the signal receiving module  112  and the active RFID tag  116 . Once the communication between the portable electronic device  110  and the remote monitoring server  130  resumes, the position information of the portable electronic device  110  can be immediately provided to the remote monitoring server  130 . It is worth mentioning that after the controlling module  118  simultaneously enables the signal receiving module  112  and the active RFID tag  116 , the portable electronic device  110  records the coordinates in the satellite positioning signals received by the signal receiving module  112 . Once the portable electronic device  110  and the remote monitoring server  130  subsequently resume the connection, the coordinate information is transmitted to the remote monitoring server  130  to make up information loss when the communication is broken. 
         [0039]    Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments, will be apparent to persons skilled in the art. It is, therefore, contemplated that the appended claims will cover all modifications that fall within the true scope of the invention.