Patent Publication Number: US-2012032844-A1

Title: Real-time location tracking apparatus and method using global positioning system (gps) signal relay tag

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of Korean Patent Application No. 10-2010-0074989 and of Korean Patent Application No. 10-2010-0116739, respectively filed on Aug. 3, 2010, and Nov. 23, 2010 in the Korean Intellectual Property Office, the disclosures of which are incorporated herein by reference. 
     BACKGROUND 
     1. Field of the Invention 
     The present invention relates to a real-time location tracking apparatus and method using a global positioning system (GPS) signal relay tag, and more particularly, to an apparatus and method that may provide a real-time location tracking service to a user terminal using a location server, either by providing tag coordinates and tag information to the location server via a mobile communication network or the Internet after receiving a GPS signal from the GPS signal relay tag, transmitting GPS information and the tag information to the reader, and calculating, by the reader, a location of the tag, or by providing the tag coordinates and tag information to the location server after calculating, by a location processor, the location of the tag by receiving information necessary for the location calculation from the reader via the mobile communication network or the Internet, instead of performing the calculation by the reader. 
     2. Description of the Related Art 
     A global positioning system (GPS) was first developed for military application, and is now being used in various real world applications. In particular, the GPS is being used as a location-based service that may create new added value by merging location information of a user and periphery information through use of a mobile communication terminal such as, a smart phone. The location-based service may be used in various fields, such as a rescue request, a response to a reported crime, a geographical information system providing information of an adjacent area, and traffic information, a vehicle navigation system, logistics information, and the like. 
     A representative positioning method that may provide a location-based service using a GPS receiver mounted on a mobile communication terminal is classified into two schemes, Autonomous GPS and assisted GPS (A-GPS). The Autonomous GPS scheme refers to a scheme of positioning a location of a terminal autonomously in the terminal using a GPS reception antenna in the terminal and a positioning algorithm, without any assistance from a positioning server, and the like. A basic difference between the Autonomous GPS and the A-GPS is that the autonomous GPS communicates directly with a satellite using a GPS receiver in the terminal, whereas the A-GPS receives assistance from a mobile communication network or wireless fidelity (Wi-Fi) network, which is used in the mobile communication terminal. The A-GPS manages an assistance server including information regarding the closest GPS satellite for each region, which may perform communication, and constantly records satellite information. When the GPS terminal encounters difficulty in searching for a satellite signal, the satellite information may be received via the mobile communication network or the Wi-Fi network, and the assistance server may perform user location calculation and revision instead. 
     However, in order to independently calculate the location based on the GPS signal received using the Autonomous GPS, a separate CPU function should be equipped, and also a problem related to power consumption, such as a battery, in a cellular phone may need to be resolved. In the case of the A-GPS, information may be transferred and received via the mobile communication network or the Wi-Fi network, and accordingly a separate communication module, such as a mobile communication module, for example, long term evolution (LTE) second generation (2G), LTE third generation (3G), and the like, a WiFi module, and the like, may be required, which may result in a high terminal price. Accordingly, the A-GPS is generally applied to a smart phone. The location-based service using a mobile communication terminal is generally used as a service for providing location information of a user to the user, or a service for providing the location information of the user to another mobile communication terminal user, for example, a safe return service to report someone arriving safely at home to guardians. 
     The conventional location tracking system using a mobile communication terminal and a mobile communication network is applied to limited service areas, and only users who use an expensive terminal, and uses a great amount of power. 
     SUMMARY 
     An aspect of the present invention provides a real-time location tracking apparatus using a global positioning system (GPS) signal relay tag, which may identify a location of a tag using low power, by relaying a GPS signal via a mobile communication network and the Internet. 
     Another aspect of the present invention also provides a real-time location tracking apparatus and method using a GPS signal relay tag, wherein a tag may output a transmission message frame to a reader by configuring the transmission message frame including identification (ID) information and a GPS signal when the tag is activated and receives the GPS signal, and the reader may receive the output signal of the tag, and may calculate a location of the tag based on the received signal of the tag. 
     Still another aspect of the present invention also provides a real-time location tracking apparatus and method using a GPS signal relay tag, wherein a reader may receive an output signal and a GPS signal of a tag, and may calculate a location of the tag based on time information and location data of the tag. 
     A yet another aspect of the present invention also provides a real-time location tracking apparatus and method using a GPS signal relay tag, wherein a tag may sense a state of surroundings, and may transmit a transmission message frame by incorporating the sensed information into the transmission message frame, and a reader may process the sensed information by receiving the transmission message frame. 
     Further another aspect of the present invention also provides a real-time location tracking apparatus and method using a GPS signal relay tag, wherein a tag may transmit a transmission message frame by encoding the transmission message frame, a reader may receive the encoded transmission message frame, and may extract information included in the transmission message frame by decoding the received transmission message frame. 
     Still another aspect of the present invention also provides a real-time location tracking apparatus and method using a GPS signal relay tag, wherein a condition under which a tag may be activated according to a predetermined condition may be determined, and the tag may transmit a transmission message frame when activated. 
     Still another aspect of the present invention also provides a real-time location tracking apparatus and method using a GPS signal relay tag, which may work conjunctively with a mobile communication network or the Internet by installing a reader in a mobile communication base station or relay station at an Access Point (AP). 
     Still another aspect of the present invention also provides a real-time location tracking apparatus and method using a GPS signal relay tag, wherein a reader may transmit, to a location processor, information regarding time information and location data stored in a transmission message frame of a tag via a mobile communication network or the Internet, and the location processor may calculate a location of the tag. 
     Still another aspect of the present invention provides a real-time location tracking apparatus and method using a GPS signal relay tag, wherein a location processor may calculate a location of a tag based on time information and location data, corresponding to the identical ID information of the tag, received from at least three satellites. 
     Still another aspect of the present invention provides a real-time location tracking apparatus and method using a GPS signal relay tag, wherein a reader may calculate a location of a tag based on information gathered by extracting the information regarding time information and location data stored in a transmission message frame of the tag. 
     Still another aspect of the present invention provides a real-time location tracking apparatus and method using a GPS signal relay tag, wherein a location server may provide a service associated with a location of a tag to a user terminal via a mobile communication network or the Internet. 
     Still another aspect of the present invention provides a real-time location tracking apparatus using a GPS signal relay tag, the apparatus including a tag, positioned in relation to an object, to work conjunctively with a GPS signal received from a satellite, to transmit the received GPS signal to a reader installed in a base station, a relay station, or an Access Point (AP), and to enable calculation of location coordinates of the object by the reader. 
     The tag may transmit, to the reader, ID information intrinsically assigned in advance, along with the GPS signal, thereby enabling matching of the object identified based on the ID information in the reader, with the location coordinates calculated based on the GPS signal. 
     The apparatus may further include a sensing unit to activate the tag when a measurement value of at least one of humidity, illuminance, and temperature around the tag satisfies a predetermined criterion value, and the tag may transmit the GPS signal to the reader when activated. 
     Still another aspect of the present invention provides a real-time location tracking apparatus using a GPS signal relay tag, the apparatus including a reader to receive a transmission message frame from a tag, and a GPS receiver to identify an object where the tag may be positioned, based on ID information extracted from the transmission message frame, and to match the object to location coordinates calculated based on a GPS signal extracted from the transmission message frame. 
     The GPS receiver may calculate the location coordinates by applying time information and location data of the tag in the GPS signal. 
     The GPS receiver may identify the time information and the location data from the GPS signal, and may provide the identified time information and the location data to a location processor via a mobile communication network and the Internet, and the location processor may calculate the location coordinates by applying the time information and the location data. 
     The GPS receiver may extract state information sensed in relation to the peripheral environment of the tag, from the transmission message frame, and may direct a state of the tag by processing the state information. 
     When the transmission message frame is encoded before transmitting, the apparatus may further include a decoding module to decode the encoded transmission message frame. 
     The reader may respectively receive n transmission message frames from n tags positioned in relation to the object, n being a natural number. 
     The apparatus may further include a database to store the location coordinates, and the corresponding object matched with the location coordinates, and the GPS receiver may provide, from the database, the location coordinates corresponding to an object of which inquiry may be requested, in response to the inquiry request for the object. 
     Still another aspect of the present invention provides a real-time location tracking method using a GPS signal relay tag, the method including receiving, by a tag, a GPS signal from a satellite, the tag being positioned in association with an object, and enabling calculation of location coordinates of the object in the reader, when the received GPS signal is transmitted by the tag, to the a base station or relay station including the reader, or an AR 
     The method may further include transmitting, by the tag, ID information associated with identifying of the object, along with the GPS signal, to the reader. 
     The method may further include activating the tag when a measured value of at least one of humidity, illuminance, and temperature around the tag satisfies a predetermined criterion value, and the transmitting may include transmitting the GPS signal to the reader when the tag is activated. 
     According to another aspect of the present invention, there is provided a real-time location tracking method using a GPS signal relay tag, the method including receiving a transmission message frame from a tag, extracting identification (ID) information from the transmission message frame, and identifying an object including the tag based on the extracted ID information, extracting GPS information from the transmission message frame, and obtaining location coordinates using the extracted GPS signal, and matching the obtained location coordinates and the identified object. 
     The obtaining may include calculating the location coordinates by applying time information and location data of the tag in the GPS signal. 
     The obtaining may include providing the time information and the location data of the tag to a location processor, by identifying the time information and the location data of the tag from the GPS signal, and receiving, by a location server, the location coordinates calculated by applying the time information and the location data, from the location processor. 
     The method may further include extracting state information sensed in relation to the peripheral environment of the tag, from the transmission message frame, and directing a state of the tag by processing the state information. 
     When the transmission message frame is encoded before transmitting, the method may further include decoding the encoded transmission message frame. 
     The receiving may include respectively receiving n transmission message frames from n tags positioned in relation to the object, n being a natural number. 
     The method may further include storing, in a database, the location coordinates, and the corresponding object matched with the location coordinates, and providing, by the location server, the location coordinates corresponding to an object of which inquiry is requested, in response to the inquiry request for the object. 
     EFFECT 
     According to embodiments of the present invention, a global positioning system (GPS) signal may be transferred to a location processor by relaying the GPS signal using a GPS signal relay tag via a mobile communication network and the Internet, and a location of a tag may be calculated using low power through location calculation performed by the location processor. Thus, the tag may use a minimum amount of power, and the location processor may calculate the location of the tag. 
     According to embodiments of the present invention, a tag may be activated and may receive a GPS signal, configure a transmission message frame including identification (ID) information and the received GPS signal, and output the configured transmission message frame to a reader, and the reader may receive the output signal of the tag, and may calculate a location of the tag based on the received output signal of the tag. Thus, the tag may receive the GPS signal in an activation state, configure a transmission message frame, and transmit the transmission message frame to the reader, and the reader may calculate the location of the tag based on information included in the transmission message frame. 
     According to embodiments of the present invention, a reader may receive an output signal of a tag and a GPS signal, and may calculate a location of the tag based on time information and location data of the tag. Thus, the reader may receive information necessary for location calculation, and may calculate the location of the tag based on the received information. 
     According to embodiments of the present invention, a tag may sense a state of the peripheral environment, and may transmit a transmission message frame by incorporating the sensed information into the transmission message frame, and a reader may receive the transmission message frame of the tag, and may process the sensed information. Thus, the reader may collect and use the information regarding the peripheral environment of the tag. 
     According to embodiments of the present invention, a tag may transmit a transmission message frame by encoding the transmission message frame, and a reader may receive the transmitted message frame, and may extract information included in the transmission message frame by decoding the encoded transmission message frame. Thus, the tag may transmit the encoded data to the reader, and accordingly a data transmission channel with enhanced security between the tag and the reader may be configured. 
     According to embodiments of the present invention, a condition under which a tag may be activated according to a predetermined condition may be determined, and the tag may transmit a transmission message frame when activated. Thus, the tag may configure the transmission message frame, and may transmit the transmission message frame to the reader when the specific condition is satisfied, and accordingly may use a minimum power, and a battery equipped in the tag, having a limited capacity, may be used for a relatively long period of time. 
     According to embodiments of the present invention, a reader may transmit, to a location processor, information regarding time information and location data stored in a transmission message frame of a tag, via a mobile communication network or the Internet, and the location processor may calculate a location of the tag. Thus, the location processor may perform the task of calculating the location of the tag so that a location information service may be provided in a short time. 
     According to embodiments of the present invention, a location processor may calculate a location of a tag based on time information and location data received from at least three satellites, with respect to the identical ID information of the tag. Thus, an accuracy of the location calculation performed by the location processor may be improved. 
     According to embodiments of the present invention, a reader may extract information regarding time information and location data stored in a transmission message frame of a tag, and may calculate a location of the tag based on the extracted information. Thus, a high speed calculation function performed by the reader may be allocated and used for calculating the location of the tag. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and/or other aspects, features, and advantages of the invention will become apparent and more readily appreciated from the following description of exemplary embodiments, taken in conjunction with the accompanying drawings of which: 
         FIG. 1  is a diagram illustrating a configuration of a real-time location tracking apparatus using a global positioning system (GPS) signal relay tag according to an embodiment of the present invention; 
         FIG. 2  is a diagram illustrating a configuration of a GPS signal relay tag according to an embodiment of the present invention; 
         FIG. 3  is a flowchart illustrating an operational sequence of a GPS signal relay tag according to an embodiment of the present invention; 
         FIG. 4  is a function block diagram illustrating a security tag for a satellite relay and environment monitor according to an embodiment of the present invention; 
         FIG. 5  is a diagram illustrating a configuration of a GPS signal relay tag according to another embodiment of the present invention; and 
         FIG. 6  is a diagram illustrating a reader according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. Exemplary embodiments are described below to explain the present invention by referring to the figures. 
       FIG. 1  is a diagram illustrating a configuration of a real-time location tracking apparatus using a global positioning system (GPS) signal relay tag according to an embodiment of the present invention. 
     Referring to  FIG. 1 , the apparatus may include a satellite  110 , a GPS signal relay tag  120 , a reader  130 , a base station  140 , an Access Point (AP)  145 , the Internet  150 , a location processor  160 , a location server  170 , and a user terminal  180 . 
     The satellite  110  may periodically transmit a GPS signal including time information and location information of the satellite  110  at a point in time. 
     The GPS signal relay tag  120  may receive the GPS signal, and may allocate calculation of a location of a tag to the reader  130  that may be installed in the base station  140  or the AP  145 , based on information included in the received GPS signal. The GPS signal relay tag  120  may transfer, to the reader  130 , the time information and identification (ID) information received from the satellite  110 , excluding location data included in the GPS signal, such as the location information of the satellite. 
     The reader  130  either may perform location calculation based on the information received from the GPS signal relay tag  120 , or may transfer, to the location processor  160 , the information received from the GPS signal relay tag  120  without calculating the location. 
     As an example, the reader  130  may calculate the location of the tag based on the location data extracted from the GPS signal using a GPS reception module, the time information received from the GPS signal relay tag  120 , and the ID information of the tag. The location information of the tag calculated by the reader  130  may be transferred to the location processor  160  via a mobile communication network or the Internet  150 . The location server  170  may access the location process  160 , and may obtain the location information of the tag stored in a storage medium, thereby providing, to the user terminal  180 , a location-based service corresponding to an applied field. The user terminal  180  may include wired and wireless communication devices, such as a cellular phone, a PC, a TV, and the like. 
     As another example, the reader  130  may receive the time information and the ID information from the GPS signal relay tag  120 , and may transfer, to the location processor  160 , the received information via a mobile communication network and the Internet  150 . In this instance, the reader  130  may constantly transfer location data to the location processor  160  by extracting the location data from the GPS signal using the GPS reception module. The location processor  160  may calculate longitude and latitude coordinates of the tag based on the location data. The location server  170  may access the location process  160 , and may obtain the location information of the tag stored in a storage medium, thereby providing, to the user terminal  180 , a location-based service corresponding to an applied field, for example, property management, parking lot management, safe return of children to a home, patient management, and the like. 
     The user terminal  180  may monitor the location of the GPS signal relay tag  120  via a mobile communication network, and the Internet  150 . When the user terminal  180  corresponds to a mobile communication terminal, the location information of the GPS signal relay tag  120 , and additional data information may be received through communication with the base station  140 . When the user terminal  180  corresponds to a wireless data terminal, such as WiBro, wireless fidelity (WiFi), Bluetooth, and the like, the location information of the GPS signal relay tag  120 , and the additional data information may be received through a wireless data AP. When the user terminal  180  corresponds to a wired terminal, such as an Internet Protocol television (IPTV), the location information of the GPS signal relay tag  120 , and the additional data information may be received through the wired Internet network. 
       FIG. 2  is a diagram illustrating a configuration of a GPS signal relay tag  200  according to an embodiment of the present invention. 
     Referring to  FIG. 2 , the GPS signal relay tag  200  may include a GPS reception module  210 , a baseband module  220 , and a GPS signal relay transmission module  230 . 
     The GPS reception module  210  may transmit, to the baseband module  220 , time information obtained by decoding a GPS signal received from a satellite. 
     The baseband module  220  may generate a transmission message frame by incorporating the time information and location information of the satellite, received from the satellite, and ID information of the tag, and may perform an encoding task. 
     The GPS signal relay transmission module  230  may externally transmit a carrier frequency via an antenna by incorporating an encoding signal generated by the baseband module  220 , and a Cyclic Redundancy Check (CRC) carrier wave into the carrier frequency. 
       FIG. 3  is a flowchart illustrating an operational sequence of a GPS signal relay tag according to an embodiment of the present invention. 
     The method performed by the GPS signal relay tag may be configured by the GPS signal relay tag as described in the foregoing with reference to  FIG. 2 . The following description is provided to assist the reader in gaining a sufficient understanding of the present invention by providing the description with reference to  FIG. 3 , along with  FIG. 2 . 
     In operation  310 , the GPS signal relay tag may be operated in a sleep mode for a majority of time, and accordingly may use a minimum power. 
     In operation  320 , the GPS signal relay tag may be activated when the power is switched on, and may receive a GPS signal through a GPS reception module. 
     In operation  330 , the GPS signal relay tag may operate a baseband module to generate a transmission message frame including ID information of the tag in addition to time information and location information of a satellite, included in the GPS signal received through the GPS reception module. 
     In operation  340 , the GPS signal relay tag may operate a GPS signal relay transmission module to transmit the generated transmission message frame to a reader. 
       FIG. 4  is a function block diagram illustrating a security tag for a satellite relay and environment monitor according to an embodiment of the present invention. 
     The security tag of  FIG. 4  may include a GPS reception module  410 , a baseband module  420 , and a GPS signal relay transmission module  430 , which may have the same configuration, and perform the same functions of the GPS signal relay tag of  FIG. 2 . The security tag of  FIG. 4  may further include an environment sensing signal module  440 , and an encoding module  450  for performing additional functions. 
     The environment sensing signal module  440  may sense a state of the peripheral environment using a sensor, and may transmit corresponding data to the baseband module  420  by converting the sensed information into data. The baseband module  420  may include at least one of a humidity sensor, an illuminance sensor, and a temperature sensor in order to activate the tag according to a specific environmental condition, and may output the transmission message frame to the GPS signal relay transmission module  430  when the tag is activated. The GPS signal relay transmission module  430  may externally transmit a carrier frequency via an antenna by incorporating an encoding signal generated by the baseband module  420 , and a CRC carrier wave into the carrier frequency. 
     The encoding module  450  may prevent an exposure of the transmission data by encoding the data to be transmitted before the GPS signal relay transmission module  430  transmits the data. 
       FIG. 5  is a diagram illustrating a configuration of a GPS signal relay tag  500  according to another embodiment of the present invention. The configuration and an operation of the GPS signal relay tag  500  will be described hereinafter. 
     The tag  500  may be positioned in relation to an object, and may receive a GPS signal from a satellite through a GPS reception module  510 . The tag  500  may transmit the received GPS signal to a reader. The reader may calculate location coordinates of the object based on the GPS signal received from the tag  500 . 
     The tag  500  may transmit the received GPS signal, and ID information intrinsically assigned in advance, to the reader through a transmission module  520 . The reader may match the object identified based on the ID information, and the location coordinates calculated based on the GPS signal. 
     The tag  500  may operate a sensing unit  530  to switch to an active mode when a measurement value of at least one of humidity, illuminance, and temperature around the tag  500  satisfies a predetermined criterion value. The tag  500  may transmit the GPS signal to the reader when a sleep mode is switched to the active mode. The reader may calculate the location coordinates of the object based on the received GPS signal. 
       FIG. 6  is a diagram illustrating a reader  600  according to an embodiment of the present invention. The configuration of the reader  600 , and operations of each element of the reader  600  will be described hereinafter. Referring to  FIG. 6 , the reader  600  may include a tag reception unit  610 , a GPS reception unit  620 , a decoding module  630 , and a database  640 . 
     The tag reception unit  610  may receive, from a tag, a transmission message frame including a GPS signal and ID information. The tag reception unit  610  may transfer, to the GPS reception unit  620 , the transmission message frame received from the tag. 
     The GPS reception unit  620  may identify an object where the tag may be positioned, based on the ID information extracted from the transmission message frame, and may match the object and location coordinates calculated based on the GPS signal extracted from the transmission message frame. 
     As an example, the GPS reception unit  620  may calculate the location coordinates by applying time information and location data of the tag for the GPS signal, received by the tag, included in the transmission message frame. 
     As another example, the location coordinates of the tag may be calculated by a location processor, instead of the GPS reception unit  620 . The GPS reception unit  620  may identify the time information and the location data of the tag from the GPS signal, and may provide the identified time information and location data to the location processor. The location processor may calculate the location coordinates of the tag based on the time information and the location data received from the GPS reception unit  620 , and may provide the calculated location coordinates to the GPS reception unit  620 . 
     The tag may transfer, to the reader  600 , a transmission message frame by incorporating state information sensed in relation to the peripheral environment, into the transmission message frame. The GPS reception unit  620  of the reader  600  may extract the information sensed in relation to the peripheral environment from the transmission message frame, and may processing the state information to report a state of the tag. 
     When an encoded transmission message frame is received from the tag, the reader  600  may decode the encoded transmission message frame through the decoding module  630 . The reader  600  may calculate the location coordinates of the tag based on the GPS signal of the tag, included in the decoded transmission message frame. 
     The tag reception unit  610  may respectively receive transmission message frames from a plurality of tags positioned in relation to objects. The tag reception unit  610  may receive the plurality of transmission message frames from the tags, and may transfer the plurality of transmission message frames to the GPS reception unit  620 . Here, the GPS reception unit  620  may calculate locations of the tags based on GPS signals received by each of the tags, included in the plurality of transmission message frames. 
     The GPS reception unit  620  may store the calculated locations of the tags, and the corresponding objects in the database  640 . The GPS reception unit  620  may provide, from the database, location coordinates corresponding to the objects of which inquiries may be requested, in response to the inquiry requests for the objects. 
     The above-described exemplary embodiments of the present invention may be recorded in computer-readable media including program instructions to implement various operations embodied by a computer. The media may also include, alone or in combination with the program instructions, data files, data structures, and the like. Examples of computer-readable media include magnetic media such as hard disks, floppy disks, and magnetic tape; optical media such as CD ROM discs and DVDs; magneto-optical media such as optical discs; and hardware devices that are specially configured to store and perform program instructions, such as read-only memory (ROM), random access memory (RAM), flash memory, and the like. Examples of program instructions include both machine code, such as produced by a compiler, and files containing higher level code that may be executed by the computer using an interpreter. The described hardware devices may be configured to act as one or more software modules in order to perform the operations of the above-described exemplary embodiments of the present invention, or vice versa. 
     Although a few exemplary embodiments of the present invention have been shown and described, the present invention is not limited to the described exemplary embodiments. Instead, it would be appreciated by those skilled in the art that changes may be made to these exemplary embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.