Patent Publication Number: US-2007099626-A1

Title: Tracking system and method

Description:
FIELD OF THE INVENTION  
      The present invention relates generally to the position determination field, and more particularly, but not exclusively, to a system and method for determining and communicating the precise location of an individual and/or a vehicle.  
     BACKGROUND OF THE INVENTION  
      There is a substantive, continuing need to improve the safety and security of individuals. However, there are a number of problems related to individual safety and security that arise as a result of not knowing the precise location of individuals and/or their motor vehicles at particular points in time. Notably, if a person is lost, or stranded with a motor vehicle at an unknown location, or a motor vehicle is stolen or car-jacked, then an acquaintance or the family of that person, the owner of that vehicle, and/or the police would want to know the precise location of that person or vehicle as quickly as possible. Admittedly, within the last five years, cellular phone use has become as common as owning a television set. Consequently, if an average person is stranded but knows their precise location (e.g., intersection of K Street and Fifth Avenue), then that person can relay that information to someone else with a cellular phone. However, a significant problem in this regard is that if the person is lost or the motor vehicle is stolen, then a cellular phone is not particularly useful in ascertaining the location of that person or vehicle. Therefore, it would be advantageous to have a system and method that can determine and communicate to another the precise location of an individual and/or motor vehicle in real-time, which is also relatively easy to implement by an average person. As described in detail below, the present invention provides such a system and method, which resolves the existing individual and/or vehicle location determination and communication problems and similar other problems.  
     SUMMARY OF THE INVENTION  
      The present invention provides a system and method for determining and communicating the precise location of an individual and/or a motor vehicle in real-time. In accordance with a preferred embodiment of the present invention, a tracking system is provided that includes a Global Positioning System (GPS) receiver, a cellular phone, and a processing unit. The GPS receiver, cellular phone and processing unit are arranged as a single, compact tracking unit. The processing unit receives precise location information (e.g., latitudinal and longitudinal coordinates) for the tracking unit from the GPS receiver. A cellular phone capable of receiving text messages (e.g., and/or voice messages) can be used to call the cellular phone of the tracking unit, which responds (e.g., to an authenticated call) by transmitting a text message (e.g., or synthesized voice message) including the precise coordinates of the tracking unit. Thus, either with or without the knowledge of the individual carrying the tracking unit or driving the motor vehicle containing the tracking unit, the present invention is capable of providing the exact location of the individual and/or motor vehicle to another at any point in time.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:  
       FIG. 1  depicts a block diagram of an example system for determining and communicating the location of an individual and/or vehicle, which can be used to implement a preferred embodiment of the present invention; and  
       FIGS. 2A and 2B  depict related flow charts showing an exemplary method for determining and communicating to another the precise location of an individual and/or vehicle in real-time, in accordance with a preferred embodiment of the present invention.  
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT  
      With reference now to the figures,  FIG. 1  depicts a block diagram of an example system  100  for determining and communicating the location of an individual and/or vehicle, which can be used to implement a preferred embodiment of the present invention. For this example embodiment, system  100  includes a cellular telephone unit  102  coupled to a cellular telephone antenna  104  for transmitting and receiving calls (e.g., via a commercially available cellular network). However, although unit  102  is disclosed herein as a cellular telephone for this example embodiment, the present invention is not intended to be so limited and can include within its scope of coverage any suitable type of mobile or wireless device that can receive and recognize a plurality of alphanumeric symbols (e.g., keyed-in numbers) and/or vocal commands (e.g., spoken numbers), and also transmit a plurality of text messages and/or predetermined voice messages (e.g., “current location is such and such latitude, such and such longitude”, etc.). Also, although system  100  is described herein primarily in the context of determining and communicating the location of an individual or motor vehicle, the present invention can include within its scope of coverage other types of vehicles, such as, for example, boats, aircraft, trains, etc.  
      For this example embodiment, system  100  also includes a GPS receiver unit  106  coupled to a GPS antenna  108  for receiving signals continuously from a plurality of on-orbit satellite transmitters, and converting those signals to coordinate data (e.g., latitude and longitude) that describes the precise location of system  100  at any point in time. Notably, although unit  106  is described herein as a GPS receiver for this example embodiment, the present invention is not intended to be so limited and can include within its scope of coverage any suitable type of navigation receiver that can produce location information that is substantially as precise as GPS-derived location information. In any event, for this example embodiment, an output of GPS receiver unit  106  is coupled to an input of a digital control unit  110 . Also, cellular telephone unit  102  is coupled to digital control unit  110  so that data (e.g., control data, received data, text message data, etc.) can be transferred to/from cellular telephone unit  102  from/to digital control unit  110 . As such, digital control unit  110  can be implemented with a suitable digital processor and/or control unit such as, for example, a microprocessor or microcontroller disposed on a semiconductor chip. Additionally, a DIP switch unit  114  is connected to an input of digital control unit  110 , so that a user of system  100  can set a plurality of the switches of DIP switch unit  114  in a combination that forms an authentication or security code that can be recognized and stored by digital control unit  110  in an associated memory device.  
      For this example embodiment, cellular telephone unit  102 , GPS receiver unit  106 , and digital control unit  110  are each connected to a power supply unit  112 . Power supply unit  112  is electrically connected to an external power source (e.g., 12V battery of a host motor vehicle, or similar external power source) and a battery backup unit  116 . For example, battery backup unit  116  can include a lithium-ion battery that can provide low power levels for components of system  100  over extended periods of time. Thus, power supply unit  112  can function as a regulator/switching device, which supplies power at suitable levels to cellular telephone unit  102 , GPS receiver unit  106  and digital control unit  110  from the external power source (e.g., motor vehicle battery) whenever the external power is available, or from battery backup unit  116 . Power supply unit  112  can also function as a battery charger, which recharges battery backup unit  116  (e.g., a conventional rechargeable battery) while the external power is available, so that system  100  can operate, if necessary, as a standalone unit. In other words, if system  100  is disconnected from the external power source, then system  100  can continue to operate (e.g., at reduced power levels) as a standalone unit for an extended period of time. As such, system  100  can be maintained for an extended period in a standby mode at reduced power, and digital control unit  110  will not enable the transmitter of cellular telephone unit  102  until, for example, an authenticated call is received by cellular telephone unit  102  and a reply message (e.g., including location information) is to be transmitted.  
      For this example embodiment,  FIG. 1  also shows a cellular telephone unit  118 , which can be used to communicate with cellular telephone unit  102  via a radio link  120  (e.g., cellular network) and antennas  104  and  122 . Notably, although units  102  and  118  are described as cellular telephones for this embodiment, the present invention is not intended to be so limited and can also include other types of wireless communication devices (e.g., wireless radiotelephones, mobile radios, etc.) for two-way communications. As such, it is preferable that the communication device used for unit  118  is a mobile (as opposed to a fixed location) two-way communication device. However, although less preferable, for another embodiment, a fixed, land-line telephone may also be used for unit  118  in order for a user to call and communicate with cellular telephone unit  102 .  
      Essentially, in operation for this example embodiment, a user (e.g., operator, purchaser, owner, etc.) of system  100  initially contacts a cellular telephone service provider and receives a unique, non-published (private) telephone number assigned to cellular telephone unit  102 . The user (or telephone service provider) then enters a security/authentication code into system  100  by setting a suitable combination of switches in DIP switch unit  114 . The switch settings (security/authentication code) are received by digital control unit  110 , which stores the code data in an associated memory device. Notably, it should be understood that although DIP switch unit  114  is used for entering a security code in this example embodiment, the present invention is not intended to be so limited, and can include any other suitable technique for entering and storing a security/authentication code in system  100  (e.g., user connects a personal computer to system  100  via a USB connector and enters a security code to digital control unit  110  via the personal computer&#39;s keyboard, etc.).  
      In any event, the user may connect system  100  to an external power source (e.g., host motor vehicle battery) or operate system  100  on internal power as a standalone unit (e.g., personal carry). In order to determine the precise location of system  100  (and the host vehicle, person carrying the unit, etc.), a user (e.g., using communication unit  118 ) calls the telephone number assigned to cellular telephone unit  102 . At this point, digital control unit  110  instructs cellular telephone unit  102  to enable the transmitter and transmit a reply (e.g., audible beep) to prompt the caller to reply with a valid security or authentication code (e.g., keyed-in number sequence). Only if digital control unit  110  recognizes the keyed-in number sequence as a valid code (e.g., matches switch settings in DIP switch unit  114 ), then digital control unit  110  retrieves from local memory the most current location information from GPS receiver unit  106 , formulates a text message including the most current location information, and instructs cellular telephone unit  102  to transmit the text message to the authenticated caller (e.g., via radio link  120  to communication unit  118 ). If a movement history is desired, system  100  can also include in the text message suitable information about past locations (e.g., the past  5  locations where system  100  did not move for a predetermined interval of time). Therefore, except for the slight delay in placing the call, system  100  can, in real-time, provide for an authenticated (e.g., mobile) caller the precise location (and movement history) of system  100 , a host vehicle for system  100 , and/or an individual carrying system  100 . If desired, unit  118  can also be implemented with a display suitable for showing a representative map and the current location of system  100  on that map (e.g., unit  118  can include graphics software to generate such a map, analyze the coordinate data received from system  100 , and thus display the location of system  100  on that map).  
       FIGS. 2A and 2B  depict related flow charts showing an exemplary method  200  for determining and communicating to another the precise location of an individual and/or vehicle in real-time, in accordance with a preferred embodiment of the present invention. For this example embodiment, method  200  represents an algorithm that can be implemented as software instructions executed by a microprocessor or microcontroller, such as, for example, digital control unit  110  in  FIG. 1 . As such, referring to  FIGS. 1, 2A  and  2 B for this example, system  100  is powered on (step  202  of  FIG. 2A ). Next, digital control unit  110  begins to initialize the operation of system  100 , by retrieving initial operating environment variables from read-only memory (e.g., EEPROM) and storing that data in system memory (RAM) for initial execution. Using the stored environment variables data, digital control unit  110  then initializes the peripheral interfaces between each of the units (e.g.,  102 - 116 ) in system  100  (step  204 ). Next, digital control unit  110  receives new coordinate data from GPS receiver unit  106  (step  206 ). Digital control unit  110  then stores the received GPS coordinate data (e.g., along with a time stamp) in system memory (step  208 ). Next, for this example embodiment, if system  100  is operating in a “low power mode” (e.g., not yet determined at this point), digital control unit  110  stores the location data only when movement of system  100  is detected. Otherwise, for example, the location data can be stored in memory at fixed intervals and retrieved at any time. As such, an operation to determine whether system  100  is in a “low power mode” involves a step of checking a flag that is set when the “low power mode” subroutine is executed, as illustrated by element  220  in  FIG. 2A  and elements  210   a, b, c  in  FIGS. 2A and 2B .  
      Next, digital control unit  110  determines by a suitable signal received from power supply unit  112  whether or not external power (e.g., 12V from a motor vehicle) is applied (step  212 ). If so, then digital control unit  110  instructs power supply unit  112  to couple the (regulated) external power to battery backup unit  116  in order to maintain a suitable charge on the internal battery. Notably, for this example embodiment, digital control unit  110  continuously monitors power supply unit  112  to determine whether or not the external power is applied.  
      If power supply unit  112  experiences a voltage loss condition, an immediate transition to battery backup power is made by the hardware. Additionally, a suitable signal is set (e.g., signal associated with the voltage loss condition), which is monitored by digital control unit  110 . Thus, if (at step  212 ) digital control unit  110  determines that the external power is not applied or has failed, then (at element  210   b ) the “low power mode” flag is verified. If this flag is already set, the power loss condition was previously processed, so the flow continues back to step  214  of  FIG. 2A . If this flag is not set, then flow proceeds to the “low power mode” subroutine  1  (e.g., beginning with element  220  in  FIG. 2A ). This procedure sets the necessary flags that are checked in other parts of the main routine in  FIG. 2A , and then digital control unit  110  begins execution of the steps in subroutine  1  (elements  210   a, b, c  in  FIG. 2B ).  
      For data security, digital control unit  110  immediately copies pertinent data from the volatile system memory (e.g., RAM) to a suitable internal, non-volatile memory device. Next, to conserve power, digital control unit  110  responds only to request messages for location information received by cellular telephone unit  102 , which are accompanied by a predetermined “emergency code” (step  236 ). This procedure is again verified by checking a flag that is set during execution of the “low power mode” subroutine. For this example embodiment, if system  100  is operating in the “low power mode”, only emergency location request messages will be answered. For example, digital control unit  110  can continuously monitor cellular telephone unit  102  to determine whether or not cellular telephone unit  102  has received a location request message marked with an appropriate “emergency code”. Until such an “emergency” message is received, system  100  can operate in a low power, standby mode.  
      In any event, for this example embodiment, digital control unit  110  creates a message at step  222  of  FIG. 2A  (e.g., corresponding to step  238  in subroutine  1  of  FIG. 2B ), including a suitable “power loss” statement along with the current location information derived from GPS receiver unit  106  (step  238 ). The “power loss” message is transmitted via cellular telephone unit  102  and antenna  104  (step  224 ). Subsequently, this “power loss” message is created and transmitted only in response to a location request received and accompanied by the appropriate “emergency code”.  
      Returning to step  214  for this example embodiment, digital control unit  110  determines whether or not a new location request message has been received by cellular telephone unit  102  (step  214 ). If not, then flow returns to step  206 . However, if (at step  214 ) a new location request message is received by cellular telephone unit  102 , then digital control unit  110  interrupts the current operational mode and issues a “decode” command, which prompts system  100  to await the receipt (e.g., via cellular phone unit  102 ) of a security code (e.g., entered by the caller). Additionally, the “low power mode” flag is checked. If this flag is set, further message processing will continue only if the request message is marked with an “emergency code”.  
      Next, digital control unit  110  decodes the portion of the request message that should contain the security code. If such a code is received (e.g., from the caller), digital control unit  110  then determines whether or not the received code is correct, by matching it with the code sequence from the switch settings in DIP switch unit  114  (step  226 ). If the received code is incorrect (e.g., does not match the switch settings), then digital control unit  110  determines whether or not a predetermined number (e.g., 3) of incorrect codes have been received (step  230 ). If a correct code is received from the caller within the predetermined number of attempts, then digital control unit  110  updates and/or resets a (security code) counter (step  232 ), and the flow returns to step  206 .  
      Returning to step  226 , if digital control unit  110  determines that a correct authentication/security code has been received within the allotted number of attempts, digital control unit  110  enables the transmitter stage of cellular phone unit  102 . Digital control unit  110  then determines whether or not a valid command (e.g., “send position coordinates”) has been received via cellular phone unit  102 . If so, then digital control unit  110  processes the message request (step  228 ), by retrieving stored position coordinate data (e.g., depending on the power mode of system  100 , either from RAM or nonvolatile memory), and constructing a suitable text response message including the retrieved coordinate data (step  222 ). Alternatively, for example, digital control unit  110  can construct a suitable text message or voice message including the position coordinate data using a digital voice synthesizer. Digital control unit  110  then forwards the message to cellular telephone unit  102 , which transmits the message for receipt by the caller&#39;s phone (step  224 ). Next, for this example, in order to conserve power if system  100  is operating in a “low power mode, digital control unit  110  disables the transmitter stage of cellular telephone unit  102 , and flow returns to step  206 .  
      Returning to step  230  of  FIG. 2A , if digital control unit  110  determines that more than the predetermined number (e.g., 3) of security/authentication code mismatches have occurred, then digital control unit  110  sets a “locked-down mode” flag (step  234 ), and (at element  216   b ) executes the “locked-down mode” subroutine. Thus, referring to element  216  in  FIG. 2B , digital control unit  110  creates a suitable “security violation” report message, and sends that message (via cellular telephone unit  102 ) to a predetermined phone (step  244 ). For example, the predetermined phone can be the home phone for a person accompanying system  100 . Notably, if system  100  is also operating in the “low power mode”, digital control unit  110  can enable the transmitter stage of cellular telephone unit  102  solely for the purpose of sending the “security violation” message. In any event, for a predetermined interval of time (e.g., 30 minutes), digital control unit  110  can deny (e.g., not respond to) incoming location request messages. After the predetermined time interval has expired, or for example, if a valid call is received from the predetermined (home) phone, digital control unit  110  resets the counter associated with the security code (step  246 ). The “locked-down mode” subroutine is then terminated (step  248 ), and flow returns to step  206  in  FIG. 2A .  
      It is important to note that while the present invention has been described in the context of a fully functioning position determination and communication system and method, those of ordinary skill in the art will appreciate that the processes of the present invention are capable of being distributed in the form of a computer readable medium of instructions and a variety of forms and that the present invention applies equally regardless of the particular type of signal bearing media actually used to carry out the distribution. Examples of computer readable media include recordable-type media, such as a floppy disk, a hard disk drive, a RAM, CD-ROMs, DVD-ROMs, and transmission-type media, such as digital and analog communications links, wired or wireless communications links using transmission forms, such as, for example, radio frequency and light wave transmissions. The computer readable media may take the form of coded formats that are decoded for actual use in a particular position determination and communication system and method.  
      The description of the present invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. These embodiments were chosen and described in order to best explain the principles of the invention, the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.