Patent Publication Number: US-2006012474-A1

Title: People-locating system and method used in stationary environment utilizing ultra wideband technology

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a people-locating system and method used in a stationary environment utilizing the ultra wideband (UWB) technology and, more particularly, to a people-locating system and method used in a stationary environment utilizing the UWB wireless transmission technique for data transmission.  
      2. Description of Related Art  
      Along with enhancement of living quality, modern people more and more appreciate leisure time. They usually go to some stationary environments, traveling or exercising in places such as amusement parks, parks, shopping malls, and exhibition halls. Because there is more time for parents and children to spend time together, good family relationships can be developed. In these stationary environments, however, adults may easily neglect the whereabouts of children, and lose their children. In these large stationary environments with many tourists, searching for a lost child is very difficult, and the search process is time and labor-consuming.  
      The ultra wideband (UWB) technology is a short-distance wireless communications technology developed by the U.S. military. Compared with other short-distance communications standards, the data rate of the 802.11b standard is only 5/1000 of that of the UWB technology. The first generation UWB technology has a transmission speed of 100 MB/s, and the second generation UWB technology has a transmission speed as high as 400 MB/s. The UWB technology is also immune to interference, accurate in positioning, and has high data transmission safety.  
      In order to prevent communications from being monitored by advanced wiretap techniques, the U.S. military developed the UWB technology, which was also called “invisible wave” in the past. Most wireless transmissions are accomplished with narrowband. For instance, the bandwidth used by mobile phones is about 100 MHz. The bandwidth of the UWB technology is several tens of thousands of MHz. Even if the occupied bandwidth is infiltrated, inventors of this technology claims there will be no interference because its power consumption is very low.  
     SUMMARY OF THE INVENTION  
      An object of the present invention is to provide a people-locating system and method making use of the UWB wireless transmission technique in a short distance to build a people-locating system in a stationary environment.  
      The present invention is used in a stationary environment, and has at least a UWB node distributed in the stationary environment. Moreover, the short-distance wireless communications ranges of these UWB nodes are distributed in a cellular form and cover the whole stationary environment.  
      Moreover, these UWB nodes are connected to a system controller to receive a control signal output by the system controller. After these UWB nodes receive the control signal, the UWB wireless transmission technique is used to perform an inquiry action. These UWB nodes output inquiry signals to at least a UWB emitter located on users to obtain reply signals output by these UWB emitters, respectively. The reply signal is an ID data of the UWB emitter.  
      The system controller can acquire the location of a user in the stationary environment. The location is in the wireless communications range of these UWB nodes. Therefore, if a lost user is to be searched for, the system controller can be operated to output the control signal to these UWB nodes distributed in the stationary environment. These UWB nodes will output inquiry signals to obtain a reply signal output by a UWB emitter located on the lost user in the short-distance wireless communications range.  
      After the UWB nodes obtain a reply signal output by the UWB emitter located on the lost user, the reply signal will be sent to the system controller. The system controller will thus acquire the location of the lost user in the short-distance wireless communications range.  
      The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawings, in which: 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The foregoing aspects and many of the attendant advantages of this invention will be more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:  
       FIG. 1  is a an operation environment diagram of a people-locating system of the present invention;  
       FIG. 2  is an architecture diagram of a people-locating system of the present invention;  
       FIG. 3  is a circuit block diagram of a UWB emitter of a people-locating system of the present invention;  
       FIG. 4  is a circuit block diagram of a UWB node of a people-locating system of the present invention;  
       FIG. 5  is a circuit block diagram of a system controller of a people-locating system of the present invention; and  
       FIG. 6  is a flowchart of a people-locating method of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      The present invention can apply to a stationary environment such as an amusement park, a shopping mall, an exhibition hall or a park. As shown in  FIG. 1 , the present invention applies to an amusement park. A system controller  1  is disposed at the entrance of the amusement park. UWB nodes  2  are disposed in amusement facilities and specific regions. These UWB nodes  2  are used for short-distance wireless communications, are distributed in a cellular form, and cover the whole amusement park.  
      After a user (a tourist) buys a ticket, he gets a UWB emitter  3  (e.g., a small decoration). An ID data is set for each UWB emitter  3 . After the user gets the UWB emitter  3 , an attendant uses the system controller  1  to perform a registration process for registering a user data of the UWB emitter  3  and the ID data of the UWB emitter  3 .  
      The above user data is a start use time, an expenditure type or an expenditure process. Moreover, the attendant can get a photograph of the user via a digital still camera. The photograph data can be stored with the start use time, the expenditure type or the expenditure process in the system controller  1 .  
      Reference is made to  FIG. 2  as well as  FIG. 1 . The attendant uses the system controller  1  to output a control signal to at least a UWB node  2  connected with the system controller  1 , thereby activating these UWB nodes to output an inquiry signal to at least a UWB emitter  3 . These UWB emitters  3  are within the short-distance wireless communications range of these UWB nodes  2 . These UWB nodes  2  acquire in turn the ID data emitted by these UWB emitters  3  and send the ID data to the system controller  1  at the same time.  
      As shown in  FIG. 3 , the UWB emitter  3  comprises a data processing unit  30 , a first UWB communications module  32 , a first antenna  34  and a storage unit  36 .  
      The storage unit  36  of the UWB emitter  3  is connected to the data processing unit  30  and used to store an ID data. The first UWB communications module  32  connected to the data processing unit  30  receives a remote inquiry signal via the first antenna  34  and send the inquiry signal to the data processing unit  30  for digital signal processing. After processing, the data processing unit  30  sends the ID data to the first UWB communications module  32 , which emits a reply signal to a remote UWB node via the first antenna  34 , as shown in  FIG. 2 . The reply signal is the ID data.  
      As shown in  FIG. 4 , the UWB node  2  comprises a second antenna  20 , a second UWB communications module  22  and a micro control unit  24 . The UWB node  2  is connected to the system controller  1  via the micro control unit  24 . The micro control unit  24  is controlled by the system controller  1  to process digital signals. After processing, the micro control unit  24  sends the result to the second UWB communications module  22  connected to the micro control unit  24 . The second UWB communications module  22  then emits an inquiry signal to a remote UWB emitter  3  via the second antenna  20 , and receives a reply signal of the remote UWB emitter  3 , as shown in  FIG. 3 .  
      As shown in  FIG. 5 , the system controller  1  comprises a central control unit  10 , a display unit  16 , a memory unit  12  and an operational unit  14 . The system controller  1  uses the central control unit  10  to connect the UWB nodes  2 , the display unit  16 , the memory unit  12  and the operational unit  14 . A user can send a control signal to the central control unit  10  via the operational unit  14 . After the control signal is processed by the central control unit  10 , it is sent to the UWB nodes  2  to activate the UWB nodes  2  to emit the inquiry signal to a remote UWB emitter  3 . At the same time, the UWB nodes  2  acquire the reply signal output by the UWB emitter  3 .  
      After the UWB nodes acquire the reply signal output by the UWB emitter  3 , the reply signal is sent to the central control unit  10  and then displayed by the display unit  16  after being processed by the central control unit  10 . The reply signal and the location of the UWB node  2  can thus be acquired for the object of searching for people.  
       FIG. 6  is a flowchart of a people-locating method of the present invention, which comprises the following steps. When a user is declared lost, an ID data set on a UWB emitter located on the lost user is acquired (Step S 100 ). A system controller is used to output a control signal to at least a UWB node distributed in a stationary environment (Step S 102 ). The UWB nodes use the UWB wireless transmission technique to perform inquiry search (Step S 104 ). Next, the UWB nodes use the UWB wireless transmission technique to acquire the ID data set on the UWB emitter located on the lost user (Step S 106 ). A location signal of the UWB node distributed in the stationary environment and the searched ID data are sent to the system controller at the same time to reveal the location of the lost user in the stationary environment (Step S 1108 ). Finally, a nearby person is informed to go to the location of the UWB node to search for the lost user (Step S 110 ).  
      Before the above step of acquiring an ID data set on a UWB emitter located on the lost user, it is necessary to dispense the UWB emitters having ID data to users. The system controller is used to register a basic user data of the user. The registration step can be paired with a step of taking a photograph of the user via a digital still camera. When a user is declared lost, the location signal sent by the UWB nodes and the ID data along with the user data make the search easier.  
      Further, when the UWB nodes can&#39;t find the ID data set on the UWB emitter located on the lost user in the stationary environment, the system controller can be used to request a nearby police unit to aid in the search.  
      Moreover, these UWB nodes are connected to a system controller to receive a control signal output by the system controller. After these UWB nodes receive the control signal, the UWB wireless transmission technique is used to perform an inquiry action. These UWB nodes output inquiry signals to at least a UWB emitter located on users to obtain reply signals output by these UWB emitters, respectively. The reply signal is an ID data of the UWB emitter.  
      The system controller can acquire the location of a user in the stationary environment. The location is in the wireless communications range of these UWB nodes. Therefore, if a lost user is to be searched for, the system controller can be used to output the control signal to these UWB nodes distributed in the stationary environment. These UWB nodes will output inquiry signals to obtain a reply signal output by a UWB emitter located on the lost user in the short-distance wireless communications range.  
      After the UWB nodes obtain a reply signal output by the UWB emitter located on the lost user, the reply signal will be sent to the system controller. The system controller will thus acquire the location of the lost user in the short-distance wireless communications range.  
      Although the present invention has been described with reference to the preferred embodiments thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have been suggested in the foregoing description, and others will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims.