Patent Publication Number: US-6993346-B2

Title: Information receiving apparatus and information providing apparatus that communicates information corresponding to location of the information receiving apparatus

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a technique of transmitting information between information processing devices such as computers. In particular, the invention relates to an information transmission technique using a portable information terminal device receiving information transmitted from a plurality of transmission devices. 
   2. Description of the Background Art 
   A system for transmitting geographic information to a mobile terminal device is one example of systems for communicating information between computers. As this type of system, there is a system for transmitting geographic information from a computer which stores geographical database to a mobile terminal device. Japanese Patent Laying-Open No. 6-120877 discloses a navigation system for transmitting navigation information based on position information of a mobile terminal device. 
   Referring to  FIG. 1 , this navigation system includes a center computer  700  generating voice guidance according to destination information received from a radio mobile station  500  via a radio base station  400 , radio base stations  400 ,  410  and  420  connected to center computer  700  via a public circuit  600  and communicating by radio with radio mobile station  500  located in respective management zones  402 ,  412  and  422 , and radio mobile station  500 . 
   Radio mobile station  500  includes a circuit to be used by a travelling person for entering destination information, a circuit for transmitting the entered destination information to center computer  700  via radio base station  400 , and a circuit for outputting voice guidance received from radio base stations  400 ,  410  and  412 . 
   Center computer  700  includes: a geographical database; a voice guidance generating circuit connected to the geographical database and public circuit  600  for generating a first voice guidance for providing a route from a present position  404  to a way point  406  according to the destination information received from radio base station  400  that manages zone  402  including the present position  404 , the present position of radio mobile station  500  recognized from position information of radio base station  400 , and the geographical database; and a transmission circuit connected to the voice guidance generating circuit for transmitting the generated first voice guidance to radio mobile station  500  via radio base station  400 . Center computer  700  further includes an in-zone signal reception circuit receiving from radio base station  410  that manages zone  412  including way point  406  a signal (in-zone signal) indicating presence of radio mobile station  500  in the zone including way point  406 . 
   The voice guidance generating circuit includes a circuit for generating a second voice guidance giving a route from way point  406  to destination  408 . The transmission circuit includes a circuit for transmitting the generated second voice guidance to radio mobile station  500  via radio base station  410 . 
   According to this navigation system, radio mobile station  500  transmits destination information to center computer  700  via radio base station  400 . The voice guidance generating circuit of center computer  700  generates, according to the destination information received from radio base station  400  and position information of radio base stations  400  and  410 , the first voice guidance supplying a route from present position  404  to way point  406 . The voice guide generating circuit of center computer  700  further generates the second voice guidance supplying a route from way station  406  to destination  408 . The transmission circuit of center computer  700  transmits the generated first voice guidance and second voice guidance to radio mobile station  500  via radio base stations  400  and  410 , respectively. The in-zone signal reception circuit of center computer  700  receives the in-zone signal of radio mobile station  500  from radio base station  410  that manages zone  412  including way point  406 . 
   In this way, in accordance with the destination information and other information received via radio base station  400 , the first voice guidance indicating a route from present position  404  to way point  406  is transmitted from center computer  700  to radio mobile station  500 . The first voice guidance is output from radio mobile station  500 . A user carrying radio mobile station  500  follows the first voice guidance and accordingly moves to zone  412  managed by radio base station  410 . In accordance with the in-zone signal and the like of radio mobile station  500  received via radio base station  410 , the second voice guidance indicating a route from way point  406  to destination  408  is transmitted to radio mobile station  500 . Radio mobile station  500  outputs the second voice guide. A travel route  430  from present position  404  to way point  406  and further to destination  408  can consequently be provided from center computer  700  to radio mobile station  500  by means of the voice guidance. The navigation system thus provided enables the user to reach destination  408  even in an unfamiliar area. 
   However, since the voice guidance of this navigation system that is transmitted via radio base stations  400 ,  410  and  420  from center computer  700  to radio mobile station  500  is based on the geographical database of center computer  700  connected via public line  600 , the voice guidance provides details to the same extent. In other words, even if radio mobile station  500  is approaching destination  408 , more detailed information regarding surroundings of destination  408  for example is not provided. 
   SUMMARY OF THE INVENTION 
   One object of the present invention is to provide an information receiving apparatus and an information providing apparatus, employed in a system for receiving data by the information receiving apparatus from a plurality of information providing apparatuses, so as to enable information to be output that is adapted for a location where this information is received. 
   Another object of the present invention is to provide an information receiving apparatus and an information providing apparatus to enable information to be output that is adapted for a location where this information is received and is required by a user. 
   Still another object of the present invention is to provide an information receiving apparatus and an information providing apparatus to enable information to be output depending on value of the information, the information being adapted for a place where the information is received and required by a user. 
   Still another object of the present invention is to provide an information receiving apparatus in which a user can select necessary information. 
   A further object of the present invention is to provide an information receiving apparatus and an information providing apparatus to enable local information to be output that is adapted for a location where this information is received. 
   A still further object of the present invention is to provide an information receiving apparatus and an information providing apparatus to enable information to be output that relates to information required by a user. 
   An information receiving apparatus according to one aspect of the present invention receives information from a plurality of information providing apparatuses. The information receiving apparatus includes: an identification data storage circuit storing information identification data for identifying information to be selected; a reception circuit receiving a plurality of information items from an arbitrary one of the information providing apparatuses; a storage circuit connected to the reception circuit for storing the information items received by the reception circuit; and an output circuit connected to the identification data storage circuit and the storage circuit for selecting and outputting an information item having a predetermined relation with the information identification data stored in the identification data storage circuit. 
   The identification data storage circuit stores information identification data for identifying information designated by a user. The reception circuit receives a plurality of information items from an arbitrary one of the information providing apparatuses. The storage circuit stores the information items received by the reception circuit. The output circuit selects and outputs an information item having a predetermined relation with the information identification data stored in the identification data storage circuit from the information items stored in the storage circuit. 
   Accordingly, the information receiving apparatus receives information items that are identified by the same information identification data but different from each other depending on the information providing apparatuses. For example, when the information identification data is information which specifies a local area, an information providing apparatus located closer to the area specified by the information identification data stores more detailed information regarding that area. Then, the information receiving apparatus can be provided that receives and displays information designated by a user that is of a greater particularity as the apparatus approaches a specific area. 
   Preferably, the information item contains relevant information identification data for identifying information relevant to information contained in the information item and includes priority of the relevant information. The output circuit includes a circuit that selects an information item containing relevant information identification data identical to the information identification data stored in the identification data storage circuit from the information items stored in the storage circuit and then outputs the selected information item according to priority of the selected information item. 
   The information receiving apparatus can display relevant information associated with information designated by the user in the order starting from information with higher priority. 
   Still preferably, the information receiving apparatus includes an input circuit connected to the identification data storage circuit for entering information identification data of information to be selected. 
   The user can enter by means of the input circuit information identification data for identifying desired information to be displayed. 
   Still preferably, the information item further contains relevant information identification data for identifying information relevant to information contained in the information item. The output circuit includes a circuit for selecting and outputting an information item containing either information identification data or relevant information identification data matching the information identification data stored in the identification data storage circuit from the information items stored in the storage circuit. 
   The information receiving apparatus can thus display information associated with relevant information relating to information designated by the user. 
   According to another aspect of the invention, an information receiving apparatus receives information from a plurality of information providing apparatuses. The information receiving apparatus includes an identification data storage circuit storing information identification data for identifying information to be selected, an identification data transmission circuit connected to the identification data storage circuit for transmitting the information identification data stored in the identification data storage circuit to an arbitrary one of the information providing apparatuses, a reception circuit receiving a selected information item transmitted from the arbitrary one of the information providing apparatuses in response to the information identification data transmitted by the identification data transmission circuit, a storage circuit connected to the reception circuit for storing the information item received by the reception circuit, and an output circuit connected to the storage circuit for outputting the information item stored in the storage circuit. 
   The identification data storage circuit stores information identification data for identifying information designated by a user. The identification data transmission circuit transmits the information identification data to the information providing apparatus. The information providing apparatus selects an information item having a predetermined relation with the information identification data stored in the identification data storage circuit and then transmits the selected information item to the information receiving apparatus. The reception circuit receives from the information providing apparatus the information item corresponding to the information identification data. The storage circuit stores the information item received by the reception circuit. The output circuit outputs the information item stored in the storage circuit. 
   Accordingly, the information receiving apparatus receives information items that are identified by the same information identification data but different from each other depending on information providing apparatuses. For example, when the information identification data is information which specifies a local area, an information providing apparatus located closer to the area specified by the information identification data stores more detailed information regarding that area. Then, the information receiving apparatus can be provided that receives and displays information designated by a user that is of a greater particularity as the apparatus approaches a specific area. 
   According to still another aspect of the present invention, an information providing apparatus is employed in an information providing system including an information receiving apparatus and a plurality of information providing apparatuses transmitting information to the information receiving apparatus. The information providing apparatus includes an information storage circuit storing a plurality of information items. The information items each contain information and information identification data for identifying the information. The information identification data is common to the information providing apparatuses. The information contained in the information items differs depending on information identification data and information providing apparatuses. The information providing apparatus further includes a reception circuit receiving information identification data from the information receiving apparatus, an identification data storage circuit connected to the reception circuit for storing the received information identification data, and a transmission circuit connected to the information storage circuit and the identification data storage circuit for selecting an information item having a predetermined relation with the identification data stored in the identification data storage circuit from the information items stored in the information storage circuit and then transmitting the selected information item to the information receiving apparatus. 
   The reception circuit receives information identification data for identifying information designated by a user from the information receiving apparatus. The identification data storage circuit stores the received information identification data. The transmission circuit selects an information item having a predetermined relation with the information identification data stored in the identification data storage circuit and then transmits the selected information item to the information receiving apparatus. The information receiving apparatus outputs the information item transmitted from the information providing apparatus. 
   Accordingly, the information providing apparatus stores information items that are identified by the same information identification data but different from each other depending on information providing apparatuses. For example, when the information identification data is information which specifies any local area, an information providing apparatus located closer to the area specified by the information identification data stores more detailed information regarding that area. Then, the information providing apparatus can be provided that transmits information to the information receiving apparatus to allow the receiving apparatus to display the information being designated by a user that is of a greater particularity as the receiving apparatus approaches a specific area. 
   The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a navigation system of a related art. 
       FIG. 2  schematically shows an information providing system according to the present invention. 
       FIGS. 3A-3D  briefly show information supplied by the information providing system of the invention. 
       FIG. 4  is a control block diagram of an information providing device and a receiving terminal device according to a first embodiment of the invention. 
       FIGS. 5A-5E  and  FIGS. 6A-6C  show information structures according to the first embodiment of the invention. 
       FIG. 7  illustrates priority of relevant information according to the first embodiment. 
       FIGS. 8A and 8B  are flow charts showing a process procedure of an information providing method according to the first embodiment. 
       FIG. 9  shows an information structure in an output data storage unit according to the first embodiment. 
       FIGS. 10A-10C  and  FIGS. 11A-11C  show exemplary pictures displayed by the information receiving device according to the first embodiment. 
       FIG. 12  is a control block diagram of an information providing device and a receiving terminal device according to a second embodiment. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Embodiments of the present invention are hereinafter described in conjunction with the drawings. The following description refers to the same components by the same reference character. These components have the same designation and function and detailed description thereof is not repeated as required. 
   First Embodiment 
   Referring to  FIG. 2 , an information providing system according to one embodiment of the present invention includes a portable receiving terminal device  100  and information providing devices  200  and  300  transmitting information to receiving terminal device  100 . 
   Referring to  FIGS. 3A-3D , a relation between an entire structure of this information providing system and contents of information is briefly described. As shown in  FIG. 3A , a user at home who lives in Tokyo inputs information ID (identification) “10010” representing “Horyuji Temple” for example into receiving terminal device  100 . This user then moves to Tokyo Station carrying receiving terminal device  100 . When receiving terminal device  100  enters an area  202  where information items can be received from information providing device  200  placed at Tokyo Station, receiving terminal device  100  receives an information item. As shown in  FIG. 3B , the information item corresponding to information ID “10010” is displayed on receiving terminal device  100 . In accordance with the information item shown in  FIG. 3B , the user travels to Nara Station carrying receiving terminal device  100 . When receiving terminal device  100  enters an area  302  where information items can be received from information providing device  300  placed at Nara Station, receiving terminal device  100  receives an information item. The information item corresponding to information ID “10010” is displayed on receiving terminal device  100  as shown in FIG.  3 C. 
   Information providing devices  200  and  300  are managed respectively by managing agents  204  and  304  that can get real-time information regarding respective areas where information providing devices  200  and  300  are located. For example, managing agent  304  that manages information providing device  300  acquires information which is difficult to know in real time outside the region near the area specified by information ID data (e.g. traffic jam caused by any car accident which occurred in the area of information providing device  300 ), and accordingly enters this information into information providing device  300  which it manages. Then, information contents supplied from respective information providing devices  200  and  300  are at the different levels of the particularities depending on the relation between the area specified by the information ID data and respective locations of information providing devices  200  and  300 . Further, information contents vary in real time in the region closer to the specified area. 
   The description below relates to a case where the user carrying receiving terminal device  100  rides on a bullet train and then leaves the train at Shin Osaka Station instead of Kyoto Station without following the instruction as shown in FIG.  3 B. When receiving terminal device  100  enters an area where information can be received from an information providing device placed at Shin Osaka Station, receiving terminal device  100  receives information corresponding to information ID “10010” that is displayed as shown in FIG.  3 D. The information providing device located at Shin Osaka Station is managed by a managing agent different from managing agents  204  and  304  mentioned above. Therefore, contents displayed on receiving terminal device  100  include a route from the location (Shin Osaka Station) to Horyuji Temple as well as information at the present time (real-time information associated with the route from Shin Osaka Station to Horyuji Temple), instead of the route from Tokyo Station to Horyuji Temple via Shin Osaka Station, for example. In this way, information is appropriately displayed to enable the user to easily arrive at the destination even if the user deviates from the firstly displayed route. 
   This information providing system is now described in detail. It is noted the information providing system may include a plurality of information providing devices  200  and  300  as discussed in conjunction with FIGS.  2  and  3 A- 3 D; however, they have the same structure and thus information providing device  200  is hereinafter explained as a representative. 
   Referring to  FIG. 4 , the information providing system according to the first embodiment includes receiving terminal device  100  and information providing device  200 . 
   Receiving terminal device  100  includes an input/output unit  110  connected to information providing device  200  for receiving an information item formed of information ID, information, relevant information ID and priority, a storage unit  120  connected to input/output unit  110  for storing the information item received from information providing device  200 , and a retrieval/extraction unit  140  for retrieval of a received information item based on information ID. 
   Receiving terminal device  100  further includes a processor (not shown) for controlling input/output unit  110 , storage unit  120  and retrieval/extraction unit  140 . The processor includes a CPU (Central Processing Unit), an ROM (Read Only Memory) for recording programs executed by the CPU and various data, and an RAM (Random Access Memory) for storing intermediate data in processing executed by the CPU (these components are not shown). 
   Input/output unit  110  includes a reception unit  112  for receiving an information item from a transmission unit  210  in an arbitrary one of a plurality of information providing devices  200 , an input unit  114  such as numerical keypad for entering information ID, and an output unit  116  for displaying information received from information providing device  200 . 
   Reception unit  112  may be connected to information providing device  200  by means of radio communication or by means of wired communication. Radio communication is employed in the first embodiment. In this case, when receiving terminal device  100  enters into an area where radio waves from information providing device  200  reach, reception unit  112  receives an information item from information providing device  200 . 
   Input unit  114  is a keyboard including a numerical keypad and the like for inputting information ID. The information ID is represented by numerals, alphabets, a combination thereof or proper name itself such as “Horyuji Temple.” Output unit  116  outputs information selected from information items received from information providing device  200  by means of characters or voice. 
   The information ID includes, in addition to that entered by input unit  114  as described above, an information ID selected from those preliminarily stored in an ID storage unit  124  of receiving terminal device  100 . For example, an information ID indicating “lavatory” for example which is frequently retrieved and is not proper noun can be selected by input unit  114  without input thereof by input unit  114 . 
   Storage unit  120  includes a received data storage unit  122  connected to reception unit  112  for storing an information item (information ID, information, relevant information ID and priority) received from information providing device  200 , ID storage unit  124  connected to input unit  114  for storing information ID and the like entered by input unit  114 , and an output data storage unit  126  connected to output unit  116  for storing data to be output. 
   Retrieval/extraction unit  140  includes a retrieval unit  142  connected to received data storage unit  122 , ID storage unit  124  and output data storage unit  126  for retrieving, from received information items, an information item having an information ID stored in ID storage unit  124 , and a relevant information ID extraction unit  144  connected to ID storage unit  124  and retrieval unit  142  for extracting a relevant information ID contained in the information item retrieved by retrieval unit  142 . 
   Retrieval unit  142  retrieves, from information items stored in received data storage unit  122 , an information item including an information ID matching an information ID input by input unit  114  and stored by ID storage unit  124 . The retrieved information item (information ID, information, relevant information ID and priority) is transmitted to output data storage unit  126  and to relevant information ID extraction unit  144 . Relevant information ID extraction unit  144  extracts the relevant information ID included in the information item retrieved by retrieval unit  142 . The retrieved relevant information ID is transmitted to ID storage unit  124 . Information ID storage unit  124  stores the information ID input by input unit  114  as well as the relevant information ID included in the information item retrieved by using that information ID. Retrieval unit  142  retrieves an information item including information ID that matches the input information ID and relevant information ID included in the information item retrieved by using that information ID. 
   Information providing device  200  includes a data storage unit  220  for storing an information item formed of information ID, information, relevant information ID and priority, transmission unit  210  connected to data storage unit  220  and receiving terminal device  100  for transmitting the information item stored in data storage unit  220  to receiving terminal device  100 , and a control unit for controlling data storage unit  220  and transmission unit  210 . 
   Referring to  FIG. 5A , an information item includes an information ID and data which is uniquely determined by the information ID in information providing device  200 . Referring to  FIG. 5B , an information item may include a relevant information ID in addition to the information ID and data. For example, the information item shown in  FIG. 5A  includes only the information ID indicating “Horyuji Temple” and no relevant information ID. The information item shown in  FIG. 5B  includes the relevant information ID of information relating to “Horyuji Temple.” Then, when retrieval unit  142  retrieves any information item received, according to the information ID indicating “Horyuji Temple,” an information item having the information ID indicating “Horyuji Temple ” as information ID ( FIG. 5A ) and an information item having the information ID indicating “Horyuji Temple” as relevant information ID ( FIG. 5B ) are retrieved. 
   Referring to  FIG. 5C , description below relates to an information item including the information ID indicating “Horyuji Temple” and further including a relevant information ID indicating “Chuguji Temple.” When retrieval unit  142  retrieves the information item shown in  FIG. 5C , the relevant information ID indicating “Chuguji Temple” included in that information item is stored in ID storage unit  124 . Accordingly, an information item including an information ID or a relevant information ID that matches the information ID indicating “Horyuji Temple” or the information ID indicating “Chuguji Temple” is retrieved. As a result, when the information item shown in  FIG. 5C  is retrieved, the information item shown in  FIG. 5D  including an information ID matching the information ID indicating “Chuguji Temple” and the information item shown in  FIG. 5E  including a relevant information ID matching the relevant information ID indicating “Chuguji Temple” are retrieved. In this way, retrieval unit  142  retrieves not only the information item having the information ID indicating “Horyuji Temple” but also information items relating to the information ID indicating “Horyuji Temple.” 
   Referring to  FIGS. 6A-6C , priority is explained. As discussed above, retrieval unit  142  can retrieve an information item including an information ID stored in ID storage unit  124  as well as an information item including a relevant information ID. Accordingly, various relevant information items can be retrieved, in addition to an information item including an information ID which is entered by input unit  114  at first, such as information items containing relevant information and information items containing information relating to that relevant information. The retrieved information items are stored in output storage unit  126 . A large number of information items stored in output data storage unit  126  include information items containing data highly relevant to the input information ID entered at first and information items containing data less relevant thereto. In this case, an information item having a higher priority is output in precedence to other items to output unit  116 . When retrieval unit  142  retrieves any information item stored in received data storage unit  122  according to the information ID indicating “Horyuji Temple,” resultant information items retrieved include respective information IDs “bus route C,” “bus route D” and “bus route E” as shown in  FIGS. 6A-6C . The retrieved information items each include a relevant information ID and data representing priority of the relevant information. The priority indicates the degree of relevance with respect to the information ID indicating “Horyuji Temple.” 
   Referring to  FIG. 7 , bus route C connects a bus station at Nara Station and the bus station Horyuji Front. Bus route C is the most convenient route to reach Horyuji Temple as the bus station Horyuji Front is closest to Horyuji Temple. Bus route D connects the bus station at Nara Station and the bus station Horyuji East. Bus route D is less convenient to visit Horyuji Temple as the bus station Horyuji East is remote from Horyuji Temple compared with Horyuji Front station. Bus route E connects the bus station City Hall Front which is twenty minutes&#39; walk from Nara Station instead of the bus station at Nara Station, and the bus station Horyuji Front. Bus route E is inconvenient to visit Horyuji Temple. In this case, first, second and third priorities are assigned, respectively, to bus route C, bus route D and bus route E as priorities of respective information items relevant to Horyuji Temple. As shown in  FIGS. 6A-6C , information items include data indicating these priorities. 
   Referring to  FIGS. 8A and 8B , receiving terminal device  100  of the information providing system executes a program having a control structure as described below. It is noted that information providing device  200  transmits, when receiving terminal device  100  is detected that is present in an area where transmission from transmission unit  210  is possible, an information item (information ID, information, relevant information ID, and priority) to that detected receiving terminal device  100  by means of radio. 
   In step  100  (“step” is hereinafter abbreviated as “S”), the CPU of receiving terminal device  100  decides whether an information ID is entered by input unit  114 . When the information ID is entered (YES in S 100 ), the process proceeds to S 102 . If no information ID is entered (NO in S 100 ), the process returns to S 100  and waits for input of any information ID. The information ID is entered by selecting it from those stored in advance in ID storage unit  124 . 
   In S 102 , the CPU stores the information ID entered in S 100 . 
   In S 104 , the CPU decides whether or not an information item is received from information providing device  200 . This decision is made by judging whether an information item is received from information providing device  200  via reception unit  112  of receiving terminal device  100 . As described above, when receiving terminal device  100  enters an area where radio communication is possible from transmission unit  210  of information providing device  200 , reception unit  112  receives an information item transmitted from transmission unit  210 . When reception unit  112  receives an information item (YES in S 104 ), the process proceeds to S 106 . When no information item is received by reception unit  112  (NO in S 104 ), the process returns to S 104  to wait for any information item supplied from information providing device  200 . 
   In S 106 , the CPU stores the information item received in S 104  in received data storage unit  122 . The information item stored at this time includes information ID, information, relevant information ID and priority. 
   In S 108 , the CPU decides whether the first information item stored in received data storage unit  122  in S 106  contains an information ID that matches the information ID stored in ID storage unit  124  in S 102 . If the information item includes an information ID matching the stored information ID (YES in S 108 ), the process proceeds to S 110 . Otherwise (NO in S 108 ), the process proceeds to S 112 . In S 110 , the CPU stores the information item retrieved in S 108  in output data storage unit  126 . 
   In S 112 , the CPU decides whether or not the first information item stored in received data storage unit  122  in S 106  includes a relevant information ID that matches the information ID stored in ID storage unit  124  in S 102 . If the information item includes a relevant information ID matching the stored information ID (YES in S 112 ), the process proceeds to S 114 . Otherwise (NO in S 112 ), the process proceeds to S 124 . In S 114 , the CPU stores the information item extracted in S 110  in output data storage unit  126 . 
   In S 116 , the CPU decides whether there is any data indicating priority of the relevant information ID. As shown in  FIGS. 6A-6C , if data indicating priority is included (YES in S 116 ), the process proceeds to S 118 . If there is no data indicating priority as shown in  FIGS. 5A-5E  (NO in S 116 ), the process proceeds to S 120 . 
   In S 118 , the CPU stores in output data storage unit  126  the relevant information ID and its priority as a link destination of the information ID retrieved in S 108 . Referring to  FIG. 9 , with respect to the information ID indicating “Horyuji Temple,” output data storage unit  126  stores the relevant information ID indicating “bus route C” having the first priority as a first link, the relevant information ID indicating “bus route D” having the second priority as a second link, and the relevant information ID indicating “bus route E” having the third priority as a third link. 
   In S 120 , the CPU stores in output data storage unit  126 , the relevant information ID as a link destination of the information ID retrieved in S 108 . The CPU gives instructions to retrieval unit  142  to carry out the steps from S 108  to S 120 . 
   In S 122 , the CPU additionally stores the relevant information ID retrieved in S 112  in ID storage unit  124 . The CPU gives instructions to relevant information ID extraction unit  144  to perform this step. 
   In S 124 , the CPU decides if the retrieval is completed for all information items in received data storage unit  122 . If not (NO in S 124 ), the process returns to S 108  to execute the steps S 108 -S 122  for a next information item. If the extraction for the information items is completed (YES in S 124 ), the process proceeds to S 126 . 
   In S 126 , the information item stored in output data storage unit  126  is displayed by the CPU on a display monitor or the like that corresponds to output unit  116 . The process thereafter proceeds to S 128 . 
   In S 128 , the CPU decides if the entire process is terminated or not. This decision is made by judging whether or not a process termination command is input by input unit  114 . If no process termination command is entered (NO in S 128 ), the process returns to S 104  and receiving terminal device  100  moves to wait for any information item supplied from another information providing device  200  that is different from the information providing device discussed above. When the process termination command is entered (YES in S 128 ), this process is terminated. 
   An operation of the information providing system in accordance with the structure and flowchart heretofore discussed is described. This operation is applied to a user carrying receiving terminal device  100  who travels from the user&#39;s home in a Tokyo suburb to Horyuji Temple. 
   As shown in  FIGS. 2 and 3A , the user enters at home the information ID indicating the destination of travel, “Horyuji Temple,” from input unit  114  of receiving terminal device  100  (YES in S 100 ). The entered information ID is stored (S 102 ). 
   The user of receiving terminal device  100  takes along receiving terminal device  100  to travel from the user&#39;s home to Tokyo Station. When the user arrives at Tokyo Station, transmission unit  210  of information providing device  200  placed at Tokyo Station transmits an information item and reception unit  112  of receiving terminal device  100  receives that information item (YES in S 104 ). The received information item is stored in received data storage unit  122  (S 106 ). An information item is retrieved from stored information items that includes an information ID matching the information ID stored in ID storage unit  124  (S 108 ), and the retrieved one is stored in output data storage unit  126 . The information item stored in output data storage unit  126  is displayed as shown in  FIG. 3B  on a display monitor or the like as output unit  116 . 
   An information item containing an information ID identical to the information ID stored in ID storage unit  124  is retrieved. If the information item like that shown in  FIG. 5C  or  FIG. 5D  is stored in received data storage unit  122 , pictures as shown in  FIGS. 10A-10C  are presented on a display monitor or the like as the output unit. As shown in  FIG. 10A , “Horyuji Temple” corresponding to the information ID entered from input unit  114  is displayed. When a command to proceed to the next information or a next-page command is entered by input unit  114 , detailed information about “Horyuji Temple” as shown in  FIG. 10B  or information about “Chuguji Temple” relevant to “Horyuji Temple” as shown in  FIG. 10C  is displayed. 
   When the user carrying receiving terminal device  100  travels from Tokyo Station to reach Nara Station, reception unit  112  of receiving terminal device  100  receives an information item sent from transmission unit  210  of information providing device  200  placed at Nara Station (NO in S 128 , YES in S 104 ). As discussed above, an information item containing an information ID identical to the information ID stored in ID storage unit  124  is retrieved from received information items (S 108 ), and the retrieved one is stored in output data storage unit  126 . The information item stored in output data storage unit  126  is displayed on a display monitor or the like as the output unit as shown in FIG.  3 C. 
   An information item including an information ID identical to the information ID stored in ID storage unit  124  is retrieved. If information items like those shown in  FIGS. 6A-6C  are stored in received data storage unit  122 , indications as shown in  FIGS. 11A-11C  are presented on a display monitor or the like as the output unit. As shown in  FIG. 11A , “Horyuji Temple” corresponding to the information ID entered from input unit  114  is displayed. Input of a command to proceed to the next information or a next-page command by input unit  114  causes presentation of information about “Horyuji Temple,” a list of relevant information and priority as shown in FIG.  11 B. “Bus route C” with the first priority is selected by input unit  114  and then information about “bus route C” having the first priority among bus routes relating to “Horyuji Temple” is displayed as shown in  FIG. 11C  (S 108 ). 
   The information providing devices placed respectively at Tokyo Station and Nara Station have the same structure. However, data storage unit  220  of the information providing device placed at Nara Station closer to Horyuji Temple stores more detailed information about Horyuji Temple. This means that the user can be provided with more detailed information about the destination as the user approaches that destination. Managing agent  204  of information providing device  200  located at Tokyo Station has difficulty in acquiring the positional relation between Nara Station and the bus stop at Horyuji Temple as well as the priority of bus routes according to the positional relation. On the other hand, managing agent  304  of information providing device  300  located at Nara Station closer to the destination, Horyuji Temple, can readily obtain such detailed information. The managing agents thus hold respective information details to different degrees and accordingly more particular information can be supplied to the user as the user approaches the destination. In other words, depending on the distance between a location where an information providing device is placed and a location specified by an information ID, information of an appropriate particularity can be provided to an information receiving device. Such information having proper details is achieved by designating in advance locations of information providing devices and allowing the information providing devices to hold information of respective levels of particularities different from each other. Specifically, an information providing device located closer to any place regarding an information item specified by an information ID stores information of a greater particularity about that information item. 
   As heretofore discussed, in the information providing system according to the first embodiment, when an information receiving device receives an information item from an information providing device which is closer to an area specified by an information ID, the receiving device can output local information of a greater particularity regarding the area specified by the information ID. It is thus possible to provide an information providing system for supplying data from a plurality of information providing devices to an information receiving device that enables the information receiving device to output information adapted for an area where the receiving device receives that information. 
   Second Embodiment 
   The second embodiment is now described. Details of the hardware structure and process flow chart that are not explained below are identical to those of the first embodiment and description thereof is not repeated where appropriate. 
   In an information providing system according to the second embodiment, the retrieval operation performed by the receiving terminal device in the first embodiment is done by the information providing device. 
   Referring to  FIG. 12 , the information providing system according to the second embodiment includes a portable receiving terminal device  150  and an information providing device  250  transmitting information to receiving terminal device  150 . 
   Receiving terminal device  150  includes an input/output unit  160  connected to information providing device  250  for receiving an information item containing information ID and information, and a storage unit  180  connected to input/output unit  160  for storing the information item received from information providing device  250 . Receiving terminal device  150  further includes a processor (not shown) for controlling input/output unit  160  and storage unit  180 . The processor includes a CPU, an ROM for recording programs executed by the CPU and various data, and an RAM for storing intermediate data in processing executed by the CPU (these components are not shown). 
   Information providing device  250  includes a data storage unit  252  for storing an information item formed of an information ID and information, a retrieval ID reception unit  256  for receiving an information ID from input/output unit  160  of receiving terminal device  150 , a retrieval unit  254  connected to data storage unit  252  and retrieval ID reception unit  256  for retrieving an information item stored in data storage unit  252  according to the received information ID, a transmission data storage unit  262  connected to retrieval unit  254  for storing an information item to be transmitted to receiving terminal device  150 , and a transmission unit  260  connected to transmission data storage unit  262  for transmitting the retrieved information item to receiving terminal device  150 . Information providing device  250  further includes a control unit for controlling data storage unit  252 , retrieval unit  254 , retrieval ID reception unit  256 , transmission unit  260  and transmission data storage unit  262 . 
   Data storage unit  252 , retrieval unit  254  and transmission unit  260  correspond respectively to data storage unit  220 , retrieval unit  142  and transmission unit  210  of the first embodiment and respective structures of components corresponding to each other are the same. Then, detailed description thereof is not repeated where appropriate. 
   Retrieval ID reception unit  256  receives, from an ID transmission unit  164  of receiving terminal device  150  described later, an information ID entered by receiving terminal device  150 . The received information ID is transmitted to retrieval unit  254 . Transmission data storage unit  262  has a function of transferring a retrieved information item to transmission unit  260  in addition to the function of output data storage unit  126  of the first embodiment. 
   Input/output unit  160  includes an input unit  162  such as numerical keypad for entering an information ID, ID transmission unit  164  connected to an ID storage unit  182  of storage unit  180  discussed later for transmitting the information ID entered by input unit  162  to information providing device  250 , a reception unit  168  receiving information supplied from information providing device  250 , and an output unit  170  displaying a received information item. Input unit  162  and output unit  170  correspond respectively to input unit  114  and input unit  116  of the first embodiment and respective structures of components corresponding to each other are the same. Then, detailed description thereof is not repeated where appropriate. 
   Connection of ID transmission unit  164  and reception unit  168  with information providing device  250  may be implemented by radio communication or wired communication. According to the second embodiment, radio communication is employed. In this case, when receiving terminal device  150  enters into an area where radio waves from information providing device  250  reach, ID transmission unit  164  of receiving terminal device  150  transmits an information ID to information providing device  250 . Reception unit  168  of receiving terminal device  150  receives from information providing device  250  an information item (information ID, information) retrieved by using the transmitted information ID. 
   Storage unit  180  includes a received data storage unit  184  connected to reception unit  168  and output unit  170  for storing the information item (information ID, information) received from information providing device  250 , and an ID storage unit  182  connected to input unit  162  and ID transmission unit  164  for storing the information ID entered by input unit  162 . ID storage unit  182  and received data storage unit  184  correspond respectively to ID storage unit  124  and output data storage unit  126  of the first embodiment and corresponding components have the same structure. Then, detailed description thereof is not repeated where appropriate. 
   A program executed by the receiving terminal device  150  and the information providing device  250  in such an information providing system differs from that illustrated by the flowchart of the first embodiment in terms of the following steps. 
   After the process in S 100  and S 102 , the CPU of receiving terminal device  150  transmits the information ID stored in information ID storage unit  180  to information providing device  250  placed in an area where radio communication is possible. 
   The control unit of information providing device  250  transmits the information ID from receiving terminal device  150  that is received by the retrieval ID reception unit  256  to retrieval unit  254 . The control unit retrieves by retrieval unit  254  an information item including an information ID identical to the received information ID from information items stored in data storage unit  252 . The retrieved information item is stored in transmission data storage unit  262 . When the retrieval is completed for all information items stored in data storage unit  252 , the control unit transmits by transmission unit  260  the information item stored in transmission data storage unit  262  to receiving terminal device  150 . 
   The CPU of receiving terminal device  150  receives by reception unit  168  the information item retrieved by retrieval unit  254  of information providing device  250 , and then stores the received information item in received data storage unit  184 . The information item stored in received data storage unit  184  is output to a display monitor or the like corresponding to output unit  170 . 
   An operation of the information providing system in accordance with the structure and flowchart as described above is explained. The operation discussed here applies to a user carrying receiving terminal device  150  who travels from the user&#39;s home in a Tokyo suburb to Horyuji Temple. Similarly to the first embodiment, depending on the distance between a location where an information providing device is placed and a location specified by an information ID, information providing devices hold respective information contents different in particularity levels from each other. 
   As shown in  FIGS. 2 and 3A , the user enters at home the information ID indicating the destination of travel, “Horyuji Temple,” from input unit  114  of receiving terminal device  150  (YES in S 100 ). The entered information ID is stored in information ID storage unit  182  (S 102 ). 
   The user of receiving terminal device  150  takes along receiving terminal device  150  to travel from the user&#39;s home to Tokyo Station. When the user arrives at Tokyo Station, receiving terminal device  150  detects the presence of information providing device  250  placed at Tokyo Station and then transmits the information ID from ID transmission unit  164  to retrieval ID reception unit  256  of information providing device  250 . Information providing device  250  retrieves from information items stored in data storage unit  252  an information item containing an information ID that matches the information ID received by retrieval ID reception unit  256 . The retrieved information item is stored in transmission data storage unit  262 . The information item stored in transmission data storage unit  262  is transmitted from transmission unit  260  to reception unit  168  of receiving terminal device  150 . Receiving terminal device  150  stores the information item received by reception unit  168  in received data storage unit  184 . Receiving terminal device  150  displays the information item on a display monitor or the like which is output unit  170  as shown in FIG.  3 B. 
   When the user carrying receiving terminal device  150  travels from Tokyo Station to arrive at Nara Station, receiving terminal device  150  detects the presence of information providing device  250  placed at Nara Station to transmit the information ID from ID transmission unit  164  to retrieval ID reception unit  256  of information providing device  250 . As described above, information providing device  250  retrieves an information item containing an information ID matching the information ID received by the retrieval ID reception unit  256 . The retrieved information item is stored in transmission data storage unit  262 . The information item stored in transmission data storage unit  262  is supplied from transmission unit  260  to reception unit  168  of receiving terminal device  150 . Receiving terminal device  150  stores the information item received by reception unit  168  in received data storage unit  184 . This information item is displayed by receiving terminal device  150  as shown in  FIG. 3C  on a display monitor or the like corresponding to output unit  170 . 
   Receiving terminal device  150  of the information providing system according to the second embodiment requires no data storage unit  184  of a great memory capacity and a retrieval unit for retrieving an information item according to an information ID. Accordingly, the size of the receiving terminal device can be reduced, which enhances portability. 
   As heretofore discussed, in the information providing system according to the second embodiment, the information receiving device transmits an information ID to an information providing device located closer to an area specified by the information ID. The information receiving device then receives a retrieved information item that provides more detailed local information regarding an area specified by the information ID. Accordingly, it is possible to provide an information providing system for transmitting data to an information receiving device from a plurality of information providing devices that enables the information receiving device to output information adapted for a location where the receiving device receives that information. 
   Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims.