BEST MODE FOR CARRYING OUT THE INVENTION

[0052] Next, an embodiment of the present invention will be explained. This embodiment shows one aspect of the present invention and does not limit the invention. It can be changed in any way within the scope of the present invention.

[0053] <A-1. Configuration of Embodiment>

[0054] <1. Overall Configuration of Communication System>

[0055] FIG. 1 is a diagram illustrating the overall configuration of a communication system according to the present embodiment. In the figure, a simplified mobile phone 10 is a mobile unit provided in a simplified mobile phone network 12 , such as a PHS. This simplified mobile phone 10 can communicate wirelessly with a base station 11 of the simplified mobile phone network 12 to receive a PHS communication service. Mobile phone 20 is (Personal Digital Cellular) a mobile unit provided in a mobile phone network 22 , such as PDC. Mobile phone 20 can communicate wirelessly with a base station 21 of mobile phone network 22 to receive a PC communication service.

[0056] A mobile phone 30 is a mobile unit provided in a mobile packet communication network 32 . This mobile phone 30 can communicate wirelessly with a base station 31 of a mobile packet communication network 32 to receive a packet communication service. Further, mobile phone 30 has a built-in GPS receiver 34 . This GPS receiver 34 may be used by mobile phone 30 to acquire high precision positional information comprised of a longitude, latitude, and altitude or high precision current time information. Note that mobile phone 30 may also be of a type which does not have a built-in GPS receiver 34 , but can be connected to a GPS receiver 34 .

[0057] A gateway server 40 is provided between simplified mobile phone network 12 , mobile phone network 22 , mobile packet communication network 32 , or other mobile communication network and the Internet 70 ; and relays the transfer of data between networks having different communication protocols. Explaining this more specifically, for example, gateway server 40 converts between the communication protocol for mobile packet communication network 32 and a standard communication protocol of the Internet 70 , that is, the TCP/IP (Transmission Control Protocol/Internet Protocol) or UDP/IP (User Data Protocol/Internet Protocol) to relay the transfer of data between mobile packet communication network 32 and Internet 70 . Note that when mobile units 10 , 20 , and 30 use the TCP/IP, gateway server 40 only converts protocol at a layer lower than the TCP/IP.

[0058] A positional information service server 45 provides a positional information service to terminal 80 , such as PC, connected to the Internet 70 , or IP (Information Provider) server 90 , mobile unit 10 , 20 , or 30 , etc. This positional information service server 45 is provided as a separate apparatus from gateway server 40 . This is so as to disperse the load relating to the positional information service, which has been increasing along with the greater sophistication in functions of positional information services and the increase in the service users, from gateway server 40 and thereby lighten the load on gateway server 40 . Note that in this specification, mobile units 10 , 20 , and 30 , terminal 80 , IP server 90 , and other communication terminals able to receive the provision of the positional information service from positional information service server 45 will be referred to as “service terminals”.

[0059] A measuring center 50 has the function of acquiring and storing the positional information of mobile units 10 , 20 , and 30 . Here, the positional information of mobile units 10 , 20 , and 30 stored in measuring center 50 will be explained. Firstly, in simplified mobile phone network 12 , a base station ID, for identifying the wireless zone of base station 11 in which the simplified mobile phone 10 is currently located for each simplified mobile phone 10 , is registered with a service control station (not shown here).

[0060] Measuring center 50 , for example, accesses the service control station of simplified mobile phone network 12 periodically to acquire the base station IDs of each simplified mobile phone 10 . Further, measuring center 50 , as shown in FIG. 2 , stores the telephone number of each simplified mobile phone 10 , the base station ID acquired, and acquisition date and time information on the base station ID acquired from simplified mobile phone network 12 in base station ID table 50 a linked together. Note that in base station ID table 50 a shown in FIG. 2 , the first four digits of the acquisition date and time information show the month and day, and the last four digits the time.

[0061] Further, in mobile phone network 22 , an area ID, for identifying the service area in which the mobile phone 20 is currently located for every mobile phone 20 , is registered with the service control station (not shown here). Here, the “service area” is an area comprised of the wireless zones of a plurality of base stations 21 . Measuring center 50 for example accesses the service control station of mobile phone network 22 periodically to acquire the area IDs of the mobile phones 20 . Further, measuring center 50 , as shown in FIG. 3 , stores the telephone number of each mobile phone 20 , the area ID acquired, and acquisition date and time information on the area ID acquired from mobile phone network 12 in area ID table 50 b linked together.

[0062] Further, in mobile packet communication network 32 , a sector ID, for identifying the sector of the wireless zone in which mobile phone 30 is currently located for every mobile phone 30 , is registered with the service control station (not shown here). Here, the “sector” is a partial area of a wireless zones divided by a directional antenna of base station 31 . Measuring center 50 for example accesses the service control station of mobile phone network 32 periodically to acquire the sector IDs of mobile phones 30 . Further, measuring center 50 , as shown in FIG. 4 , stores the telephone number of each mobile phone 30 , the sector ID acquired, and acquisition date and time information on the sector ID acquired from the mobile packet communication network 32 in sector ID table 50 c linked together. Note that when the power of mobile phone 30 is not on or mobile phone 30 is located outside of the service area, as shown in FIG. 4 , the symbol “-” indicating that mobile phone 30 is not located in any sector is stored in the “sector ID” field.

[0063] Further, measuring center 50 has a GPS correction unit 50 d . This GPS correction unit 50 d corrects the GPS measured value of a mobile phone 30 measured by the D (Differential)-GPS system based on the GPS measurement error value held by measuring center 50 itself. Further, GPS correction unit 50 d stores the positional information of mobile phone 30 measured in a longitude and latitude table (not shown here) in GPS correction unit 50 d linked with the telephone number of mobile phone 30 etc.

[0064] Note that measuring center 50 may also be configured to store the positional information of mobile units 10 , 20 , and 30 for a predetermined period as log information. In this case, measuring center 50 can also store not just the single latest positional information for each mobile unit 10 , 20 , and 30 , but a plurality of positional information.

[0065] Note that the positional information of mobile units 10 , 20 , and 30 stored in measuring center 50 are of various data formats as described above, such as the base station ID format, area ID format, sector ID format, and GPS format. Further, a service terminal may also have a data format of positional information using the same. For example, there are some service terminals desiring to use positional information in a data format comprised of the longitude, latitude, and altitude, while there are other service terminals desiring to use the positional information in the base station ID format. Further, there are service terminals desiring to use positional information of a data format of the name of the city, village, town, or other administrative division.

[0066] To make up for these differences in data formats and maintain compatibility of the positional information, a positional information conversion apparatus 60 is provided. This positional information conversion apparatus 60 is provided with various conversion tables for converting the data format of positional information to another data format; and can convert the data format of positional information to a data format which can be handled by different service terminals or a data format desired to be used by different service terminals.

[0067] IP server 90 provides content relating to the positional information provided from positional information service server 45 , to terminal 80 or mobile units 10 , 20 , and 30 . Further, terminal 80 or IP server 90 can access positional information service server 45 directly through the Internet 70 .

[0068] <2. Configuration of Mobile Unit>

[0069] FIG. 5 is a block diagram illustrating the configuration of a simplified mobile phone 10 . In the figure, simplified mobile phone 10 has a control unit 10 A, a wireless unit 10 B, and a user interface unit 10 C. These units are connected with each other through a bus 10 D. Control unit 10 A is provided with a CPU, memory, etc, and controls the units of simplified mobile phone 10 . Wireless unit 10 B controls wireless communications executed with base station 11 . User interface unit 10 C is comprised of a microphone, speaker, and audio processing unit for speaking, a control panel for inputting numbers, letters, operating instructions, etc., and a liquid crystal display unit, etc. Note that the configuration of mobile phone 20 is substantially the same as the configuration of simplified mobile phone 10 illustrated in FIG. 5 , so the explanation will be omitted.

[0070] Next, FIG. 6 is a block diagram illustrating the configuration of a mobile phone 30 . In the figure, mobile phone 30 has a control unit 30 A, a wireless unit 30 B, a user interface unit 30 C, and a GPS receiver 34 . The parts are connected with each other through a bus 30 D. Mobile phone 30 differs from mobile phone 20 in the point that packet communication is possible and the point that a GPS receiver 34 is built in. GPS receiver 34 receives signals from a plurality of GPS satellites to measure the current position of the mobile phone 30 or the current time etc. These measurement values are transmitted from wireless unit 30 B, through base station 31 and mobile packet communications network 32 , to measuring center 50 where GPS correction unit 50 d executes D-GPS correction. Further, mobile phone 30 has application software or a browser function for receiving a positional information service.

[0071] <3. Configuration of Positional Information Service Server>

[0072] FIG. 7 is a block diagram illustrating the configuration of positional information service server 45 . In the figure, positional information service server 45 has a communication control unit 451 , a control unit 452 , a subscriber information database 453 , a measuring system database 454 , a positional information registration database 455 , a billing management database 456 , and a verification and authorization database 457 . These units are connected to each other through a bus 458 .

[0073] Communication control unit 451 controls the data communication between the service terminals and measuring center 50 and positional information conversion apparatus 60 . Control unit 452 is provided with a CPU, memory, etc. and controls the units of the positional information service server 45 . Subscriber information database 453 is a database in which the subscriber information of the positional information service is stored. As shown in FIG. 8 , subscriber information database 453 stores the “telephone number” of the service terminal owned by a subscriber, “e-mail address”, and “IP address” for each “subscriber ID” assigned to subscribers of the positional information service. Note that as an IP address, it is possible for example to use an IP address of an IPv4 (Internet Protocol version 4) format or IPv6 format.

[0074] Subscriber information database 453 is referred for identifying the service terminal requesting measurement or to be notified, or mobile unit 10 , 20 , or 30 to be measured. For example, control unit 452 can identify mobile unit 10 , 20 , or 30 to be measured by the “telephone number” or “e-mail address”. Note that subscriber information database 453 shown in FIG. 8 can also be configured to further store personal information (name, address, date of birth, gender, age, etc.) linked with the “subscriber ID”.

[0075] Next, FIG. 9 is a diagram illustrating the data configuration of the measuring system database 454 . As shown in the figure, measuring system database 454 stores all measuring systems able to measure the position of a mobile unit 10 , 20 , or 30 owned by a subscriber for each “subscriber ID”. In the illustrated example, it is provided with the fields “base station ID system”, “area ID system”, “sector ID system”, “A system (GPS)”, “B system (GPS)”, and “C system (GPS)” for each “subscriber ID”. “1” is stored in the fields of the measuring systems which can measure position for each mobile unit 10 , 20 , or 30 , and “0” in the fields of the measuring systems which cannot measure position. Measuring system database 454 is prepared based on the model information of mobile units 10 , 20 , and 30 owned which are reported from the subscribers when subscribing to the positional information service.

[0076] Further, positional information registration database 455 stores positional information registered and indicated by the service terminals and associated information. Here, “associated information” is for example the measuring system or acquisition date and time information of the positional information, information identifying the mobile units 10 , 20 , and 30 to be measured, a comment showing the state of the mobile units 10 , 20 , and 30 at the time of measuring (for example, “moving” or “stopped”), and etc. By providing this positional information registration database 455 in positional information service server 45 , a service terminal need not store the positional information or associated information inside the service terminal, but can refer to the positional information or associated information which was registered there in advance by accessing positional information registration database 455 . Further, if the mobile unit is configured to store its own current positional information and associated information in positional information registration database 455 at predetermined time intervals, a third party can refer to the information without measuring.

[0077] Billing management database 456 stores billing information of the subscribers generated along with use of the positional information service. Control unit 452 calculates the amount of billing for each subscriber in accordance with the amount of access to positional information service server 45 or the measuring system used for acquisition of the positional information, and stores it in billing management database 456 . Here, the amount of access to positional information service server 45 is calculated based on for example the access time or the number of accesses. Further, for acquisition of the positional information, for example, a rate for each use is set for each measuring system. The amount of billing is calculated in accordance with the type of the measuring system used, the number of acquisitions, etc.

[0078] Verification and authorization database 457 stores verification information for determining the correctness of the subscriber or authorization information indicating the content of the service allowed for the subscriber for each subscriber. Positional information service server 45 verifies the user by referring to subscriber information database 453 or verification and authorization database 457 when receiving a request for access from a service terminal. Further, positional information service server 45 determines whether the service request is a service in the range allowed for the subscriber by referring to verification and authorization database 457 when receiving a service request from a service terminal.

[0079] Note that in the following explanation of the operation, to avoid complicating the explanation, the descriptions of the user verification or authorization and charging are omitted. Further, for communication between positional information service server 45 and service terminals, it is possible to apply a SSL (Security Socket Layer) etc. for ensuring security.

[0080] <A-2. Operation of Embodiment>

[0081] Next, the operation of the embodiment will be explained.

[0082] <1. Basic Functions Provided by Positional Information Service>

[0083] The basic functions of the positional information service provided by positional information service server 45 may be roughly divided into a total of six functions, which are, a registration function, reference function, conversion function, notification function, measuring function, and search function.

[0084] <1-1. Registration Function>

[0085] The registration function is a function of registering positional information etc. in positional information registration database 455 in positional information service server 45 . A sequence chart for the case of execution of this registration function is shown in FIG. 10 . Note that in this figure, the “terminal requesting registration” is specifically a mobile unit 10 , 20 , or 30 , terminal 80 , or IP server 90 .

[0086] As shown in the figure, firstly, the terminal requesting the registration transmits a registration request to positional information service server 45 (step S 1 ). This registration request includes an instruction instructing registration, the subscriber ID of the unit requesting the registration, the positional information is to be registered, subscriber information identifying mobile unit 10 , 20 , or 30 for which the positional information has been measured, etc. When receiving the registration request, positional information service server 45 registers the positional information included in the registration request or the subscriber ID of mobile unit 10 , 20 , or 30 for which the positional information is measured etc. in positional information registration database 455 (step S 2 ). Here, the positional information registered in positional information registration database 455 may have added to it (the positional information), the above-mentioned measuring system, or other associated information, such as acquisition date and time information. Further, after registration, positional information service server 45 transmits a registration response indicating that registration of the positional information has been completed to the terminal requesting the registration (step S 3 ).

[0087] <1-2. Reference Function>

[0088] The reference function is a function of referring to the positional information etc. registered in positional information registration database 455 . A sequence chart for the case of execution of this reference function is shown in FIG. 11 . Note that the “terminal requesting reference” in this figure is specifically a mobile unit 10 , 20 , or 30 , a terminal 80 , or an IP server 90 .

[0089] As shown in this figure, firstly, the terminal requesting reference transmits a reference request to positional information service server 45 (step S 11 ). This reference request includes an instruction instructing reference, the subscriber ID of the unit requesting the reference, subscriber information identifying mobile unit 10 , 20 , or 30 to be referred to, a limiting condition, etc. Here, the “limiting condition” is for example information limiting the range of acquisition time of the positional information referred to, information limiting the measuring system, etc.

[0090] When receiving a reference request, positional information service server 45 first searches through subscriber information database 453 , as a key that the subscriber information included in the reference request, and acquires the subscriber ID of mobile unit 10 , 20 , or 30 to be referred to. Next, positional information service server 45 searches through positional information registration database 455 in accordance with this subscriber ID and the limiting condition, and acquires the corresponding positional information (step S 12 ). Next, positional information service server 45 transmits a reference response including the acquired positional information or associated information etc. back to the terminal requesting reference (step S 13 ).

[0091] <1-3. Conversion Function>

[0092] The conversion function is a function of converting the data format of positional information. A sequence chart for the case of execution of this conversion function is shown in FIG. 12 . Note that in this figure, the “terminal requesting conversion” is specifically a mobile unit 10 , 20 , or 30 , a terminal 80 , or an IP server 90 .

[0093] As shown in this figure, firstly, the terminal requesting conversion transmits a conversion request to positional information service server 45 (step S 21 ). This conversion request includes an instruction instructing conversion, the subscriber ID of the unit requesting conversion, information identifying the positional information to be converted, information designating the data formats before conversion and after conversion, etc.

[0094] When receiving a conversion request, positional information service server 45 acquires the positional information to be converted from positional information registration database 455 etc. in accordance with the information designating the positional information to be converted included in the conversion request (step S 22 ). Next, positional information service server 45 transmits the conversion request to positional information conversion apparatus 60 (step S 23 ). This conversion request includes an instruction instructing conversion, the positional information to be converted acquired at the above step S 22 , information designating the data format before conversion and after conversion, etc.

[0095] When receiving the conversion request, positional information conversion apparatus 60 first determines the conversion table used for the conversion processing in accordance with the information designating the data format before conversion and after conversion included in the conversion request. Further, positional information conversion apparatus 60 converts the data format of the positional information using this conversion table (step S 24 ). Next, positional information conversion apparatus 60 transmits the positional information of the converted data format to positional information service server 45 as a conversion response (step S 25 ). When receiving the conversion response from positional information conversion apparatus 60 , positional information service server 45 transmits the positional information included in the conversion response to the terminal requesting the conversion as the conversion response (step S 26 ).

[0096] Note that at step S 21 , the conversion request transmitted from the terminal requesting conversion to positional information service server 45 may also include the positional information to be converted.

[0097] <1-4. Notification Function>

[0098] The notification function is a function for notifying the fact of registration of the positional information in positional information service server 45 , or the positional information to the designated terminal to be notified. A sequence chart for the case of execution of this notification function is shown in FIG. 13 . Note that in the figure, the “terminal requesting notification” and the “terminal to be notified” are specifically mobile units 10 , 20 , or 30 , terminals 80 , or IP servers 90 .

[0099] As shown in the figure, first, the terminal requesting the notification transmits the notification request to positional information service server 45 (step S 31 ). This notification request includes an instruction instructing notification, the subscriber ID of the unit requesting the notification, the subscriber information identifying the terminal to be notified, etc.

[0100] When receiving a notification request, positional information service server 45 searches through subscriber information database 453 , as a key that the subscriber information identifying the terminal to be notified included in the notification request and identifies the terminal to be notified (step S 32 ). Further, positional information service server 45 transmits a notification instruction indicating that the positional information acquired in response to a measuring request has been registered in positional information registration database 455 to the terminal to be notified (step S 33 ). Next, positional information service server 45 transmits a notification response indicating that notification has been completed to the terminal requesting the notification (step S 34 ).

[0101] Note that after step S 32 , positional information service server 45 may also acquire the corresponding positional information registered in the positional information registration database 455 or associated information, include the positional information or associated information in the notification instruction, then transmits the notification instruction to the terminal to be notified.

[0102] Further, notification instruction notified from positional information service server 45 to the terminal to be notified may also include just the associated information such as the registration time of the positional information except the positional information. In this case, at the terminal to be notified, the user identifies the positional information which the user desires to acquire from the registration time and other associated information included in the received notification instruction, and acquires the positional information from positional information service server 45 by using the reference function.

[0103] <1-5. Measuring Function>

[0104] The measuring function is a function for measuring the position of a mobile unit 10 , 20 , or 30 in accordance with a request from a terminal. This measuring function may be roughly divided into a quasi-measuring system for acquiring corresponding positional information from positional information of mobile units 10 , 20 , and 30 stored in measuring center 50 , and an actual measuring system for actually measuring the position of a mobile unit 10 , 20 , or 30 in accordance with a measuring request.

[0105] <1-5-1. Quasi-Measuring System>

[0106] FIG. 14 is a sequence chart of the case of execution of a quasi-measuring system. Note that the sequence chart shown in this figure explains the case of the terminal requesting the measurement transmitting a measuring request for its own position to positional information service server 45 , that is, the case where the terminal requesting measurement is a mobile unit 10 , 20 , or 30 to be measured.

[0107] As shown in the figure, firstly, mobile unit 10 , 20 , or 30 requesting the measurement executes processing for prompting the user to input the measuring quality conditions required to execute the requesting measurement (step S 41 A). Here, the “measuring quality conditions” are desires of the party requesting measurement (user) regarding the quality of the measurement of the positional information. The measuring quality conditions are comprised, for example, of information designating the range of time of measuring, information designating the precision of measuring, information designating a condition relating to the rate of billing accompanying measurement, information designating the allowable waiting time up to acquiring the measuring result, etc.

[0108] Users place various demands on the positional information to be acquired using the positional information service. For example, they want the current positional information, not any other, want positional information of as high a precision as possible, want to acquire positional information at as low a rate as possible even at the expense of a lower precision, want to acquire positional information in as short a time as possible, etc. Mobile unit 10 , 20 , or 30 requesting the measurement displays an input screen as illustrated in FIG. 15 in order to acquire the desires of the user with respect to the positional information. Further, the user inputs measuring quality conditions in accordance with this input screen. For example, in the example shown in FIG. 15 , conditions of items such as the measuring time, measuring precision, rate, and allowable waiting time are set in accordance with control input, and the priority order of these conditions is set in accordance with control input.

[0109] Next, mobile unit 10 , 20 , or 30 requesting the measurement transmits the measuring request to positional information service server 45 (step S 41 B). This measuring request includes an instruction instructing measurement, the subscriber ID of the unit requesting the measurement (subscriber ID identifying mobile unit 10 , 20 , or 30 to be measured), the measuring quality conditions input at step S 41 A, etc.

[0110] When receiving a measuring request, positional information service server 45 searches through subscriber information database 453 , as a key that the subscriber ID of mobile unit 10 , 20 , or 30 to be measured included in the measuring request, and acquires the telephone number of mobile unit 10 , 20 , or 30 to be measured (step S 42 ). Next, positional information service server 45 refers to measuring system database 454 , and identifies all of the measuring systems able to measure the position of mobile unit 10 , 20 , or 30 which to be measured (step S 43 ).

[0111] Next, positional information service server 45 selects the measuring system most suitable for the measuring quality conditions received at step S 41 B from the identified measuring systems (step S 44 ). When there is just one measuring system identified at step S 43 , however, that single identified measuring system is selected regardless of the content of the measuring quality conditions.

[0112] For example, in the measuring quality conditions illustrated in FIG. 15 , it is learned that the user desires to acquire positional information of as high a precision as possible. Consider the case where such measuring quality conditions are transmitted to positional information service server 45 , the mobile unit to be measured is a mobile phone 30 with a built-in GPS receiver 34 , and the position can be measured by the sector ID system and GPS system. In this case, positional information service server 45 selects the GPS system as the measuring system most suitable for the measuring quality conditions among the sector ID system and GPS system at step S 44 .

[0113] Next, positional information service server 45 transmits a measuring response including information relating to the measuring system selected at step S 44 back to mobile unit 10 , 20 , or 30 requesting the measurement (step S 45 ). Due to this, the user can confirm the measuring system used at mobile unit 10 , 20 , or 30 requesting the measurement. Next, mobile unit 10 , 20 , or 30 requesting the measurement transmits a measuring start instruction instructing the start of the measuring to positional information service server 45 (step S 46 ). When receiving the measuring start instruction, the positional information service server 45 transmits a measuring start instruction including the telephone number of mobile unit 10 , 20 , or 30 to be measured identified at step S 42 and the measuring system selected at step S 44 etc., to measuring center 50 (step S 47 ). Note that this sequence chart shows the quasi-measuring system. Therefore, when the measuring system selected at step S 44 is the actual measuring system by GPS, processing relating to measurement is executed in accordance with the sequence chart of the later-mentioned actual measuring system (see FIG. 16 ).

[0114] When receiving the measuring start instruction from positional information service server 45 , measuring center 50 searches, and acquires the positional information of corresponding mobile unit 10 , 20 , or 30 from base station ID table 50 a , area ID table 50 b , sector ID table 50 c , etc. in accordance with the telephone number and measuring system included in the measuring start instruction (step S 48 ). Next, measuring center 50 includes the acquired positional information in a measuring end notification, then transmits it back to positional information service server 45 (step S 49 ). Here, the measuring end notification transmitted back to positional information service server 45 includes not only the positional information, but also the acquisition date and time information of the positional information etc. Positional information service server 45 transmits the measuring end notification including the positional information, acquisition date and time information, etc. received from measuring center 50 , to mobile unit 10 , 20 , or 30 requesting the measurement (step S 50 ). Due to this, mobile unit 10 , 20 , or 30 requesting the measurement can acquire the positional information of its own unit 10 , 20 , or 30 suitable for the desires of the user.

[0115] Even when however acquiring positional information of the base station ID system or area ID system or sector ID system, when “current” is designated as a condition for the measuring time on the input screen illustrated in FIG. 15 or when the limit of range of the measuring time is extremely close to the current time, it is necessary to acquire the positional information of mobile unit 10 , 20 , or 30 to be measured from simplified mobile phone network 12 , mobile phone network 22 , mobile packet communication network 32 , or other mobile communication network in accordance with the measuring request. In this case, at step S 48 , measuring center 50 transmits the telephone number of the mobile unit to the service control station of network 12 , 22 , or 32 providing the mobile unit to be measured to cause the service control station to notify the current positional information of the mobile unit to the measuring center 50 . Next, measuring center 50 includes the thus acquired positional information in a measuring end notification, then transmits it to positional information service server 45 .

[0116] Note that as clear from the above explanation, in the present specification, “measuring” includes searching for, and acquiring corresponding positional information from positional information already acquired and stored in measuring center 50 .

[0117] <1-5-2. Actual Measuring System>

[0118] FIG. 16 is a sequence chart of the case of execution of an actual measuring system by GPS. Note that the sequence chart illustrated explains the case where the terminal requesting measurement transmits a measuring request for its own position to positional information service server 45 , that is, the case where the terminal requesting measuring is mobile unit 10 , 20 , or 30 which to be measured.

[0119] In the figure, the processing from steps S 51 A to S 56 is similar to the processing from steps S 41 A to S 46 of the sequence chart of the quasi-measuring system shown in FIG. 14 , so explanations thereof will be omitted.

[0120] At step S 57 , positional information service server 45 transmits a measuring start instruction including the telephone number of mobile unit 10 , 20 , or 30 to be measured, the selected measuring system, etc. to measuring center 50 (step S 57 ). Due to this, measuring center 50 and mobile unit 10 , 20 , or 30 which to be measured, measure the position by GPS in accordance with measuring protocol determined in advance together (step S 58 ). At this time, positional information service server 45 only relays the data communication executed between measuring center 50 and mobile unit 10 , 20 , or 30 to be measured.

[0121] When the measurement by GPS is completed, measuring center 50 includes the acquired positional information in a measuring end notification, then transmits it back to positional information service server 45 (step S 59 ). Next, positional information service server 45 transmits back the received positional information (including acquisition date and time information), as the measuring end notification, to mobile unit 10 , 20 , or 30 requesting the measurement (step S 60 ).

[0122] Note that measuring center 50 measuring a position by GPS in cooperation with mobile unit 10 , 20 , or 30 to be measured, may be a GPS measuring center which a business offering a GPS measuring service operates independently, separated from the business operating positional information service server 45 . In this case, at step S 57 , positional information service server 45 transmits a measuring start notification including the telephone number of mobile unit 10 , 20 , or 30 to be measured, the measuring system, etc., to the GPS measuring center. Due to this, the GPS measuring center and mobile unit 10 , 20 , or 30 to be measured, measure the position by GPS in accordance with a measuring protocol determined in advance together. The acquired positional information is transmitted from the GPS measuring center to mobile unit 10 , 20 , or 30 requesting the measurement through positional information service server 45 .

[0123] <1-6. Search Function>

[0124] The search function is a function for acquiring the positional information of mobile unit 10 , 20 , or 30 in accordance with a search request from a third party, and transmitting the positional information to the designated terminal to be notified. A sequence chart for the case of execution of this search function is shown in FIG. 17 . Note that in the figure, the “terminal requesting search” and the “terminal to be notified” specifically are mobile units 10 , 20 , or 30 , terminals 80 , or IP servers 90 . Further, the “terminal to be searched”, is a mobile unit 10 , 20 , or 30 . Further, the illustrated example shows the case where the terminal requesting the search, and the terminal to be notified are different. However, the terminal requesting the search, and the terminal to be notified may also be the same terminal. Further, the terminal to be searched may also be the terminal to be notified.

[0125] As shown in the figure, firstly, the terminal requesting the search executes processing for prompting the user to input the measuring quality conditions necessary for the search request (step S 61 A). At this time, the terminal requesting the search displays an input screen similar to that illustrated in FIG. 15 , and the party requesting the search (user) inputs the measuring quality conditions etc. in accordance with the input screen. Here, at the time of requesting the search, as the measuring quality conditions, the measuring time, measuring precision, rate, allowable waiting time, and other conditions, and the priority order of these conditions are input. Further, in addition to the measuring quality conditions, subscriber information identifying mobile unit 10 , 20 , or 30 which to be searched or the terminal to be notified is input.

[0126] Next, the terminal requesting the search transmits a search request to positional information service server 45 (step S 61 B). This search request includes an instruction instructing a search, the subscriber ID of the unit requesting the search, subscriber information identifying mobile unit 10 , 20 , or 30 to be searched, subscriber information identifying the terminal to be notified, the measuring quality conditions input at step S 61 A, etc.

[0127] When receiving the search request, positional information service server 45 transmits a search response indicating that receipt of the search request back to the terminal requesting the search (step S 62 ). Next, positional information service server 45 searches through subscriber information database 453 , as a key that the subscriber information identifying mobile unit 10 , 20 , or 30 to be searched included in the received search request, and acquires the telephone number of mobile unit 10 , 20 , or 30 to be searched (step S 63 ). Next, positional information service server 45 transmits a search instruction to mobile unit 10 , 20 , or 30 to be searched (step S 64 ). By receiving the search instruction, the user of the mobile unit 10 , 20 , or 30 which to be searched can confirm that its own position is being searched for by a third party.

[0128] When the user authorizes the search by the third party, mobile unit 10 , 20 , or 30 to be searched transmits a measuring request to positional information service server 45 (step S 65 ). In response to this, positional information service server 45 first refers to measuring system database 454 , and identifies all of the measuring systems able to measure position of mobile unit 10 , 20 , or 30 to be searched (step S 66 ). Next, positional information service server 45 selects the measuring system most suitable for the measuring quality conditions received from the terminal requesting the search among the identified measuring systems (step S 67 ).

[0129] Next, positional information service server 45 transmits a measuring response including information relating to the selected measuring system back, to mobile unit 10 , 20 , or 30 to be searched (step S 68 ). Due to the receipt of the measuring response, the user of mobile unit 10 , 20 , or 30 to be searched, can confirm the measuring system of positional information of its own unit acquired by the third party. Further, when the measuring system is authorized by the user, mobile unit 10 , 20 , or 30 to be searched transmits a measuring start instruction back to positional information service server 45 (step S 69 ). Note that at step S 68 , positional information service server 45 may be configured to transmit a measuring response including information relating to the selected measuring system to the terminal requesting the search as well. According to this configuration, the user of the terminal requesting the search can also confirm the measuring system used.

[0130] When receiving a measuring start instruction from mobile unit 10 , 20 , or 30 to be searched, positional information service server 45 transmits a measuring start instruction including the telephone number of mobile unit 10 , 20 , or 30 to be searched, and the selected measuring system etc., to measuring center 50 (step S 70 ). In response to this, measuring center 50 acquires the positional information of mobile unit 10 , 20 , or 30 to be searched by the quasi-measuring system, or actual measuring system in accordance with the designated measuring system (step S 71 ). When the measuring is completed, measuring center 50 includes the acquired positional information in a measuring end notification, and transmits it back to positional information service server 45 (step S 72 ). Next, positional information service server 45 transmits the measuring end notification to mobile unit 10 , 20 , or 30 to be searched (step S 73 ).

[0131] Next, mobile unit 10 , 20 , or 30 to be searched, transmits a registration request to positional information service server 45 (step S 74 ). When receiving the registration request, positional-information service server 45 registers the positional information, and the subscriber ID of mobile unit 10 , 20 , or 30 to be searched, etc included in the registration request, in positional information registration database 455 (step S 75 ). Next, positional information service server 45 transmits a registration response back to mobile unit 10 , 20 , or 30 to be searched (step S 76 ).

[0132] Next, the positional information service server 45 searches through subscriber information database 453 , and identifies the terminal to be notified, as a key that the subscriber information identifying the terminal to be notified received at step S 61 B. Next, positional information service server 45 includes the acquired positional information, associated information, etc. in a notification instruction, then transmits it to the terminal to be notified (step S 77 ).

[0133] Note that positional information service server 45 may be configured so that, after receiving the measuring end notification from measuring center 50 at step S 72 , it immediately registers the positional information of mobile unit 10 , 20 , or 30 to be searched, the subscriber ID of mobile unit 10 , 20 , or 30 , etc. included in the measuring end notification, in positional information registration database 455 , transmits the measuring end notification to mobile unit 10 , 20 , or 30 to be searched, and transmits the notification instruction to the terminal to the notified.

[0134] Further, after step S 77 , positional information service server 45 may transmit a notification completion instruction indicating that the notification has been completed, to the terminal requesting the search. Further, in the sequence chart of the search function, positional information service server 45 was configured to register the acquired positional information in positional information registration database 455 . Positional information service server 45 , however, may also transmit the acquired positional information to the terminal to be notified without registration in positional information registration database 455 .

[0135] <2. Application to Information Provision Services>

[0136] When applying the positional information service to the various information provision services using positional information, if dividing the mode of application to the information provision services by function of the positional information service, a total of four modes can be considered, which are, a self position search function, a self position registration function, a third party position registration function, and a third party position search function. Below, an example of the operation for these functions will be explained.

[0137] <2-1. Self Position Search Function>

[0138] As a mode of application of the self position registration function, for example, the mode of use of the positional information of a mobile unit 10 , 20 , or 30 acquired by the positional information service may be considered at a map portal site or general WWW (World Wide Web) site etc. A sequence chart illustrating the operation of the devices in the information provision service using this self position search function is shown in FIG. 18 . Note that in this figure, the user terminal is specifically a mobile unit 10 , 20 , or 30 .

[0139] As shown in the figure, first, the user terminal transmits a service request to an IP server 90 offering this information provision service (step S 101 ). In response to this, IP server 90 sets the measuring quality conditions of the positional information suitable for use in the information provision service, and information designating the data format, etc. (step S 102 A). Next, IP server 90 transmits a service response including the set measuring quality conditions, information designating the data format, etc., to the user terminal (step S 102 B).

[0140] When receiving a service response from IP server 90 , the user terminal includes the measuring quality conditions, information designating the data format, etc. included in the service response, in a measuring request, then transmits it to the positional information service server 45 (step S 103 ). However, the measuring quality conditions etc. may also be confirmed for checking content or changed by the user.

[0141] Next, the processing from step S 104 to step S 109 is the processing for positional information service server 45 acquiring the positional information of the user terminal in accordance with a measuring request from the user terminal, and notifying the acquired positional information to the user terminal. The processing from steps S 104 to S 109 is shown simplified in FIG. 18 , but is similar to the processing from steps S 43 to 50 of the sequence chart of the quasi-measuring system shown in FIG. 14 , so the explanation is omitted.

[0142] When receiving a measuring end notification from positional information service server 45 (step S 109 ), the user terminal includes positional information of its own unit included in the measuring end notification, in a content request, then transmits it to IP server 90 (step S 110 ). In response to this, IP server 90 acquires the content in accordance with the position shown by the positional information of the user terminal and transmits the content as a content response to the user terminal (step S 111 ). In this way, in an information provision service utilizing a self position search function, IP server 90 can set measuring quality conditions suitable for use in the information provision service, information designating the data format, etc. for positional information of its own unit acquired at the user terminal.

[0143] Note that in the sequence chart shown in FIG. 18 , after step S 108 , positional information service server 45 may be configured to execute processing for registering the positional information of the user terminal acquired