Abstract:
A communication apparatus communicates with a radio communication device. The communication apparatus includes a display unit, a controller, a first receiver, a second receiver, and a transmission unit. The controller is configured to switch between a first mode and a second mode, the second mode in which the display unit is not supplied power. The first receiver unit is configured to receive a request message from the radio communication device in the second mode. The second receiver unit is configured to receive a measuring information that is related to a position of the communication apparatus in response to the request message received by the first receiver unit. And the transmission unit is configured to transmit position that is calculated based on the measuring information.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is based upon and claims the benefit of priory from the prior Japanese Paten Application No. 2006-112303 filed April 14 the entire contents of which are incorporated herein by reference. 
       FIELD OF THE INVENTION 
       [0002]    The present invention relates to a communication apparatus, for example a cellular phone, or PDA. 
       BACKGROUND OF THE INVENTION 
       [0003]    In recent years, the progress and spread of cellular phones has been remarkable. The age group of cellular phone users has also been varied, and the cellular phone has become used by users of a wide age range. In order to measure position information on the cellular phone which especially a child or an old person possesses, and thus to measure the position of the child or the old person, it has been required to use other electronic equipment, and there has been technology for enabling the position of the cellular phone which a child or an old person possesses to be known. 
         [0004]    In order to obtain the position information on the cellular phone which a child or an old person possesses, after another cellular phone (for example, mother&#39;s phone) requires the child&#39;s or old person&#39;s cellular phone to provide the position information, the child&#39;s phone or old person&#39;s phone measures a position of the phone, and the phone transmits the position to the mother&#39;s phone. Thereby, the mother was able to know the position of the child or old person. 
         [0005]    However, when the power supply of the cellular phone which a child or an old person possesses is OFF, the mother cannot know the child&#39;s or old person&#39;s position. 
       SUMMARY OF THE INVENTION 
       [0006]    Accordingly one object of the present invention is to provide a communication apparatus which increases the possibility that a position of the communication apparatus can be obtained. 
         [0007]    To achieve the above object, according to one aspect of the present invention communication apparatus for communicating with a radio communication device is provided which includes: a display unit; a controller configured to switch between a first mode, and a second mode in which the display unit is not supplied power; a first receiver unit configured to receive a request message from the radio communication device in the second mode; a second receiver unit configured to receive measuring information that is related to a position of the communication apparatus in response to the request message received by the first receiver unit; and a transmission unit configured to transmit a position information that is calculated based on the measuring information. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    In the accompanying drawings: 
           [0009]      FIG. 1  shows the outline of one form of the position information obtaining system which positions the position of the cellular phone MS 1  in the first embodiment, the second embodiment, or third embodiment; 
           [0010]      FIGS. 2A and 2B  show an external appearance of the cellular phone MS 1  according to an embodiment of the present invention when the cellular phone MS 1  is opened to about 180 degrees; 
           [0011]      FIGS. 3A and 3B  show an external appearance of the cellular phone MS 1  when the cellular phone MS 1  is closed; 
           [0012]      FIGS. 4A and 4B  show an example of a display on the display  5  and an example of an arrangement of keys  6  of the cellular phone MS 1 ; 
           [0013]      FIG. 5  is a block diagram illustrating in a simple manner the configuration of the cellular phone MS 1 ; 
           [0014]      FIG. 6  is a table which shows the electronic power supply states of each component of the cellular phone MS 1  in various power supply modes in the first embodiment; 
           [0015]      FIG. 7  is a flow chart which shows a process for switching between the power supply full off-mode, power supply on-mode, and power supply off-mode of the cellular phone MS 1 ; 
           [0016]      FIG. 8  is a flow chart which shows operation of the position information obtaining system using the cellular phone MS 1  in the first embodiment or the second embodiment; 
           [0017]      FIG. 9  shows an example of an e-mail creation screen in the first embodiment, the second embodiment, or the third embodiment; 
           [0018]      FIG. 10  shows another example of an e-mail creation screen in the first embodiment, the second embodiment, or the third embodiment; 
           [0019]      FIG. 11  is a flow chart of operation of the cellular phone MS 1  when the cellular phone is in the power supply on-mode  201 , or the power supply off-mode  202  in the first embodiment; 
           [0020]      FIG. 12  is a table which shows the electronic power supply states of each component of the cellular phone MS 1  in various power supply modes in the second embodiment; 
           [0021]      FIG. 13  is a flow chart of operation of the cellular phone MS 1  when the cellular phone is in the power supply on-mode  201 , or the second power supply off-mode  204  in the second embodiment; 
           [0022]      FIG. 14  is a table which shows the electronic power supply states of each component of the cellular phone MS 1  in various power supply modes in the third embodiment; and 
           [0023]      FIG. 15  is a flow chart of operation of the position information obtaining system using the cellular phone MS 1  in the third embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     First Embodiment 
       [0024]    A first embodiment in which the present invention is employed in a cellular phone will be explained hereinbelow with reference to the accompanying drawings.  FIG. 1  shows a system in which a first cellular phone or another electronic device requests a second cellular phone to measure its own position and transmit the measured position to the requesting device via a management part. 
         [0025]    In the system shown in  FIG. 1 , the position information of a cellular phone MS 1  can be requested by a cellular phone MS 2  or an electronic device PC. The cellular phone MS 2  may have substantially the same structure as the cellular phone MS 1 . In order to obtain the posirion information on the cellular phone MS 1  according to one aspect of the present invention, the cellular phone MS 2  generates a request for the position information (referred to below as “location request mail”), and the cellular phone MS 2  transmits the location request mail to a management part SV connected to the network NW 2 , via a base station BS 2 , a cellular phone network NW 1 , and the network NW 2 . If the cellular phone MS 2  transmits the location request mail to the management part SV of the position information obtaining system, the management part SV requests the position information from the cellular phone MS 1  via the network NW 2 , the cellular phone network NW 1 , and the base station BS 1 . The cellular phone MS 1  transmits the position to the management part SV of the system via the base station BS 1 , the cellular-phone network NW 1 , and the network NW 2 , and the position information is sent to the cellular phone machine MS 2  from the management part SV via the network NW 2 , the cellular-phone network NW 1 , and the base station BS 2 . 
         [0026]    The electronic device PC obtains the position information of the cellular phone MS 1  in a substantially similar manner. In order to obtain the position information of the cellular phone MS 1 , the electronic device PC generates location request mail and transmits the location request mail to the management part SV of the system via the network NW 2 . If the electronic device PC transmits the location request mail to the management part SV of the system, the management part SV requests the position information from the cellular phone MS 1  via the network NW 2 , the cellular phone network NW 1 , and the base station BS 1 . The cellular phone MS 1  transmits the position information to the management part SV of the system via the base station BS 1 , the cellular phone network NW 1 , and the network NW 2 , and the position information is sent to the electronic device PC via the network NW 2  from the management part SV. 
         [0027]    The structure of the cellular phone MS 1  will be explained with respect to  FIGS. 2 to 5 .  FIG. 2  shows an external appearance of the cellular phone MS 1  when the cellular phone MS 1  opened to about 180 degrees.  FIG. 2A  is a front view of the cellular phone MS 1  and  FIG. 2B  is a side view thereof.  FIG. 3  shows the cellular phone MS 1  in a closed state.  FIG. 3A  is a front view of the cellular phone MS 1  and  FIG. 3B  is a side view thereof.  FIG. 4  shows an example of a display on the display  5  of the cellular phone MS 1  (see  FIG. 4A ) and an example of an arrangement of the keys  6  of the cellular phone MS 1  (see  FIG. 4B ). And  FIG. 5  is a block diagram illustrating an internal configuration of the cellular phone MS 1 . 
         [0028]    The cellular phone MS 1  has an upper case section  2  and a lower case section  4  which is connected to the upper section  2  via a hinge  3 . The upper case section  2  has a display  5  such as an LCD, a speaker  9  for outputting sound (such as a voice), magnetic sensors  11   a,    11   c  for detecting an orientation of the upper case section  2  with respect to the lower case section  4 , a camera  12 , and a sub-display  13  such as an LCD. The sub-display  13  and camera  12  are provided on the same surface of the upper case section  2 . 
         [0029]    The lower case section  4  has digit/letter keys  6  for inputting, e.g., digits, letters or instructions, side keys  7  for conducting operations of the cellular phone MS 1 , a microphone (mouthpiece)  8  for sound collection, and magnetic sensors  11   b,    11   d  for detecting an orientation of upper case section  2  with respect to the lower case section  4 . 
         [0030]    As shown in  FIG. 5 , which illustrates the internal configuration of the cellular phone MS 1 , the cellular phone MS 1  includes a controller  101  for conducting control of the entire cellular phone MS 1 , a microphone controller  108 , a speaker controller  109 , a camera controller  112  for controlling the camera  12 , a memory  115  including a ROM or a NAND memory, a volatile RAM  111  for temporary storage, a first display controller  113  for controlling the display  5 , a second display controller  105  for controlling the sub-display  13 , an operation unit  106  for recognizing that the keys  6 , and side keys  7  have been pushed down, a communication unit  116  for conducting wireless communication control by using an antenna  117 , and a GPS communication unit  118  for conducting wireless communication control by using a GPS antenna  119 . The entire system is controlled by the controller  101 . The controller  101  also controls whether the position of the cellular phone MS 1  is permitted to be obtained by external devices. The controller  101  includes power supply controller  101   a,  which perform power supply control in accordance a power supply mode set by a user (described in greater detail below). 
         [0031]    The memory  115  stores a programs executed by the controller  101  and various information data, and the memory  115  includes a permission member (authorized requester) memory  115   a,  which stores information, such as, for example, an e-mail address and/or a terminal ID. The information stored in the permission member memory  115   a  identifies one or more e-mail addresses and/or one or more terminals, for example, which are permitted to obtain the position information of the cellular phone MS 1 . 
         [0032]    The display controller  105  controls the sub-display  13  and display controls the display data that are instructed by the controller  101  to be outputted. 
         [0033]    The display controller  113  controls the display  5  and display controls the display data that are instructed by the controller  101  to be outputted. 
         [0034]    The communication unit  116  has functions of sending information indicated by the controller  101  by wireless communication via the antenna  117  and receiving information sent by wireless communication via the antenna  117 . 
         [0035]    The GPS communication unit  118  is activated by the controller  101 . The GPS communication unit  118  has a function of transmitting and receiving information through the GPS antenna  119  to determine the location of the cellular phone MS 1 , if a request for obtaining the information to determine the location of the cellular phone MS 1  is received from the controller  101 . 
         [0036]    The camera controller  112  is activated by the controller  101 , and images inputted from the camera  12  are displayed, e.g., on display  5  via the first display controller  113  or on display sub-display  13  via the second display controller  105 . 
         [0037]    The operation unit  106  has a key input unit for recognizing that the keys  6  and side keys  7  have been pushed. The operation unit  106  can recognize that a plurality of kinds of keys including digit keys, letter keys, and functional keys. When a keys  6  or side key  7  is operated by a user, the operation unit  106  conveys a recognition signal corresponding to the operated key to the controller  101 , which starts an operation corresponding to the operated key. 
         [0038]    As shown in  FIG. 4B , the lower case section  4  has the following keys  6 : digit keys  61 , a “*” key  62 , a “#” key  63 , a soft key left  64 , a confirmation key  65 , a soft key right  66 , a cross-like key  67 , a mail key  68 , a browser key  69 , a telephone key  70 , a power source key  71 , and a clear key  72 . In addition to digits, Japanese alphabet KANA symbols, various signs, and English alphabet letters are allocated to the digit keys  61 . For example, the numeral “ 1 ”, Japanese KANA symbols “         ”, “         ”, “         ”, “         ”, “         ” (respectively represented by “a”, “i”, “u”, “e”, and “o” in English alphabet letters), and signs “,”, “@” are allocated to the key “1”. In addition, numeral “2”, Japanese KANA symbols “         ”, “         ”, “         ”, “         ”, “         ” (respectively represented by “ka”, “ki”, “ku”, “ke” and “ko” in English alphabet letters), and alphabet letters “A”, “B”, “C”, “a”, “b”, “c” are allocated to key “2”. Still further, in addition to the asterisk allocated to “*” key  62 , in a letter input state, a symbol list and pictogram list can by called up by the key  62 . Furthermore, in addition to the pound sign allocated to the “#” key  63 , in a letter input state key  63  can be operated to toggle the letter that can be input with the digit keys  61 . 
         [0039]    The cross-like key  67  includes an upper key, a lower key, a left key, a right key, and the confirmation key  65  is provided in the center of the direction keys. The cross-like key  67  can be operated to move the cursor in the up-down and left-right directions. In addition, the confirmation key  65  can be pushed to confirm various functions. The mail key  68  can call up a mail send/receive function. The browser key  69  allows for connection to Web or the like. The telephone key  70  is mainly used when receiving a phone call or when an usual operations of making a phone call. The power source key  71  is mainly used to turn the power source ON and OFF, as well as to complete a function or editing and to erase a letter while a letter(s) is/are being input. Furthermore, if the clear key  72  is pushed in a standby screen, a memo register can be called up. 
         [0040]    As shown in  FIG. 4A , an antenna pictogram  51  showing the present level of sensitivity of the antenna  117 , a battery pictogram  52  showing the present remaining battery charge of the cellular phone MS 1 , and a time display  53  displaying the current time are displayed in the uppermost row (referred to hereinbelow as “upper pictogram row”) of the display  5  of the cellular phone MS 1 . In addition, simple explanations of the functions presently executable by operating the left soft key  64 , the confirmation key  65  and the right soft key  66  are displayed in the lowermost row (referred to hereinbelow as “lower pictogram row”) of the display  5  of the cellular phone MS 1 . More specifically, an explanation corresponding to the left soft key provided by the lower left pictogram  54 , an explanation corresponding to the confirmation key  65  is provided by the central lower pictogram  55 , and an explanation corresponding to the right soft key  66  is provided by the lower right pictogram  56 . For example, in the display shown in  FIG. 4A , if the left soft key  64  is pushed, a “RETURN” function is executed; if the confirmation key  65  is pushed, the function that is presently highlighted/identified (not shown in the figure) can be selected; and if the right soft key  66  is pushed, a “sub-menu” is displayed. 
         [0041]    As described hereinabove, moreover, sensors  11   a  to  11   d  for detecting the orientation of the upper case section  2  with respect to the lower case section  4  are provided in the upper case section  2  and lower case section  4 . The sensors  11   a  to  11   d  comprise, for example, magnetic sensors. For example, when a distance of the sensor  11   a  and the sensor  11   b  are approached within a fixed range, the sensor  11   a  outputs a detection signal. The orientation of the upper case section  2  with respect to the lower case section  4  is detected by the detection signal. Of the sensors  11   a  to  11   d,  a pair of sensors  11   a  and  11   b  detect whether or not the upper case section  2  and lower case section  4  lie one on top of another (are closed/overlapped). And when the upper case section  2  and lower case section  4  lie on top of one another, a pair of sensors  11   c  and  11   d  detect whether the display  5  is inward (for example the state shown in  FIG. 3 ) or the sub-display  13  is inward (the display  5  is outward). 
         [0042]    Next, the position information obtaining system using the cellular phone MS 1  respect to  FIGS. 6 to 11 . The cellular phone MS 1  can be placed in a power supply on-mode  201 , a power supply off-mode  202 , and a power supply full off-mode  203 .  FIG. 6  indicates the elements of the cellular phone MS 1  that are supplied with power in each of the three power supply modes (in  FIG. 6 , a circle designates that power supply is ON, and an “x” designates that power supply is OFF). First, in the power supply on-mode  201 , the controller  101 , the second display controller  105 , the operation unit  106 , the microphone controller  108 , the speaker controller  109 , RAM  111 , the camera controller  112 , the first display controller  113 , the memory  115 , the communication unit  116 , and the GPS communication unit  118  are all in a state in which the power supply thereto is turned on, or in a suspend state in which a power supply ON is possible. 
         [0043]    Second, in the power supply off-mode  202 , at least the controller  101 , RAM  111 , the memory  115 , the communication unit  116 , and the GPS communication unit  118  are in the state in which the power supply thereto is turned on, or in the suspend state in which a power supply ON is possible. In addition, in the power supply off-mode  202 , the other elements of the cellular phone MS 1  are in a state in which the power supply thereto is turned off, except for the typical exception (for example, power source key  71 ). 
         [0044]    Third, in the power full off-mode  203 , the controller  101 , the second display controller  105 , the operation unit  106 , the microphone controller  108 , the speaker controller  109 , RAM  111 , the camera controller  112 , the first display controller  113  the memory  115  the communication unit  116  and the GPS communication unit  118 , are all in the state in which the power supply is turned off. In addition, in the power full off-mode  203 , a RTC (real-time clock, which is not illustrated) and some other elements may be turned on. 
         [0045]    Since more elements are supplied with power in the power supply off-mode  202  than in the power full off-mode  203 , power consumption is less in the power full off-mode  203  than in the power supply off-mode  202 . 
         [0046]    In addition, in the power supply off-mode  202  and the power full off-mode  203 , since the second display controller  105  and first display controller  113  are not supplied with power, the power supply of the display  5  and sub-display  13  also turned off. Moreover, in the power supply off-mode  202 , if a location request mail is received by the cellular phone MS 1  (as will hereinafter be described in detail), the communication unit  116  transmits an ACK signal, which advises the management part SV that the cellular phone MS 1  has received the location request mail. In the power supply off-mode  202 , the controller  101  controls the communication unit  116  such that the communication unit  116  does not transmit a reply signal (for example the ACK signal) if the communication unit  116  receives another signal (for example a signal indicating an ordinary mail or a signal indicating an incoming call). 
         [0047]    Next, transition between the power full off-mode  203 , the power supply off-mode  202 , and the power supply on-mode  201  will be explained with respect to  FIG. 7 , in which the cellular phone MS 1  is initially set in the power full off-mode  203  (Step S 131 ). Next, the controller  101  detects whether an on-shift operation (for example, a power supply “ON” operation such as depression more than a predetermined (fixed time) to shift the cellular phone MS 1  to the power supply on-mode  201  has been made via the operation unit  106  (Step S 132 ). If the controller  101  detects that the on-shift operation has been made (Yes of Step S 132 ), the controller  101  performs control to shift the cellular phone MS 1  to the power supply on-mode  201  (Step S 133 ). On the other hand, if the controller  101  detects that the on-shift operation has not been made via the operation unit  106 , the controller  101  proceeds to Step S 134  (No of Step S 132 ). 
         [0048]    In Step S 134 , the controller  101  detects whether a first off-shift operation (for example, depression of the power source key  71  twice within a fixed time) to shift the cellular phone MS 1  to the power supply off-mode  202  has been made via the operation unit  106  (Step S 134 ). If the controller  101  detects that the first off-shift operation has been made (Yes of Step S 134 ), the controller  101  performs control to shift the cellular phone MS 1  to the power supply off-mode  202  (Step S 135 ). If the controller  101  detects that the first off-shift operation has not been made via the operation unit  106 , the controller  101  returns to Step S 132  (No of Step S 134 ) and the controller  101  again detects whether the on-shift operation has been made. 
         [0049]    Next, in the power supply off-mode  202  of Step S  135 , the controller  101  detects whether the on-shift operation to shift the cellular phone MS 1  to the power supply on-mode  201  (for example, depression of the power source key  71  for more than a fixed time) has been made via the operation unit  106  (Step S 136 ). If the controller  101  detects that the on-shift operation has been made (Yes of Step S 136 ), the controller  101  performs control to shift the cellular phone MS 1  to the power supply on-mode  201  (Step S 133 ). If the controller  101  instead detects that the on-shift operation has not been made via the operation unit  106 , the controller  101  proceed to Step S 137  (No of Step S 136 ). 
         [0050]    Next, in the Step S 137 , the controller  101  detects whether a second off-shift operation (for example, depression of the power source key  71  for more than a fixed time following the entering of a four-digit personal identification number via digit keys  61 ) to shift the cellular phone MS 1  to the power full off-mode  203  has been made by the operation unit  106  (Step S 1   37 ). If the controller  101  detects that the second off-shift operation has been made (Yes of Step S 137 ), the controller  101  performs control to shift the cellular phone MS 1  to the power full off-mode  203  (Step S 138 ). If the controller  101  detects that the second off-shift operation to has not been made via the operation unit  106 , the controller  101  returns to Step S 136  (No of Step S 137 ) and the controller  101  again detects whether the on-shift operation has been made. 
         [0051]    Next, in the power supply on-mode  201  of Step S 133 , the controller  101  detects whether the first off-shift operation to shift the cellular phone MS 1  to the power supply off-mode  202  (for example, depression of the power source key  71  twice within a fixed time) has been made via the operation unit  106  (Step S 139 ). If the controller  101  detects that the first off-shift operation has been made (Yes of Step S 139 ), the controller  101  performs control to shift the cellular phone MS 1  to the power supply off-mode  202  (Step S  135 ). If the controller  101  detects that the first off-shift operation has not been made via the operation unit  106 , the controller  101  proceeds to Step S 140  (No of Step S 139 ). 
         [0052]    In Step S 140 , the controller  101  detects whether the second off-shift operation (for example, depression of the power source key  71  for more than a fixed time following the entering of the four-digit personal identification number via the digit keys  61 ) to shift the cellular phone MS 1  to the power full off-mode  203  has been made via the operation unit  106  (Step S 140 ). If the controller  101  detects that the second off-shift operation has been made (Yes of Step S 140 ), the controller  101  performs control to shift to the cellular phone MS 1  to the power full off-mode  203  (Step S 138 ). If the controller  101  detects that the second off-shift operation has not been made via the operation unit  106 , the controller  101  returns to Step S 139  (No of Step S 140 ) and the controller  101  again detects whether the on-shift operation has been made. 
         [0053]    The on-shift operation, the first off-shift operation, and the second off-shift operation are not limited to the examples described above. It may be desirable for the second off-shift operation to be an operation that is not simple so that it cannot be performed by mistake. Of course, in the power supply on-mode  201 , naturally the usual operations of making a phone call, creating mail, etc. can be performed by the user, but a description of these functions is omitted. 
         [0054]    Next, with reference to  FIG. 8 , operation of the position information positioning system using the cellular phone MS 1  will be explained. First, when the user of a requestor-side terminal device(s) (for example, the cellular phone MS 2 , the electronic device PC, etc) wants to know the location of the cellular phone MS 1 , the requestor-side terminal device creates the location request mail transmits the request mail to the management part SV (Step S 111 ) based on input (e.g. via keys) by the user of the requestor-side terminal device. In addition, in order to make the management part SV recognize the difference between the location request mail and ordinary mail, when the requestor-side terminal device creates the location request mail, it is desirable to distinguish the location request mail by putting in keywords, such as “position demand”, etc., in the subject  211  of the location request mail, as shown in the e-mail creation screen shown in  FIG. 9 . Alternatively, the location request mail may be distinguished from a ordinary mail by providing different keys to initiate transmission of the location request mail and the ordinary mail, as shown in  FIG. 10 . 
         [0055]    More specifically,  FIG. 9  shows one example of an e-mail creation screen. In  FIG. 9  shows that the destination of the e-mail is highlighted. If the cross-like key  67  is operated in a first direction by the user, the first display controller  113  performs control to move a focus toward the first direction. Moreover, if the confirmation key  65  is pressed when an item is highlighted, the first display controller  113  may perform control to display details of the highlighted item (e.g. a guide indication that is displayed at the central lower pictogram  55 ). 
         [0056]      FIG. 10  shows an alternative example of an e-mail creation screen. Explanation is omitted for the portions of  FIG. 10  that are the same as the corresponding portions of  FIG. 9 . 
         [0057]    As shown in  FIG. 10 , transmission of an ordinary mail is initiated by pushing the left soft key  64 . On the other hand, transmission of the location request mail is initiated by pushing the right soft key  66 . In addition, while an e-mail is being created, as shown in  FIG. 10  the first display controller  113  displays a first guide “send” at the lower left pictogram  54  of the display  5 . The controller  101  performs control to transmit the created mail via the communication unit  116  as ordinary mail if the controller  101  detects that the left soft key  64 is pushed while the screen shown in  FIG. 10  is displayed. Moreover, the controller  101  performs control to set a flag to identify the mail as location request mail and performs controls to transmit the created mail via the communication unit  116  as the location request mail, if the controller  101  detects that the right soft key  66  is pushed while the screen shown in  FIG. 10  is displayed. The location request mail can thereby be distinguished from ordinary mail. 
         [0058]    In the e-mail creation screens shown in  FIG. 9  and  FIG. 10 , identification of the location request mail is not limited to entering specific keywords in the subject of the e-mail. The controller  101  may alternatively set a character (or a pictorial symbol and a mark) of the head of the text or at the tail of the text. In addition, in the example shown in  FIG. 10 , the controller  101  need not necessarily set a flag to identify the mail as location request mail. The controller  101  may alternatively attach a preset attached file if the controller  101  detects that the right soft key  66  (initiating transmission of location request mail) is pushed. 
         [0059]    Returning to FIG.  8 ,. in Step S 111 , if the requestor-side terminal device MS 2  (or PC) transmits a mail, the management part SV receives the mail. The management part SV detects whether the received mail is location request mail or ordinary mail (Step S 112 ). More specifically, the management part SV analyzes the received mail, and detects whether the received mail is the location request mail based on, for example, ON/OFF of the flag, or based on the existence of a keyword in the subject of the mail. 
         [0060]    If the management part SV detects that the received mail is the location request mail (Yes of Step S 112 ), the management part SV forwards the location request mail to the cellular phone MS 1  (Step S 113 ). 
         [0061]    If the cellular phone MS 1  is capable of receiving the location request mail, the cellular phone MS 1  receives the location request mail. That is, the cellular phone MS 1  cannot receive the location request mail if the communication unit  116  of the cellular phone MS 1  is not supplied power, so that the communication unit  116  of the cellular phone MS 1  cannot receive the location request mail (for example, in the power full off-mode  203 ). Next, if the cellular phone MS 1  receives the location request mail, the cellular phone MS 1  transmits an ACK signal indicating that demand mail was received, to the management part SV (Step S 114 ). The controller  101  of the cellular phone MS 1  detects whether a mail address of a transmitting agency of the location request mail corresponds with a mail address stored in the permission member memory  115   a  of the memory  115  (Step S 115 ). If the controller  101  detects that the mail address of the transmitting agency does not correspond with any mail address stored in the permission member memory  115   a,  the controller  101  transmits an error report, which is a notice that the cellular phone does not permit to notice a position of the cellular phone MS 1 , to the requestor-side terminal device via the management part SV. 
         [0062]    Moreover, in Step S 11   5 , if the controller  101  detects that the mail address of the transmitting agency corresponds with a mail address stored in the permission member memory  115   a,  the controller  101  shifts to a measuring mode (Step S 116 ) to acquire the position of the cellular phone MS 1 . Then, the communication unit  116  of the cellular phone MS 1  transmits the position information acquired in the measuring mode to the requestor-side terminal device via MS 2  (or PC) the management part SV. The measuring mode is described in more detail later. 
         [0063]    After the management part SV transmits the location request mail in Step S 113 , the management part SV detects whether it has received the ACK signal from the cellular phone MS 1  (Step S 117 ). If the management part SV has received the ACK signal, the management part SV awaits reception of the measuring result from the cellular phone MS 1  (Yes of Step S 117 , to &lt; 1 &gt;). If the management part SV does not receive the ACK signal, the management part SV detects whether a fixed time from transmission of the location request mail in Step S 113  has passed (Step S 118 ). If fixed time has not passed in Step S 118 , the management part SV returns to Step S 117  and again detects whether the management part SV has received the ACK signal from the cellular phone MS 1  (No of Step S 118 ). If the fixed time has passed in Step S 118 , the management part SV transmits a second error report, which is a notice that the cellular phone MS 1  cannot measure the positioning of the cellular phone MS 1 , to the requestor-side terminal device (Yes of Step S 118 , and Step S 119 ). 
         [0064]    Moreover, in Step S 112 , if the management part SV detects that the received mail is not the location request mail (No of Step S 112 ), the management part SV treats the mail as ordinary mail (Step S 120 ). 
         [0065]    Next, the operation of the cellular phone MS 1  in the position information positioning system operating as shown  FIG. 8  will be described with respect to  FIG. 11 , which is a flow chart of operation of the cellular phone MS 1  when the cellular phone MS 1  is in power supply on-mode  201  or in power supply off-mode  202 . As described above, in power supply full off-mode  203 , the cellular phone MS 1  cannot receive the location request mail. 
         [0066]    First, the controller  101  detects whether it has received the location request mail from the management part SV (Step S 141 ). Here, if the controller  101  does not detect that the location request mail is received, the controller  101  to perform Step S 141  (No of Step S 141 ). And if the controller detects that the location request mail has been received in Step S 141 , the controller S 101  controls the communication unit  116  to transmit the ACK signal to the management part SV (Step S 142 ). 
         [0067]    Next, the controller  101  detects whether a mail address of a transmitting agency corresponds with a mail address stored in the permission member memory  115   a  of the memory  115  (Step S 143 ). If the controller  101  detects that the mail address of the transmitting agency does not correspond with any mail address stored in the permission member memory  115   a,  the controller  101  transmits the error report (a notice that the cellular phone MS 1  does not permit to notice a position of the cellular phone MS 1 ) to the requestor-side terminal device (No of Step S 143 , Step S 147 ). 
         [0068]    Moreover, in Step S 143 , if the controller  101  detects that the mail address of the transmitting agency corresponds with a mail address stored in the permission member memory  115   a,  the controller  101  controls the GPS communication unit  118  so as to acquire the measuring information of the cellular phone MS 1  (Step S 144 , positioning mode start). The GPS communication unit  118  acquires measuring information (for example, time information) for acquiring the position information of the cellular phone MS 1  from a satellite. The controller  101  detects whether it received the measuring information from the GPS communication unit  118  (Step S 145 ). If the controller  101  receives the measuring information, the controller  101  calculates the position information of the cellular phone MS 1  based on the received the measuring information. And the controller  101  performs control to transmit the position information to the requestor-side terminal device MS 2  (or PC) (Yes of Step S 145 , Step S 146 , positioning mode end). It is desirable to transmit the position information by adding the position information to a reply mail to the location request mail. Moreover, calculation of positioning information in Step S  146  may be to calculate in the server which is not illustrated, may receive the calculated positioning information, and may transmit to the requestor-side terminal MS 2  after receiving the calculated positioning information. 
       Second Embodiment 
       [0069]    Below, second embodiment of the present invention, as it relates to a cellular phone, will be explained herein below with reference to the accompanying drawings. According to the second embodiment, less elements of the cellular phone are supplied with power in the power supply off-mode than according to the first embodiment. In addition, the composition of the system configuration of the cellular phone MS 1 , the management part SV, and the requestor-side terminal MS 2  (or PC) (as shown in  FIGS. 1-5  and  7 - 10 ) is the same as in the first embodiment, and an explanation thereof is omitted below. 
         [0070]      FIG. 12  shows the power supply state of each component of the cellular phone MS 1  in the second embodiment. According to the second embodiment, the cellular phone MS 1  may be set in the power supply on-mode  201 , the power full off-mode  203 , and a second power supply off-mode  204 . The power supply on-mode  201  and the power supply full off-mode  203  the same in the second embodiment as in the first embodiment. Accordingly, an explanation thereof is omitted. 
         [0071]    In the second power supply off-mode  204 , at least the controller  101 , RAM  111 , the memory  115 , and the communication unit  116  are in the state in which the power supply is turned on, or in a standby state in which a power supply ON is possible, and the other components are in the power supply off state except for the typical exceptions (for example, power source key  71 ). In addition, in the second power supply off-mode  204 , since the second display controller  105  and the first display controller  113  are in the power supply off state, the power supply of the display  5  and the sub-display  13  is also turned off. 
         [0072]    In addition, since more elements are not supplied with power in the second power supply off-mode  204  than in the power supply off-mode  202 , power consumption is less in the second power supply off-mode  204  of the second embodiment than in the power supply off-mode  202  of the first embodiment. According to the second embodiment, shifting between the power supply on-mode  201 , the power supply full off-mode  203 , and the second power supply off-mode  204  is the same as the shifting between modes according to the first embodiment that is explained above with respect to  FIG. 7 , explanation thereof is omitted. 
         [0073]    Next, in the second embodiment, a flow of operation when the cellular phone MS 1  is in the second power supply off-mode  204  will be described with respect to  FIG. 13 . The other flows of operation of the cellular phone MS 1  according to the second embodiment are the same as the flows of operation of the cellular phone MS 1  according to the first embodiment. Accordingly, a explanation thereof is omitted. 
         [0074]    First, the controller  101  detects whether it has received the location request mail from the management part SV (Step S 141 ). Here, if the controller  101  does not detect that it has received the location request mail, the controller  101  continues Step S 141  (No of Step S 141 ). If the controller  101  does detect that it has received the location request mail, the controller  101  performs control such that the communication unit  116  transmits the ACK signal to the management part SV (Step S 142 ). 
         [0075]    Next, the controller  101  detects whether a mail address of a transmitting agency corresponds with a mail address stored in the permission member memory  115   a  of the memory  115  (Step S 143 ). If the controller  101  detects that the mail address of the transmitting agency does not correspond with any mail address stored in the permission member memory  115   a,  the controller  101  transmits the error report (a notice that the cellular phone MS 1  does not permit to notice a position of the cellular phone MS 1 ) to the requestor-side terminal device (No of Step S 143 , Step S 147 ). 
         [0076]    Moreover, in Step S 143 , if the controller  101  detects that the mail address of the transmitting agency corresponds with a mail address stored in the permission member memory  115   a,  the controller  101  performs control to initiate power supply to the GPS communication unit  118  (Step S 148 , positioning mode start). Then, the controller  101  performs control such that the GPS communication unit  118  acquires the measuring information of the cellular phone MS 1  (Step S 144 ). The GPS communication unit  118  acquires the measuring information (for example, time information) for acquiring the position information of the cellular phone MS 1  from a satellite. The controller  101  detects whether it has received the measuring information from the GPS communication unit  118  (Step S 145 ). If the controller  101  receives the measuring information, the controller  101  calculates the position information of the cellular phone MS 1  based on the received the measuring information. And the controller  101  performs control to transmit the position information to the requestor-side terminal device MS 2  (or PC) (Yes of Step S 145 , Step S 146 , positioning mode end). Next, the controller  101  performs control to stop the supply of power to the GPS communication unit  118  (Step S 149 ). 
       Third Embodiment 
       [0077]    Below, a third embodiment of the present invention, as it relates to a cellular phone, will be explained herein below with reference to the accompanying drawings. According to the second embodiment, less elements of the cellular phone are supplied with power in the power supply off-mode than according to the first and second embodiments. In addition, according to the third embodiment the flow of operation of the position information obtaining system differs from the first and second embodiments. According to the third embodiment, the composition of the system configuration of the cellular phone MS 1 , the management part SV, and the requestor-side terminal MS 2  (or PC (as shown in  FIGS. 1-5  and  7 ) is the same as in the first embodiment, and an explanation thereof is omitted below. 
         [0078]      FIG. 14  shows the power supply state of each component of the cellular phone MS 1  in the third embodiment. According to the third embodiment, the cellular phone MS 1  may be set in the power supply on-mode  201 , the power full off-mode  203 , and a third power supply off-mode  205 . The power supply on-mode  201  and the power supply full off-mode  203  is the same in the third embodiment as in the first embodiment. Accordingly, an explanation thereof is omitted. 
         [0079]    In the third power supply off-mode  205 , at least the controller  101 , RAM  111 , and the memory  115  are in the state in which the power supply is turned on, or in a standby state in which a power supply ON is possible, and the other components are in the power supply off state except for the typical exceptions (for example, power source key  71 ). In addition, in the third power supply off-mode  205 , since the second display controller  105  and the first display controller  113  are in the power supply off state, the power supply of the display  5  and the sub-display  13  is also turned off. 
         [0080]    In addition, since more elements are not supplied with power in the third power supply off-mode  205  than in the second power supply off-mode  204 , power consumption is less in the third power supply off-mode  205  of the third embodiment than in the power supply off-mode  204  of the second embodiment. According to the third embodiment, shifting between the power supply on-mode  201 , the power supply full off-mode  203 , and the third power supply off-mode  205 , is the same as the shifting between modes according to the first embodiment that is explained above with respect to  FIG. 7 . Accordingly, explanation thereof is omitted. 
         [0081]    Next, in the third embodiment, a flow of operation when the cellular phone MS 1  is in the third power supply off-mode  205  will be described with respect to  FIG. 15 . 
         [0082]    First, operation of the cellular phone MS 1  will be explained. After the cellular phone MS 1  is set in the third power supply off-mode  205  by the operation shown in  FIG. 7  (Step S 151 ), the controller  101  detects whether a predetermined time has passed since the beginning of Step S 151  (i.e., since setting the cellular phone MS 1  in the third power supply off-mode  205 ) (Step S 152 ). The controller  101  continues Step S 152  until the controller  101  detects that the predetermined time has passed (No of Step S 152 ). In Step S 152 , if the controller  101  detects that the predetermined time has passed, the controller  101  performs control to initiate power supply to the communication unit  116  and the GPS communication unit  118  (Step S 153 ). Then, the controller  101  performs control so as to acquire the measuring information via the GPS communication unit  118 . The GPS communication unit  118  acquires the measuring information from a satellite, and when the controller  101  receives the measuring information, the controller  101  calculates the position information of the cellular phone MS 1  based on the measuring information. The controller  101  transmits the calculated position information to the management part SV via the communication unit  116  (Step S 154 ). Then, the controller  101  performs control to stop the supply of power to the communication unit  116  and the GPS communication unit  118  (Step S 155 ). 
         [0083]    The management part SV receives the position information, associates the received position information with a measured time (or a calculated time or a received time), and stores the received position information and the measured time in a database (not illustrated) (Step S 156 ). 
         [0084]    Next, operation of the requestor-side terminal device MS 2  (or PC) and the management part SV will be explained. The requestor-side terminal MS 2  (or PC) creates the location request mail (or ordinary mail) and transmits the created mail to the management part SV by the same method as described above with respect to the first embodiment (Step S 161 ). If the management part SV receives the mail, the management part SV detects whether the received mail is the location request mail or the ordinary mail (Step S 162 ). The detection performed in Step S 162  is the same as that performed in the first embodiment. If the management part SV detects that the received mail is the location request mail, the management part SV proceeds to Step S 164 . On the other hand, if the management part SV detects that the received mail is the ordinary mail, the management part SV treats the mail as the ordinary mail (Step S 163 ). 
         [0085]    Next, the management section SV detects whether a sender of the received mail is a positioning permission member (i.e., an authorized requester of the position information) (Step S 164 ). The user of the cellular phone MS 1  preliminarily transmits and stores a mail address (or addresses) of that are permitted to receive the position information stored in a memory (not shown) of the management part SV, and the detection of the Step S 164  is executed by comparing the mail address stored in the memory of the management section SV with the mail address of the sender of the location request mail. 
         [0086]    In Step S 164 , if the management part SV detects that the sender of the received mail is not a positioning permission member (No of Step S 164 ), the management part SV transmits a third error report, which is a notice which indicates that the requester side terminal is not permitted to obtain the position information. If the management part SV detects that the sender of the received mail is a positioning permission member (Yes of Step S 164 ), the management part SV proceeds to Step S 165 . 
         [0087]    Next, in Step S 165 , the management part SV detects whether position information from the cellular phone MS 1  is stored in the database of the management part SV (Step S 165 ). If the management part SV detects that position information from the cellular phone MS 1  is not stored in the database of the management part SV, the management part SV transmits a fourth error report, which indicates that the management part SV cannot notify a position result to the requestor-side terminal (No of Step S 165 ). If the management part SV detects position information from the cellular phone MS 1  is stored in the database of the management part SV, the management part SV transmits the newest position information to the requestor-side terminal MS 2  (or PC) along with the time associated with the position information (Yes of Step S 165 ). 
         [0088]    Then, the management part SV transmits the received location request mail to the cellular phone MS 1  by the same routine as the ordinary mail (Step S 166 ).