GB2400525A - Mobile telephone system capable of effectively utilizing GPS information even if direct reception by a mobile telephone apparatus is difficult - Google Patents

Abstract

In a mobile telephone system including a mobile telephone base station (20) connected to a telephone network (40) and a mobile telephone apparatus (10) which includes a first GPS unit for receiving a GPS wave as a first received GPS signal to obtain position data of the mobile telephone apparatus by information processing with reference to the first received GPS signal and a radio section for transmitting, by radio communication, the position data of the mobile telephone apparatus to the mobile telephone base station to make the mobile telephone base station inform the telephone network of the position data of the mobile telephone apparatus, the mobile telephone base station includes a mobile telephone base section for transmitting, by radio communication, position information of the mobile telephone base station to the mobile telephone apparatus to enable the mobile telephone apparatus to use the position information of the mobile telephone base station instead of the position data of the mobile telephone apparatus. Preferably, the mobile telephone base station includes a second GPS unit. Alternatively the mobile telephone may receive position information from an external GPS unit 11 mounted in a vehicle, when direct reception is unsuccessful.

Description

MOBILE TELEPHONE SYSTEM AND APPARATUS CAPABLE OF

EFFECTIVELY UTILIZING GPS INFORMATION EVEN IF DIRECT

RECEPTION BY A MOBILE TELEPHONE APPARATUS IS DIFFICULT

Background of the Invention

This invention relates to a mobile telephone system and to mobile telephone apparatus.

In particular, this invention relates to a mobile telephone system in which a mobile telephone apparatus comprises not only a radio section mainly serving as a mobile telephone set adapted to carry out radio communication but also a to GPS unit adapted to receive GPS (Global Positioning System) information so that position data of the mobile telephone apparatus itself is acquired by information processing of the GPS information and reported, via radio communication to a mobile telephone base station, to a telephone network connected to the base station and, in particular, to a mobile telephone system which has a backup function in the case where the mobile telephone apparatus is used in an environment such that the GPS unit thereof can not appropriately receive the GPS information and which achieves low power consumption and saving of memory capacity in the mobile telephone apparatus.

Recently, in the field of mobile telephone communication, it has been proposed to use in a mobile telephone system a GPS unit capable of receiving GPS information transmitted from a GPS satellite and including time information, position information, and map information. This arises from a demand for applications in the case where the user of a mobile telephone apparatus sends an emergency report via radio communication, and another party involved in communication desires to identify the user's position, or in the case where another party searches for the position of the possessor of the mobile telephone apparatus. In addition, there is also a demand for an application such that the user of a mobile telephone apparatus desires to acquire map information of his or her neighbourhood.

As a known technique using the GPS unit in the field of mobile telephone communication, proposals have been made for a structure in which a mobile telephone base station comprises a GPS unit as in a radio telephone controller with GPS as disclosed in Japanese Unexamined Patent Publication (JP-A) No. H06-213998, and for another structure in which a mobile telephone comprises a GPS unit as disclosed in Japanese Unexamined Patent Publication (JP-A) No. H11-18159 and in Japanese Unexamined Patent Publication (JP-A) No. H09-281212.

Generally, a mobile telephone apparatus containing a GPS unit is not always used in a place where the GPS information from the GPS satellite can be received in good condition but is often used in an unreceivable place, typically, an underground mall. In addition, in an automobile where the mobile telephone apparatus is frequently used, the GPS information is often impossible to receive.

Jo In the mobile telephone systems utilizing a GPS unit described above, countermeasures are taken to prepare for the circumstance where the GPS unit contained in the mobile telephone apparatus can not directly receive the GPS information in a good condition. Specifically, in JP-A-H11-18159 the position appears to be extrapolated from the last measurement in dependence upon the speed of the portable telephone set, and in JP-A-H09281212 the last known position is transmitted together with the time at which it was made.

Nevertheless, if the reception state of the GPS information by the GPS unit contained in the mobile telephone apparatus is poor, it is still difficult to effectively utilize the GPS information.

As other prior art, there is Japanese Unexamined Patent Publication (JP-A) No. H10-136537 (equivalent United States Patent No. 6,061,561 was published after the priority date of the present application). This describes a cellular communication system in which for emergency location purposes a base station transmits the location of the base station to a mobile, which then appends it to an emergency call (Fig. 7). The mobile includes a GPS receiver which is used to determine the distance from the base station, so as to control the mobile transmitter power and timing (Figs. 1 and 9). The GPS receiver can also be interrogated by the base station and its location information appended to the emergency call (Fig. 8).

so Finally, United States Patent 5,604,765 to Bruno et al. describes a cellular telephone system which includes low-power RF radio signposts which transmit their locations. In accordance with the invention of that patent, the combined signal strength of the navigation signals is controlled to be at least a predetermined energy level below the energy level of the cellular communication signals. A mobile in the system is equipped with a GPS receiver (Fig. 9), and in regions where there are no RF navigation signals such as from the RF radio signposts, the terminal will fall back to using the GPS receiver to determine its position. It can transmit this position via a control channel or assigned channel of the communications system. A base station in the system also includes a GPS receiver (Fig. 7), which extracts location and accurate timing information which it transmits so that the accurate GPS clock is used as a common time base for all of the base stations.

As with the other prior art, neither of these documents addresses or to provides any solution to the problem where the GPS unit contained in the mobile telephone apparatus cannot receive the GPS information in good condition.

Summarv of the Invention The invention in its various aspects is defined in the independent claims below, to which reference should now be made. Advantageous features of the invention are set forth in the appendant claims.

A preferred embodiment of the invention with several variants is described in more detail below with reference to the drawings. In this embodiment, a mobile telephone is equipped with a GPS unit and is enabled to accommodate the loss of GPS information from that GPS unit, due to loss of so signal resulting from use in a building, shopping mall, tunnel or vehicle, for example. The mobile includes means for determining whether or not the GPS unit successfully receives a GPS signal, and, if not, for causing the mobile telephone to transmit alternatively-derived GPS information in substitution for the position data from the GPS unit. This alternatively-derived GPS information comes from position data received from an external GPS unit (such as in a vehicle).

Preferably, the mobile telephone apparatus intermittently supplies power to the GPS unit, to reduce power consumption, and if the GPS unit does not successfully receive a GPS signal, the duration of the power supply off periods can be increased.

The mobile telephone apparatus may display map information, which can be obtained, in dependence upon the position information, over the internet. g

Where the substitute positional information comes from a base station, the base station can contain a second GPS unit to provide the substitute positional information.

Brief Description of the Drawings

Fig. 1 is a schematic view showing the basic structure of a mobile telephone system according to one embodiment of this invention; Fig. 2 is a schematic view showing the basic structure of a mobile telephone base station in the mobile telephone system illustrated in Fig. 1; Fig. 3 is a schematic view showing an arrangement in the case where to the mobile telephone apparatus in the mobile telephone system illustrated in Fig. 1 is fitted into an automobile and used in combination with an external GPS unit providing car navigation; Fig. 4 is a block diagram showing the basic structure of the mobile telephone apparatus in the mobile telephone system illustrated in Fig. 1; Fig. 5 is a flow chart showing the operation of communication control by a control section of the mobile telephone apparatus illustrated in Fig. 4; Fig. 6 is a timing chart showing the power supply waveform of a first GPS unit under power supply intermittent control by the control section of the mobile telephone apparatus illustrated in Fig. 4 in relation to an off period and so an on period; Fig. 7 is a timing chart showing the power supply waveform of the first GPS unit under the power supply intermittent control or power supply continuous control in dependence upon a radio communication (mobile communication) state under power supply control upon a radio section by the control section of the mobile telephone apparatus illustrated in Fig. 4; Fig. 8 is a timing chart showing the power supply waveform of the first GPS unit in dependence upon a GPS information reception (GPS reception) state under the power supply intermittent control upon the first GPS unit by the control section of the mobile telephone apparatus illustrated in Fig 4; so Fig. 9 is a flow chart showing the sequence of operations in a process of displaying map information in a display section of the mobile telephone apparatus in the mobile telephone system illustrated in Fig. 1; Fig. 10 is a timing chart showing the comparison between the power supply waveform in the case where the radio communication (mobile communication) state is an intermittent standby state under the power supply control upon the radio section and the power supply waveform of the first GPS unit under the power supply intermittent control when the timing of the power supply intermittent control by the control section of the mobile telephone apparatus in the mobile telephone system illustrated in Fig. 1 is changed; and Fig. 11 is a view exemplifying the transmission data format including time instant data and other data affixed upon transmission control of position data by To the control section of the mobile telephone apparatus in the mobile telephone system illustrated in Fig. 1.

Detailed Description of the Preferred Embodiment

In conjunction with an embodiment given below, description will be made in detail about a mobile telephone system of this invention with reference to the drawing.

Referring to Fig. 1, the mobile telephone system is constructed as a network system and comprises a mobile telephone apparatus 10, a mobile telephone base station 20, a GPS satellite 30, and a telephone network 40, and uses the internet 50. The GPS satellite 30 transmits GPS information including ho time instant information, position information, and map information. The mobile telephone apparatus 10 includes a first GPS unit adapted to receive the GPS information transmitted from the GPS satellite 30. The mobile telephone apparatus 10 is adapted to transmit via radio communication position data of the apparatus itself that is obtained by information processing with reference to the GPS information. The mobile telephone base station 20 is adapted to receive the position data via radio communication from the mobile telephone apparatus 10. The mobile telephone base station 20 includes a second GPS unit adapted to receive the GPS information transmitted from the GPS satellite 30 and including the time instant information, the position information, and the map so information. The mobile telephone base station 20 is adapted to transmit position information (applicable as the position data) of the station itself that is contained in the GPS information to the mobile telephone apparatus via radio communication. The telephone network 40 is connected to the mobile telephone base station 20. The internet 50 is connected to a router 40a equipped in the telephone network 40.

Specifically, the mobile telephone system described above has a basic function such that the mobile telephone apparatus 10 provided with the first GPS unit adapted to receive the GPS information transmitted from the GPS satellite obtains the position data of the apparatus itself by information processing with reference to the GPS information and reports the position data to the telephone network 40 connected to the mobile telephone base station 20 via radio communication to the mobile telephone base station 20. In addition, since To the mobile telephone base station 20 is provided with the second GPS unit adapted to receive the GPS information transmitted from the GPS satellite, the mobile telephone base station 20 has a function of acquiring position information of the station itself (preliminarily memorized as being identifiable for each individual station) contained in the GPS information and applicable as the position data and transmitting via radio communication the station position information by including it in report information to be reported to the mobile telephone apparatus 10.

This provides a function such that, in the case where the position data are to be reported to the telephone network 40 via radio communication to the so mobile telephone base station 20 and if the first GPS unit fails to appropriately receive the GPS information so that the position data can not be obtained, the mobile telephone apparatus 10 transmits, instead of that position data, the station position information obtained by the second GPS unit and supplied from the mobile telephone base station 20. As a consequence, even if a reception state of direct reception of the GPS information by the mobile telephone apparatus 10 is poor, it is possible to effectively utilize the GPS information from the GPS satellite 30 by substituting the position information of the base station itself contained in the GPS information and supplied from the mobile telephone base station 20 by the use of radio communication.

so Referring to Fig. 2, the mobile telephone base station 20 comprises a mobile telephone base section 22 adapted to carry out radio communication via a mobile antenna 21 and a second GPS unit 24 adapted to carry out GPS communication via a GPS antenna 23 and has a portable structure in which the mobile antenna 21 and the GPS antenna 23 are arranged on a same station building or housing. The mobile telephone base section 22 and the second GPS unit 24 are connected to each other. The mobile antenna 21 is connected to the mobile telephone base section 22 while the GPS antenna 23 is connected to the second GPS unit 24.

In the mobile telephone base station 20, the position information contained in the GPS information obtained by the use of the second GPS unit 24 can be transmitted via radio communication through the GPS antenna 23 to the mobile telephone apparatus 10. It is noted here that, if the mobile telephone base station 20 is arranged in a place beyond a radio wave of the GPS To information, such as an underground mall, the longitude and the latitude of the place of arrangement must be read from the map information or the like and stored in a memory. In the case where the mobile telephone base station 20 transmits the position information to the mobile telephone apparatus 10, the position information is superposed on the report information to be transmitted in common to all mobile telephone apparatuses 10 present in a communication area.

Referring to Fig. 3, the mobile telephone apparatus 10 of the above mentioned mobile telephone system is fitted into the automobile and used in combination with an external GPS unit 11 providing car navigation. The external so GPS unit 11 has a GPS antenna 17 arranged outside the automobile to serve as radio communication connecting means. Herein, the mobile telephone apparatus 10 is connected to the external GPS unit 11 providing the car navigation and adapted to receive the GPS information transmitted from the GPS satellite 30. In the mobile telephone system, in the case where the position s data are to be reported to the telephone network 40 via radio communication to the mobile telephone base station 20 and if the first GPS unit contained in the mobile telephone apparatus 10 fails to appropriately receive the GPS information so that the position data can not be obtained, the mobile telephone apparatus 10 transmits, instead of that position data, the position information so indirectly obtained from the external GPS unit 11 through the GPS antenna 17 by information processing. With this structure also, in the case where the reception state of direct reception of the GPS information at the mobile telephone apparatus 10 is poor, the GPS information from the GPS satellite 30 can effectively be utilized by substituting the position information contained in the GPS information and supplied from the external GPS unit 11 using radio communication through the GPS antenna 17.

Referring to Fig. 4, the mobile telephone apparatus 10 comprises a radio section 3 serving as a mobile telephone set adapted to carry out radio communication via a mobile antenna 1, a first GPS unit 6 adapted to carry out GPS communication via a GPS antenna 7, a control section 5 connected between the radio section 3 and the first GPS unit 6 for carrying out communicating operation control upon radio communication and GPS communication, an operating section 4 having a plurality of key switches for to requesting control operation at the control section 5, and a display section 2 for displaying display data supplied from inside and outside of the apparatus. The control section 5 is connected not only to the radio section 3 connected to the mobile antenna 1 and the first GPS unit 6 connected to the GPS antenna 7 but also to the display section 2 and the operating section 4.

Among other things, the control section 5 carries out communicating operation control upon radio communication and GPS communication and power supply intermittent control for intermittently energizing the first GPS unit 6 so that the first GPS unit 6 is intermittently turned on under the power supply intermittent control. Herein, the control section 5 carries out power supply control so to energize the radio section 3 upon radio communication under the communicating operation control, carries out power supply intermittent control only when the radio communication is in an intermittent standby state, and carries out power supply continuous control to continuously energize the first GPS unit 6 when the radio communication is in a busy state. Thus, the first GPS unit 6 is continuously turned on under the power supply continuous control.

Referring to Fig. 5, the operation of the communicating operation control of the control section 5 in the mobile telephone apparatus 10 will be described.

Herein, the mobile telephone apparatus 10 is required to transmit the position data through the mobile telephone base station 20 to the telephone network 40.

At first, when the operation is started, the control section 5 judges whether or not the first GPS unit 6 successfully receives a radio wave of current GPS information by detecting the presence or absence of the GPS wave (step S1). In the presence of the GPS wave, GPS positioning is performed in which the first GPS unit 6 carries out positioning with reference to the current GPS information (step S2) and then acquires position information contained in the GPS information (step S5). Thereafter, the position information acquired is subjected to information processing to obtain the position data. The position data are transmitted (step S6) and the operation comes to an end.

On the other hand, in the absence of the GPS wave as a result of judgment of whether or not the GPS wave is present (step S1), the control unit 5 judges whether or not connection with the external GPS unit 11 is possible (step S3). If connection is possible, the external GPS unit 11 acquires position information contained in the GPS information (step S5). Thereafter, the position to information acquired is subjected to information processing to obtain the position data. The position data are transmitted (step S6) and the operation comes to an end. If connection is impossible, use is made of the position information supplied from the second GPS unit 24 of the mobile telephone base station 20 (step S4).

After the position information is acquired (step S5), the position data obtained by information processing of the position information acquired is transmitted (step S6) and the operation comes to an end.

Referring to Fig. 6, the power supply waveform of the first GPS unit 6 is illustrated in relation to an off period T1 and an on period T2 under the power supply intermittent control by the control section 5 of the mobile telephone so apparatus 10. Herein, the control section 5 carries out power supply to the first GPS unit 6 under the power supply intermittent control in which the off period T1 and the on period T2 are successively continued as illustrated in the Figure. The on period T2 is a minimum time interval required for reception of the radio wave.

The off period T1 is selected to be a time interval of the order of 10 times that of z the on period T2.

Herein, upon determining reception of the radio wave of the GPS information during the on period T2, the control section 5 temporarily interrupts the power supply intermittent control and starts the power supply continuous control to continuously energize the first GPS unit 6. As a consequence, the first so GPS unit 6 is continuously turned on to receive the GPS information. When the reception of the GPS information is completed, the power supply intermittent control is carried out again at the timing illustrated in Fig. 6. Also in the case where the position data are required to be transmitted by the use of the first GPS unit 6, the control section 5 temporarily interrupts the power supply intermittent control and starts the power supply continuous control to continuously energize the first GPS unit 6 in the similar manner. The first GPS unit 6 is continuously turned on to perform transmission of the position data. At the time instant when the transmission of the position data is completed, the power supply intermittent control is again carried out. Furthermore, in the case where the first GPS unit 6 can not receive the GPS information continuously for a predetermined time duration or more under the communicating operation control, the control section 5 increases the power supply off period in the power supply intermittent control.

to Referring to Fig. 7, illustrated is the power supply waveform of the first GPS unit 6 under the power supply intermittent control or the power supply continuous control depending upon the radio communication (mobile communication) state under the power supply control upon the radio section 3 by the control section 5 in the mobile telephone apparatus 10. Herein, if the us radio communication by the first radio section 3 is in the intermittent standby state, the control section 5 carries out the power supply intermittent control upon the first GPS unit 6. If the radio communication is in the busy state, the control section 5 carries out the power supply continuous control upon the first GPS unit 6. Furthermore, if the radio communication reaches a communication end point, so the control section 5 again carries out the power supply intermittent control upon the first GPS unit 6.

Herein, the control section 5 confirms the reception state of the radio wave of the GPS information in the power supply intermittent control upon the first GPS unit 6. In the case of normal reception, the control section 5 carries out :s the power supply intermittent control at a timing identical with that illustrated in Fig. 6. On the other hand, in the case where no radio wave is received consecutively for a predetermined time duration or more, the power supply off period under the power supply intermittent control is increased as illustrated in Fig. 8 (for example, an off period T3 illustrated in Fig. 8 has an extended time so interval corresponding to about twice that of the off period T1). Upon reception of the radio wave, the off period is returned to the initial preselected time interval. Thus, low current consumption is achieved.

Although the above-mentioned mobile telephone apparatus 10 is provided with the first GPS unit 6 for carrying out GPS communication, the control section 5 carries out the power supply intermittent control only in the intermittent standby state of radio communication under the communicating operation control to intermittently turn on the first GPS unit 6. Therefore, the current consumption is reduced to reduce the power consumption.

In the meanwhile, the above-mentioned mobile telephone apparatus 10 comprises the operating section 4 having a plurality of key switches for requesting the control operation including the power supply control and the power supply intermittent control by the control section 6. The key switches of the operating section 4 include a mobile power supply key for requesting to switching operation between on and off of power supply to the radio section 3 upon power supply control by the control section 5, and a communication power supply key for requesting switching operation between on and off of intermittent power supply to the first GPS unit 6 upon power supply intermittent control by the control section 5. It is noted here that, even if the power supply control is turned off by the mobile power supply key of the operating section 4, the control section 5 carries out power supply intermittent control to intermittently turn on the first GPS unit 6 as far as the power supply intermittent control is turned on by the communication power supply key. Thus, the control section 5 detects and memorizes on or off of the mobile power supply key and on or off of the communication power supply key every time when the mobile power supply key or the communication power supply key of the operating section 4 is pressed.

Description will now be made of the power supply control operation upon the first GPS unit 6 by the control section 5 in response to on or off of the mobile power supply key and the communication power supply key of the operating section 4. The control section 5 carries out the power supply control operation upon the first GPS unit 6 in response to on or off of the communication power supply key irrespective of on or off of the mobile power supply key in the operating section 4. Specifically, if the communication power supply key is turned on, the control section 5 carries out the power supply intermittent control.

so If the communication power supply key is turned off, the control section 5 carries out power supply off control to turn off the first GPS unit 6. Thus, the control section 5 suspends the control operation if both of the mobile power supply key and the communication power supply key are turned off. If either one of the mobile power supply key and the communication power supply key is pressed, the control operation is stopped leaving the detecting function.

As described above, the control section 5 extends the power supply off interval in the power supply intermittent control upon the first GPS unit 6 if the first GPS unit 6 can not receive the GPS communication. Alternatively, the key switches in the operating section 4 separately include the mobile power supply key for requesting switching operation between on and off of power supply to the radio section 3 and the communication power supply key for requesting switching operation between on and off of the intermittent power supply to the to first GPS unit 6. Thus, the radio section 3 and the first GPS unit 6 can individually be turned on and off. This also serves to reduce the current consumption.

Summarizing, in the above-mentioned mobile telephone apparatus 10, the operating section 4 turns on the power supply control by the use of the mobile power supply key and turns off the power supply intermittent control by the communication power supply key upon the radio communication under the communicating operation control as a normal state. The operating section 4 turns on the power supply intermittent control in the case where transmission of the position data or reception of position information by the GPS communication so is required and turns off the power supply intermittent control in the case where the GPS communication is completed. At this time, the control section 5 carries out the power supply intermittent control upon reception of the GPS information (position information) to intermittently turn on the first GPS unit 6. The above-mentioned mobile telephone apparatus 10 comprises the display

section 2 adapted to display map data. Upon displaying the map data in the display section 2, the mobile telephone apparatus 10 has a function of receiving map information applicable as the map data from the telephone network 40 via radio communication from the mobile telephone base station 20 by the use of the internet homepage connected through the internet 50 and the so router 40a to the telephone network 40, with reference to one of the position data directly obtained from the first GPS unit 6 contained in the apparatus by information processing of the GPS information, the position information indirectly obtained from the second GPS unit 24 through radio communication from the mobile telephone base station 20 by information processing of the GPS information, and the position information indirectly obtained from the external GPS unit 11 via radio communication through the GPS antenna 17 by information processing of the GPS information.

Referring to Fig. 9, description will now be made of the sequence of s operations in a process of displaying the map information in the display section 2 in the above-mentioned mobile telephone apparatus 10. Herein, the mobile telephone apparatus 10 carries out a call originating operation to establish connection with the telephone network 40 through the mobile telephone base station 20. Thereafter, the mobile telephone apparatus 10 produces a to connection request with the internet 50. The connection with the internet 50 is established and the homepage providing the map information is accessed. The communication sequence mentioned above is similar to the connection protocol in the existing mobile telephone system. Herein, the mobile telephone apparatus transmits, via the telephone network 40 to the internet 50, the center :s latitude/longitude data representative of the center latitude and the center longitude, scale data representative of the scale, and screen range data representative of the screen range. As a result, the mobile telephone apparatus receives the map information transmitted via the telephone network 40 through the internet 50, and carries out information processing of the map JO information to produce the map data which are displayed in the display section 2.

If the map information contained in the GPS information received by the second GPS unit 24 of the mobile telephone base station 20 itself can be transmitted to the mobile telephone apparatus 10 via radio communication, the s map information is available without relying upon the internet 50. Furthermore, the map information can directly be obtained from the mobile telephone base station 20 by the first GPS unit 6 contained in the mobile telephone apparatus itself. However, since a wide variety of map information is accumulated in internet homepages at present, the structure utilizing the internet 50 is superior so in convenience and eliminates the need of enormous facility investment for the mobile telephone base station 20.

As a consequence, even if the reception state of direct reception of the GPS information is poor in the mobile telephone apparatus 10, the GPS information from the GPS satellite 30 can effectively be utilized by indirectly obtaining the GPS information derived from the telephone network 40 utilizing the internet homepage and sent via the radio communication from the mobile telephone base station 20 and substituting the map information contained therein as the map data.

Furthermore, the above-mentioned mobile telephone apparatus 10 comprises a clock section (not shown) indicating the time instant. Upon indication of the time instant at the clock section, the mobile telephone apparatus 10 is periodically corrected with reference to one of: the time instant data directly obtained from the first GPS unit 6 contained therein by information to processing of the GPS information, time instant information indirectly obtained from the second GPS unit 24 via radio communication from the mobile telephone base station by information processing of the GPS information, and the time instant information indirectly obtained from the external GPS unit 11 via radio communication through the GPS antenna 17 by information processing of the GPS information.

Specifically, the mobile telephone apparatus 10 performs a basic operation in which the first GPS unit 6 contained therein receives the radio wave of the GPS information. In the case where the first GPS unit 6 can not receive the radio wave of the GPS information, the control section 5 carries out so information processing of the time instant information indirectly obtained from the second GPS unit 24 via radio communication from the mobile telephone base station 20 by information processing of the GPS information, or of the time instant information indirectly obtained from the external GPS unit 11 via radio communication through the radio communication connecting means by :s information processing of the GPS information. Thus, the time instant data are obtained to correct the time instant indication by a clock function provided in the apparatus. The clock function of the control section 5 itself is less accurate than the realtime indication of the quartz oscillator, such as the clock information of the GPS information. Under these circumstances, the function of correcting the so time instant is effective to improve of the time instant indication of the mobile telephone apparatus 10. It is noted here that the correction of the time instant can be carried out periodically at a predetermined time instant (for example, 0:00 AM) in a day. Alternatively, the timing of the interval can be selected to any desired timing, for example, every one hour or every six hours.

Referring to Fig. 10, comparison is made between the power supply waveform in the case where the radio communication (mobile communication) state is an intermittent standby state under the power supply control upon the radio section 3, and the power supply waveform of the first GPS unit 6 under the power supply intermittent control when the timing of the power supply intermittent control by the control section 5 of the mobile telephone apparatus 10 in the mobile telephone system is changed.

Herein, the power supply intermittent control by the control section 5 upon the first GPS unit 6 is carried out in synchronism with the timing of the to intermittent standby state of the radio communication state under the power supply control upon the radio section 3. As a consequence, the power supply waveform of the first GPS unit 6 under the power supply intermittent control is coincident with the power supply waveform of the radio section 3 in the intermittent standby state under the power supply control.

With the above-mentioned structure, as compared with the case where the power supply control upon the radio section 3 and the power supply intermittent control upon the first GPS unit 6 are separately carried out by the control section 5 in the mobile telephone apparatus 10, the current consumption can further be reduced because the receiving operations of both the radio go section 3 and the first GPS unit 6 can simultaneously be carried out.

In this case, it is only necessary that the enabling of the power supply of the first GPS unit 6 is synchronized with the timing of the intermittent standby state of the mobile telephone apparatus 10. In the example illustrated in Fig. 10, every time the power supply waveform of the mobile telephone apparatus 10 in : the intermittent standby state rises, the power supply waveform of the first GPS unit 6 also rises into an on state. Alternatively, a modification is possible in which the power supply waveform of the first GPS unit 6 rises once per N times the power supply waveform of the intermittent standby of the mobile telephone apparatus 10 rises. It is also effective if the waveform of the first GPS unit 6 so does not rise if the mobile telephone apparatus 10 is used outside a GPS communication zone. Furthermore, upon using the mobile telephone apparatus 10, control is carried out so that the first GPS unit 6 is turned off in the normal state, is turned on when the position information is required, and is turned off when the position information is received. In this manner, the current consumption can be reduced.

Finally, description will be made of a bypass function in the case where the first GPS unit 6 contained in the mobile telephone apparatus 10 can not appropriately receive the GPS information including the position information.

The first GPS unit 6 of the mobile telephone apparatus 10 illustrated in Fig. 4 always memorizes the position data representative of the position information and the time instant data representative of the time instant information as a pair and does not update the position data if the radio wave of the GPS information to can not be received. If the position data are required, the control section 5 inquires of the first GPS unit 6 about the reception state of the radio wave of the GPS information. If reception is impossible, the position data memorized by the first GPS unit are acquired and transmitted to the mobile telephone base station together with the time instant data memorized, as a pair.

Fig. 11 exemplifies the format of the transmission data including the time instant data provided upon transmission control of the position data by the control section 5 of the mobile telephone apparatus 10 in the mobile telephone system, as well as other data. Herein, when the mobile telephone apparatus 10 sends the position data to the telephone network 40 via radio communication to so the mobile telephone base station 20, those data representative of the acquiring method and the acquiring time instant related to the position data, the current time instant, and the reception state (internal GPS reception state) of the first GPS unit 6 are provided together as the transmission data.

The mobile telephone apparatus 10 has the function of transmitting, in the case where the position data are to be reported to the telephone network 40 via radio communication to the mobile telephone base station 20 and if the first GPS unit 6 fails to appropriately receive the GPS information so that the position data cannot be obtained, appropriate previous data namely that most recently obtained instead of the current data in the transmission data containing the so position data. The mobile telephone apparatus 10 also has another function of transmitting, upon transmission of the previous data in the transmission data containing the position data, the time instant data representing the time instant when the previous data are acquired and obtained by information processing with reference to the GPS information. As a consequence, even if the reception 1' state of direct reception of the GPS information at the mobile telephone apparatus 10 is poor, the mobile telephone base station 20 in the mobile telephone system can acquire detailed data of another mobile telephone apparatus 10 as another party in a good reception state immediately before.

Consideration will now be made of the case where the mobile telephone apparatus 10 has the function of transmitting the previous data and, upon displaying operation of the map data in the display section 2 by the use of the internet homepage, selects the position data directly obtained from the first GPS unit 6 contained in the apparatus by information processing of the GPS to information. In this event, in the case where the position data are to be reported to the telephone network 40 via radio communication to the mobile telephone base station 20 and if the first GPS unit 6 fails to appropriately receive the GPS information so that the position data can not be obtained, the appropriate previous data can be selected and transmitted instead of the current data.

It is assumed that the transmission data are transmitted in the abovementioned manner. In this event, even if the first GPS unit 6 contained in the mobile telephone apparatus 10 can not receive the radio wave of the GPS information, the control section 5 memorizes the position information and the time instant information at the time instant when the first GPS unit 6 has appropriately received the GPS information immediately previously and, under the transmission control, the transmission data containing the position data and the time instant data obtained by information processing of those information are transmitted through the mobile telephone base station 20 to another party involved in communication. Thus, it is possible to know where the user of the mobile telephone apparatus 10 has been at least at a particular time instant.

This provides utility data which greatly benefits another person who wants to know the position of the user of the mobile telephone apparatus 10 (for example, who receives an emergency report).

As described above, the mobile telephone system described has a basic so structure in which the mobile telephone base station has the function of reporting the position information of the station itself to the mobile telephone apparatus. In addition, the mobile telephone apparatus has the function of transmitting the position data obtained by information processing of the position information contained in the GPS information selectively obtained from one of: the first GPS unit contained in the mobile telephone apparatus, the second GPS unit provided in the mobile telephone base station, and the external GPS unit connected through the radio communication connecting means. Therefore, even if the first GPS unit contained in the mobile telephone apparatus fails to receive the radio wave of the GPS information, position data can be transmitted to the mobile telephone base station. As a result, even if the reception state of direct reception of the GPS state at the mobile telephone apparatus is poor, the GPS information can effectively be utilized by the use of radio communication.

The mobile telephone system described above has the function of to receiving, upon displaying the map data in the display section contained, the map information applicable as the map data from the telephone network via radio communication from the mobile telephone base station by the use of an internet homepage connected through the internet and the router to the telephone network, with reference to one of: the position data directly obtained from the first GPS unit by information processing of the GPS information, the position information indirectly obtained from the second GPS unit via radio communication from the mobile telephone base station by information processing of the GPS information, and the position information indirectly obtained from the external GPS unit via radio communication through the radio so communication connecting means by information processing of the GPS information. Furthermore, the system has the function of periodically correcting the indication of the time instant at the clock section contained in the apparatus, with reference to one of: the time instant data directly obtained from the first GPS unit by information processing of the GPS information, the time instant information indirectly obtained from the second GPS unit via radio communication from the mobile telephone base station by information processing of the GPS information, and the time instant information indirectly obtained from the external GPS unit via radio communication through the radio communication connecting means by information processing of the GPS so information. Therefore, it is possible to easily obtain and utilize the map information, to indicate the accurate time instant, and to achieve the reduction in size, weight, and cost because of low memory capacity, without requiring an enormously large memory capacity for the map data.

Furthermore, the mobile telephone apparatus includes the control section for carrying out the communicating operation control upon the radio communication at the radio section serving as a mobile telephone set adapted to carry out radio communication and upon the GPS communication at the first GPS unit contained therein. The control section carries out power supply control to energize the radio section upon the radio communication, carries out the power supply intermittent control to intermittently energize the first GPS unit only when the radio communication is in the intermittent standby state, and carries out the power supply continuous control to continuously energize the first GPS To unit when the radio communication is in the busy state. This provides the function of intermittently turning on the power supply to the first GPS unit having large current consumption to minimize the power supply so that low power consumption of the mobile telephone apparatus is achieved.

In particular, in the above-mentioned mobile telephone apparatus, in the case where the first GPS unit contained therein fails to receive the radio wave of the GPS information, the control section increases the interval of the power supply off period in the power supply intermittent control for the first GPS unit.

Alternatively, the operating section separately includes as the key switches the mobile power supply key for requesting switching operation go between on and off the power supply to the radio section, and the communication power supply key for requesting switching operation between on and off of the intermittent power supply to the first GPS unit. With this structure, the radio section and the first GPS unit can individually be turned on and off.

This achieves further reduction in current consumption (reduction in power :s consumption). Furthermore, the system is given the function such that the first GPS unit continuously acquires the position information if the mobile power supply key alone is turned off in the case where the radio communication by the mobile telephone apparatus is not necessary. In addition, in case of emergency, the mobile power supply key is immediately turned on to immediately transmit so the position data.

Claims (7)

1. A mobile telephone system comprising: a mobile telephone base station for connection to a telephone network; and mobile telephone apparatus comprising a first GPS unit for receiving a GPS wave as a received GPS signal to obtain position data of the mobile telephone apparatus by information processing with reference to the received GPS signal, and a radio section connected to the first GPS unit for transmitting, by radio communication, the position data of the mobile telephone apparatus to to the mobile telephone base station to make the mobile telephone base station inform the telephone network of the position data of the mobile telephone apparatus; and an external GPS unit external of the mobile telephone apparatus for receiving a GPS wave as an external received GPS signal to obtain external position data of the mobile telephone apparatus by information processing with reference to the external received GPS signal; the mobile telephone apparatus further comprising means for determining whether or not the first GPS unit successfully receives a GPS signal and, if it determines that the first GPS unit does not successfully receive a GPS so signal, for causing the mobile telephone apparatus to transmit the position information received from the external GPS unit in substitution for the position data from the first GPS unit.

2. A mobile telephone system as claimed in claim 1, wherein the mobile telephone apparatus further comprises a control section for carrying out power supply intermittent control to intermittently energize the first GPS unit so that the first GPS unit is intermittently turned on under the power supply intermittent control.

3. A mobile telephone system as claimed in claim 2, wherein, when the mobile telephone apparatus determines that the first GPS unit does not so successfully receive a GPS signal, the control section increases the duration of power supply off periods in the power supply to the first GPS unit.

4. A mobile telephone system as claimed in any of claims 1 to 3, wherein the mobile telephone apparatus further comprises a display section for displaying map information specified by either the external position data or the position data of the mobile telephone apparatus, the mobile telephone apparatus receiving, upon display of the map information in the display section, the map information through the mobile telephone base station from the telephone network by transmitting the external position data or the position data of the mobile telephone apparatus through the mobile telephone base station to the telephone network.

to

5. A mobile telephone system as claimed in claim 4, wherein the map information is obtained by the use of an internet homepage connected through a router to the telephone network.

6. A mobile telephone system as claimed in any of claims 1 to 5, wherein, when the mobile telephone apparatus determines that the first GPS unit does s not successfully receive a GPS signal, the mobile telephone apparatus obtains time information from the external GPS unit.

7. Mobile telephone apparatus comprising: a first GPS unit for receiving a GPS wave as a received GPS signal to obtain position data of the mobile telephone apparatus by information so processing with reference to the received GPS signal; a radio section connected to the first GPS unit for transmitting, by radio communication, the position data of the mobile telephone apparatus to a mobile telephone base station; an external GPS unit external of the mobile telephone apparatus for receiving a GPS wave as an external received GPS signal to obtain external position data of the mobile telephone apparatus by information processing with reference to the external received GPS signal; and means for determining whether or not the first GPS unit successfully receives a GPS signal and, if it determines that the first GPS unit does not so successfully receive a GPS signal, for causing the mobile telephone apparatus to transmit the position data received from the external GPS unit in substitution for the position data from the first GPS unit.