JP2007019625A - Mobile terminal and authentication control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile terminal capable of enhancing the convenience of a possessor or the like, and to provide an authentication control method. <P>SOLUTION: The mobile terminal 200 is provided with: a wireless authentication section 310 for transmitting and receiving a wireless signal to and from a wireless communication unit 100 to carry out wireless authentication; a use restraining control section 340 for controlling the permission and restriction of the use of functions installed to the mobile terminal 200 on the basis of an estimated apart distance with the wireless authentication section 310; and an apart distance calculation section 320 for calculating the estimate apart distance on the basis of a reception level of the wireless signal transmitted with prescribed strength by using carriers with first and second frequencies. Consequently, since the permission and restriction of the use of the mounted functions can be controlled on the basis of the estimate apart distance closer to an actual apart distance calculated on the basis of the reception level of the carriers with two different frequencies transmitted at prescribed strength, the occurrence of a malfunction can be prevented, resulting in that the convenience of a possessor or the like can be enhanced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a portable terminal device and an authentication control method for performing wireless authentication by transmitting and receiving wireless signals to and from a wireless communication unit.

  As a measure to prevent personal information leakage due to misplacement or theft of mobile phones, a receiver that restricts the mobile phone's call function to a certain distance from the owner is built into the mobile phone and wirelessly connected to this receiver. If the owner always puts a card with a transmitter that sends a signal in his / her chest pocket, etc., and the mobile phone moves away from the owner by a certain distance due to misplacement or theft, the signal from the transmitter weakens automatically In addition, there is a proposal that restricts the internal operation of a mobile phone.

  In such a mobile phone, even if the owner misplaces or stolen his / her mobile phone and does not immediately notice it, the use restriction is automatically activated on the mobile phone, and the non-owner has a transmitter card. Unless the mobile phone can be used, the mobile phone cannot be used, and it is possible to effectively prevent misplacement or theft without automatic operation for restricting the use.

  However, even a mobile phone having such a use restriction function does not have means to warn the owner that a misplacement or theft has occurred, so there is still a possibility that it may be delayed to notice that. Remain. Although it is extremely rare, if the release signal from the transmitter card that releases the restriction on the use of the above mobile phone is decrypted, or if the modification that stops only the use restriction function in the mobile phone is made, it is illegal. Unexpected situations where use and unauthorized use cannot be prevented are also expected.

  As a method to solve this, if a device such as a mobile phone leaves the owner or the user due to misplacement or theft, the device itself becomes unusable and can warn that the device has been separated by more than a certain distance Is proposed in Patent Document 1.

Specifically, a wireless communication unit that includes a transmitter and a receiver and sends an identification code signal from the transmitter at a constant intensity, and a receiver and a transmitter that are used based on the identification code signal received by the receiver. A signal for canceling the restriction is sent to the mobile phone and a confirmation code signal of the same code signal is transmitted from the transmitter with a certain strength to the mobile phone, and the distance between the two units is If the identification code signal received from the wireless communication unit is within a certain range, the confirmation code signal is transmitted from the use restriction canceling unit based on the signal detected that the identification code signal is its own, and the use restriction solution signal is sent to the mobile phone. When the distance between the two units exceeds a certain level, the reception level of the code signal from the counterpart unit is determined in each unit. If a value below the use restriction release unit stops the feeding of the use restriction release signal, the identification signal transmitting unit use restriction device of the apparatus, characterized in that adapted to emit a warning signal it has been proposed.
Japanese Patent No. 293276

  However, there are various situations in which the use restriction device is used. For example, when there is an obstacle between the identification signal transmission unit and the use restriction release unit, the actual condition between both units It is assumed that there is a large gap (error) between the separation distance and the estimated value. If the error is large, the use restriction control of the mobile phone may malfunction.

  The present invention has been made in view of such points, and by using a more accurate estimated distance from the wireless communication unit, it is possible to prevent malfunctions and improve convenience for the owner and the like. An object of the present invention is to provide a portable terminal device and an authentication control method.

  The portable terminal device according to the present invention is configured to permit use of the installed function based on an estimated separation distance between a wireless authentication unit that performs wireless authentication by transmitting and receiving a wireless signal to and from the wireless communication unit, and the wireless communication unit. And a separation distance for calculating the estimated separation distance based on a reception level of the radio signal transmitted at a constant intensity using a carrier of the first frequency and the second frequency, and a use restriction means for controlling the use restriction And a calculating means.

  An authentication control method of the present invention is an authentication control method for performing wireless authentication by transmitting and receiving a wireless signal between a wireless communication unit and a use restriction releasing unit in a portable terminal device, and includes a first frequency and a second frequency A calculation step of calculating an estimated separation distance between the two units based on a reception level of the radio signal transmitted at a constant intensity using a carrier of a frequency, and based on the estimated separation distance, And a step of controlling permission and restriction of use of the on-board function.

  ADVANTAGE OF THE INVENTION According to this invention, the portable terminal device and authentication control method which can improve the convenience of an owner etc. can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the embodiment, the same components are denoted by the same reference numerals, and the description thereof will be omitted because it is duplicated.

(Embodiment 1)
As illustrated in FIG. 1, the wireless communication unit 100 according to the use restriction device of the first embodiment includes a wireless authentication unit 110, an alarm circuit 120, and an external output unit 130. The wireless authentication unit 110 includes a transmission / reception unit 140, a received signal level detection unit 150, a wireless authentication control unit 160, and an authentication ID storage unit 170.

  The transmission / reception unit 140 receives a confirmation signal (this confirmation signal is also used as identification information of the use restriction release unit) transmitted from the use restriction release unit of the use restriction device, which will be described later, via the antenna. The data is output to the level detection unit 150 and the wireless authentication control unit 160. In addition, the transmission / reception unit 140 receives the identification code of the wireless communication unit 100 from the wireless authentication control unit 160 and transmits it via the antenna.

  The reception signal level detection unit 150 detects the reception level of the confirmation signal for each frequency of the carrier used when the confirmation signal is transmitted, and outputs the reception level information of each frequency to the wireless authentication control unit 160.

  The wireless authentication control unit 160 determines whether or not the confirmation signal from the transmission / reception unit 140 corresponds to the identification code of the wireless communication unit 100 stored in the authentication ID storage unit 170. In this determination, the wireless communication unit 100 and the use restriction release unit are used in pairs, and it is possible to prevent unauthorized use and unauthorized use of the target device to which the use restriction release unit is attached only after they can be distinguished from each other. This is done to prevent unauthorized use and unauthorized use of the target device.

  When the wireless authentication control unit 160 determines that the confirmation signal and the identification code correspond to each other as a result of the determination, the wireless authentication control unit 160 determines whether the use restriction release unit is based on the reception level information from the reception signal level detection unit 150. The estimated separation distance is calculated, and a signal is output to the alarm circuit 120 when the estimated separation distance is equal to or greater than a predetermined threshold value.

  When the wireless authentication control unit 160 determines that the confirmation signal and the identification code correspond to each other as a result of the determination, the wireless authentication control unit 160 receives the reception level information from the reception signal level detection unit 150 (the reception level information includes the identification level). Is transmitted to a use restriction releasing unit to be described later via the transmission / reception unit 140.

  The alarm circuit 120 operates when a signal from the wireless authentication control unit 160 is input. Then, depending on the type of the external output unit 130, the target device with the use restriction release unit is left misplaced or stolen by a user carrying the wireless communication unit 100 by voice, light, vibration, or the like. Give a warning about leaving.

  As shown in FIG. 2, the mobile terminal device 200 of the first embodiment includes a mobile terminal function control unit 210, a transmission unit 220, and a reception unit 230, and further uses according to the use restriction device of the first embodiment. A restriction releasing unit 300 is attached. The use restriction release unit 300 includes a wireless authentication unit 310, a separation distance calculation unit 320, a memory 330, and a use restriction control unit 340. The wireless authentication unit 310 includes a transmission / reception unit 350, a wireless authentication control unit 360, and an authentication ID storage unit 370. The mobile terminal device 200 is, for example, a mobile phone, a PDA, a notebook computer, an MP3 player, an HDD player, or the like. In addition, here, the use restriction canceling unit 300 of the use restriction device is provided as a separate body from the mobile terminal device 200, and the description will be made on the assumption that the use restriction releasing unit 300 is attached to the mobile terminal device 200 and used. However, the present invention is not limited thereto. Instead, the portable terminal device 200 may have the use restriction releasing unit 300 mounted therein, that is, may be built therein.

The transmission / reception unit 350 includes a frequency oscillator 380 and a frequency oscillator 390 that generate carriers of _two different frequencies f ₁ and f ₂ (f ₁ > f ₂ ), and the confirmation signal from the wireless authentication control unit 360 is 2 The signals are placed on one carrier and transmitted to the wireless communication unit 100 via an antenna. In addition, the transmission / reception unit 350 receives the identification code from the wireless communication unit 100 and outputs it to the wireless authentication control unit 360. Further, the transmission / reception unit 350 receives the reception power level information in the wireless communication unit 100 of the confirmation signal transmitted on the two carriers and outputs it to the wireless authentication control unit 360.

  The wireless authentication control unit 360 determines whether or not the identification code from the transmission / reception unit 350 corresponds to the identification information of the use restriction releasing unit 300 stored in the authentication ID storage unit 370. This determination is performed in order to prevent unauthorized use and unauthorized use of the target device (here, the mobile terminal device 200), similarly to the determination in the wireless authentication control unit 160 of the wireless communication unit 100.

  When the wireless authentication control unit 360 determines that the identification code and the identification information correspond to each other as a result of the determination, that is, when the authentication is successful, the wireless authentication control unit 360 outputs a confirmation signal to the transmission / reception unit 350. Then, the wireless authentication control unit 360 transmits the confirmation signal to the wireless communication unit 100, and as a result of the determination using the received power level information transmitted from the wireless communication unit 100, the identification code and the identification information are obtained. When it is determined that it is compatible, the reception level information from the transmission / reception unit 350 is output to the separation distance calculation unit 320.

  The separation distance calculation unit 320 stores the received power information from the wireless authentication control unit 360 in the memory 330. The memory 330 stores various data for calculating the estimated separation distance. Then, the estimated separation distance between the wireless communication unit 100 and the use restriction releasing unit 300 is calculated based on the reception level information relating to the two different frequency carriers used for transmitting the confirmation signal and the various data. Details of this calculation method will be described later.

  Then, the separation distance calculation unit 320 outputs the calculated estimated separation distance to the use restriction control unit 340.

  The use restriction control unit 340 receives the estimated separation distance and compares it with a threshold value. If the estimated separation distance is less than the threshold value as a result of the comparison, the use restriction control unit 340 outputs a use restriction release signal to the mobile terminal function control unit 210. On the other hand, if the estimated separation distance is equal to or greater than the threshold value as a result of the comparison, the use restriction control unit 340 stops outputting the use restriction release signal to the mobile terminal function control unit 210. By doing so, the function of the mobile terminal can be deactivated according to the comparison result between the estimated separation distance between the wireless communication unit 100 and the use restriction releasing unit 300 and the threshold value. That is, when the estimated separation distance between the wireless communication unit 100 and the use restriction release unit 300 is large, the user of the mobile terminal device 200 holding the wireless communication unit 100 has been stolen or misplaced. Therefore, it is possible to prevent unauthorized use and unauthorized use by stopping the functions of the mobile terminal device 200 from being used by others.

  The mobile terminal function control unit 210 can use the functions of the mobile terminal device 200 because the mobile terminal device 200 is likely to be near the user while receiving the use restriction release signal from the use restriction control unit 340. Control to the state. On the other hand, when the mobile terminal function control unit 210 does not receive the use restriction release signal from the use restriction control unit 340, it is highly likely that the mobile terminal device 200 is located away from the user. Is controlled so that it cannot be used. In addition, when the mobile terminal function control unit 210 is in a state where the mobile function can be used, depending on the function (for example, telephone function, mail function, Internet function, etc.) Controls communication with the device.

  In the above description, the use restriction control unit 340 controls the mobile terminal function control unit 210 by outputting the use restriction release signal and stopping the output. However, the use restriction control unit 340 is not limited to this, and the use restriction control is not limited thereto. The mobile terminal function control unit 210 may be controlled by the unit 340 outputting a use permission signal or a use non-permission signal according to the result of the comparison.

  Next, a method for calculating the estimated separation distance in the separation distance calculation unit 320 will be described.

  First, the relationship between the frequency of the carrier to be used and the propagation loss (propagation loss) will be discussed with reference to FIGS. 3 and 4 while considering the presence or absence of an obstacle in the propagation path.

  As shown in FIG. 3, when there is no obstacle in the propagation path, the relationship between the distance and the propagation loss is substantially constant regardless of the carrier frequency. Therefore, when there is no obstacle, a single estimated separation distance can be obtained using the curve L1 in FIG.

  However, when there are obstacles in the propagation path, high frequencies tend to go straight and low frequencies tend to wrap around. There is. Therefore, a curve L2 related to low frequency appears when the curve L1 when there is no obstacle is shifted upward as a whole, and a curve L3 related to high frequency appears when it is further shifted upward.

  When there is an obstacle in the propagation path, the propagation loss is measured with two different frequency carriers, and the separation distance is obtained from the propagation loss, as shown in FIG. 4, the separation distance obtained from each of the two frequencies. Will take different values. Here, the difference in the separation distance obtained from each of the two frequencies (which corresponds to the difference in propagation loss) is an index for estimating the propagation environment such as the amount of obstacles and the positional relationship in the propagation path. By using the difference in the separation distance and the value of the separation distance obtained from each of the two frequencies, it is possible to calculate an estimated separation distance that is closer to the actual separation distance, that is, with high accuracy.

Therefore, the separation distance calculation unit 320 inputs reception level information related to carriers of _two different frequencies (f ₁ , f ₂ ) received from the wireless authentication control unit 360. Further, the memory 330 and the curve (e.g., L3 in FIG. 4) corresponding to the frequency _{f 1} curve (e.g. L2 in FIG. 4) corresponding to the frequency _{f 2} are prepared. Then, the separation distance calculation unit 320 first calculates a propagation loss corresponding to each frequency by subtracting the value indicated by each reception level information from the power value transmitted from the transmission / reception unit 350. Then, the estimated separation distance is calculated as described above using a correspondence curve between each obtained propagation loss value and the propagation loss and separation distance stored in the memory 330. Note that the above correspondence curve differs depending on the propagation environment such as the amount of obstacles in the propagation path, positional relationship, etc. even if the frequency is the same, so the correspondence corresponding to the propagation environment according to the propagation environment using the use restriction device By selecting the curve, it is possible to calculate the estimated separation distance more accurately.

  Next, the operation of the use restriction device according to Embodiment 1 will be described with reference to FIG.

  In step ST1001, the radio communication unit 100 transmits an identification code to the use restriction releasing unit 300. The identification code is transmitted at a predetermined cycle.

  In step ST1002 and step ST1003, when the use restriction releasing unit 300 succeeds in the authentication using the identification code, the use restriction releasing unit 300 transmits a confirmation signal to the wireless communication unit 100 using the carriers of two different frequencies f1 and f2.

  In step ST1004, the radio communication unit 100 measures the reception level corresponding to each frequency f1, f2 using the confirmation signal transmitted from the use restriction release unit 300, and transmits it to the use restriction release unit 300 as reception level information. To do.

  In step ST1005, use restriction cancellation unit 300 calculates a propagation loss corresponding to each frequency in separation distance calculation section 320.

In step ST1006, the separation distance calculation unit 320 determines whether or not the obtained propagation loss (f1) is equal to the propagation loss (f ₂ ).

As a result of the determination, when the propagation loss (f1) and the propagation loss (f ₂ ) are equal (step ST1006: YES), the separation distance calculation unit 320 stores an obstacle in the propagation path stored in the memory 330. The estimated separation distance is calculated based on the correspondence curve between the propagation loss and the separation distance when there is not and the obtained propagation loss values (step ST1007).

On the other hand, as a result of the determination, if the propagation loss (f1) and the propagation loss (f ₂ ) are not equal (step ST1006: NO), the separation distance calculation unit 320 stores f1, f2 stored in the memory 330. For each of these, a separation distance corresponding to each frequency is calculated from the corresponding curve between the propagation loss and the separation distance when there is an obstacle in the propagation path and the obtained propagation loss values (step ST1008). Since the propagation loss of the f1 higher frequency than the frequency f ₂ (f1) it can not be assumed to be less than the propagation loss (f _2), in this case, it is determined to have failed in the calculation of the propagation loss The current process may be terminated, and the process may be performed using the reception level information transmitted from the wireless communication unit 100 next time.

  In step ST1009, the separation distance calculation unit 320 calculates the estimated separation distance based on the separation distance obtained from each frequency.

  In step ST1010, the use restriction control unit 340 of the use restriction releasing unit 300 compares the estimated separation distance calculated by the separation distance calculation unit 320 in step ST1007 or step ST1009 with a threshold value.

  As a result of this comparison, when the estimated separation distance is equal to or greater than the threshold value (step ST1010: YES), the use restriction control unit 340 continuously outputs the use restriction release signal to the mobile terminal function control unit 210. Is stopped (step ST1011).

  On the other hand, if the estimated separation distance is less than the threshold value as a result of the comparison (step ST1010: NO), use restriction control section 340 continues to output the use restriction release signal (step ST1012).

  As described above, according to the first embodiment, the wireless authentication unit 110 that performs wireless authentication by transmitting / receiving a wireless signal to / from the wireless communication unit 100 to the mobile terminal device 200, and the estimation between the wireless authentication unit 110 Based on the separation distance, the use restriction control unit 340 that controls the use permission and the use restriction of the mounted function of the mobile terminal device 200, and the first frequency and the second frequency are transmitted at a constant intensity. A separation distance calculation unit 320 that calculates the estimated separation distance based on the reception level of the wireless signal.

  By doing so, the estimated separation distance is calculated based on the reception levels of the two different frequency carriers transmitted at a constant strength, and therefore the estimated separation distance closer to the actual separation distance can be calculated. Further, since it is possible to control the use permission and the use restriction of the mounted function based on the estimated separation distance closer to the actual separation distance, it is possible to prevent a malfunction that may occur due to an error between the actual separation distance and the estimated separation distance. As a result, the convenience of the owner and the like can be improved.

  The separation distance calculation unit 320 calculates a propagation loss value in the propagation path between both units when a radio signal is transmitted by the carrier of the first frequency and the second frequency, and calculates each propagation frequency from each propagation loss value. The estimated separation distance is calculated based on the separation distance between the corresponding units.

  By doing so, the estimated separation distance closer to the actual separation distance can be calculated using the tendency that the propagation loss changes according to the frequency when there is an obstacle in the propagation path. Further, since it is possible to control the use permission and the use restriction of the mounted function based on the estimated separation distance closer to the actual separation distance, it is possible to prevent a malfunction that may occur due to an error between the actual separation distance and the estimated separation distance. As a result, the convenience of the owner and the like can be improved.

  Furthermore, the mobile terminal device 200 has a propagation loss value and a separation distance between the radio communication unit 100 and the radio communication unit 100 according to a propagation environment between the radio communication unit 100 and each of the first frequency carrier and the second frequency carrier. Is stored in the memory 330, and the separation distance calculation unit 320, when the propagation loss related to the carrier of the first frequency coincides with the propagation loss related to the carrier of the second frequency, When the estimated separation distance is calculated using a corresponding curve when there is no obstacle in the propagation path between the two, the propagation loss related to the carrier of the first frequency does not match the propagation loss related to the carrier of the second frequency Calculates the separation distance based on the corresponding curve corresponding to the carrier of each frequency when there is an obstacle in the propagation path, and the separation distance Calculating the estimated distance based on.

  In the first embodiment, the transmission / reception unit 350 has been configured to generate carriers having a plurality of different frequencies using the plurality of frequency oscillators 380 and 390, but the single frequency oscillator is time-divisionally divided. It is also possible to employ a configuration in which a plurality of carriers having different frequencies are used. By adopting a configuration in which a single frequency oscillator is used in a time division manner, the number of parts of the mobile terminal device 200 can be reduced.

(Embodiment 2)
In the first embodiment, the use restriction releasing unit 300 transmits a confirmation signal to two different frequency carriers and transmits the confirmation signal to the radio communication unit 100, and receives the report of the reception level information measured by the radio communication unit 100. The restriction release unit 300 calculated the estimated separation distance. On the other hand, in the second embodiment, the reception level of the identification code transmitted by the wireless communication unit using the carrier of the first frequency and the second frequency different from the first frequency by the use restriction release unit The use restriction release unit calculates the estimated separation distance from the reception level at the wireless communication unit of the confirmation signal transmitted using the carrier.

As shown in FIG. 6, in radio communication unit 100 of the second embodiment, transmission / reception section 140 transmits an identification code using a carrier of frequency f ₂ generated by frequency oscillator 145.

  As illustrated in FIG. 7, the use restriction releasing unit 400 according to the second embodiment includes a transmission / reception unit 410, a wireless authentication control unit 420, and a reception signal level detection unit 430.

Reception signal level detection section 430 detects (measures) the reception level of the identification code transmitted from radio communication unit 100 using the carrier of frequency f ₂ , and outputs the reception level information to radio authentication control section 420.

The transmission / reception unit 410 transmits a confirmation signal using the carrier having the frequency f ₁ generated by the frequency oscillator 380.

  The wireless authentication control unit 420 performs authentication processing in the same manner as the wireless authentication control unit 360 of the first embodiment. Further, when the authentication is successful, the wireless authentication control unit 420 determines the reception distance information of the confirmation signal measured by the wireless communication unit 100 and the reception level information from the reception signal level detection unit 430 as the separation distance calculation unit 320. Output to.

  Next, the operation of the use restriction device of the second embodiment will be described with reference to FIG.

In step ST2001, using restriction release unit 400 measures the reception level of the identification code transmitted with the carrier frequency _{f 2} from the radio communication unit 100.

In step ST2002, a successful authentication using the identification code, use restriction release unit 400 transmits to the radio communication unit 100 by using the carrier frequency f ₁ of the confirmation signal.

In step ST2003, wireless communication unit 100 uses the confirmation signal sent from the use restriction release unit 400, a reception level corresponding to the frequency f ₁ is measured and transmitted to the use restriction release unit 400 as reception level information.

  In the above description, the case where the use restriction releasing unit 400 of the use restriction device is provided separately from the mobile terminal device 200 and used by being attached to the mobile terminal device 200 has been described. Instead, the portable terminal device 200 may have the use restriction releasing unit 400 mounted therein, that is, may be built therein.

  As described above, according to the second embodiment, each of the radio communication unit 100 and the use restriction releasing unit 400 transmits one of the radio signals of the two frequencies used for calculating the separation distance. It is possible to reduce a risk that a situation in which even the function for which the separation distance is calculated using the conventional single frequency cannot be exhibited due to the malfunction of the function will occur.

In the second embodiment, the identification code is transmitted using the carrier of frequency f ₂ generated by frequency oscillator 145 in radio communication unit 100, and the carrier of frequency f ₁ generated by frequency oscillator 380 in portable terminal device 200. Although the configuration for transmitting the confirmation signal using the above has been described, the configuration may be such that the frequency values of the frequency f ₁ and the frequency f ₂ generated by the respective frequency oscillators are changed at regular intervals, or alternately switched.

(Embodiment 3)
In the first embodiment, the use restriction releasing unit 300 transmits a confirmation signal to two different frequency carriers and transmits the confirmation signal to the radio communication unit 100, and receives the report of the reception level information measured by the radio communication unit 100. The restriction release unit 300 calculated the estimated separation distance. On the other hand, in the third embodiment, the use restriction cancellation unit calculates the estimated separation distance using the reception level of the identification code transmitted by the wireless communication unit using the first and second frequency carriers.

As shown in FIG. 9, the wireless communication unit 500 according to the third embodiment uses an identification code using carriers of _two different frequencies (f ₁ , f ₂ ) generated by the transmission / reception unit 510 in the frequency oscillator 520 and the frequency oscillator 530. Send.

  As shown in FIG. 10, the use restriction releasing unit 600 according to the third embodiment includes a wireless authentication control unit 610 and a received signal level detection unit 620.

Reception signal level detection section 620 detects (measures) the reception level of the identification code transmitted from radio communication unit 500 using the carriers of frequencies f ₁ and f ₂ , and outputs the reception level information to radio authentication control section 610. .

  The wireless authentication control unit 610 performs authentication processing in the same manner as the wireless authentication control unit 360 of the first embodiment. Further, when the authentication is successful, the wireless authentication control unit 610 outputs the reception level information from the reception signal level detection unit 620 to the separation distance calculation unit 320.

  Next, the operation of the use restriction device of the third embodiment will be described with reference to FIG.

In step ST3001 and step ST3002, radio communication unit 500 transmits the identification code to use restriction releasing unit 600 using the carriers of frequencies f ₁ and f ₂ .

In step ST3003, use restriction cancellation unit 600 measures the reception level of the identification code transmitted from radio communication unit 500 using the carriers of frequencies f ₁ and f ₂ .

  In step ST3004, when the authentication using the identification code is successful, the use restriction releasing unit 600 transmits a confirmation signal to the wireless communication unit 500.

In step ST1005, when the authentication using the identification code is successful, the use restriction releasing unit 600 calculates a propagation loss corresponding to each of the frequencies f ₁ and f ₂ from the reception level information measured in step ST3003.

  In the above description, the case where the use restriction canceling unit 600 of the use restriction device is provided separately from the mobile terminal device 200 and used by being attached to the mobile terminal device 200 has been described. Instead, the mobile terminal device 200 may have the use restriction releasing unit 600 mounted therein, that is, may include it.

  In the third embodiment, the transmission / reception unit 510 has been configured to generate carriers of a plurality of different frequencies using the plurality of frequency oscillators 520 and the frequency oscillator 530. However, a single frequency oscillator is time-shared. It is also possible to employ a configuration in which a plurality of carriers having different frequencies are used. By adopting a configuration in which a single frequency oscillator is used in a time division manner, the number of parts of the wireless communication unit 500 can be reduced.

(Other embodiments)
(1) In the first to third embodiments, the wireless authentication control unit 160 of the wireless communication units 100 and 500 uses the reception level information measured by the reception signal level detection unit 150 when authentication is successful. Based on this, the estimated separation distance is calculated, and when this estimated separation distance is equal to or greater than a predetermined threshold value, a signal is output to the alarm circuit 120. Reception of signals transmitted by carriers of two different frequencies measured by at least one of the wireless communication unit and the use restriction releasing unit as performed by the separation distance calculation unit 320 of the units 300, 400, and 600 The estimated separation distance may be calculated based on the level information.

  By doing so, the error between the actual separation distance and the estimated separation distance can be reduced, and an alarm can be issued to the user using the estimated separation distance that is closer to the actual separation distance. Can be prevented. Therefore, when the external output unit 130 is, for example, a speaker that emits sound, malfunctioning in a public place causes a great deal of trouble for others, and this can be prevented.

(2) In the first to third embodiments, when transmitting at least one of the identification code and the confirmation signal, the carrier of the two frequencies is used, and the estimated separation distance is determined using the reception level information at that time. Although the calculation is performed, the present invention is not limited to this, and a signal other than the identification code and the confirmation signal may be separately prepared and transmitted, and the estimated separation distance may be calculated using reception level information of this signal. .

(3) The portable terminal device and the authentication control method described in the first to third embodiments are also realized by a program for causing the portable terminal device and the authentication control method to function.

  INDUSTRIAL APPLICABILITY The portable terminal device and authentication control method of the present invention have the effect of improving the convenience of the owner and the like, and are useful when applied to a mobile phone, PDA, notebook computer, MP3 player, HDD player, and the like. .

The block diagram which shows the structure of the radio | wireless communication unit which concerns on Embodiment 1 of this invention. FIG. 3 is a block diagram showing the configuration of a use restriction releasing unit and a mobile terminal device according to the first embodiment. The figure which uses for description of the calculation method of the estimated separation distance in the separation distance calculation part of FIG. The figure which uses for description of the calculation method of the estimated separation distance in the separation distance calculation part of FIG. The figure which uses for description of a motion of the use restriction apparatus of Embodiment 1. FIG. 3 is a block diagram showing a configuration of a wireless communication unit according to the second embodiment. A block diagram showing configurations of a use restriction releasing unit and a mobile terminal device according to a second embodiment The figure which uses for description of a motion of the use restriction apparatus of Embodiment 2. FIG. 9 is a block diagram showing a configuration of a wireless communication unit according to the third embodiment. A block diagram showing configurations of a use restriction releasing unit and a mobile terminal device according to a third embodiment The figure which uses for description of a motion of the use restriction apparatus of Embodiment 3.

Explanation of symbols

100, 500 Wireless communication unit 110, 310 Wireless authentication unit 120 Alarm circuit 130 External output unit 140, 350, 410, 510 Transmission / reception unit 145, 380, 390, 520, 530 Frequency oscillator 150, 430, 620 Received signal level detection unit 160 360, 610 Wireless authentication control unit 170, 370 Authentication ID storage unit 200 Mobile terminal device 210 Mobile terminal function control unit 220 Transmission unit 230 Reception unit 300, 400, 600 Use restriction release unit 320 Separation distance calculation unit 330 Memory 340 Use Limit control part

Claims (5)

Wireless authentication means for performing wireless authentication by transmitting and receiving wireless signals to and from the wireless communication unit;
Use restriction means for controlling use permission and use restriction of the installed function based on the estimated separation distance from the wireless communication unit;
A separation distance calculating means for calculating the estimated separation distance based on a reception level of the radio signal transmitted at a constant intensity using carriers of the first frequency and the second frequency;
A portable terminal device comprising:   The separation distance calculating means calculates a propagation loss value in a propagation path between both units when the radio signal is transmitted by the carrier of the first frequency and the second frequency, and obtains from each propagation loss value The portable terminal device according to claim 1, wherein the estimated separation distance is calculated based on a separation distance between both units corresponding to each frequency. For each of the carriers of the first frequency and the second frequency, the correspondence relationship between the propagation loss value and the separation distance between the wireless communication units is stored according to the propagation environment with the wireless communication unit. Storage means for
The separation distance calculation means becomes an obstacle to the propagation path between the wireless communication unit and the propagation loss related to the carrier of the first frequency and the propagation loss related to the carrier of the second frequency coincide with each other. The estimated separation distance is calculated using the correspondence when there is nothing, and the propagation loss related to the carrier of the first frequency does not match the propagation loss related to the carrier of the second frequency. The radio according to claim 2, wherein each separation distance is calculated based on the correspondence relationship corresponding to a carrier of each frequency when there is an obstacle on the road, and the estimated separation distance is calculated based on the separation distance. Terminal device. An authentication control method for performing wireless authentication by transmitting and receiving a wireless signal between a wireless communication unit and a use restriction releasing unit in a mobile terminal device,
A calculation step of calculating an estimated separation distance between both units based on a reception level of the radio signal transmitted at a constant intensity using a carrier of a first frequency and a second frequency;
Based on the estimated separation distance, controlling the use permission and the use restriction of the mounted function of the mobile terminal device;
An authentication control method comprising: The calculating step calculates a propagation loss value in a propagation path between both units when the radio signal is transmitted by the carrier of the first frequency and the second frequency, and is obtained from each propagation loss value. Calculating the estimated separation distance based on a separation distance between both units corresponding to each frequency;
The authentication control method according to claim 4, further comprising:

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