JPH0984119A - Communication terminal equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain a communication control in accordance with distance between communication terminals by providing a distance judging means for judging terminal distance from and opposite party communication terminal equipment and a communication control means for controlling communication according to it. SOLUTION: This communication terminal equipment is provided with a distance judging part 3 for judging inter-terminal distance from the oppoisite party portable information terminal to be a communication opposite party and a communication control part 2 for controlling communication in accordance with distance judged by the distance judging part 3. Since distance between the terminals becomes clear by the distance judging part 3, the communication control part 2 controls not to execute communication when distance exceeds a certain fixed value, when a function consisting of distance and communication information quantity exceeds a certain fixed value and when the function consisting of remaining battery capacitance and the reciprocal of distance becomes less than the certain fixed value, for example, so that useless power consumption is prevented. Concerning information with high secrecy, the communication control part 2 executes communication only when distance between communication terminals is the fixed value and below, for example, so that wiretapping is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication terminal device suitable for application to, for example, a mobile phone, and more particularly to communication control according to a distance between terminals with a communication terminal device of a communication partner. A communication terminal device to perform.

[0002]

2. Description of the Related Art In recent years, there have been remarkable advances in communication technology, and among them, communication in which information is transmitted and received by wireless signals has attracted attention. As a method for realizing mutual communication between terminals using this wireless signal, there are a method of installing an exchange connection control station, a method of using a wireless LAN, and a method of using infrared rays.

A typical example of a method of installing a switching connection control station is a mobile phone. In mobile phones, a large number of base stations covering a certain area are installed, and users of mobile phones perform electric transmission via these base stations. However, a mobile phone has a problem in that it is vulnerable to eavesdropping because it transmits and receives a radio signal to and from a base station by radio waves. Therefore, it is necessary to scramble or encrypt the confidential information in advance so that it can be sniffed. However, since an encryption unit that performs such encryption is not suitable for carrying, it is often not attached to a mobile phone. Therefore, the mobile phone has a problem that it cannot transmit highly sensitive information. Further, in order to establish a communication connection, the base station needs to know the other party in advance, so the terminal needs to be registered. Therefore, it was not possible to connect with an unspecified number of other parties.

In the method using a wireless LAN, it is confirmed that no radio wave is present in a predetermined band (several 100 kHz to 10 MHz), and then information having a destination identification number is transmitted as a packet signal. A terminal within a range where a radio wave can reach is designed to take in the signal if its identification number is given to the received signal. Therefore, since it is necessary to know the identification number of the terminal in advance, it is not possible to connect with an unspecified number of parties.
In addition, since there is a risk that a radio wave will be eavesdropped, encryption or the like is required, which is unsuitable for transmitting and receiving confidential information.

In the method using infrared rays, information can be transmitted only between two mobile terminals. Further, since infrared rays cannot communicate when shielded, the transmitters and receivers of both terminals must be installed so as to face each other, which is a large physical limitation.

On the other hand, an invention which facilitates the transmission of information to an unspecified large number is described in JP-A-6-75757. In the present invention, all terminals capable of transmission / reception are set as a group, and information can be transmitted to this group. However, according to the present invention, although information can be easily transmitted to an unspecified number of people, it is not possible to transmit highly sensitive information to only a limited number of terminals. In addition, a large amount of electric power is required to uniformly transmit information to terminals capable of transmission and reception, and thus there is a problem that charging or battery replacement is required in a short cycle.

[0007]

In the future, it is conceivable that a large number of users will use a portable information device having a communication function in various situations. For example, when a child uses it and exchanges various information with nearby friends, it is desirable to transmit it as easily as possible. On the other hand, in a cram school or the like, when transmitting sensitive information such as grades between terminals of a teacher and a child, it is desirable to transmit only between specific terminals.

As described above, one portable information device needs to be able to transmit information to an unspecified number of times and to a specific terminal at some times, depending on the confidentiality of transmission.
On the other hand, in the conventional communication between portable information devices, it is necessary to register the identification number of the device of the communication partner in advance even for the communication of information intended to be transmitted to a large number, and it is transmitted to an unspecified large number. Couldn't be done easily.

Further, with respect to highly sensitive information, there have been problems such as a risk of eavesdropping on the transmission path, labor for setting encryption / decryption, and physical restrictions such as installation of terminals.
On the other hand, in the method aimed at transmitting information to the unspecified majority,
We could not send sensitive information only to a specific terminal.

When transmitting to an unspecified number of terminals,
If you transmit information to and from terminals that can send and receive,
Since the power consumption is large, it is necessary to frequently charge the battery.

The present invention has been made in view of such a situation, and when information is transmitted to an unspecified large number, for example, power is wastefully limited by limiting the terminals existing within a certain distance. An object of the present invention is to provide a portable information device that performs communication control according to the distance between terminals with a communication terminal device of a communication partner, such as preventing consumption.

Furthermore, the present invention provides communication control according to the distance between terminals with a communication terminal device of a communication partner, such as limiting the distance permitted for transmission according to the confidentiality of information to be transmitted. The purpose is to provide a portable information device that performs.

[0013]

According to the present invention, there is provided a communication terminal device for transmitting and receiving information by a radio signal, and a distance determining device for determining an inter-terminal distance to a communication terminal device of a communication partner. It is characterized by further comprising: communication control means for controlling communication with the communication terminal device of the other party according to the inter-terminal distance determined by the distance determination means.

Further, according to the present invention, in a communication terminal device for transmitting and receiving information by a radio signal, a distance judging means for judging a terminal distance to a communication terminal device of a communication partner, and the distance judging means. Communication control means for controlling communication with the communication terminal device of the other party based on the relationship between the determined inter-terminal distance and the confidentiality of transmission information to be transmitted to the communication terminal device of the other party. And

Further, the present invention further comprises an identifier holding means for holding an identifier indicating another communication terminal device permitted to transmit the confidential transmission information, and the communication control means retains the confidentiality. The communication terminal of the other party based on the comparison result between the identifier of the other party communication terminal to be the transmission target of the transmission information and the identifier held in the identifier holding means, and the relationship between the terminal distance and the secrecy level. It is characterized by controlling communication with the device.

Further, according to the present invention, in a communication terminal device configured to be capable of being driven by a battery and transmitting / receiving information by a radio signal, a distance determining means for determining an inter-terminal distance from a communication terminal device of a communication partner. And communication control means for controlling communication with the communication terminal device of the other party based on the relationship between the terminal distance determined by the distance determination means and the remaining capacity of the battery. .

Further, according to the present invention, in a wireless terminal device for transmitting / receiving information via a base station by a radio signal, a means for obtaining a base station to transmit / receive information, and a base station for transmitting / receiving obtained by this means, Distance determining means for determining the distance between the communication terminal devices to be transmitted / received based on the relationship with the base station to be transmitted / received by the communication terminal device of the communication partner, and the terminal determined by this distance determination means It is characterized by comprising a communication control means for controlling communication according to the distance between them.

According to the present invention, since the distance between the terminals is known by the distance determining means, the communication control means, when the distance exceeds a certain value, the function consisting of the distance and the communication information amount has a certain value. It is possible to prevent wasteful consumption of power by controlling not to perform communication when the value exceeds a certain value or when a function consisting of the remaining battery capacity and the reciprocal of the distance falls below a certain value. .

Further, with respect to information having a high confidentiality level, the communication control means can control the communication so that the communication is carried out only when the distance between the terminals is equal to or less than a predetermined value, thereby preventing eavesdropping.

Further, in the case of extremely sensitive information, the communication control means communicates only when the distance is within a certain range and the identification numbers of terminals that can access the information match. By controlling so that the information is transmitted only when the terminal permitted to access the information is within the predetermined range, it becomes easy to maintain the confidentiality of the information.

As for the distance between the communication terminal devices to be transmitted / received, the base station to / from which information is to be transmitted / received is calculated.
The determination can be made based on the relationship with the base station to be transmitted / received by the communication terminal device of the communication partner.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of a mobile information terminal according to an embodiment of the present invention. As shown in FIG. 1, the portable information terminal 9 of the embodiment includes an information processing unit 1 that executes various applications executed in the terminal,
A distance determination unit 3 that determines an inter-terminal distance between the mobile information terminal of the communication partner and a communication control unit 2 that performs communication control according to the distance determined by the distance determination unit 3 and an actual wireless communication device. The wireless transmission / reception unit 4 performs transmission / reception.

In the radio transmitter / receiver 4, the frequency of the signal sent from the communication controller 2 is converted to a high frequency by the multiplier 41, and the appropriate power is amplified by the power amplifier 42. It is transmitted from the antenna 45 via 43.

On the other hand, each information signal received by the antenna 45 from another portable information terminal is sent to the down-converting unit 44 via the demultiplexer 43, and the down-converting unit 44 converts the high frequency into the baseband band. After that, it is sent to the communication control unit 2. The wireless transmission / reception unit 4 can also be realized by incorporating a small PHS (personal handset) or the like.

An example of calculation of the distance between portable information terminals will be described with reference to FIG. In addition, here, consider a case where wireless transmission / reception is performed using PHS. First, if the portable information terminal can receive information signals from three base stations, the location can be specified (FIG. 2 (a)).

Further, as shown in FIG. 2 (b), when the signals can be received from two base stations, for example, the portable information terminal a is in the shaded area 51 and the portable information terminal b is in the shaded area 52.
The existence of each can be confirmed. In this case, for example, the average of the shortest distance and the longest distance between the two areas is used as the distance between the mobile information terminal a and the mobile information terminal b.

On the other hand, if either one is receiving from only one base station, the existence of each can be confirmed in the area as shown in FIG. 2 (c). The intermediate value between the maximum distance and the maximum distance is the distance between the two mobile information terminals.

When both units are receiving from only one base station, the result is as shown in FIG. 2 (d), which is also the same as that described above, and the intermediate value between the shortest distance and the longest distance is set to two units. The distance to the terminal.

For example, when it is used in a business office, the setting range of the base station is about 30 to 50 m, so that the distance can be sufficiently estimated by this method. On the other hand, it is also possible to measure the position of each mobile information terminal by using GPS (Global Positioning System) widely used in car navigation and the like. In the case of a car,
Because it is moving fast, it must receive four waves from the satellite to establish the four variables of latitude, longitude, height, and time. However, in the case of a mobile information terminal, it is only necessary to be able to determine the latitude and longitude, so it is sufficient to be able to receive two waves. Since the latitude and longitude of each portable information terminal can be measured by GPS, the distance can be calculated from this.

Communication control in the communication control unit 2 is performed as follows. In the first control method, first, a boundary distance (k) is set in advance so that signals will not be transmitted / received if it exceeds the limit. The simplest control is to compare the calculated distance (d) of the distance determination unit 4 and the previous boundary distance (k), and if d ≦ k ... (1), transmit and receive.

The second control method also incorporates the remaining battery level in order to reduce power consumption. A function F (d, p) of the distance (d) and the remaining battery charge ratio p is set, and when the value becomes lower than a certain value, transmission / reception is performed.

As the functional form, the simplest form such as F (d, p) = d / p (2) can be considered.

Alternatively, as in F (d, p) =-d log p (3), it is possible to prevent information from being transmitted and received exponentially with respect to the remaining battery level.

Regarding reception, there is a non-stop reception such as a character broadcast in the FM broadcast band. With respect to these, it is possible to perform control such that the battery is saved by limiting the reception of the frequency band of the FM broadcast according to the battery remaining amount (p).

The third control method is to use the condition of any of the above equations (1) to (3) for reception and to perform control according to the amount of information for transmission. . That is, assuming that the amount of information to be transmitted is (q) bits, a function G (d, of the distance (d) and the amount of information (q)
q) is set and the value becomes lower than a certain value,
It is to send.

As the functional form, G (d, q) = dq (4) or G (d, q) = d log q (5) can be considered.

Further, when transmitting a long distance by radio, there is a possibility that information may be intercepted on the way. Therefore, the fourth
As a control method of (1), information having a high level of confidentiality is controlled so as not to transmit a long distance. Specifically, when the secrecy is the highest, the distance between the two terminals is almost zero, and for the next highest secrecy, the distance is k1,
The general information is that the distance is k2, for example, instead of equation (1), d ≦ 0 (for the highest confidentiality), d <k1 (for the medium confidentiality), d <k2 ( In the case of general information) It is also possible to use equation (6) such as (6).

When the confidentiality is the highest, the communication control unit 2 verifies whether or not the identification number of the receiving terminal matches the identification number that can access the highly confidential information. Is transmitted, and if they do not match, control such as not transmitting even if the distance is 0 is also effective.

Next, the operation procedure of the mobile phone of the embodiment will be described with reference to FIGS. FIG. 3 is a flowchart showing an operation procedure when performing communication control based on the distance between terminals and the confidentiality of information.

First, the distance determination unit 3 calculates the distance to the partner terminal (step A1). Next, the communication control unit 2
The sensitivity of information is judged (step A2), and step A1
It is determined whether or not the distance to the partner terminal obtained in step S2 is within the range of the communication permission distance set according to the confidentiality (step A3, step A4, step A5).

Then, the communication control unit 2 controls so that the information is transmitted when the distance to the partner terminal is within the range of the distance permitted for communication set according to the secrecy level ( Step A6).

FIG. 4 is a flow chart showing an operation procedure for performing communication control based on the distance between terminals, the remaining amount of battery and the amount of information to be transmitted. First, the communication control unit 2 calculates the remaining battery level (step B1). Further, the distance determination unit 3 calculates the distance to the partner terminal (step B
2). Then, the communication control unit 2 calculates the amount of information to be transmitted (step B3).

Here, the communication control unit 2 determines whether or not the value of the function F (d, p) of the distance (d) and the ratio p of the remaining battery level is lower than a certain fixed value (step B4). ). If this value is greater than or equal to a certain value (step B4
N), the process ends without transmitting. On the other hand, when the value is lower than a certain value (Y in step B4), the communication control unit 2 has the value of the function G (d, q) of the distance (d) and the information amount (q). It is determined whether it is lower than a certain value (step B5).

If this value is equal to or greater than a certain value (N in step B5), the process is terminated without transmitting. On the other hand, when the value is lower than the certain value (Y in step B5), the communication control unit 2 controls to transmit the information (step B6).

FIGS. 5 and 6 are flowcharts showing an operation procedure for performing communication control based on the distance between terminals, the confidentiality of information, the remaining amount of battery and the amount of information to be transmitted. First, the communication control unit 2 calculates the remaining battery level (step C1). Further, the distance determination unit 3 calculates the distance to the partner terminal (step C2). Then, the communication control unit 2 calculates the amount of information to be transmitted (step C3).

Next, the communication control unit 2 judges the secrecy of the information (step C4), and the distance to the partner terminal obtained in step C2 is the distance which permits communication set according to the secrecy. It is determined whether or not it is within the range (step C
5, step C6, step C7).

Then, the communication control unit 2 terminates the processing without transmitting when the distance to the partner terminal is out of the range of the communication permission distance set according to the secrecy level. On the other hand, when the distance to the partner terminal is within the range of the distance that allows communication, which is set according to the secrecy, the communication control unit 2 determines that the distance (d) is the ratio of the remaining battery level (p).
It is determined whether or not the value of the function F (d, p) of and is lower than a certain fixed value (step C8). If this value is greater than or equal to a certain value (N in step C8), the process is terminated without transmitting. On the other hand, when the value is lower than a certain value (Y in step C8), the communication control unit 2
It is determined whether or not the value of the function G (d, q) of the distance (d) and the information amount (q) is lower than a certain constant value (step C
9).

If this value is equal to or greater than a certain value (N in step C9), the process is terminated without transmitting. On the other hand, when the value is lower than the certain value (Y in step C9), the communication control unit 2 controls to transmit the information (step C10).

As a result, security protection according to the distance between terminals and battery residual amount management according to the distance between terminals can be realized. It should be noted that in the same embodiment, the distance determination is PH
Although the relationship between S and the base station or the method of calculating by GPS has been shown, the present invention is not necessarily limited to this. For example, a method is possible in which the time of transmission is added to the information to be transmitted and transmitted, and the receiving side calculates the distance from the time difference (delay). As described above, the distance determination method can be modified in various ways.

The control method based on the distance is not limited to the method shown in the embodiment. In the embodiment, the same determination condition is used for transmission and reception, but since transmission consumes more power than reception, the transmission is subjected to a stricter condition than reception (for example, a shorter distance). It is also possible. That is, instead of equation (1), the reception boundary distance k1 and the transmission boundary distance k2 (k2 <k
It is also possible to use 1) to receive when d <k1 ... (7) and transmit when d <k2 ... (8).

Further, since the transmission power and the constant transmission speed are in a proportional relationship, there is a certain condition of transmission (equations (1), (2), (3),
When (4), (5) and (8) are not satisfied, it is possible to control so as to realize transmission by a method of saving transmission power by halving the transmission rate.

[0052]

As described above in detail, according to the present invention, since the transmission / reception can be controlled according to the distance, the power consumed for the transmission / reception can be saved. In particular, text broadcasts in the FM broadcast band are constantly being spilled, so when the battery is almost discharged, it is possible not to receive it, so prevent important information from being missed. You can

Further, since it is possible to control the distance that can be transmitted in accordance with the confidentiality level, it is possible to prevent information with high confidentiality level from being transmitted only to a mobile information terminal in a very close vicinity, thereby providing an opportunity for information tapping. Can be greatly reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a mobile information terminal according to an embodiment of the present invention.

FIG. 2 is an exemplary view showing a positional relationship between the portable information terminal and the base station of the same embodiment.

FIG. 3 is an exemplary flowchart showing an operation procedure when performing communication control based on a distance between terminals and confidentiality of information according to the first embodiment.

FIG. 4 is an exemplary flowchart showing an operation procedure when performing communication control based on a distance between terminals, a battery remaining amount, and an amount of information to be transmitted according to the first embodiment.

FIG. 5 is a distance between terminals according to the first embodiment, a sensitivity of information,
The flowchart which shows the operation procedure at the time of performing communication control from a battery remaining amount and the amount of information to transmit.

FIG. 6 is a diagram illustrating a distance between terminals and confidentiality of information according to the embodiment.
The flowchart which shows the operation procedure at the time of performing communication control from a battery remaining amount and the amount of information to transmit.

[Explanation of symbols]

1 ... Information processing unit, 2 ... Communication control unit, 3 ... Distance determination unit, 4
... wireless transmission / reception section, 9 ... portable information terminal, 41 ... multiplication section, 4
2 ... Power amplification part, 43 ... Divider, 44 ... Reduction part, 45 ...
antenna.

Claims (5)

[Claims] 1. In a communication terminal device for transmitting and receiving information by a wireless signal, a distance judging means for judging an inter-terminal distance between the communication terminal device of a communication partner and a terminal judged by the distance judging device. A communication terminal device, comprising: communication control means for controlling communication with the communication terminal device of the other party according to the distance. 2. A communication terminal device for transmitting and receiving information by a wireless signal, a distance determining device for determining an inter-terminal distance between a communication partner device of a communication partner and a terminal determined by the distance determining device. A communication terminal, comprising: communication control means for controlling communication with the communication terminal device of the other party based on the relationship between the distance and the confidentiality of transmission information to be transmitted to the communication terminal device of the other party. apparatus. 3. The communication control means further comprises an identifier holding unit for holding an identifier indicating another communication terminal device permitted to transmit the confidential transmission information, wherein the communication control unit stores the confidential transmission information. Communication with the communication terminal device of the other party based on the result of comparison between the identifier of the other party communication terminal to be transmitted and the identifier held in the identifier holding means, and the relationship between the terminal distance and the confidentiality level. The communication terminal device according to claim 2, wherein 4. A communication terminal device configured to be battery-operable and transmitting / receiving information by a radio signal, and a distance determining means for determining an inter-terminal distance between the communication terminal device and a communication partner device as a communication partner, and this distance. A communication terminal device, comprising: a communication control device that controls communication with the other communication terminal device based on the relationship between the terminal distance determined by the determination device and the remaining capacity of the battery. 5. A wireless terminal device for transmitting / receiving information via a base station by a wireless signal, means for obtaining a base station for transmitting / receiving information, base station for transmitting / receiving obtained by this means, and a communication partner. Based on the relationship with the base station to be transmitted / received by the other communication terminal device, the distance determination means for determining the distance between the communication terminal devices to be transmitted / received, and the distance between the terminals determined by this distance determination means And a communication control unit that controls communication according to the communication terminal unit.