JP4285696B2 - Mobile communication terminal - Google Patents

Description

  The present invention relates to a portable communication terminal that has a wireless communication function such as a mobile phone or a PDA (Personal Digital Assistance) and is portable.

  In recent years, portable portable communication terminals having wireless communication functions such as mobile phones and PDAs have become widespread, and while downsizing of devices for improving portability has been promoted, in order to increase convenience Various functions are being developed. For example, when you use a mobile communication device, you can detect the user ’s usage status and operation status, such as when the user has the device or the user is on a call. A touch sensor or the like for performing an operation according to the situation has been developed (see, for example, Patent Document 1).

Patent Document 1 discloses a function of detecting the presence or absence of a human body contact with a mobile communication terminal using a touch sensor and reducing the volume of a ringtone according to the detection by the touch sensor. According to the function disclosed in Patent Document 1, the volume of the ringtone is reduced according to the detection by the touch sensor, so that the user is in a state of holding the mobile communication terminal and immediately responds to the incoming call. When possible, it is possible to avoid ringing the ringer at a volume higher than necessary.
Japanese Patent Laid-Open No. 9-238376

  However, conventionally, mobile communication terminals have to be equipped with devices necessary for maintaining communication functions such as antennas, and the size of liquid crystal displays has been increased in order to meet the demands for operability and multi-functionality. While the number of buttons and keys is increasing, there is a demand for downsizing of the device, and it is difficult to secure a space for arranging the touch sensor as described above.

  The present invention has been made to solve the above-mentioned problems, and while realizing downsizing of a mobile communication terminal, various functions are added by providing a touch sensor to improve operability and convenience. It is an object of the present invention to provide a portable communication terminal that can be used.

In order to solve the above-described problem, a mobile communication terminal according to the present invention is arranged on a surface of a casing of the mobile communication terminal, and a plurality of radiation conductors for transmitting and receiving radio signals, and a surface of the casing of the mobile communication terminal. Based on a change in electrical resistance between the radiating conductor and the ground electrode, which is changed when a human body contacts the radiating conductor and the ground electrode, the radiating conductor and the radiating conductor A resistance detection unit that detects the presence or absence of contact of the human body with the ground electrode, and a radio wave with respect to a radiation conductor that does not change the electrical resistance among the plurality of radiation conductors according to a detection result by the resistance detection unit. A transmission / reception unit for inputting and outputting signals. According to the present invention as described above, the antenna that transmits and receives radio waves and the touch sensor that detects contact of the human body can be used together by the radiation conductor, and space saving on the surface of the housing can be achieved. In addition, it is possible to use a radiation conductor that is not in contact with the human body as an antenna, and it is possible to prevent the sensitivity of the antenna from being lowered due to contact with the human body. As a result, for example, an appropriate antenna can be selected according to how the user's terminal is held and the posture during a call, and radio wave transmission / reception according to the use state of the user can be realized.

Moreover, in order to solve the above-mentioned problem, the mobile communication terminal according to the present invention is arranged on the surface of the casing of the mobile communication terminal, and a plurality of radiation conductors for transmitting and receiving radio signals, and the casing of the mobile communication terminal Based on a change in electrical resistance between the radiation conductor and the ground electrode, which changes when a human body comes into contact with the ground electrode and the radiation conductor and the ground electrode. And a resistance detection unit for detecting the presence or absence of human contact with the ground electrode, and based on the detection result by the resistance detection unit, the circuit constant for the radiation conductor is changed to a matching constant corresponding to the degree of change in the electrical resistance. A matching constant switching circuit for switching. According to the present invention as described above, the antenna that transmits and receives radio waves and the touch sensor that detects contact of the human body can be used together by the radiation conductor, and space saving on the surface of the housing can be achieved. Further, it is possible to appropriately select and use an appropriate matching constant according to a change in radio wave environment due to contact with the human body, and it is possible to prevent the antenna sensitivity from being lowered due to contact with the human body. Note that the matching constants can be switched by switching circuits with different matching constants or by using a variable matching circuit.

In order to solve the above-described problem, a mobile communication terminal according to the present invention is arranged on the surface of a casing of the mobile communication terminal, and a radio conductor for transmitting and receiving radio signals, and a radio signal for the radio conductor. A transmission / reception unit that performs input / output, a ground electrode disposed on a housing surface of the mobile communication terminal, and the radiation conductor and the ground electrode that change when a human body contacts the radiation conductor and the ground electrode A resistance detection unit that detects the presence or absence of contact of the human body with the radiation conductor and the ground electrode based on a change in electrical resistance between and a predetermined display or sound according to a detection result by the resistance detection unit. And an output unit that performs output. As a result, the antenna for transmitting and receiving radio waves and the touch sensor for detecting contact with the human body can be used as the radiation conductor, and space saving on the surface of the housing can be achieved. In addition, functions such as detecting that the user has a terminal, turning on the LED or outputting sound in response to changes in the user's usage status, and enabling communication according to the user's usage status. This can be realized while saving space on the surface of the housing.

Further, in order to solve the above-described problem, the mobile communication terminal according to the present invention is provided with a plurality of the radiation conductors, and the output unit corresponds to the radiation conductor in which a change in electrical resistance occurs and the generated electrical resistance value. Different outputs. As described above , more various communication can be achieved by performing different outputs depending on the location where the user touches.

The mobile communication terminal according to the present invention has a wireless communication function such as a mobile phone and a PDA and is portable and adds various functions by providing a touch sensor while realizing downsizing of the device. The operability and convenience can be improved.

[First Embodiment]
(Configuration of mobile communication terminal)
Embodiments of the present invention will be described with reference to the drawings. 1A and 1B are explanatory diagrams showing a mobile communication terminal according to the present embodiment, in which FIG. 1A is an external view and FIG. 1B is an external view in a use state.

  The mobile communication terminal 1 according to the present embodiment is a communication terminal device such as a mobile computer having a communication function such as a PDA, a mobile phone having a communication function such as a PDA, and a mobile phone such as a fixed phone, as well as a mobile communication terminal such as a mobile phone and a PHS. A general user interface such as a display display and operation buttons is arranged on the surface of the communication terminal 1 (not shown).

  In particular, on the surface of the housing 1a according to the present embodiment, as shown in FIG. 1A, a radiation conductor 2 for transmitting and receiving radio signals and an electrical connection to the radiation conductor 2 inside the housing 1a are provided. The ground electrode 3 is provided. The radiation conductor 2 and the ground electrode 3 are insulative on the surface of the housing 1a, and are spaced apart by a distance of about 2 cm to 8 cm. As shown in FIG. When a human body such as a user's hand comes into contact with each other, it is electrically connected with the electrical resistance of the human body.

  FIG. 2 is a block diagram and a circuit diagram showing the internal configuration of the mobile communication terminal 1. As shown in FIG. 2A, the mobile communication terminal 1 causes the radiation conductor 2 to function as an antenna, and also serves as an antenna / sensor circuit 11 for functioning as a touch sensor for detecting contact with the human body. An RF circuit 4 that is a transmission / reception unit for inputting / outputting radio signals to / from the radiation conductor 2 through the antenna / sensor circuit 11 and a resistance detection means for detecting a change in electrical resistance between the radiation conductor 2 and the ground electrode 3. And a detection terminal Vsense.

  At normal time (when the human body is in a non-contact state), the antenna / sensor circuit 11 receives power from the RF circuit 4 to the power supply unit 12 as shown in FIG. Through 12, transmission power for radio wave transmission is supplied to the radiation conductor 2. In this normal time, a voltage from the bias power source Vdd is applied between the radiation conductor 2 and the ground electrode 3 as a power source for the touch sensor.

  The voltage from these two power sources is adjusted by the antenna matching elements L1 and L2 and the choke coil L3, the resistance by the bias resistor R1, and the mutual influences are offset by the DC blocking capacitors C1 and C2. The transmission / reception of radio waves by the radiation conductor 2 does not affect the output from the detection terminal Vsense. At this time, that is, L1 and L2 are circuit elements for antenna matching, and are adjusted to optimize the radiation characteristics of the radiation conductor 2. The bias resistor R1 is set sufficiently larger than the resistance value of the human body. With such a circuit, since R1 has a very large resistance value under normal conditions, the current from Vdd does not flow, and a voltage substantially the same as Vdd is applied to the detection terminal Vsense.

  When the human body is in contact with the radiation conductor 2 and the ground electrode 3 as shown in FIG. 1 (b), the radiation conductor 2 and the ground electrode 3 are shown in FIG. 2 (c). Are short-circuited with an equivalent resistance value R2 by the human body, and the output value from the detection terminal Vsense changes. That is, when the radiation conductor 2 and the ground electrode 3 are short-circuited due to contact with a human body or the like, the connection is equivalently made with a resistance value of R2, and a current flows between the radiation conductor 2 and the ground electrode 3, The voltage at the detection terminal Vsense is lowered to a value close to 0V. At this time, since R1 and L3 have very large impedance values, the antenna circuit to which the power supply unit 12 belongs and the sensor circuit to which the bias power supply Vdd belongs are separated and operate independently.

  The detection terminal Vsense is a terminal that outputs the voltage of the bias power source Vdd that is divided into the bias resistor R1 and the resistance R2 by the human body, and is divided by contact of the human body to detect a decrease in output from the detection terminal Vsense. By doing so, the contact of the human body can be detected. The detection terminal Vsense can be connected to an antenna selection circuit or an LED lighting control circuit, for example, as in an embodiment described later, thereby enabling various functions according to the contact of the human body to be operated. Become.

(Operation and effect of mobile communication terminal)
According to the mobile communication terminal 1 according to the present embodiment having such a configuration, the antenna that transmits and receives radio waves and the touch sensor that detects contact with the human body can be used together by the radiation conductor 2, and the housing Space saving on the surface of 1a can be achieved, and various functions of the touch sensor can be added while improving the operability and convenience while realizing miniaturization of the portable communication terminal.

(Example of change)
As the circuit configuration of the antenna / sensor circuit 11 described above, the one shown in FIG. 3 can also be employed. That is, as shown in FIG. 5A, an FET circuit 13 can be provided as an output circuit of the detection terminal Vsense, and the output of the detection terminal Vsense can be made binary or stepwise. As a result, as shown in FIG. 5B, when the radiation conductor 2 and the ground electrode 3 are short-circuited with a resistance value R2 due to contact with the human body, only when a resistance value R2 exceeding a predetermined threshold value occurs. The output value of the detection terminal Vsense can be changed. As a result, it is possible to prevent the output of the detection terminal Vsense from steplessly changing due to the difference in the constitution of the contacted human body, the way of touching, the temperature and the humidity, and an accurate operation can be ensured.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. FIG. 4 is an explanatory diagram showing the mobile communication terminal 1 according to the present embodiment, in which (a) is an external view, (b) is a functional block diagram, and (c) is a side view of a modified example. .

  This embodiment is characterized in that a plurality of radiation conductors 2 described in the first embodiment are provided as shown in FIG. More specifically, in the present embodiment, two radiation conductors 21 and 22 are arranged on the upper left and right of the mobile communication terminal 1, and the ground electrode 3 is provided in the lower center. Similar to the first embodiment described above, these are insulated on the surface of the housing 1a and spaced apart by a distance of about 2 cm to 8 cm.

  As shown in FIG. 2B, antenna and sensor circuits 11a and 11b are provided for the radiation conductors 21 and 22, respectively. The antenna / sensor circuits 11a and 11b are connected so that the ground electrode 3 is shared.

  The detection terminals Vsense1 and Vsense2 of each antenna and sensor circuit 11a and 11b are connected to the antenna selection circuit 6. The antenna selection circuit 6 compares the outputs from the detection terminals Vsense1 and Vsense2, detects a radiation conductor in which no change in electrical resistance occurs, that is, a radiation conductor that is not in contact with the human body, and detects the detected radiation conductor. Is a circuit that outputs a switching control signal for switching the radiation conductor to the antenna selector switch 5 in order to input / output radio signals. The antenna changeover switch 5 is a circuit that selectively connects the RF circuit 4 and the antenna / sensor circuit 11a or 11b based on a switching control signal from the antenna selection circuit 6.

  According to such a portable communication terminal 1 according to the second embodiment, it is possible to appropriately select a radiation conductor that is not in contact with the human body and use it as an antenna, and the sensitivity of the antenna is reduced by contact with the human body. Can be prevented.

  In the present embodiment, the two radiation conductors 21 and 22 are arranged on the upper left and right sides of the mobile communication terminal 1 and the ground electrode 3 is provided at the lower center thereof. For example, as shown in FIG. The radiation conductors 21 and 22 may be disposed at both upper and lower ends of the housing 1a, and the ground electrode 3 may be disposed at the center. In this case, it is possible to select an appropriate antenna according to how the user's terminal is held during a call, for example, with the upper part of the terminal and with the lower part of the terminal. Radio wave transmission / reception can be realized.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. FIG. 5 is a functional block diagram of the mobile communication terminal 1 according to the present embodiment.

  In the second embodiment described above, a plurality of radiation conductors 2 are switched and used as an antenna. However, in this embodiment, a single radiation conductor is provided, a plurality of matching circuits for the radiation conductor are provided, and the output from the detection terminal Vsense is changed. Switch the matching circuit. Specifically, a plurality of matching circuits having different matching constants are provided in the antenna / sensor circuit 11, and a matching circuit changeover switch 11 c is provided for switching and selectively connecting to the RF circuit 4. In response to the switching control signal from 7, the matching circuit is switched.

  The antenna matching selection circuit 7 monitors the output from the detection terminal Vsense, detects the degree of change in electrical resistance, and outputs a switching control signal for switching to a matching circuit according to the detected degree of change. 14 is a circuit that outputs the signal. The matching circuit changeover switch 14 is a circuit that selectively connects the RF circuit 4 and one of a plurality of matching circuits based on a switching control signal from the antenna matching selection circuit 7.

  According to the mobile communication terminal 1 according to the third embodiment, it is possible to appropriately select and use a matching circuit having an appropriate matching constant according to a change in radio wave environment due to contact with the human body. Therefore, it is possible to prevent the antenna sensitivity from being lowered.

  In this embodiment, a plurality of matching circuits having different matching constants are provided and switched to perform matching. For example, instead of a plurality of matching circuits, a variable matching circuit having a variable matching constant is provided, and the human body It may be possible to adjust to an appropriate matching constant according to a change in the radio wave environment due to contact.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described. FIG. 6 is a functional block diagram of the mobile communication terminal 1 according to the present embodiment.

  The present embodiment is characterized in that an LED lighting control circuit 8 that performs a predetermined output display is provided in accordance with the detection output from the detection terminal Vsense in each of the above-described embodiments. Specifically, the detection terminal Vsense of the antenna and sensor circuit 11 is connected to the LED lighting control circuit 8 as shown in FIG. This LED lighting control circuit 8 monitors the change in the output from the detection terminal Vsense, and when the change in electrical resistance between the radiation conductor 2 and the ground electrode 3 occurs, that is, when the human body comes into contact, the LED 81 is controlled. It is a circuit to be lit.

  According to the present embodiment, the LED 81 can be turned on in accordance with a change in usage state such as when the user has the mobile communication terminal 1. As a result, for example, a function for communicating with the user, such as notification or warning of the usage state of the user, can be realized while saving the space on the surface of the housing 1a.

  As a modification of the present embodiment, as shown in FIG. 6B, a plurality of radiation conductors are provided, and the LED lighting control circuit 8 includes a radiation conductor in which a change in electrical resistance has occurred, and an electrical resistance that has occurred. Different LEDs 81 can be lit depending on the value.

  Specifically, a plurality of radiation conductors 21 and 22 and antenna / sensor circuits 11a and 11b for the radiation conductors 21 and 22 are provided, and LED lighting control is performed on the detection terminals Vsense1 and Vsense2 from the antenna / sensor circuits 11a and 11b. Connect to circuit 8. The LED lighting control circuit 8 monitors changes in the outputs from the detection terminals Vsense1 and Vsense2, and when a change in the electrical resistance between the radiation conductor 21 or 22 and the ground electrode 3 occurs, the radiation conductor in contact with the human body is applied. In response, the LED 81 is turned on. In this case, more various communications can be achieved by turning on different LEDs according to the location where the user touches.

  In the embodiment and the modification described above, lighting of the LED is adopted as a means for outputting and displaying, but the present invention is not limited to this, for example, displaying a message on a liquid crystal display, outputting a sound, Various output means such as turning on the backlight of the liquid crystal display can be employed. Further, for example, a clock function is provided in the LED lighting control circuit 8 so that the LED lighting method, the message to be displayed, the voice to be output, the illuminance of the backlight, etc. are changed according to the time when the user touches the portable terminal. It may be.

It is explanatory drawing which shows the portable communication terminal which concerns on 1st Embodiment, (a) is an external view, (b) is an external view in use condition. (A) is a block diagram which shows the internal structure of the portable communication terminal which concerns on 1st Embodiment, (b) is a circuit diagram of an antenna and sensor circuit, (c) is an antenna and antenna in the state which the human body contacted It is a circuit diagram of a sensor circuit. (A) is a circuit diagram of the antenna and sensor circuit which concerns on the example of a change in 1st Embodiment, (b) is a circuit diagram of the antenna and sensor circuit in the state which the human body contacted. It is explanatory drawing which shows the mobile communication terminal 1 which concerns on 2nd Embodiment, (a) is an external view, (b) is a functional block diagram, (c) is a side view of the example of a change. It is a functional block diagram of the portable communication terminal 1 which concerns on 3rd Embodiment. It is a functional block diagram of the mobile communication terminal 1 which concerns on 4th Embodiment.

Explanation of symbols

C1, C2 DC blocking capacitor, L1, L2 antenna matching element, L3 choke coil, R1 bias resistance, R2 equivalent resistance value due to human contact, Vdd bias power supply, Vsense, Vsense1, Vsense2 detection terminal, 1 mobile communication terminal DESCRIPTION OF SYMBOLS 1a Case, 2 Radiation conductor, 3 Ground electrode, 4 RF circuit, 5 Antenna changeover switch, 6 Antenna selection circuit, 7 Antenna matching selection circuit, 8 LED lighting control circuit, 11, 11a, 11b Antenna and sensor circuit, 12 Power supply unit, 13 FET circuit, 14 matching circuit selector switch, 21, 22 radiation conductor, 81 LED

Claims (4)

A plurality of radiating conductors arranged on the surface of the casing of the mobile communication terminal for transmitting and receiving radio signals ;
A ground electrode disposed on a surface of the casing of the mobile communication terminal;
Based on the change in electrical resistance between the radiation conductor and the ground electrode, which changes as the human body contacts the radiation conductor and the ground electrode, the contact of the human body with the radiation conductor and the ground electrode is changed. A resistance detector for detecting presence or absence;
A transmission / reception unit for inputting / outputting radio signals to / from a radiation conductor in which no change in electrical resistance occurs among the plurality of radiation conductors according to a detection result by the resistance detection unit;
A mobile communication terminal. A radiation conductor disposed on the surface of the casing of the mobile communication terminal for transmitting and receiving radio signals;
A transmission / reception unit for inputting / outputting radio signals to / from the radiation conductor;
A ground electrode disposed on a surface of the casing of the mobile communication terminal;
Based on the change in electrical resistance between the radiation conductor and the ground electrode, which changes as the human body contacts the radiation conductor and the ground electrode, the contact of the human body with the radiation conductor and the ground electrode is changed. A resistance detector for detecting presence or absence;
A matching constant switching circuit that switches a circuit constant for the radiation conductor to a matching constant according to the degree of change in the electrical resistance based on a detection result by the resistance detection unit ;
A mobile communication terminal. A radiation conductor disposed on the surface of the casing of the mobile communication terminal for transmitting and receiving radio signals;
A transmission / reception unit for inputting / outputting radio signals to / from the radiation conductor;
A ground electrode disposed on a surface of the casing of the mobile communication terminal;
Based on the change in electrical resistance between the radiation conductor and the ground electrode, which changes as the human body contacts the radiation conductor and the ground electrode, the contact of the human body with the radiation conductor and the ground electrode is changed. A resistance detector for detecting presence or absence;
An output unit for outputting a predetermined display or sound according to a detection result by the resistance detection unit;
A mobile communication terminal. A plurality of the radiation conductors are provided,
The output unit performs different outputs depending on the radiation conductor in which the change in electric resistance occurs and the generated electric resistance value.
The mobile communication terminal according to claim 3.

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