JP4488218B2 - Portable wireless device and wireless communication method - Google Patents

Description

  The present invention relates to a portable wireless device such as a cellular phone, and more particularly to a technique for stabilizing a wireless transmission / reception operation.

  There are two types of antennas for portable wireless devices such as cellular phones: an exposed type that can project from the case and a built-in type that is built into the case.

  In general, the exposed type is superior to the built-in type in terms of transmission / reception sensitivity when projected from the housing. On the other hand, the built-in type may be inferior in transmission / reception sensitivity compared to the projecting type, but it does not have a convex part on the surface of the housing, contributing to the portability of the portable wireless device and eliminating the need for the user to project / store. Therefore, it contributes to operability, and since no convex portion is formed on the surface of the housing, it is possible to bring out a sense of unity of the apparatus and bring about a design effect.

  However, it is difficult for the user to specify the position where the built-in antenna is built simply by looking at the appearance of the housing. For this reason, when using the portable wireless device, the user may unintentionally cover the built-in antenna with his hand, or may unconsciously cause the built-in antenna to approach the metal. In such a case, the gain of the built-in antenna is lowered, and there is a possibility that the wireless transmission / reception operation by the portable wireless device may be hindered.

  In addition, with the increase in data communication other than voice calls such as Internet connection and mail transmission / reception as portable wireless device applications, a foldable casing composed of a display unit and an input key unit is adopted in the portable wireless device. A lot is happening. Even when such a case is placed on a desk or the like made of a material containing metal at least in part and a portable wireless device is used using a built-in antenna built in the input key, the built-in antenna Since it is close to metal, the gain of the built-in antenna is reduced, which hinders wireless transmission / reception operation by the portable wireless device.

  In order to avoid such a built-in gain reduction, a diversity-type portable wireless device is disclosed in Patent Document 1 in which a built-in type and an exposed type are provided in a casing and automatically switched to an antenna having a strong electric field strength to be received. Has been.

  Patent Document 2 discloses “antenna device and mobile communication device including this antenna device”. The paragraph 0012 and FIG. 1 disclose an antenna switching circuit for diversity reception.

  Further, Patent Document 3 discloses a “mobile radio terminal apparatus having a matching circuit”. The claim 1, paragraphs 0007 and 0025 to 0033, and FIGS. 1 and 3 disclose a metal detection means and a technique for switching a plurality of circuits in accordance with the detection result of the detection means. Further, in claim 7, paragraphs 0043 to 0049 and FIG. 3, two types of antennas having different impedances and a switch for switching these antennas are disclosed.

JP 09-135120 A JP 2001-136002 A Japanese Patent No. 3360051

  However, the diversity systems disclosed in Patent Documents 1 and 2 have a problem that even if the electric field strength increases due to, for example, noise or a reflected input of radio waves radiated by itself, the antenna is switched to the antenna. .

  Moreover, in the technique disclosed in Patent Document 3, the only metal detection means disclosed is based on the magnetic force between the metal and the detection means, so the distance from the metal is a predetermined distance or more. It is difficult to detect the magnitude of the distance. For this reason, the technique disclosed in Patent Document 3 has a problem in that it cannot accurately detect the state of radio wave interference caused by metal.

  Therefore, an object of the present invention is to provide a portable wireless device and a wireless communication method that can select an antenna having a better gain and have excellent transmission / reception characteristics.

  According to the present invention, in a portable radio apparatus having a radio transmission / reception circuit and first and second antennas, detection signals corresponding to the distances of the first and second antennas to radio wave obstacles are respectively output. An antenna having a long distance to a radio wave obstacle among the first and second antennas based on detection signals of the first and second sensors. A portable wireless device connected to the wireless transmission / reception circuit is obtained.

  The first antenna is an exposed type that is always exposed from the casing or can be stored / exposed to the casing, and the second antenna is a built-in type that is built in the casing. May be.

  Each of the first and second sensors includes a signal wave generating unit that generates a signal wave that can be reflected by a radio wave obstacle, and a signal wave receiving unit that receives the signal wave reflected by the electric field obstacle. And detecting distances to the radio wave obstacles of the first and second antennas based on the time required from when the signal wave generator is generated until the signal wave is received by the signal wave receiver. You may do.

  In addition, when provided with a field strength detection circuit for detecting the received field strength by each of the first and second antennas, and the difference between detection signals of the first and second sensors is within a predetermined range, Based on a detection signal of the electric field strength detection circuit, an antenna having a strong electric field strength among the first and second antennas may be connected to the wireless transmission / reception circuit.

  Furthermore, the mobile wireless device may be a mobile phone, an information processing terminal with a wireless communication function, or a wireless communication device.

  According to the present invention, in the wireless communication method using the portable wireless device having the first and second antennas, the step of detecting the distance to the radio wave obstacles of the first and second antennas; And performing a wireless communication using an antenna having a long distance to the radio wave obstruction among the first and second antennas.

  The first antenna is an exposed type that is always exposed from the casing of the portable wireless device or can be stored / exposed to the casing, and the second antenna is built in the casing. It may be a built-in type.

  Further, the distance detecting step, for each of the first and second antennas, generating a signal wave that can be reflected by a radio wave obstacle, receiving a signal wave reflected by an electric field obstacle, Detecting a distance from the first or the second antenna to a radio wave obstruction based on a required time from generation of the signal wave generation unit to reception of the signal wave by the signal wave reception unit; May be included.

  Further, when the difference between the detection electric field intensity of each of the first and second antennas and the detection signal of the first and second sensors is within a predetermined range, the first and second antennas are detected. There may be further included a step of performing wireless communication using an antenna having a strong electric field strength among the second antennas.

  The portable radio apparatus according to the present invention can select an antenna having a better gain, and has excellent transmission / reception characteristics.

  The wireless communication method according to the present invention can select an antenna with a better gain, and can perform wireless communication with excellent transmission and reception quality.

  The present invention will be described below.

  The portable radio apparatus according to the present invention outputs a detection signal corresponding to the distance between the first and second antennas to the radio wave obstacle in the portable radio apparatus having a radio transmission / reception circuit and first and second antennas. An antenna having a long distance to a radio wave obstruction among the first and second antennas based on detection signals of the first and second sensors. Connecting.

  According to another aspect of the present invention, there is provided a radio communication method using a portable radio apparatus having a first antenna and a second antenna, and a step of detecting a distance between the first and second antennas to a radio wave obstacle. And a step of performing wireless communication using an antenna having a long distance to the radio wave obstacle among the first and second antennas.

  Hereinafter, the present invention will be described more specifically and in detail by describing embodiments of the present invention with reference to the drawings.

  Referring to FIG. 1, a mobile phone as a mobile radio apparatus according to Embodiment 1 of the present invention has a radio transmission / reception circuit 6 and first and second antennas 1 and 2 connectable to the radio transmission / reception circuit 6. is doing. The first antenna 1 is an exposed type that is always exposed from a casing of the mobile phone (not shown) or can be stored / exposed to the casing, and is, for example, a pop-up rod / spiral antenna. The second antenna 2 is a built-in type built in the housing, and is, for example, a loop antenna.

  The cellular phone further includes a switch 5 capable of selectively connecting the radio transmission / reception circuit 6 and the first and second antennas 1 and 2, a metal material for the first and second antennas 1 and 2, and the like. First and second sensors 3 and 4 for detecting the distance to the radio wave obstacle, respectively, and first and second antennas 1 and 2 based on detection signals of the first and second sensors 3 and 4. And a control unit 7 that controls selection by the switch 5 so that an antenna having a long distance to the metal material is connected to the wireless transmission / reception circuit 6.

  The first and second antennas 1 and 2 radiate electromagnetic waves in the space and receive electromagnetic waves in the space, and the signal is passed to the wireless transmission / reception circuit 6 via the switch 5.

  The first and second sensors 3 and 4 are arranged in close proximity to the first and second antennas 1 and 2, respectively, detect a metal material adjacent to the first and second antennas 1 and 2, and are proportional to the distance between the sensors and the objects. The numerical value is transmitted to the control unit 7.

  The switch 5 selects a signal to enter the wireless transmission / reception circuit 6 from the first and second antennas 1 and 2 according to the control unit 7.

  The wireless transmission / reception circuit 6 modulates and transmits information to be transmitted while demodulating the received information.

  The control unit 7 controls the switch 5 in an appropriate direction based on information from the first and second sensors 3 and 4.

  In the present invention, the radio wave obstruction may be, for example, a dielectric or an organic substance other than metal as long as it affects the antenna gain.

  The first and second sensors 3 and 4 have the following configuration, for example.

  Referring to FIG. 3, the first sensor 3 (the same applies to the second sensor 4) includes a signal wave generator 31, a signal wave receiver 32, and a controller 33.

  The signal wave generating unit 31 generates a signal wave having a property of being reflected by the radio wave obstacle 8 such as high frequency, infrared rays, or ultraviolet rays. The signal wave generated and emitted by the signal wave generator 31 is reflected when it reaches the radio wave obstacle 8. The reflected wave is received by the signal wave receiving unit 32.

  Based on the oscillation time of the signal wave by the signal wave generation unit 31 and the reception time of the signal wave by the signal wave reception unit 32, the controller 33 oscillates the signal wave from the signal wave generation unit 31 and then the signal wave reception unit 32. The time required until the signal is received is calculated, and the distance to the radio wave obstacle 8 is specified based on the required time.

  Since the first and second sensors 3 and 4 have such a configuration, the distance to the radio wave obstacle can be accurately detected.

  The controller 33 may not be provided separately for the first and second sensors 3 and 4 but may be provided in common for these sensors.

  Next, the operation of the portable wireless device according to the present embodiment will be described as a wireless communication method according to the present invention.

  Referring to FIG. 1, during normal transmission / reception, switch 5 is connected to first antenna 1, and communication between the base station and radio transmission / reception circuit 6 is performed via these.

  When the metal material 8 approaches the first sensor 3 in this state, the detection circuit inside the first sensor 3 works, and the result is transmitted to the control unit 7 as a detection signal.

  This detection signal is digitized, and the value is determined by the distance between the first sensor 3 and the metal material 8. The relationship between the second antenna 2 and the second sensor 4 is also equivalent to the above.

  The control unit 7 constantly monitors the operation of the sensor 3 and the sensor 4, compares the detection signals output from them, and connects the radio transmission / reception circuit 6 to the antenna farther away from the metal material. The switch 5 is controlled as described above.

  With the above operation, it is possible to always select an antenna that is relatively far from a radio wave obstacle such as a metal material, that is, is less susceptible to communication interference, and can realize stable transmission / reception characteristics.

  Referring to FIG. 2, the mobile phone according to the second embodiment of the present invention is different from the first embodiment shown in FIG. 1 in that the control unit 7 ′ includes an electric field strength detection circuit 71 described later. . Since the other structure is the same as that of Example 1, description is abbreviate | omitted.

  The electric field strength detection circuit 71 detects the received electric field strength by the first and second antennas 1 and 2, respectively.

  When the difference between the detection signals of the first and second sensors 3 and 4 is within a predetermined range, that is, the control unit 7 ′, that is, with respect to the respective radio wave obstacles 8 of the first and second antennas 1 and 2. When the distance difference is not so large as to cause a problem, an antenna having a strong electric field strength among the first and second antennas 1 and 2 is connected to the radio transmission / reception circuit 6 based on the detection signal of the electric field strength detection circuit 71. Diversity reception for controlling selection by the switch 5 is performed so as to be connected.

  The electric field strength detection circuit 71 may be provided not in the control unit but in a wireless transmission / reception circuit.

  Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications can be made within the technical scope described in the claims. Needless to say.

  For example, the portable wireless device according to the present invention is not limited to a cellular phone, but is an information processing terminal with a wireless communication function such as a PDA (Personal Digital Assistant) or a wireless LAN (Local Area Network) card or a wireless video / audio communication device. It may be a communication device.

  In the embodiment, two antennas are switched. However, in the present invention, three or more antennas may be switched according to the distance to the radio wave obstacle.

It is a block diagram which shows the structure of the portable radio | wireless apparatus by Example 1 of this invention. It is a block diagram which shows the structure of the portable radio | wireless apparatus by Example 2 of this invention. It is a figure which shows the 1st sensor (2nd sensor) in the portable radio | wireless apparatus by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st antenna 2 2nd antenna 3 1st sensor 31 Signal wave generation part 32 Signal wave receiving part 33 Controller 4 2nd sensor 5 Switch 6 Wireless transmission / reception circuit 7 Control part 71 Electric field strength detection circuit 8 Radio wave interference object

Claims (9)

In a portable radio apparatus having a radio transceiver circuit and first and second antennas,
A first sensor and a second sensor for outputting detection signals corresponding to distances between the first antenna and the second antenna to a radio wave obstacle, respectively;
The first and second sensors include a signal wave generator that generates a high-frequency signal wave that can be reflected by a radio wave obstacle, and a signal wave receiver that receives a high-frequency signal wave reflected by the radio wave obstacle. Each with
Based on detection signals of the first and second sensors, an antenna having a long distance to a radio wave obstruction among the first and second antennas is connected to the radio transmission / reception circuit. Portable wireless device. The first antenna is an exposed type that is always exposed from the casing or can be stored / exposed to the casing.
The portable radio apparatus according to claim 1, wherein the second antenna is a built-in type built in the housing.   The first and second sensors are configured to detect the first and second antennas based on a required time from when the signal wave is generated to when the signal wave is received by the signal wave receiving unit. The portable wireless device according to claim 1, wherein the distance to the obstacle is detected. An electric field strength detection circuit for detecting a received electric field strength by each of the first and second antennas;
When the difference between the detection signals of the first and second sensors is within a predetermined range, the electric field strength of the first and second antennas is based on the detection signal of the electric field strength detection circuit. The portable radio apparatus according to claim 1, wherein a strong antenna is connected to the radio transmission / reception circuit.   The portable wireless device according to any one of claims 1 to 4, wherein the portable wireless device is a mobile phone, an information processing terminal with a wireless communication function, or a wireless communication device. In a wireless communication method using a portable wireless device having first and second antennas,
Detecting the distance of the first and second antennas to radio wave obstacles;
In the distance detecting step, for each of the first and second antennas, a step of generating a high-frequency signal wave that can be reflected by a radio wave obstacle, and a high-frequency signal wave reflected by the radio wave obstacle are received. Including the steps of:
And a step of performing wireless communication using an antenna having a long distance to a radio wave obstruction among the first and second antennas. The first antenna is an exposed type that is always exposed from the casing of the portable wireless device or can be stored / exposed to the casing.
The wireless communication method according to claim 6, wherein the second antenna is a built-in type built in the housing. In the distance detection step, for each of the first and second antennas, the first wave is generated based on a required time from when the signal wave generating unit is generated until the signal wave receiving unit receives the signal wave. The wireless communication method according to claim 6, further comprising a step of detecting a distance of the second antenna to a radio wave obstacle. Detecting received electric field strength by each of the first and second antennas;
Performing wireless communication using an antenna having a strong electric field strength among the first and second antennas when a difference between detection signals of the first and second sensors is within a predetermined range; the wireless communication method according to any one of claims 6 to 8 further comprising a.

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