JP2013051570A - Wireless communication device - Google Patents

Abstract

A wireless communication apparatus capable of suppressing unexpected leakage and interference of transmitted radio waves is provided.
In a wireless communication apparatus that performs wireless communication with at least one wireless communication terminal via an antenna, an image acquisition unit that acquires an image of a space that is a target of wireless communication, and an image acquisition unit that acquires the image. The user position specifying unit 21 that specifies the position of the user of the wireless communication terminal based on the obtained image, and the direction of the antenna 17 so that the radiation area of the antenna 17 includes the position specified by the user position specifying unit 21. And an antenna control unit 16 for changing the characteristics.
[Selection] Figure 4

Description

  The present invention relates to a wireless communication apparatus that performs wireless communication with at least one wireless communication terminal via an antenna.

  Radio waves of the wireless communication device have different radiation ranges depending on the characteristics of the antenna. For radio waves with high straightness, use a highly directional antenna to adjust the radiation direction of the antenna in the direction in which the communication partner's device is installed, or use a non-directional antenna to A device that can be installed at an arbitrary location so that the device of FIG.

  For example, a technology that controls the radiation direction of radio waves using a beam forming technique that controls the radiation direction of radio waves by using a plurality of omnidirectional antennas and digital signal processing is known for millimeter waves. (For example, see Non-Patent Documents 1 and 2).

  As a wireless communication apparatus that performs wireless communication with at least one wireless communication terminal via an antenna, other information wireless communication terminals can be used depending on the reception intensity of radio waves measured by an information wireless communication terminal equipped with a directional antenna having a rotation function. Is known (for example, see Patent Document 1).

  Moreover, in the above-mentioned Patent Document 1, a directional antenna having a rotation function is mounted for the purpose of detecting an information wireless communication terminal that cannot be detected only by one information wireless communication terminal having a directional antenna having a rotation function. There is also disclosed a technique for mutually detecting the positions of information wireless communication terminals based on radio wave reception intensities measured by a plurality of information wireless communication terminals.

  However, although the above-described conventional techniques can grasp the position of the wireless communication terminal of the communication partner, they are not considered for unexpected leakage or interference of radio waves transmitted and received in the subsequent wireless communication. There was a problem.

  The present invention has been made to solve such a conventional problem, and an object of the present invention is to provide a wireless communication apparatus capable of suppressing unexpected leakage and interference of transmission radio waves.

  In order to solve the above-described problem, the wireless communication device of the present invention is an image acquisition device that acquires an image of a space targeted for wireless communication in a wireless communication device that performs wireless communication with at least one wireless communication terminal via an antenna. A user position specifying unit that specifies the position of the user of the wireless communication terminal, and a radiation area of the antenna is specified by the user position specifying unit based on the image acquired by the image acquisition unit. An antenna control unit that changes the directivity of the antenna so as to include the position.

  The present invention can provide a wireless communication apparatus that can suppress unexpected leakage and interference of transmission radio waves.

It is a block diagram which shows the radio | wireless network which used as a master the video conference apparatus which comprises a radio | wireless communication apparatus. It is a conceptual diagram which shows an example of the radiation | emission image of the electromagnetic wave by the video conference apparatus shown in FIG. It is a conceptual diagram which shows the radiation characteristic of the electromagnetic wave of a dipole antenna and a directional antenna. It is a block diagram of the radio | wireless communication apparatus which concerns on the 1st Embodiment of this invention. It is a conceptual diagram which shows the radiation area of the electromagnetic wave by the radio | wireless communication apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart for demonstrating the antenna control operation | movement of the radio | wireless communication apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart for demonstrating the user position specific process of the radio | wireless communication apparatus which concerns on the 1st Embodiment of this invention. It is a block diagram of the radio | wireless communication apparatus which concerns on the 2nd Embodiment of this invention. It is a block diagram of the radio | wireless communication apparatus which concerns on the 3rd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the wireless communication device according to the embodiment of the present invention is configured by, for example, a video conference device 1, and a wireless network 2 having the video conference device 1 as a master is configured with a wireless communication terminal 3. . In FIG. 4, three wireless communication devices 3 are illustrated, but the number is not limited.

  Conventionally, a radio communication device used when configuring such a radio network 2 is often provided with a dipole antenna having almost no directivity, and radio waves are spread and propagated over a wide range.

  Due to the characteristics of radio waves, radio waves having a channel frequency of 2.4 GHz or 5 GHz, which have been used in conventional wireless LAN (Local Area Network) or the like, spread to some extent. For example, the radio wave radiation image 5 when the video conference device 1 constituting the wireless communication device used in the wireless network 2 shown in FIG. 1 is arranged in a limited space such as a conference room is as follows: As shown in FIG.

  Thus, when the video conference device 1 serving as the master configures the radio network 2 with the radio communication terminal 3, the radio waves radiated from the video conference device 1 are in a direction in which no user of the radio communication terminal 3 exists. Will also be emitted.

  Of course, there is no problem if the user's wireless communication terminal 3 exists ahead of the emitted radio wave, but from the viewpoint of security, access to the wireless network 2 by a wireless communication terminal other than the user participating in the conference. Is not desirable.

  An antenna element used in a wireless communication device has various characteristics depending on a shape, a material, and the like. For example, as indicated by reference numeral 7 in FIG. 3, the dipole antenna generally does not have high directivity and propagates radio waves over a relatively wide range.

  Therefore, this type of antenna has an advantage that it can be used without fine adjustment of the installation direction and the like when installing a wireless communication device, and is widely used in current wireless communication devices.

  In addition, since millimeter waves in the 60 GHz band and the like have strong directivity, directivity can be controlled by a plurality of omnidirectional antenna devices and signal processing such as phase processing of a transmission waveform. For wireless communication using a wave band, a system using an omnidirectional antenna has been studied.

  On the other hand, as indicated by reference numeral 8 in FIG. 3, the directional antenna is often used for relaying between radio stations, communication between outdoor access points, and the like because the area through which radio waves propagate is small. However, if the characteristic that the area where radio waves propagate is limited is used, the directional antenna can reduce the radiation area of unnecessary radio waves. Thus, it is possible to configure a wireless network in consideration of security.

  In the above description, the example in which the wireless communication device according to the present invention is configured by the video conference device 1 has been described. However, the wireless communication device according to the present invention can be a projector, a host wireless communication terminal, a portable terminal, or an access. You may comprise by a point etc.

  The radio communication apparatus according to the embodiment of the present invention as described above will be described in detail below.

(First embodiment)
As illustrated in FIG. 4, the wireless communication device 10 according to the first embodiment of the present invention includes an imaging device 11, an image processing module 12, a system control device 13, a storage device 14, and a wireless communication unit 15. An antenna control unit 16, an antenna 17, and an input device 18 including a keyboard device, a pointing device, and the like.

  The imaging device 11 includes a plurality of lenses 11a to 11c and an image sensor 11d such as a complementary metal oxide semiconductor (CMOS) image sensor or a charge coupled device (CCD) image sensor. The photographing apparatus 11 acquires an image of a space such as a conference room that is a target of wireless communication.

  The image processing module 12 is, for example, a DSP (Digital Signal Processing), FGPA (Field-programmable Gate Array), LSI (Large Scale Integration), or the like that performs binarization processing, filter processing, and the like on an image captured by the imaging device 11. It is constituted by.

  The imaging device 11 and the image processing module 12 constitute an image acquisition unit 20. If the installation location is known relative to the wireless communication device 10, an external photographing device such as a video camera may be used instead of the photographing device 11. In this case, an interface circuit with an external photographing device is provided in place of the photographing device 11 and the image processing module 12, and this interface circuit constitutes the image acquisition unit 20.

  The system control device 13 includes a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and the like. The ROM and the storage device 14 store a program for causing the device to function as the wireless communication device 10.

  That is, when the CPU executes a program stored in the ROM and the storage device 14 using the RAM as a work area, the device functions as the wireless communication device 10. In the present embodiment, the system control device 13 constitutes a user position specifying unit 21.

  The user position specifying unit 21 identifies a face image from the images obtained from the image acquisition unit 20, authenticates the user based on the identified face image, and positions the user who is authenticated as a legitimate one Is to identify.

  For example, face information of users such as conference participants is registered in advance in the user position specifying unit 21, and the user position specifying unit 21 can select from the images acquired by the image acquisition unit 20. By comparing the identified face image with a pre-registered face image, it is determined whether or not the user corresponding to each face image is valid.

  Here, the user position specifying unit 21 specifies the relative position of the user determined to be valid with respect to the wireless communication device 10 based on the focus adjustment information obtained from the image acquisition unit 20, and the like. Position information indicating the specified position and an ID for identifying the user are associated with each other and stored in the storage device 14.

  In the present embodiment, the system control device 13 has been described as identifying the face image from the images acquired by the image acquisition unit 20 and authenticating the user based on the identified face image. In the present invention, the system control device 13 identifies and authenticates an image of a user's part that can be used for biometric authentication, such as an iris image or an ear image, instead of a face image. Also good.

  Further, in the present invention, the system control device 13 identifies a marker image representing a marker attached to an object placed near the user, such as the wireless communication terminal 3 or an ID card, and the identified marker image The user may be authenticated based on the above. Here, the marker includes a pattern such as a barcode, a character string, and the like.

  The storage device 14 is configured by a nonvolatile storage medium such as a hard disk device or a flash memory. Each wireless communication unit 15 configures a wireless network 2 with the wireless communication terminal 3 via an antenna 17 and transmits / receives a signal to / from each wireless communication terminal 3.

  For example, the wireless communication unit 15 includes a transmission circuit having an upconverter, a filter, an amplifier, and the like for transmitting a signal to be transmitted from the system control device 13 to each wireless communication terminal 3 via the antenna 17, and each wireless communication. The receiver 3 includes a down converter, a filter, an amplifier, and the like for outputting a signal transmitted from the terminal 3 to the system controller 13.

  The antenna 17 includes a plurality of directional antenna elements 17a to 17c. In FIG. 4, three directional antenna elements 17a to 17c are illustrated, but the number is not limited.

  The antenna control unit 16 selects at least one directional antenna element from the directional antenna elements 17a to 17c, and transmits and receives radio waves to and from the wireless communication terminal 3 via the selected directional antenna element. It comes to let you.

  Specifically, the antenna control unit 16 adds at least one directional antenna element from the directional antenna elements 17 a to 17 c so that the radiation area of the antenna 17 includes the position represented by the position information stored in the storage device 14. It comes to choose.

  Further, the antenna control unit 16 radiates from the directional antenna elements selected from the directional antenna elements 17a to 17c so that the radiation area of the antenna 17 includes the position represented by the position information stored in the storage device 14 to the minimum. The transmission power of the received radio waves is changed.

  For example, in the example shown in FIG. 5, the antenna control unit 16 includes a radiation area 19a of the directional antenna element 17a, a radiation area 19b of the directional antenna element 17b, and a radiation area 19c of the directional antenna element 17c. Thus, the directional antenna element 17a is selected so that the radiation area of the antenna 17 includes the position represented by the position information stored in the storage device 14, and the transmission power of the radio wave radiated from the directional antenna element 17a is minimized. It is supposed to change to.

  The antenna control operation of the wireless communication apparatus 10 configured as described above will be described with reference to FIGS. Note that the antenna control operation of the wireless communication device 10 shown below is performed when an instruction to configure the wireless network is input to the input device 18, when communication with the wireless communication terminal 3 configuring the wireless network is disconnected, or Start at regular time intervals (eg, every few minutes).

  First, an image of a space to be subjected to wireless communication is acquired by the image acquisition unit 20 (step S1: image acquisition step), and the position of the user of the wireless communication terminal 3 is determined based on the acquired image. The user position specifying process specified by the unit 21 is executed (step S2: user position specifying step).

  The position information indicating the position of the user of the wireless communication terminal 3 is stored in the storage device 14 by the user position specifying unit 21. At this time, if the position information has already been stored in the storage device 14, the position information stored in the storage device 14 and the position information stored in the storage device 14 by the user position specifying unit 21 are obtained. It is compared by the user position specifying unit 21 to determine whether or not the user has moved (step S3).

  Here, when it is determined that the user has not moved, the storage of the position information in the storage device 14 by the user position specifying unit 21 is canceled, and the antenna control operation ends. When the antenna control operation is started in response to the input of the instruction from the input device 18, the antenna control operation does not execute step S3 and executes the subsequent processing on the assumption that the user has moved. You may make it do.

  On the other hand, if it is determined in step S3 that the user has moved, the antenna control unit 16 changes the directivity of the antenna 17 so that the radiation area of the antenna 17 includes the position specified in step S2. (Step S4: antenna control step), the transmission power of the radio wave radiated from the antenna 17 is changed by the antenna control unit 16 (step S5).

  In the present embodiment, in step S3, at least one directional antenna from the directional antenna elements 17a to 17c is included so that the radiation area of the antenna 17 includes the position represented by the position information stored in the storage device 14. An element is selected by the antenna control unit 16.

  Details of the user position specifying process executed in step S2 in the antenna control operation of the wireless communication apparatus 10 will be described with reference to FIG.

  First, when a face image is detected by the user position specifying unit 21 from the images acquired by the image acquisition unit 20 (step S11), the detected face image and a pre-registered face image are detected by the user. A face authentication process is performed in which the position identification unit 21 collates and determines whether or not the user corresponding to the face image is valid (step S12).

  Here, when it is determined that the user corresponding to the face image is valid (step S13), the relative position of the user determined to be valid with respect to the wireless communication device 10 is determined. Based on the focus adjustment information obtained from the image acquisition unit 20 and the like, the user position specifying unit 21 specifies (step S14). The position information indicating the position thus specified is stored in a temporary memory such as a RAM in order to be stored in the storage device 14 as described above.

  Here, whether or not the user position specifying process end condition is satisfied is determined by the user position specifying unit 21 (step S15), and if it is determined that the user position specifying process end condition is satisfied, The person location specifying process ends. On the other hand, when it is determined that the end condition of the user position specifying process is not satisfied, the user position specifying process executes step S11 again.

  Here, as an end condition of the user position specifying process, when it is determined that all users corresponding to the face image registered in advance are valid, or acquired by the image acquisition unit 20 In some cases, face image detection processing is performed over the entire range of the image.

  As described above, the radio communication apparatus 10 according to the present embodiment adjusts the radiation area of the antenna 17 so as to include the position of the user, thereby suppressing unexpected leakage and interference of the transmission radio wave. Can do. Thereby, the wireless communication apparatus 10 according to the present embodiment can perform secure wireless communication.

  In addition, the wireless communication device 10 according to the present embodiment adjusts the transmission power of the radio wave radiated from the antenna 17 so that the radiation area of the antenna 17 includes the position of the user to the minimum, so that power saving is achieved. A stable wireless connection service can be provided.

  Further, when the wireless communication device 10 according to the present embodiment constructs a wireless communication environment such as one-to-one or one-to-many in a limited space, the position of the user of the wireless communication terminal It is not necessary to scan and grasp the location of wireless communication terminals using radio waves, or to re-scan the user's position every time the communication direction changes due to a change or movement of the user's terminal device, and recognition by image By using the technology, it is possible to quickly construct the wireless network by capturing the user's arrangement.

  Further, the wireless communication device 10 according to the present embodiment recognizes the wireless communication terminal 3 and the user of the connection destination by applying the image recognition technology when constructing a wireless network. It is possible to clarify the user who intends to use.

  In the present embodiment, the wireless communication apparatus 10 has been described as including one image acquisition unit 20, but in the present invention, a plurality of image acquisition units 20 may be included. By comprising in this way, the precision of the user's position specified by the user position specific | specification part 21 can be improved.

(Second Embodiment)
As shown in FIG. 8, the wireless communication device 30 according to the second embodiment of the present invention is different from the wireless communication device 10 according to the first embodiment of the present invention in that 1 is used instead of the antenna 17. An antenna 37 composed of two directional antenna elements is provided, and an antenna control unit 36 is provided instead of the antenna control unit 16.

  The wireless communication apparatus 30 is further provided with a motor 39 that rotationally drives the directional antenna element of the antenna 37. The antenna control unit 36 controls the motor 39 so as to change the rotational position of the directional antenna element so that the radiation area of the antenna 37 includes the position represented by the position information stored in the storage device 14. Yes.

  Similarly to the antenna control unit 16, the antenna control unit 36 is radiated from the directional antenna element so that the radiation area of the antenna 37 includes the position represented by the position information stored in the storage device 14 to the minimum. The transmission power of radio waves is changed.

  The antenna control operation of the wireless communication device 30 configured as described above will be described with reference to FIG. 6 showing the antenna control operation of the wireless communication device 10. In step S4, the antenna control operation of the wireless communication apparatus 10 is performed by controlling at least one directional antenna element from the directional antenna elements 17a to 17c so that the radiation area of the antenna 17 includes the position specified in step S2. Selected by part 16.

  On the other hand, in the antenna control operation of the wireless communication device 30, the motor 39 is changed so as to change the rotational position of the directional antenna element so that the radiation area of the antenna 37 includes the position specified in step S2 in step S4. Is controlled by the antenna control unit 36.

  As described above, the wireless communication device 30 according to the present embodiment can obtain the same effects as the wireless communication device 10 according to the first embodiment of the present invention.

(Third embodiment)
As shown in FIG. 9, the wireless communication device 40 according to the third embodiment of the present invention is different from the wireless communication device 10 according to the first embodiment of the present invention in place of the antenna 17. In this embodiment, an antenna 47 constituted by dipole antennas 47 a to 47 c is provided, and an antenna control unit 46 is provided instead of the antenna control unit 16. In FIG. 9, three dipole antennas 47a to 47c are shown, but the number is not limited.

  The antenna control unit 46 also transmits the phase and transmission power of each radio wave radiated by the dipole antennas 47a to 47c so that the radiation area of the antenna 47 includes the position represented by the position information stored in the storage device 14 to the minimum. And to change. That is, the antenna control unit 46 controls the radiation area of the antenna 47 using the beam forming technique described above.

  The antenna control operation of the wireless communication device 40 configured as described above will be described with reference to FIG. 6 showing the antenna control operation of the wireless communication device 10. In step S4, the antenna control operation of the wireless communication apparatus 10 is performed by controlling at least one directional antenna element from the directional antenna elements 17a to 17c so that the radiation area of the antenna 17 includes the position specified in step S2. The transmission power of the radio wave radiated from the antenna 17 is changed by the antenna control unit 16 in step S5.

  On the other hand, the antenna control operation of the wireless communication device 40 is performed in steps S4 and S5 so that the radiation area of the antenna 37 includes the position specified in step S2 to the minimum. The phase and transmission power of each radio wave radiated by the antenna control unit 46 are changed.

  As described above, the wireless communication device 40 according to the present embodiment can obtain the same effects as the wireless communication device 10 according to the first embodiment of the present invention.

DESCRIPTION OF SYMBOLS 1 Video conference apparatus 2 Wireless network 3 Wireless communication terminal 10, 30, 40 Wireless communication apparatus 11 Image pick-up apparatus 11a-11c Lens 11d Image sensor 12 Image processing module 13 System control apparatus 14 Storage apparatus 15 Wireless communication part 16, 36, 46 Antenna Control unit 17, 37, 47 Antenna 17a to 17c Directional antenna element 18 Input device 20 Image acquisition unit 21 User position specifying unit 39 Motor 47a to 47c Dipole antenna

JP 2003-078945 A

IEEE802.11n IEEE802.11ad

Claims (9)

In a wireless communication device that performs wireless communication with at least one wireless communication terminal via an antenna,
An image acquisition unit for acquiring an image of a space to be subjected to the wireless communication;
A user position specifying unit for specifying the position of the user of the wireless communication terminal based on the image acquired by the image acquisition unit;
A radio communication apparatus comprising: an antenna control unit that changes a directivity of the antenna so that a radiation area of the antenna includes a position specified by the user position specifying unit. The antenna is composed of a plurality of directional antenna elements,
The radio communication apparatus according to claim 1, wherein the antenna control unit changes the directivity of the antenna by selecting a directional antenna element that radiates radio waves from the plurality of directional antenna elements. . The antenna is composed of one directional antenna element,
The wireless communication apparatus according to claim 1, wherein the antenna control unit changes the directivity of the antenna by changing directions of the plurality of directional antenna elements.   The antenna control unit changes transmission power of a radio wave radiated from the antenna so that a radiation area of the antenna includes a position specified by the user position specifying unit to a minimum. Item 4. The wireless communication device according to Item 2 or Item 3. The antenna is constituted by at least three omnidirectional antenna elements,
2. The radio according to claim 1, wherein the antenna control unit changes the directivity of the antenna by changing a phase and a transmission power of a radio wave radiated from each omnidirectional antenna element. Communication device.   The user position specifying unit identifies an image of a part of a human body that can be used for biometric authentication from the image, authenticates the user based on the identified image, and is authenticated as a legitimate one 6. The wireless communication apparatus according to claim 1, wherein the position of the user is specified.   The said user position specific | specification part identifies a marker image from the said image, and pinpoints the said user's position based on the identified image, The Claim 1 thru | or 6 characterized by the above-mentioned. Wireless communication device. In a wireless communication method using a wireless communication device that performs wireless communication with at least one wireless communication terminal via an antenna,
An image acquisition step of acquiring an image of a space to be subjected to the wireless communication;
A user position specifying step for specifying the position of the user of the wireless communication terminal based on the image acquired in the image acquiring step;
An antenna control step of changing the directivity of the antenna so that the radiation area of the antenna includes the position specified in the user position specifying step. In a wireless communication program to be executed by a computer constituting a wireless communication device that performs wireless communication with at least one wireless communication terminal via an antenna,
An image acquisition step of acquiring an image of a space to be subjected to the wireless communication;
A user position specifying step for specifying the position of the user of the wireless communication terminal based on the image acquired in the image acquiring step;
An antenna control step for changing the directivity of the antenna so that the radiation area of the antenna includes the position specified in the user position specifying step.

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