Base station, wireless communication system, and wireless communication method

Abstract

A base station according to an embodiment performs wireless communication with a terminal within a predetermined area by using a directional antenna, and comprises: an acquisition unit that acquires data from a database storing data indicating the suitable antenna directivity for each terminal state measured or direction of arrival of radio waves from the terminal in a scale model in which a structure in a predetermined area has been reduced by a predetermined scale factor; a collection unit that collects the state of an actual terminal in the predetermined area or the direction of arrival of radio waves from the actual terminal; and a control unit that controls the directivity of the directional antenna with respect to the actual terminal within the predetermined area on the basis of the state of the terminal or the direction of arrival of radio waves from the terminal collected by the collection unit, and the data acquired by the acquisition unit.

Description

[Technical field]

[0001] The present invention relates to a base station, a wireless communication system, and a wireless communication method. [Background technology]

[0002] The recent explosive spread of wireless communication devices has led to an increased demand for wireless communication. Massive MIMO transmission, which uses a large number of antennas, is being put to practical use as one of the technologies to increase the transmission capacity of wireless communication. One method of Massive MIMO transmission is to apply analog beamforming. For example, a base station performs Massive MIMO transmission using digital signal processing after setting the antenna directionality to the terminal in advance.

[0003] In a conventional wireless communication system, a base station uses a training signal to measure the received power for each direction of the directivity of each antenna in order to set the directivity of the antenna. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Shinichi Ichibutsubo, "Establishment of scale model method for radio wave propagation", Grant-in-Aid for Scientific Research (Grant-in-Aid for Scientific Research), Research Results Report, [online], May 18, 2012, Form C-19, Internet<URL:https: / / kaken.nii.ac.jp / ja / file / KAKENHI-PROJECT-21560403 / 21560403seika.pdf> Summary of the Invention [Problem to be solved by the invention]

[0005] However, as the directional pattern of the antenna increases, the time required for measuring the received power increases. Also, when the terminal or base station moves or the orientation of the terminal changes, the measured received power information becomes outdated, and it may not be possible to set an effective antenna directivity.

[0006] The present invention has been made in consideration of the above-mentioned problems, and has an object to provide a base station, a wireless communication system, and a wireless communication method that can efficiently set antenna directivity. [Means for solving the problem]

[0007] A base station according to an embodiment of the present invention is a base station that uses a directional antenna to wirelessly communicate with a terminal within a predetermined area, and is measured using a scale model in which a structure within the predetermined area is reduced at a predetermined scale ratio. Direction of arrival of radio waves from the terminal An acquisition unit that acquires data from a database that holds data indicating an antenna directivity suitable for each area; Direction of arrival of radio waves from the terminal A collection unit that collects the Direction of arrival of radio waves from the terminal and a control unit that controls the directivity of a directional antenna for a terminal in an actual location within a specified area based on the data acquired by the acquisition unit.

[0008] In addition, in a wireless communication system according to an embodiment of the present invention, a base station performs wireless communication with a terminal using a directional antenna within a predetermined area, and a structure within the predetermined area is measured on a scale model reduced at a predetermined scale ratio. Direction of arrival of radio waves from the terminal The base station includes a database for storing data indicating an antenna directivity of a base station suitable for each area, and the base station includes a Direction of arrival of radio waves from the terminal A collection unit that collects the Direction of arrival of radio waves from the terminal and a control unit that controls the directivity of a directional antenna for a terminal in an actual location within a specified area based on the data held in the database.

[0009] In addition, a wireless communication method according to an embodiment of the present invention is a wireless communication method in which a base station wirelessly communicates with a terminal using a directional antenna within a predetermined area, and a structure within the predetermined area is measured on a scale model reduced at a predetermined scale ratio. Direction of arrival of radio waves from the terminal An acquisition step of acquiring data from a database that holds data indicating an antenna directivity of a base station suitable for each area; Direction of arrival of radio waves from the terminal A collecting step of collecting the collected Direction of arrival of radio waves from the terminal and a control step of controlling the directivity of a directional antenna for a terminal in an actual location within a predetermined area based on the acquired data. Effect of the Invention

[0010] According to the present invention, the directivity of an antenna can be set efficiently. [Brief description of the drawings]

[0011] [Figure 1] 1 is a diagram illustrating an example of an outline of the configuration of a wireless communication system according to an embodiment; [Diagram 2] FIG. 2 is a functional block diagram illustrating functions of a base station according to an embodiment. [Diagram 3] 11 is a flowchart illustrating a process for storing data in a database as an initial setting. [Figure 4] 13 is a flowchart showing an example of the operation of the terminal. [Diagram 5] 13 is a flowchart showing an example of the operation of a base station. [Figure 6] FIG. 1 is a diagram illustrating a wireless communication system of a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] First, the background that led to the invention will be described with reference to Fig. 6. Fig. 6 is a diagram that illustrates a wireless communication system of a comparative example.

[0013] In the wireless communication system of the comparative example, a base station measures the received power for each direction of the directivity of each antenna by using a training signal in order to set the directivity of the antenna.

[0014] However, as the antenna directivity pattern increases, the time required to measure the received power increases, and when the terminal or base station moves or the terminal changes orientation, the measured received power information becomes outdated, making it impossible to set an effective antenna directivity.

[0015] Therefore, a wireless communication system according to an embodiment is configured to be able to efficiently set the directivity of an antenna.

[0016] A wireless communication system according to an embodiment will be described below with reference to the drawings. Fig. 1 is a diagram illustrating an example of an outline of the configuration of a wireless communication system 1 according to an embodiment.

[0017] 1, the wireless communication system 1 includes, for example, a base station 2, a plurality of terminals 3, and a reflector 4 (or a relay station). The base station 2 transmits radio waves to each of the terminals 3 via the reflector 4, and performs wireless communication with each of the terminals 3.

[0018] 2 is a functional block diagram illustrating functions of a base station 2 according to an embodiment. As shown in Fig. 2, the base station 2 includes, for example, a database 20, an acquisition unit 21, a collection unit 22, an imaging unit (camera) 23, a control unit 24, and a directional antenna 25, and performs wireless communication with a terminal 3 using the directional antenna 25 within a predetermined area.

[0019] The database 20 is a database that holds data indicating the state of a terminal measured in a scale model in which a structure in a predetermined area is reduced at a predetermined scale rate or the antenna directivity suitable for each direction of arrival of radio waves from the terminal. Note that the database 20 does not need to be provided in the base station 2, and may be provided in another device.

[0020] The acquisition unit 21 acquires data held in the database 20 and outputs the data to the control unit 24 .

[0021] The collecting unit 22 collects the state of the terminal 3 at the actual site within a predetermined area or the direction of arrival of the radio wave from the terminal 3, and outputs the collected information to the control unit .

[0022] The imaging unit 23 is an imaging device such as a camera, which captures an image and outputs it to the collection unit 22 .

[0023] The collecting unit 22 may collect the arrival direction of the radio wave from the terminal 3 based on the shielding environment for the terminal 3 included in the image captured by the imaging unit 23. The collecting unit 22 may also collect the arrival direction of the radio wave arriving via the reflector 4 shown in FIG. 1 (or a relay station not shown).

[0024] The control unit 24 controls each unit constituting the base station 2. For example, the control unit 24 controls the directivity of the directional antenna 25 with respect to the terminal 3 at the actual site within a predetermined area, based on the state of the terminal 3 collected by the collection unit 22 or the direction of arrival of the radio waves from the terminal 3, and the data acquired by the acquisition unit 21.

[0025] Next, a description will be given of an example of the operation of the wireless communication system 1. First, as an initial setting, data indicating the state of a terminal measured in a scale model in which a structure in a predetermined area is reduced at a predetermined scale rate or the antenna directivity suitable for each direction of arrival of radio waves from the terminal is stored in the database 20.

[0026] FIG. 3 is a flowchart illustrating a process for storing data in the database 20 as an initial setting.

[0027] As shown in FIG. 3, first, using the base station and terminal installed in the scale model described above, the state of the terminal is set with respect to the directional antenna (S100), and the beam radiated by the directional antenna is switched (S102).

[0028] Next, the base station measures, for example, the received power from the terminal, and collects the state of the terminal within a predetermined area of ​​the scale model or the direction of arrival of the radio waves from the terminal (S104).

[0029] Then, data indicating antenna directivity suitable for each state of the terminal measured in the scale model or the direction of arrival of radio waves from the terminal is stored in the database 20, and the data is updated (S106).

[0030] Next, a description will be given of an example of the operation of the terminal 3. Fig. 4 is a flowchart showing an example of the operation of the terminal 3. As shown in Fig. 4, the terminal 3 measures the state (position, orientation, etc.) of the terminal (S200), and notifies the base station of the measurement result (S202).

[0031] Fig. 5 is a flowchart showing an example of the operation of the base station 2. As shown in Fig. 5, in the base station 2, the collection unit 22 collects the state of the terminal 3 in the field (S300).

[0032] Next, the control unit 24 selects the optimal directivity of the directional antenna 25 from the database 20 (S302), and controls (sets) the directivity of the directional antenna 25 (S304).

[0033] Then, the base station 2 transmits a signal to the terminal 3 using the set directivity of the directional antenna 25 (S306).

[0034] In this way, the wireless communication system 1 controls the directivity of the directional antenna 25 using data acquired using the scale model, and therefore the directivity of the directional antenna 25 can be set efficiently.

[0035] Each component of the wireless communication system 1 may be configured, in part or in whole, by hardware such as a PLD (Programmable Logic Device) or an FPGA (Field Programmable Gate Array), or may be configured as a program executed by a processor such as a CPU.

[0036] For example, each unit constituting the wireless communication system 1 can be realized using a computer and a program, and the program can be recorded on a storage medium or provided via a network. [Explanation of symbols]

[0037] REFERENCE SIGNS LIST 1 wireless communication system, 2 base station, 3 terminal, 4 reflector, 20 database, 21 acquisition unit, 22 collection unit, 23 imaging unit, 24 control unit, 25 directional antenna

Claims

1. In a base station that uses a directional antenna within a specified area to wirelessly communicate with a terminal, an acquisition unit that acquires data from a database that holds data indicating antenna directivities suitable for each direction of arrival of radio waves from a terminal, the data being measured in a scale model in which a structure in a predetermined area is reduced at a predetermined scale rate; A collection unit that collects directions of arrival of radio waves from terminals in a predetermined area; a control unit that controls a directivity of a directional antenna for a terminal in an actual location within a predetermined area based on the arrival direction of radio waves from the terminal collected by the collection unit and the data acquired by the acquisition unit; A base station comprising:

2. The imaging device further includes an imaging device for capturing an image. The collecting unit includes: Collecting the direction of arrival of radio waves from a terminal based on a shielding environment for the terminal included in an image captured by the imaging device. The base station according to claim 1 ,

3. In a wireless communication system in which a base station uses a directional antenna to wirelessly communicate with a terminal within a specific area, a database that holds data indicating antenna directivity of a base station suitable for each direction of arrival of radio waves from a terminal measured in a scale model obtained by reducing structures in a predetermined area at a predetermined scale ratio; The base station, A collection unit that collects directions of arrival of radio waves from terminals in a predetermined area; a control unit that controls the directivity of a directional antenna for a terminal in a specific area based on the direction of arrival of radio waves from the terminal collected by the collection unit and the data held in the database; A wireless communication system comprising:

4. The base station, The imaging device further includes an imaging device for capturing an image. The collecting unit includes: Collecting the direction of arrival of radio waves from a terminal based on a shielding environment for the terminal included in an image captured by the imaging device.

4. The wireless communication system according to claim 3,

5. A relay station that relays radio waves, or a reflector that reflects radio waves and The collecting unit includes: Collecting the direction of arrival of radio waves arriving via the relay station or the reflector.

5. The wireless communication system according to claim 3 or 4,

6. A wireless communication method in which a base station uses a directional antenna to wirelessly communicate with a terminal within a predetermined area, an acquisition step of acquiring data from a database that holds data indicating antenna directivities of base stations suitable for each direction of arrival of radio waves from terminals, the data being measured in a scale model in which structures within a predetermined area are reduced at a predetermined scale rate; A collection step of collecting directions of arrival of radio waves from terminals in a predetermined area; A control step of controlling the directivity of a directional antenna for a terminal in a specific area based on the collected direction of arrival of radio waves from the terminal and the acquired data; 13. A wireless communication method comprising:

7. The method further includes the step of capturing an image from a base station; In the collecting step, Collecting the direction of arrival of radio waves from the terminal based on the obstruction environment for the terminal included in the image captured in the imaging step.

7. The wireless communication method according to claim 6,

8. In the collecting step, Collecting information on the direction of arrival of radio waves via relay stations that relay radio waves or reflectors that reflect radio waves 8. The wireless communication method according to claim 6 or 7, characterized in that:

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