Communication system and radio wave focusing plate

Abstract

This communication system includes a base station that is installed outdoors and configured to transmit and receive radio waves, a radio-wave-focusing plate that is configured to receive a radio wave transmitted from the base station and emit a radio wave using the boundary between the outdoors and indoors as a focal point, and a terminal device that is configured to receive the radio wave emitted from the radio-wave-focusing plate and communicate with the base station.

Description

[Technical Field]

[0001] The present disclosure relates to a communication system and a communication method. [Background technology]

[0002] When performing high-speed communications in a collective housing complex such as an apartment building, wired connections such as optical fiber lines or FWA (Fixed Wireless Access) using public LTE are used (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-17643 Summary of the Invention

[0004] The communication system of the present disclosure includes a base station installed outdoors and configured to transmit and receive radio waves, a radio wave focusing plate configured to receive the radio waves transmitted from the base station and emit the radio waves with the boundary between the outdoors and the indoors as a focus, and a terminal device configured to receive the radio waves emitted from the radio wave focusing plate and communicate with the base station.

[0005] The communication method disclosed herein includes the steps of transmitting and receiving radio waves, receiving the transmitted radio waves with a radio wave focusing plate and emitting the radio waves with a focus at the boundary between indoors and outdoors, and receiving the radio waves emitted from the radio wave focusing plate and communicating with a base station. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a diagram illustrating an example of the configuration of a communication system according to the first embodiment. [Figure 2] FIG. 2 is a diagram showing an example of the configuration of the radio wave focusing plate according to the first embodiment. [Figure 3]FIG. 3 is a diagram for explaining the focal position of the radio wave focusing plate according to the second embodiment. [Figure 4] FIG. 4 is a diagram for explaining the installation position of a terminal device according to the third embodiment. [Figure 5] FIG. 5 is a diagram for explaining a method for installing a radio wave converging plate according to the fourth embodiment. [Figure 6] FIG. 6 is a diagram for explaining the installation angle of the radio wave focusing plate according to the fifth embodiment. [Figure 7] FIG. 7 is a diagram for explaining a method for installing a plurality of radio wave focusing plates according to a first example of the sixth embodiment. [Figure 8] FIG. 8 is a diagram for explaining a method for installing a plurality of radio wave focusing plates according to a second example of the sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to this embodiment, and in the following embodiments, the same components are designated by the same reference numerals, and redundant explanations will be omitted.

[0008] [First embodiment] An example of the configuration of a communication system according to the first embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram showing an example of the configuration of a communication system according to the first embodiment.

[0009] 1, the communication system 1 includes a base station 10, a radio wave converging plate 12, and a terminal device 14. The communication system 1 may be, for example, a communication system compatible with millimeter wave communication capable of performing large-capacity data communication at high speed, such as a fifth-generation mobile communication system (hereinafter also referred to as "5G") or a sixth-generation mobile communication system (hereinafter also referred to as "6G").

[0010] The communication system 1 is configured to enable appropriate communication between the base station 10 and the terminal device 14 in each room of an apartment building or other collective housing, for example. Specifically, the communication system 1 is configured to enable effective transmission of radio waves from the base station 10 into the room 2 when the window glass in the room 2 of the collective housing is heat-reflecting glass or heat-absorbing glass, which makes it difficult for radio waves to pass through.

[0011] The base station 10 is installed outdoors. The base station 10 is configured to perform wireless communication with the terminal device 14. The base station 10 is configured to perform wireless communication with the terminal device 14, for example, by transmitting and receiving radio waves (millimeter waves) compatible with 5G or 6G. In this embodiment, the base station 10 is configured to perform wireless communication with the terminal device 14 via a radio wave focusing plate 12. In the example shown in FIG. 1 , the base station 10 is configured to transmit radio waves W1 toward the radio wave focusing plate 12.

[0012] The radio wave focusing plate 12 is installed outdoors. The radio wave focusing plate 12 is formed, for example, in a rectangular shape. The shape of the radio wave focusing plate 12 is not limited to a rectangular shape. The radio wave focusing plate 12 is installed, for example, on a handrail 3 provided on a balcony of the room 2. The radio wave focusing plate 12 is configured to receive radio waves from the base station 10 and emit radio waves W2. The radio wave focusing plate 12 is configured to focus the radio waves W2 at a predetermined position. In this embodiment, the radio wave focusing plate 12 is configured to focus the radio waves W2 at a focal point F at the boundary between the indoors and outdoors of the room 2. In other words, the radio wave focusing plate 12 is configured to have a focal point F at the boundary between the indoors and outdoors of the room 2.

[0013] An example of the configuration of a radio wave focusing plate according to the first embodiment will be described with reference to Fig. 2. Fig. 2 is a diagram showing an example of the configuration of a radio wave focusing plate according to the first embodiment. The radio wave focusing plate 12 is made of, for example, a metamaterial that changes the phase of an incident wave.

[0014] As shown in FIG. 2, the radio wave focusing plate 12 may include a substrate 20, a plurality of elements 20A, a plurality of elements 20B, a plurality of elements 20C, and a plurality of elements 20D.

[0015] Substrate 20 may have, for example, a rectangular shape, but is not limited to this. Elements 20A, 20B, 20C, and 20D may be formed on substrate 20. Elements 20A, 20B, 20C, and 20D may have different sizes. For example, the sizes increase in the order of element 20A, element 20B, element 20C, and element 20D. Elements 20A, 20B, 20C, and 20D may have different frequency bands and phase shift amounts of the radio waves they change.

[0016] Elements 20A, 20B, 20C, and 20D may be two-dimensionally arranged on substrate 20. Specifically, element 20A may be arranged in the center of substrate 20. Elements 20B, 20C, and 20D may be arranged around element 20A. In other words, radio wave focusing plate 12 may be configured by arranging multiple elements of different sizes concentrically. The focal position of radio wave focusing plate 12 can be adjusted by changing the design of the multiple elements of the radio wave focusing plate.

[0017] In this embodiment, the radio wave focusing plate 12 is not limited to one made of a metamaterial, and may be, for example, a dielectric lens or a Fresnel zone plate.

[0018] The terminal device 14 is installed indoors. The terminal device 14 is, for example, a communication device such as a smartphone that can communicate with the base station 10. The terminal device 14 may be a relay device that relays between the base station 10 and a communication device such as a smartphone. The terminal device 14 communicates with the base station 10 by receiving radio waves W3 that are drawn into the room 2 from the focal point F. Because the radio waves W3 diffuse within the room 2, the terminal device 14 can communicate with the base station 10 over a wide area of ​​the room 2.

[0019] As described above, in the first embodiment, radio waves W1 from the base station 10 are focused at the boundary between the indoor and outdoor areas as radio waves W2, thereby drawing radio waves W3 into the room. This allows the base station 10 and the terminal device 14 to communicate appropriately.

[0020] [Second embodiment] Next, a second embodiment will be described. In the present disclosure, the communication system 1 focuses radio waves at the boundary between the indoors and outdoors, thereby drawing radio waves into the room 2. In this case, it is preferable that the position where the radio waves are focused is a place where radio wave attenuation is relatively small.

[0021] The focal position of the radio wave focusing plate according to the second embodiment will be described with reference to Fig. 3. Fig. 3 is a diagram for explaining the focal position of the radio wave focusing plate according to the second embodiment.

[0022] FIG. 3 shows a wall 31, a plastic sash 32, and a windowpane 33 as the boundary between the indoors and outdoors of the room 2. The wall 31 is a portion that does not include, for example, metal members such as reinforcing bars. The plastic sash 32 is a plastic sash attached to the periphery of the windowpane 33. The windowpane 33 is a normal glass member. That is, the wall 31, the plastic sash 32, and the windowpane 33 are portions of the boundary between the indoors and outdoors of the room 2 where radio wave attenuation is relatively small. In the second embodiment, the radio wave focusing plate 12 is configured so that a focus F is located at the wall 31, the plastic sash 32, and the windowpane 33. This prevents radio waves W2 emitted from the radio wave focusing plate 12 from being attenuated at the boundary between the indoors and outdoors of the room 2.

[0023] As described above, in the second embodiment, radio waves W1 from the base station 10 are focused as radio waves W2 at a portion of the boundary between indoors and outdoors where radio wave attenuation is assumed to be small, thereby drawing radio waves W3 into the room 2. This makes it possible in the second embodiment to improve the power of the radio waves W3 received by the terminal device 14.

[0024] [Third embodiment] Next, a third embodiment will be described. In the present disclosure, the base station 10 communicates with the terminal device 14 using radio waves W3 drawn into the room 2. In this case, it is preferable that the terminal device 14 be installed in a position where it can easily receive the radio waves W3 drawn into the room 2.

[0025] The installation position of the terminal device according to the third embodiment will be described with reference to Fig. 4. Fig. 4 is a diagram for explaining the installation position of the terminal device according to the third embodiment.

[0026] As shown in Fig. 4, in the third embodiment, the terminal device 14 is preferably placed within an area 40 formed by lines connecting points on the periphery of the radio wave focusing plate 12 to the focal point F and extending the lines indoors. In the example shown in Fig. 4, for example, a plurality of points are set at predetermined intervals along the periphery of the radio wave focusing plate 12, and lines connecting each of the set points to the focal point F on the periphery are extended indoors, so that the terminal device 14 is placed within the area 40 formed by the plurality of lines. The area 40 is an area in which radio waves W3 are diffused. By placing the terminal device 14 within the area 40, the terminal device 14 can properly receive the radio waves W3.

[0027] As described above, in the third embodiment, the terminal device 14 is placed in the area 40 where the radio waves W3 drawn into the room 2 are diffused. This allows the base station 10 and the terminal device 14 to communicate appropriately in the third embodiment.

[0028] [Fourth embodiment] Next, a fourth embodiment will be described. In the present disclosure, radio waves W1 transmitted from a base station 10 are focused as radio waves W2 at the boundary between indoors and outdoors by a radio wave focusing plate 12, thereby drawing radio waves W3 into a room 2. In this case, if the size of the radio wave focusing plate 12 is small, there is a possibility that sufficient power cannot be obtained.

[0029] In the fourth embodiment, it is preferable that the radio wave focusing plate 12 is installed in a Fresnel zone, which is defined based on the straight-line distance between the base station 10 and the radio wave focusing plate 12, and the straight-line distance between the radio wave focusing plate 12 and the focus F.

[0030] A method for installing a radio wave focusing plate according to the fourth embodiment will be described with reference to Fig. 5. Fig. 5 is a diagram for explaining a method for installing a radio wave focusing plate according to the fourth embodiment.

[0031] In the example shown in FIG. 5, center point C indicates the center point of the radio wave focusing plate 12. Transmission point T indicates the position of the transmitting antenna of the base station 10 shown in FIG. 1. Reception point R indicates the position of the focal point F shown in FIG. 1. Reception point R' indicates a virtual focal position. Specifically, in the example shown in FIG. 5, the straight-line distance between center point C and reception point R is the same as the straight-line distance between center point C and reception point R'. When considering the path of radio waves from transmission point T to reception point R, passing through the radio wave focusing plate 12, the radio wave focusing plate 12 is installed in a region where the radio waves constructively interact. This enables this embodiment to obtain higher received power. In this embodiment, the region where the radio waves constructively interact is called an odd-order Fresnel zone, and the region where the radio waves destructively interact is called an even-order Fresnel zone.

[0032] As shown in Figure 5, consider a situation in which radio waves from a transmitting point T pass through a radio wave focusing plate 12 and reach a receiving point R. The linear distance between the transmitting point T and the center point C is d1. The linear distance between the receiving point R and the center point C is d2. Consider a plane P that is perpendicular to the line that connects the transmitting point T and the receiving point R', passing through the center point C. Now consider a circle on the plane P that is centered at the center point C and whose radius is defined by the following equation (1).

[0033]

number

[0034] In equation (1), n ​​is a natural number and λ is the wavelength of the radio wave.

[0035] In this embodiment, in equation (1), the annular portion ranging from radius Rn-1 to radius Rn is defined as the nth Fresnel zone. In the example shown in Fig. 5, a first Fresnel zone 50, a second Fresnel zone 52, a third Fresnel zone 54, and a fourth Fresnel zone 56 are shown. For example, the range of a circle with radius R1 is the first Fresnel zone 50. For example, the range of the annular portion between the circle with radius R1 and the circle with radius R2 is the second Fresnel zone 52.

[0036] The length of one side of the radio wave focusing plate 12 is preferably equal to or greater than the radius of the first Fresnel zone 50. Specifically, the length of one side of the radio wave focusing plate 12 is preferably equal to or greater than twice the radius of the first Fresnel zone 50. The radius of the nth Fresnel zone is also called the nth Fresnel radius. For example, by setting the size of the radio wave focusing plate 12 to be equal to or greater than twice the first Fresnel radius, the base station 10 and the terminal device 14 can communicate appropriately.

[0037] As described above, in the fourth embodiment, the area of ​​the radio wave focusing plate 12 is configured to be larger than the first Fresnel zone. This makes it possible to improve the power of the radio waves drawn into the room.

[0038] [Fifth embodiment] Next, a fifth embodiment will be described. In the present disclosure, radio waves W1 transmitted from a base station 10 are guided into a room 2 by a radio wave focusing plate 12. In this case, depending on the installation angle of the radio wave focusing plate 12, the radio waves W1 transmitted from the base station 10 may not be properly focused at a focal point F at the boundary between the indoors and outdoors, and sufficient power may not be obtained.

[0039] The installation angle of the radio wave focusing plate in the fifth embodiment will be described with reference to Fig. 6. Fig. 6 is a diagram for explaining the installation angle of the radio wave focusing plate in the fifth embodiment.

[0040] In Figure 6, arrow V1 indicates the direction of the perpendicular to the radio wave focusing plate 12, arrow V2 indicates the direction of incidence of radio waves W1 from the base station 10 to the radio wave focusing plate 12, and arrow V3 indicates the direction from the center point C of the radio wave focusing plate 12 toward the focal point F.

[0041] In this embodiment, the radio wave focusing plate 12 is installed so that when the arrow V1 is projected onto the plane formed by the arrows V2 and V3, the arrow V1 falls between the arrows V2 and V3. This allows the radio wave focusing plate 12 to appropriately focus the radio waves W1 transmitted by the base station 10 onto the focal point F.

[0042] As described above, in the fifth embodiment, the radio wave focusing plate 12 is installed so that the direction of the perpendicular to the radio wave focusing plate 12 is located between the incident direction of the radio waves W1 from the base station 10 to the radio wave focusing plate 12 and the direction from the center point C of the radio wave focusing plate 12 toward the focal point F. As a result, in the fifth embodiment, the radio waves W1 from the base station 10 can be appropriately focused at the focal point F, thereby improving the power of the radio waves drawn indoors.

[0043] [Sixth embodiment] Next, a sixth embodiment will be described. In the present disclosure, radio waves W1 transmitted by a base station 10 are drawn into a room 2 by a radio wave focusing plate 12. In this case, the range of radio waves W3 drawn into the room 2 from the radio wave focusing plate 12 is limited, so there is a possibility that proper communication will not be possible if the position of the terminal device 14 changes. In the sixth embodiment, multiple radio wave focusing plates 12 are installed to draw radio waves W1 into the room 2.

[0044] A method for installing a plurality of radio wave focusing plates according to the first example of the sixth embodiment will be described with reference to Fig. 7. Fig. 7 is a diagram for explaining a method for installing a plurality of radio wave focusing plates according to the first example of the sixth embodiment.

[0045] 7, the communication system 1A includes radio wave focusing plates 12-1, 12-2, and 12-3 as radio wave focusing plates 12. The number of radio wave focusing plates 12 included in the communication system 1A is not limited.

[0046] Radio wave focusing plate 12-1, radio wave focusing plate 12-2, and radio wave focusing plate 12-3 can be arranged side by side. Radio wave focusing plate 12-1 is configured to focus radio waves W1 received from base station 10 as radio waves W2-1 at a focal point F set on a structure 60 located between indoors and outdoors. Radio wave focusing plate 12-2 is configured to focus radio waves W1 received from base station 10 as radio waves W2-2 at the focal point F. Radio wave focusing plate 12-3 is configured to focus radio waves W1 received from base station 10 as radio waves W2-3 at the focal point F. In other words, radio wave focusing plate 12-1, radio wave focusing plate 12-2, and radio wave focusing plate 12-3 are configured to focus radio waves at the same focal point.

[0047] Radio wave W2-1 reaches indoors from focal point F as radio wave W3-1. Radio wave W2-2 reaches indoors from focal point F as radio wave W3-2. Radio wave W2-3 reaches indoors from focal point F as radio wave W3-3. This allows the communication system 1A to attract radio wave W1 transmitted by the base station 10 over a wide range.

[0048] A method for installing a plurality of radio wave focusing plates according to the second example of the sixth embodiment will be described with reference to Fig. 8. Fig. 8 is a diagram for explaining a method for installing a plurality of radio wave focusing plates according to the second example of the sixth embodiment.

[0049] As shown in Fig. 8, communication system 1B includes radio wave focusing plate 12-1, radio wave focusing plate 12-2, and radio wave focusing plate 12-3 as radio wave focusing plates 12. Communication system 1B differs from communication system 1A shown in Fig. 7 in that radio wave focusing plate 12-1, radio wave focusing plate 12-2, and radio wave focusing plate 12-3 are configured to focus radio waves at different focal points, respectively.

[0050] Radio wave focusing plate 12-1 is configured to focus radio waves W1 received from base station 10 as radio waves W2-1 at a focal point F1 set on structure 60. Radio wave focusing plate 12-2 is configured to focus radio waves W1 received from base station 10 as radio waves W2-2 at a focal point F2 set on structure 60. Radio wave focusing plate 12-3 is configured to focus radio waves W1 received from base station 10 as radio waves W2-3 at a focal point F3 set on structure 60.

[0051] Radio wave W2-1 reaches the indoors from focal point F1 as radio wave W3-1. Radio wave W2-2 reaches the indoors from focal point F2 as radio wave W3-2. Radio wave W2-3 reaches the indoors from focal point F3 as radio wave W3-3. This allows the communication system 1B to draw the radio wave W1 transmitted by the base station 10 indoors over a wide area.

[0052] As described above, in the sixth embodiment, the radio waves W1 from the base station 10 are drawn into a wide area indoors using a plurality of radio wave concentrating plates 12. As a result, in the sixth embodiment, even if the position of the terminal device 14 changes, the terminal device 14 can properly communicate with the base station 10.

[0053] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the contents of these embodiments. Furthermore, the above-described components include those that can be easily imagined by a person skilled in the art, those that are substantially the same, and those that are within the so-called equivalent range. Furthermore, the above-described components can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the components can be made without departing from the spirit of the above-described embodiments. [Explanation of symbols]

[0054] 1,1A,1B communication system 10 base station 12,12-1,12-2,12-3 Radio wave focusing plate 14 Terminal Equipment 20 PCB 20A, 20B, 20C, 20D elements 31 Wall 32 Resin sash 33 Window Glass 50 First Fresnel Zone 52 Second Fresnel Zone 54 Third Fresnel Zone 56 4th Fresnel Zone 60 Structures

Claims

1. a base station installed outdoors and configured to transmit and receive radio waves; a radio wave focusing plate configured to receive the radio wave transmitted from the base station and emit the radio wave with the boundary between the indoors and outdoors as a focal point; a terminal device configured to receive the radio waves emitted from the radio wave focusing plate and communicate with the base station; a communication system including:

2. the radio wave focusing plate is configured to focus the radio waves at a position on the boundary between the outdoor area and the indoor area where attenuation of the radio waves is relatively small. The communication system of claim 1 .

3. the radio wave focusing plate is configured to converge the radio waves onto any one of a window glass, a resin sash attached to the outer periphery of the window glass, or a wall portion not including a metal member, which is provided at the boundary between the outdoors and the indoors. The communication system according to claim 2 .

4. the terminal device is installed indoors in an area formed by a straight line extending from a point on the periphery of the radio wave focusing plate to the focus; 3. A communication system according to claim 1 or 2.

5. a length of one side of the radio wave focusing plate is equal to or greater than a radius of a first Fresnel zone defined by a positional relationship between the base station, the radio wave focusing plate, and the terminal device; 3. A communication system according to claim 1 or 2.

6. The radio wave focusing plate is installed so that the direction of a perpendicular line to the radio wave focusing plate is between the direction of incidence of the radio waves on the radio wave focusing plate and the direction from the center of the radio wave focusing plate toward the focal point.

3. A communication system according to claim 1 or 2.

7. A plurality of the radio wave focusing plates are included.

3. A communication system according to claim 1 or 2.

8. The plurality of radio wave focusing plates are configured to have the same focal position.

8. The communication system according to claim 7.

9. The plurality of radio wave focusing plates are configured to have different focal positions.

8. The communication system according to claim 7.

10. A radio wave receiving device configured to receive radio waves transmitted from outdoors and emit the radio waves with the boundary between the outdoors and indoors as a focal point. Radio wave focusing plate.

Images