JP2021114647A - Electric wave reflection device - Google Patents

Abstract

To provide an electric wave reflection device by which the communication quality in the over-the-horizon area can be improved easily.SOLUTION: An electric wave reflection device includes a meta-surface substrate, a dielectric substrate disposed facing the meta-surface substrate, and an adjustment unit that adjusts the distance between the meta-surface substrate and the dielectric substrate.SELECTED DRAWING: Figure 6

Description

The present invention relates to a radio wave reflecting device.

Radio waves in the millimeter wave band have high straightness, and communication quality deteriorates significantly in areas outside the line of sight from the base station. Therefore, in recent years, a reflector using a metasurface has been attracting attention. Conventionally, a radio wave reflecting device that controls the reflectance and suppresses the interference of radio waves has been disclosed (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2017-175342

However, the reflector using the conventional metasurface is designed according to the installation location. Therefore, the reflector using the conventional meta-surface requires a design for each installation location, and it takes time and effort to improve the communication quality in the non-line-of-sight area.

One of the purposes of the present disclosure is to easily improve the communication quality in the non-line-of-sight area.

The radio wave reflecting device of the present disclosure includes a metasurface substrate, a dielectric substrate arranged to face the metasurface substrate, an adjusting unit for adjusting the distance between the metasurface substrate and the dielectric substrate, and an adjusting unit. Has.

According to the present disclosure, the communication quality in the non-line-of-sight area can be easily improved.

It is a perspective view which showed an example of a metal reflector. It is a perspective view which showed an example of the meta-surface reflector. It is a figure which showed an example of the wireless communication system which applied the radio wave reflection device which concerns on embodiment. It is a perspective view which showed an example of the radio wave reflecting device. It is a perspective view which showed an example of the dielectric substrate of the radio wave reflector. It is a perspective view which showed an example of the meta surface substrate of a radio wave reflector. It is a figure which showed the pattern example of a unit cell. It is a figure which showed the pattern example of a unit cell. It is a figure which showed the pattern example of a unit cell. It is a figure which showed the pattern example of a unit cell. It is a side sectional view which showed an example of the radio wave reflecting device. It is a side sectional view which showed another example of the radio wave reflector. It is a figure explaining an example of the reflectance and the transmittance of a radio wave reflector. It is a figure explaining an example of the reflectance and the transmittance of a radio wave reflector. It is a figure explaining an example of the reflectance and the transmittance of a radio wave reflector. It is a figure explaining an example of the reflectance and the transmittance of a radio wave reflector. It is a figure which showed the application example of the radio wave reflector. It is a figure which showed the application example of the radio wave reflector. It is a figure which showed an example of the hardware composition of the control part of a radio wave reflector.

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

In wireless communication systems after 5G, high-speed, large-capacity, and low-delay wireless communication is realized by using radio waves in the millimeter wave band. Radio waves in the millimeter wave band have high straightness, and communication quality deteriorates significantly in areas outside the line of sight from the base station. 5G is an abbreviation for 5th generation mobile communication system.

As a method of suppressing deterioration of communication quality in a non-line-of-sight area, the use of a reflector that reflects radio waves is considered. The reflector, for example, reflects the radio waves output from the base station to the non-line-of-sight area to improve the communication quality of the terminal in the non-line-of-sight area.

FIG. 1 is a perspective view showing an example of the metal reflector 1. The metal reflector 1 has a dielectric substrate. A metal film is uniformly formed on the dielectric substrate.

The metal reflector 1 has, for example, the following three features. The incident wave may be paraphrased as an incoming wave.
1. 1. The reflection angle of the reflected wave of the metal reflector 1 is determined based on the incident angle of the incident wave.
2. The beam width of the reflected wave of the metal reflector 1 is determined based on the size of the metal reflector 1. For example, the larger the size of the metal reflector 1, the narrower the beam width of the reflected wave.
3. 3. Radio waves do not pass (substantially do not pass) on the side of the metal reflector 1 opposite to the reflecting surface.

The metal reflector 1 has the following two problems, for example.
1. 1. Based on the above feature 1, the metal reflector 1 is limited in its posture at the time of installation (for example, the surface angle of the metal reflector 1). Therefore, the installation location of the metal reflector 1 is limited. For example, a base station is installed on the roof of a building. The non-line-of-sight area is set on the ground below the base station (including near the ground). The metal reflector 1 is installed at substantially the same height as the non-line-of-sight area. In this case, the surface of the metal reflector 1 is directed upward. Therefore, the installation location of the metal reflector 1 is limited to a location where the metal reflector 1 can be installed at an angle (upward).
2. In order for the metal reflector 1 to efficiently reflect radio waves, the size of the metal reflector 1 is increased. When the size of the metal reflector 1 is increased, the beam width of the reflected wave becomes narrower based on the above feature 2. When the beam width becomes narrow, it becomes difficult to form a wide communication area in the non-line-of-sight area.

Due to the above two issues, the use of a reflector using a metasurface is considered.

FIG. 2 is a perspective view showing an example of the meta-surface reflector 2. The meta-surface reflector 2 has a dielectric substrate. A plurality of unit cells having the same shape are formed on the dielectric substrate. The unit cell is a metal film pattern. The size (length x width) of the unit cell may differ depending on the position on the dielectric substrate.

In the meta-surface reflector 2, the reflection angle and beam width of the reflected wave can be determined based on the pattern shape of the unit cell.

Therefore, in the metasurface reflector 2, the limitation of the installation location can be relaxed by changing the reflection angle of the reflected wave based on the pattern shape of the unit cell without tilting the entire metasurface reflector 2.

Further, in the meta-surface reflector 2, a wide communication area can be easily formed by forming a reflected wave having a desired beam width based on the pattern shape of the unit cell.

The reflection angle and beam width of the reflected wave on the meta-surface reflector 2 are, for example, the position of the base station, the position of the non-line-of-sight area for improving communication quality, the size of the non-line-of-sight area for improving communication quality, and the meta-surface reflection. It is determined based on the installation location of the plate 2. The pattern shape of the unit cell is designed to satisfy the determined reflection angle and beam width of the reflected wave. The unit cell is formed on a dielectric substrate based on the design.

The reflection angle and beam width of the reflected wave required for the metasurface reflector 2 differ depending on the installation location of the metasurface reflector 2. Therefore, since the meta-surface reflector 2 is designed for each installation location according to the installation location, it takes time and effort to improve the communication quality. Further, since the meta-surface reflector 2 is designed for each installation location according to the installation location, it is costly. Further, since the metasurface reflector 2 does not transmit radio waves on the side opposite to the reflective surface, similarly to the feature 3 of the metal reflector 1, it is located in the area opposite to the reflective surface of the metasurface reflector 2. The radio wave of the base station does not reach. The radio wave reflecting device described below solves the problem of the meta-surface reflector 2.

FIG. 3 is a diagram showing an example of a wireless communication system 10 to which the radio wave reflecting device 12 according to the embodiment is applied. As shown in FIG. 3, the wireless communication system 10 includes a base station 11, a radio wave reflecting device 12, and a terminal 13. Area A1 indicates a non-line-of-sight area.

The base station 11 is installed on the roof of a building such as a building or a condominium, for example. The radio wave reflecting device 12 is installed near the ground, for example. The terminal 13 located in the area A1 communicates with the base station 11 via the radio wave reflecting device 12.

FIG. 3 shows an example of the communication speed of the terminal 13 when the radio wave reflecting device 12 is present and the communication speed of the terminal 13 when the radio wave reflecting device 12 is not present at points P1 to P3 in the area A1. .. As shown in FIG. 3, the communication speed of the terminal 13 when the radio wave reflecting device 12 is present is higher than the communication speed of the terminal 13 when the radio wave reflecting device 12 is not present. Further, the communication speed of the terminal 13 decreases as the distance from the radio wave reflecting device 12 increases.

The installation location of the base station 11 and the radio wave reflecting device 12 is not limited to the example of FIG. For example, the base station 11 and the radio wave reflecting device 12 may be installed indoors. Further, the setting location of the area A1 is not limited to the example of FIG. For example, the area A1 may be set indoors.

FIG. 4A is a perspective view showing an example of the radio wave reflecting device 12. FIG. 4B is a perspective view showing an example of the dielectric substrate 21 of the radio wave reflecting device 12. FIG. 4C is a perspective view showing an example of the meta surface substrate 22 of the radio wave reflecting device 12.

The radio wave reflecting device 12 includes a dielectric substrate 21 and a metasurface substrate 22. The dielectric substrate 21 and the metasurface substrate 22 have, for example, a quadrangular shape. Although not shown in FIGS. 4A to 4C, the radio wave reflecting device 12 has a connecting member that connects the dielectric substrate 21 and the metasurface substrate 22 (see, for example, FIGS. 6 and 7). Further, the radio wave reflecting device 12 has a control unit (see, for example, FIG. 11).

As shown in FIG. 4A, the dielectric substrate 21 and the metasurface substrate 22 are arranged so as to face each other. The radio waves of the base station 11 are incident on the surface of the metasurface substrate 22 opposite to the surface facing the dielectric substrate 21. For example, the radio wave of the base station 11 is incident from the direction shown by the arrow A11 in FIG. 4A.

The radio wave reflecting device 12 changes the distance between the dielectric substrate 21 and the metasurface substrate 22 to change the reflectance and transmittance of radio waves. For example, the radio wave reflecting device 12 changes the distance D between the surfaces of the dielectric substrate 21 and the metasurface substrate 22 facing each other, as shown in FIG. 4A, and changes the reflectance and transmittance of the radio waves. The distance D is variable, for example, in the range of 0 μm or more and 500 μm or less when the frequency of the incident radio wave is 28 GHz. The distance between the dielectric substrate 21 and the metasurface substrate 22 may be rephrased as the gap between the dielectric substrate 21 and the metasurface substrate 22.

The dielectric substrate 21 and the metasurface substrate 22 may be formed using a transparent dielectric material. For example, the dielectric substrate 21 and the metasurface substrate 22 may be formed using a material of glass, Teflon®, or an acrylic resin. Further, the dielectric substrate 21 and the metasurface substrate 22 may be formed by using a printed circuit board. When the dielectric substrate 21 and the metasurface substrate 22 are formed by using a transparent dielectric material, the radio wave reflecting device 12 has less influence on the landscape.

The dielectric substrate 21 and the metasurface substrate 22 may be formed of the same material or may be made of different materials.

When different materials are used for the dielectric substrate 21 and the metasurface substrate 22, it is preferable to select the material so that the dielectric constant of the dielectric substrate 21 is larger than the dielectric constant of the metasurface substrate 22. When the dielectric constant of the dielectric substrate 21 is made larger than the dielectric constant of the metasurface substrate 22, the reflectance and transmittance of the radio wave reflecting device 12 change significantly with respect to a small amount of change in the distance D. That is, the reflectance and transmittance responses to the distance D are improved.

The size of the dielectric substrate 21 and the metasurface substrate 22 may be determined based on the distance between the base station 11 and the radio wave reflecting device 12 and the wavelength of the incident radio wave. For example, the size (length x width) of the dielectric substrate 21 and the metasurface substrate 22 depends on the distance between the base station 11 and the radio wave reflecting device 12, but is 10 times or more the wavelength of the incident radio wave. It is desirable to decide.

No metal film is formed on the dielectric substrate 21. On the other hand, as shown in FIG. 4C, a plurality of unit cells 22a are formed on the metasurface substrate 22. The unit cell 22a is a metal film pattern.

The size of the unit cell 22a may differ depending on the position on the dielectric substrate. The unit cell 22a may have the same shape, or may have a different shape depending on the position on the dielectric substrate. When the shape of the unit cell 22a differs depending on the position on the dielectric substrate, for example, the width of the gap described in FIGS. 5A-5D below may differ depending on the position on the dielectric substrate.

The unit cell 22a is formed on the surface of the metasurface substrate 22 facing the dielectric substrate 21. The size (length x width) of the unit cell 22a is set to, for example, 1/10 or more and 1/5 or less of the wavelength of the incident radio wave. In order to form a smoother wavefront of the reflected wave, the size of the unit cell 22a is preferably smaller.

5A-5D is a diagram showing a pattern example of the unit cell 22a. The unit cell 22a formed on the meta-surface substrate 22 may have the pattern shape shown in FIGS. 5A-5D.

The unit cell 22a has a pattern shape in which the electric field is locally concentrated. For example, the unit cell 22a has a gap G1 as shown in FIGS. 5A-5D. The electric field is locally concentrated in the gap G1 of the unit cell 22a. With this configuration, the reflectance and transmittance of the radio wave reflecting device 12 change greatly with respect to a small amount of change in the distance D.

The pattern shape of the unit cell 22a formed on the meta-surface substrate 22 may be one type or a combination of two or more types. For example, the unit cell 22a formed on the meta-surface substrate 22 may be a combination of two or more of the pattern shapes shown in FIGS. 5A-5D.

The radio wave reflecting device 12 may be referred to as a reflector or a non-powered repeater. The dielectric substrate 21 may be referred to as a movable substrate. The metasurface substrate 22 may be referred to as a metasurface reflector or may be referred to as a metasurface.

FIG. 6 is a side sectional view showing an example of the radio wave reflecting device 12. In FIG. 6, the same components as those in FIGS. 4A-4C are designated by the same reference numerals.

As shown in FIG. 6, the radio wave reflecting device 12 has a connecting member 31. The connecting members 31 are provided at the four corners of the dielectric substrate 21 and the metasurface substrate 22, for example, and connect the dielectric substrate 21 and the metasurface substrate 22.

The connecting member 31 has an adjusting portion 32. The adjusting unit 32 may be, for example, a piezoelectric actuator. The adjusting unit 32 expands and contracts according to the control of the control unit, and adjusts (changes) the distance between the dielectric substrate 21 and the metasurface substrate 22. The adjusting unit may be paraphrased as an actuator.

In the example of FIG. 6, when the adjusting portion 32 is extended, the dielectric substrate 21 is separated from the metasurface substrate 22, and the distance between the dielectric substrate 21 and the metasurface substrate 22 is increased. When the adjusting portion 32 shrinks, the dielectric substrate 21 approaches the metasurface substrate 22, and the distance between the dielectric substrate 21 and the metasurface substrate 22 decreases.

The adjusting portions 32 of the four connecting members 31 provided at the four corners of the dielectric substrate 21 and the metasurface substrate 22 may be expanded and contracted with the same size, or each may be expanded and contracted with different sizes. .. The adjusting portions 32 of the four connecting members 31 provided at the four corners of the dielectric substrate 21 and the metasurface substrate 22 may be partially elongated and the rest may be contracted.

Based on the operation of the adjusting unit 32, the dielectric substrate 21 and the metasurface substrate 22 can be in a parallel state. Further, the distance between the dielectric substrate 21 and the metasurface substrate 22 can be changed in a parallel state.

Further, based on the operation of the adjusting unit 32, the dielectric substrate 21 and the metasurface substrate 22 can be in a non-parallel state (for example, the dielectric substrate 21 is tilted with respect to the metasurface substrate 22). can). Further, the distance between the dielectric substrate 21 and the metasurface substrate 22 can be changed in a non-parallel state.

FIG. 7 is a side sectional view showing another example of the radio wave reflecting device 12. In FIG. 7, the same components as those in FIGS. 4A-4C are designated by the same reference numerals.

As shown in FIG. 7, the radio wave reflecting device 12 has a connecting member 41. The connecting members 41 are provided at the four corners of the dielectric substrate 21 and the metasurface substrate 22, for example, and connect the dielectric substrate 21 and the metasurface substrate 22.

The connecting member 41 has an adjusting portion 42. The adjusting unit 42 may be, for example, a piezoelectric actuator. The adjusting unit 42 expands and contracts according to the control of the control unit to adjust the distance between the dielectric substrate 21 and the metasurface substrate 22.

In the example of FIG. 7, when the adjusting portion 42 is extended, the dielectric substrate 21 approaches the metasurface substrate 22, and the distance between the dielectric substrate 21 and the metasurface substrate 22 becomes smaller. When the adjusting portion 42 contracts, the dielectric substrate 21 separates from the metasurface substrate 22, and the distance between the dielectric substrate 21 and the metasurface substrate 22 increases.

The adjusting portions 42 of the four connecting members 41 provided at the four corners of the dielectric substrate 21 and the metasurface substrate 22 may be expanded and contracted with the same size, or each may be expanded and contracted with different sizes. .. The adjusting portions 42 of the four connecting members 41 provided at the four corners of the dielectric substrate 21 and the metasurface substrate 22 may be partially stretched and the rest may be shrunk.

Based on the operation of the adjusting unit 42, the dielectric substrate 21 and the metasurface substrate 22 can be in a parallel state. Further, the distance between the dielectric substrate 21 and the metasurface substrate 22 can be changed in a parallel state.

Further, the dielectric substrate 21 and the metasurface substrate 22 can be in a non-parallel state based on the operation of the adjusting unit 42. Further, the distance between the dielectric substrate 21 and the metasurface substrate 22 can be changed in a non-parallel state.

The connecting members 31 and 41 may be provided scattered around the dielectric substrate 21 and the metasurface substrate 22.

Further, the adjusting units 32 and 42 are not limited to the piezoelectric actuator. The adjusting units 32 and 42 may be any as long as they can adjust the distance between the dielectric substrate 21 and the metasurface substrate 22. For example, the adjusting units 32 and 42 may be tubes for taking in and out air.

Further, the radio wave reflecting device 12 may have an operating device that accepts the user's operation. The operating device may be, for example, a dial.

The control unit of the radio wave reflecting device 12 controls the adjusting units 32 and 42 as the dial rotates, and adjusts the distance between the dielectric substrate 21 and the metasurface substrate 22. For example, the control unit of the radio wave reflecting device 12 expands and contracts the distance between the dielectric substrate 21 and the metasurface substrate 22 based on the rotation direction of the dial. Further, the control unit of the radio wave reflecting device 12 controls the amount of expansion and contraction between the dielectric substrate 21 and the metasurface substrate 22 based on the amount of rotation of the dial.

Further, the radio wave reflecting device 12 may have an input device that accepts a user's operation. The input device may be, for example, a key device.

The control unit of the radio wave reflecting device 12 may adjust the distance between the dielectric substrate 21 and the metasurface substrate 22 according to the set time and the set distance input to the input device. For example, the control unit of the radio wave reflecting device 12 sets the distance between the dielectric substrate 21 and the metasurface substrate 22 as the first set distance in the first set time. The control unit of the radio wave reflecting device 12 sets the distance between the dielectric substrate 21 and the metasurface substrate 22 as the second set distance in the second set time.

Further, the control unit of the radio wave reflecting device 12 may communicate with one or both of the base station 11 and the terminal 13 to acquire the position of the terminal 13. The control unit of the radio wave reflecting device 12 may adjust the distance between the dielectric substrate 21 and the metasurface substrate 22 based on the acquired position of the terminal 13.

8A-8D are diagrams illustrating an example of the reflectance and transmittance of the radio wave reflecting device 12. 8A-8D show the dielectric substrate 21 and the metasurface substrate 22. Arrow A21 shown in FIGS. 8A-8D indicates an incident wave of radio waves. Arrow A22 indicates a reflected wave of radio waves. Arrow A23 indicates a transmitted wave of radio waves.

8A, 8B, and 8C show graphs of the transmittance of the radio wave reflecting device 12 with respect to the frequency. The operating frequencies shown in FIGS. 8A, 8B, and 8C are frequencies of radio waves incident on the radio wave reflecting device 12.

As shown in the graphs of FIGS. 8A, 8B, and 8C, the transmittance of the radio wave reflecting device 12 is the smallest at the resonance frequency. In other words, the reflectance of the radio wave reflecting device 12 is the largest at the resonance frequency of the transmittance.

The resonance frequency of the transmittance of the radio wave reflecting device 12 changes according to the distance between the dielectric substrate 21 and the metasurface substrate 22. For example, as the distance between the dielectric substrate 21 and the metasurface substrate 22 decreases, the resonance frequency of the transmittance of the radio wave reflecting device 12 decreases.

FIG. 8A shows a graph of the transmittance of the radio wave reflecting device 12 when the distance between the dielectric substrate 21 and the metasurface substrate 22 is D1. When the distance between the dielectric substrate 21 and the metasurface substrate 22 is D1, the resonance frequency of the transmittance of the radio wave reflecting device 12 overlaps with the operating frequency.

That is, when the distance between the dielectric substrate 21 and the metasurface substrate 22 is D1, the transmittance of the radio wave reflecting device 12 is the smallest. In other words, when the distance between the dielectric substrate 21 and the metasurface substrate 22 is D1, the reflectance of the radio wave reflecting device 12 is the largest.

The resonance frequency of the transmittance when the distance between the dielectric substrate 21 and the metasurface substrate 22 is D1 is adjusted to the operating frequency based on, for example, the pattern shape and size of the unit cell 22a.

FIG. 8B shows the transmission of the radio wave reflecting device 12 when the distance between the dielectric substrate 21 and the metasurface substrate 22 is 0 (when the dielectric substrate 21 and the metasurface substrate 22 are in contact with each other). A graph of the rate is shown. When the distance between the dielectric substrate 21 and the metasurface substrate 22 is 0, the resonance frequency of the transmittance of the radio wave reflecting device 12 shifts to a frequency lower than the operating frequency.

That is, when the distance between the dielectric substrate 21 and the metasurface substrate 22 is 0, the transmittance of the radio wave reflecting device 12 becomes large. In other words, the reflectance of the radio wave reflecting device 12 becomes small.

When the distance between the dielectric substrate 21 and the metasurface substrate 22 is 0, the transmittance can be adjusted to be the largest based on the pattern shape and size of the unit cell 22a.

FIG. 8C shows a graph of the transmittance of the radio wave reflecting device 12 when the distance between the dielectric substrate 21 and the metasurface substrate 22 is greater than 0 and smaller than D1 (when the distance is D2). When the distance between the dielectric substrate 21 and the metasurface substrate 22 is D2, the resonance frequency of the transmittance of the radio wave reflecting device 12 is between the resonance frequency shown in FIG. 8A and the resonance frequency shown in FIG. 8B. Located in.

Therefore, the radio wave reflecting device 12 can transmit a part of the incident radio wave and reflect a part of the radio wave. The state in which the radio wave reflecting device 12 transmits a part of the radio wave and reflects a part of the radio wave may be referred to as scattering.

FIG. 8D shows a state in which the dielectric substrate 21 is tilted with respect to the metasurface substrate 22. When the dielectric substrate 21 is tilted with respect to the metasurface substrate 22, the reflected wave of the radio wave reflecting device 12 is deflected.

When the dielectric substrate 21 is tilted with respect to the metasurface substrate 22, the radio wave reflecting device 12 can also deflect the transmitted radio waves.

FIG. 9 is a diagram showing an application example of the radio wave reflecting device 12. FIG. 9 shows the base station 11 and the radio wave reflecting devices 12a to 12c. The radio wave reflecting devices 12a to 12c correspond to the radio wave reflecting device 12.

The radio wave reflecting device 12a is set to transmit and deflect the radio waves of the base station 11 based on, for example, the above-mentioned dial operation. With this configuration, the radio wave of the base station 11 reaches the terminal of the user U1.

The radio wave reflecting device 12b is set to reflect and deflect the radio wave of the base station 11 based on, for example, the above-mentioned dial operation. With this configuration, the radio wave of the base station 11 reaches the terminal of the user U2.

The radio wave reflecting device 12c transmits or deflects the radio wave of the base station 11 based on the acquisition of the terminal position described above, for example. For example, the radio wave reflecting device 12c acquires the position of the terminal of the user U3. The radio wave reflecting device 12c transmits or deflects the radio wave of the base station 11 based on the acquired position of the terminal of the user U3. With this configuration, the radio wave reflecting device 12c suppresses interference with the direct wave that reaches the terminal of the user U3 from the base station 11.

FIG. 10 is a diagram showing an application example of the radio wave reflecting device 12. FIG. 10 shows the base station 11 and the radio wave reflecting devices 12a to 12c. The radio wave reflecting devices 12a to 12c correspond to the radio wave reflecting device 12.

The radio wave reflecting devices 12a and 12b transmit the radio waves of the base station 11 during the daytime on weekdays, for example, based on the set time and the set distance described above. With this configuration, the terminal in the office shown in FIG. 10 can communicate with the base station 11 during the daytime on weekdays.

Further, the radio wave reflecting devices 12a and 12b reflect the radio waves of the base station 11 on weekday nights and holidays, for example, based on the above-mentioned set time and set distance. With this configuration, the terminal in the office shown in FIG. 10 is prohibited from communicating with the base station 11 on weekday nights and holidays.

The radio wave reflecting device 12c is set to reflect the radio waves of the base station 11 based on, for example, the above-mentioned dial operation. With this configuration, the terminal in the security area is prohibited from communicating with the base station 11.

As described above, the radio wave reflecting device 12 determines the distance between the metasurface substrate 22, the dielectric substrate 21 arranged to face the metasurface substrate 22, and the metasurface substrate 22 and the dielectric substrate 21. It has an adjusting unit 32 (42) for adjusting.

With this configuration, the radio wave reflecting device 12 does not have to be designed according to the installation location for each installation location, and the communication quality in the non-line-of-sight area can be easily improved. For example, after installing the radio wave reflecting device 12, the user can dynamically adjust the distance between the dielectric substrate 21 and the metasurface substrate 22 to improve the communication quality in the non-line-of-sight area.

Further, the radio wave reflecting device 12 does not have to be designed according to the installation location for each installation location, and the cost can be reduced.

Further, since the radio wave reflecting device 12 transmits radio waves, the radio waves of the base station 11 can reach the area opposite to the reflecting surface of the radio wave reflecting device 12.

Further, the radio wave reflecting device 12 does not emit radio waves and improves the communication quality in the non-line-of-sight area, so that a license is not required.

Further, the radio wave reflecting device 12 can easily have a high frequency. Further, the area of the radio wave reflecting device 12 can be easily increased.

The present disclosure has been described above.

<Hardware configuration, etc.>
The control unit of the radio wave reflecting device 12 shows a block of functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Further, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized by using one device that is physically or logically connected, or directly or indirectly (for example, by two or more devices that are physically or logically separated). , Wired, wireless, etc.) and may be realized using these plurality of devices. The functional block may be realized by combining the software with the one device or the plurality of devices.

Functions include judgment, decision, judgment, calculation, calculation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, solution, selection, selection, establishment, comparison, assumption, expectation, and assumption. There are broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, assigning, etc., but only these. I can't. For example, a functional block (component) that functions transmission is called a transmitting unit or a transmitter. As described above, the method of realizing each of them is not particularly limited.

FIG. 11 is a diagram showing an example of the hardware configuration of the control unit of the radio wave reflecting device 12. The above-mentioned control unit may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input unit 1005, an output unit 1006, a bus 1007, and the like.

In the following description, the word "device" can be read as a circuit, a device, a unit, or the like. The hardware configuration of the control unit may be configured to include one or more of the devices shown in the figure, or may be configured not to include some of the devices.

For each function in the control unit, by loading predetermined software (program) on the hardware such as the processor 1001 and the memory 1002, the processor 1001 performs an calculation and controls the communication by the communication device 1004, or the memory 1002 and the memory 1002. It is realized by controlling at least one of reading and writing of data in the storage 1003.

Processor 1001 operates, for example, an operating system to control the entire computer. The processor 1001 may be configured by a central processing unit (CPU) including an interface with a peripheral device, a control device, an arithmetic unit, a register, and the like.

Further, the processor 1001 reads a program (program code), a software module, data, and the like from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes according to these. As the program, a program that causes a computer to execute at least a part of the operations described in the above-described embodiment is used. For example, the control unit may be realized by a control program stored in the memory 1002 and operating in the processor 1001, and may be realized in the same manner for other functional blocks. Although the above-mentioned various processes have been described as being executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. Processor 1001 may be implemented by one or more chips. The program may be transmitted from the network via a telecommunication line.

The memory 1002 is a computer-readable recording medium, and is composed of at least one such as a ROM (Read Only Memory), an EPROM (Erasable Programmable ROM), an EEPROM (Electrically Erasable Programmable ROM), and a RAM (Random Access Memory). May be done. The memory 1002 may be referred to as a register, a cache, a main memory (main storage device), or the like. The memory 1002 can store a program (program code), a software module, or the like that can be executed to implement the wireless communication method according to the embodiment of the present disclosure.

The storage 1003 is a computer-readable recording medium, for example, an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, an optical magnetic disk (for example, a compact disk, a digital versatile disk, a Blu-ray). It may consist of at least one (registered trademark) disk), smart card, flash memory (eg, card, stick, key drive), floppy (registered trademark) disk, magnetic strip, and the like. The storage 1003 may be referred to as an auxiliary storage device. The storage medium described above may be, for example, a database, server or other suitable medium containing at least one of the memory 1002 and the storage 1003.

The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, or the like. The communication device 1004 includes, for example, a high frequency switch, a duplexer, a filter, a frequency synthesizer, and the like in order to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). It may be composed of.

An input device (for example, a key device, a mouse, a microphone, a switch, a button, a sensor, etc.) and an operation device (for example, a dial) for receiving an input from the outside are connected to the input unit 1005. An output device (for example, a display, a speaker, an LED lamp, etc.) is connected to the output unit 1006. The input device and the output device connected to the input unit 1005 and the output unit 1006 may be an integrated device (for example, a touch panel).

Further, each device such as the processor 1001 and the memory 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be configured by using a single bus, or may be configured by using a different bus for each device.

In addition, the control unit includes hardware such as a microprocessor, a digital signal processor (DSP: Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array). The hardware may realize a part or all of each functional block. For example, processor 1001 may be implemented using at least one of these hardware.

<Information notification, signaling>
The notification of information is not limited to the embodiments / embodiments described in the present disclosure, and may be performed by other methods. For example, information notification includes physical layer signaling (for example, DCI (Downlink Control Information), UCI (Uplink Control Information)), upper layer signaling (for example, RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling, etc. It may be carried out by broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals or a combination thereof. RRC signaling may also be referred to as an RRC message, for example, RRC. It may be a connection setup (RRC Connection Setup) message, an RRC connection reconfiguration (RRC Connection Reconfiguration) message, or the like.

<Applicable system>
Each aspect / embodiment described in the present disclosure includes LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), and 5G (5th generation mobile communication). system), FRA (Future Radio Access), NR (new Radio), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)) )), IEEE 802.16 (WiMAX®), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth®, and other systems that utilize and extend based on these. It may be applied to at least one of the next generation systems. Further, a plurality of systems may be applied in combination (for example, a combination of at least one of LTE and LTE-A and 5G).

<Processing procedure, etc.>
The order of the processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in the present disclosure may be changed as long as there is no contradiction. For example, the methods described in the present disclosure present elements of various steps using exemplary order, and are not limited to the particular order presented.

<Operation of base station>
In some cases, the specific operation performed by the base station in the present disclosure may be performed by its upper node. In a network consisting of one or more network nodes having a base station, various operations performed for communication with the terminal are performed by the base station and other network nodes other than the base station (for example, MME or). It is clear that it can be done by at least one of (but not limited to, S-GW, etc.). Although the case where there is one network node other than the base station is illustrated above, it may be a combination of a plurality of other network nodes (for example, MME and S-GW).

<Direction of input / output>
Information and the like (* see the item "Information, signal") can be output from the upper layer (or lower layer) to the lower layer (or upper layer). Input / output may be performed via a plurality of network nodes.

<Handling of input / output information, etc.>
The input / output information and the like may be stored in a specific location (for example, a memory), or may be managed using a management table. The input / output information and the like can be overwritten, updated, or added. The output information and the like may be deleted. The input information or the like may be transmitted to another device.

<Judgment method>
The determination may be made by a value represented by 1 bit (0 or 1), by a boolean value (Boolean: true or false), or by comparing numerical values (for example, a predetermined value). It may be done by comparison with the value).

<Variations of modes, etc.>
Each aspect / embodiment described in the present disclosure may be used alone, in combination, or switched with execution. Further, the notification of predetermined information (for example, the notification of "being X") is not limited to the explicit one, but is performed implicitly (for example, the notification of the predetermined information is not performed). May be good.

Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described in the present disclosure. The present disclosure may be implemented as an amendment or modification without departing from the purpose and scope of the present disclosure, which is determined by the description of the scope of claims. Therefore, the description of the present disclosure is for the purpose of exemplary explanation and does not have any limiting meaning to the present disclosure.

<Software>
Software, whether referred to as software, firmware, middleware, microcode, hardware description language, or by any other name, is an instruction, instruction set, code, code segment, program code, program, subprogram, software module. , Applications, software applications, software packages, routines, subroutines, objects, executables, execution threads, procedures, features, etc. should be broadly interpreted.

Further, software, instructions, information and the like may be transmitted and received via a transmission medium. For example, a website where the software uses at least one of wired technology (coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), etc.) and wireless technology (infrared, microwave, etc.). When transmitted from a server, or other remote source, at least one of these wired and wireless technologies is included within the definition of transmission medium.

<Information, signals>
The information, signals, etc. described in the present disclosure may be represented using any of a variety of different techniques. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description are voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any of these. It may be represented by a combination of.

The terms described in the present disclosure and the terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Also, the signal may be a message. Further, the component carrier (CC: Component Carrier) may be referred to as a carrier frequency, a cell, a frequency carrier, or the like.

<"System", "Network">
The terms "system" and "network" used in this disclosure are used interchangeably.

<Parameter, channel name>
In addition, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, relative values from predetermined values, or using other corresponding information. It may be represented. For example, the radio resource may be one indicated by an index.

The names used for the above parameters are not limited in any way. Further, mathematical formulas and the like using these parameters may differ from those explicitly disclosed in this disclosure. Since the various channels (eg, PUCCH, PDCCH, etc.) and information elements can be identified by any suitable name, the various names assigned to these various channels and information elements are in any respect limited names. is not it.

<Base station>
In the present disclosure, "Base Station (BS)", "Wireless Base Station", "Fixed Station", "NodeB", "eNodeB (eNB)", "gNodeB (gNB)", ""Accesspoint","transmissionpoint","receptionpoint","transmission / reception point", "cell", "sector", "cell group", "cell group" Terms such as "carrier" and "component carrier" can be used interchangeably. Base stations are sometimes referred to by terms such as macrocells, small cells, femtocells, and picocells.

The base station can accommodate one or more (eg, three) cells. When a base station accommodates multiple cells, the entire coverage area of the base station can be divided into multiple smaller areas, each smaller area being a base station subsystem (eg, a small indoor base station (RRH:)). Communication services can also be provided by Remote Radio Head). The term "cell" or "sector" is used in this coverage as part or all of the coverage area of at least one of the base stations and base station subsystems that provide communication services. Point to.

<Mobile station>
In the present disclosure, terms such as "mobile station (MS)", "user terminal", "user equipment (UE)", and "terminal" may be used interchangeably. ..

Mobile stations can be used by those skilled in the art as subscriber stations, mobile units, subscriber units, wireless units, remote units, mobile devices, wireless devices, wireless communication devices, remote devices, mobile subscriber stations, access terminals, mobile terminals, wireless. It may also be referred to as a terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable term.

<Base station / Mobile station>
At least one of the base station and the mobile station may be referred to as a transmitting device, a receiving device, a communication device, or the like. At least one of the base station and the mobile station may be a device mounted on the mobile body, the mobile body itself, or the like. The moving body may be a vehicle (for example, a car, an airplane, etc.), an unmanned moving body (for example, a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned type). ) May be. It should be noted that at least one of the base station and the mobile station includes a device that does not necessarily move during communication operation. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

Further, the base station in the present disclosure may be read by the user terminal. For example, the communication between the base station and the user terminal is replaced with the communication between a plurality of user terminals (for example, it may be called D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.). Each aspect / embodiment of the present disclosure may be applied to the configuration. In this case, the user terminal may have the function of the above-mentioned base station. In addition, words such as "up" and "down" may be read as words corresponding to communication between terminals (for example, "side"). For example, an uplink channel, a downlink channel, and the like may be read as a side channel.

Similarly, the user terminal in the present disclosure may be read as a base station. In this case, the base station may have the functions of the user terminal described above.

<Meaning and interpretation of terms>
The terms "determining" and "determining" as used in this disclosure may include a wide variety of actions. "Judgment" and "decision" are, for example, judgment (judging), calculation (calculating), calculation (computing), processing (processing), derivation (deriving), investigation (investigating), search (looking up, search, inquiry). (For example, searching in a table, database or another data structure), ascertaining may be regarded as "judgment" or "decision". Also, "judgment" and "decision" are receiving (for example, receiving information), transmitting (for example, transmitting information), input (input), output (output), and access. (Accessing) (for example, accessing data in memory) may be regarded as "judgment" or "decision". In addition, "judgment" and "decision" mean that "resolving", "selecting", "choosing", "establishing", "comparing", etc. are regarded as "judgment" and "decision". Can include. That is, "judgment" and "decision" may include considering some action as "judgment" and "decision". Further, "judgment (decision)" may be read as "assuming", "expecting", "considering" and the like.

The terms "connected", "coupled", or any variation thereof, mean any direct or indirect connection or connection between two or more elements, and each other. It can include the presence of one or more intermediate elements between two "connected" or "combined" elements. The connection or connection between the elements may be physical, logical, or a combination thereof. For example, "connection" may be read as "access". As used in the present disclosure, the two elements use at least one of one or more wires, cables and printed electrical connections, and, as some non-limiting and non-comprehensive examples, the radio frequency domain. Can be considered to be "connected" or "coupled" to each other using electromagnetic energies having wavelengths in the microwave and light (both visible and invisible) regions.

<Reference signal>
The reference signal may also be abbreviated as RS (Reference Signal) and may be referred to as a pilot (Pilot) depending on the applied standard.

<Meaning of "based on">
The phrase "based on" as used in this disclosure does not mean "based on" unless otherwise stated. In other words, the statement "based on" means both "based only" and "at least based on".

<"First", "Second">
Any reference to elements using designations such as "first", "second" as used in the present disclosure does not generally limit the quantity or order of those elements. These designations can be used in the present disclosure as a convenient way to distinguish between two or more elements. Thus, references to the first and second elements do not mean that only two elements can be adopted, or that the first element must somehow precede the second element.

<"Means">
The "means" in the configuration of each of the above devices may be replaced with a "part", a "circuit", a "device" and the like.

<Open format>
When "include", "including" and variations thereof are used in the present disclosure, these terms are as comprehensive as the term "comprising". Is intended. Furthermore, the term "or" used in the present disclosure is intended not to be an exclusive OR.

<Time unit such as TTI, frequency unit such as RB, wireless frame configuration>
The radio frame may be composed of one or more frames in the time domain.
Each one or more frames in the time domain may be referred to as a subframe.

Subframes may further consist of one or more slots in the time domain. The subframe may have a fixed time length (eg, 1 ms) that is independent of numerology.

The numerology may be a communication parameter that applies to at least one of the transmission and reception of a signal or channel. Numerology includes, for example, SubCarrier Spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame configuration, transmission / reception. At least one of a specific filtering process performed by the machine in the frequency domain, a specific windowing process performed by the transceiver in the time domain, and the like may be indicated.

The slot may be composed of one or more symbols (OFDMA (Orthogonal Frequency Division Multiplexing) symbol, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbol, etc.) in the time domain. Slots may be unit of time based on numerology.

The slot may include a plurality of mini slots. Each minislot may consist of one or more symbols in the time domain. Further, the mini slot may be referred to as a sub slot. A minislot may consist of a smaller number of symbols than the slot. PDSCH (or PUSCH) transmitted in time units larger than the minislot may be referred to as PDSCH (or PUSCH) mapping type A. The PDSCH (or PUSCH) transmitted using the minislot may be referred to as the PDSCH (or PUSCH) mapping type B.

Radio frames, subframes, slots, minislots and symbols all represent time units when transmitting signals. The radio frame, subframe, slot, minislot and symbol may have different names corresponding to each.

For example, one subframe may be referred to as a transmission time interval (TTI), a plurality of consecutive subframes may be referred to as a TTI, and one slot or one minislot may be referred to as a TTI. You may. That is, at least one of the subframe and TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (eg, 1-13 symbols), or a period longer than 1 ms. It may be. The unit representing TTI may be called a slot, a mini slot, or the like instead of a subframe.

Here, TTI refers to, for example, the minimum time unit of scheduling in wireless communication. For example, in the LTE system, the base station schedules each user terminal to allocate radio resources (frequency bandwidth that can be used in each user terminal, transmission power, etc.) in TTI units. The definition of TTI is not limited to this.

The TTI may be a transmission time unit such as a channel-encoded data packet (transport block), a code block, or a code word, or may be a processing unit such as scheduling or link adaptation. When a TTI is given, the time interval (for example, the number of symbols) to which the transport block, code block, code word, etc. are actually mapped may be shorter than the TTI.

When one slot or one minislot is called TTI, one or more TTIs (that is, one or more slots or one or more minislots) may be the minimum time unit for scheduling. Further, the number of slots (number of mini-slots) constituting the minimum time unit of the scheduling may be controlled.

A TTI having a time length of 1 ms may be referred to as a normal TTI (TTI in LTE Rel. 8-12), a normal TTI, a long TTI, a normal subframe, a normal subframe, a long subframe, a slot, and the like. TTIs shorter than normal TTIs may be referred to as shortened TTIs, short TTIs, partial TTIs (partial or fractional TTIs), shortened subframes, short subframes, minislots, subslots, slots and the like.

The long TTI (for example, normal TTI, subframe, etc.) may be read as a TTI having a time length of more than 1 ms, and the short TTI (for example, shortened TTI, etc.) is less than the TTI length of the long TTI and 1 ms. It may be read as a TTI having the above TTI length.

A resource block (RB) is a resource allocation unit in the time domain and frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers contained in the RB may be the same regardless of the numerology, and may be, for example, 12. The number of subcarriers contained in the RB may be determined based on numerology.

The time domain of the RB may also include one or more symbols and may be one slot, one minislot, one subframe, or one TTI in length. Each 1TTI, 1 subframe, etc. may be composed of one or a plurality of resource blocks.

One or more RBs include a physical resource block (PRB: Physical RB), a sub-carrier group (SCG: Sub-Carrier Group), a resource element group (REG: Resource Element Group), a PRB pair, an RB pair, and the like. May be called.

Further, the resource block may be composed of one or a plurality of resource elements (RE: Resource Element). For example, 1RE may be a radio resource area of 1 subcarrier and 1 symbol.

Bandwidth Part (BWP) (which may also be called partial bandwidth, etc.) may represent a subset of consecutive common resource blocks (RBs) for a neurology in a carrier. good. Here, the common RB may be specified by the index of the RB with respect to the common reference point of the carrier. PRBs may be defined in a BWP and numbered within that BWP.

The BWP may include a BWP for UL (UL BWP) and a BWP for DL (DL BWP). One or more BWPs may be set in one carrier for the UE.

At least one of the configured BWPs may be active and the UE may not expect to send or receive a given signal / channel outside the active BWP. In addition, "cell", "carrier" and the like in this disclosure may be read as "BWP".

The structures such as wireless frames, subframes, slots, minislots and symbols described above are merely examples. For example, the number of subframes contained in a wireless frame, the number of slots per subframe or wireless frame, the number of minislots contained in a slot, the number of symbols and RBs contained in a slot or minislot, and the number of RBs. The number of subcarriers, the number of symbols in the TTI, the symbol length, the cyclic prefix (CP) length, and the like can be changed in various ways.

<Maximum transmission power>
The "maximum transmit power" described in the present disclosure may mean the maximum value of the transmit power, the nominal UE maximum transmit power, or the rated maximum transmit power (the nominal UE maximum transmit power). It may mean the rated UE maximum transmit power).

<Article>
In the present disclosure, if articles are added by translation, for example a, an and the in English, the disclosure may include the plural nouns following these articles.

<"Different">
In the present disclosure, the term "A and B are different" may mean "A and B are different from each other". The term may mean that "A and B are different from C". Terms such as "separate" and "combined" may be interpreted in the same way as "different".

One aspect of the present disclosure is useful for wireless communication systems.

1 Metal reflector 2 Metasurface reflector 11 Base station 12, 12a-12c Radio reflector 13 Terminal 21 Dielectric substrate 22 Metasurface substrate 22a Unit cell 31 Connecting member 32 Adjusting unit 41 Connecting member 42 Adjusting unit 1001 Processor 1002 Memory 1003 Storage 1004 Communication equipment 1005 Input unit 1006 Output unit 1007 Bus A1 area G1 Gap

Claims (6)

Meta surface board and
A dielectric substrate arranged to face the metasurface substrate and
An adjusting unit that adjusts the distance between the meta-surface substrate and the dielectric substrate,
Radio wave reflector with. It also has an operating device that accepts operations,
The adjusting unit adjusts the distance according to the movement of the operating device.
The radio wave reflecting device according to claim 1. It also has an input device, which accepts the set time and set distance,
The adjusting unit adjusts the distance according to the set distance set for each set time.
The radio wave reflecting device according to claim 1 or 2. The metasurface substrate changes the resonance frequency of the radio wave transmittance based on the distance.
The radio wave reflecting device according to any one of claims 1 to 3. The meta-surface substrate and the dielectric substrate take a parallel or non-parallel state based on the adjustment of the distance.
The radio wave reflecting device according to any one of claims 1 to 4. The dielectric constant of the dielectric substrate is larger than the dielectric constant of the metasurface substrate.
The radio wave reflecting device according to any one of claims 1 to 5.

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