Antenna Device

Abstract

This antenna device comprises: an array antenna having a plurality of antenna elements arranged in a certain direction; and a reflective mirror provided at a position spaced a predetermined distance in the direction from one of the antenna elements positioned on both ends among the plurality of antenna elements.

Description

[Technical field]

[0001] The present disclosure relates to an antenna device. [Background technology]

[0002] In the 5th Generation (5G) mobile communication system, the radiated power share in global directions has been newly added as an evaluation index of antenna and wireless communication performance, and the standard value is being considered by the 3GPP (3rd Generation Partnership Project). With the introduction of this evaluation index, it is important to improve the characteristics of the spherical coverage, which is the area ratio where the radiated power reaches a specified characteristic when the antenna beam is scanned.

[0003] Patent Document 1 discloses a configuration for improving spherical coverage by arranging multiple types of antenna elements around a mobile terminal.

[0004] Patent Document 2 discloses an example of a configuration in which a reflector is provided for an array antenna fed with a phase difference, and the antenna directivity is radiated in a horizontal direction relative to the antenna substrate. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Utility Model Registration No. 3212787 [Patent Document 2] Japanese Patent Application Publication No. 2-179103 Summary of the Invention [Problem to be solved by the invention]

[0006] The configuration of Patent Document 1 requires multiple types of antenna element arrangements and a complex power supply configuration, leaving room for consideration in terms of cost and mounting area.The configuration of Patent Document 2 is not effective in improving spherical coverage because the antenna radiation direction is limited to the direction of the aperture surface of the reflector.

[0007] A non-limiting example of the present disclosure contributes to providing a technology that can expand the directivity control range of an array antenna with a simple configuration and improve the spherical coverage characteristics. [Means for solving the problem]

[0008] The antenna device of the present disclosure comprises an array antenna having a plurality of antenna elements arranged along a certain direction, and a reflector provided at a position a predetermined distance along the direction from one of the antenna elements located at both ends among the plurality of antenna elements.

[0009] In addition, these comprehensive or specific aspects may be realized by a system, an apparatus, a method, an integrated circuit, a computer program, or a recording medium, or may be realized by any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium. Effect of the Invention

[0010] According to the present disclosure, the directivity control range of an array antenna can be expanded with a simple configuration, thereby improving spherical coverage characteristics.

[0011] Further advantages and benefits of an embodiment of the present disclosure will become apparent from the specification and drawings, in which such advantages and / or benefits are provided by some of the embodiments and features described in the specification and drawings, respectively, but not necessarily all of which are provided to obtain one or more identical features. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view showing an example of a configuration of an antenna device according to a first embodiment of the present disclosure. [Diagram 2] FIG. 1 is a perspective view showing an example of an operation of the antenna device according to the first embodiment of the present disclosure. [Diagram 3] FIG. 1 is a diagram showing an example of an arrangement of reflecting mirrors according to the first embodiment of the present disclosure; [Figure 4] FIG. 1 is a diagram showing an example of a radiation pattern of an antenna device according to a first embodiment of the present disclosure when the feed phase difference is 0 degrees; [Diagram 5] FIG. 1 is a diagram showing an example of a radiation pattern of an antenna device according to a first embodiment of the present disclosure when the feed phase difference is 150 degrees; [Figure 6] FIG. 11 is a perspective view showing an example of a configuration of an antenna device according to a second embodiment of the present disclosure. [Figure 7] FIG. 13 is a perspective view showing an example of a configuration of an antenna device according to a third embodiment of the present disclosure. [Figure 8] FIG. 13 is a perspective view showing an example of a configuration of an antenna device according to a fourth embodiment of the present disclosure. [Figure 9] FIG. 13 is a perspective view showing an example of a configuration of an antenna device according to a fifth embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed explanation than necessary may be omitted. For example, detailed explanation of already well-known matters or duplicate explanation of substantially the same configuration may be omitted. This is to avoid the following explanation becoming unnecessarily redundant and to facilitate understanding by those skilled in the art.

[0014] It should be noted that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0015] (Embodiment 1) The first embodiment will be described with reference to FIGS. 1 to 5. FIG.

[0016] [1-1. Configuration] 1 is a perspective view showing an example of a configuration of an antenna device 100 according to a first embodiment of the present disclosure. The antenna device 100 includes a plurality of array antenna elements 102-k (e.g., k=1, 2, 3, or 4; hereinafter, also collectively referred to as array antennas 102) formed on a surface of a single-layer or multi-layer dielectric substrate 101, a phase shifter (not shown) connected to each of the plurality of array antenna elements 102-k, and a reflector 104 arranged vertically or approximately vertically on the dielectric substrate 101. A GND plane (not shown) is formed on the rear surface of the dielectric substrate 101.

[0017] Each of the array antenna elements 102-k may be, for example, a planar antenna element called a patch antenna element or a microstrip antenna element. In the example of Fig. 1, four square patch antenna elements 102-k are illustrated, but the number of array antenna elements is not limited to four and may be two or more.

[0018] [1-2. Operation and Effects] FIG. 2 is a perspective view showing an example of the operation of the antenna device according to the first embodiment of the present disclosure. An example of the operation of the antenna device 100 configured as described above will be described below with reference to FIG. 2. Three radiation directions of the array antenna controlled by the feed phase difference generated by a phase shifter (not shown) are represented by radiation direction α (solid line) 105, radiation direction γ (dashed line) 106, and radiation direction β (dotted line) 107. The radiation direction α 105 is the radiation direction when the feed phase difference is 150 degrees, the radiation direction γ 106 is the radiation direction when the feed phase difference is 0 degrees, and the radiation direction β 107 is the radiation direction when the feed phase difference is 90 degrees. As will be described later with reference to FIG. 4 and FIG. 5, the radiation direction γ 106 corresponds to the maximum feed phase difference effective for the beam tilt (inclination) of the array antenna 102.

[0019] Radiation direction γ106 is, for example, a direction perpendicular or approximately perpendicular to the surface of dielectric substrate (hereinafter also simply referred to as "substrate") 101 (in other words, a direction along the positive direction of the Z axis). The starting point of radiation direction γ106 is, for example, a position on substrate 101 between array antenna element 102-2 and array antenna element 102-3, for example, a position corresponding to the center of the length (X-axis direction) of array antenna 102. The Y-axis corresponds to the width direction of dielectric substrate 101 (or array antenna 102).

[0020] When the feed phase difference between the multiple array antenna elements 102-k is 150 degrees, the main radiation direction of the array antenna 102 is diagonally upward with respect to the surface of the substrate 101 (in other words, a direction shifted toward the positive side of the X-axis with respect to the radiation direction γ106) in accordance with the feed phase difference, as shown in FIG. 2.

[0021] As the feed phase difference is made smaller than 90 degrees, the main radiation direction of array antenna 102 approaches the direction along the surface of substrate 101 (the positive direction of the X-axis). For example, when the feed phase difference is 150 degrees, the main radiation direction of array antenna 102 becomes the direction toward the curved surface of reflector 104, as shown in Fig. 2. Radio waves incident on reflector 104 are reflected by the curved surface of reflector 104 in, for example, the direction indicated by solid arrow 108 (in other words, the direction along the surface of substrate 101 (the negative direction of the X-axis)).

[0022] In this way, by changing (controlling) the feed phase difference between array antenna elements 102-k and controlling the main irradiation direction of the radio waves to the direction of incidence on reflector 104, the directivity control range of array antenna 102 can be expanded compared to the case where reflector 104 is not provided.

[0023] 3 is a diagram showing an example of an arrangement of reflectors according to the first embodiment of the present disclosure. FIG. 3 shows the relationship between the antenna device 100 and the reflector 104 according to the present disclosure. In FIG. 3, θ arepresents the aperture angle (deg) of reflector 104, and the height (Z direction) of reflector 104 is D / 2 (mm). Here, D represents the aperture diameter of reflector 104. f is the focal length (mm) of reflector 104. C represents the center position of array antenna 102 in the longitudinal direction, and is, for example, on the center line of the opposing sides of array antenna elements 102-2 and 102-3. Therefore, in this example, focal length f is the distance from center C of array antenna 102 in the longitudinal direction to the position of reflector 104 on dielectric substrate 101.

[0024] In antenna device 100 having reflector 104 shown in FIG. 3, by controlling the feed phase to antenna device 100 with a phase shifter (not shown), the maximum radiation direction can be expanded to the direction along the surface of substrate 101 (the negative direction of the X-axis) by expanding the directivity control range of array antenna 102, as will be described later with reference to FIGS. 4 and 5, and as a result, the spherical coverage of the antenna device can be improved.

[0025] In other words, the height D / 2 (mm) of the reflector 104 is the maximum θ that the antenna device 100 can control by the feed phase of the phase shifter. a This allows the antenna to be designed to correspond to the maximum radiation direction of approximately -50 degrees as shown in FIG. 5(a) when a phase difference larger than the feed phase difference of 90 degrees is added (for example, θ a When the angle is between -50 degrees and -90 degrees), the radio waves are reflected by reflector 104 and radiated in the opposite horizontal direction (+90 degree side), so that the maximum radiation direction in Figure 5(a) can be brought even closer to -90 degrees, improving the spherical coverage.

[0026] The shape of the reflecting surface of reflector 104 is, for example, a parabolic shape, but may be another curved shape. In other words, the shape of the reflecting surface may be any shape that can convert the direction of radio waves incident obliquely to a horizontal plane (incident direction) into a direction along the horizontal plane (outgoing direction) by reflection.

[0027] Reflector 104 may be placed at a predetermined distance near one of both ends in the longitudinal direction of array antenna 102 on dielectric substrate 101. The height D / 2 of reflector 104 can be made smaller as reflector 104 approaches array antenna 102, so it is preferable to place reflector 104 as close to array antenna 102 as possible. On the other hand, a condition is that reflector 104 does not cover center C of array antenna 102 when viewed from the Z direction, in other words, the aperture angle of reflector 104 is less than 90 degrees.

[0028] Fig. 4 is a diagram showing an example of a radiation pattern when the feed phase difference of the antenna device according to the first embodiment of the present disclosure is 0 degrees. In comparison with Fig. 3, in Fig. 4(a) and (b), -90 degrees is the positive direction of the X-axis, +90 degrees is the negative direction of the X-axis, 0 degrees is the positive direction of the Z-axis, and 180 degrees is the negative direction of the Z-axis.

[0029] Fig. 4(a) shows an example of a radiation pattern of a conventional antenna device having no reflector when the feed phase difference is 0 degrees, and Fig. 4(b) shows an example of a radiation pattern of an antenna device 100 having a reflector 104 according to the first embodiment of the present disclosure when the feed phase difference is 0 degrees. In the conventional antenna device having no reflector shown in Fig. 4(a), when the feed phase difference is 0 degrees, the 0 degree direction is the maximum radiation direction 410. On the other hand, in the antenna device 100 having a reflector 104 shown in Fig. 4(b), when the feed phase difference is 0 degrees, the 0 degree direction is the maximum radiation direction 420, which is the same as the antenna device having no reflector 104.

[0030] Fig. 5 is a diagram showing an example of a radiation pattern when the feed phase difference of the antenna device according to the first embodiment of the present disclosure is 150 degrees. In comparison with Fig. 3, in Fig. 5(a) and (b), -90 degrees is the positive direction of the X-axis, +90 degrees is the negative direction of the X-axis, 0 degrees is the positive direction of the Z-axis, and 180 degrees is the negative direction of the Z-axis.

[0031] Fig. 5(a) shows an example of a radiation pattern of a conventional antenna device without a reflector when the feed phase difference is 150 degrees, and Fig. 5(b) shows an example of a radiation pattern of an antenna device 100 according to an embodiment of the present disclosure having a reflector 104 when the feed phase difference is 150 degrees. In the conventional antenna device without a reflector shown in Fig. 5(a), when the feed phase difference is 150 degrees, the maximum radiation direction 510 is approximately -50 degrees. On the other hand, in the antenna device 100 with a reflector 104 shown in Fig. 5(b), when the feed phase difference is 150 degrees, the maximum radiation direction 520 is +90 degrees, which is significantly different from the maximum radiation direction of approximately -50 degrees when the reflector 104 is not present.

[0032] It can be seen that the radiation pattern of the antenna device 100 having the reflector 104 when the feed phase difference is 150 degrees as shown in Fig. 5(b) is closer to a circle than the radiation pattern of the antenna device having no reflector 104 as shown in Fig. 5(a) when the feed phase difference is 150 degrees. Also, it can be seen that the radiation pattern of the antenna device 100 having the reflector 104 when the feed phase difference is 0 degrees as shown in Fig. 4(b) is closer to a circle than the radiation pattern of the antenna device having no reflector 104 as shown in Fig. 4(a) when the feed phase difference is 0 degrees.

[0033] Therefore, in the case of the antenna device 100 according to the present disclosure having a reflector 104, when the feed phase difference is 0 degrees and 150 degrees, the radiation pattern approaches a circle, and the spherical coverage of the antenna device 100 is improved, compared to an antenna device without a reflector 104.

[0034] (Embodiments 2 and 3) Second and third embodiments of the present disclosure will be described with reference to Fig. 6 and Fig. 7. Fig. 6 is a perspective view showing an example of the configuration of an antenna device according to a second embodiment of the present disclosure, and Fig. 7 is a perspective view showing an example of the configuration of an antenna device according to a third embodiment of the present disclosure.

[0035] Antenna device 200 has a configuration in which reflector 104 in antenna device 100 is shared with part of cellular antenna 205. Antenna device 200 in FIG. 6 differs from antenna device 300 in FIG. 7 in the shape of cellular antenna 205 and cellular antenna 305. Cellular antenna 205 shown in FIG. 6 has a three-dimensional L-shaped shape when viewed from the Y direction, and is configured such that one side of cellular antenna 205 supports reflector 104 and the other side of cellular antenna 205 is installed on dielectric substrate 101. On the other hand, cellular antenna 305 shown in FIG. 7 includes two cellular antenna components 305-1 and 305-2, and is configured planarly on dielectric substrate 101, integral with or in contact with reflector 104.

[0036] By configuring the cellular antenna 205 or 305 in this way, the reflector 104 and the cellular antenna are integrated or in contact with each other, so there is no need to provide a dedicated part for supporting the reflector 104. Therefore, it is possible to configure the antenna devices 200 and 300 that are low-cost or small-sized and have improved spherical coverage characteristics.

[0037] Such a cellular antenna may be an antenna for applications other than LTE, such as a wireless LAN (Local Area Network), a GPS (Global Positioning System), or Bluetooth (registered trademark).

[0038] (Embodiment 4) The fourth embodiment will be described with reference to FIG. 8. FIG. 8 is a perspective view showing a configuration of an antenna device 400 according to the fourth embodiment of the present disclosure. The part 405 of the housing is, for example, a part of the housing of a mobile wireless terminal. The antenna device 400 is configured to share the reflector 104 in the antenna device 100 with the part 405 of the housing of the mobile wireless terminal. In the example shown in FIG. 8, the reflector 104 is installed on the surface of the part 405 of the housing. The reflector 104 may be molded integrally with the part 405 of the housing, or may be molded as a separate part, and then the reflector 104 may be disposed on the part 405 of the housing. With this configuration, the part 405 of the housing is shared as a support part for the reflector 104, so there is no need to provide a dedicated support part for the reflector 104, and it is possible to configure an antenna device 400 that is low-cost or small-sized and has improved spherical coverage characteristics.

[0039] It should be noted that a cellular antenna may be provided on any surface of part 405 of the housing, and the cellular antenna may be integrated with reflector 104 as described with reference to FIGS.

[0040] (Embodiment 5) Fig. 9 is a perspective view showing an example of the configuration of an antenna device according to embodiment 5 of the present disclosure. Antenna device 500 shown in Fig. 9 includes dielectric substrate 101, array antenna 102, and reflector 104, which have already been described, and further includes cellular antennas 505-1 and 505-2 that can be used in wireless communications such as LTE (long term evolution) or 5G.

[0041] Each of cellular antennas 505-1 and 505-2 is formed, for example, by a monopole antenna or an inverted F antenna, and may have a length approximately equal to one-quarter (λ / 4) of the wavelength λ corresponding to the frequency to be received.

[0042] In this example, cellular antennas 505-1 and 505-2 are arranged on both sides of array antenna 102 and reflector 104 on dielectric substrate 101. However, one cellular antenna may be arranged on one side in the longitudinal direction of dielectric substrate 101. Also, as described with reference to Figures 6 and 7, reflector 104 may be molded integrally with cellular antenna 505-1 or 505-2.

[0043] By adopting the antenna configuration shown in Figure 9, for example, a 5G antenna and a 5G antenna for the 6 GHz band or less or a cellular antenna for 4G or earlier can be compactly configured on the same dielectric substrate 101, and further, since the 5G antenna has a reflector 104, it is possible to improve the spherical coverage characteristics while being compact and low cost.

[0044] (Other embodiments) As described above, the first to fifth embodiments have been described as examples of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to these, and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made. In addition, it is also possible to combine the components described in the first to fifth embodiments to create new embodiments.

[0045] The present disclosure can be realized in software, hardware, or software in conjunction with hardware.

[0046] Each functional block used in the description of the above embodiments may be partially or entirely realized as an LSI, which is an integrated circuit, and each process described in the above embodiments may be partially or entirely controlled by one LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of one chip that includes some or all of the functional blocks. The LSI may have data input and output. Depending on the degree of integration, the LSI may be called an IC, a system LSI, a super LSI, or an ultra LSI.

[0047] The method of integration is not limited to LSI, and may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. Also, after LSI manufacturing, a programmable FPGA (Field Programmable Gate Array) or a reconfigurable processor that can reconfigure the connections and settings of circuit cells inside the LSI may be used. The present disclosure may be realized as digital processing or analog processing.

[0048] Furthermore, if a new integrated circuit technology that can replace LSI appears due to the progress of semiconductor technology or a derivative technology, it is possible to integrate the functional blocks using that technology. The application of biotechnology is also a possibility.

[0049] The present disclosure may be implemented in any type of apparatus, device, or system with communications capabilities (collectively, communications apparatus), including, but not limited to, telephones (e.g., cell phones, smartphones, etc.), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks, etc.), cameras (e.g., digital still / video cameras), digital players (e.g., digital audio / video players), wearable devices (e.g., wearable cameras, smart watches, tracking devices, etc.), game consoles, digital book readers, telehealth / telemedicine devices, communications-enabled vehicles or mobile conveyances (e.g., cars, planes, ships, etc.), and combinations of the above-mentioned devices.

[0050] Communications Equipment includes, but is not limited to portable or mobile equipment, non-portable or fixed equipment, devices and systems of any kind, such as smart home devices (appliances, lighting equipment, smart meters or metering devices, control panels, etc.), vending machines and any other "Things" that may exist on an Internet of Things (IoT) network.

[0051] Communications include data communications via cellular systems, wireless LAN systems, communications satellite systems, etc., as well as data communications via combinations of these.

[0052] A communications apparatus also includes devices, such as controllers and sensors, connected or coupled to a communications device that performs the communications functions described in this disclosure, such as controllers and sensors that generate control and data signals used by the communications device to perform the communications functions of the communications apparatus.

[0053] The communication apparatus also includes infrastructure facilities, such as base stations, access points, and any other apparatus, device, or system that communicates with or controls the various apparatuses listed above, but are not limited to these.

[0054] <Summary of this disclosure> The antenna device of the present disclosure comprises an array antenna having a plurality of antenna elements arranged along a certain direction, and a reflector provided at a position a predetermined distance along the direction from one of the antenna elements located at both ends among the plurality of antenna elements.

[0055] The position of the reflector of the antenna device disclosed herein is a position where radio waves are incident within a part of the angular range of the main radiation direction of radio waves from the array antenna which changes according to the feed phase difference between the antenna elements, and the reflecting surface of the reflector has a curved shape that converts the reflection direction when the main radiation direction is oblique to a horizontal plane into a direction along the horizontal plane.

[0056] The reflector aperture angle of the antenna device of the present disclosure is less than 90 degrees.

[0057] The reflector of the antenna device of the present disclosure is configured using another antenna different from the array antenna or a part of the another antenna.

[0058] The reflector of the antenna device of the present disclosure is supported by components that constitute the antenna device.

[0059] The antenna element of the antenna device of the present disclosure is a planar antenna.

[0060] The disclosures of the specification, drawings and abstract contained in Japanese Patent Application No. 2019-191812, filed on October 21, 2019, are incorporated herein by reference in their entirety. [Industrial Applicability]

[0061] The present disclosure is applicable, for example, to devices or terminals that perform wireless communication. [Explanation of symbols]

[0062] 100,200,300,400,500 Antenna equipment 101 Dielectric substrate 102 Array Antenna 102-1~102-4 Array antenna elements 104 Reflector 205 Cellular Antenna 305-1, 305-2 Cellular Antenna 405 Part of the housing 505-1, 505-2 Cellular Antenna

Claims

1. An array antenna having a plurality of antenna elements arranged along a certain direction on a dielectric substrate; a reflector provided on the dielectric substrate at a position a predetermined distance away from one of the antenna elements located at both ends of the plurality of antenna elements along the direction, the position of the reflector is a position at which radio waves are incident within a part of an angular range of a main radiation direction of radio waves from the array antenna, the angular range changing according to a feed phase difference between the antenna elements; a reflecting surface of the reflector having a curved shape that converts a reflection direction in a case where the main radiation direction is oblique to a surface of the dielectric substrate into a direction along the surface of the dielectric substrate; Antenna device.

2. The aperture angle of the reflector is less than 90 degrees.

2. The antenna device according to claim 1.

3. The reflector is supported by components constituting the antenna device.

2. The antenna device according to claim 1.

4. The antenna device according to claim 1 , wherein the antenna element is a planar antenna.

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