Sub-array antenna device

Abstract

This sub-array antenna device comprises: an antenna array which is configured from a plurality of sub-arrays having a plurality of radiation elements; an IC which supplies RF signals to the plurality of sub-arrays; and a substrate to which the plurality of sub-arrays and the IC are provided. In the sub-array antenna device, the peak direction of electromagnetic waves radiated from the antenna array can be inclined to a direction orthogonal to the substrate.

Description

Subarray antenna device

[0001] The present invention relates to a subarray antenna device. This application claims priority to Japanese Patent Application No. 2023-111795, filed on July 6, 2023, the contents of which are incorporated herein by reference.

[0002] In the field of high-speed wireless communications, antenna devices capable of beamforming are used. For example, Patent Document 1 discloses an array antenna device that forms a directional beam with controllable directionality. The array antenna device is installed on, for example, a ceiling or a wall.

[0003] Japanese Patent Application Publication No. 2023-39310

[0004] In the array antenna device, it may be difficult to set the radiation direction of a beam with a large inclination.

[0005] An object of one aspect of the present invention is to provide a subarray antenna device capable of setting the radiation direction of a beam with a large inclination.

[0006] A subarray antenna device according to a first aspect of the present invention comprises an antenna array consisting of a plurality of subarrays each having a plurality of radiating elements, an IC that supplies RF signals to the plurality of subarrays, and a substrate on which the plurality of subarrays and the IC are mounted, and is capable of tilting the peak direction of the electromagnetic waves radiated from the antenna array relative to a direction perpendicular to the substrate.

[0007] According to the first aspect of the present invention, the peak direction of the electromagnetic waves radiated from the antenna array is inclined with respect to the direction perpendicular to the substrate. Therefore, even when the subarray antenna device is installed parallel to the installation surface, it can radiate a beam inclined at a sufficient angle. Therefore, the inclination angle of the beam radiation direction can be set arbitrarily within a wide range depending on the usage environment, usage form, etc. of the subarray antenna device.

[0008] In a second aspect of the present invention, in the subarray antenna device of the first aspect, the phases of the RF signals supplied from the IC to two or more of the plurality of radiating elements constituting the subarray may be different.

[0009] A third aspect of the present invention is the subarray antenna device of the second aspect, wherein the plurality of radiating elements constituting the plurality of subarrays are electrically connected to the IC via a first signal line and a second signal line, and the length of the first signal line and the length of the second signal line may be different.

[0010] In a fourth aspect of the present invention, in the subarray antenna device of any one of the first to third aspects, the plurality of subarrays may include a first subarray and a second subarray different from the first subarray. The first subarray may have RF signals supplied from the IC to two or more of the plurality of radiating elements with different phases. The second subarray may have RF signals supplied from the IC to two or more of the plurality of radiating elements with the same phase.

[0011] A fifth aspect of the present invention is the subarray antenna device of the fourth aspect, wherein the plurality of subarrays are arranged in a rectangular lattice pattern, and the second subarray is a plurality of subarrays arranged along diagonals of the rectangular lattice-shaped antenna array.

[0012] One aspect of the present invention provides a subarray antenna device capable of setting the radiation direction of a beam with a large inclination.

[0013] FIG. 1 is a plan view of a subarray antenna device according to a first embodiment. FIG. 2 is a schematic view showing a first example of a subarray of the subarray antenna device according to the first embodiment. FIG. 3 is a schematic view showing a second example of a subarray of the subarray antenna device according to the first embodiment. FIG. 4 is a schematic view showing a first installation example of the subarray antenna device according to the first embodiment. FIG. 5 is a schematic view showing a second installation example of the subarray antenna device according to the first embodiment. FIG. 6 is a diagram showing a radiation pattern of a subarray antenna device of a comparative example. FIG. 7 is a diagram showing a radiation pattern of a subarray antenna device of an example. FIG. 8 is a plan view of a subarray antenna device according to a second embodiment. FIG. 9 is a schematic view showing a subarray of the subarray antenna device according to the second embodiment. FIG. 10 is a schematic view showing an installation example of the subarray antenna device according to the second embodiment. FIG. 11 is a plan view of a subarray antenna device according to a third embodiment. FIG. 12 is a schematic view showing a first subarray of the subarray antenna device according to the third embodiment. FIG. 13 is a schematic view showing a second subarray of the subarray antenna device according to the third embodiment. FIG. 14 is a schematic view showing an installation example of the subarray antenna device according to the third embodiment.

[0014] Hereinafter, a subarray antenna device according to an embodiment of the present invention will be described with reference to the drawings.

[0015] [Subarray Antenna Apparatus] (First Embodiment) Fig. 1 is a configuration diagram of a subarray antenna apparatus 100 according to a first embodiment. Hereinafter, the "subarray antenna apparatus" may be simply referred to as the "antenna apparatus".

[0016] As shown in Fig. 1, the antenna device 100 includes a plurality of subarrays 10, a plurality of ICs 20, and a substrate 30. In the following description, the X and Y directions are parallel to the first main surface 30a of the substrate 30. The X and Y directions are perpendicular to each other. The Z direction is perpendicular to the X and Y directions. A planar view is a view in the Z direction. The Y direction is an example of a first direction. The X direction is an example of a second direction.

[0017] +X is one direction along the X direction, which is to the right in FIG. 1. -X is the opposite direction to +X. +Y is one direction along the Y direction, which is upward in FIG. 1. -Y is the opposite direction to +Y. +Z is one direction along the Z direction, which is the direction toward the front of the page in FIG. 1. -Z is the opposite direction to +Z.

[0018] The subarrays 10 are patterned on the first main surface 30a of the substrate 30 based on a predetermined arrangement pattern. In this way, the subarrays 10 are provided on the substrate 30. The subarrays 10 are formed of a conductive material such as metal (copper, etc.). The subarrays 10 are formed by, for example, an additive method, a subtractive method, or the like.

[0019] The plurality of subarrays 10 are arranged in a rectangular lattice (matrix) in the X and Y directions to form an antenna array 11. The plurality of subarrays 10 arranged in the Y direction are spaced apart in the Y direction. The plurality of subarrays 10 arranged in the X direction are spaced apart in the X direction.

[0020] In the example shown in FIG. 1 , the antenna array 11 is composed of a total of 32 subarrays 10, four arranged in the Y direction and eight arranged in the X direction. That is, the antenna array 11 is composed of subarrays 10 arranged in a rectangular lattice shape (matrix shape) of four rows and eight columns. The four subarrays 10 arranged in the Y direction form a subarray column 10Y. The antenna array 11 has eight subarray columns 10Y. The eight subarrays 10 arranged in the X direction form a subarray row 10X. The antenna array 11 has four subarray rows 10X.

[0021] The plurality of subarrays 10 include a first subarray group 10A, a second subarray group 10B, a third subarray group 10C, and a fourth subarray group 10D.

[0022] The first subarray group 10A includes a plurality of subarrays 10 located on the +Y side and the −X side of the center. That is, the first subarray group 10A is configured from eight subarrays 10 included in the two subarray rows 10X from the top and the four subarray columns 10Y from the left in FIG. 1 .

[0023] The second subarray group 10B includes a plurality of subarrays 10 located on the +Y side and the +X side of the center. That is, the second subarray group 10B is configured from eight subarrays 10 included in the two subarray rows 10X from the top and the four subarray columns 10Y from the right in FIG. 1 .

[0024] The third subarray group 10C includes a plurality of subarrays 10 located on the −Y side and the −X side of the center. That is, the third subarray group 10C is configured from eight subarrays 10 included in the two subarray rows 10X from the bottom and the four subarray columns 10Y from the left in FIG. 1 .

[0025] The fourth subarray group 10D includes a plurality of subarrays 10 located on the −Y side and the +X side of the center. That is, the fourth subarray group 10D is configured from eight subarrays 10 included in the two subarray rows 10X from the bottom and the four subarray columns 10Y from the right in FIG. 1 .

[0026] The IC 20 is an integrated circuit that processes RF (Radio Frequency) signals. The IC 20 is mounted on, for example, the surface opposite to the first main surface 30a of the substrate 30. In this way, the IC 20 is provided on the substrate 30. The IC 20 supplies an RF signal to the radiating element 12 via the signal line 13 (see FIG. 2 ). The IC 20 is, for example, a BFIC (Beam Forming IC).

[0027] In the example shown in FIG. 1 , the antenna device 100 includes four ICs 20. The four ICs 20 are arranged in a rectangular grid (matrix) with two ICs in the Y direction and two in the X direction. The four ICs 20 are designated first to fourth ICs 20A to 20D. The first IC 20A is electrically connected to each of the subarrays 10 included in the first subarray group 10A. The second IC 20B is electrically connected to each of the subarrays 10 included in the second subarray group 10B. The third IC 20C is electrically connected to each of the subarrays 10 included in the third subarray group 10C. The fourth IC 20D is electrically connected to each of the subarrays 10 included in the fourth subarray group 10D.

[0028] Fig. 2 is a schematic diagram showing a first example of the subarray 10. As shown in Fig. 2, in this example, the subarray 10 includes two radiating elements 12 arranged in the Y direction and a signal line 13.

[0029] The radiating element 12 is formed in a rectangular shape. The radiating element 12 has a pair of sides along the X direction and a pair of sides along the Y direction. The two radiating elements 12 that make up the subarray 10 are formed adjacent to each other with a gap in the Y direction. One of the two radiating elements 12 is a first radiating element 12A. The other of the two radiating elements 12 is a second radiating element 12B. The second radiating element 12B is located on the +Y side of the first radiating element 12A.

[0030] The signal line 13 includes a baseline 14, a first branch line (first signal line) 15, and a second branch line (second signal line) 16. A base end 14a (first end) of the baseline 14 is electrically connected to the IC 20. The first branch line 15 and the second branch line 16 are branch lines branching off from a tip 14b (a second end opposite the first end) of the baseline 14. The tip 14b of the baseline 14 is not located at the midpoint between the first radiating element 12A and the second radiating element 12B in the Y direction. In the example shown in FIG. 2 , the tip 14b of the baseline 14 is located on the −Y side of the midpoint between the first radiating element 12A and the second radiating element 12B.

[0031] The first branch line 15 extends from the tip 14b of the base line 14 and reaches the first radiating element 12A. The first radiating element 12A is electrically connected to the IC 20 by the base line 14 and the first branch line 15. The first branch line 15 is L-shaped and has a first line 15A extending along the Y direction and a second line 15B extending along the X direction. The first line 15A extends linearly from the tip 14b of the base line 14 to the -Y side. The second line 15B extends linearly from the -Y side tip of the first line 15A to the -X side. L1 is the length of the first branch line 15.

[0032] The second branch line 16 extends from the tip 14b of the base line 14 and reaches the second radiating element 12B. The second radiating element 12B is electrically connected to the IC 20 by the base line 14 and the second branch line 16. The second branch line 16 is L-shaped and has a first line 16A extending along the Y direction and a second line 16B extending along the X direction. The first line 16A extends linearly from the tip 14b of the base line 14 to the +Y side. The second line 16B extends linearly from the tip of the +Y side of the first line 16A to the -X side. L2 is the length of the second branch line 16.

[0033] The second branch line 16 is longer than the first branch line 15. That is, length L2 > length L1. Therefore, the signal line from the IC 20 to the second radiating element 12B is longer than the signal line from the IC 20 to the first radiating element 12A. As a result, the phase of the RF signal supplied from the IC 20 to the first radiating element 12A is different from the phase of the RF signal supplied from the IC 20 to the second radiating element 12B. In other words, the phases of the RF signals supplied from the IC 20 to the two radiating elements 12 are different from each other.

[0034] The difference in length (L2-L1) between the first branch line 15 and the second branch line 16 can be determined, for example, so as to generate a phase difference equivalent to 1 / 8 to 1 / 2 (e.g., 1 / 4 to 1 / 2) of the designed wavelength of the RF signal. The difference in phase between the RF signal supplied from the IC 20 to the first radiating element 12A and the RF signal supplied from the IC 20 to the second radiating element 12B is, for example, 45 to 180 degrees (preferably 60 to 180 degrees). In other words, the difference in phase between the RF signals supplied from the IC 20 to the two radiating elements 12 (12A, 12B) is, for example, 45 to 180 degrees (preferably 60 to 180 degrees).

[0035] The radiating elements 12 (12A, 12B) receive an RF signal supplied from the signal line 13 and radiate an electromagnetic wave.

[0036] Fig. 3 is a schematic diagram showing a second example of the subarray 10. As shown in Fig. 3, in this example, the subarray 10 includes two radiating elements 12 arranged in the Y direction and a signal line 23. Components common to the first example (see Fig. 2) are assigned the same reference numerals and will not be described again.

[0037] The signal line 23 includes the base line 14, a first branch line 25 (first signal line), and a second branch line (second signal line) 26. The first branch line 25 and the second branch line 26 are branch lines branching off from a tip 14b (a second end opposite the first end) of the base line 14. The tip 14b of the base line 14 is located at the midpoint between the first radiating element 12A and the second radiating element 12B in the Y direction.

[0038] The first branch line 25 extends from the tip 14b of the base line 14 and reaches the first radiating element 12A. The first radiating element 12A is electrically connected to the IC 20 by the base line 14 and the first branch line 25. The first branch line 25 is L-shaped and has a first line 25A extending along the Y direction and a second line 25B extending along the X direction. The first line 25A extends linearly from the tip 14b of the base line 14 to the -Y side. The second line 25B extends linearly from the -Y side tip of the first line 25A to the -X side. L3 is the length of the first branch line 25.

[0039] The second branch line 26 extends from the tip 14b of the base line 14 to the second radiating element 12B. The second radiating element 12B is electrically connected to the IC 20 via the base line 14 and the second branch line 26. The second branch line 26 has a first line 26A, a second line 26B, a third line 26C, and a fourth line 26D. The first line 26A extends linearly from the tip 14b of the base line 14 to the +Y side. The second line 26B extends linearly from the tip on the +Y side of the first line 26A to the +X side. The third line 26C extends linearly from the tip on the +X side of the second line 26B to the +Y side. The fourth line 26D extends linearly from the tip on the +Y side of the third line 26C to the -X side. L4 is the length of the second branch line 26.

[0040] The second branch line 26 is longer than the first branch line 25. That is, length L4 > length L3. Therefore, the signal line from the IC 20 to the second radiating element 12B is longer than the signal line from the IC 20 to the first radiating element 12A. As a result, the phase of the RF signal supplied from the IC 20 to the first radiating element 12A is different from the phase of the RF signal supplied from the IC 20 to the second radiating element 12B. In other words, the phases of the RF signals supplied from the IC 20 to the two radiating elements 12 are different from each other.

[0041] The difference in length (L4-L3) between the first branch line 25 and the second branch line 26 can be determined, for example, so as to generate a phase difference equivalent to 1 / 8 to 1 / 2 (e.g., 1 / 4 to 1 / 2) of the designed wavelength of the RF signal. The difference in phase between the RF signal supplied from the IC 20 to the first radiating element 12A and the RF signal supplied from the IC 20 to the second radiating element 12B is, for example, 45 to 180 degrees (preferably 60 to 180 degrees). In other words, the difference in phase between the RF signals supplied from the IC 20 to the two radiating elements 12 (12A, 12B) is, for example, 45 to 180 degrees (preferably 60 to 180 degrees).

[0042] The radiating elements 12 (12A, 12B) receive an RF signal supplied from the signal line 23 and radiate an electromagnetic wave.

[0043] FIG. 4 is a schematic diagram showing a first installation example of the antenna device 100. FIG. 4 shows an example in which the antenna device 100 is installed on a ceiling. As shown in FIG. 4, the antenna device 100 is installed on the top surface 1a (the installation surface) of the ceiling 1. The top surface 1a is, for example, a horizontal plane. The substrate 30 is oriented parallel to the top surface 1a. V1 is a vertical line perpendicular to the top surface 1a and the substrate 30 (first main surface 30a). 101 is an electromagnetic wave radiated from the antenna array 11. R1 indicates the peak direction of the electromagnetic wave 101 (the direction in which the gain is highest). The peak direction of the electromagnetic wave 101 is, for example, the direction of the central axis of the electromagnetic wave 101.

[0044] In the antenna device 100, the phases of the RF signals supplied to the two radiating elements 12 constituting the subarray 10 are different from each other (see FIGS. 2 and 3). Therefore, the peak direction R1 of the electromagnetic wave 101 radiated from the radiating element 12 is inclined with respect to the vertical line V1. The inclination angle A1 of the peak direction R1 with respect to the vertical line V1 is, for example, greater than 0 degrees and not more than 60 degrees. The inclination angle A1 may be not less than 10 degrees and not more than 50 degrees.

[0045] Fig. 5 is a schematic diagram showing a second installation example of the antenna device 100. Fig. 5 shows an example in which the antenna device 100 is installed on a wall. As shown in Fig. 5, the antenna device 100 is installed on a wall surface 2a (the installation surface) of a wall 2. The wall surface 2a is, for example, perpendicular to the horizontal plane. The substrate 30 is oriented parallel to the wall surface 2a. V2 is a vertical line perpendicular to the wall surface 2a and the substrate 30. R2 indicates the peak direction of the electromagnetic wave 101 (the direction in which the gain is highest).

[0046] In the antenna device 100, the phases of the RF signals supplied to the two radiating elements 12 constituting the subarray 10 are different from each other (see FIGS. 2 and 3). Therefore, the peak direction R2 of the electromagnetic wave 101 radiated from the radiating element 12 is inclined with respect to the vertical line V2. The inclination angle A2 of the peak direction R2 with respect to the vertical line V2 is, for example, greater than 0 degrees and not more than 60 degrees. The inclination angle A2 may be not less than 10 degrees and not more than 50 degrees.

[0047] Comparative Example: An antenna device according to a comparative example was considered to clarify the operational effects of the antenna device 100. In the antenna device of the comparative example, the lengths of the signal lines extending from the IC to the two radiating elements constituting the subarray 10 are equal to each other. Therefore, the RF signals supplied from the IC to the two radiating elements are in phase.

[0048] The radiation pattern of the antenna device of the comparative embodiment was obtained. The inclination angle of the peak direction of the electromagnetic wave with respect to the perpendicular line to the installation surface and the board was 0 degrees (Example 1), 10 degrees (Example 2), 20 degrees (Example 3), 30 degrees (Example 4), and 40 degrees (Example 5). The results are shown in Figure 6. Figure 6 is a diagram showing the radiation pattern of the antenna device of the comparative embodiment. C1 in Figure 6 is a trend line passing through the peaks of the radiation patterns of Examples 1 to 5.

[0049] 1, the lengths of the signal lines extending from the IC 20 to the two radiating elements 12 (12A, 12B) constituting the subarray 10 are different from each other. In this embodiment, the phase difference between the RF signals supplied from the IC 20 to the two radiating elements 12 (12A, 12B) is 180 degrees.

[0050] The radiation pattern of the antenna device 100 was obtained. The inclination angle of the peak direction of the electromagnetic wave with respect to a line perpendicular to the installation surface and the substrate 30 was set to 0 degrees (Example 6), 10 degrees (Example 7), 20 degrees (Example 8), 30 degrees (Example 9), and 40 degrees (Example 10). The results are shown in FIG. 7. FIG. 7 is a diagram showing the radiation pattern of the antenna device 100. C2 shown in FIG. 7 is a trend line passing through the peaks of the radiation patterns of Examples 6 to 10. For comparison, FIG. 7 also shows trend line C1 of a comparative example.

[0051] As shown in Fig. 6, the radiation pattern of the comparative example shows a decrease in gain as the tilt angle of the electromagnetic wave peak direction increases (see trend line C1). In contrast, the radiation pattern of the example shown in Fig. 7 shows that the gain does not decrease compared to the radiation pattern of the comparative example even when the tilt angle of the electromagnetic wave peak direction increases (see trend line C2). This result shows that the antenna device 100 can set large tilt angles of the peak directions R1 and R2 while suppressing gain reduction.

[0052] The antenna device 100 can be used for transmitting and receiving electromagnetic waves. The antenna device 100 may be used for either transmission or reception. The antenna device 100 can be used as an antenna device for communications in the field of IoT (Internet of Things) or high-speed wireless communications such as WiGig (Wireless Gigabit).

[0053] [Advantages of the Subarray Antenna Device of the First Embodiment] The antenna device 100 of this embodiment includes a plurality of subarrays 10, an IC 20 that supplies RF signals to the subarrays 10, and a substrate 30 on which the subarrays 10 and the IC 20 are mounted. The peak directions R1 and R2 of the electromagnetic waves 101 radiated from the antenna array 11 are inclined with respect to the vertical lines V1 and V2 (see FIGS. 4 and 5 ). Therefore, even when the antenna device 100 is installed parallel to the installation surface, it can radiate a beam tilted at a sufficient angle. Therefore, the tilt angle of the beam radiation direction can be arbitrarily set within a wide range depending on the environment, usage, etc., of the antenna device 100.

[0054] In the antenna device 100, the phases of the RF signals supplied to the two radiating elements 12 that make up the subarray 10 are different from each other, so that the peak directions R1 and R2 of the electromagnetic wave 101 are inclined with respect to the vertical lines V1 and V2 (see FIGS. 4 and 5). Therefore, by adjusting the phases of the RF signals supplied to the two radiating elements 12 that make up the subarray 10, the peak directions R1 and R2 of the electromagnetic wave 101 can be set arbitrarily. This makes it easy to set the peak directions R1 and R2 of the electromagnetic wave 101.

[0055] In the antenna device 100, the lengths of the signal lines to the two radiating elements 12 that make up the subarray are different from each other, so that the phases of the RF signals supplied to the two radiating elements 12 are different from each other. This configuration makes it possible to adjust the phases of the RF signals supplied to the two radiating elements 12 with a simple structure. This allows the antenna device 100 to be made smaller and at lower cost.

[0056] [Subarray Antenna Apparatus] (Second Embodiment) Fig. 8 is a configuration diagram of an antenna apparatus 200 according to a second embodiment. Fig. 9 is a schematic diagram showing a subarray 210. Components common to the antenna apparatus 100 shown in Fig. 1 are assigned the same reference numerals and description thereof will be omitted.

[0057] 8, the antenna device 200 includes a plurality of subarrays 210, a plurality of ICs 220, and a substrate 30. As shown in Fig. 8 and Fig. 9, the subarray 210 has a configuration in which two subarrays 10 (see Fig. 1) adjacent to each other in the X direction in the first embodiment are electrically connected to each other.

[0058] 8, the subarray 10 in the first column from the left in each row (see FIG. 1) and the subarray 10 in the second column in each row (see FIG. 1) are electrically connected by the connecting line 17 through the signal lines 13, thereby forming a subarray 210. Similarly, the subarrays 10 in the third, fifth, and seventh columns from the left in each row (see FIG. 1) are electrically connected by the connecting line 17 through the signal lines 13, respectively, through the connecting line 17, to the subarrays 10 adjacent thereto on the +X side in each row (i.e., the subarrays 10 in the fourth, sixth, and eighth columns) (see FIG. 1). Thus, the subarrays 210 are formed.

[0059] The multiple subarrays 210 are arranged in a rectangular lattice (matrix) in the X and Y directions to form an antenna array 211. The antenna array 211 is made up of a total of 16 subarrays 210, four in the Y direction and four in the X direction.

[0060] The plurality of subarrays 210 include a first subarray group 210A, a second subarray group 210B, a third subarray group 210C, and a fourth subarray group 210D.

[0061] The first subarray group 210A includes four subarrays 210 located on the +Y side and the -X side of the center. The second subarray group 210B includes four subarrays 210 located on the +Y side and the +X side of the center. The third subarray group 210C includes four subarrays 210 located on the -Y side and the -X side of the center. The fourth subarray group 210D includes four subarrays 210 located on the -Y side and the +X side of the center.

[0062] 8, the antenna device 200 includes four ICs 220. The four ICs 220 are arranged in a rectangular grid (matrix) with two ICs in the Y direction and two ICs in the X direction. The four ICs 220 are designated first to fourth ICs 220A to 220D, respectively.

[0063] The first IC 220A is electrically connected to each of the subarrays 210 included in the first subarray group 210A. The second IC 220B is electrically connected to each of the subarrays 210 included in the second subarray group 210B. The third IC 220C is electrically connected to each of the subarrays 210 included in the third subarray group 210C. The fourth IC 220D is electrically connected to each of the subarrays 210 included in the fourth subarray group 210D.

[0064] 9 , the subarray 210 has a first radiating element group 12C and a second radiating element group 12D. The first radiating element group 12C and the second radiating element group 12D are adjacent to each other in the X direction. The first radiating element group 12C has two radiating elements 12 (a first radiating element 12A1 and a second radiating element 12B1) aligned in the Y direction. The second radiating element group 12D has two radiating elements 12 (a first radiating element 12A2 and a second radiating element 12B2) aligned in the Y direction.

[0065] In the first radiating element group 12C, the signal line from the IC 220 (see FIG. 8) to the first radiating element 12A1 and the signal line from the IC 220 (see FIG. 8) to the second radiating element 12B1 have different lengths. As a result, the phases of the RF signals supplied from the IC 220 to the two radiating elements 12A1 and 12B1 are different from each other. The phase difference between the RF signals supplied from the IC 220 to the two radiating elements 12A1 and 12B1 is, for example, 45 to 180 degrees (preferably 60 to 180 degrees).

[0066] In the second radiating element group 12D, the signal line from the IC 220 (see FIG. 8) to the first radiating element 12A2 and the signal line from the IC 220 (see FIG. 8) to the second radiating element 12B2 have different lengths. As a result, the phases of the RF signals supplied from the IC 220 to the two radiating elements 12A2 and 12B2 are different from each other. The phase difference between the RF signals supplied from the IC 220 to the two radiating elements 12A2 and 12B2 is, for example, 45 to 180 degrees (preferably 60 to 180 degrees).

[0067] The phases of the RF signals supplied to the first radiating elements 12A1 and 12A2 adjacent to each other in the X direction are different from each other. The phase difference between the RF signals supplied from the IC 220 to the two radiating elements 12A1 and 12A2 is, for example, 45 degrees to 180 degrees (preferably 60 degrees to 180 degrees). The phases of the RF signals supplied to the second radiating elements 12B1 and 12B2 adjacent to each other in the X direction are different from each other. The phase difference between the RF signals supplied from the IC 220 to the two radiating elements 12B1 and 12B2 is, for example, 45 degrees to 180 degrees (preferably 60 degrees to 180 degrees).

[0068] Specifically, an example can be given in which the phase difference between the RF signals supplied to the two radiating elements 12A1 and 12B1 in the first radiating element group 12C is 180 degrees, and the phase difference between the RF signals supplied to the two radiating elements 12A2 and 12B2 in the second radiating element group 12D is 180 degrees. The phase difference between the RF signals supplied to the first radiating elements 12A1 and 12A2 adjacent to each other in the X direction is, for example, 180 degrees. The phase difference between the RF signals supplied to the second radiating elements 12B1 and 12B2 adjacent to each other in the X direction is, for example, 180 degrees.

[0069] Fig. 10 is a schematic diagram showing an example of installation of the antenna device 200. In the example shown in Fig. 10, the antenna device 200 is installed on the top surface 1a (installation surface) of the ceiling 1. As shown in Fig. 10, the antenna device 200 can radiate electromagnetic waves 101 in multiple directions.

[0070] The antenna device 200 of this embodiment has the same effects as the antenna device 100 of the first embodiment (see FIG. 1 ). Furthermore, the antenna device 200 has an advantage that the subarray 210 has a plurality of radiating element groups 12C and 12D, and therefore can radiate electromagnetic waves 101 in multiple directions.

[0071] [Subarray Antenna Device] (Third Embodiment) Fig. 11 is a configuration diagram of an antenna device 300 according to a third embodiment. Fig. 12 is a schematic diagram showing a first subarray 210. Fig. 13 is a schematic diagram showing a second subarray 310. Fig. 14 is a schematic diagram showing an installation example of the antenna device 300. Components common to the other embodiments are assigned the same reference numerals and descriptions thereof will be omitted.

[0072] 11, the antenna device 300 includes a plurality of first subarrays 210, a plurality of second subarrays 310, a plurality of ICs 220, and a substrate 30. As shown in Fig. 12, the first subarray 210 has the same configuration as the subarray 210 in the second embodiment (see Fig. 9).

[0073] 13, in the second subarray 310, the IC 220 (see FIG. 11) supplies RF signals to the radiating elements 12 via signal lines 313. In the second subarray 310, in the first radiating element group 12C, the signal line from the IC 220 (see FIG. 11) to the first radiating element 12A1 and the signal line from the IC 220 to the second radiating element 12B1 have the same length. This ensures that the RF signals supplied from the IC 220 to the two radiating elements 12A1 and 12B1 have the same phase.

[0074] In the second subarray 310, in the second radiating element group 12D, the length of the signal line from the IC 220 (see FIG. 11) to the first radiating element 12A2 is the same as the length of the signal line from the IC 220 to the second radiating element 12B2, so that the phases of the RF signals supplied from the IC 220 to the two radiating elements 12A2 and 12B2 are the same.

[0075] 11 , the plurality of first subarrays 210 and the plurality of second subarrays 310 are arranged as a whole in a rectangular lattice pattern (matrix pattern) aligned in the X and Y directions to form an antenna array 311. The antenna array 311 is composed of a total of 16 subarrays 210, 310, with four aligned in the Y direction and four aligned in the X direction.

[0076] Of the 16 subarrays that make up the antenna array 311, the four subarrays aligned along one diagonal line are second subarrays 310. In particular, in FIG. 11 , the subarray in the first column from the right and the first row from the top is the second subarray 310. The subarray in the second column from the right and the second row from the top is also the second subarray 310. The subarray in the third column from the right and the third row from the top is also the second subarray 310. The subarray in the fourth column from the right and the fourth row from the top is also the second subarray 310. The remaining 12 subarrays are first subarrays 210.

[0077] In the antenna device 300, the multiple subarrays that make up the antenna array 311 include a first subarray 210 and a second subarray 310. In the first subarray 210, the phases of the RF signals supplied from the IC 220 to the multiple radiating elements 12 are different. In the second subarray 310, the phases of the RF signals supplied from the IC 220 to the multiple radiating elements 12 are the same.

[0078] Fig. 14 is a schematic diagram showing an installation example of the antenna device 300. In the example shown in Fig. 14, the antenna device 300 is installed on the top surface 1a (installation surface) of a ceiling 1. As shown in Fig. 14, in the antenna device 300, electromagnetic waves 101 are radiated by twelve first subarrays 210. Electromagnetic waves 102 are radiated by four second subarrays 310.

[0079] The antenna device 300 of this embodiment has the same effects as the antenna device 200 of the second embodiment (see FIG. 8 ). Furthermore, the antenna device 300 can radiate electromagnetic waves in the direction of the vertical line V1 as well by the second subarray 310, and therefore can radiate electromagnetic waves over a wide range.

[0080] The second subarrays 310 are arranged in a row along the diagonal lines of the rectangular lattice-shaped antenna array 311. Therefore, the second subarrays 310 are arranged rotationally symmetrically with respect to the center of the antenna array 311. In this way, the second subarrays 310 are arranged without bias within the antenna array 311, so that bias in the radiation direction of the electromagnetic waves 102 from the second subarrays 310 can be reduced.

[0081] The technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, in the antenna devices 100 and 200 shown in Figures 1 and 8, the number of radiating elements 12 constituting the subarrays 10 and 210 is two or four, but the number of radiating elements constituting the subarrays is not limited to this. The number of radiating elements constituting the subarrays may be any number equal to or greater than two.

[0082] When the number of radiating elements constituting the subarray is three or more, it is sufficient that the phases of the RF signals supplied from the IC to the radiating elements are different for two or more of the plurality of radiating elements.

[0083] 2 and 3 , in the antenna device 100, the phases of the RF signals supplied to the two radiating elements 12 are different due to the different lengths of the signal lines, but the method for making the phases of the RF signals supplied to the two radiating elements 12 different is not limited to this. For example, a device for changing the phase of the RF signal (e.g., a phase shifter) may be provided on only one of the paths from the IC to the first radiating element and the path from the IC to the second radiating element. This makes it possible to make the phases of the RF signals supplied to the two radiating elements different from each other even if the lengths of the signal lines from the IC to the two radiating elements are equal.

[0084] In addition, it is possible to replace the components in the above-described embodiments with well-known components as appropriate, and the above-described embodiments and variations may be combined as appropriate, without departing from the spirit of the present invention.

[0085] One aspect of the present invention provides a subarray antenna device capable of setting the radiation direction of a beam with a large inclination.

[0086] DESCRIPTION OF SYMBOLS 1a...Ceiling surface (surface to be installed) 2a...Wall surface (surface to be installed) 10, 210...Subarray 11, 211, 311...Antenna array 12...Radiating element 12A, 12A1, 12A2...First radiating element (radiating element) 12B, 12B1, 12B2...Second radiating element (radiating element) 13, 23...Signal line 20, 220...IC 30...Substrate 100, 200, 300...Antenna device (subarray antenna device) 101, 102...Electromagnetic wave 210...First subarray 310...Second subarray R1...Peak direction of electromagnetic wave V1...Vertical line perpendicular to the substrate

Claims

1. A subarray antenna device comprising: an antenna array composed of multiple subarrays each having a multiple radiating elements; an IC that supplies RF signals to the multiple subarrays; and a substrate on which the multiple subarrays and the IC are mounted, wherein the peak direction of the electromagnetic waves radiated from the antenna array can be tilted relative to a direction perpendicular to the substrate.

2. The subarray antenna device according to claim 1, wherein the phases of the RF signals supplied from said IC to two or more of said plurality of radiating elements constituting said subarray are different.

3. The subarray antenna device according to claim 2, wherein the plurality of radiating elements constituting the plurality of subarrays are electrically connected to the IC via a first signal line and a second signal line, and the length of the first signal line and the length of the second signal line are different.

4. A subarray antenna device as claimed in any one of claims 1 to 3, wherein the plurality of subarrays include a first subarray and a second subarray different from the first subarray, wherein the first subarray has a different phase of the RF signal supplied from the IC to two or more of the plurality of radiating elements, and wherein the second subarray has the same phase of the RF signal supplied from the IC to two or more of the plurality of radiating elements.

5. The subarray antenna device according to claim 4, wherein the plurality of subarrays are arranged in a rectangular lattice pattern, and the second subarray is a plurality of subarrays arranged along diagonals of the antenna array in the rectangular lattice pattern.

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