Sub-array antenna system

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

Technical Field

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

Background Art

[0002] In the field of high-speed wireless communication, an antenna device provided with beamforming capabilities is used. For example, Patent Document 1 discloses an array antenna device that forms a directive beam with controllable directivity. The array antenna device is installed, for example, on a ceiling, wall, or the like.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

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

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

Means for Solving the Problems

[0006] The subarray antenna device according to the first aspect of the present invention includes an antenna array composed 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 provided, and it is possible to tilt the peak direction of the electromagnetic wave radiated from the antenna array with respect to the direction orthogonal to the substrate.

[0007] According to a 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 sub-array antenna device is installed parallel to the surface to be installed, it can radiate a beam inclined at a sufficient angle. Accordingly, the inclination angle of the beam radiation direction can be arbitrarily set over a wide range depending on the operating environment and usage of the sub-array antenna device.

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

[0009] A third aspect of the present invention is a subarray antenna device according to 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 lengths of the first signal line and the second signal line may be different.

[0010] A fourth aspect of the present invention is a sub-array antenna device according to any one of the first to third aspects, wherein the plurality of sub-arrays may include a first sub-array and a second sub-array different from the first sub-array. The first sub-array may have different phases of the RF signals supplied from the IC to two or more of the plurality of radiating elements. The second sub-array may have the same phases of the RF signals supplied from the IC to two or more of the plurality of radiating elements.

[0011] A fifth aspect of the present invention is a sub-array antenna device according to the fourth aspect, wherein the plurality of sub-arrays are arranged in a rectangular grid, and there are a plurality of second sub-arrays, which may be arranged along the diagonals of the rectangular grid antenna array. [Effects of the Invention]

[0012] One aspect of the present invention provides a sub-array antenna device that allows setting the radiation direction of a beam with a large inclination. [Brief explanation of the drawing]

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

Embodiments for Carrying Out the Invention

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

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

[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 direction and the Y direction are parallel to the first main surface 30a of the substrate 30. The X direction and the Y direction are perpendicular to each other. The Z direction is perpendicular to the X direction and the Y direction. A plan view means looking in the Z direction. The Y direction is an example of the first direction. The X direction is an example of the second direction.

[0017] +X is one direction along the X direction and is the right side in FIG. 1. -X is the direction opposite to +X. +Y is one direction along the Y direction and is the upper side in FIG. 1. -Y is the direction opposite to +Y. +Z is one direction along the Z direction and is the direction of the front side of the paper in FIG. 1. -Z is the direction opposite to +Z.

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

[0019] Multiple sub-arrays 10 are arranged in a rectangular grid (matrix) in the X and Y directions to constitute the antenna array 11. Multiple sub-arrays 10 arranged in the Y direction are spaced apart in the Y direction. Multiple sub-arrays 10 arranged in the X direction are spaced apart in the X direction.

[0020] In the example shown in Figure 1, the antenna array 11 is composed of a total of 32 sub-arrays 10, four in the Y direction and eight in the X direction. That is, the antenna array 11 is composed of sub-arrays 10 arranged in a rectangular grid (matrix) of 4 rows and 8 columns. The four sub-arrays 10 arranged in the Y direction constitute sub-array column 10Y. The antenna array 11 has eight sub-array columns 10Y. The eight sub-arrays 10 arranged in the X direction constitute sub-array row 10X. The antenna array 11 has four sub-array rows 10X.

[0021] The multiple 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 multiple subarrays 10 located on the +Y side and -X side from the center. That is, the first subarray group 10A consists of eight subarrays 10 that are included in the two subarray rows 10X from the top and the four subarray columns 10Y from the left in Figure 1.

[0023] The second subarray group 10B includes multiple subarrays 10 located +Y and +X from the center. That is, the second subarray group 10B consists of eight subarrays 10 included in the top two subarray rows 10X and the right four subarray columns 10Y in Figure 1.

[0024] The third subarray group 10C includes multiple subarrays 10 located -Y and -X from the center. That is, the third subarray group 10C consists of eight subarrays 10 located in the bottom two subarray rows 10X and the left four subarray columns 10Y in Figure 1.

[0025] The fourth subarray group 10D includes multiple subarrays 10 located -Y and +X from the center. That is, the fourth subarray group 10D consists of eight subarrays 10 located in the bottom two subarray rows 10X and the right four subarray columns 10Y in Figure 1.

[0026] IC20 is an integrated circuit (ICU) that processes RF (Radio Frequency) signals. IC20 is mounted, for example, on the side of the substrate 30 opposite to the first main surface 30a. Thus, IC20 is provided on the substrate 30. IC20 supplies RF signals to the radiating element 12 via the signal line 13 (see Figure 2). IC20 is, for example, a BFIC (Beam Forming IC).

[0027] In the example shown in Figure 1, the antenna device 100 includes four IC20s. The four IC20s are arranged in a rectangular grid (matrix) with two in the Y direction and two in the X direction. The four IC20s are designated as the 1st to 4th IC20A to IC20D. The 1st IC20A is electrically connected to each of the multiple subarrays 10 included in the 1st subarray group 10A. The 2nd IC20B is electrically connected to each of the multiple subarrays 10 included in the 2nd subarray group 10B. The 3rd IC20C is electrically connected to each of the multiple subarrays 10 included in the 3rd subarray group 10C. The 4th IC20D is electrically connected to each of the multiple subarrays 10 included in the 4th subarray group 10D.

[0028] Figure 2 is a schematic diagram showing a first example of the subarray 10. As shown in Figure 2, in this example, the subarray 10 comprises two radiating elements 12 aligned 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 constituting the subarray 10 are formed adjacent to each other with a gap in the Y direction. One of the two radiating elements 12 is the first radiating element 12A. The other of the two radiating elements 12 is the second radiating element 12B. The second radiating element 12B is located on the +Y side relative to the first radiating element 12A.

[0030] The signal line 13 comprises a base line 14, a first branch line (first signal line) 15, and a second branch line (second signal line) 16. The base end 14a (first end) of the base line 14 is electrically connected to IC 20. The first branch line 15 and the second branch line 16 are branch lines that branch off from the tip 14b (second end, which is the end opposite to the first end) of the base line 14. The tip 14b of the base line 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 Figure 2, the tip 14b of the base line 14 is located -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 IC20 by the base line 14 and the first branch line 15. The first branch line 15 has an L-shape, comprising a first line 15A running along the Y direction and a second line 15B running along the X direction. The first line 15A extends linearly from the tip 14b of the base line 14 towards the -Y direction. The second line 15B extends linearly from the -Y end of the first line 15A towards the -X direction. 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 IC20 by the base line 14 and the second branch line 16. The second branch line 16 has an L-shape, comprising a first line 16A running along the Y direction and a second line 16B running along the X direction. The first line 16A extends linearly from the tip 14b of the base line 14 towards the +Y direction. The second line 16B extends linearly from the +Y end of the first line 16A towards the -X direction. 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 IC20 to the second radiating element 12B is longer than the signal line from IC20 to the first radiating element 12A. As a result, the phase of the RF signal supplied from IC20 to the first radiating element 12A is different from the phase of the RF signal supplied from IC20 to the second radiating element 12B. In other words, the phases of the RF signals supplied from IC20 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 set such that a phase difference corresponding to, for example, 1 / 8 to 1 / 2 (e.g., 1 / 4 to 1 / 2) of the wavelength of the RF signal under design occurs. The difference in phase between the RF signal supplied from IC 20 to the first radiating element 12A and the RF signal supplied from 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 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 emit electromagnetic waves.

[0036] Figure 3 is a schematic diagram showing a second example of the subarray 10. As shown in Figure 3, in this example, the subarray 10 comprises two radiating elements 12 aligned in the Y direction and a signal line 23. Components common to the first example (see Figure 2) are given the same reference numerals and their explanation is omitted.

[0037] The signal line 23 comprises a base line 14, a first branch line 25 (first signal line), and a second branch line 26 (second signal line). The first branch line 25 and the second branch line 26 are branch lines that branch off from the tip 14b (the second end, which is the end opposite to 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 IC 20 by the base line 14 and the first branch line 25. The first branch line 25 has an L-shape, consisting of a first line 25A running along the Y direction and a second line 25B running along the X direction. The first line 25A extends linearly from the tip 14b of the base line 14 towards the -Y direction. The second line 25B extends linearly from the -Y end of the first line 25A towards the -X direction. 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 and reaches the second radiating element 12B. The second radiating element 12B is electrically connected to IC 20 by 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 in a straight line to the +Y side from the tip 14b of the base line 14. The second line 26B extends in a straight line to the +X side from the +Y side tip of the first line 26A. The third line 26C extends in a straight line to the +Y side from the +X side tip of the second line 26B. The fourth line 26D extends in a straight line to the -X side from the +Y side tip of the third line 26C. 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 IC20 to the second radiating element 12B is longer than the signal line from IC20 to the first radiating element 12A. As a result, the phase of the RF signal supplied from IC20 to the first radiating element 12A is different from the phase of the RF signal supplied from IC20 to the second radiating element 12B. In other words, the phases of the RF signals supplied from IC20 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 set such that a phase difference corresponding to, for example, 1 / 8 to 1 / 2 (e.g., 1 / 4 to 1 / 2) of the wavelength of the RF signal under design occurs. The difference in phase between the RF signal supplied from IC 20 to the first radiating element 12A and the RF signal supplied from 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 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 emit electromagnetic waves.

[0043] Figure 4 is a schematic diagram showing a first installation example of the antenna device 100. Figure 4 shows an example in which the antenna device 100 is installed on the ceiling. As shown in Figure 4, the antenna device 100 is installed on the top surface 1a (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 (see Figures 2 and 3). Therefore, the peak direction R1 of the electromagnetic wave 101 radiated from the radiating elements 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 60 degrees or less. The inclination angle A1 may also be greater than 10 degrees and 50 degrees or less.

[0045] Figure 5 is a schematic diagram showing a second installation example of the antenna device 100. Figure 5 shows an example where the antenna device 100 is installed on a wall. As shown in Figure 5, the antenna device 100 is installed on the wall surface 2a (the surface to be installed) of 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 (see Figures 2 and 3). Therefore, the peak direction R2 of the electromagnetic wave 101 radiated from the radiating elements 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 60 degrees or less. The inclination angle A2 may also be greater than 10 degrees and 50 degrees or less.

[0047] (Comparative example) To clarify the effects of the antenna device 100, a comparative antenna device was considered. In the comparative antenna device, the lengths of the signal lines from the IC to the two radiating elements constituting the subarray 10 are equal. Therefore, the RF signals supplied from the IC to the two radiating elements are in phase.

[0048] The radiation patterns of the comparative antenna devices were obtained. The inclination angle of the electromagnetic wave peak direction relative to the vertical line perpendicular to the mounting surface and substrate was set to 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 shows the radiation patterns of the antenna devices related to the comparative configuration. C1 shown in Figure 6 is a trend line passing through the peaks of the radiation patterns of Examples 1 to 5.

[0049] (Examples) In the antenna device 100 shown in Figure 1, the lengths of the signal lines starting from IC 20 and reaching the two radiating elements 12 (12A, 12B) that constitute the subarray 10 are different. In this embodiment, the phase difference of the RF signals supplied from IC 20 to the two radiating elements 12 (12A, 12B) is 180 degrees.

[0050] The radiation patterns of the antenna device 100 were obtained. The inclination angle of the electromagnetic wave peak direction relative to a vertical line perpendicular to the mounting 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 Figure 7. Figure 7 shows the radiation patterns of the antenna device 100. C2 shown in Figure 7 is a trend line passing through the peaks of the radiation patterns of Examples 6 to 10. For comparison, the trend line C1 of a comparative example is also shown in Figure 7.

[0051] As shown in Figure 6, in the comparative example, the radiation pattern shows that the gain decreases as the slope angle in the direction of the electromagnetic wave peak increases (see trend line C1). In contrast, the radiation pattern in the embodiment shown in Figure 7 did not show a decrease in gain even when the slope angle in the direction of the electromagnetic wave peak increased, compared to the radiation pattern in the comparative example (see trend line C2). These results show that the antenna device 100 can set a large tilt angle for the peak directions R1 and R2 while suppressing a decrease in gain.

[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 IoT (Internet of Things) field, or for high-speed wireless communication such as WiGig (Wireless Gigabit).

[0053] [Effects of the sub-array antenna device of the first embodiment] The antenna device 100 of this embodiment comprises a plurality of sub-arrays 10, an IC 20 that supplies RF signals to the sub-arrays 10, and a substrate 30 on which the sub-arrays 10 and 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 Figures 4 and 5). Therefore, even when the antenna device 100 is installed parallel to the surface to be installed, it can radiate a beam inclined at a sufficient angle. Thus, the inclination angle of the beam radiation direction can be arbitrarily set over a wide range depending on the usage environment and usage mode of the antenna device 100.

[0054] 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, so the peak directions R1 and R2 of the electromagnetic wave 101 are inclined with respect to the vertical lines V1 and V2 (see Figures 4 and 5). Therefore, the peak directions R1 and R2 of the electromagnetic wave 101 can be arbitrarily set by adjusting the phases of the RF signals supplied to the two radiating elements 12 constituting the subarray 10. Thus, setting the peak directions R1 and R2 of the electromagnetic wave 101 becomes easy.

[0055] In the antenna device 100, the phases of the RF signals supplied to the two radiating elements 12 are different because the lengths of the signal lines to the two radiating elements 12 constituting the subarray are different. With this configuration, the phases of the RF signals supplied to the two radiating elements 12 can be adjusted with a simple structure. Therefore, the antenna device 100 can be made smaller and less expensive.

[0056] [Sub-array antenna device] (Second embodiment) Figure 8 is a configuration diagram of the antenna device 200 according to the second embodiment. Figure 9 is a schematic diagram showing the sub-array 210. Components common to the antenna device 100 shown in Figure 1 are denoted by the same reference numerals and their explanation is omitted.

[0057] As shown in Figure 8, the antenna device 200 comprises a plurality of sub-arrays 210, a plurality of ICs 220, and a substrate 30. As shown in Figures 8 and 9, the subarray 210 is configured such that two adjacent subarrays 10 (see Figure 1) in the X direction in the first embodiment are electrically connected to each other.

[0058] More specifically, in Figure 8, the sub-array 10 in the first column from the left in each row (see Figure 1) and the sub-array 10 in the second column in each row (see Figure 1) are electrically connected by signal lines 13 and connecting lines 17. This forms a sub-array 210. Similarly, each of the sub-arrays 10 in the 3rd, 5th, and 7th columns from the left in each row (see Figure 1) and the adjacent sub-array 10 on the +X side in each row (i.e., each of the sub-arrays 10 in the 4th, 6th, and 8th columns) (see Figure 1) are electrically connected by signal lines 13 and connecting lines 17. This forms a sub-array 210.

[0059] Multiple sub-arrays 210 are arranged in a rectangular grid (matrix) in the X and Y directions to form the antenna array 211. The antenna array 211 is composed of a total of 16 sub-arrays 210, four in the Y direction and four in the X direction.

[0060] The multiple 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 sub-array group 210A includes four sub-arrays 210 located +Y and -X from the center. The second sub-array group 210B includes four sub-arrays 210 located +Y and +X from the center. The third sub-array group 210C includes four sub-arrays 210 located -Y and -X from the center. The fourth sub-array group 210D includes four sub-arrays 210 located -Y and +X from the center.

[0062] In the example shown in Figure 8, the antenna device 200 is equipped with four IC220s. The four IC220s are arranged in a rectangular grid (matrix) with two in the Y direction and two in the X direction. The four IC220s are designated as the 1st to 4th IC220A to IC220D, respectively.

[0063] The first IC220A is electrically connected to each of the multiple subarrays 210 included in the first subarray group 210A. The second IC220B is electrically connected to each of the multiple subarrays 210 included in the second subarray group 210B. The third IC220C is electrically connected to each of the multiple subarrays 210 included in the third subarray group 210C. The fourth IC220D is electrically connected to each of the multiple subarrays 210 included in the fourth subarray group 210D.

[0064] As shown in Figure 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 in the X direction. The first radiating element group 12C has two radiating elements 12 (first radiating element 12A1 and second radiating element 12B1) aligned in the Y direction. The second radiating element group 12D has two radiating elements 12 (first radiating element 12A2 and second radiating element 12B2) aligned in the Y direction.

[0065] In the first radiating element group 12C, the signal line from IC220 (see Figure 8) to the first radiating element 12A1 and the signal line from IC220 (see Figure 8) to the second radiating element 12B1 have different lengths. As a result, the phases of the RF signals supplied from IC220 to the two radiating elements 12A1 and 12B1 are different. The phase difference of the RF signals supplied from IC220 to the two radiating elements 12A1 and 12B1 is, for example, 45 degrees to 180 degrees (preferably 60 degrees to 180 degrees).

[0066] In the second radiating element group 12D, the signal line from IC220 (see Figure 8) to the first radiating element 12A2 and the signal line from IC220 (see Figure 8) to the second radiating element 12B2 are of different lengths. As a result, the phases of the RF signals supplied from IC220 to the two radiating elements 12A2 and 12B2 are different. The phase difference of the RF signals supplied from IC220 to the two radiating elements 12A2 and 12B2 is, for example, 45 degrees to 180 degrees (preferably 60 degrees to 180 degrees).

[0067] The phases of the RF signals supplied to adjacent first radiating elements 12A1 and 12A2 in the X direction are different from each other. The phase difference of the RF signals supplied from IC220 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 adjacent second radiating elements 12B1 and 12B2 in the X direction are different from each other. The phase difference of the RF signals supplied from IC220 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 of 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 of 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 of the RF signals supplied to adjacent first radiating elements 12A1 and 12A2 in the X direction is, for example, 180 degrees. The phase difference of the RF signals supplied to adjacent second radiating elements 12B1 and 12B2 in the X direction is, for example, 180 degrees.

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

[0070] The antenna device 200 of this embodiment provides the same effects as the antenna device 100 of the first embodiment (see Figure 1). Furthermore, the antenna device 200 has the advantage that, because the subarray 210 has multiple groups of radiating elements 12C and 12D, it can radiate electromagnetic waves 101 in multiple directions.

[0071] [Sub-array antenna device] (Third embodiment) Figure 11 is a configuration diagram of the antenna device 300 according to the third embodiment. Figure 12 is a schematic diagram showing the first sub-array 210. Figure 13 is a schematic diagram showing the second sub-array 310. Figure 14 is a schematic diagram showing an example of the installation of the antenna device 300. Components common to other embodiments are denoted by the same reference numerals and their description is omitted.

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

[0073] As shown in Figure 13, in the second subarray 310, IC220 (see Figure 11) supplies an RF signal to the radiating element 12 via the signal line 313. In the second sub-array 310, in the first radiating element group 12C, the length of the signal line from IC220 (see Figure 11) to the first radiating element 12A1 and the length of the signal line from IC220 to the second radiating element 12B1 are the same. As a result, the phases of the RF signals supplied from IC220 to the two radiating elements 12A1 and 12B1 are the same.

[0074] In the second sub-array 310, in the second radiating element group 12D, the signal line from IC220 (see Figure 11) to the first radiating element 12A2 and the signal line from IC220 to the second radiating element 12B2 are of the same length. As a result, the phases of the RF signals supplied from IC220 to the two radiating elements 12A2 and 12B2 are the same.

[0075] As shown in Figure 11, multiple first subarrays 210 and multiple second subarrays 310 are arranged together in a rectangular grid (matrix) in the X and Y directions to form the antenna array 311. The antenna array 311 is composed of a total of 16 subarrays 210 and 310, four in the Y direction and four in the X direction.

[0076] Of the 16 subarrays that make up antenna array 311, the four subarrays aligned along one diagonal constitute the second subarray 310. Specifically, in Figure 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 constitute the first subarray 210.

[0077] In the antenna device 300, the multiple sub-arrays constituting the antenna array 311 include a first sub-array 210 and a second sub-array 310. In the first sub-array 210, the phases of the RF signals supplied from IC 220 to the multiple radiating elements 12 are different. In the second sub-array 310, the phase of the RF signals supplied from IC220 to the multiple radiating elements 12 is the same.

[0078] Figure 14 is a schematic diagram showing an example of the installation of the antenna device 300. In the example shown in Figure 14, the antenna device 300 is installed on the top surface 1a (the surface to be installed) of the ceiling 1. As shown in Figure 14, in the antenna device 300, electromagnetic waves 101 are radiated by 12 first sub-arrays 210. Electromagnetic waves 102 are radiated by 4 second sub-arrays 310.

[0079] The antenna device 300 of this embodiment provides the same effects as the antenna device 200 of the second embodiment (see Figure 8). Furthermore, the antenna device 300 can also radiate electromagnetic waves in the direction of the vertical line V1 by the second sub-array 310, thus enabling it to radiate electromagnetic waves over a wide area.

[0080] The second sub-array 310 is arranged in a single row along the diagonal of the rectangular grid-shaped antenna array 311. Therefore, the second sub-array 310 is positioned so as to be rotationally symmetric with respect to the center of the antenna array 311. In this way, the second sub-array 310 is evenly distributed within the antenna array 311, which reduces the bias in the direction of radiation of electromagnetic waves 102 from the second sub-array 310.

[0081] The technical scope of the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention. For example, in the antenna devices 100 and 200 shown in Figures 1 and 8, the number of radiating elements 12 constituting the sub-arrays 10 and 210 is 2 or 4, but the number of radiating elements constituting the sub-arrays is not limited to this. The number of radiating elements constituting the sub-arrays may be any number of 2 or more.

[0082] If 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 multiple radiating elements.

[0083] As shown in Figures 2 and 3, in the antenna device 100, the phases of the RF signals supplied to the two radiating elements 12 differ due to the different lengths of the signal lines. However, 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 that changes the phase of the RF signal (e.g., a phase shifter) may be provided in only one of the paths from the IC to the first radiating element or 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 even when the lengths of the signal lines from the IC to the two radiating elements are equal.

[0084] Furthermore, without departing from the spirit of the present invention, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described embodiments and modifications may be combined as appropriate. [Industrial applicability]

[0085] One aspect of the present invention provides a sub-array antenna device that allows setting the radiation direction of a beam with a large inclination. [Explanation of Symbols]

[0086] 1a...Top surface (installation surface) 2a...Wall surface (installation surface) 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...Perpendicular line perpendicular to the substrate

Claims

1. An antenna array composed of multiple subarrays having multiple radiating elements, An IC that supplies RF signals to multiple subarrays, The system comprises a substrate on which a plurality of the subarrays and the ICs are provided, The peak direction of the electromagnetic waves radiated from the antenna array can be tilted with respect to the direction perpendicular to the substrate. The phases of the RF signals supplied from the IC to two or more of the multiple radiating elements constituting the subarray are different from each other. The multiple radiating elements constituting the multiple subarrays are connected to a first signal line and a second signal line branched in parallel from each of the radiating elements, and are electrically connected to the IC via the first signal line and the second signal line. The length of the first signal line and the length of the second signal line are different. Sub-array antenna system.

2. An antenna array comprising a plurality of subarrays having a plurality of radiating elements, An IC that supplies RF signals to multiple subarrays, The system comprises a substrate on which a plurality of the subarrays and the ICs are provided, The peak direction of the electromagnetic waves radiated from the antenna array can be tilted with respect to the direction perpendicular to the substrate. The plurality of subarrays each include a first subarray and a second subarray that is different from the first subarray. The first subarray is configured such that the phases of the RF signals supplied from the IC to two or more of the multiple radiating elements are different from each other. The second subarray has the same phase of the RF signals supplied from the IC to two or more of the multiple radiating elements. Sub-array antenna system.

3. The plurality of subarrays are arranged in a rectangular grid, There are multiple second sub-arrays, which are arranged along the diagonals of the rectangular grid-shaped antenna array. The subarray antenna device according to claim 2.

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