Phased array antenna and phased array antenna device

Abstract

This phased array antenna comprises: a first radiation element group having a plurality of first radiation elements; a sub-array group including a plurality of sub-arrays each having a plurality of second radiation elements; and a phase shifter for determining phases of RF signals that are supplied to the first radiation elements and the second radiation elements. The phase shifter includes a plurality of first phase shifters and a plurality of second phase shifters. The plurality of first radiation elements are electrically connected to the plurality of first phase shifters, respectively. The plurality of sub-arrays are electrically connected to the plurality of second phase shifters, respectively. The phases of the RF signals that are respectively supplied to the plurality of second radiation elements forming the sub-arrays are different, so that the maximum gain direction of the sub-arrays is different from a direction perpendicular to a plane including the plurality of second radiation elements forming the sub-arrays.

Description

Technical Field

[0001] The present invention relates to a phased array antenna and a phased array antenna device. This application claims priority based on Japanese Patent Application No. 2023-111796 filed in Japan on July 6, 2023, and incorporates its content herein.

Background Art

[0002] In the field of high-speed wireless communication, antenna devices capable of beamforming are used. For example, Patent Document 1 discloses an array antenna device that forms a directivity beam whose directivity can be controlled. The array antenna device is installed, for example, on a ceiling, a 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] The above array antenna device has a configuration in which the maximum gain is obtained in the direction perpendicular to the array antenna surface. In a patch antenna generally used for a phased array antenna, when a subarray is not used, the width within which a beam can be radiated is about ±45 degrees. For example, in the above configuration, when a subarray composed of two radiating elements (antennas) is used, a high gain can be obtained because the subarray antenna is also used in a range of about ±20 degrees while covering a range of ±45 degrees.

[0005] For example, when the antenna device is installed at a high position on a wall, it is necessary to cover a wide range from a direction perpendicular to the wall surface to a direction parallel to the wall surface. In that case, it is often required to obtain a higher gain in the direction perpendicular to the wall surface than in the direction parallel to the wall surface. However, if the above array antenna device is tilted to cover directions parallel to the wall, it may not be possible to direct the sub-array beams perpendicular to the wall, resulting in a weakened gain.

[0006] One aspect of the present invention aims to provide a phased array antenna and a phased array antenna device that can arbitrarily set the direction of electromagnetic wave radiation over a wide range and to a high-gain direction with a small number of phase shifters. [Means for solving the problem]

[0007] A phased array antenna according to a first aspect of the present invention comprises a first radiating element group having a plurality of first radiating elements, a subarray group having a plurality of subarrays, each having a plurality of second radiating elements, and a phase shifter that determines the phase of RF signals fed to the first and second radiating elements, wherein the phase shifter comprises a plurality of first phase shifters and a plurality of second phase shifters, each of the plurality of first radiating elements is electrically connected to each of the plurality of first phase shifters, and each of the plurality of subarrays is electrically connected to each of the plurality of second phase shifters, and because the phases of the RF signals fed to each of the plurality of second radiating elements constituting the subarray are different, the direction of the maximum gain of the subarray is different from the direction perpendicular to the plane containing the plurality of second radiating elements forming the subarray.

[0008] In this configuration, the direction of maximum gain for each sub-array is different from the direction perpendicular to the plane containing the multiple second radiating elements forming the sub-array. Therefore, by using the sub-array group and the first radiating element group within a range inclined at a predetermined angle, a high-gain beam can be emitted with fewer phase shifters.

[0009] This configuration includes a first group of radiating elements in addition to the sub-array group. For example, by introducing a phase difference within the first group of radiating elements, electromagnetic waves can be radiated from the first group of radiating elements in directions that cannot be radiated by the sub-array group. Therefore, depending on the usage environment and usage mode of the phased array antenna, it is possible to set a direction for stronger radiation while covering a wide area. Thus, for example, it is possible to freely set the direction with high gain within the coverage area so that a good communication environment can be provided for both users who are far from the installation location of the phased array antenna and users who are close to the installation location.

[0010] A second aspect of the present invention is that, in the phased array antenna of the first aspect, the phase of the RF signal supplied to each of the plurality of second radiating elements constituting the subarray may differ due to differences in the length of the signal lines from the second phase shifter to each of the plurality of second radiating elements constituting the subarray.

[0011] A third aspect of the present invention is a phased array antenna according to the first or second aspect, comprising a plurality of sub-array groups, wherein the plurality of sub-array groups include a first sub-array group and a second sub-array group, and the first radiating element group may be located between the first sub-array group and the second sub-array group.

[0012] A fourth aspect of the present invention is a phased array antenna described in any one of the first to third aspects, wherein the first radiating element and the second radiating element are each capable of transmitting and receiving a plurality of polarizations, and a plurality of first phase shifters and a plurality of second phase shifters corresponding to each of the plurality of polarizations are provided, and the plurality of first phase shifters and the plurality of second phase shifters may each independently control each of the plurality of polarizations.

[0013] A fifth aspect of the present invention is a phased array antenna described in any one of the first to fourth aspects, wherein the first group of radiating elements and the sub-array group are formed on a common substrate, an IC is mounted on the substrate, and the phase shifter may be provided on the IC.

[0014] A sixth aspect of the present invention is a phased array antenna according to the fifth aspect, which may include a plurality of ICs.

[0015] A seventh aspect of the present invention is a phased array antenna according to the fifth or sixth aspect, wherein the substrate may be provided with a frequency converter that converts the frequency of an RF signal input to the IC during transmission or an RF signal output from the IC during reception.

[0016] An eighth aspect of the present invention is that the phased array antenna described in any one of the first to seventh aspects may be installed on the surface to be installed in a position inclined with respect to the horizontal and vertical planes.

[0017] A phased array antenna device according to the ninth aspect of the present invention may comprise a plurality of phased array antennas described in any one of the first to eighth aspects. [Effects of the Invention]

[0018] One aspect of the present invention provides a phased array antenna and a phased array antenna device that can arbitrarily set the direction of electromagnetic wave radiation to a wide range of high-gain directions with a small number of phase shifters. [Brief explanation of the drawing]

[0019] [Figure 1] This is a diagram illustrating the configuration of a phased array antenna according to an embodiment. [Figure 2] This is a schematic diagram showing the first radiating element and the first IC of a phased array antenna according to an embodiment. [Figure 3] This is a schematic diagram showing a subarray and a second IC of a phased array antenna according to an embodiment. [Figure 4] It is a schematic diagram showing an installation example of a phased array antenna according to an embodiment. [Figure 5] It is a schematic diagram of a phased array antenna device according to an embodiment. [Figure 6] It is a schematic diagram showing a first modification example of a phased array antenna according to an embodiment. [Figure 7] It is a schematic diagram showing a first modification example of a phased array antenna according to an embodiment. [Figure 8] It is a schematic diagram showing a second modification example of a phased array antenna according to an embodiment. [Figure 9] It is a schematic diagram showing a second modification example of a phased array antenna according to an embodiment.

Mode for Carrying Out the Invention

[0020] Hereinafter, a phased array antenna and a phased array antenna device according to an embodiment of the present invention will be described based on the drawings.

[0021] [Phased Array Antenna] FIG. 1 is a configuration diagram of a phased array antenna 100 according to an embodiment. As shown in FIG. 1, the phased array antenna 100 includes a first radiation element group 50, a plurality of sub-array groups 40, a plurality of first ICs 60, a plurality of second ICs 20, and a substrate 30. The phased array antenna 100 is also referred to as a "phased array antenna substrate".

[0022] 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 orthogonal to each other. The Z direction is orthogonal to the X direction and the Y direction. A plan view is to view in the Z direction. The Y direction is an example of the first direction. The X direction is an example of the second direction. The plane including the X direction and the Y direction is the "XY plane".

[0023] +X is one direction along the X-axis, which is to the right in Figure 1. -X is the opposite direction to +X. +Y is one direction along the Y-axis, which is upward in Figure 1. -Y is the opposite direction to +Y. +Z is one direction along the Z-axis, which is towards the front of the page in Figure 1. -Z is the opposite direction to +Z.

[0024] In a plan view, the substrate 30 has a rectangular shape with a pair of sides aligned along the X direction and a pair of sides aligned along the Y direction. The first main surface 30a is the +Z side surface of the substrate 30.

[0025] The first radiating element group 50 and the sub-array group 40 are patterned on the first main surface 30a of the substrate 30 based on a predetermined arrangement pattern. Thus, the first radiating element group 50 and the sub-array group 40 are formed on a common substrate 30. The first radiating element group 50 and the sub-array group 40 are formed from a conductive material such as metal (copper, etc.). The first radiating element group 50 and the sub-array group 40 are formed, for example, by an additive method, a subtractive method, or the like. The first group of radiating elements 50 and the sub-array group 40 constitute the antenna array 11.

[0026] The first radiating element group 50 has a plurality of first radiating elements 52. The plurality of first radiating elements 52 are arranged in a rectangular grid (matrix) in the X and Y directions. The plurality of first radiating elements 52 arranged in the Y direction are formed with spacing in the Y direction. The plurality of first radiating elements 52 arranged in the X direction are formed with spacing in the X direction.

[0027] In the example shown in Figure 1, the first radiating element group 50 has a total of 16 first radiating elements 52 arranged in a 2x8 rectangular grid (matrix).

[0028] The multiple first radiating elements 52 include, for example, a first group 51A and a second group 51B. The first group 51A includes a first radiating element 52 located -X to the center of the first radiating element group 50 in the X direction. That is, the first group 51A includes eight first radiating elements 52 that make up the four columns from the left in Figure 1. The second group 51B includes a first radiating element 52 located +X to the center of the first radiating element group 50 in the X direction. That is, the second group 51B includes eight first radiating elements 52 that make up the four columns from the right in Figure 1.

[0029] Figure 2 is a schematic diagram showing the first radiating element 52 and the first IC 60. As shown in Figures 1 and 2, the first radiating element 52 is rectangular in shape, having a pair of sides along the X direction and a pair of sides along the Y direction. The first radiating element 52 is electrically connected to the first IC 60 by a signal line 53. The first RF (Radio Frequency) signal sent from the first IC 60 is supplied to the first radiating element 52 through the signal line 53. The first radiating element 52 receives the first RF signal and radiates electromagnetic waves. The first RF signal is an example of an "RF signal".

[0030] The first IC 60 is an integrated circuit (IC) that processes RF signals. The first IC 60 is mounted, for example, on the side of the substrate 30 opposite to the first main surface 30a. The first IC 60 supplies the first RF signal to the first radiating element 52 via the signal line 53. The first IC 60 is, for example, a BFIC (Beam Forming IC). The first IC 60 is an example of an "IC".

[0031] As shown in Figure 2, the first IC 60 includes a first phase shifter 61 and a first amplifier 62. The first IC 60 may have multiple first phase shifters 61. The first IC 60 may have multiple first amplifiers 62. The first phase shifter 61 can adjust the amount of phase shift of the first RF signal. The first phase shifter 61 can determine the phase of the first RF signal. The first amplifier 62 amplifies the first RF signal as needed. The first phase shifter 61 is an example of a "phase shifter".

[0032] In the example shown in Figure 1, the multiple first IC60s include two first IC60s. The two first IC60s are aligned in the X direction. The two first IC60s are also referred to as first IC60A and first IC60B, respectively. The first IC60A is electrically connected to each of the multiple (eight in this embodiment) first radiating elements 52 included in the first group 51A. The first IC60B is electrically connected to each of the multiple (eight in this embodiment) first radiating elements 52 included in the second group 51B. Note that the number of first IC60s is not limited to two. The number of first IC60s can be one or multiple (any number of two or more).

[0033] The first IC60 comprises a plurality of first phase shifters 61 (see Figure 2). For example, each of the first IC60A and the first IC60B comprises eight first phase shifters 61. Each of the multiple first radiating elements 52 is electrically connected to a different first phase shifter 61. That is, each of the multiple first radiating elements 52 is electrically connected to each of the multiple first phase shifters 61. In this embodiment, the multiple first radiating elements 52 correspond one-to-one with the multiple first phase shifters 61, and each of the multiple first radiating elements 52 is electrically connected to the corresponding first phase shifter 61 from among the multiple first phase shifters 61.

[0034] The subarray group 40 has multiple subarrays 10. The multiple subarray groups 40 include a first subarray group 40A and a second subarray group 40B. Each of the first subarray group 40A and the second subarray group 40B has multiple subarrays 10. The multiple subarrays 10 constituting the first subarray group 40A and the second subarray group 40B are arranged in a rectangular grid (matrix) in the X and Y directions, respectively.

[0035] The first subarray group 40A has a total of 16 subarrays 10 arranged in a 2x8 rectangular grid (matrix). The second subarray group 40B has a total of 16 subarrays 10 arranged in a 2x8 rectangular grid (matrix).

[0036] Multiple sub-arrays 10 aligned in the Y direction are formed with spacing in the Y direction. Multiple sub-arrays 10 aligned in the X direction are formed with spacing in the X direction.

[0037] The multiple subarrays 10 constituting the first subarray group 40A include, for example, a first group 10A and a second group 10B. The first group 10A includes a sub-array 10 located -X side of the center in the X direction of the first sub-array group 40A. That is, the first group 10A includes eight sub-arrays 10 that make up the four leftmost columns in the first sub-array group 40A in Figure 1. The second group 10B includes a sub-array 10 located +X side of the center in the X direction of the first sub-array group 40A. That is, the second group 10B includes eight sub-arrays 10 that make up the four rightmost columns in the first sub-array group 40A in Figure 1.

[0038] The multiple subarrays 10 constituting the second subarray group 40B include, for example, a third group 10C and a fourth group 10D. The third group 10C includes a sub-array 10 located -X side of the center in the X direction of the second sub-array group 40B. That is, the third group 10C includes eight sub-arrays 10 that make up the four leftmost columns in the second sub-array group 40B in Figure 1. The fourth group 10D includes a sub-array 10 located +X side of the center in the X direction of the second sub-array group 40B. That is, the fourth group 10D includes eight sub-arrays 10 that make up the four rightmost columns in the second sub-array group 40B in Figure 1.

[0039] The first sub-array group 40A and the second sub-array group 40B are formed side by side in the Y direction. The first sub-array group 40A and the second sub-array group 40B are formed spaced apart in the Y direction.

[0040] The first sub-array group 40A, the first radiating element group 50, and the second sub-array group 40B are formed in this order, aligned in the Y direction. The first radiating element group 50 is located between the first sub-array group 40A and the second sub-array group 40B. For example, when the phased array antenna 100 is installed on the wall surface 2a of wall 2, it is desirable that the alignment of the first sub-array group 40A, the first radiating element group 50, and the second sub-array group 40B is in the vertical direction.

[0041] Figure 3 is a schematic diagram showing the subarray 10 and the second IC 20. As shown in Figures 1 and 3, the subarray 10 comprises two second radiating elements 12 aligned in the Y direction and a signal line 13. The second radiating element 12 is rectangular in shape, having a pair of sides along the X direction and a pair of sides along the Y direction. The two second radiating elements 12 constituting the subarray 10 are formed adjacent to each other with a gap in the Y direction. One of the two second radiating elements 12 is also called second radiating element 12A. The other of the two second radiating elements 12 is also called second radiating element 12B. Second radiating element 12B is located on the +Y side relative to second radiating element 12A. Second radiating elements 12A and second radiating elements 12B are formed on the first main surface 30a. The first main surface 30a is a plane containing the multiple second radiating elements 12.

[0042] The second radiating element 12 is electrically connected to the second IC 20 by a signal line 13. The second RF signal sent from the second IC 20 is supplied to the second radiating element 12 through the signal line 13. The second radiating elements 12 (12A, 12B) receive the second RF signal and radiate electromagnetic waves. The second RF signal is an example of an "RF signal".

[0043] The signal line 13 comprises a base line 14, a first branch line 15, and a second branch line 16. The base end 14a (first end) of the base line 14 is electrically connected to the second IC 20. The first branch line 15 and the second branch line 16 branch off from the tip 14b (second end, which is the end opposite to the first end) of the base line 14.

[0044] The first branch line 15 extends from the tip 14b of the base line 14 and reaches the second radiating element 12A. The second radiating element 12A is electrically connected to the second IC 20 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.

[0045] 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 second IC 20 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.

[0046] 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 second IC 20 to the second radiating element 12B is longer than the signal line from the second IC 20 to the second radiating element 12A. As a result, the phase of the second RF signal supplied from the second IC 20 to the second radiating element 12A is different from the phase of the second RF signal supplied from the second IC 20 to the second radiating element 12B. In other words, the phases of the second RF signals supplied from the second IC 20 to the two second radiating elements 12 are different from each other.

[0047] 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 equivalent to 1 / 8 to 1 / 2 (e.g., 1 / 4 to 1 / 2) of the wavelength of the design second RF signal is produced. The difference between the phase of the second RF signal supplied from the second IC 20 to the second radiating element 12A and the phase of the second RF signal supplied from the second IC 20 to the second radiating element 12B is, for example, 30 to 180 degrees (preferably 60 to 150 degrees). In other words, the difference in phase of the second RF signals supplied from the second IC 20 to the two second radiating elements 12 (12A, 12B) is, for example, 30 to 180 degrees (preferably 60 to 150 degrees).

[0048] The difference between the phase of the second RF signal supplied to the second radiating element 12A and the phase of the second RF signal supplied to the second radiating element 12B does not have to be the same for all sub-arrays 10. In other words, the phase difference of the second RF signal may be different for multiple sub-arrays 10. To make the phase difference different for multiple sub-arrays 10, the difference in length (L2-L1) between the first branch line 15 and the second branch line 16 should be different for multiple sub-arrays 10. This allows the electromagnetic wave radiation direction from the sub-arrays 10 to be set in multiple directions. By setting the electromagnetic wave radiation direction in multiple directions, a good communication environment can be provided to users over a wide area.

[0049] The second IC20 is an integrated circuit that processes the second RF signal. The second IC20 is mounted, for example, on the side of the substrate 30 opposite to the first main surface 30a. The second IC20 supplies the second RF signal to the second radiating element 12 via the signal line 13. The second IC20 is, for example, a BFIC. The second IC20 is an example of an "IC".

[0050] As shown in Figure 3, the second IC 20 includes a second phase shifter 21 and a second amplifier 22. The second IC 20 may have multiple second phase shifters 21. The second IC 20 may also have multiple second amplifiers 22. The second phase shifter 21 can adjust the amount of phase shift of the second RF signal. The second phase shifter 21 can determine the phase of the second RF signal. The second amplifier 22 amplifies the second RF signal as needed. The second phase shifter 21 is an example of a "phase shifter".

[0051] In the example shown in Figure 1, the multiple second IC20s include four second IC20s. Each of the four second IC20s is also referred to as second IC20A, second IC20B, second IC20C, and second IC20D. Second IC20A and second IC20B are aligned in the X direction. Second IC20C and second IC20D are aligned in the X direction.

[0052] The second IC20A is electrically connected to each of the multiple (eight in this embodiment) subarrays 10 included in the first group 10A. The second IC20B is electrically connected to each of the multiple (eight in this embodiment) subarrays 10 included in the second group 10B. The second IC20C is electrically connected to each of the multiple (eight in this embodiment) subarrays 10 included in the third group 10C. The second IC20D is electrically connected to each of the multiple (eight in this embodiment) subarrays 10 included in the fourth group 10D. Note that the number of 2IC20s is not limited to four. The number of 2IC20s can be one or multiple (any number of two or more).

[0053] The second IC20 is equipped with multiple second phase shifters 21 (see Figure 3). For example, each of the second IC20A to 20D is equipped with eight second phase shifters 21. Each of the multiple sub-arrays 10 is electrically connected to a different second phase shifter 21. That is, each of the multiple sub-arrays 10 is electrically connected to each of the multiple second phase shifters 21. In this embodiment, the multiple sub-arrays 10 correspond one-to-one with the multiple second phase shifters 21, and each of the multiple sub-arrays 10 is electrically connected to the corresponding second phase shifter 21 from among the multiple second phase shifters 21. For example, each of the eight sub-arrays 10 belonging to the first group 10A is electrically connected to each of the eight second phase shifters 21 included in the second IC 20A. Each of the eight sub-arrays 10 belonging to the second group 10B is electrically connected to each of the eight second phase shifters 21 included in the second IC 20B. Each of the eight sub-arrays 10 belonging to the third group 10C is electrically connected to each of the eight second phase shifters 21 included in the second IC 20C. Each of the eight sub-arrays 10 belonging to the fourth group 10D is electrically connected to each of the eight second phase shifters 21 included in the second IC 20D.

[0054] Figure 4 is a schematic diagram showing an example of the installation of the phased array antenna 100. Figure 4 shows an example in which the phased array antenna 100 is installed on wall 2. As shown in Figure 4, the phased array antenna 100 is installed on the wall surface 2a (installation surface) of wall 2. The wall surface 2a is, for example, perpendicular to the horizontal plane. G is the ground. The ground G is horizontal.

[0055] Assume that users U1 and U2 are on the ground G. User U1 is far away from wall 2. User U2 is close to wall 2.

[0056] The phased array antenna 100 is installed such that the first main surface 30a of the substrate 30 is inclined relative to the wall surface 2a. The phased array antenna 100 is installed on the wall surface 2a in an inclined position relative to the horizontal and vertical planes. More specifically, the phased array antenna 100 is installed such that the first main surface 30a of the substrate 30 is angled downwards. The inclination angle of the substrate 30 (first main surface 30a) relative to the wall surface 2a is, for example, greater than 0 degrees and less than 90 degrees. The inclination angle of the phased array antenna 100 is preferably 30 degrees or more and 60 degrees or less.

[0057] 101 is the electromagnetic wave radiated from the subarray group 40 (specifically, the second radiating element 12). V1 is a perpendicular line perpendicular to the substrate 30 (first main surface 30a). R1 ​​indicates the peak direction of the electromagnetic wave 101 (maximum gain direction: the direction in which the gain is highest). The peak direction R1 of the electromagnetic wave 101 is, for example, the direction of the central axis of the electromagnetic wave 101.

[0058] 102 is an electromagnetic wave radiated from the first radiating element group 50 (more specifically, the first radiating element 52). In the example shown in Figure 4, the peak direction of the electromagnetic wave 102 is in a direction with a smaller inclination angle with respect to the wall surface 2a compared to the peak direction R1 of the electromagnetic wave 101.

[0059] In the phased array antenna 100, the phases of the second RF signals fed to the two second radiating elements 12 constituting the sub-array 10 are different (see Figure 3). Therefore, the peak direction R1 of the electromagnetic wave 101 radiated from the sub-array group 40 (second radiating elements 12) is different from the direction perpendicular to the first main plane 30a (the plane containing the second radiating elements 12). That is, the peak direction R1 of the electromagnetic wave 101 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 20 degrees or more and 50 degrees or less.

[0060] The phased array antenna 100 can adjust the direction of electromagnetic wave radiation according to the usage environment and usage pattern by adjusting its installation orientation. For example, to improve the communication environment at a location far from the installation location of the phased array antenna 100, the inclination angle of the substrate 30 relative to the wall surface 2a should be reduced. To improve the communication environment at a location close to the installation location of the phased array antenna 100, the inclination angle of the substrate 30 relative to the wall surface 2a should be increased.

[0061] When the difference between the inclination angle A1 of the peak direction R1 of the electromagnetic wave 101 relative to the vertical line V1 and the maximum radiation angle of the sub-array 10 is large, the grating lobe tends to be large. However, by keeping the power supply to the sub-array 10 low, the grating lobe can be suppressed.

[0062] The phased array antenna 100 can be used for transmitting and receiving electromagnetic waves. The phased array antenna 100 may be used for either transmission or reception only. The phased array antenna 100 can be used for communication in the IoT (Internet of Things) field or for high-speed wireless communication such as WiGig (Wireless Gigabit).

[0063] Figure 5 is a schematic diagram of a phased array antenna device 300 (wireless communication device) according to an embodiment. As shown in Figure 5, the phased array antenna device 300 has a plurality (e.g., two) of phased array antennas 100. The plurality of phased array antennas 100 are installed on the top surface 1a (the surface to be installed) of the ceiling 1 such that their installation orientations (e.g., inclination angles with respect to the top surface 1a) are different from each other. The top surface 1a is, for example, a horizontal plane. The number of phased array antennas 100 in the phased array antenna device 300 may be any number of two or more.

[0064] Since the multiple phased array antennas 100 are installed in different orientations, their electromagnetic wave radiation directions (directions of maximum gain) are also different. Therefore, the phased array antenna device 300 can be configured to emit electromagnetic waves in multiple directions.

[0065] [Effects of the phased array antenna of this embodiment] The phased array antenna 100 of this embodiment comprises a first radiating element group 50, a sub-array group 40, and phase shifters 61 and 21. In the phased array antenna 100, the peak direction R1 of the electromagnetic wave 101 radiated from each sub-array group 40 (specifically, the second radiating element 12) is different from the direction perpendicular to the first main surface 30a (the direction of the vertical line V1) (see Figure 4). Therefore, in the phased array antenna 100, by using the sub-array group 40 and the first radiating element group 50 within a range inclined at a predetermined angle, a high-gain beam can be radiated with fewer phase shifters.

[0066] The phased array antenna 100 has a first radiating element group 50 in addition to the sub-array group 40, so that electromagnetic waves can be radiated from the first radiating element group 50 in directions that cannot be radiated by the sub-array group 40. For example, by creating a phase difference in the multiple first radiating elements 52 that make up the first radiating element group 50 (i.e., by making the phases of the first RF signals fed to the multiple first radiating elements 52 different), electromagnetic waves can be radiated in directions that cannot be radiated by the sub-array group 40. Therefore, depending on the operating environment and usage of the phased array antenna 100, it is possible to set a direction for stronger radiation while covering a wide area.

[0067] In the phased array antenna 100, for example, as shown in Figure 4, communication with user U1, who is far from wall 2 (installation location) where the phased array antenna 100 is installed, can be achieved primarily by using the sub-array group 40 (or both the sub-array group 40 and the first radiating element group 50). Communication with user U2, who is close to wall 2, can be achieved primarily by using the first radiating element group 50. Therefore, the direction with the highest gain can be freely set within the coverage area to provide a good communication environment for both user U1 and user U2.

[0068] In the phased array antenna 100, the phases of the second RF signals fed to the two second radiating elements 12 constituting the sub-array 10 are different, so the peak direction R1 of the electromagnetic wave 101 is inclined relative to the vertical line V1 (see Figure 4). Therefore, the peak direction R1 of the electromagnetic wave 101 can be arbitrarily set by adjusting the phases of the second RF signals fed to the two second radiating elements 12 constituting the sub-array 10. Thus, setting the peak direction R1 of the electromagnetic wave 101 becomes easy.

[0069] In the phased array antenna 100, the phases of the second RF signals fed to the two second radiating elements 12 constituting the subarray 10 differ because the lengths of the signal lines to the two second radiating elements 12 constituting the subarray 10 are different (see Figure 3). With this configuration, the phases of the RF signals fed to the two second radiating elements 12 constituting the subarray 10 can be adjusted with a simple structure. Therefore, the phased array antenna 100 can be made smaller and less expensive.

[0070] In the phased array antenna 100, the first radiating element group 50 is located between the first sub-array group 40A and the second sub-array group 40B (see Figure 1). Therefore, when both sub-array groups 40A, 40B and the first radiating element group 50 are operating simultaneously, the power density near the center of the phased array antenna 100 increases. Consequently, the side lobes of the phased array antenna 100 become smaller. In addition, the radiation pattern in the phased array antenna 100 becomes nearly symmetrical with respect to the main lobe.

[0071] In the phased array antenna 100, the first radiating element group 50 and the sub-array group 40 are formed on a common substrate 30. Therefore, the number of components can be reduced compared to the case where the first radiating element group 50 and the sub-array group 40 are formed on different substrates. Thus, the phased array antenna 100 can be miniaturized.

[0072] In the phased array antenna 100, the second phase shifter 21 is located on the second IC 20 (see Figure 1). Therefore, the second phase shifter 21 can be mounted together with other electronic components (such as the second amplifier 22). This allows for space saving and enables miniaturization of the phased array antenna 100.

[0073] The phased array antenna 100 is equipped with multiple second IC20s (second IC20A to 20D). Therefore, the load on the second IC20 can be reduced compared to when there is only one second IC20. Thus, stable operation can be achieved in the second IC20.

[0074] The phased array antenna device 300 shown in Figure 5 has multiple (e.g., two) phased array antennas 100. The multiple phased array antennas 100 can be configured to have mutually different electromagnetic wave radiation directions (maximum gain directions). This allows the phased array antenna device 300 to have multiple electromagnetic wave radiation directions. Therefore, it is possible to provide a good communication environment to a wide range of users.

[0075] Figures 6 and 7 are schematic diagrams showing a first modified example of the phased array antenna 100. As shown in Figure 6, in this example, the first radiating element 52 is capable of transmitting and receiving multiple polarizations. For example, the first radiating element 52 is a dual-polarization antenna capable of transmitting and receiving two polarizations (vertical polarization and horizontal polarization). The first IC 60 is equipped with two first phase shifters 61 (61A, 61B) and two first amplifiers 62 for one first radiating element 52. Two first phase shifters 61 (61A, 61B) are connected to the first radiating element 52. That is, the first IC 60 has multiple first phase shifters 61 corresponding to each of the multiple polarizations. For example, first phase shifter 61A controls the vertical polarization. First phase shifter 61B controls the horizontal polarization. The two first phase shifters 61 (61A, 61B) independently control each of the multiple polarizations.

[0076] The first phase shifter 61A is electrically connected to the first radiating element 52 via a signal line 53A. The first phase shifter 61B is electrically connected to the first radiating element 52 via a signal line 53B. In the example shown in Figure 6, the signal line 53A is connected to the top edge of the rectangular first radiating element 52. The signal line 53B is connected to the right edge of the first radiating element 52. The top edge and the right edge of the first radiating element 52 are two adjacent edges.

[0077] As shown in Figure 7, in this example, the second radiating element 12 is capable of transmitting and receiving multiple polarizations. For example, the second radiating element 12 is a bipolar antenna capable of transmitting and receiving two polarizations (vertical polarization and horizontal polarization). The second IC 20 has two second phase shifters 21 (21A, 21B) and two second amplifiers 22 for one subarray 110. The second radiating element 12 is connected to two second phase shifters 21 (21A, 21B). That is, IC 20 has multiple second phase shifters 21 corresponding to each of the multiple polarizations. For example, second phase shifter 21A controls the vertical polarization. Second phase shifter 21B controls the horizontal polarization. The two second phase shifters 21 (21A, 21B) independently control each of the multiple polarizations.

[0078] The subarray 110 comprises two second radiating elements 12 (12A, 12B), a signal line 113A, and a signal line 113B. The second phase shifter 21A is electrically connected to the second radiating element 12 (12A, 12B) via the signal line 113A. The signal line 113A comprises a base line 114A, a first branch line 115A, and a second branch line 116A. The base end (first end) of the base line 114A is electrically connected to the second phase shifter 21A. The first branch line 115A and the second branch line 116A branch off from the tip of the base line 114A (the second end, which is the end opposite to the first end). The first branch line 115A is electrically connected to the second radiating element 12A. The second branch line 116A is electrically connected to the second radiating element 12B.

[0079] The second phase shifter 21B is electrically connected to the second radiating element 12 (12A, 12B) via the signal line 113B. The signal line 113B comprises a base line 114B, a first branch line 115B, and a second branch line 116B. The base end (first end) of the base line 114B is electrically connected to the second phase shifter 21B. The first branch line 115B and the second branch line 116B branch off from the tip of the base line 114B (the second end, which is the end opposite to the first end). The first branch line 115B is electrically connected to the second radiating element 12A. The second branch line 116B is electrically connected to the second radiating element 12B.

[0080] In the example shown in Figure 7, branch lines 115A and 116A are connected to the upper side of the rectangular second radiating element 12. Branch lines 115B and 116B are connected to the right side of the second radiating element 12. The upper side and the right side of the second radiating element 12 are two adjacent sides.

[0081] In this example of the phased array antenna 100, the first radiating element 52 is electrically connected to a first phase shifter 61A for vertical polarization and a first phase shifter 61B for horizontal polarization. The second radiating element 12 is electrically connected to a second amplifier 22A for vertical polarization and a second amplifier 22B for horizontal polarization. Therefore, each of the multiple polarizations can be controlled independently.

[0082] Figures 8 and 9 are schematic diagrams showing a second modified example of the phased array antenna 100. As shown in Figure 8, in this example, a frequency converter 63 is connected to the first IC 60. The frequency converter 63 is mounted on the circuit board 30, for example. The frequency converter 63 is provided on the input side (i.e., the output side during reception) of the first IC 60 during transmission. The frequency converter 63 can convert the frequency of the first RF signal input to the first IC 60 during transmission. The frequency converter 63 can convert the frequency of the first RF signal output from the first IC 60 during reception. A filter (e.g., a bandpass filter) that attenuates noise (signals in the frequency band excluding the frequency band of the first RF signal) may be provided between the frequency converter 63 and the first IC 60.

[0083] As shown in Figure 9, in this example, a frequency converter 23 is connected to the second IC 20. The frequency converter 23 is mounted on a circuit board 30, for example. The frequency converter 23 is located on the input side (i.e., the output side during reception) of the second IC 20 during transmission. The frequency converter 23 can convert the frequency of the second RF signal input to the second IC 20 during transmission. The frequency converter 23 can convert the frequency of the second RF signal output from the second IC 20 during reception. A filter (e.g., a bandpass filter) that attenuates noise (signals in the frequency band excluding the frequency band of the second RF signal) may be provided between the frequency converter 23 and the second IC 20.

[0084] In this example, the phased array antenna 100 has frequency converters 63 and 23, allowing the frequencies of the first and second RF signals to be adjusted to any desired value. Normally, RF signal loss is high, but in this example, the phased array antenna 100 can reduce RF signal loss by using the frequency converters 63 and 23 to lower the frequency of the RF signal input to ICs 60 and 20 during transmission (or the RF signal output from ICs 60 and 20 during reception).

[0085] 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, as shown in Figure 3, the phased array antenna 100 has two second radiating elements 12 that make up the sub-array 10. However, the number of second radiating elements that make up the sub-array is not limited to this. The number of second radiating elements that make up the sub-array may be any number of two or more. If the number of second radiating elements that make up the sub-array is three or more, it is sufficient that the phases of the second RF signals fed to at least two of the multiple second radiating elements are different from each other.

[0086] As shown in Figure 3, in the phased array antenna 100, the phases of the second RF signals supplied to the two second radiating elements 12 constituting the sub-array 10 differ because the lengths of the two signal lines from the second IC 20 (second phase shifter 21) to the second radiating elements 12 are different. However, the method for making the phases of the second RF signals supplied to the two second radiating elements 12 constituting the sub-array 10 different is not limited to this. For example, a device that changes the phase of the second RF signal (e.g., a phase shifter, hybrid coupler, rat-race coupler, etc.) may be provided in only one of the paths to either one of the two second radiating elements 12 constituting the sub-array 10 or to the other second radiating element 12 constituting the sub-array 10. This makes it possible to make the phases of the second RF signals supplied to the two second radiating elements 12 different even when the lengths of the signal lines to the two second radiating elements 12 constituting the sub-array 10 are equal.

[0087] As shown in Figure 3, in the phased array antenna 100, the lengths of the signal lines to the two second radiating elements constituting the sub-array 10 are different, but it is not necessary for the lengths of the two signal lines to be different for all sub-arrays 10. For example, the lengths of the two signal lines may be different for only some of the sub-arrays 10, while the lengths of the two signal lines are the same for the other sub-arrays 10.

[0088] 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. [Explanation of symbols]

[0089] 1a...Top surface (mounted surface) 2a...Wall surface (mounted surface) 10...Subarray 12...Second radiating element 13...Signal line 20...Second IC (IC) 21...Second phase shifter (phase shifter) 23...Frequency converter 30...Substrate 30a...First main surface (plane containing multiple second radiating elements) 40...Subarray group 40A...First subarray group 40B...Second subarray group 50...First radiating element group 52...First radiating element 60...First IC (IC) 61...First phase shifter (phase shifter) 63...Frequency converter 100...Phased array antenna 101...Electromagnetic wave 300...Phased array antenna device R1...Direction of electromagnetic wave peak (direction of maximum gain) V1...Vertical line

Claims

1. A group of first radiating elements having multiple first radiating elements, A group of subarrays comprising multiple subarrays, each having multiple second emitting elements, A phase shifter that determines the phase of the RF signals supplied to the first radiating element and the second radiating element, Equipped with, The phase shifter comprises a plurality of first phase shifters and a plurality of second phase shifters. Each of the plurality of first radiating elements is electrically connected to each of the plurality of first phase shifters, Each of the multiple subarrays is electrically connected to each of the multiple second phase shifters. Because the phases of the RF signals supplied to each of the multiple second radiating elements constituting the subarray are different, the direction of maximum gain of the subarray is different from the direction perpendicular to the plane containing the multiple second radiating elements forming the subarray. Due to differences in the length of the signal lines from the second phase shifter to each of the multiple second radiating elements constituting the subarray, the phase of the RF signal supplied to each of the multiple second radiating elements is different. Phased array antenna.

2. The group comprises multiple sub-arrays, The plurality of subarray groups include a first subarray group and a second subarray group, The first group of radiating elements is located between the first sub-array group and the second sub-array group, A phased array antenna according to claim 1.

3. The first radiating element and the second radiating element are each capable of transmitting and receiving multiple polarizations, A plurality of first phase shifters and a plurality of second phase shifters are provided, each corresponding to a plurality of polarizations, and each of the plurality of first phase shifters and the plurality of second phase shifters independently controls each of the plurality of polarizations. A phased array antenna according to claim 1 or 2.

4. The first group of radiating elements and the group of subarrays are formed on a common substrate. An IC is mounted on the aforementioned substrate. The phase shifter is provided in the IC, A phased array antenna according to claim 1 or 2.

5. A plurality of the above ICs are provided, The phased array antenna according to claim 4.

6. The substrate is provided with a frequency converter that converts the frequency of the RF signal input to the IC during transmission, or the RF signal output from the IC during reception. The phased array antenna according to claim 4.

7. It is installed on the surface to be installed in an inclined position with respect to the horizontal and vertical planes. A phased array antenna according to claim 1 or 2.

8. A plurality of the phased array antennas described in claim 1 or 2, Phased array antenna system.

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