Antenna device and radio wave control plate

Abstract

This antenna device includes: a phased array antenna including a plurality of antenna elements; and a control unit that is provided in the transmission direction of a transmission radio wave transmitted by the phased array antenna, that is formed so that the transmission phase differs depending on the position where the transmission radio wave is incident, and that controls the transmission radio wave so as to form a prescribed beam pattern. The antenna elements are arranged at an interval wider than the half wavelength of the transmission radio wave.

Description

Antenna device and radio wave control board

[0001] The present disclosure relates to an antenna device and a radio wave control board.

[0002] As described in Patent Document 1, a phased array antenna having a plurality of subarrays is known.

[0003] Special table 2019-503621 publication

[0004] The antenna device of the present disclosure includes a phased array antenna including a plurality of antenna elements, and a control unit that is arranged in the transmission direction of radio waves transmitted by the phased array antenna, and that controls the transmission radio waves so that a transmission phase differs depending on the position at which the transmission radio waves are incident, and so that a predetermined beam pattern is formed, and the plurality of antenna elements are arranged at intervals wider than half the wavelength of the transmission radio waves.

[0005] The radio wave control plate of the present disclosure is arranged in the transmission direction of a transmission radio wave transmitted by a phased array antenna including a plurality of antenna elements, and includes a plurality of unit structures arranged two-dimensionally, and the phases of the plurality of unit structures have a distribution of transmission phases that diffuse the transmission radio wave according to the wavelength of the transmission radio wave.

[0006] FIG. 1 is a diagram for explaining an overview of a phased array antenna. FIG. 2 is a diagram for explaining signal levels of transmission radio waves transmitted by the phased array antenna. FIG. 3 is a diagram for explaining a configuration example of a phased array antenna according to the first embodiment. FIG. 4 is a diagram for explaining signal levels of transmission radio waves transmitted by the phased array antenna according to the first embodiment. FIG. 5 is a diagram for explaining a configuration example of an antenna device according to the first embodiment. FIG. 6 is a diagram for explaining a configuration example of a radio wave control plate according to the first embodiment. FIG. 7 is a diagram for explaining transmission directions of transmission radio waves of a phased array antenna according to a comparative example. FIG. 8 is a diagram for explaining transmission directions of transmission radio waves of the antenna device according to the first embodiment. FIG. 9 is a diagram for explaining simulation conditions for the antenna device according to the first embodiment. FIG. 10 is a diagram for explaining simulation conditions for the antenna device according to the first embodiment. FIG. 11 is a diagram for explaining conditions for calculating the transmission coefficient of the radio wave control plate according to the first embodiment. FIG. 12 is a diagram for explaining simulation conditions for an antenna device according to a first comparative example of the first embodiment. FIG. 13 is a diagram showing simulation results of transmission radio waves of the antenna device according to the first comparative example of the first embodiment. Fig. 14 is a diagram for explaining simulation conditions for an antenna device according to a second comparative example of the first embodiment. Fig. 15 is a diagram showing simulation results of transmitted radio waves from the antenna device according to the second comparative example of the first embodiment. Fig. 16 is a diagram for explaining simulation conditions for the antenna device according to the first embodiment. Fig. 17 is a diagram for explaining a method for setting the phase distribution of the unit structures of the radio wave control plate according to the first embodiment. Fig. 18 is a diagram showing simulation results of transmitted radio waves from the antenna device according to the first embodiment. Fig. 19 is a diagram showing a configuration example of the antenna device according to the second embodiment.

[0007] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to this embodiment, and in the following embodiments, the same components are designated by the same reference numerals, and redundant explanations will be omitted.

[0008] In the following description, an XYZ Cartesian coordinate system is set, and the positional relationship of each part will be described with reference to this XYZ Cartesian coordinate system. The direction parallel to the X axis in a horizontal plane is defined as the X-axis direction, the direction parallel to the Y axis in the horizontal plane perpendicular to the X axis is defined as the Y-axis direction, and the direction parallel to the Z axis perpendicular to the horizontal plane is defined as the Z-axis direction. Furthermore, the plane including the X axis and Y axis will be referred to as the XY plane as appropriate, the plane including the X axis and Z axis will be referred to as the XZ plane as appropriate, and the plane including the Y axis and Z axis will be referred to as the YZ plane as appropriate. The XY plane is parallel to the horizontal plane. The XY plane, XZ plane, and YZ plane are perpendicular to each other.

[0009] [Outline] (Phased Array Antenna) An outline of a phased array antenna will be described with reference to Fig. 1. Fig. 1 is a diagram for explaining the outline of a phased array antenna.

[0010] As shown in FIG. 1, the phased array antenna 10 a includes a substrate 11 , a plurality of antenna elements 12 , and a plurality of phase shifters 13 .

[0011] The substrate 11 is, for example, a dielectric substrate on which a plurality of antenna elements 12 are arranged.

[0012] The multiple antenna elements 12 are arranged in a one-dimensional or two-dimensional array at equal intervals on the substrate 11 in the XY plane. The multiple antenna elements 12 transmit radio waves in a predetermined direction in the +Z-axis direction. The multiple antenna elements 12 receive radio waves arriving from a predetermined direction in the +Z-axis direction. The spacing D1 between the antenna elements 12 is λ / 2, where λ is the wavelength of the radio waves transmitted and received by the antenna elements 12. In the example shown in FIG. 1 , for example, 32 antenna elements 12 are arranged one-dimensionally at λ / 2 intervals along the X-axis direction.

[0013] A plurality of phase shifters 13 are provided for each antenna element 12. Each of the plurality of phase shifters 13 controls the phase of the corresponding antenna element 12. The plurality of phase shifters 13 can change the directivity of the radio waves to be transmitted and received by controlling the phase of the corresponding antenna element 12. In the example shown in Fig. 1, for example, the phase difference between adjacent antenna elements 12 is controlled to be 90°.

[0014] Fig. 2 is a diagram for explaining the signal level of a transmission wave transmitted by a phased array antenna. In Fig. 2, the horizontal axis indicates the direction (deg (degrees)) in which the transmission wave is transmitted, and the vertical axis indicates the array factor (dB (decibels)) normalized by the maximum value. A waveform 201 indicates the signal level of a transmission wave transmitted by the phased array antenna 10a shown in Fig. 1. In the example shown in Fig. 2, as shown in the waveform 201, the phased array antenna 10a is controlled to adjust the phase of each antenna element 12 and transmit the transmission wave in a direction of 30°. Therefore, the waveform 201 has a main lobe 201a in the direction of 30°.

[0015] [First embodiment] A configuration example of a phased array antenna according to the first embodiment will be described with reference to Fig. 3. Fig. 3 is a diagram for explaining a configuration example of a phased array antenna according to the first embodiment.

[0016] 3, the phased array antenna 10 includes a substrate 11, a plurality of antenna elements 12, and a plurality of RFIC chips 14. In FIG. 3, the plurality of phase shifters 13 are omitted.

[0017] As the frequency of the radio waves transmitted and received by the phased array antenna 10 increases, the physical length of a half wavelength of the radio waves decreases. For example, when the frequency of the radio waves is 300 GHz (gigahertz), the half wavelength of the radio waves is 0.5. Therefore, considering a phased array antenna with the same number of antenna elements 12, the area decreases as the frequency increases.

[0018] The phased array antenna 10 typically includes an RFIC (Radio-Frequency Integrated Circuits) chip 14 on the opposite side of the antenna elements 12. It is difficult to miniaturize the RFIC chip 14 in proportion to the wavelength, even as the frequency increases. Therefore, if the elements are arranged to match the size of the RFIC chip 14, the spacing between the antenna elements 12 exceeds λ / 2. In the example shown in FIG. 3 , the spacing D2 between the antenna elements 12 is λ. Specifically, in the example shown in FIG. 3 , 32 antenna elements 12 are arranged one-dimensionally along the X-axis direction at intervals of λ, and the phase difference between adjacent antenna elements 12 is controlled to 180°.

[0019] FIG. 4 is a diagram illustrating the signal level of a transmission wave transmitted by the phased array antenna according to the first embodiment. In FIG. 4, the horizontal axis indicates the direction (deg (degrees)) in which the transmission wave is transmitted, and the vertical axis indicates the array factor (dB (decibels)) normalized by the maximum value. A waveform 202 indicates the signal level of a transmission wave transmitted by the phased array antenna 10 shown in FIG. 3. In the example shown in FIG. 4, as shown in the waveform 202, the phased array antenna 10 is controlled to transmit a transmission wave in a 30° direction by adjusting the phase of each antenna element 12. However, when the spacing between the antenna elements 12 exceeds λ / 2, a grating lobe 202b is generated in a −30° direction in addition to a main lobe 202a in a 30° direction.

[0020] Therefore, the present disclosure provides a phased array antenna 10 having good characteristics even when the spacing between the antenna elements 12 exceeds λ / 2.

[0021] [Antenna Device] A configuration example of the antenna device according to the first embodiment will be described with reference to Fig. 5. Fig. 5 is a diagram showing a configuration example of the antenna device according to the first embodiment.

[0022] As shown in FIG. 5 , the antenna device 100 includes a phased array antenna 10 and a radio wave control plate 20 .

[0023] The radio wave control plate 20 is provided in the transmission direction of the radio waves transmitted by the phased array antenna 10. The radio wave control plate 20 is configured to refract the radio waves transmitted by the phased array antenna 10 in a predetermined direction. The radio wave control plate 20 is a type of control unit that refracts the radio waves transmitted from the phased array antenna 10.

[0024] The radio wave control plate 20 includes a substrate 21 and a plurality of unit structures 30 .

[0025] [Radio wave control board] A configuration example of the radio wave control board according to the first embodiment will be described with reference to Fig. 6. Fig. 6 is a diagram showing a configuration example of the radio wave control board according to the first embodiment.

[0026] The radio wave control plate 20 is a plate-like member configured to transmit radio waves transmitted by the phased array antenna 10 and enable specific beam formation. The radio wave control plate 20 is configured, for example, to refract the transmitted radio waves at a predetermined angle upon receiving the transmitted radio waves transmitted by the phased array antenna 10. The radio wave control plate 20 can be configured, for example, with a metasurface having an array of resonators that change the phase of the incident wave.

[0027] 6, radio wave control plate 20 may include, for example, substrate 21 and unit structures 30a, 30b, 30c, and 30d. When there is no need to distinguish between unit structures 30a to 30d, they will be collectively referred to as unit structures 30.

[0028] The unit structures 30a, 30b, 30c, and 30d may be formed on a substrate 21. The substrate 21 may be, for example, a dielectric substrate made of a dielectric material. The substrate 21 may have, for example, but is not limited to, a rectangular shape. The unit structures 30a, 30b, 30c, and 30d may be arranged two-dimensionally.

[0029] In the radio wave control plate 20, for example, a plurality of unit structures 30a are arranged along the X-axis direction on one tier. On the tier above the tier on which the unit structures 30a are arranged, a plurality of unit structures 30b are arranged along the X-axis direction, for example. On the tier above the tier on which the unit structures 30b are arranged, a plurality of unit structures 30c are arranged along the X-axis direction, for example. On the tier above the tier on which the unit structures 30c are arranged, a plurality of unit structures 30d are arranged along the X-axis direction, for example. In the example shown in FIG. 6 , the unit structures 30a, 30b, 30c, and 30d are arranged periodically along the Y-axis direction.

[0030] Unit structure 30a, unit structure 30b, unit structure 30c, and unit structure 30d are all different in size. In the example shown in Fig. 6, unit structure 30a is the largest, followed by unit structure 30b, unit structure 30c, and unit structure 30d in order of size. That is, radio wave control plate 20 has a structure in which a plurality of unit structures 30 of different sizes are periodically arranged.

[0031] The unit structures 30a to 30d each have a different amount of phase change when radio waves pass through them. That is, the unit structures 30a to 30d are periodically arranged so that there is a gradient in the amount of phase change. The unit structures 30a to 30d each have a rectangular shape, but are not limited to this. By changing the size and shape of the unit structures 30a to 30d, the amount of phase change of the radio waves passing through can be adjusted. In other words, by changing the arrangement method and size of the unit structures 30a to 30d, the radio wave control plate 20 can refract the radio waves transmitted from the phased array antenna 10 in a desired direction or form a desired beam shape.

[0032] 7 is a diagram illustrating the transmission direction of transmission radio waves of a phased array antenna according to a comparative example. As shown in FIG. 7, the phased array antenna 10 transmits transmission radio waves 40 from each antenna element 12 in a direction of, for example, 30°. When the spacing between the antenna elements 12 is λ, the spacing D3 between the transmission radio waves 40 is also λ. In this case, as described above, grating lobes occur in the transmission radio waves 40 in the direction of −30°.

[0033] FIG. 8 is a diagram illustrating the transmission direction of the transmission radio wave of the antenna device according to the first embodiment. The antenna device 100 is configured to refract the transmission radio wave 40 transmitted by the phased array antenna 10, in which the spacing between the antenna elements 12 is λ, and emit the transmitted wave 50 in a direction of 30°. In this case, the phased array antenna 10 transmits the transmission radio wave 40 to the radio wave control plate 20 based on the phase gradient of the unit structures 30 of the radio wave control plate 20, so that the radio wave control plate 20 emits the transmitted wave 50 in a direction of 30°. In other words, the phased array antenna 10 controls the direction in which the transmission radio wave 40 is transmitted in accordance with the phase gradient of the unit structures 30 of the radio wave control plate 20. In the example shown in FIG. 8 , the spacing D4 of the transmitted wave 50 is λ / 2. That is, by including the radio wave control plate 20, the antenna device 100 can transmit transmission radio waves in which the spacing between the antenna elements 12 of the phased array antenna 10 can be considered to be λ / 2. This allows grating lobes to be suppressed even when the spacing between the antenna elements 12 is λ.

[0034] [Simulation] (Simulation Conditions) In the first embodiment, a simulation was performed on the antenna device 100 to confirm its characteristics. Fig. 9 and Fig. 10 are diagrams for explaining the simulation conditions for the antenna device according to the first embodiment.

[0035] In the examples shown in FIGS. 9 and 10, the phased array antenna 10 includes a first antenna element 12 １ and the second antenna element 12 ２ and the third antenna element 12 ３ and the fourth antenna element 12 ４ and the fifth antenna element 12 ５and the sixth antenna element 12 ６ and the seventh antenna element 12 ７ and the eighth antenna element 12 ８ The first antenna element 12 １ to the eighth antenna element 12 ８ When there is no need to distinguish between them, they are collectively referred to as antenna elements 12. That is, the phased array antenna 10 has M=8 antenna elements 12 (M is the number of elements in the phased array antenna). The antenna elements 12 are arranged one-dimensionally at equal intervals along the X-axis direction. The interval D between the antenna elements 12 is λ. The Y coordinate of the center of the phased array antenna 10 is set to 0.

[0036] The radio wave control plate 20 is arranged to be parallel to the phased array antenna 10 in the direction of transmission of the radio wave from the phased array antenna 10. ｍ The position is z ｍ is 10λ. N = 32 × 32 = 1024 unit structures 30 are arranged two-dimensionally at equal intervals on the radio wave control plate 20 (N is the number of elements in the metasurface). The interval between the unit structures 30 is λ / 2. The X and Y coordinates of the radio wave control plate 20 are set to 0.

[0037] 10, a reception point P indicates a reception position of a radio wave transmitted by the antenna device 100. The reception point P is located at a distance d from the origin on the ZX plane. ２，ｋ It is set on the circle C of ２，ｋ is 100m.

[0038] (Calculation Conditions) The calculation conditions for the characteristics of the antenna device 100 will be described. The phased array antenna 10 is port 1. The reception point P is port 2. The angle between the line connecting the origin and reception point P and the Z axis is θ. At this time, the transmission coefficient S21(θ) of the radio wave control plate 20 is calculated using the following equation (1), and the radiation pattern is calculated by changing θ.

[0039]

[0040] Here, s ｉ，ｋrepresents the transmission coefficient of a path from the i-th antenna element 12 of the phased array antenna 10 through the k-th unit structure 30 of the radio wave control plate 20 to the reception point P. ｉ，ｋ is calculated using the following formula (2).

[0041]

[0042] 11 is a diagram for explaining the conditions for calculating the transmission coefficient of the radio wave control plate according to the first embodiment. Transmission point P1 indicates the position of antenna element 12 that transmits the transmitted radio wave. Reception point P2 indicates the reception position of the transmitted wave emitted from radio wave control plate 20. Unit structure 30 is a square with one side of √A. Here, A is the area of ​​unit structure 30. φ ｉ，ｋ is the kth unit structure 30 ｋ is the angle between the direction of the i-th antenna element 12 as seen from the Z axis. ２，ｋ is the angle between the direction of the reception point P as seen from the kth unit feature 30 and the Z axis. ｉ，ｋ is the k-th unit structure 30 ｋ and the i-th antenna element 12 ｉ is the distance between ２，ｋ is the k-th unit structure 30 ｋ and the distance between the receiving point P. ｋ denotes the phase change of the k-th unit structure, and λ is the wavelength of the radio wave transmitted by the phased array antenna 10.

[0043] (Calculation Results) <First Comparative Example> Simulation results of the transmitted radio waves of the antenna device according to the first comparative example will be described. Fig. 12 is a diagram for explaining the simulation conditions of the antenna device according to the first comparative example of the first embodiment. Fig. 13 is a diagram showing the calculation results of |S21| of the antenna device according to the first comparative example of the first embodiment.

[0044] As shown in FIG. 12, an antenna device 100A includes a phased array antenna 10A and a radio wave control plate 20A.

[0045] The phased array antenna 10A includes a substrate 11 and a first antenna element 12. １ to the eighth antenna element 12 ８and a plurality of phase shifters 13. １ to the eighth antenna element 12 ８ are arranged at equal intervals along the X-axis direction. １ to the eighth antenna element 12 ８ The spacing D5 between the adjacent antenna elements 12 is λ / 2. The phase difference between the antenna elements 12 is −90°. １ to the eighth antenna element 12 ８ It is set up for each.

[0046] Radio wave control plate 20A has N=32×32=1024 unit structures 30 arranged two-dimensionally at equal intervals. In the first comparative example, the transmission phases of the unit structures 30 arranged on radio wave control plate 20A are all equal. Therefore, although unit structures 30 are actually arranged on radio wave control plate 20A, they are omitted from the illustration in FIG. 12 .

[0047] In Fig. 13, the horizontal axis represents the direction (deg) in which the transmission radio wave is transmitted, and the vertical axis represents the amplitude (dB) of S21 calculated using equation (1). Waveform 211 represents the signal level of the transmission radio wave transmitted by the antenna device 100A shown in Fig. 12. In the example shown in Fig. 13, as shown in waveform 211, the antenna device 100A is controlled to adjust the phase of each antenna element 12 and transmit the transmission radio wave in a 30° direction. As shown in waveform 211, there is a main lobe 211a in the 30° direction, but no grating lobe is generated.

[0048] <Second Comparative Example> A simulation result of the transmitted radio waves of the antenna device according to the second comparative example will be described. Fig. 14 is a diagram for explaining the simulation conditions of the antenna device according to the second comparative example of the first embodiment. Fig. 15 is a diagram showing the simulation result of the transmitted radio waves of the antenna device according to the second comparative example of the first embodiment.

[0049] As shown in FIG. 14, an antenna device 100B includes a phased array antenna 10B and a radio wave control plate 20B.

[0050] The phased array antenna 10B includes a first antenna element 12 １to the eighth antenna element 12 ８ 12 in that the spacing D6 between adjacent antenna elements 12 is λ. In addition, in phased array antenna 10B, the phase difference between each antenna element 12 is −180°. The configuration of radio wave control plate 20B is the same as that of radio wave control plate 20A shown in FIG.

[0051] In Fig. 15, the horizontal axis represents the direction (deg) in which the transmission radio wave is transmitted, and the vertical axis represents the amplitude (dB) of S21 calculated using equation (1). Waveform 212 represents the signal level of the transmission radio wave transmitted by the antenna device 100B shown in Fig. 14. In the example shown in Fig. 15, as shown in waveform 212, the antenna device 100B is controlled to adjust the phase of each antenna element 12 and transmit the transmission radio wave in a 30° direction. As shown in waveform 212, there is a main lobe 212a in the 30° direction and a grating lobe 212b in the -30° direction.

[0052] First Embodiment A description will be given of simulation results of radio waves transmitted from an antenna device according to a first embodiment. Fig. 16 is a diagram for explaining simulation conditions for the antenna device according to the first embodiment.

[0053] 16, an antenna device 100C includes a phased array antenna 10C and a radio wave control plate 20C. The configuration of the phased array antenna 10C is the same as that of the phased array antenna 10B shown in FIG.

[0054] Radio wave control plate 20C includes substrate 21 and a plurality of unit structures 30. In radio wave control plate 20C, the plurality of unit structures 30 have a distribution of transmission phases that diffuses radio waves transmitted from phased array antenna 10C. Specifically, the phase distribution of the transmission phases of the plurality of unit structures 30 is set according to the wavelength of the transmitted radio waves.

[0055] 17 is a diagram for explaining a method for setting the phase distribution of the unit structure of the radio wave control plate according to the first embodiment. When the distance between the phased array antenna 10C and the radio wave control plate 20C is z ｍ At this time, the position of the focus P3 is set to 2z from the radio wave control plate 20C.ｍ Set it to the z position. ｍ is, for example, 10 m. In this case, the phase distribution of each unit structure 30 is set in accordance with the following formula (3).

[0056]

[0057] Here, x ｍ is the X coordinate of the unit structure 30. ｍ is the Y coordinate of the unit feature 30. Equation (3) is ｍ This is an equation for setting the phase distribution such that: With this phase distribution, radio wave control plate 20C diffuses radio waves from a distance toward phased array antenna 10C, and conversely, can control the radio waves from phased array antenna 10C to form a beam in a predetermined direction. In other words, the presence of radio wave control plate 20C allows an antenna device including phased array antenna 10C and radio wave control plate 20C to operate equivalently in the same way as a phased array antenna with a narrow spacing.

[0058] FIG. 18 is a diagram showing simulation results of the transmitted radio waves of the antenna device according to the first embodiment. In FIG. 18, the horizontal axis indicates the direction (deg) in which the transmitted radio waves are transmitted, and the vertical axis indicates the amplitude (dB) of S21 calculated using equation (1). Waveform 213 indicates the signal level of the transmitted radio waves transmitted by the antenna device 100C shown in FIG. 17. In the example shown in FIG. 17, as shown in waveform 213, the antenna device 100C is controlled to adjust the phase of each antenna element 12 and transmit the transmitted radio waves in a 30° direction. As shown in waveform 213, a main lobe 213a is present in the 30° direction, but no grating lobes are generated. In other words, the antenna device 100C can suppress the grating lobes 212b that were generated in FIG. 15.

[0059] As described above, in the first embodiment, by combining a phased array antenna with a radio wave control plate, it is possible to suppress grating lobes that occur when the spacing between antenna elements of the phased array antenna is equal to or greater than half the wavelength of the transmitted radio wave.

[0060] [Modification of the First Embodiment] A modification of the first embodiment will be described. In the first embodiment, as shown in FIG. 5 , the antenna device 100 is described as including a radio wave control plate 20 that refracts radio waves transmitted by the phased array antenna 10. However, the present disclosure is not limited to this. In the present disclosure, instead of the radio wave control plate, a dielectric (dielectric lens) having a concave lens shape with a thinner thickness near the center than around the periphery may be used. Alternatively, a dielectric plate having a dielectric constant distribution (a lower dielectric constant near the center than around the periphery) may be used. In this modification of the first embodiment, the use of such a concave lens-shaped dielectric allows an antenna device including the phased array antenna 10C and the dielectric lens to operate equivalently to a closely spaced phased array antenna, as in the first embodiment.

[0061] As a result, in the modification of the first embodiment, it is possible to suppress grating lobes that occur when the spacing between antenna elements of a phased array antenna becomes equal to or greater than half the wavelength of the transmitted radio wave.

[0062] [Second embodiment] Fig. 19 illustrates an example of the configuration of an antenna device according to a second embodiment. Fig. 19 is a diagram illustrating an example of the configuration of an antenna device according to a second embodiment.

[0063] As shown in FIG. 19, the antenna device 100D includes a phased array antenna 10D, a radio wave control plate 20D, and a substrate 60.

[0064] The substrate 60 is, for example, a dielectric substrate, and has three regions: a first dielectric layer 61, a second dielectric layer 62, and a third dielectric layer 63.

[0065] The phased array antenna 10D includes a plurality of antenna elements 12, a plurality of phase shifters 13, and a third dielectric layer 63. The third dielectric layer 63 can be regarded as a dielectric substrate on which the plurality of antenna elements 12 are arranged. The configuration of the phased array antenna 10D is the same as the configuration of the phased array antenna 10C shown in FIG.

[0066] Radio wave control board 20D includes a plurality of unit features 30 and a first dielectric layer 61. First dielectric layer 61 can be considered a dielectric substrate on which the plurality of unit features 30 are arranged. Radio wave control board 20D has the same configuration as radio wave control board 20C shown in FIG.

[0067] The second dielectric layer 62 is located between the first dielectric layer 61 and the third dielectric layer 63. The first dielectric layer 61, the second dielectric layer 62, and the third dielectric layer 63 can be considered to be an integrally formed dielectric substrate.

[0068] That is, the antenna device 100D is configured such that the phased array antenna 10D and the radio wave control plate 20D are integrated together. By integrating the phased array antenna 10D and the radio wave control plate 20D, the distance between the phased array antenna 10D and the radio wave control plate 20D is stabilized, and therefore, grating lobes can be appropriately suppressed.

[0069] An antenna device 100 according to a first aspect of the present disclosure includes a phased array antenna 10 including a plurality of antenna elements 12, and a control unit provided in the transmission direction of radio waves transmitted by the phased array antenna 10, which controls the transmission radio waves so that the transmission phase differs depending on the position of incidence of the transmission radio waves and a predetermined beam pattern is formed, and the plurality of antenna elements 12 are arranged at intervals wider than half the wavelength of the transmission radio waves. According to the present disclosure, by providing the control unit in the transmission direction of the transmission radio waves of the phased array antenna 10, it is possible to suppress grating lobes.

[0070] The antenna device 100 according to a second aspect of the present disclosure is the antenna device 100 according to the first aspect, wherein the control unit is a radio wave control plate 20 including a plurality of unit structures 30 arranged two-dimensionally, the plurality of unit structures 30 having a transmission phase distribution that diffuses the transmitted radio waves. According to the present disclosure, it is possible to appropriately suppress grating lobes.

[0071] The antenna device 100 according to a third aspect of the present disclosure is the antenna device 100 according to the first or second aspect, in which the distribution of the transmission phase of the plurality of unit structures 30 is set according to the wavelength of the transmission radio wave. According to the present disclosure, it is possible to appropriately suppress grating lobes.

[0072] In the antenna device 100 according to the fourth aspect of the present disclosure, the control section is a dielectric body having a concave lens shape. According to the present disclosure, it is possible to appropriately suppress grating lobes.

[0073] In the antenna device 100 according to the fifth aspect of the present disclosure, the phased array antenna 10 and the control unit are integrally configured. According to the present disclosure, the antenna device 100 can be configured as a single device.

[0074] A radio wave control plate 20 according to a sixth aspect of the present disclosure is provided in a transmission direction of a transmission radio wave transmitted by a phased array antenna 10 including a plurality of antenna elements 12, and includes a plurality of unit structures 30 arranged two-dimensionally, the phases of the plurality of unit structures 30 having a transmission phase distribution that diffuses the transmission radio wave according to the wavelength of the transmission radio wave. According to the present disclosure, it is possible to suppress grating lobes that occur in the transmission radio wave of the phased array antenna 10.

[0075] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the contents of these embodiments. Furthermore, the above-described components include those that can be easily imagined by a person skilled in the art, those that are substantially the same, and those that are within the so-called equivalent range. Furthermore, the above-described components can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the components can be made without departing from the spirit of the above-described embodiments.

[0076] 10, 10a, 10A, 10B, 10C, 10D Phased array antenna 11, 21, 60 Substrate 12 Antenna element 13 Phase shifter 20, 20A, 20B, 20C, 20D Radio wave control plate 30 Unit structure 40 Transmitted radio wave 50 Transmitted wave 61 First dielectric layer 62 Second dielectric layer 63 Third dielectric layer 100, 100A, 100B, 100C, 100D Antenna device

Claims

1. An antenna device comprising: a phased array antenna including a plurality of antenna elements; and a control unit that is arranged in the transmission direction of radio waves transmitted by the phased array antenna, and that controls the transmission radio waves so that a predetermined beam pattern is formed by forming the transmission phase to differ depending on the position at which the transmission radio waves are incident, wherein the plurality of antenna elements are arranged at intervals wider than half the wavelength of the transmission radio waves.

2. The antenna device according to claim 1, wherein the control unit is a radio wave control plate including a plurality of unit structures arranged two-dimensionally, and the plurality of unit structures have a distribution of transmission phases that diffuses the transmitted radio waves.

3. The antenna device according to claim 2, wherein the distribution of the transmission phase of the plurality of unit structures is set according to the wavelength of the transmission radio wave.

4. The antenna device according to claim 1, wherein the control portion is a dielectric body having a concave lens shape.

5. The antenna device according to claim 1, wherein the phased array antenna and the control unit are integrally configured.

6. A radio wave control plate comprising a plurality of unit structures arranged two-dimensionally in the transmission direction of radio waves transmitted by a phased array antenna including a plurality of antenna elements, wherein the phases of the plurality of unit structures have a distribution of transmission phases that diffuse the transmission radio waves according to the wavelength of the transmission radio waves.

Images