antenna module

Abstract

The technical problem of the present application is to improve the radiation characteristics of an antenna member without adding a virtual antenna element. The antenna module (1) of the present application includes an antenna member (3) including a plurality of antenna elements (14) and a ground conductor surrounding each of the plurality of antenna elements (14), and a metal member (20) disposed in contact with the ground conductor surrounding an outermost antenna element of the plurality of antenna elements (14). Thus, the radiation characteristics of the antenna member (3) can be improved without adding a virtual antenna element.

Description

Technical Field

[0001] This invention relates to antenna modules. Background Technology

[0002] Patent Document 1 discloses an antenna component that improves radiation characteristics by arranging a virtual antenna element adjacent to the outermost antenna element among a plurality of antenna elements.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: International Publication No. WO2019 / 146183 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] However, when adding virtual antenna elements to improve radiation characteristics, there are problems with the increase in the number of components and manufacturing costs.

[0008] Therefore, the object of the present invention is to improve the radiation characteristics of an antenna component without adding virtual antenna elements.

[0009] Methods for solving problems

[0010] An antenna module according to one embodiment of the present invention includes: an antenna component comprising a plurality of antenna elements and ground conductors respectively surrounding the plurality of antenna elements; and a metal member disposed adjacent to the ground conductor surrounding the outermost antenna element among the plurality of antenna elements.

[0011] The effects of the invention

[0012] According to the present invention, the radiation characteristics of an antenna component can be improved without adding virtual antenna elements. Attached Figure Description

[0013] Figure 1 These are diagrams illustrating the structure of an antenna module 1 according to one embodiment. (a) is a schematic perspective view, and (b) is a schematic top view.

[0014] Figure 2 This is a schematic three-dimensional view of antenna element 10.

[0015] Figure 3 This is a schematic perspective view of metal component 20.

[0016] Figure 4 This is a schematic perspective view of the metal component 20 in the modified example.

[0017] Figure 5 This is a partial perspective view of the modified metal component 20.

[0018] Figure 6 This is a schematic diagram illustrating the internal structure of the antenna element 10.

[0019] Figure 7 This is a circuit diagram of antenna element 10, showing the portion associated with one antenna element 14.

[0020] Figure 8 This is a schematic cross-sectional view showing an example of an electronic component 40 being housed in a cavity 22 of a metal component 20.

[0021] Figure 9 This is a schematic perspective view illustrating the structure of the antenna module 1a in the first modified example.

[0022] Figure 10 This is a schematic top view used to illustrate the structure of the antenna module 1b in the second variation.

[0023] Figure 11 The graphs show the results of Example 1, (a) showing the radiation pattern without the metal component 20, and (b) showing the radiation pattern with the metal component 20.

[0024] Figure 12 This is a graph showing the results of Example 2.

[0025] Figure 13 This is a graph showing the results of Example 3.

[0026] Explanation of reference numerals in the attached figures

[0027] 1, 1a, 1b Antenna Modules

[0028] 2. Circuit substrate

[0029] 3 Antenna components

[0030] 10 antenna elements

[0031] 11, 12 Dielectric layers

[0032] 13. Circular pattern

[0033] 14 Antenna Components

[0034] 15, 18 Ground pillars

[0035] 16V, 16H power supply pattern

[0036] 17V, 17H power supply column

[0037] 19V, 19H filter circuit

[0038] 20 Metal components

[0039] 21. Upper surface

[0040] 22 Hollow

[0041] 31 signal terminal

[0042] 32 Grounding terminal

[0043] 40 Electronic components

[0044] 41 terminal electrodes

[0045] 42. Land pattern

[0046] 43, 43G conductor patterns

[0047] 51-54 Metal components

[0048] 60 antenna elements

[0049] 70 Metal components

[0050] 81 Antenna Layer

[0051] 82 Filtering Layer

[0052] 83 Wiring Layer

[0053] G1, G2 grounding patterns Detailed Implementation

[0054] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0055] Figure 1 These are diagrams illustrating the structure of an antenna module 1 according to one embodiment. (a) is a schematic perspective view, and (b) is a schematic top view.

[0056] like Figure 1 As shown, one embodiment of the antenna module 1 includes: an antenna component 3 composed of a plurality of antenna elements 10 mounted on a circuit substrate 2, and a surrounding metal member 20 surrounding the plurality of antenna elements 10. Figure 1 In the example shown, four antenna elements 10 are arranged in an array along the x and y directions, but the number and arrangement of antenna elements 10 are not limited to this. The gap between adjacent antenna elements 10 in the x or y direction is S1. Furthermore, the gap between the antenna component 3 and the metal member 20 in the x or y direction is S2.

[0057] Figure 2 This is a schematic three-dimensional view of antenna element 10.

[0058] like Figure 2 As shown, the antenna element 10 includes: dielectric layers 11 and 12; four antenna elements 14 formed on the dielectric layer 11; a plurality of grounding posts 15 surrounding the antenna elements 14; and an annular pattern 13 connecting the plurality of grounding posts 15 to each other. Thus, the antenna component 3 includes a total of 16 antenna elements 14. Figure 1 In the example shown, the four antenna elements 14 are arranged in an array in the xy direction, but the number and arrangement of antenna elements 14 included in one antenna unit 10 are not limited to this. Thus, by dividing the antenna component 3, which consists of 16 antenna elements 14, into four antenna units 10, poor connections caused by the difference in thermal expansion coefficients between the antenna unit 10 and the circuit substrate 2 can be prevented. Furthermore, by integrating the four antenna elements 14 into one antenna unit 10, the increase in the number of components can also be suppressed. Additionally, the multiple grounding posts 15 and the annular pattern 13 are examples of grounding conductors.

[0059] Figure 3 This is a schematic perspective view of metal component 20.

[0060] like Figure 3 As shown, the metal component 20 is a frame-like structure made of metal materials such as copper. The metal component 20 can be entirely made of metal, or it can have internal openings; at least for the xy plane (upper surface 21) facing the same direction as the antenna element 14, it needs to be made of metal. Figure 4 In the example shown, a cavity 22 is provided in the metal component 20, and the portion constituting the xy plane (lower surface) facing the circuit substrate 2 is removed. The metal component 20 can also be... Figure 4 The structure shown is as described. Furthermore, the xz and yz planes of the metal component 20 do not need to be flat surfaces; they can also be as shown... Figure 5 As shown, it is finned. This improves heat dissipation performance.

[0061] Figure 6 This is a schematic diagram illustrating the internal structure of the antenna unit 10, showing schematically its mounting on the circuit substrate 2.

[0062] like Figure 6 As shown, the antenna element 10 has: an antenna layer 81, a filter layer 82, and a wiring layer 83 stacked between the filter layer 82 and the antenna layer 81.

[0063] Antenna layer 81 includes a dielectric layer 11 and multiple antenna elements 14 embedded in the dielectric layer 11. Furthermore, in a top view viewed from the stacking direction (z-direction), antenna layer 81 has multiple grounding posts 15 and an annular pattern 13 surrounding the antenna elements 14. The grounding posts 15 are columnar conductors extending in the z-direction, penetrating the dielectric layer 11. Filter layer 82 is composed of a dielectric layer 12 and conductor patterns or chip components embedded in the dielectric layer 12. The dielectric material constituting the dielectric layer 12 has a higher dielectric constant than the dielectric material constituting the dielectric layer 11. LTCC can be used as the material for dielectric layers 11 and 12. Filter layer 82 forms a mounting surface relative to the circuit substrate 2. Signal terminals 31V and 31H and multiple grounding terminals 32 are provided on the mounting surface. Signal terminal 31V is used for inputting and outputting vertically polarized antenna signals, and signal terminal 31H is used for inputting and outputting horizontally polarized antenna signals.

[0064] A grounding pattern G1 is provided between the filter layer 82 and the wiring layer 83, and a grounding pattern G2 is provided between the wiring layer 83 and the antenna layer 81. The grounding pattern G2 is embedded in the dielectric layer 11. The grounding pattern G1 is located at the interface between the dielectric layer 11 and the dielectric layer 12. The grounding patterns G1 and G2 are connected to the grounding post 15 that penetrates the dielectric layer 11.

[0065] Filter circuits 19V and 19H are provided in filter layer 82. Filter circuits 19V and 19H are bandpass filters and are connected to signal terminals 31V and 31H, respectively. In a top view viewed from the stack-up direction, filter circuits 19V and 19H are surrounded by multiple grounding posts 18. Grounding posts 18 are columnar conductors extending in the z-direction through the dielectric layer 12 and connected to the grounding pattern G1.

[0066] In wiring layer 83, power supply patterns 16V and 16H are provided. One end of power supply patterns 16V and 16H is connected to filter circuits 19V and 19H, respectively, and the other end of power supply patterns 16V and 16H is connected to different planar positions of antenna element 14 via power supply posts 17V and 17H, respectively. In the top view viewed from the stack-up direction, power supply patterns 16V and 16H are surrounded by multiple grounding posts 15.

[0067] With this structure, the antenna element 14 functions as a patch conductor for a dielectric antenna. Furthermore, since each antenna element 14 is surrounded by multiple grounding posts 15, mutual interference between the antenna elements 14 can be suppressed.

[0068] Figure 7 This is a circuit diagram of antenna element 10, showing the portion associated with one antenna element 14.

[0069] like Figure 7As shown, antenna signals SV and SH, supplied by signal terminals 31V and 31H respectively, are supplied to antenna element 14 via filter circuits 19V and 19H respectively. The power supply positions of antenna signals SV and SH relative to antenna element 14 are 90° apart. Thus, antenna signals SV and SH radiate from antenna element 14 into space.

[0070] Here, the upper surface of the antenna element 10 is approximately at the same height as the upper surface 21 of the metal member 20. The upper surface of the antenna element 10 is defined by the front end position of the grounding post 15 in the z-direction and is located on the second surface opposite to the mounting surface of the antenna component 3 of the grounding post 15 relative to the circuit substrate 2, with a height position of H1. The upper surface 21 of the metal member 20 is the first surface located on the opposite side of the mounting surface of the metal member 20 relative to the circuit substrate 2. When an annular pattern 13 is provided to connect the front ends of the plurality of grounding posts 15 to each other, the surface of the annular pattern 13 constitutes the upper surface of the antenna element 10. For the antenna element 14, it may also be provided at the height position H1, or as shown in the figure. Figure 6 As shown, it is set at a position slightly lower than the height position H1.

[0071] Furthermore, in this embodiment, a metal member 20 is provided to surround the antenna component 3 composed of multiple antenna elements 10, and the height position H2 of its upper surface 21 is approximately equal to the height position H1 of the antenna elements 10. Therefore, the radiation characteristics of the outermost antenna element 14 are improved. That is, without such a metal member 20, the antenna element 14 located in the central part is surrounded by other antenna elements 14. In contrast, the outermost antenna element 14 has a portion that is not adjacent to other antenna elements 14, so its radiation characteristics are different from those of the antenna element 14 located in the central part. However, in this embodiment, since the antenna component composed of multiple antenna elements 10 is surrounded by the metal member 20, the metal member 20 functions in the same way as a virtual antenna element. As a result, the characteristic difference between the multiple antenna elements 14 is reduced.

[0072] Here, the height positions H1 and H2 do not need to be exactly the same. Their difference, assuming the wavelength of the electromagnetic wave radiated from the antenna element 14 is λ, is preferably less than λ / 20. This is because when the difference between height positions H1 and H2 exceeds λ / 20, the conditional difference with the centrally located antenna element 14 increases, resulting in a significant difference in radiation characteristics. Furthermore, there is no particular limitation on the magnitude relationship between height positions H1 and H2. Preferably, height positions H1 and H2 are the same, or height position H1 is higher than height position H2. In other words, it is preferable that the upper surface 21 of the metal member 20 is lower than height position H1. This is because when H1 < H2, tilting is easily generated in the radiation pattern of the xz plane (E plane), so considering tolerances, it is desirable to design it so that H1 ≥ H2.

[0073] Furthermore, the width W of the upper surface 21 of the preferred metal member 20 (refer to...) Figure 1 (b) is λ / 2 or more. This is because by setting the width W to λ / 2 or more, the metal member 20 functions in approximately the same way as the virtual antenna element. Here, regarding the width W of the metal member 20, the portion adjacent to the antenna element 14 at the end located in the x direction refers to the width in the x direction, and the portion adjacent to the antenna element 14 at the end located in the y direction refers to the width in the y direction.

[0074] Furthermore, preferably, the gap S2 between the metal member 20 and the antenna element 10 is greater than or equal to the gap S1 between adjacent antenna elements 10 and less than λ / 2. This is because if the gap S2 is too narrow or too wide, the radiation characteristics of the outermost antenna element 14 will be different from those of the other antenna elements 14.

[0075] Furthermore, when a cavity 22 is provided inside the metal component 20, a cross-sectional view as shown in the schematic diagram can also be used. Figure 8 As shown, electronic components 40, such as semiconductor chips, are housed within the cavity 22. This allows for more efficient utilization of the surface of the circuit substrate 2, and enables the metal component 20 to function as a shielding case for electromagnetic waves from the electronic components 40. The terminal electrodes 41 of the electronic components 40 are connected to conductor patterns 43 provided on or inside the surface of the circuit substrate 2 via pad patterns 42 provided on the surface of the circuit substrate 2. Here, conductor patterns 43G supplying ground potential can also be connected to the metal component 20 via pad patterns 42. Thus, the metal component 20 functions as a heat sink, thereby improving the heat dissipation characteristics of the circuit substrate 2. Specifically, as... Figure 5As shown, if the metal component 20 is finned, its function as a heat sink is greatly enhanced. Of course, connecting the metal component 20 to the conductor pattern 43G is not necessary; it can also be fixed to the circuit substrate 2 simply using adhesive or the like. In this case, the heat dissipation characteristics of both the circuit substrate 2 and the antenna component 3 can also be improved by using the metal component 20.

[0076] As explained above, the antenna module 1 according to this embodiment, having a metal member 20 surrounding multiple antenna elements 14, can improve the radiation characteristics of the outermost antenna element 14 without adding virtual antenna elements. Specifically, in this embodiment, since a filter layer 82 is built into the antenna unit 10, the antenna unit 10 is thick, resulting in a high height position of the antenna element 14 relative to the circuit substrate 2. In such a case, without adding the metal member 20, the radiation characteristics of the outermost antenna element 14 would change significantly; however, according to this embodiment, by using the metal member 20, changes in radiation characteristics can be prevented. Furthermore, since the metal member 20 is composed of a single part, the number of components can be reduced.

[0077] Figure 9 This is a schematic perspective view illustrating the structure of the antenna module 1a in the first modified example.

[0078] Figure 9 The antenna module 1a shown uses four metal components 51-54 instead of metal component 20, which is similar to... Figure 1 The antenna module 1 shown is different. Other basic structures are the same. Figure 1 The antenna module 1 shown is the same; therefore, the same reference numerals are assigned to the same elements, and repeated descriptions are omitted.

[0079] like Figure 9 As shown, metal components 51 and 52 are respectively disposed on both sides of the antenna component 3 in the x direction, and metal components 53 and 54 are respectively disposed on both sides of the antenna component 3 in the y direction. In this case, the characteristics of the outermost antenna element 14 can be made to be approximately the same as those of the antenna element 14 located in the center.

[0080] like Figure 9 As illustrated in antenna module 1a, the metal components are not necessarily a single part surrounding the antenna element 3; they can also be composed of multiple parts arranged along each side of the antenna element 3. This increases the design freedom. Furthermore, it is not necessary to arrange the metal components 20 at all sides of the antenna element 3; depending on the required characteristics, they can be arranged along at least one side of the antenna element 3. As an example, it is also possible to... Figure 9The antenna module 1a shown omits a portion of the metal components 51 to 54. Furthermore, each of the metal components 51 to 54 may be further composed of multiple parts.

[0081] Figure 10 This is a schematic top view used to illustrate the structure of the antenna module 1b in the second variation.

[0082] Figure 10 The antenna module 1b shown is similar to the antenna module in that it consists of 16 antenna elements 60 arranged in an array in the xy direction. Figure 1 The antenna module 1 shown is different. Other basic structures are the same. Figure 1 The antenna module 1 shown is the same; therefore, the same reference numerals are assigned to the same elements, and repeated descriptions are omitted.

[0083] like Figure 10 As shown, the antenna element 60 includes: one antenna element 14 and a plurality of grounding posts 15 surrounding it. That is, with the use of Figure 2 The antenna element 10 described above differs from the antenna element 60 described above; each antenna element 60 is assigned one antenna element 14. For example... Figure 10 As illustrated in antenna module 1b, it is not necessary for a single antenna unit to contain multiple antenna elements.

[0084] Furthermore, the number of antenna elements 14 arranged in the x-direction is not necessarily the same as the number of antenna elements 14 arranged in the y-direction; for example, it can also be an array of 2×8.

[0085] The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments. Various modifications can be made without departing from the spirit of the present invention, and these modifications are of course included within the scope of the present invention.

[0086] The technology disclosed herein includes the following structural examples, but is not limited thereto.

[0087] The antenna module according to this disclosure includes: an antenna component comprising a plurality of antenna elements and ground conductors respectively surrounding the plurality of antenna elements; and a metal component disposed adjacent to the ground conductor surrounding the outermost antenna element among the plurality of antenna elements.

[0088] This improves the radiation characteristics of antenna elements adjacent to metal components.

[0089] Alternatively, the antenna component may have a structure in which multiple antenna elements are arranged in an array, with a metal member disposed along at least one side of the antenna component. This improves the radiation characteristics of the multiple antenna elements along the metal member.

[0090] Alternatively, the metal components can be arranged along each side of the antenna component. This improves the radiation characteristics of all the outermost antenna elements. In this case, the metal components can be composed of multiple parts arranged along each side of the antenna component, or they can be composed of a single part surrounding the antenna component. The former increases the design freedom, while the latter reduces the number of components.

[0091] Alternatively, the width of the metal component can be greater than half the wavelength of the electromagnetic wave radiated from the antenna element. This significantly improves the radiation characteristics of the antenna element adjacent to the metal component.

[0092] Alternatively, the height difference between the first surface located on the opposite side of the mounting surface of the metal component and the second surface located on the opposite side of the mounting surface of the antenna component of the ground conductor can be less than 1 / 20 of the wavelength of the electromagnetic wave radiated from the antenna element. This significantly improves the radiation characteristics of the antenna element adjacent to the metal component. In this case, the height of the first surface of the metal component can be less than or equal to the height of the second surface of the antenna component. This prevents the radiation pattern of the E-plane from tilting.

[0093] Alternatively, the antenna component can be composed of multiple antenna elements, each containing multiple antenna components. This prevents poor connections due to differences in thermal expansion coefficients and reduces the number of components. In this case, the gap between the metal component and the antenna component can be greater than the gap between the multiple antenna elements and less than half the wavelength of the electromagnetic wave radiated from the antenna element. This significantly improves the radiation characteristics of the antenna element adjacent to the metal component.

[0094] Alternatively, the metal component may have internal cavities. This allows electronic components such as semiconductor chips to be housed within the cavities.

[0095] Alternatively, the antenna component can be a dielectric antenna. This allows for a reduction in the overall size.

[0096] [Example]

[0097] (Example 1)

[0098] Prepare a circuit substrate 2 with planar dimensions of 120mm × 120mm, and arrange four antenna elements 10 in an array in the center of the substrate. The structure of the antenna element 10 is as follows: Figure 2 As shown, four antenna elements 14 are arranged in an array, and each antenna element 14 is surrounded by multiple grounding posts 15. The planar dimensions of the antenna element 10 are 10.6 mm × 10.6 mm, and the thickness is 2.2 mm. The gap S1 between the antenna elements 10 is 0.7 mm. The polarization direction of each antenna element 14 is the y-direction, the yz plane is the E-plane, and the xz plane is the H-plane.

[0099] Moreover, in Figure 1 In (b), the radiation pattern of the yz plane (E plane) was measured by exciting only the antenna element 14 at the location indicated by reference numeral A at 28 GHz. Figure 11 The results of the measurements are shown here. Figure 11 (a) shows the radiation pattern in the absence of metal component 20. Figure 11 (b) The radiation pattern is shown in the presence of the metal member 20. The thickness of the metal member 20 is the same as that of the antenna element 10, which is 2.2 mm, and the width W is 5 mm (≈λ / 2). The gap S2 between the metal member 20 and the antenna element 3 is 0.7 mm.

[0100] like Figure 11 As shown in (a), in the absence of the metal component 20, the antenna element 14 located at the corner experiences a significant drop in gain around -50°. In contrast, as... Figure 11 As shown in (b), it is confirmed that if the antenna component 3 is surrounded by the metal component 20, the drop in gain near -50° is eliminated.

[0101] (Example 2)

[0102] In the structure of Example 1, the change in the radiation pattern was measured when the thickness of the metal member 20, i.e., the height position H2 of the upper surface 21, was varied. Figure 12 The results are shown in [the image / image]. Figure 12 In the figures, reference numeral B1 indicates the radiation pattern when the height position H2 is the same as the height position H1 (i.e., the same conditions as in Example 1), reference numeral B2 indicates the radiation pattern when the height position H2 is 500 μm higher than the height position H1 (≈λ / 20), and reference numeral B3 indicates the radiation pattern when the height position H2 is 500 μm lower than the height position H1 (≈λ / 20).

[0103] like Figure 12 As shown, it is confirmed that if the difference between the height positions H1 and H2 is about 500 μm (≈λ / 20), then roughly the same characteristics can be obtained as when the height positions H1 and H2 are the same.

[0104] (Example 3)

[0105] In the structure of Example 1, the change in the radiation pattern was measured when the width W of the metal member 20 was varied. Figure 13 The results are shown. Figure 13In the figures, reference numeral C1 indicates the radiation pattern when the width W is 5 mm (≈λ / 2) (i.e., the same conditions as in Example 1), reference numeral C2 indicates the radiation pattern when the width W is 2.5 mm (≈λ / 4), reference numeral C3 indicates the radiation pattern when the width W is 10 mm (≈λ), and reference numeral C4 indicates the radiation pattern when the metal component 20 is absent.

[0106] like Figure 13 As shown, it is confirmed that the larger the width W of the metal component 20, the better the properties can be obtained. The properties when the width W of the metal component 20 is λ are not significantly different from those when the width W of the metal component 20 is λ / 2. If the width W is greater than λ / 2, sufficient effect can be obtained.

Claims

1. An antenna module, wherein provided are: an antenna member including a plurality of antenna elements and a ground conductor surrounding each of the plurality of antenna elements; and a metal member disposed in abutment with the ground conductor surrounding an outermost one of the plurality of antenna elements, a difference between a height position of a first surface on an opposite side of a mounting surface of the metal member and a height position of a second surface on an opposite side of the mounting surface of the ground conductor surrounding the antenna member is 1 / 20 or less of a wavelength of electromagnetic waves radiated from the antenna elements, and the height position of the first surface of the metal member is equal to or lower than the height position of the second surface of the ground conductor.

2. The antenna module according to claim 1, wherein the antenna member has a structure in which the plurality of antenna elements are arranged in an array, the metal member is disposed along at least one side of the antenna member.

3. The antenna module according to claim 2, wherein the metal member is disposed along each side of the antenna member.

4. The antenna module according to claim 3, wherein the metal member is composed of a plurality of parts disposed along each side of the antenna member, respectively.

5. The antenna module according to claim 3, wherein the metal member is composed of a single part surrounding the antenna member.

6. The antenna module according to claim 1, wherein a width of the metal member is 1 / 2 or more of the wavelength of the electromagnetic waves radiated from the antenna elements.

7. The antenna module according to claim 1, wherein the height of the second surface is higher than the height of the first surface.

8. The antenna module according to claim 1, wherein the antenna member is composed of a plurality of antenna units each including a plurality of antenna elements.

9. The antenna module according to claim 8, wherein a gap between the metal member and the antenna member is equal to or more than a gap between the plurality of antenna units, and is 1 / 2 or less of the wavelength of the electromagnetic waves radiated from the antenna elements.

10. The antenna module according to claim 1, wherein the metal member has a hollow inside.

11. The antenna module according to any one of claims 1 to 10, wherein the antenna member is a dielectric antenna. ​

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