Antenna device

Abstract

This antenna device comprises: an antenna element that includes a plurality of copper foils formed within a multilayer substrate, a plurality of vias connecting the copper foils together, a first power feed point, and a second power feed point; a ground conductor that is formed by a plurality of vias and copper foils and that is provided on the opposite side to the radiation direction of the antenna element; a first power feed line that is connected to the first power feed point and feeds power to the antenna element; and a second power feed line that is connected to the second power feed point and feeds power to the antenna element. The number of vias arranged along the vertical direction in end portions in the horizontal direction is less than the number of vias arranged along the vertical direction in parts other than the end portions in the horizontal direction, such that the antenna element has a shape in which the end portions are shorter in the vertical direction than the parts other than the end portions. The first power feed point is provided in a part other than the end portions in the horizontal direction, and the second power feed point is provided in a part other than the end portions in the vertical direction.

Description

Antenna equipment

[0001] This disclosure relates to an antenna device.

[0002] In recent years, the use of the subterahertz wave band for 6G (6th generation) communication has attracted attention. In communication between terminals and access points (APs), it has become common to use both vertical and horizontal polarization.

[0003] For example, Patent Document 1 describes a vertical antenna patch using at least one cavity region formed at the edge of a multilayer circuit structure having a number of layers stacked vertically. Patent Document 1 describes that the vertical antenna patch is configured for the transmission of vertically polarized radio signals or for the transmission of horizontally polarized radio signals.

[0004] Patent No. 6814293

[0005] However, in the high-frequency band such as the subterahertz band, the antenna patch described in Patent Document 1 has limited freedom in terms of the feed point and / or antenna shape due to manufacturing constraints, making it difficult to radiate radio waves at the desired frequency.

[0006] Non-limiting embodiments of this disclosure contribute to the provision of an antenna device capable of radiating radio waves at a desired frequency.

[0007] An antenna device according to one embodiment of the present disclosure comprises a plurality of copper foils formed in a laminated substrate, a plurality of vias connecting the copper foils, an antenna element having a first feed point and a second feed point, a ground conductor formed from the plurality of vias and copper foils and provided on the side opposite to the radiation direction of the antenna element, a first feed line connected to the first feed point and supplying power to the antenna element, and a second feed line connected to the second feed point and supplying power to the antenna element, wherein the antenna element has a shape in which the end is shorter in the vertical direction than the other part, the number of vias arranged vertically at the horizontal end is less than the number of vias arranged vertically at the other part in the horizontal direction, the first feed point is provided at the other part in the horizontal direction, and the second feed point is provided at the other part in the vertical direction.

[0008] These comprehensive or specific embodiments may be implemented as systems, devices, methods, integrated circuits, computer programs, or recording media, or as any combination of systems, devices, methods, integrated circuits, computer programs, and recording media.

[0009] According to one embodiment of the present disclosure, it is possible to emit radio waves at a desired frequency.

[0010] Further advantages and effects of one embodiment of this disclosure will be made apparent from the specification and drawings. Such advantages and / or effects are provided by several embodiments and features described in the specification and drawings, but not all of them are necessarily provided in order to obtain one or more identical features.

[0011] Figures showing examples of radio wave radiation from a communication device Figures showing an example of the relationship between wavelength and antenna size Figures showing an example of the feed point of an antenna element composed of vias and copper foil Figures showing an example of the configuration of an antenna device according to the first embodiment Figures showing an example of the X-Z cross-section of antenna element 4a viewed from the positive direction of the Y axis in Figure 4 Figures showing an example of antenna element 4a viewed from the positive direction of the X axis in Figure 4 Figures showing an example of the current distribution of an antenna element when power is applied to a feed line for vertical polarization Figures showing an example of the current distribution of an antenna element when power is applied to a feed line for horizontal polarization Figures showing an example of the reflection characteristics and isolation of a port Figures showing an example of the operating gain in the X-Y plane when power is supplied to an antenna element from port 1 Figures showing an example of the operating gain in the X-Z plane when power is supplied to an antenna element from port 1 Figure 16 shows an example of the operating gain in the X-Y plane when power is supplied. Figure 16 shows an example of the operating gain in the X-Z plane when power is supplied to the antenna element from port 2. Figure 16 shows an example of the configuration of an array antenna. Figure 16 shows an example of the operating gain in the X-Z plane when power is supplied to the antenna element from port 2. Figure 16 shows an example of the configuration of an array antenna. Figure 16 shows an example of the operating gain in the X-Z plane when power is supplied to the antenna element from port 2. Figure 16 shows an example of the operating gain in the X-Y plane when power is supplied to the antenna element from port 2. Figure 16 shows an example of the operating gain in the X-Z

[0012] The embodiments of this disclosure will be described in detail below, with reference to the drawings as appropriate. However, some unnecessarily detailed explanations may be omitted. For example, detailed explanations of already well-known matters and redundant explanations of substantially identical configurations may be omitted. This is to avoid the following explanation becoming unnecessarily verbose and to facilitate understanding for those skilled in the art.

[0013] The attached drawings and the following description are provided to enable a person skilled in the art to fully understand this disclosure, and are not intended to limit the subject matter described in the claims.

[0014] In various drawings, some elements are omitted for clarity, and some elements may not be drawn to scale.

[0015] <First Embodiment> Figure 1 is a diagram showing an example of radio wave emission from the communication device 1. Figure 1 shows a transmission perspective view of the communication device 1 and an AP (Access Point) as the communication partner of the communication device 1. The communication device 1 may be, for example, a mobile terminal such as a smartphone, tablet, or laptop computer. Alternatively, the communication device 1 may be, for example, a base station such as an AP for a wireless LAN (Local Area Network).

[0016] The communication device 1 has communication modules 1a to 1d inside. The communication modules 1a to 1d are provided, for example, on each side of a rectangular substrate so that the communication device 1 can radiate radio waves in each direction.

[0017] The main beam direction of the antennas of communication modules 1a to 1d is not uniformly determined by the movement of the communication device 1. For example, the main beam direction may change depending on the position, orientation, and attitude of the communication device 1. Therefore, communication modules 1a to 1d are required to radiate radio waves in various directions.

[0018] Phased arrays are often used to control the direction of radio wave radiation. Each antenna in a phased array is connected to an RFIC (Radio Frequency Integrated Circuit). The RFIC can change the direction of the phased array beam by adjusting at least one of the phase and amplitude of each antenna. Adjusting the phase and amplitude of the antennas corresponds, for example, to adjusting the phase and amplitude of the signal supplied to the antenna when the phased array transmits a signal, and / or to adjusting the phase and amplitude of the signal received from the antenna when the phased array receives a signal.

[0019] To improve the stability of communication between the access point (AP) and the terminal, APs often radiate vertical polarization (Vertical-polarization (V-pol.) in Figure 1) and horizontal polarization (Horizontal-polarization (H-pol.) in Figure 1), as shown in Figure 1. However, polarization loss occurs when the orientation of the terminal changes, and depending on the orientation of the terminal, communication may become impossible.

[0020] Therefore, the ability of a terminal to transmit and receive both horizontal and vertical polarizations contributes to communication stability. If both horizontal and vertical polarizations can be emitted, the signal strength can be maintained even if the orientation of the terminal changes by switching polarizations, and this can also be applied to expanding communication capacity through MIMO (multiple input multiple output) using polarization.

[0021] Figure 2 shows an example of the relationship between wavelength and antenna size. Figure 2 shows an example of a patch antenna 2a with a side length of λe / 2, and an example of an antenna element 2b corresponding to the patch antenna 2a. The antenna element 2b is composed of vias 2c and copper foil 2d. Note that λe represents the effective wavelength considering the relative permittivity of the dielectric material constituting the substrate.

[0022] In frequency bands such as the sub-GHz band, the size of vias and via lands can be made sufficiently small relative to the wavelength, allowing antenna elements to be formed without manufacturing constraints. On the other hand, in the sub-terahertz band, due to manufacturing rules, it is difficult to make the feed point and / or antenna arbitrary in shape and / or position. Manufacturing rules include, for example, at least one of the manufacturing constraints on via diameter size, via pitch, and via stack size. Microstrip antennas (MSAs), in particular, which form antennas that radiate towards the edges of the substrate within a laminated substrate, are more significantly affected by manufacturing rules because the antenna elements are formed from vias and copper foil. For example, in the 150GHz band, if the length of the long side of a microstrip antenna is λe / 2, the via land diameter will be approximately λe / 10 due to manufacturing rules.

[0023] Thus, in high-frequency bands such as the subterahertz band, it is difficult to adjust the feed point to an arbitrary position or to configure the antenna in an arbitrary shape due to manufacturing rules, making it difficult to construct an antenna that resonates at a desired frequency.

[0024] Figure 3 shows examples of feed points for antenna elements composed of vias and copper foil. Figure 3 shows two examples: Example 1, which shows the position of the feed point of antenna element 3a that radiates horizontal polarization, and Example 2, which shows the position of the feed point of antenna element 3b that radiates vertical polarization.

[0025] As shown in Example 1 of Figure 3, in the antenna element 3a that radiates horizontal polarization, the length of the current path defined from the feed point can be adjusted by adjusting the position of the feed point in the direction indicated by the arrow, making it easy to adjust the resonant frequency of the antenna element. On the other hand, as shown in Example 2 of Figure 3, in the antenna element 3b that radiates vertical polarization, the via height is a discrete value, so the feed point can only be set to one of the three locations in the direction of the arrow, making it difficult to adjust the resonant frequency of the antenna element.

[0026] Therefore, this embodiment provides an antenna device that includes an antenna element formed within a laminated substrate, having a cross-shaped and grid configuration, and corresponding to both vertical and horizontal polarization. The antenna device in this embodiment enables radiation toward the substrate edge direction of the laminated substrate.

[0027] Figure 4 shows an example of the configuration of an antenna device according to the first embodiment. Figure 4 shows an example of an antenna device 4 having an antenna element 4a and a ground conductor 4b. Figure 4 also shows the X-axis, Y-axis, and Z-axis defined for the antenna device 4. As shown in Figure 4, the angles in three-dimensional space defined by the X-axis, Y-axis, and Z-axis are represented by the angle φ made with respect to the X-axis and the angle θ made with respect to the Z-axis in the X-Y plane. For example, θ = 90 degrees and φ = 0 degrees correspond to the front direction of the antenna device 4.

[0028] The antenna device 4 is included in the stacked substrate 40. The Z-axis direction in FIG. 4 corresponds to the stacking direction of the stacked substrate 40 including the antenna device 4. The ground conductor 4b included in the stacked substrate 40 is formed by the copper foil layer 41 and the via 42. The copper foil layer 41 is formed along the X-Y plane. In the example of FIG. 4, ten layers of copper foil layers 41 are stacked. A plurality of vias 42 are formed between the copper foil layers 41. The via 42 connects between the copper foil layers 41. The positive direction of the X-axis corresponds to the main direction of the electromagnetic wave radiated by the antenna element 4a.

[0029] The Y-axis direction may be referred to as the horizontal direction, and the Z-axis direction may be referred to as the stacking direction or the vertical direction. Further, hereinafter, the side in the positive direction of the Z-axis may be referred to as "up" or "upper side", and the side in the negative direction of the Z-axis may be referred to as "down" or "lower side". Further, hereinafter, the side in the positive direction of the Y-axis may be referred to as "right" or "right side", and the side in the negative direction of the Y-axis may be referred to as "left" or "left side". Further, hereinafter, the side in the positive direction of the X-axis may be referred to as "front" or "front side", and the side in the negative direction of the X-axis may be referred to as "back" or "back side".

[0030] The antenna device 4 is connected to an RFIC or the like. The RFIC adjusts the amplitude and / or the phase of the antenna element 4a of the antenna device 4. Note that the adjustment of the amplitude and / or the phase of the antenna element 4a may be described as the adjustment of the amplitude and / or the phase of the signal supplied to the antenna element 4a. Further, the signal supplied to the antenna element 4a may be replaced with any one of the power supplied to the antenna element 4a, the current supplied to the antenna element 4a, and the voltage applied to the antenna element 4a.

[0031] FIG. 5 is a diagram showing an example of the X-Z cross section of the antenna element 4a viewed from the positive direction of the Y-axis in FIG. 4. FIG. 6 is a diagram showing an example of the antenna element 4a viewed from the positive direction of the X-axis in FIG. 4. Hereinafter, description will be made with reference to FIGS. 4 to 6.

[0032] The antenna element 4a has a structure that is symmetric up and down and symmetric left and right.

[0033] The antenna element 4a includes copper foil layers 11 to 15, vias 21 and 22 connecting the copper foil layer 11 and the copper foil layer 12, vias 23 to 26 connecting the copper foil layer 12 and the copper foil layer 13, vias 27 to 30 connecting the copper foil layer 13 and the copper foil layer 14, and vias 31 and 32 connecting the copper foil layer 14 and the copper foil layer 15. Each copper foil layer includes via lands.

[0034] In the antenna element 4a, the vias are arranged in a plurality of stages via the copper foil layers. When the plurality of stages are described as the first stage, the second stage, the third stage, and the fourth stage in order from the top, in the antenna element 4a, two vias are arranged in the first stage, four vias are arranged in each of the second stage and the third stage, and two vias are arranged in the fourth stage.

[0035] Also, the antenna element 4a has a plurality of columns of vias arranged along the Z axis. When the plurality of columns of vias are described as the first column, the second column, the third column, and the fourth column in order from the left, in the antenna element 4a, two vias are arranged in the first column, four vias are arranged in each of the second column and the third column, and two vias are arranged in the fourth column.

[0036] As described above, the antenna element 4a has a cross shape by arranging vias in a plurality of stages and a plurality of columns.

[0037] In the antenna element 4a, there are a central portion and an end portion in the horizontal direction (Y-axis direction), and the central portion in the horizontal direction is longer in the vertical direction than the end portion in the horizontal direction. Here, the central portion of the antenna element 4a in the horizontal direction is the second column and the third column, and the end portions of the antenna element 4a in the horizontal direction are the first column and the fourth column. That is, in the antenna element 4a, the second column and the third column are longer in the vertical direction (Z-axis direction) than the first column and the fourth column. Note that the fact that the second column and the third column are longer in the vertical direction than the first column and the fourth column corresponds to the number of vias arranged vertically in the second column and the third column being larger than that in the first column and the fourth column.

[0038] Furthermore, the antenna element 4a has a central part and an end part in the vertical direction, and the central part in the vertical direction is longer horizontally than the end part in the vertical direction. Here, the central part of the antenna element 4a in the vertical direction is the second and third stages, and the end part of the antenna element 4a in the vertical direction is the first and fourth stages. In other words, in the antenna element 4a, the second and third stages are longer horizontally (in the Y-axis direction) than the first and fourth stages. Note that the fact that the second and third stages are longer horizontally than the first and fourth stages means that the number of vias arranged horizontally in the second and third stages is greater than that in the first and fourth stages.

[0039] As described above, due to the difference in length between the central part and the ends, the antenna element 4a has a cross-shaped grid structure.

[0040] A grounding conductor 4b is positioned in the direction opposite to the radiation direction (positive direction of the X-axis) of the antenna element 4a (negative direction of the X-axis). The antenna element 4a has a feed point Pv for vertical polarization and a feed point Ph for horizontal polarization. A feed line 4c is connected to feed point Pv, and a feed line 4d is connected to feed point Ph. Feed lines 4c and 4d are connected to an RFIC or the like.

[0041] As shown in Figure 5, when the antenna element 4a is fed from the feed point Pv, an electric field 5a is generated between the antenna element 4a and the ground conductor 4b. The antenna element 4a then radiates a vertically polarized wave with the main electric field direction in the Z-axis direction toward the positive X-axis direction.

[0042] Similar to vertical polarization, when the antenna element 4a is fed from the feed point Ph, an electric field is generated between the antenna element 4a and the ground conductor 4b for horizontal polarization. The antenna element 4a then radiates horizontal polarization with the main electric field direction in the Y-axis direction in the positive X-axis direction.

[0043] The resonant frequencies for vertical and horizontal polarization are controlled by adjusting the length of at least one of the copper foil layers 11-15 of the antenna element 4a and the arrangement of at least one of the vias 21-32. The resonant frequencies for vertical and horizontal polarization are determined based on the current path through which current flows when each polarization is radiated.

[0044] The current path in the antenna element 4a when each of vertical polarization and horizontal polarization is radiated will be described with reference to FIG. 6.

[0045] In the case of vertical polarization, in the antenna element 4a fed from the feeding point Pv, a current path J Ｖ is generated. The current flows along the current path J Ｖ The current path J Ｖ includes a path starting from the feeding point Pv and passing through the copper foil layer 11, via vias 21, 24, 28, and via 31, and a path starting from the feeding point Pv and passing through the copper foil layer 11, via vias 22, 25, 29, and via 32. In vertical polarization, the resonance frequency is determined by the electrical length l Ｖ Note that the electrical length l Ｖ represents the electrical length of the current path. For example, the electrical length l Ｖ represents the electrical length determined based on the length of the current path and the dielectric constant of the dielectric.

[0046] In the case of horizontal polarization, in the antenna element 4a fed from the feeding point Ph, a current path J Ｈ is generated. The current flows along the current path J Ｈ The current path J Ｈ includes a path starting from the feeding point Ph and passing through via 26 and the copper foil layer 12, and a path starting from the feeding point Ph and passing through via 30 and the copper foil layer 13. In horizontal polarization, the resonance frequency is determined by the electrical length l Ｈ Note that the electrical length l

[0047] By adjusting the length La and / or Lb of the copper foil layer of the antenna element 4a, the electrical length is adjusted. Exemplarily, by adjusting La, the electrical length l Ｖ is adjusted. Also, by adjusting Lb, the electrical length l Ｈ is adjusted. In the antenna element 4a, La and Lb can be adjusted independently. For example, without changing the length of Lb, the length of La can be increased or decreased. Thereby, the resonance frequency of vertical polarization and the resonance frequency of horizontal polarization can be adjusted individually.

[0048] The length of La may be adjusted by changing the length of the copper foil layer 11 or by changing the arrangement of the vias. Similarly, the length of Lb may be adjusted by changing the lengths of the copper foil layer 12 and the copper foil layer 14 or by changing the arrangement of the vias.

[0049] Resonant frequency f of vertical polarization Ｖ This is determined by equation (1). Also, the resonant frequency f of horizontal polarization is Ｈ This is determined by equation (2). In equations (1) and (2), c represents the speed of light, and ε ｅ This represents the effective relative permittivity.

[0050] <Characteristic Comparison> Next, the characteristics of the antenna device 4 shown in Figures 4 to 6 are shown. First, the current distribution when power is applied to the antenna element 4a of the antenna device 4 from the feed line is shown.

[0051] Figure 7 shows an example of the current distribution of the antenna element 4a when power is applied to the feed line 4c for vertical polarization. Figure 7 illustrates the current distribution of the antenna element 4a when power is applied to the feed line 4c of the antenna device 4 shown in Figures 4 to 6. Note that Figure 7 shows the same X, Y, and Z axes as in Figures 4 to 6.

[0052] In the example in Figure 7, the current path J is mainly in the vertical direction (Z-axis direction) of the antenna element 4a. Ｖ As the current flows along (see Figure 6), vertical polarization is radiated. Also, as shown in Figure 7, when power is applied to the power supply line 4c, the current flowing through the power supply line 4d is small.

[0053] Figure 8 shows an example of the current distribution of the antenna element 4a when power is applied to the feed line 4d for horizontal polarization. Figure 8 illustrates the current distribution of the antenna element 4a when power is applied to the feed line 4d of the antenna device 4 shown in Figures 4 to 6. Note that Figure 8 shows the same X, Y, and Z axes as in Figures 4 to 6.

[0054] In the example shown in Figure 8, the current path J is mainly in the horizontal direction (Y-axis direction) of the antenna element 4a. Ｈ(See Figure 6) Because current flows, horizontal polarization is radiated. Also, as shown in Figure 8, when power is applied to the power line 4d, the current flowing through the power line 4c is small.

[0055] Next, the reflection characteristics and isolation of antenna element 4a are shown.

[0056] Figure 9 shows an example of port reflection characteristics and isolation. The horizontal axis in Figure 9 represents the frequency axis, and the vertical axis represents the magnitude of the S-parameter. Figure 9 shows the S-parameter as the frequency changes. １１ S ２１ , and S ２２ The respective sizes are shown. In the example in Figure 9, the horizontal polarization feed line 4d that supplies power to the antenna element 4a corresponds to port 1, and the vertical polarization feed line 4c corresponds to port 2. In the example in Figure 9, the center frequency of the desired frequency band is set to 157.75 GHz, but structurally, the resonant frequencies of vertical polarization and horizontal polarization may differ.

[0057] S １１ S corresponds to the frequency with the smallest magnitude. １１ The resonant frequency is approximately 151.5 GHz. ２２ S corresponds to the frequency with the smallest magnitude. ２２ The resonant frequency is approximately 164 GHz. Figure 9 shows a level of -10 dB or less at the desired frequency band of 157.75 GHz.

[0058] Furthermore, S indicates isolation between port 1 and port 2. ２１ However, since it shows approximately -15 dB around the desired frequency band, it indicates low coupling between ports. ２１ This indicates the degree to which power leaks from one of the feed lines—the horizontal polarization feed line or the vertical polarization feed line—to the other.

[0059] Also, S １１ The bandwidth of port 1 where the noise level is below -10 dB is from 141 GHz to 179 GHz, and the relative bandwidth is 24.1%. ２２ The bandwidth of port 2 where the noise level is below -10 dB is from 150 GHz to 187 GHz, and the relative bandwidth is 23.4%.

[0060] Figure 10 shows an example of the operating gain in the X-Y plane when power is supplied from port 1 to antenna element 4a. Figure 11 shows an example of the operating gain in the X-Z plane when power is supplied from port 1 to antenna element 4a. In Figures 10 and 11, the horizontal axis represents angle, and the vertical axis represents gain. The angle on the horizontal axis is expressed in degrees. The angle "Phi" on the horizontal axis in Figure 10 corresponds to "φ" shown in Figure 4, and the angle "Theta" on the horizontal axis in Figure 11 corresponds to "θ" shown in Figure 4. In Figures 10 and 11, the gains are shown exemplarily when one antenna element 4a (for example, an antenna element 4a having one desired frequency) is excited at three different frequencies: 151.5 GHz, 157.75 GHz, and 164 GHz. In Figures 10 and 11, the solid line represents the gain of the primary polarization, and the dashed line represents the gain of the cross-polarization.

[0061] As shown in Figures 10 and 11, the operating gain in the front direction (Theta = 90 degrees, Phi = 0 degrees) is approximately 8 dBi in both the X-Y and X-Z planes. Furthermore, this operating gain is similar in magnitude for each of the three frequencies. The cross-polarization discrimination (XPD) is approximately 15 dB.

[0062] Figure 12 shows an example of the operating gain in the X-Y plane when power is supplied from port 2 to antenna element 4a. Figure 13 shows an example of the operating gain in the X-Z plane when power is supplied from port 2 to antenna element 4a. In Figures 12 and 13, the horizontal axis represents angle, and the vertical axis represents gain. The angle on the horizontal axis is expressed in degrees. The angle "Phi" on the horizontal axis in Figure 12 corresponds to "φ" shown in Figure 4, and the angle "Theta" on the horizontal axis in Figure 13 corresponds to "θ" shown in Figure 4. Figures 10 and 11 show the gain for three different frequencies: 151.5 GHz, 157.75 GHz, and 164 GHz, as an example. In Figures 12 and 13, the solid line shows the gain of the primary polarization, and the dashed line shows the gain of the cross-polarization.

[0063] As shown in Figures 12 and 13, the operating gain in the front direction (Theta = 90 degrees, Phi = 0 degrees) is approximately 8 dBi in both the X-Y and X-Z planes. Furthermore, this operating gain is similar for each of the three frequencies. The cross-polarization discrimination is 20 dB.

[0064] <Example of Array Configuration> The configuration of the antenna device 4 shown in Figures 4 to 6 may be extended to an array antenna by arranging multiple antenna elements 4a.

[0065] Figure 14 shows an example of an array antenna configuration. Figure 14 shows an example of an antenna device 110 in which antenna elements 4a-1 and 4a-2 are arranged along the Y-axis at the edge of a substrate. The distance between adjacent antenna elements 4a-1 and 4a-2 is λ ０ It is / 2. Furthermore, λ ０ This corresponds to the free-space wavelength of the radio waves emitted by the antenna device 110.

[0066] In the antenna device 110 shown in Figure 14, antenna elements 4a-1 and 4a-2 located at the negative end of the Y-axis are dummy antenna elements, and antenna elements 4a-1 and 4a-2 located at the positive end of the Y-axis are also dummy antenna elements.

[0067] Antenna element 4a-1 has the same configuration as antenna element 4a shown in Figure 4. That is, the arrangement of vias and copper foil layers of antenna element 4a-1 is the same as that of antenna element 4a shown in Figure 4. Also, the position of the feed point of antenna element 4a-1 is the same as that of antenna element 4a shown in Figure 4. A feed point Pv is provided on the positive Z-axis side of antenna element 4a-1, and a feed point Ph is provided on the positive Y-axis side.

[0068] The via arrangement and copper foil layer arrangement of antenna element 4a-2 are the same as those of antenna element 4a shown in Figure 4. The position of the feed point of antenna element 4a-2 is different from that of antenna element 4a shown in Figure 4. The feed point Pv is provided on the positive Z-axis side of antenna element 4a-2, and the feed point Ph is provided on the negative Y-axis side.

[0069] In this configuration, antenna elements 4a-1 and 4a-2 have a mirror-image inversion relationship with each other. Because adjacent antenna elements 4a-1 and 4a-2 are mirror images of each other, coupling between antenna elements can be suppressed.

[0070] Figure 14 shows an example in which multiple antenna elements are arranged along the Y-axis, but the disclosure is not limited to this. For example, multiple antenna elements may be arranged planarly along both the Y-axis and Z-axis. Even when antenna elements are arranged planarly, there may be a mirror-image reversal relationship between adjacent antenna elements. Referring to Figure 14, in Figure 14, if an additional row of antenna elements is arranged on the positive Z-axis side, then an antenna element is arranged on the positive Z-axis side of antenna element 4a-1 such that the feed point Pv of antenna element 4a-1 is located on the negative Z-axis side, and an antenna element is arranged on the positive Z-axis side of antenna element 4a-2 such that the feed point Pv of antenna element 4a-2 is located on the negative Z-axis side. With such an arrangement, coupling between antenna elements can be suppressed even when antenna elements are arranged planarly.

[0071] However, as illustrated in Figure 14, this disclosure does not require adjacent antenna elements to have a mirror-image reversal relationship. By having adjacent antenna elements with the same configuration but without a mirror-image reversal relationship, wiring can be simplified.

[0072] <Variations in Antenna Element Configuration> In the antenna device 4 shown in Figures 4 to 6, if we describe the layers of vias stacked in the Z-axis direction up to four times in the antenna element 4a as the 1st layer, 2nd layer, 3rd layer, and 4th layer from top to bottom, then two vias are placed in the 1st layer, four vias are placed in the 2nd and 3rd layers each, and two vias are placed in the 4th layer. Also, in the antenna element 4a, if we describe the rows of vias arranged in four columns in the Y-axis direction from left to right as the 1st column, 2nd column, 3rd column, and 4th column, then two vias are placed in the 1st column, four vias are placed in the 2nd and 3rd columns each, and two vias are placed in the 4th column.

[0073] The configuration of the antenna element in this disclosure is not limited to the example of antenna element 4a shown in Figures 4 to 6. Here, variations in the configuration of the antenna element are described. The following variations in the configuration of the antenna element are described using diagrams of the Y-Z plane when the antenna element is viewed from the positive direction of the X axis, similar to Figure 6. The following diagrams of variations in the configuration of the antenna element show examples of antenna elements composed of copper foil layers and vias, similar to Figure 6, and show the same X, Y, and Z axes as in Figure 6, as well as the feed point Pv for vertical polarization and the feed point Ph for horizontal polarization of each antenna element.

[0074] Figure 15A shows a first example of a variation in the configuration of the antenna element. The via arrangement in the antenna element 41a shown in Figure 15A is the same as that of the antenna element 4a shown in Figure 4, etc., but in the antenna element 41a, the copper foil layer between the second via and the third via is not connected in the Y-axis direction.

[0075] Because the copper foil layer between the second and third vias is not connected in the Y-axis direction, a current path is not formed that passes through this copper foil layer starting from the feed point Ph. Therefore, the horizontal polarization bandwidth of the antenna element 41a can be narrowed.

[0076] Figure 15B shows a second example of a variation in the configuration of the antenna element. In the antenna element 42a shown in Figure 15B, if we refer to the stages from top to bottom as 1st to 6th stages, there are two vias in the 1st and 2nd stages, six vias in the 3rd and 4th stages, and two vias in the 5th and 6th stages. Also, in the antenna element 42a, if we refer to the columns from left to right as 1st to 6th columns, there are two vias in the 1st and 2nd columns, six vias in the 3rd and 4th columns, and two vias in the 5th and 6th columns. Furthermore, the copper foil layer between the vias of the 3rd stage and the vias of the 4th stage is not connected in the Y-axis direction.

[0077] The antenna element 42a shown in Figure 15B has a configuration that is extended in both the Z and Y axes compared to the antenna element 41a shown in Figure 15A. This configuration allows the antenna element 42a to form a longer current path than the antenna element 41a, thus enabling the frequency to be adjusted to a lower frequency range.

[0078] Figure 15C shows a third example of a variation in the configuration of the antenna element. In the antenna element 43a shown in Figure 15C, if we refer to them from top to bottom as the 1st stage, 2nd stage, 3rd stage, and 4th stage, one via is placed in the 1st stage, three vias are placed in the 2nd and 3rd stages, and one via is placed in the 4th stage. Also, in the antenna element 43a, if we refer to them from left to right as the 1st column, 2nd column, and 3rd column, two vias are placed in the 1st column, four vias are placed in the 2nd column, and two vias are placed in the 3rd column.

[0079] The antenna element 43a shown in Figure 15C has a reduced configuration in both the Z and Y axes compared to the antenna element 4a shown in Figures 4 to 6. This configuration allows for the formation of a shorter current path in antenna element 43a than in antenna element 4a, thus enabling adjustment of the resonant frequency to a higher frequency.

[0080] Figure 15D shows a fourth example of a variation in the configuration of the antenna element. In the antenna element 44a shown in Figure 15D, if we refer to them from top to bottom as the first stage, second stage, etc., one via is placed in the first stage and one via is placed in the second stage. In addition, the antenna element 44a has a row of vias arranged along the Y axis.

[0081] The antenna element 44a shown in Figure 15D has a reduced configuration in both the Z and Y axes compared to the antenna element 43a shown in Figure 15C. This configuration allows for the formation of a shorter current path in antenna element 44a than in antenna element 43a, thus enabling adjustment of the resonant frequency to a higher frequency range.

[0082] Although the antenna elements 4a and 41a to 44a described above have a vertically symmetrical and horizontally symmetrical configuration, this disclosure is not limited thereto. Examples of antenna elements that do not have symmetry will be described below.

[0083] Figure 15E shows a fifth example of a variation in the configuration of the antenna element. In the antenna element 45a shown in Figure 15E, if we refer to the rows from top to bottom as 1st to 6th, there are two vias in each of the 1st to 3rd rows, six vias in each of the 4th and 5th rows, and two vias in the 6th row. Also, in the antenna element 45a, if we refer to the columns from left to right as 1st to 6th, there are two vias in each of the 1st to 3rd columns, six vias in each of the 4th and 5th columns, and two vias in the 6th column.

[0084] The antenna element 45a shown in Figure 15E has the same number of stages, columns, and vias as the antenna element 42a shown in Figure 15B. While the antenna element 42a shown in Figure 15B is vertically symmetrical and horizontally symmetrical, the antenna element 45a shown in Figure 15E is neither vertically symmetrical nor horizontally symmetrical. However, the antenna element 45a has a cross shape. Since the antenna element 45a shown in Figure 15E forms a current path similar to that of the antenna element 42a shown in Figure 15B, it can radiate vertically and horizontally polarized waves with the same resonant frequencies as the antenna element 42a.

[0085] Figure 15F shows a sixth example of a variation in the configuration of the antenna element. In the antenna element 46a shown in Figure 15F, if we refer to the rows from top to bottom as 1st to 6th, there are two vias in each of the 1st to 4th rows, and six vias in each of the 5th and 6th rows. Also, in the antenna element 46a, if we refer to the columns from left to right as 1st to 6th, there are two vias in each of the 1st and 2nd columns, six vias in each of the 3rd and 4th columns, and two vias in each of the 5th and 6th columns.

[0086] The antenna element 46a shown in Figure 15F has the same number of stages, columns, and vias as the antenna element 42a shown in Figure 15B. While the antenna element 42a shown in Figure 15B is vertically and horizontally symmetrical, the antenna element 46a shown in Figure 15F is horizontally symmetrical but not vertically symmetrical. Furthermore, the antenna element 46a shown in Figure 15F has a T-shape. Since the antenna element 46a shown in Figure 15F forms a current path similar to that of the antenna element 42a shown in Figure 15B, it can radiate vertically and horizontally polarized waves with the same resonant frequencies as the antenna element 42a.

[0087] Figure 15G shows a seventh example of the variation in the configuration of the antenna element. In the antenna element 47a shown in Figure 15G, if we refer to the stages from top to bottom as 1st to 6th stages, two vias are placed in each of the 1st to 4th stages, and six vias are placed in each of the 5th and 6th stages. Also, in the antenna element 47a, if we refer to the columns from left to right as 1st to 6th columns, two vias are placed in each of the 1st to 4th columns, and six vias are placed in each of the 5th and 6th columns.

[0088] The antenna element 47a shown in Figure 15G has the same number of stages, columns, and vias as the antenna element 42a shown in Figure 15B. While the antenna element 42a shown in Figure 15B is vertically symmetrical and horizontally symmetrical, the antenna element 47a shown in Figure 15G is neither horizontally symmetrical nor vertically symmetrical. Furthermore, the antenna element 47a shown in Figure 15G has an L-shape. Since the antenna element 47a shown in Figure 15G forms a current path similar to that of the antenna element 42a shown in Figure 15B, it can radiate vertically and horizontally polarized waves with the same resonant frequencies as the antenna element 42a.

[0089] The feed point locations shown for each antenna element described above are examples only, and this disclosure is not limited thereto. The feed point Pv for vertical polarization may be determined based on the relationship between the desired resonant frequency of vertical polarization and the configuration of the antenna element (e.g., the number of vias, the position of the vias, the size of the vias, the length of the copper foil layer). Similarly, the feed point Ph for horizontal polarization may be determined based on the relationship between the desired resonant frequency of horizontal polarization and the configuration of the antenna element (the number of vias, the position of the vias, the size of the vias, the length of the copper foil layer). For example, the feed point location may be determined such that the electrical length defined by the feed point location and the configuration of the antenna element becomes the electrical length that achieves the desired resonant frequency.

[0090] Figure 15H shows examples of variations in the position of the feed point. Figure 15H shows the range in which feed points Pv and Ph can be provided for the antenna element 4a shown in Figure 6. The position of the feed point of the antenna element 4a is not limited to the example shown in Figure 6, and the position of the feed point may be set within the range shown in Figure 15H.

[0091] <Summary of the First Embodiment> As described above, the antenna device 4 has an antenna element 4a formed in a laminated substrate and a ground conductor 4b. The antenna element 4a has a cross shape and a grid configuration and is formed by a plurality of copper foil layers, vias, and via lands. The ground conductor 4b is arranged on the opposite side of the radiation direction of the antenna element 4a and is formed by a plurality of copper foil layers, vias, and via lands. The antenna element 4a has a feed point for vertical polarization and a feed point for horizontal polarization. This makes it possible to radiate radio waves with vertical and horizontal polarization towards the edge of the substrate.

[0092] Furthermore, in a terminal equipped with the antenna device according to this embodiment, stable communication becomes possible regardless of the orientation of the terminal, and an improvement in communication capacity due to polarized MIMO can be expected. In addition, even under manufacturing constraints, resonance at a desired frequency can be achieved by adjusting the effective length of the current path.

[0093] Furthermore, it has two feed points, one for vertical polarization and one for horizontal polarization, and the resonant frequency of each polarization can be controlled by adjusting the length of the copper foil layer and the arrangement of the vias. In addition, by positioning the two feed points, one for vertical polarization and one for horizontal polarization, appropriately in the cross shape, the influence of one feed point on the other can be reduced, and the isolation characteristics can be improved.

[0094] <Second Embodiment> In the second embodiment, a laminated substrate (multilayer substrate) is used as the substrate, similar to the first embodiment, but the configuration of the surface and back layers of the laminated substrate in the second embodiment differs from that of the first embodiment.

[0095] Figure 16 shows an example of the configuration of an antenna device 7 according to a second embodiment. Figure 16 shows an example of an antenna device 7 having an antenna element 43a and a ground conductor 7b. The antenna element 43a is the same as in the example shown in Figure 15C. Figure 16 also shows the X, Y, and Z axes defined for the antenna device 7. The relationship between the X, Y, and Z axes is the same as in the example shown in Figure 4.

[0096] The antenna device 7 is included in the laminated substrate 70. The Z-axis direction in Figure 16 corresponds to the stacking direction of the laminated substrate 70 including the antenna device 7. The ground conductor 7b included in the laminated substrate 70 is formed by copper foil layers and vias. The copper foil layers are formed along the X-Y plane. Multiple vias are formed between the copper foil layers. The vias connect the copper foil layers. The positive direction of the X axis corresponds to the main direction of electromagnetic waves radiated by the antenna element 43a.

[0097] The antenna element 43a has a feed point Pv for vertical polarization and a feed point Ph for horizontal polarization. A feed line 7c is connected to feed point Pv, and a feed line 7d is connected to feed point Ph. Feed lines 7c and 7d are connected to an RFIC or the like.

[0098] Figure 17 is a view of the X-Z plane passing through the feed point Pv of the antenna device 7 shown in Figure 16, as seen from the positive direction of the Y axis. The following explanation will refer to Figures 16 and 17.

[0099] In the laminated substrate on which the antenna device 7 is formed, the dielectric material constituting the upper surface dielectric layer 71 is different from the dielectric material constituting the inner dielectric layer 72. Also, the dielectric material constituting the lower surface (also called the back layer) dielectric layer 73 is different from the dielectric material constituting the inner dielectric layer 72. For example, the surface dielectric layer 71 and dielectric layer 73 may be made of a material with greater strength than the inner dielectric layer 72. By using a stronger material for the surface layer, damage to the mounting surface can be prevented when mounting an RFIC on the laminated substrate 70 including the antenna device 7.

[0100] Furthermore, of the multiple copper foil layers constituting the ground conductor 7b, copper foil layer 74 and copper foil layer 75 extend in the positive X-axis direction to a position where the antenna element 43a is hidden when viewed from the positive Z-axis direction and the negative Z-axis direction. In other words, the end of copper foil layer 74 in the positive X-axis direction is located in front of the antenna element 43a, and the end of copper foil layer 75 in the positive X-axis direction is located in front of the antenna element 43a. In other words, copper foil layer 74 and copper foil layer 75 are formed in such a way that they provide an overhang over the antenna element 43a. Note that copper foil layer 74 and copper foil layer 75 may each be provided with a notch W.

[0101] Furthermore, the ground conductor 7b includes a side wall 76 and a side wall 77. The side wall 76 extends in the positive direction of the X-axis to a position where the antenna element 43a is hidden when viewed from the negative direction of the Y-axis. The side wall 77 extends in the positive direction of the X-axis to a position where the antenna element 43a is hidden when viewed from the positive direction of the Y-axis. In other words, the end of the side wall 76 in the positive direction of the X-axis is located in front of the antenna element 43a, and the end of the side wall 77 in the positive direction of the X-axis is located in front of the antenna element 43a.

[0102] In this way, by forming the copper foil layer 74, the copper foil layer 75, the side wall 76, and the side wall 77 to surround the antenna element 43a, the influence that the antenna element 43a has on circuit elements provided around it, and / or the influence that the antenna element 43a receives from circuit elements provided around it, can be reduced. For example, when a plurality of antenna elements 43a are arranged in an array, as in the example in Figure 14, coupling between the antenna elements 43a can be suppressed by forming the copper foil layer and the side wall to surround each of the antenna elements 43a, as in the second embodiment.

[0103] Figures 16 and 17 show examples in which the copper foil layer 74, the copper foil layer 75, the side wall 76, and the side wall 77 are formed to surround the antenna element 43a, but the disclosure is not limited to this. The copper foil layers and side walls may be formed according to the positional relationship between the antenna element and other circuit elements, etc. For example, in order to reduce the influence on circuit elements located above and below the antenna element 43a, and / or the influence received from such circuit elements, the copper foil layer 74 and the copper foil layer 75 are formed between the circuit elements and the antenna element 43a, surrounding the antenna element 43a. In this case, the side walls 76 and 77 located to the left and right of the antenna element 43a do not have to be formed to surround the antenna element 43a.

[0104] While the beer land is usually circular, if a copper foil larger than the beer land is formed, the beer land may have a shape other than circular. For example, the copper foil layers 11 to 15 of the antenna element 4a shown in Figures 4 to 6 have a rounded shape in accordance with the circular shape of the beer land, but if the beer land has a shape other than circular, the copper foil layers included in the antenna element may have a shape other than rounded.

[0105] Furthermore, as described above, a long copper foil (which may be called a horizontal copper foil, for example) extending horizontally and spanning multiple vias extending vertically is placed in the central part of the antenna element 4a. The number of copper foils (or vias) in each layer increases as you get closer to the center and decreases as you get further away from the center.

[0106] <Summary of Embodiments> An antenna device according to one embodiment of the present disclosure comprises a plurality of copper foils formed in a laminated substrate, a plurality of vias connecting the copper foils, an antenna element having a first feed point and a second feed point, a ground conductor formed from the plurality of vias and copper foils and provided on the side opposite to the radiation direction of the antenna element, a first feed line connected to the first feed point and supplying power to the antenna element, and a second feed line connected to the second feed point and supplying power to the antenna element, wherein the antenna element has a shape in which the end is shorter in the vertical direction than the other part, the number of vias arranged vertically at the horizontal end is less than the number of vias arranged vertically at the other part in the horizontal direction, the first feed point is provided at the other part in the horizontal direction, and the second feed point is provided at the other part in the vertical direction.

[0107] In this antenna device, the frequency of the vertically polarized waves radiated from the antenna element is determined by the length of the current path defined along the vias and copper foil included in the portion other than the end in the horizontal direction, starting from the first feed point, and the frequency of the horizontally polarized waves radiated from the antenna element is determined by the length of the current path defined along the vias and copper foil included in the portion other than the end in the vertical direction, starting from the second feed point.

[0108] In this antenna device, a wall formed of copper foil and / or copper foil and vias is provided at a position surrounding the antenna element.

[0109] In this antenna device, there are a plurality of antenna elements, and the plurality of antenna elements are arranged at regular intervals along at least one of the horizontal and vertical directions.

[0110] In this antenna device, adjacent antenna elements have the first feed point and the second feed point at positions that are mirror images of each other.

[0111] In this antenna device, a wall formed of copper foil and / or copper foil and vias is provided between adjacent antenna elements.

[0112] The numerical values ​​such as length and angle described above may include abbreviations. For example, λg / 4 may be read as λg / 4 or abbreviated λg / 4.

[0113] While embodiments have been described above with reference to the drawings, this disclosure is not limited to such examples. It will be apparent to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims. Such modifications or alterations are understood to fall within the technical scope of this disclosure. Furthermore, the components in the embodiments may be combined in any way without departing from the spirit of this disclosure. Also, the embodiments may be combined in any way.

[0114] Each component used in the description of the above embodiments may be implemented, in part or in whole, as an integrated circuit (LSI). An LSI may consist of individual chips, or it may consist of a single chip containing some or all of the components. An LSI may have data inputs and outputs. Depending on the degree of integration, LSIs may also be referred to as ICs, system LSIs, super LSIs, or ultra LSIs.

[0115] Furthermore, if advancements in semiconductor technology or related technologies lead to the emergence of integrated circuit technologies that can replace LSIs, then naturally, these technologies can be used to integrate functional blocks. The application of biotechnology, for example, is a possibility.

[0116] This disclosure is applicable to all types of devices, systems, and equipment with communication capabilities (collectively referred to as communication equipment). Non-exclusive examples of communication equipment include telephones (mobile phones, smartphones, etc.), tablets, personal computers (PCs) (laptops, desktops, notebooks, etc.), cameras (digital still / video cameras, etc.), digital players (digital audio / video players, etc.), wearable devices (wearable cameras, smartwatches, tracking devices, etc.), game consoles, digital book readers, telehealth and telemedicine devices, vehicles or mobile transport with communication capabilities (cars, airplanes, ships, etc.), and combinations of the above-mentioned equipment.

[0117] Communication devices are not limited to portable or movable devices, but also include all kinds of non-portable or fixed devices, devices, and systems, such as smart home devices (appliances, lighting fixtures, smart meters or measuring instruments, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

[0118] Communication includes data communication via cellular systems, wireless LAN systems, and communication satellite systems, as well as data communication using combinations of these.

[0119] Furthermore, communication equipment includes infrastructure facilities such as base stations, access points, and any other devices, devices, and systems that communicate with or control the aforementioned non-limited types of equipment.

[0120] All disclosures of the U.S. provisional application 63 / 707,477, filed on 15 October 2024, are incorporated herein by reference.

[0121] One embodiment of the present disclosure is useful for an antenna device.

[0122] 4, 7, Antenna device 4a, 41a, 42a, 43a Antenna element 4b, 7b Ground conductor

Claims

1. An antenna device comprising: a plurality of copper foils formed in a laminated substrate; a plurality of vias connecting the copper foils; a first feed point; a second feed point; a ground conductor formed by the plurality of vias and copper foils and provided on the side opposite to the radiation direction of the antenna element; a first feed line connected to the first feed point and supplying power to the antenna element; and a second feed line connected to the second feed point and supplying power to the antenna element, wherein the antenna element has a shape in which the end is shorter in the vertical direction than the other part of the horizontal end, the number of vias arranged vertically at the horizontal end is less than the number of vias arranged vertically at the other part of the horizontal end; the first feed point is provided in the part other than the end in the horizontal direction; and the second feed point is provided in the part other than the end in the vertical direction.

2. The antenna device according to claim 1, wherein the frequency of the vertical polarization radiated from the antenna element is determined by the length of the current path defined along the vias and copper foil included in the portion other than the end in the horizontal direction, starting from the first feed point, and the frequency of the horizontal polarization radiated from the antenna element is determined by the length of the current path defined along the vias and copper foil included in the portion other than the end in the vertical direction, starting from the second feed point.

3. The antenna device according to claim 1, wherein a wall formed of copper foil and / or copper foil and vias is provided at a position surrounding the antenna element.

4. The antenna device according to claim 1, having a plurality of antenna elements, wherein the plurality of antenna elements are arranged at regular intervals along at least one of the horizontal and vertical directions.

5. The antenna device according to claim 4, wherein adjacent antenna elements have the first feed point and the second feed point in positions that are mirror images of each other.

6. The antenna device according to claim 5, wherein a wall formed of copper foil and / or copper foil and vias is provided between adjacent antenna elements.

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