Antenna element, antenna substrate, and antenna module

Abstract

The antenna element includes: a ground conductor; a feed patch conductor positioned above the ground conductor; and a non-feed patch conductor positioned above the feed patch conductor. The feed patch conductor has a first side and a second side in the resonance direction, the non-feed patch conductor has a plurality of segment bodies, the plurality of segment bodies include a first segment body arranged along the first side and a second segment body arranged along the second side, and in a plan view, the first segment body and the second segment body are separated from each other. The total area of the non-feed patch conductors is smaller than the area of the feed patch conductors.

Description

Technical Field

[0001] The present disclosure relates to an antenna element, an antenna substrate, and an antenna module. Background Art

[0002] Japanese Patent Application Laid-Open No. 2015-92658 discloses an antenna element including: a feed patch conductor connected to a feed conductor; a plurality of non-feed patch conductors located above the feed patch conductor; and a plurality of auxiliary patch conductors located at positions not overlapping the feed patch conductor. Summary of the Invention

[0003] Technical means to solve the problem

[0004] The antenna element of the present disclosure includes: a ground conductor; a feed patch conductor located above the ground conductor; and a non-feed patch conductor located above the feed patch conductor.

[0005] The feed patch conductor has a first side and a second side along the resonance direction,

[0006] The non-feed patch conductor has a plurality of segments.

[0007] The plurality of segment bodies include a first segment body arranged along the first side and a second segment body arranged along the second side;

[0008] In a plan view, the total area of ​​the non-feed patch conductors is smaller than the area of ​​the feed patch conductors.

[0009] The antenna substrate of the present disclosure has a plurality of antenna elements.

[0010] The plurality of antenna elements are respectively the above-mentioned antenna elements.

[0011] The antenna module of the present disclosure has:

[0012] the antenna substrate mentioned above; and

[0013] integrated circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1A This is a perspective view showing the antenna element according to the first embodiment of the present disclosure.

[0015] Figure 1B This is a plan view showing the antenna element according to the first embodiment of the present disclosure.

[0016] Figure 2 yes Figure 1B Cross-sectional view at line AA.

[0017] Figure 3AGraphs showing reflection characteristics of the antenna elements of Embodiment 1 and Comparative Example 1, showing frequency characteristics.

[0018] Figure 3B Graphs showing gain curves of frequency characteristics of antenna elements according to Embodiment 1 and Comparative Example 1.

[0019] Figure 4A is the distance d1 between the segmented body and the total width w of the segmented body without the feed patch conductor tot relationship curve diagram.

[0020] Figure 4B It is the distance d1 between the segmented body without the feed patch conductor and the total width w of the segmented body. tot Smith diagram of the relationship.

[0021] Figure 5A This is a first example of a longitudinal cross-sectional view illustrating the minimum distance between the power feeding patch conductor and the non-feeding patch conductor.

[0022] Figure 5B This is a second example of a longitudinal cross-sectional view illustrating the minimum distance between the power feeding patch conductor and the non-feeding patch conductor.

[0023] Figure 6 Graph showing the relationship between the distance d1 of the segment body and the specific frequency band.

[0024] Figure 7A Graphs showing current density distributions of passive patch conductors according to the second embodiment with different distances d1 between segments.

[0025] Figure 7B Graphs showing current density distributions of passive patch conductors according to the third embodiment with different distances d1 between segments.

[0026] Figure 7C Graphs showing current density distributions of passive patch conductors in Comparative Example 2 having different distances d1 between segments.

[0027] Figure 7D Graphs showing current density distributions of passive patch conductors in Comparative Example 3 having different distances d1 between segments.

[0028] Figure 8A 7 is a graph showing the reflection characteristics of the second embodiment.

[0029] Figure 8B 7 is a graph showing the reflection characteristics of the third embodiment.

[0030] Figure 8C It is a graph showing the reflection characteristics of Comparative Example 2 in FIG. 7 .

[0031] Figure 8DIt is a graph showing the reflection characteristics of Comparative Example 3 in FIG. 7 .

[0032] Figure 9 Graph showing the relationship between the distance d1 of the segment and the in-band reflection.

[0033] Figure 10A d1 is a frequency characteristic graph showing the relationship between the distance d1 of the segment and the gain.

[0034] Figure 10B 3 is a graph showing the relationship between the distance d1 of the segment and the gain, and the minimum gain within the frequency band.

[0035] Figure 11 2 is a graph showing the relationship between the minimum distance d2min and the minimum gain within the frequency band.

[0036] Figure 12A This is a cross-sectional view showing an antenna element according to a fourth embodiment.

[0037] Figure 12B Yes Figure 12A A graph showing the relationship between the distance d1b and the minimum gain within the frequency band.

[0038] Figure 13A It is a top view showing the antenna element of the fifth embodiment.

[0039] Figure 13B It is a top view showing the antenna element of the sixth embodiment.

[0040] Figure 14A It is a reflection characteristic graph showing the frequency characteristics of the antenna elements of Embodiments 1, 5, and 6.

[0041] Figure 14B It is a gain curve graph showing the frequency characteristics of the antenna elements of Embodiments 1, 5, and 6.

[0042] Figure 15A This is a cross-sectional view showing an antenna element according to a seventh embodiment in which the total number of segments of the passive patch conductor is three or more.

[0043] Figure 15B This is a cross-sectional view showing an antenna element according to Embodiment 8 in which the total number of segments of the passive patch conductor is three or more.

[0044] Figure 15C This is a cross-sectional view showing an antenna element according to Embodiment 9 in which the total number of segments of the passive patch conductor is three or more.

[0045] Figure 15D This is a cross-sectional view showing an antenna element according to Embodiment 10 in which the total number of segments of the passive patch conductor is three or more.

[0046] Figure 16A It is a reflection characteristic graph showing the frequency characteristics of the antenna elements of Embodiments 1 and 7 to 10.

[0047] Figure 16B It is a gain graph showing the frequency characteristics of the antenna elements of Embodiments 1 and 7 to 10.

[0048] Figure 17A It is a plan view showing an antenna substrate and an antenna module according to an embodiment of the present disclosure.

[0049] Figure 17B yes Figure 17A Cross-sectional view at line BB. DETAILED DESCRIPTION

[0050] Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0051] (Implementation 1)

[0052] Figure 1A and Figure 1B They are respectively a perspective view and a top view showing the antenna element according to the first embodiment of the present disclosure. Figure 2 yes Figure 1B A cross-sectional view taken along line AA of FIG. The following description uses the Z direction in the figure as the vertically downward direction, and the X and Y directions, which are perpendicular to the Z direction, as the horizontal directions. The Z direction is perpendicular to the surface (top surface) of the ground conductor 21 on the feed patch conductor 22 side, while the X and Y directions are two mutually orthogonal directions along the top surface of the ground conductor 21. The up, down, left, and right directions in this specification may differ from those used when the antenna element 1A is used.

[0053] Basic Structure

[0054] The antenna element 1A of the first embodiment includes a ground conductor 21, a feeding patch conductor 22 located above the ground conductor 21, and a non-feeding patch conductor 23 located above the feeding patch conductor 22. The patch conductor is a conductor plate or a conductor film.

[0055] The upper surface of the ground conductor 21 may also extend in a planar shape. The feed patch conductor 22 and the non-feed patch conductor 23 may also be flat. The feed patch conductor 22 and the non-feed patch conductor 23 may be arranged so that one surface of the feed patch conductor 22 and one surface of the non-feed patch conductor 23 are opposite the upper surface of the ground conductor 21. More specifically, the upper surface of the ground conductor 21, the surface of the feed patch conductor 22, and the surface of the non-feed patch conductor 23 may be parallel to each other. The surface refers to two surfaces of the outer surface that are wider than the other surfaces. The surface of the feed patch conductor 22 and the non-feed patch conductor 23 that is opposite the upper surface of the ground conductor 21 is the lower surface.

[0056] The antenna element 1A includes a dielectric substrate 10. A ground conductor 21, a feed patch conductor 22, and a non-feed patch conductor 23 may also be located on the dielectric substrate 10. The dielectric substrate 10 has a laminated structure and may include a plurality of dielectric layers 10a ( Figure 2 The feed patch conductor 22 may be located inside the dielectric substrate 10, and the non-feed patch conductor 23 may be located on the upper surface of the dielectric substrate 10. Furthermore, the ground conductor 21 may be located on the lower surface of the dielectric substrate 10 or inside the dielectric substrate 10.

[0057] The antenna element 1A includes a feed conductor 24 that transmits a transmission signal or a reception signal. The feed conductor 24 may extend in the vertical direction via a through hole 21 a of the ground conductor 21 and be connected to the feed patch conductor 22 .

[0058] According to the antenna element 1A having the above configuration, when power corresponding to a transmission signal in a target frequency band is fed to the feed patch conductor 22 via the feed conductor 24, electrical resonance occurs between the feed patch conductor 22 and the non-feed patch conductor 23 in the resonant direction, and radio waves are radiated from the feed patch conductor 22 and the non-feed patch conductor 23. When the antenna element 1A receives radio waves in the target frequency band from the outside world, electrical resonance occurs between the feed patch conductor 22 and the non-feed patch conductor 23 in the resonant direction, and a received signal is transmitted from the feed patch conductor 22 to the feed conductor 24. The target frequency band refers to the frequency band of radio waves to be transmitted or received.

[0059] <Feed Patch Conductors and Non-Feed Patch Conductors>

[0060] In top view, the feed patch conductor 22 may be quadrilateral, rectangular or square ( Figure 1B ). Looking down means looking from above.

[0061] The feed patch conductor 22 may have a first side 22a and a second side 22b along the resonance direction. The resonance direction corresponds to a direction parallel to a straight line 61 connecting the center 22c of the feed patch conductor 22 and the center of the feed point (the connection point of the feed conductor 24).

[0062] The unfed patch conductor 23 can be divided into a plurality of segments, each having a plurality of segments. The plurality of segments can include a first segment 23a along the first side 22a of the fed patch conductor 22 and a second segment 23b along the second side 22b. "A segment along a certain line segment" means that the segment is located relatively close to the aforementioned line segment compared to other segments, and the length direction of the segment is parallel or nearly parallel to the aforementioned line segment. Nearly parallel means parallel within ±10°.

[0063] In embodiment 1, as Figure 1A As shown, the total number of segments of the non-feed patch conductor 23 can be two. The first segment 23a and the second segment 23b can have the same size and shape, and can also be located at point-symmetrical positions relative to the center 22c of the feed patch conductor 22 in a plan view.

[0064] In a top view, the total area of ​​the passive patch conductor 23, i.e., the total area of ​​the multiple segments ( 23a , 23b ), can be smaller than the area of ​​the feed patch conductor 22 . The structure of the passive patch conductor 23 having multiple segments and the aforementioned area differences can achieve a wider bandwidth and improved gain for the antenna element 1A. Details of this effect are described below in the sections "Antenna Element Characteristics" and "Segment Distance and Width."

[0065] <Simulation parameters>

[0066] Here, we show the results of several simulations. Figure 2 , which shows the parameters used in the simulation. In the simulation, the width w22 of the feed patch conductor 22 is 0.75 mm, the planar shape of the feed patch conductor 22 is a square, the distance a1 between the centers of the thickness of the ground conductor 21 and the feed patch conductor 22 is 0.2 mm, the distance a2 between the centers of the thickness of the ground conductor 21 and the passive patch conductor 23 is 0.4 mm, the relative permittivity of the dielectric substrate 10 is 5.7, and the target frequency band is 64 GHz (specifically, 57 to 71 GHz). Unless otherwise specified, the length of the passive patch conductor 23 in the resonant direction is consistent with the length of the feed patch conductor 22 in the resonant direction, and there is no deviation between the positions of the feed patch conductor 22 and the passive patch conductor 23 in the resonant direction.

[0067] Antenna Element Characteristics

[0068] Figure 3A and Figure 3BThe following are reflection characteristic graphs and gain graphs showing the frequency characteristics of the antenna elements of Embodiment 1 and Comparative Example 1. These graphs are simulation results for antenna element 1A of Embodiment 1 and the antenna element of Comparative Example 1. The same applies to the following reflection characteristic graphs and gain graphs.

[0069] exist Figure 3A and Figure 3B The antenna element of Comparative Example 1 has the same structure as antenna element 1A of Embodiment 1, except for the structure of the passive patch conductor. The passive patch conductor of Comparative Example 1 is a single rectangular (e.g., substantially square) structure, with its center overlapping the feed patch conductor when viewed from above. The passive patch conductor 23 of Embodiment 1 and the passive patch conductor of Comparative Example 1 are sized to achieve impedance matching within the target frequency band.

[0070] like Figure 3A and Figure 3B As shown, the antenna element 1A of Embodiment 1 has less reflection in the target frequency band and higher gain than that of Comparative Example 1. The antenna element 1A of Embodiment 1 has a wider frequency band with a reflection of -10 dB or less and a wider frequency band with a gain of 5 dB or more than that of Comparative Example 1. Therefore, the antenna element 1A of Embodiment 1 achieves a wider bandwidth than that of Comparative Example 1.

[0071] <Segment distance and width>

[0072] Figure 4A and Figure 4B is the distance d1 and total width w of the segmented body of the unfed patch conductor tot and a Smith chart illustrating this relationship. Figure 4A relationship and Figure 4B The impedance characteristics are obtained through simulation results.

[0073] like Figure 2 As shown, the first segment body 23a and the second segment body 23b may have a total width w tot , a distance d1 from the central plane 62. The central plane 62 refers to a virtual vertical plane along the resonance direction passing through the center of the feed patch conductor 22. The total width w tot The distance d1 is the length in the horizontal direction perpendicular to the resonance direction. The width of the first segment 23a is w tot / 2, the width of the second segment 23b is w tot The distance between the first segment 23a and the second segment 23b is 2×d1.

[0074] The impedance of the antenna element 1A depends on the width w tot and distance d1. Figure 4BAs shown in the impedance trajectory, when d1=0[mm], w tot = 0.75 [mm], the impedance locus is close to the center of the graph (i.e., 50Ω) near the center of the target frequency band, and the impedance is matched. tot =0.75[mm], and d1 =0.4[mm], the impedance locus moves upward from the center of the graph near the center of the target frequency band, resulting in impedance mismatch. The center of the target frequency band corresponds to the closed loop portion of the impedance locus.

[0075] In order to make the distance d1 constant and achieve impedance matching, the total width w corresponding to the distance d1 can be selected. tot Generally, a multilayer patch antenna having a fed patch conductor and a non-fed patch conductor has two poles of resonant frequency ω1, ω2 (refer to Figure 3A Furthermore, the two poles ω1 and ω2 have different frequencies, achieving broadband. The resonance of the feed patch conductor mainly contributes to the lower pole ω1, while the resonance of the non-feed patch conductor mainly contributes to the higher pole ω2.

[0076] Therefore, when the impedance locus is located near the center of the target frequency band and above the center of the figure, the total width w of the segments (23a, 23b) of the passive patch conductor 23 can be reduced. tot The capacitance component of the passive patch conductor 23 can be reduced. According to this structure, the impedance trajectory can be brought close to the center of the graph near the center of the target frequency band. Figure 4B As shown, in the case of d1 = 0.4 [mm], by making w tot = 0.5 [mm], the closed loop portion of the impedance trajectory approaches the center of the graph, and the impedance is matched.

[0077] Figure 4A The graph shows the distance d1 and the total width w when the impedance is matched as described above. tot As shown in the graph, when the impedance is matched, within the range where the distance d1 is not too large, the larger the distance d1 is, the larger the total width w is. tot The smaller.

[0078] Figure 4A The point where d1 = 0 [mm] on the graph corresponds to the structure of Comparative Example 1 in which the non-feed patch conductor 23 is a single structure. In this structure, the area of ​​the feed patch conductor 22 is equal to the area of ​​the non-feed patch conductor 23. Therefore, the antenna element 1A of Embodiment 1 with d1 > 0 [mm] corresponds to a width w of 1, which is greater than that of Comparative Example 1. totThe structure of the small size is a structure in which the total area of ​​the non-feed patch conductor 23 is smaller than the area of ​​the feed patch conductor 22. Moreover, according to this structure, impedance matching is achieved, and the broadband and gain improvement of the antenna element 1A are achieved. That is, according to the structure in which the non-feed patch conductor 23 has a plurality of segments and the total area of ​​the non-feed patch conductor 23 is smaller than the area of ​​the feed patch conductor 22, as shown in FIG. Figure 3A and Figure 3B As shown, the antenna element 1A can have a wider bandwidth and improve gain.

[0079] <Range of segment distance d1 and minimum distance d2min>

[0080] Figure 5A and Figure 5B These are the first and second examples of longitudinal cross-sectional views illustrating the minimum distance between the power feeding patch conductor and the non-feeding patch conductor.

[0081] Here, the minimum distance d2min between the feeding patch conductor 22 and the non-feeding patch conductor 23 is introduced. Figure 5A ), the minimum distance d2min between the feed patch conductor 22 and the non-feed patch conductor 23 is the length of the vertical distance between the feed patch conductor 22 and the non-feed patch conductor 23. Therefore, in this structure, the minimum distance d2min does not depend on the distance d1. On the other hand, in a structure where the feed patch conductor 22 and the non-feed patch conductor 23 do not overlap in a plan view ( Figure 5B ), since the horizontal component is applied, the larger the distance d1 is, the larger the minimum distance d2min is.

[0082] The distance d1 between the segments (23a, 23b) of the passive patch conductor 23 can be greater than 0, and the minimum distance d2min between the feed patch conductor 22 and the passive patch conductor 23 can be within the range of (1 / 8) × λ or less. When the parameters of the above simulation are applied, the condition of d2min ≤ (1 / 8) × λ is roughly equivalent to d1 ≤ 0.514.

[0083] The above-mentioned λ corresponds to the effective wavelength corresponding to the center frequency of the target frequency band. Specifically, λ = c / (f × √Er), where c is the speed of light, f is the center frequency (e.g., 64 GHz), and Er is the relative permittivity of the dielectric substrate 10. By using the effective wavelength λ of the target frequency band to define the range of the segment distance d1, this definition can be applied even to antenna elements with different target frequency bands.

[0084] Next, refer to Figures 6 to 11 The characteristics of the antenna element having the distance d1 and the minimum distance d2min defined as described above will be described.

[0085] Figure 6 This is a graph showing the relationship between the distance d1 of the segment and the relative bandwidth. The vertical axis of the graph represents the width of the frequency band where the reflection is -10 dB or less as a ratio (also called relative bandwidth). This graph was obtained based on simulation results. In the simulation, the total width w of the segment (23a, 23b) tot A value (the value in FIG. 4 ) that allows impedance matching corresponding to the distance d1 is employed.

[0086] exist Figure 6 In the case where d1=0 [mm], the specific frequency band represents the value of Comparative Example 1 (the feed patch conductor 22 is a single structure). In the case where the feed patch conductor 23 has two segments (23a, 23b), Figure 6 In the range 71 , the specific frequency band increases as the distance d1 increases, and in the range 72 , the specific frequency band decreases as the distance d1 increases.

[0087] The increase in the frequency band in range 71 is due to the fact that Figure 4B As shown in the Smith chart, as the distance d1 increases, the closed loop portion of the impedance locus becomes smaller, and the impedance is better matched in the target frequency band.

[0088] Next, the reason why the frequency band is reduced in the range 72 will be described with reference to FIG. 7 .

[0089] Figures 7A to 7D Graphs respectively show the current density distributions of passive patch conductors in Embodiment 2, Embodiment 3, Comparative Example 2, and Comparative Example 3, each with different segment distances d1. Figures 8A to 8D 7 are graphs showing the reflection characteristics of embodiment 2, embodiment 3, comparative example 2, and comparative example 3, respectively. The above current density distribution and reflection characteristics are obtained by simulation. Figures 7A to 7D The concentrated portion corresponds to the portion with high current density.

[0090] Figure 7A The antenna element 1B of the second embodiment has d1 = 0.2 [mm]. Figure 7B The antenna element 1C of the third embodiment has d1 = 0.4 [mm].

[0091] Figure 7C The antenna element 52 of Comparative Example 2 has d1 = 0.6 [mm]. Figure 7D The antenna element 53 of Comparative Example 3 has a width w of d1 = 0.7 [mm]. tot The values ​​obtained by impedance matching corresponding to the distance d1 are used.

[0092] like Figure 7C and Figure 7DAs shown, by making the passive patch conductor 23 farther away from the feeding patch conductor 22, the electrical interaction between the feeding patch conductor 22 and the passive patch conductor 23 is reduced, and the electrical resonance of the passive patch conductor 23 during radio wave transmission is reduced. Figure 8C and Figure 8D As shown, in the structure where the passive patch conductor 23 is far away, the resonance frequency pole ω2 becomes shallower or one pole ω2 disappears. Therefore, the frequency band where the reflection is below -10dB becomes narrower. For this reason, Figure 6 The greater the distance d1 is within the range 72, the smaller the specific frequency band is.

[0093] Figure 6 The graph of the bandwidth ratio shows that, under the conditions where distance d1 is greater than 0 and the minimum distance d2min is less than or equal to (1 / 8) × λ (i.e., d1 ≤ 0.514), a wider bandwidth can be achieved compared to the configuration of Comparative Example 1 (d1 = 0). In other words, the antenna elements 1A, 1B, and 1C of Embodiments 1 to 3, which meet these conditions, achieve a wider bandwidth compared to Comparative Example 1. Furthermore, the minimum distance d2min does not necessarily need to be less than or equal to (1 / 8) × λ; even within a range greater than this value, superior frequency characteristics, such as improved reflection characteristics within the frequency band, can be achieved compared to Comparative Examples 1 to 3.

[0094] Figure 9 This is a graph showing the relationship between the distance d1 of the segment and the in-band reflection. In-band reflection refers to the reflection within the frequency range of the object. This graph was obtained through simulation. Figure 4B As shown in the Smith chart, as the distance d1 increases, the closed loop portion of the impedance locus becomes smaller, and the impedance is more closely matched within the target frequency band. As a result, reflections within the band decrease. Figure 9 The graph of the in-band reflection shows that the greater the distance d1 is than 0, the more the in-band reflection decreases.

[0095] Figure 10A and Figure 10B It is a frequency characteristic graph showing the relationship between the distance d1 of the segment body and the gain and a graph showing the minimum gain within the frequency band. Figure 11 This is a graph showing the relationship between the minimum distance d2min and the minimum gain within the frequency band. The minimum gain within the frequency band refers to the minimum value of the gain in the target frequency band. This graph was obtained through simulation. Figure 10A As shown, d1 = 0.1 [mm] to 0.4 [mm], and the gain is improved compared with Comparative Example 1 in which d = 0 [mm] in the entire region of the target frequency band.

[0096] The magnitude of the gain in the target frequency band has a tendency that is substantially consistent with the magnitude of the minimum gain in the frequency band. Figure 10B and Figure 11The graph shows that under the conditions where the distance d1 is greater than 0 and the minimum distance d2min is less than 1 / 8×λ (=1.25λ) (i.e., d1≤0.514), the minimum gain within the frequency band is greater than that of Comparative Example 1 where d1=0. That is, the antenna elements 1A, 1B, and 1C of Embodiments 1 to 3 that satisfy the above conditions can improve the gain in the target frequency band compared to Comparative Examples 1 to 3. Figure 10B and Figure 11 In the graph of , the minimum gain within the frequency band of Comparative Example 1 is indicated by a dotted line.

[0097] The structure d1 = 0.4 [mm] where the minimum gain in the frequency band is close to the maximum value is a structure where the feed patch conductor 22 does not overlap with the first segment 23a and the second segment 23b of the non-feed patch conductor 23 in a plan view. Therefore, in this structure, the gain can be further improved.

[0098] Asymmetry of Segments Without Feed Patch Conductors

[0099] Figure 12A This is a cross-sectional view showing an antenna element according to a fourth embodiment. Figure 12B Yes Figure 12A The graph shows the relationship between the distance d1b and the minimum gain within the frequency band. This graph was obtained through simulation.

[0100] The antenna element 1D according to the fourth embodiment is the same as the antenna elements 1A, 1B, and 1C according to the first to third embodiments except that the positional symmetry of the first segment body 23a and the second segment body 23b may be different.

[0101] The distance d1a between the first segment 23a and the central plane 62 may be different from the distance d1b between the second segment 23b and the central plane 62. The central plane 62 is a virtual vertical plane along the resonance direction passing through the center of the feed patch conductor 22. Figure 12B The graph shows the minimum gain within the frequency band when d1a=0.4 [mm] is fixed and d1b is changed within the range of d1b=0.3 to 0.5 [mm].

[0102] This graph shows that regardless of whether the positions of the first segment 23a and the second segment 23b are symmetrical or asymmetrical (specifically, their positions in the horizontal direction perpendicular to the resonance direction), a higher gain is achieved compared to the antenna element of Comparative Example 1. The minimum gain within the frequency band of Comparative Example 1 is 5.6 dB. Furthermore, symmetrical positions significantly improve the gain compared to asymmetrical positions.

[0103] Although not shown in the figure, simulation results of reflection characteristics show that the frequency band where the reflection is -10 dB or less is wider than that of Comparative Example 1, regardless of whether the first segment 23a and the second segment 23b are positioned symmetrically or asymmetrically, achieving a wider bandwidth. Furthermore, it was shown that the symmetrical position achieves a wider bandwidth than the asymmetrical position.

[0104] Furthermore, although not shown in the figure, simulation results of the radiation pattern show that even if the positions of the first segment body 23a and the second segment body 23b are asymmetric, the radiation pattern in the YZ direction does not change significantly from the case of a symmetric structure.

[0105] Therefore, according to the antenna element 1D of the fourth embodiment, it is possible to achieve a wider bandwidth and improve the gain compared to the first comparative example.

[0106] <Regarding the length of the passive patch conductor in the resonance direction>

[0107] Figure 13A and Figure 13B These are plan views showing antenna elements according to the fifth and sixth embodiments, respectively. Figure 14A and Figure 14B 14 is a reflection characteristic graph and a gain graph showing the frequency characteristics of the antenna elements of Embodiments 1, 5, and 6. The graph of FIG14 was obtained by simulation.

[0108] The antenna elements 1E and 1F of embodiments 5 and 6 are similar to the antenna elements 1A to 1C of embodiments 1 to 3 except that the length L of the first segment 23a and the second segment 23b in the resonance direction and the length of the feed patch conductor 22 in the resonance direction may be different.

[0109] Embodiment 5 is an example in which the passive patch conductor 23 is longer than the feeding patch conductor 22 (L = 0.85 mm). Embodiment 6 is an example in which the passive patch conductor 23 is shorter than the feeding patch conductor 22 (L = 0.70 mm). The widths of the segments (23a, 23b) are adjusted to 0.11 mm and 0.41 mm, respectively, to achieve impedance matching corresponding to the difference in length L in the resonance direction. In Embodiment 1, the passive patch conductor 23 and the feeding patch conductor 22 have the same length (L = 0.75 mm), and the width of each segment (23a, 23b) is 0.25 mm. In Embodiments 1, 5, and 6, the distance d1 between the segments is 0.4 mm.

[0110] Figure 14A The graph shows that the antenna elements 1E and 1F of the fifth and sixth embodiments achieve a wider bandwidth (specifically, a wider bandwidth of the frequency where the reflection is −10 dB) than the antenna element of the first comparative example. Figure 14BThe graph shows that the antenna elements 1E and 1F of Embodiments 5 and 6 have improved gain compared to the antenna element of Comparative Example 1. Furthermore, the antenna element 1A of Embodiment 1, in which the lengths L in the resonance direction of the non-feed patch conductor 23 and the feeding patch conductor 22 are equal, has lower reflection in the target frequency band and improved gain compared to the antenna elements 1E and 1F of Embodiments 5 and 6.

[0111] The difference in characteristics based on the length L of the passive patch conductor 23 is due to the following reasons. Specifically, to achieve impedance matching, the width of each segment (23a, 23b) of the passive patch conductor 23 is adjusted according to the length L. As a result, as the length L increases, the area of ​​the segments (23a, 23b) decreases, while as the length L decreases, the area of ​​the segments (23a, 23b) increases. This change in area varies the capacitance component of the passive patch conductor 23, causing the value of the pole ω2 at the higher resonant frequency to shift toward higher and lower values, respectively. Furthermore, the aforementioned difference in characteristics arises as the value of the pole ω2 changes.

[0112] like Figure 14A and Figure 14B As shown in the graph, even if the lengths L of the passive patch conductor 23 and the feeding patch conductor 22 in the resonant direction differ, broadbanding and improved gain can be achieved. Specifically, the length L of the passive patch conductor 23 in the resonant direction can be within a range of ±15% of the length of the feeding patch conductor 22 in the resonant direction. Even with this structure, broadbanding and improved gain can be achieved. Furthermore, by making the lengths of the passive patch conductor 23 and the feeding patch conductor 22 consistent in the resonant direction, further broadbanding and improved gain can be achieved. Length consistency not only includes strict consistency but also includes situations where the length difference is within the tolerance. For example, this tolerance is within the tolerance range.

[0113] <Structure with three or more segments of non-feed patch conductors>

[0114] Figures 15A to 15D These are cross-sectional views showing antenna elements according to Embodiment 7, Embodiment 8, Embodiment 9, and Embodiment 10, respectively, in which the total number of segments of the passive patch conductor is three or more. Figure 16A and Figure 16B These are a reflection characteristic graph and a gain graph showing the frequency characteristics of the antenna elements of Embodiments 1 and 7 to 10, respectively.

[0115] The antenna elements 1G to 1J of embodiments 7 to 10 are similar to the antenna element 1A of embodiment 1, except for the structure of the passive patch conductor 23. The length of the passive patch conductor 23 in the resonant direction can also be the same as that of the antenna element 1A of embodiment 1. In embodiments 7 to 10, the width of each of the plurality of segments (23a to 23d) of the passive patch conductor 23 is represented by w. a ~w d .

[0116] The antenna element 1G of the seventh embodiment has a relatively small width (w c =0.05 [mm]) is located in the center of the horizontal direction. The horizontal direction corresponds to the horizontal direction perpendicular to the resonance direction. The antenna element 1H of embodiment 8 is adjusted so that the width (w) of the first to third segments 23a to 23c is aligned with the target frequency band at the center of the resonance frequency (i.e., between the two poles ω1 and ω2). a =w b =w c =0.18 [mm]). The antenna element 1I of the ninth embodiment is a small width (w c =w d =0.05mm) is located between the first segment 23a and the second segment 23b. The third segment 23c can be located near the first segment 23a rather than at the center, and the fourth segment 23d can be located near the second segment 23a rather than at the center. The antenna element 1J of embodiment 10 adjusts the widths (w) of the third segment 23c and the fourth segment 23d so that the centers of the resonant frequencies ω1 and ω2 coincide with the target frequency band. c =w d =0.1mm).

[0117] In the antenna elements 1G to 1J of the seventh to tenth embodiments, the total width w of the plurality of segments of the non-feed patch conductor 23 is tot The width of the non-feed patch conductor 23 is smaller than the width of the feed patch conductor 22 . Therefore, in the antenna elements 1G to 1J of the seventh to tenth embodiments, the total area of ​​the non-feed patch conductor 23 is smaller than the area of ​​the feed patch conductor 22 .

[0118] Figure 16A and Figure 16B The graph shows that antenna elements 1G to 1J of embodiments 7 to 10 achieve wideband and improved gain. Furthermore, the graph shows that antenna element 1A of embodiment 1 has lower reflection in the target frequency band and improved gain compared to antenna elements 1G to 1J of embodiments 7 to 10.

[0119] As shown in the above graph, even if the total number of segments of the passive patch conductor 23 is three or more, broadband and increased gain can be achieved. Furthermore, by configuring the passive patch conductor 23 with a total number of segments of two, broadband and increased gain can be achieved even further.

[0120] (Antenna substrate and antenna module)

[0121] Figure 17A It is a plan view showing an antenna substrate and an antenna module according to an embodiment of the present disclosure. Figure 17B Yes Figure 17A Longitudinal section view at line BB.

[0122] Antenna substrate 110 of this embodiment includes a plurality of antenna elements 1A. Antenna element 1A is antenna element 1A of Embodiment 1, but may be replaced by antenna elements 1B to 1J of Embodiments 2 to 10. The plurality of antenna elements 1A may be arranged vertically and horizontally in a matrix or other configurations on large array dielectric substrate 10.

[0123] Antenna substrate 110 may include an electrode 130 connected to an integrated circuit 200 that at least outputs a transmission signal or inputs a reception signal, and a transmission path 120 that transmits signals between electrode 130 and each antenna element 1A. A portion of transmission path 120 may be a feed conductor 24 for each antenna element 1A.

[0124] The antenna substrate 110 may be equipped with a filter circuit for extracting a signal of a desired frequency band from the signal of the transmission path 120 .

[0125] The antenna module 100 of this embodiment includes an antenna substrate 110 and an integrated circuit 200. The integrated circuit 200 may be bonded to the side of the antenna substrate 110 opposite to the side from which radio waves are radiated.

[0126] The antenna substrate 110 and antenna module 100 of this embodiment enable at least one of broadband radio wave transmission and reception. Furthermore, since broadband radio wave transmission is possible, it is easy to add a phase difference to the transmitted radio waves between the multiple antenna elements 1A. Furthermore, by adding a phase difference, the radio waves can be beamformed and output at a desired angle. Therefore, the antenna substrate 110 and antenna module 100 of this embodiment facilitate beamforming. Furthermore, the multiple antenna elements 1A have high gain, making it easy to use in wireless communications in frequency bands with significant atmospheric attenuation.

[0127] The embodiments of the present disclosure have been described above. However, the antenna element, antenna substrate, and antenna module of the present disclosure are not limited to the above-described embodiments. The details described in the embodiments may be modified as appropriate without departing from the spirit of the invention.

[0128] Hereinafter, an embodiment of the present disclosure is shown. In one embodiment,

[0129] (1) An antenna element, wherein:

[0130] The invention comprises: a ground conductor; a feed patch conductor located above the ground conductor; and a non-feed patch conductor located above the feed patch conductor;

[0131] The feed patch conductor has a first side and a second side along the resonance direction,

[0132] The non-feed patch conductor has a plurality of segments.

[0133] The plurality of segment bodies include a first segment body arranged along the first side and a second segment body arranged along the second side;

[0134] In a plan view, the total area of ​​the non-feed patch conductors is smaller than the area of ​​the feed patch conductors.

[0135] (2) The antenna element according to (1) above, wherein:

[0136] The total number of the segments of the passive patch conductor is two.

[0137] (3) The antenna element according to (1) or (2) above, wherein:

[0138] In a plan view, the first segment and the second segment do not overlap with the feed patch conductor.

[0139] (4) The antenna element according to any one of (1) to (3) above, wherein:

[0140] The minimum distance between the non-feed patch conductor and the feed patch conductor is less than (1 / 8)×λ, where λ is an effective wavelength corresponding to the center frequency of the signal band.

[0141] (5) The antenna element according to any one of (1) to (4) above, wherein:

[0142] In a longitudinal section perpendicular to the resonance direction, the non-feed patch conductor is line-symmetrical with respect to a line segment that intersects the center of the feed patch conductor and is perpendicular to the upper surface of the feed patch conductor.

[0143] (6) The antenna element according to any one of (1) to (5) above, wherein:

[0144] The length of the feeding patch conductor in the resonance direction is the same as the length of the non-feed patch conductor in the resonance direction.

[0145] In one embodiment,

[0146] (7) An antenna substrate, wherein:

[0147] having a plurality of antenna elements,

[0148] The plurality of antenna elements are respectively the antenna elements described in any one of (1) to (6) above.

[0149] In one embodiment,

[0150] (8) An antenna module, wherein:

[0151] have:

[0152] The antenna substrate of (7) above; and

[0153] integrated circuit.

[0154] Industrial applicability

[0155] The present disclosure can be utilized in an antenna element, an antenna substrate, and an antenna module.

[0156] Description of Reference Numerals

[0157] 1A to 1J antenna elements

[0158] 10Dielectric substrate

[0159] 21 grounding conductor

[0160] 22 Feed patch conductor

[0161] 22a First side

[0162] 22b Second side

[0163] 23 Non-feed patch conductor

[0164] 23a First segment

[0165] 23b Second segment

[0166] 23c third segment

[0167] 23d fourth segment

[0168] 24 feed conductors

[0169] w tot Total width

[0170] d1, d1a, d1b distances

[0171] d2min minimum distance

[0172] ω1, ω2 poles

[0173] 62 Central Plane

[0174] 100 antenna modules

[0175] 110 antenna substrate

[0176] 200 integrated circuits

Claims

1. An antenna element, wherein: It has: a grounding conductor; A feed patch conductor, located above the ground conductor; and a non-feed patch conductor, located above the feed patch conductor; The feed patch conductor has a first side and a second side along a resonance direction, The non-feed patch conductor has a plurality of segmented bodies. The plurality of segment bodies include a first segment body arranged along the first side and a second segment body arranged along the second side; In a plan view, the total area of ​​the non-feed patch conductors is smaller than the area of ​​the feed patch conductors.

2. The antenna element according to claim 1, wherein: The total number of the segmented bodies of the non-feed patch conductor is two.

3. The antenna element according to claim 1, wherein: In a plan view, the first segment body and the second segment body do not overlap with the feeding patch conductor.

4. The antenna element according to claim 1, wherein: The minimum distance between the non-feed patch conductor and the feed patch conductor is less than (1 / 8)×λ, where λ is an effective wavelength corresponding to the center frequency of a signal frequency band.

5. The antenna element according to claim 1, wherein: In a longitudinal section perpendicular to the resonance direction, the non-feed patch conductor is line-symmetrical with respect to a line segment intersecting the center of the feed patch conductor and perpendicular to the upper surface of the feed patch conductor.

6. The antenna element according to claim 1, wherein: The length of the feeding patch conductor in the resonance direction is the same as the length of the non-feeding patch conductor in the resonance direction.

7. An antenna substrate, wherein: having a plurality of antenna elements, The plurality of antenna elements are respectively the antenna elements according to claim 1.

8. An antenna module, wherein: have: The antenna substrate according to claim 7; and integrated circuit.

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