Filtering integrated antenna structure

Abstract

The invention discloses a filtering integrated antenna structure, and relates to the technical field of communication, the filtering integrated antenna structure comprises an antenna assembly and a filter assembly, the antenna assembly comprises a substrate, a radiation patch, a reflecting plate, a feed part and a plurality of metal columns, the substrate is provided with a first end and a second end which are opposite, the reflecting plate is arranged at the first end of the substrate, and the feed part is arranged at the second end of the substrate. The radiation patch is arranged between the first end and the second end, the multiple metal columns penetrate through the substrate at intervals in the direction from the second end to the first end so as to define an electromagnetic shielding cavity, the radiation patch is provided with a first through hole and a second through hole, and the feed part is arranged at the second end of the substrate; the filter assembly is arranged in the electromagnetic shielding cavity, and the filter assembly and the radiation patch are arranged at an interval; according to the technical scheme provided by the invention, the filter assembly can be integrated at high density in the antenna, and the filtering performance and the radiation performance of the filtering integrated antenna structure can be improved.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and particularly to a filtering integrated antenna structure. Background Art

[0002] With the rapid development of modern wireless communication technologies, radio frequency (RF) front-end systems are facing great demands and challenges in terms of integration, miniaturization, high performance, etc. Antennas and filters play key roles in RF front-end systems, and their collaborative performance profoundly affects communication efficiency and service quality.

[0003] In the layout of traditional RF front-end systems, antennas and filters are usually independently designed and cascaded, occupying a large amount of structural space and introducing a large amount of interconnection loss, which limits their application in compact and miniaturized systems. In recent years, filtering antennas with collaborative design of antennas and filters have emerged in the industry, including two methods: the cascading method and the filtering fusion method. The cascading method is to cascade the end of a filter with the same impedance and the antenna signal input end for integrated design, and then perform matching adjustment on the whole. The filtering characteristic introduction method refers to directly introducing means such as patch slots, shorting vias, parasitic patches, open / short branches, and electromagnetic coupling in the antenna to generate radiation nulls, so no separate filter is required. Both of these methods have performance interference problems such as insufficient frequency selection effect and deteriorated radiation pattern under high integration. In addition, the current methods also have limitations in the applicable types of antennas and filters. These problems limit the application of related technologies in modern wireless communication systems with limited space size and strict performance requirements. Therefore, there is an urgent need in the industry for new methods and new designs of filtering antennas that can improve the structural integration while ensuring high performance of filtering and antenna radiation. Summary of the Invention

[0004] The main objective of the present invention is to propose a filtering integrated antenna structure, aiming to achieve high performance of overall filtering and radiation while improving the high integration of the filtering antenna structure.

[0005] To achieve the above objective, a filtering integrated antenna structure proposed by the present invention includes:

[0006] An antenna assembly, comprising a substrate, a radiation patch, a reflector, a feeding member and a plurality of metal posts. The substrate has opposite first and second ends. The reflector is disposed at the first end of the substrate. The radiation patch is disposed between the first end and the second end. The plurality of metal posts penetrate the substrate at intervals along the direction from the second end to the first end to enclose an electromagnetic shielding cavity. The radiation patch has a first through hole and a second through hole. The feeding member is disposed at the second end of the substrate. A part of the feeding member sequentially penetrates the first through hole, the substrate and is connected to the reflector along the direction from the second end to the first end. Another part of the feeding member is arranged horizontally and is located above the second through hole. The feeding member is spaced from the radiation patch;

[0007] A filter assembly, the filter assembly is disposed in the electromagnetic shielding cavity. The filter assembly is spaced from the radiation patch. One of the filter assembly and the feeding member passes through the second through hole and is connected to the other.

[0008] In one embodiment, the filter assembly includes two filters spaced horizontally. Both of the two filters are provided with connection ends;

[0009] The reflector has two via holes respectively for the connection ends to pass through. The diameter of the via hole is larger than the diameter of the connection end. The connection end is spaced from the via hole;

[0010] The feeding member includes two sub-feeding members;

[0011] Both the first through hole and the second through hole are provided with two, respectively for the two sub-feeding members to pass through or the two sub-feeding members and the two filters to be connected through.

[0012] In one embodiment, the connection ends of the two filters are respectively used for externally connecting equal-amplitude differential signals with a 180° phase difference, so that the filtering integrated antenna structure performs differential feeding.

[0013] In one embodiment, the distance between the two filters is 0.3 to 0.7 mm.

[0014] In one embodiment, the feeding member includes a feeding post and a microstrip line connected in sequence. A part of the feeding post passes through the first through hole and the substrate and is electrically connected to the feeding point of the reflector. One end of the microstrip line is connected to the feeding post, and the other end is connected to the filter assembly;

[0015] The microstrip line includes a first connection section and a second connection section connected in sequence. The connection part of the first connection section and the second connection section is bent.

[0016] In one embodiment, one end of each of the metal posts is connected to the reflector, and the other end is connected to the radiation patch. A plurality of the metal posts, together with a part of the reflector and a part of the radiation patch, enclose to form the electromagnetic shielding cavity.

[0017] In one embodiment, the diameter of the metal post is D, and D satisfies D < 0.2λ g ;

[0018] The spacing between two adjacent metal posts is S, and S satisfies S ≤ 2D;

[0019] where λ g is the guided wavelength with the center frequency in the preset frequency range.

[0020] In one embodiment, the substrate includes a first dielectric plate, a second dielectric plate, a third dielectric plate, a fourth dielectric plate, a fifth dielectric plate, a sixth dielectric plate, and a seventh dielectric plate. A plurality of dielectric plates are stacked to form eight wiring layers, which are, from top to bottom, the first wiring layer, the second wiring layer, the third wiring layer, the fourth wiring layer, the fifth wiring layer, the sixth wiring layer, the seventh wiring layer, and the eighth wiring layer. The radiation patch is disposed on the second wiring layer, the reflector is disposed on the eighth wiring layer, the microstrip line of the feeding member is disposed on the first wiring layer, and the first dielectric plate is located between the microstrip line of the feeding member and the radiation patch.

[0021] In one embodiment, the filter component includes a dual-mode resonator, an input transmission member, and an output transmission member. The dual-mode resonator includes a first resonant component and a second resonant component in an up-and-down structure. The first resonant component and the second resonant component are connected by a connecting member. The input transmission member is electrically coupled to the first end of the dual-mode resonator, and the output transmission member is electrically coupled to the second end of the dual-mode resonator. The input transmission member is disposed on the seventh dielectric plate and sequentially passes through the seventh wiring layer and the eighth wiring layer along the direction from the first end to the second end. The output transmission member is disposed on the sixth dielectric plate and sequentially passes through the sixth wiring layer, the fifth wiring layer, the fourth wiring layer, the third wiring layer, the second wiring layer, and the first wiring layer along the direction from the second end to the first end. The first resonant component and the second resonant component are disposed on opposite sides along the direction from the first end to the second end of any dielectric plate between the first dielectric plate and the seventh dielectric plate.

[0022] In one embodiment, the first dielectric plate, the third dielectric plate, the fifth dielectric plate, and the seventh dielectric plate are Rogers RO4350B, and the second dielectric plate, the fourth dielectric plate, and the sixth dielectric plate are Rogers RO4450F; the thickness of the first dielectric plate is 0.168 mm, the thicknesses of the third dielectric plate, the fifth dielectric plate, and the seventh dielectric plate are all 0.508 mm, and the thicknesses of the second dielectric plate, the fourth dielectric plate, and the sixth dielectric plate are all 0.2 mm;

[0023] And / or, the length and width of the substrate are both 20 mm, and the height is 2.29 mm.

[0024] Through such an arrangement, the technical solution of the present invention can not only solve the problem of highly integrated filter components and antenna components, but also effectively solve the problem that the performance deteriorates due to interference after the high integration of filter components and antenna components, so that high-density integration of filters can be achieved in a small-scale space inside the antenna while achieving high performance in filtering and radiation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0026] Figure 1 FIG. is a schematic structural diagram of an embodiment of the filter-integrated antenna structure provided by the present invention;

[0027] Figure 2 For Figure 1 the schematic structural diagram of the antenna component in;

[0028] Figure 3 For Figure 1 the schematic structural diagram of the filter component in;

[0029] Figure 4 For Figure 1 the schematic diagram of the split structure of the filter-integrated antenna structure in;

[0030] Figure 5 FIG. is a cross-sectional view of the filter-integrated antenna structure provided by the present invention;

[0031] Figure 6 FIG. is a simplified schematic diagram of the filter-integrated antenna structure provided by the present invention;

[0032] Figure 7Schematic diagram of the feeding component provided by the present invention passing through the radiation patch and connecting to the reflector;

[0033] Figure 8 Schematic diagram of the simulated S-parameters and gain of an embodiment of the antenna assembly provided by the present invention;

[0034] Figure 9 Simulated radiation pattern of an embodiment of the antenna assembly provided by the present invention;

[0035] Figure 10 Schematic diagram of the simulated S-parameter performance in an embodiment of the filter component provided by the present invention;

[0036] Figure 11 Schematic diagram of the performance of the filter component provided by the present invention with respect to the change of the g2 parameter;

[0037] Figure 12 Schematic diagram of the simulated and measured S-parameters and gain performance of an embodiment of the filter-integrated antenna provided by the present invention;

[0038] Figure 13 Simulated and measured radiation patterns in the E-plane of the filter-integrated antenna provided by the present invention at 9.4 GHz;

[0039] Figure 14 Simulated and measured radiation patterns in the E-plane of the filter-integrated antenna provided by the present invention at 9.8 GHz;

[0040] Figure 15 Simulated and measured radiation patterns in the E-plane of the filter-integrated antenna provided by the present invention at 10.4 GHz;

[0041] Figure 16 Simulated and measured radiation patterns in the H-plane of the filter-integrated antenna provided by the present invention at 9.4 GHz;

[0042] Figure 17 Simulated and measured radiation patterns in the H-plane of the filter-integrated antenna provided by the present invention at 9.8 GHz;

[0043] Figure 18 Simulated and measured radiation patterns in the H-plane of the filter-integrated antenna provided by the present invention at 10.4 GHz;

[0044] Figure 19 Schematic diagram of the structure of another embodiment of the filter-integrated antenna structure provided by the present invention.

[0045] Explanation of the reference numerals in the drawings:

[0046] 1. Filter integrated antenna structure; 10. Antenna assembly; 11. Substrate; 111. First dielectric plate; 112. Second dielectric plate; 113. Third dielectric plate; 114. Fourth dielectric plate; 115. Fifth dielectric plate; 116. Sixth dielectric plate; 117. Seventh dielectric plate; 12. Reflector; 121. Via hole; 13. Radiation patch; 131. First through hole; 132. Second through hole; 14. Feeding member; 141. Feeding post; 142. Microstrip line; 15. Metal post; 151. Electromagnetic shielding cavity; 20. Filter assembly; 21. Input transmission member; 211. Connection end; 22. Output transmission member; 23. Dual-mode resonator; 231. First resonance component; 232. Second resonance component; 233. Connection portion.

[0047] The realization, functional features and advantages of the object of the present invention will be further described in conjunction with the embodiments and with reference to the accompanying drawings. Specific embodiments

[0048] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0049] It should be noted that if there are directional indications (such as up, down, left, right, front, back,...) involved in the embodiments of the present invention, the directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0050] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In addition, if "and / or" or "and / or" appears throughout the text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution where A and B are satisfied simultaneously. In addition, the technical solutions between the embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0051] The present invention proposes a filter integrated antenna structure 1.

[0052] Please refer to Figure 1 In an embodiment of the present invention, the filtering integrated antenna structure 1 includes an antenna assembly 10 and a filter assembly 20. Among them, the antenna assembly 10 includes a substrate 11, a radiation patch 13, a reflector 12, a feeding member 14, and a plurality of metal posts 15. The substrate 11 has opposite first and second ends. The reflector 12 is disposed at the first end of the substrate 11. The radiation patch 13 is disposed between the first end and the second end. The plurality of metal posts 15 penetrate the substrate 11 at intervals along the direction from the second end to the first end to enclose an electromagnetic shielding cavity 151. The radiation patch 13 has a first through hole 131 and a second through hole 132. The feeding member 14 is disposed at the second end of the substrate 11. A part of the feeding member 14 penetrates the first through hole 131, the substrate 11, and is connected to the reflector 12 in sequence along the direction from the second end to the first end. Another part of the feeding member 14 is arranged horizontally and is located above the second through hole 132. The feeding member 14 is spaced from the radiation patch 13. The filter assembly 20 is disposed in the electromagnetic shielding cavity 151. The filter assembly 20 is spaced from the radiation patch 13. One of the filter assembly 20 and the feeding member 14 passes through the second through hole 132 and is connected to the other one.

[0053] The antenna assembly 10 of the technical solution of the present invention includes a substrate 11, a radiation patch 13, a reflector 12, a feeding member 14, and a plurality of metal posts 15. Among them, the substrate 11 has opposite first and second ends, specifically the first end and the second end formed along the thickness direction of the substrate 11. The first end is located below and the second end is located above. In this embodiment, it is worth mentioning that the substrate 11 is a multi-layer structure. The reflector 12 is disposed at the first end. The radiation patch 13 is disposed between the first end and the second end, that is, disposed between the multi-layer substrates 11 and is spaced from the reflector 12. A part of the feeding member 14 passes through the radiation patch 13 and the substrate 11 and is connected to the reflector 12. Another part of the feeding member 14 is located on the substrate 11 and is spaced from the radiation patch 13. To enable the feeding member 14 to pass through the radiation patch 13 and the substrate 11 smoothly, in this embodiment, a first through hole 131 is opened on the radiation patch 13. When the feeding member 14 is formed, a part of the feeding member 14 can be passed through the first through hole 131 and the substrate 11 in sequence along the direction from the second end to the first end and is connected to the reflector 12. It should be noted that the aperture of the first through hole 131 should be larger than the diameter of the penetrated part of the feeding member 14, so that a part of the feeding member 14 passes through the first through hole 131 and keeps a spaced state from the radiation patch 13.

[0054] Regarding the partial feed element 14 passing through the substrate 11, it can be integrally provided when the substrate 11 is processed and formed. For example, when the substrate 11 is formed by laminating multiple substrates, the feed element 14 can be formed by connecting the conductive parts provided on multiple substrates 11. There are no excessive limitations on the specific setting of the feed element 14.

[0055] In this embodiment, the filter component 20 is formed together with the substrate 11, that is, the filter component 20 is processed together with the substrate 11 by a processing method similar to the above, so that the filter component 20 is arranged inside the substrate 11 to achieve the effect of reducing the volume of the filter integrated antenna structure 1. However, there is still a problem of poor filtering effect. In this embodiment, a plurality of metal posts 15 are penetrated through the substrate 11. The plurality of metal posts 15 are arranged at intervals from each other and enclose an electromagnetic shielding cavity 151 on the substrate 11, and the filter component 20 is arranged inside the electromagnetic shielding cavity 151. In order to enable the filter component 20 to be connected to the feed element 14, in this embodiment, a second through hole 132 is further opened in the radiation patch 13, and another part of the feed element 14 is arranged in a horizontal direction and located above the second through hole 132. In order to connect another part of the feed element 14 and the filter component 20, one of the feed element 14 or the filter component 20 can be selectively extended along the thickness direction of the substrate 11 until it is connected to the other one. Of course, both can also be extended at the same time and the connection is completed in the through hole. There are no excessive limitations on this.

[0056] It is worth mentioning that in this embodiment, the signal flow direction is input from the filter component 20, and after passing through the filter component 20, it is conducted through the feed element 14 and the reflector 12, so as to excite the radiation patch 13 to radiate electromagnetic waves.

[0057] In this embodiment, the filter component 20 can be one filter or multiple filters. For example, as Figure 19 shown, when the filter component 20 is one filter, the filter is arranged on the substrate 11 according to the above method. The filter arranged in this way is arranged inside the electromagnetic shielding cavity 151. In this embodiment, the feed element 14 is also one. The filter is connected to a single feed element 14 and conducted with the reflector 12. The electromagnetic shielding cavity 151 can shield the interference electromagnetic waves existing outside to improve the filtering performance of the filter. And because the filter is integrally processed and formed with the substrate 11, the filter can be highly integrated with the antenna component 10 and the substrate 11. Such a setting makes the filter integrated antenna structure have high integration, high filtering and high radiation performance.

[0058] By setting the filtering integrated antenna structure 1 in the above manner, not only can the problem that it is difficult to highly integrate the filter component 20 and the antenna component 10 be solved, but also the problem that the performance deteriorates due to interference after the high integration of the filter component 20 and the antenna component 10 can be effectively solved.

[0059] In one embodiment, as Figures 1 to 4 shown, the filter component 20 includes two filters arranged at intervals in the horizontal direction, and both of the two filters are provided with connection ends 211; the reflector 12 has two vias 121, and the two vias 121 are respectively used for the connection ends 211 to pass through. The aperture of the via 121 is larger than the diameter of the connection end 211, and the connection section is arranged at intervals with the via 121; the feeding member 14 includes two sub-feeding members 14; both the first through hole 131 and the second through hole 132 are provided with two, and are respectively used for the two sub-feeding members 14 or the two sub-feeding members 14 and the two filters to pass through and be connected. In this embodiment, a differential filtering integrated antenna structure 1 is proposed. In this embodiment, the filter component is composed of two filters. In this embodiment, the filter component 20 includes two filters arranged at intervals in the horizontal direction in the electromagnetic shielding cavity 151. Among them, the two filters respectively have connection ends 211, and the connection ends 211 are mainly used for externally connecting signal wire bodies. To facilitate the connection of the two filters to the external signal wire bodies, in this embodiment, two vias 121 are opened on the reflector 12. The two vias 121 respectively correspond to the two connection ends 211 and are used for the two connection ends 211 to be accommodated or extend out of the substrate 11. It should be noted that the aperture of the via 121 is larger than the diameter of the connection section, so that when the connection end 211 is accommodated in the via 121 or passes through the via 121, it is arranged at intervals with the via 121, that is, arranged at intervals with the reflector 12. In this embodiment, the feeding member 14 as the feeding structure includes two sub-feeding members 14, and both the first through hole 131 and the second through hole 132 on the radiation patch 13 are provided with two. The two first through holes 131 are respectively used for a part of the two sub-feeding members 14 to pass through, and the two second through holes 132 are respectively used for the two sub-feeding members 14 or the ends of the two filters far from the connection ends 211 to extend out, so that the two filters are respectively connected to the reflector 12 through the two sub-feeding members 14 to excite the radiation patch 13 to radiate electromagnetic waves. In this embodiment, the two filters, the two vias 121, the two first through holes 131 and the second through holes 132, and the two sub-feeding members 14 are symmetrically arranged in the horizontal direction.

[0060] In one embodiment, the connection ends 211 of the two filters are respectively used to externally connect equal-amplitude differential signals with a 180° phase difference, so that the filter-integrated antenna structure performs differential feeding. In this embodiment, the equal-amplitude differential signals with a 180° phase difference are accessed from the connection ends 211 of the two filters, pass through the filters in the shielding cavity, pass through the radiation patch 13, and finally reach the reflector 12 to excite the radiation patch 13, thereby realizing differential feeding to achieve excellent performance such as the inherent high gain and low cross-polarization of the differential antenna. For example, as Figures 13 to 18 , the simulated and measured radiation patterns at 9.4 GHz, 9.8 GHz, and 10.4 GHz are respectively given, showing good unidirectional radiation. The cross-polarization levels in the simulated E-plane and H-plane are both lower than -40 dB, and the measured cross-polarization levels are both lower than -23 dB. The simulated and measured 3-dB beam widths are both greater than 77°, and the front-to-back ratio is less than 20 dB. Compared with the traditional patch antenna, the radiation patterns in the E-plane and H-plane are more symmetrical, and the cross-polarization level is improved.

[0061] In one embodiment, the filter assembly 20 adopts two identical double-layer coupled filters with a spacing of g2. When working, equal-amplitude differential signals with a 180-degree phase difference are applied to the connection ends 211 of the two filters. For example, as Figure 10 shows, in this embodiment, the S-parameters of the filter assembly 20 are shown. Its working center frequency is 9.8 GHz, and the bandwidth with S11 ≤ -10 dB is 11%. The return loss of the input port is better than 27 dB, the insertion loss is less than 0.6 dB, and the passband ripple is less than 0.2 dB. The low insertion loss also benefits in part from the shielding cavity effectively reducing the radiation loss and interference. The transmission zeros TZ1 to TZ5 are located at 7.6, 8.8, 11.5, 14.6, and 17.1 GHz, achieving high selectivity and excellent out-of-band rejection performance, and the out-of-band rejection bandwidth reaches 1.6f 0 .

[0062] In one embodiment, as Figure 11 shows, the spacing between the two filters is 0.3 to 0.7 mm. It should be emphasized that the excellent performance of the two filters also benefits from the reasonable selection of the above parameter g2. g2 represents the spacing between the two filters. To further illustrate this point, simulations are carried out for different g2 values, as Figure 11 shows. Four parameters are selected: g2 = 0.7, 0.5, 0.3, 0.1 mm. It can be observed that when g2 is too small, there is coupling between the two filters, resulting in poor filtering performance, manifested as a decrease in the right-side selectivity of the S-parameter S21. When g2 reaches 0.5 mm and continues to increase, the filtering performance tends to be stable.

[0063] In one embodiment, as Figure 1 andFigure 7 As shown, the feeding element 14 includes a feeding post 141 and a microstrip line 142 connected in sequence. A part of the feeding post 141 passes through the first through hole 131 and the substrate 11 and is electrically connected to the feeding point of the reflector 12. One end of the microstrip line 142 is connected to the feeding post 141, and the other end is connected to the filter assembly 20. The microstrip line 142 includes a first connection section and a second connection section connected in sequence, and the connection part of the first connection section and the second connection section is bent. In this embodiment, the feeding element 14 mainly includes the feeding post 141 and the microstrip line 142 connected in sequence. Among them, the feeding post 141 is a part in the above embodiment, and the microstrip line 142 is another part in the above embodiment. The feeding post 141 is mainly used to pass through the first through hole 131 and the substrate 11 and be electrically connected to the feeding point of the reflector 12, while one end of the microstrip line 142 is electrically connected to the feeding post 141, and the other end is located above the second through hole 132. In this embodiment, the microstrip line 142 includes a first connection section and a second connection section (not shown in the figure). Such a setting is to facilitate the laying of the plurality of metal posts 15 in the above embodiment to prevent the microstrip line 142 from interfering with the setting of the plurality of metal posts 15.

[0064] In one embodiment, one end of each metal post 15 is connected to the reflector 12, and the other end is connected to the radiation patch 13. The plurality of metal posts 15 and a part of the reflector 12 and a part of the radiation patch 13 enclose to form the electromagnetic shielding cavity 151.

[0065] In one embodiment, the diameter of the metal post 15 is D, and D satisfies D < 0.2λ g ; the spacing between two adjacent metal posts 15 is S, and S satisfies S ≤ 2D; where λ g is the guided wavelength with the center frequency in the preset frequency range.

[0066] It is worth noting that the preset frequency range is set in advance by the R & D personnel. In this embodiment, the preset frequency range is the X-band frequency range. According to the IEEE521-2002 standard, its frequency is between 8 GHz and 12 GHz.

[0067] In one embodiment, as Figure 5As shown, the substrate 11 includes a first dielectric layer 111, a second dielectric layer 112, a third dielectric layer 113, a fourth dielectric layer 114, a fifth dielectric layer 115, a sixth dielectric layer 116, and a seventh dielectric layer 117. Multiple dielectric layers are stacked to form eight wiring layers. The eight wiring layers are, from top to bottom, the first wiring layer, the second wiring layer, the third wiring layer, the fourth wiring layer, the fifth wiring layer, the sixth wiring layer, the seventh wiring layer, and the eighth wiring layer. The radiation patch 13 is disposed on the second wiring layer, the reflector 12 is disposed on the eighth wiring layer, the feeding member 14 is disposed on the first wiring layer, and the first dielectric layer 111 is located between the microstrip line 142 and the radiation patch 13. The number of substrates 11 is seven, and multiple substrates 11 are stacked. The substrates include a first dielectric layer 111, a second dielectric layer 112, a third dielectric layer 113, a fourth dielectric layer 114, a fifth dielectric layer 115, a sixth dielectric layer 116, and a seventh dielectric layer 117. Multiple substrates 11 are stacked to form eight wiring layers, namely the first wiring layer, the second wiring layer, the third wiring layer, the fourth wiring layer, the fifth wiring layer, the sixth wiring layer, the seventh wiring layer, and the eighth wiring layer (not shown in the figure). Among them, the first wiring layer to the seventh wiring layer are sequentially disposed above the first dielectric layer 111 to the seventh dielectric layer 117 along the direction from the second end to the first end of the substrate 11, and the eighth wiring layer is disposed below the seventh dielectric layer 117. Specifically, since the second dielectric layer 112, the fourth dielectric layer 114, and the sixth dielectric layer 116 are flexible substrates, the above wiring layers are disposed above and below the first dielectric layer 111, the third dielectric layer 113, the fifth dielectric layer 115, and the seventh dielectric layer 117. In this embodiment, the radiation patch 13 is disposed on the second wiring layer, that is, between the first dielectric layer 111 and the second dielectric layer 112. The reflecting portion is disposed on the eighth wiring layer, that is, below the seventh dielectric layer. A part of the feeding member 14 is disposed on the first wiring layer, that is, above the first dielectric layer 111. In this embodiment, the signal transmission line is input from the connection end 211 of the two filters, passes through the filter assembly 20 in the electromagnetic shielding cavity 151, passes through the radiation patch 13 to the feeding member 14, and finally reaches the reflector 12 through the feeding member 14 to excite the radiation patch 13, Figure 5 The arrow path of which is the direction of the electromagnetic energy flow.

[0068] In one embodiment, as Figure 3As shown, the filter component 20 includes a dual-mode resonator 23, an input transmission member 21, and an output transmission member 22. The dual-mode resonator 23 includes a first resonator member 231 and a second resonator member 232 in an up-and-down structure. The first resonator member 231 and the second resonator member 232 are connected by a connecting member. The input transmission member 21 is electrically coupled to the first end of the dual-mode resonator 23, and the output transmission member 22 is electrically coupled to the second end of the dual-mode resonator 23. The input transmission member 21 is disposed on the seventh dielectric plate 117 and sequentially passes through the seventh wiring layer and the eighth wiring layer along the direction from the first end to the second end. The output transmission member 22 is disposed on the sixth dielectric plate 116 and sequentially passes through the sixth wiring layer, the fifth wiring layer, the fourth wiring layer, the third wiring layer, the second wiring layer, and the first wiring layer along the direction from the second end to the first end. The first resonator member 231 and the second resonator member 232 are disposed on the opposite sides of any dielectric plate between the first dielectric plate 111 and the seventh dielectric plate 117 along the direction from the first end to the second end. In this embodiment, the dual-mode resonator 23 of the filter component 20 adopts a three-dimensional structure in an up-and-down structure. Compared with the traditional planar dual-mode resonator 23, the coupling between the source and the load and the mutual coupling between the up-and-down structures are introduced. Thus, additional transmission zeros are introduced, improving the selectivity and out-of-band rejection ability of the filter, and at the same time reducing the size of the filter component 20 to a certain extent. In this embodiment, as Figure 3 and Figure 5 shown, both the input transmission member 21 and the output transmission member 22 include a vertical feeding portion and a coupling portion. The vertical feeding portion extends along the direction from the first end to the second end, and the coupling portion is laid horizontally. The coupling portion of the input transmission member 21 is disposed on the seventh dielectric plate 117, and the vertical feeding portion sequentially passes through the seventh wiring layer and the eighth wiring layer along the direction from the first end to the second end. The coupling portion of the output transmission member 22 is disposed on the sixth dielectric plate, and the vertical feeding portion sequentially passes through the sixth wiring layer, the fifth wiring layer, the fourth wiring layer, the third wiring layer, the second wiring layer, and the first wiring layer along the direction from the second end to the first end. In this embodiment, the first resonator member 231 and the second resonator member 232 can be disposed on the opposite sides of any dielectric plate between the first dielectric plate 111 and the seventh dielectric plate 117 along the direction from the first end to the second end. For example, they can be disposed on the opposite sides of the sixth dielectric plate 116. The first resonator member 231 is disposed on the seventh wiring layer, and the second resonator member 232 is disposed on the sixth wiring layer. Or the first resonator member 231 is disposed on the sixth wiring layer, and the second resonator member 232 is disposed on the seventh wiring layer. Or, disposed on the opposite sides of the fifth dielectric plate 115. The first resonator member 231 is disposed on the fifth wiring layer, and the second resonator member 232 is disposed on the sixth wiring layer. Or the first resonator member 231 is disposed on the sixth wiring layer, and the second resonator member 232 is disposed on the fifth wiring layer. No excessive limitation is made thereto.

[0069] In one embodiment, the first dielectric plate 111, the third dielectric plate 113, the fifth dielectric plate 115, and the seventh dielectric plate 117 are Rogers RO4350B, and the second dielectric plate 112, the fourth dielectric plate 114, and the sixth dielectric plate 116 are Rogers RO4450F; the thickness of the first dielectric plate 111 is 0.168 mm, the thicknesses of the third dielectric plate 113, the fifth dielectric plate 115, and the seventh dielectric plate 117 are all 0.508 mm, and the thicknesses of the second dielectric plate 112, the fourth dielectric plate 114, and the sixth dielectric plate 116 are all 0.2 mm; and / or, the length and width of the substrate 11 are both 20 mm, and the height is 2.29 mm. In this embodiment, physical manufacturing is achieved by using multilayer PCB technology. The substrate 11 used is Rogers RO4350B and RO4450F, with relative dielectric constants of 3.66 and 3.52 respectively, and loss tangent values of 0.0037 and 0.004 respectively. More specifically, for Figure 5 the structure in, the substrates 11 Med1 to Med4 are Rogers RO4350B, and the substrates 11 PP1 to PP3 are Rogers RO4450F. The thickness of the first dielectric plate 111 is 0.168 mm, the thicknesses of the third dielectric plate 113, the fifth dielectric plate 115, and the seventh dielectric plate 117 are all 0.508 mm, the thicknesses of the second dielectric plate 112, the fourth dielectric plate 114, and the sixth dielectric plate 116 are all 0.2 mm; the length and width of the substrate 11 are both 20 mm, and the height is 2.29 mm. The length of the substrate 11 is Figure 1 LG1 in, the width is WG1, and the height is Figure 5 H1 in. The overall size of the patch antenna is designed with reference to 0.44λ g ×0.42λ g ×0.1λ g where λ g is the guided wavelength. The size parameters of the filter integrated antenna structure 1 are shown in the following table:

[0070]

[0071] In one embodiment, as Figure 8 shown, the performance of the antenna assembly 10 is given, including the reflection parameter S11 and the gain. It operates at a center frequency of 9.8 GHz, ranging from 9.1 to 10.5 GHz, and the bandwidth with S11 ≤ -10 dB is 14%. The in-band gain is flat, approximately 7.3 dBi. Figure 9The simulated radiation pattern at 9.8 GHz is shown, exhibiting good unidirectional radiation characteristics. The 3 dB beamwidth is greater than 77°, and the front-to-back ratio is better than 22 dB. Compared with traditional patch antennas, the E-plane and H-plane patterns are more symmetric. The cross-polarization level achieves better performance due to differential feeding, below -40 dB, and thus cannot be observed in the figure.

[0072] In one embodiment, the filter assembly 20 employs two identical double-layer coupled filters with a spacing of g2. During operation, equal-amplitude differential signals with a 180-degree phase difference are applied to the connection terminals of the filters. Figure 10 The S-parameters of the filter assembly 20 are shown. Its operating center frequency is 9.8 GHz, and the bandwidth with S11 ≤ -10 dB is 11%. The return loss of the input port is better than 27 dB, the insertion loss is less than 0.6 dB, and the passband ripple is less than 0.2 dB. The low insertion loss also benefits in part from the shielding cavity effectively reducing radiation loss and interference. The transmission zeros TZ1 to TZ5 are located at 7.6, 8.8, 11.5, 14.6, and 17.1 GHz, achieving high selectivity and excellent out-of-band rejection performance, and the out-of-band rejection bandwidth reaches 1.6f 0 。

[0073] In one embodiment, as Figure 12 The S-parameters and gain of the prototype simulation and measurement of the filter-integrated antenna structure 1 using the above embodiment are shown. The center frequency operates at 9.8 GHz. The measured in-band gain is approximately 6.4 dBi. Compared with the 7.3 dBi gain of the antenna assembly 10, the total loss of the filter insertion loss, interconnect loss, and measurement deviation is 0.9 dB. The frequencies of the five transmission zeros are in good agreement with the performance of the filter assembly 20, with excellent filtering selectivity and out-of-band rejection performance, and the out-of-band rejection bandwidth reaches 1.6f 0 。

[0074] Figures 13 to 18, the simulated and measured radiation patterns at 9.4 GHz, 9.8 GHz, and 10.4 GHz are given respectively, showing good unidirectional radiation. The cross-polarization levels in both the simulated E-plane and H-plane are lower than -40 dB, and those in the measured results are lower than -23 dB. The 3-dB beamwidths in both the simulation and measurement are greater than 77°, and the front-to-back ratio is less than 20 dB. Compared with traditional patch antennas, the radiation patterns in the E-plane and H-plane are more symmetric, and the cross-polarization levels are improved. These improvements indicate that the performance of the integrated differential-filter integrated antenna structure still maintains the superior performance of the antenna component 10 and the filter component 20 before integration. While achieving high integration and a compact size, it exhibits superior filtering performance (excellent port matching, high selectivity, wide stopband, low loss, etc.) and excellent radiation characteristics (high gain, unidirectional radiation, high symmetry, low cross-polarization level, low front-to-back ratio, wide beamwidth, etc.). We expect that with excellent filtering and antenna performance in such a compact structure, the proposed differential patch-filter integrated antenna design will have great potential for modern wireless communication systems (such as the sixth-generation (6G) mobile communication).

[0075] The above are only exemplary embodiments of the present invention, and thus do not limit the patent scope of the present invention. Any equivalent structural transformation made under the technical concept of the present invention by using the content of the specification and drawings of the present invention, or any direct / indirect application in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A filter integrated antenna structure, characterized in that: include: An antenna assembly, comprising a substrate, a radiation patch, a reflector, a feeder and a plurality of metal pillars, wherein the substrate has a first end and a second end opposite to each other, the reflector is arranged at the first end of the substrate, the radiation patch is arranged between the first end and the second end, a plurality of the metal pillars are arranged through the substrate at intervals from the second end to the first end to enclose an electromagnetic shielding cavity, the radiation patch has a first through hole and a second through hole, the feeder is arranged at the second end of the substrate, a part of the feeder is arranged through the first through hole in sequence from the second end to the first end, the substrate is connected to the reflector, another part of the feeder is arranged in the horizontal direction and is located above the second through hole, and the feeder is arranged at intervals from the radiation patch; A filter component is disposed in the electromagnetic shielding cavity, the filter component is spaced apart from the radiation patch, and one of the filter component and the feeder passes through the second through hole and is connected to the other.

2. The filtering integrated antenna structure according to claim 1, characterized in that: The filter assembly comprises two filters spaced apart in the horizontal direction, and both filters are provided with a connection end; The reflector has two via holes, the two via holes are respectively used for the connection ends to pass through, the aperture of the via holes is larger than the diameter of the connection ends, and the connection ends are spaced apart from the via holes; The feeder comprises two sub-feeders; There are two of the first through holes and two of the second through holes, which are respectively used for two of the sub-feeds or two of the sub-feeds and two of the filters to pass through and connect.

3. The filtering integrated antenna structure according to claim 2, characterized in that: The connection ends of the two filters are respectively used to externally connect equal-amplitude differential signals with a phase difference of 180°, so that the antenna component structure can be differentially fed.

4. The filtering integrated antenna structure according to claim 2, characterized in that: The distance between two filters is 0.3 to 0.7 mm.

5. The filtering integrated antenna structure according to claim 1, characterized in that: The feeding element comprises a feeding post and a microstrip line connected in sequence, a part of the feeding post passes through the first through hole and the substrate to be electrically connected to the feeding point of the reflector, one end of the microstrip line is connected to the feeding post, and the other end is connected to the filter component; The microstrip line comprises a first connecting section and a second connecting section which are connected in sequence, and a connection between the first connecting section and the second connecting section is bent.

6. The filtering integrated antenna structure according to claim 1, characterized in that: One end of each of the metal pillars is connected to the reflector plate, and the other end is connected to the radiation patch. A plurality of the metal pillars, part of the reflector plate and part of the radiation patch are enclosed to form the electromagnetic shielding cavity.

7. The filtering integrated antenna structure according to claim 6, characterized in that: The diameter of the metal column is D, and D satisfies D<0.2λ g ; The distance between two adjacent metal pillars is S, and S satisfies S≤2D; Among them, λ g is the wavelength of the waveguide whose center frequency is within the preset frequency range.

8. The filtering integrated antenna structure according to any one of claims 1 to 7, characterized in that: The substrate comprises a first dielectric plate, a second dielectric plate, a third dielectric plate, a fourth dielectric plate, a fifth dielectric plate, a sixth dielectric plate and a seventh dielectric plate, wherein the plurality of dielectric plates are stacked into eight wiring layers, wherein the eight wiring layers are respectively a first wiring layer, a second wiring layer, a third wiring layer, a fourth wiring layer, a fifth wiring layer, a sixth wiring layer, a seventh wiring layer and an eighth wiring layer from top to bottom, wherein the radiation patch is arranged on the second wiring layer, the reflection plate is arranged on the eighth wiring layer, the microstrip line of the feed element is arranged on the first wiring layer, and the first dielectric plate is located between the microstrip line of the feed element and the radiation patch.

9. The filtering integrated antenna structure according to claim 8, characterized in that: The filter component includes a dual-mode resonator, an input transmission element, and an output transmission element. The dual-mode resonator includes a first resonant component and a second resonant component in an upper and lower structure. The first resonant component and the second resonant component are connected via a connecting element. The input transmission element is electrically coupled to the first end of the dual-mode resonator, and the output transmission element is electrically coupled to the second end of the dual-mode resonator. The input transmission element is arranged on the seventh dielectric plate and sequentially passes through the seventh wiring layer and the eighth wiring layer along the direction from the first end to the second end. The output transmission element is arranged on the sixth dielectric plate and sequentially passes through the sixth wiring layer, the fifth wiring layer, the fourth wiring layer, the third wiring layer, the second wiring layer, and the first wiring layer along the direction from the second end to the first end. The first resonant component and the second resonant component are arranged on opposite sides of any dielectric plate between the first dielectric plate and the seventh dielectric plate along the direction from the first end to the second end.

10. The filtering integrated antenna structure according to claim 7, characterized in that: The first dielectric plate, the third dielectric plate, the fifth dielectric plate and the seventh dielectric plate are RogersRO4350B, the second dielectric plate, the fourth dielectric plate and the sixth dielectric plate are RogersRO4450F; the thickness of the first dielectric plate is 0.168 mm, the thickness of the third dielectric plate, the fifth dielectric plate and the seventh dielectric plate are all 0.508 mm, and the thickness of the second dielectric plate, the fourth dielectric plate and the sixth dielectric plate are all 0.2 mm; And / or, the length and width of the substrate are both 20 mm, and the height is 2.29 mm.

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