Self-packaging filtering slot antenna based on folded substrate integrated waveguide cavity

Abstract

The invention discloses a self-packaging filtering slot antenna based on a folded substrate integrated waveguide cavity. The self-packaging filtering slot antenna comprises a first metal layer, a first dielectric substrate, a second metal layer, a second dielectric substrate, a third metal layer, a third dielectric substrate, a fourth metal layer, a fourth dielectric substrate and a fifth metal layer, the first metal layer is arranged on the upper surface of the first dielectric substrate; the second metal layer is arranged on the upper surface of the second dielectric substrate; the third metal layer is arranged on the upper surface of the third dielectric substrate; and the fourth metal layer and the fifth metal layer are respectively arranged on the upper surface and the lower surface of the fourth dielectric substrate. The novel filtering antenna provided by the invention has the characteristics of miniaturization, high selectivity, wide stop band and self-packaging, and can be well applied to the field of wireless communication systems.

Description

Technical Field

[0001] The invention relates to the technical field of wireless mobile communication, in particular to a self-packaging filtering slot antenna based on a folded substrate integrated waveguide cavity. Background Art

[0002] With the rapid development of wireless communication technology, RF front-end systems are developing towards high performance, high integration and miniaturization. Traditionally, traditional filtering antennas based on waveguide or microstrip technology often find it difficult to meet the requirements of miniaturization and integration. The emerging substrate integrated waveguide filter antenna has attracted widespread attention due to its low loss, low cost, high quality factor, high power capacity and integration capability. The present invention studies and designs a self-packaged filtering slot antenna based on a folded substrate integrated waveguide cavity, which has miniaturization, high selectivity, wide stopband characteristics and self-packaged characteristics, which is in line with actual engineering needs and has important theoretical and practical significance. Summary of the invention

[0003] Purpose of the invention: The purpose of the present invention is to design a self-packaged filtering slot antenna based on a folded substrate integrated waveguide cavity. This design proposes an innovative design method for a self-packaged filtering antenna, develops a new type of half-mode folded substrate integrated waveguide cavity, and designs the antenna in combination with the folded substrate integrated waveguide cavity, which significantly reduces the size and suppresses high-order modes; through the coupling aperture, cross-coupling is introduced to further improve the frequency selectivity of the filter; based on the self-packaged design, it not only ensures low loss, but also is very suitable for high-density integration application scenarios.

[0004] Technical solution: In order to achieve the above-mentioned purpose, the present invention proposes a self-packaged filtering slot antenna based on a folded substrate integrated waveguide cavity, the antenna comprising a first metal layer (100); a first dielectric substrate (200), the first dielectric substrate (200) being located on the lower surface of the first metal layer (100); a second metal layer (300), the second metal layer (300) being located on the lower surface of the first dielectric substrate (200); a second dielectric substrate (400), the second dielectric substrate (400) being located on the lower surface of the second metal layer (300); and a third metal layer (500). , the third metal layer (500) is located on the lower surface of the second dielectric substrate (400); the third dielectric substrate (600), the third dielectric substrate (600) is located on the lower surface of the third metal layer (500); the fourth metal layer (700), the fourth metal layer (700) is located on the lower surface of the third dielectric substrate (600); the fourth dielectric substrate (800), the fourth dielectric substrate (800) is located on the lower surface of the fourth metal layer (700); the fifth metal layer (900), the fifth metal layer (900) is located on the lower surface of the fourth dielectric substrate (800);

[0005] The first metal layer (100), the first dielectric substrate (200), the second metal layer (300), the second dielectric substrate (400) and the third metal layer (500) are arranged in a multi-layer form and are centrally stacked to form a folded substrate integrated waveguide cavity; the third metal layer (500), the third dielectric substrate (600), the fourth metal layer (700), the fourth dielectric substrate (800) and the fifth metal layer (900) are arranged in a multi-layer form and are centrally stacked to form a folded substrate integrated waveguide cavity.

[0006] Furthermore, a third coupling groove (701) is symmetrically arranged on one side of the fourth metal layer (700); a radiation groove (101) is etched on the first metal layer (100), and the radiation groove (101) is located in the center of the first metal layer (100); a first coupling groove (501) and a second coupling groove (502) are etched on the third metal layer (500), and the first coupling groove (501) and the second coupling groove (502) are located on the third metal layer (500). The first coupling slot (501) and the second coupling slot (502) are on the same straight line, and in terms of spatial position, the first coupling slot (501) and the second coupling slot (502) are biased towards the side opposite to the side where the third coupling slot (701) is located; a coplanar waveguide (901) for feeding is arranged at the corner of one side of the fifth metal layer (900), and in terms of spatial position, one side of the fifth metal layer (900) is opposite to the side where the third coupling slot (701) is located, and the coplanar waveguide (901) and the third coupling slot (701) are in the same direction in terms of spatial position.

[0007] Furthermore, a first metal through hole (201) arranged in a rectangular shape is provided at the center of the first dielectric substrate (200), and the radiation slot (101) is located in the center of the rectangle, and the first metal through hole (201) arranged in a rectangular shape passes through the first dielectric substrate (200) and the second dielectric substrate (400); a second metal through hole (601) arranged in a rectangular shape is provided at the center of the third dielectric substrate (600), and the second metal through hole (601) passes through the third dielectric substrate (600) and the fourth dielectric substrate (800).

[0008] Furthermore, the materials of the first dielectric substrate (200), the second dielectric substrate (400), the third dielectric substrate (600) and the fourth dielectric substrate (800) are F4B substrates.

[0009] Furthermore, the relative dielectric constant of the first dielectric substrate (200), the second dielectric substrate (400), the third dielectric substrate (600) and the fourth dielectric substrate (800) is 2.2 and the thickness is 1.5 mm.

[0010] Beneficial effects: Compared with the prior art, the technical solution of the present invention has the following beneficial technical effects:

[0011] (1) The present invention provides a self-packaged filter slot antenna design based on a folded substrate integrated waveguide cavity, which realizes multi-function and miniaturization. It has both the good radiation performance of a linear polarization antenna and the filtering performance of the filter device itself. It uses one device instead of the cascade of multiple devices, avoids the problem of large insertion loss, and realizes the integration of multiple functions. It also has the advantage of compact size.

[0012] (2) The present invention utilizes the second coupling slot (502) between the half-mode folded substrate integrated waveguide cavity and the folded substrate integrated waveguide cavity to introduce cross coupling, thereby obtaining a radiation zero point on the right side of the passband, and the position of the radiation zero point can be controlled by the second coupling slot (502). Therefore, the filtering antenna obtains good frequency selection characteristics.

[0013] (3) The present invention utilizes a half-mode folded substrate integrated waveguide cavity. Due to the presence of its long slot, the boundary conditions of the cavity change, resulting in TE 102 and TE 202 mode is no longer excited; when a radiation slot (101) is introduced at a suitable position of the top folded substrate integrated waveguide cavity, the TE 103 The conditions for mode excitation are no longer met. Therefore, an extremely wide stopband is achieved. From the subsequent simulation and test results, it can be seen that the -15dB bandwidth range is 2.53f o , where f o is the center frequency.

[0014] (4) The present invention is designed based on a folded substrate integrated waveguide cavity, which not only ensures low loss but also makes the antenna very suitable for high-density integrated self-packaging application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, so as to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, and the advantages and implementation methods of the present invention will be more obvious. The contents of the accompanying drawings are only used to illustrate and explain the present invention, but will not constitute any limitation to the present invention in any sense. In the accompanying drawings:

[0016] Figure 1 The three-dimensional structure schematic diagram of a self-packaged filtering slot antenna based on a folded substrate integrated waveguide cavity of the present invention.

[0017] Figure 2 The planar dimensions of a self-packaged filtering slot antenna based on a folded substrate integrated waveguide cavity of the present invention are shown in FIG. Figure 1 , including a first metal layer and a first dielectric substrate.

[0018] Figure 3The planar dimensions of a self-packaged filtering slot antenna based on a folded substrate integrated waveguide cavity of the present invention are shown in FIG. Figure 2 , including a second metal layer and a second dielectric substrate.

[0019] Figure 4 The planar dimensions of a self-packaged filtering slot antenna based on a folded substrate integrated waveguide cavity of the present invention are shown in FIG. Figure 3 , including a third metal layer and a third dielectric substrate.

[0020] Figure 5 The planar dimensions of a self-packaged filtering slot antenna based on a folded substrate integrated waveguide cavity of the present invention are shown in FIG. Figure 4 , including a fourth metal layer, a fourth dielectric substrate and a fifth metal layer.

[0021] Figure 6 The invention discloses an S parameter curve of a self-packaged filtering slot antenna based on a folded substrate integrated waveguide cavity.

[0022] Figure 7 The invention discloses a radiation pattern of a self-encapsulated filtering slot antenna based on a folded substrate integrated waveguide cavity. DETAILED DESCRIPTION

[0023] The embodiments of the present invention will be described below in conjunction with the accompanying drawings. The implementation modes shown in the accompanying drawings are only exemplary and are intended to explain the principles of the present invention, but are not intended to limit the scope of the present invention.

[0024] like Figure 1 As shown, the present invention provides a self-packaged filtering slot antenna based on a folded substrate integrated waveguide cavity, the antenna comprising a first metal layer (100); a first dielectric substrate (200), the first dielectric substrate (200) being located on the lower surface of the first metal layer (100); a second metal layer (300), the second metal layer (300) being located on the lower surface of the first dielectric substrate (200); a second dielectric substrate (400), the second dielectric substrate (400) being located on the lower surface of the second metal layer (300); and a third metal layer (500), the third dielectric substrate (500) being located on the lower surface of the second metal layer (300). The metal layer (500) is located on the lower surface of the second dielectric substrate (400); the third dielectric substrate (600), the third dielectric substrate (600) is located on the lower surface of the third metal layer (500); the fourth metal layer (700), the fourth metal layer (700) is located on the lower surface of the third dielectric substrate (600); the fourth dielectric substrate (800), the fourth dielectric substrate (800) is located on the lower surface of the fourth metal layer (700); the fifth metal layer (900), the fifth metal layer (900) is located on the lower surface of the fourth dielectric substrate (800);

[0025] The first metal layer (100), the first dielectric substrate (200), the second metal layer (300), the second dielectric substrate (400) and the third metal layer (500) are arranged in a multi-layer form and are centrally stacked to form a folded substrate integrated waveguide cavity; the third metal layer (500), the third dielectric substrate (600), the fourth metal layer (700), the fourth dielectric substrate (800) and the fifth metal layer (900) are arranged in a multi-layer form and are centrally stacked to form a folded substrate integrated waveguide cavity.

[0026] Furthermore, a third coupling groove (701) is symmetrically arranged on one side of the fourth metal layer (700); a radiation groove (101) is etched on the first metal layer (100), and the radiation groove (101) is located in the center of the first metal layer (100); a first coupling groove (501) and a second coupling groove (502) are etched on the third metal layer (500) with a spacing therebetween, and the first coupling groove (501) and the second coupling groove (502) are located on the third metal layer (500). Located in the same straight line, in terms of spatial position, the first coupling slot (501) and the second coupling slot (502) are biased towards the side opposite to the side where the third coupling slot (701) is located; a coplanar waveguide (901) for feeding is arranged at the corner of one side of the fifth metal layer (900), and in terms of spatial position, one side of the fifth metal layer (900) is opposite to the side where the third coupling slot (701) is located, and the coplanar waveguide (901) and the third coupling slot (701) are in the same direction in terms of spatial position.

[0027] Furthermore, a first metal through hole (201) arranged in a rectangular shape is provided at the center of the first dielectric substrate (200), and the radiation slot (101) is located in the center of the rectangle, and the first metal through hole (201) arranged in a rectangular shape passes through the first dielectric substrate (200) and the second dielectric substrate (400); a second metal through hole (601) arranged in a rectangular shape is provided at the center of the third dielectric substrate (600), and the second metal through hole (601) passes through the third dielectric substrate (600) and the fourth dielectric substrate (800).

[0028] Furthermore, the materials of the first dielectric substrate (200), the second dielectric substrate (400), the third dielectric substrate (600) and the fourth dielectric substrate (800) are F4B substrates.

[0029] Furthermore, the relative dielectric constant of the first dielectric substrate (200), the second dielectric substrate (400), the third dielectric substrate (600) and the fourth dielectric substrate (800) is 2.2 and the thickness is 1.5 mm.

[0030] In this design example, the characteristics of the folded substrate integrated waveguide cavity are utilized to achieve multifunctionality and miniaturization. It has both the good radiation performance of a linearly polarized antenna and the filtering performance of the filter device itself. One device is used instead of the cascade of multiple devices to avoid the problem of large insertion loss and achieve multifunctional integration. It also has the advantage of compact size. The second coupling slot (502) between the half-mode folded substrate integrated waveguide cavity and the folded substrate integrated waveguide cavity is used to introduce cross-coupling, and a zero point is obtained on the right side of the passband. At the same time, the position of the zero point can be controlled by the second coupling slot (502). Therefore, the filtering antenna obtains good frequency selection characteristics. The half-mode folded substrate integrated waveguide cavity is utilized. Due to the existence of its long slot, the boundary conditions of the cavity change, resulting in TE 102 and TE 202 The mode is no longer excited; when a radiation slot (101) is introduced at a suitable position of the top folded substrate integrated waveguide cavity, the TE 103 The conditions for mode excitation are no longer met. Therefore, an extremely wide stopband is achieved; the present invention is designed based on a folded substrate integrated waveguide cavity, which not only ensures low loss, but also makes the antenna very suitable for high-density integrated self-packaging application scenarios.

[0031] This design example achieves multifunctionality and miniaturization, and the final size is 0.75λg×0.37λg×0.12λg. Figure 1 to Figure 5 As shown, the specific dimensions are shown in Table 1 (unit: mm); among them, W, L 1， sw, sl, ds respectively represent the width and length of the substrate integrated cavity in the first metal layer (100) and the width, length and offset position of the radiation slot (101); df represents the distance from the upper edge of the second metal layer (300) to the upper edge of the substrate integrated cavity in the second dielectric substrate (400); L2 represents the length of the substrate integrated cavity of the third dielectric substrate (600); apw 1， apw 2， apl 1， apl 2， dap 1， dap2 respectively represents the size and spatial position of the first coupling slot (501) and the second coupling slot (502); gl represents the offset of the fourth metal layer (700) and the third coupling slot (701) about the y-direction symmetry axis, gl and gw represent the length and width of the third coupling slot (701); dp, g and l represent the specific dimensions of the coplanar waveguide (901).

[0032] Table 1

[0033]

[0034]

[0035] The actual test results of the present invention are close to the simulation results. The -10dB impedance bandwidth of the measured results is in the range of 4.09GHz to 4.19GHz (BW is 2.4%), the peak actual gain is 5dBi, the in-band efficiency exceeds 80%, and it is worth noting that the efficiency at the center frequency reaches 90%. Figure 6 The broadband response of the filter antenna is demonstrated. The designed filter antenna achieves a suppression level of 22.5dB in the upper near stopband, and the radiation zero point can be clearly observed on the right side of the passband, indicating the high selectivity of the invention. In addition, the 15dB stopband suppression is as high as 2.53f0, which has good out-of-band suppression performance. Figure 7 It is the radiation pattern of the filter antenna at the center frequency of 4.14Ghz, showing omnidirectional radiation characteristics and a cross-polarization level higher than 27dB, with good radiation performance.

[0036] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, chip, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, chip, article or device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, chip, article or device including the elements.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A self-packaged filtering slot antenna based on a folded substrate integrated waveguide cavity, characterized in that: The antenna comprises a first metal layer (100); a first dielectric substrate (200), wherein the first dielectric substrate (200) is located on the lower surface of the first metal layer (100); A second metal layer (300), the second metal layer (300) being located on the lower surface of the first dielectric substrate (200); A second dielectric substrate (400), the second dielectric substrate (400) being located on the lower surface of the second metal layer (300); A third metal layer (500), the third metal layer (500) being located on the lower surface of the second dielectric substrate (400); A third dielectric substrate (600), wherein the third dielectric substrate (600) is located on the lower surface of the third metal layer (500); A fourth metal layer (700), the fourth metal layer (700) being located on the lower surface of the three-medium substrate (600); A fourth dielectric substrate (800), the fourth dielectric substrate (800) being located on the lower surface of the fourth metal layer (700); a fifth metal layer (900), the fifth metal layer (900) being located on the lower surface of the fourth dielectric substrate (800); The first metal layer (100), the first dielectric substrate (200), the second metal layer (300), the second dielectric substrate (400) and the third metal layer (500) are arranged in a multi-layered and centrally stacked manner to form a folded substrate integrated waveguide cavity; The third metal layer (500), the third dielectric substrate (600), the fourth metal layer (700), the fourth dielectric substrate (800) and the fifth metal layer (900) are arranged in a multi-layered and centrally stacked manner to form a folded substrate integrated waveguide cavity.

2. A self-packaged filtering slot antenna based on a folded substrate integrated waveguide cavity according to claim 1, characterized in that: A third coupling slot (701) is symmetrically arranged on one side of the fourth metal layer (700); a radiation slot (101) is etched on the first metal layer (100), and the radiation slot (101) is located in the center of the first metal layer (100); a first coupling slot (501) and a second coupling slot (502) separated by a distance are etched on the third metal layer (500), and the first coupling slot (501) and the second coupling slot (502) are located at the same position on the third metal layer (500). A straight line, in terms of spatial position, the first coupling slot (501) and the second coupling slot (502) are biased towards the side opposite to the side where the third coupling slot (701) is located; a coplanar waveguide (901) for feeding is arranged at the corner of one side of the fifth metal layer (900), and in terms of spatial position, the above-mentioned one side of the fifth metal layer (900) is opposite to the side where the third coupling slot (701) is located, and the coplanar waveguide (901) and the third coupling slot (701) are in the same direction in terms of spatial position.

3. The self-packaged filtering slot antenna based on folded substrate integrated waveguide cavity according to claim 1, characterized in that: A first metal through hole (201) arranged in a rectangular shape is provided at the center of the first dielectric substrate (200), and the radiation slot (101) is located in the center of the rectangle, and the first metal through hole (201) arranged in a rectangular shape passes through the first dielectric substrate (200) and the second dielectric substrate (400); a second metal through hole (601) arranged in a rectangular shape is provided at the center of the third dielectric substrate (600), and the second metal through hole (601) passes through the third dielectric substrate (600) and the fourth dielectric substrate (800).

4. The self-packaged filtering slot antenna based on folded substrate integrated waveguide cavity according to claim 1, characterized in that: The materials of the first dielectric substrate (200), the second dielectric substrate (400), the third dielectric substrate (600) and the fourth dielectric substrate (800) are F4B substrates.

5. The self-packaged filtering slot antenna based on folded substrate integrated waveguide cavity according to claim 1, characterized in that: The relative dielectric constant of the first dielectric substrate (200), the second dielectric substrate (400), the third dielectric substrate (600) and the fourth dielectric substrate (800) is 2.2 and the thickness is 1.5 mm.

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