Spatial domain and frequency domain filtering antenna

Abstract

The invention discloses a spatial domain and frequency domain filtering antenna which comprises a feed structure, an SIW slot antenna structure and a dielectric lens structure. The SIW slot antenna structure is located above the feed structure, the SIW slot antenna structure is electrically connected with the feed structure, the SIW slot antenna structure is provided with an SIW cavity, a coupling metal layer located on the SIW cavity and a first metal patch located on the coupling metal layer, and a slot is formed in the coupling metal layer; the dielectric lens structure is located above the SIW slot antenna structure, the dielectric lens structure is provided with a cavity and a second metal patch located on the cavity, and the cavity and the second metal patch are used for restraining the electromagnetic waves radiated by the first metal patch to form a flat-topped wave beam. The antenna provided by the technical scheme of the invention not only realizes the filtering characteristic on the traditional frequency domain, but also realizes the filtering characteristic on the space domain of the H surface, and can meet the design requirements of multiple functions and integration.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and in particular to a spatial domain and frequency domain filtering antenna. Background Technology

[0002] In traditional wireless systems, antennas only function as electromagnetic radiation sources. Filtering unwanted electromagnetic signals requires a separate filter, which is somewhat cumbersome for modern wireless systems that prioritize integration and miniaturization. Compared to traditional antennas, filtered antennas integrate electromagnetic radiation and filtering functions, significantly improving the design margin of the RF front-end and perfectly aligning with current development trends. Furthermore, spatial domain filtered antennas (flat-top beam antennas) are widely used due to their stable and uniform electromagnetic radiation capabilities. Therefore, integrated spatial and frequency domain filtered antennas have enormous application potential for future wireless communication systems. Most existing filtered antenna designs focus only on frequency domain filtering characteristics, lacking designs that also consider spatial domain filtering properties.

[0003] In view of this, it is necessary to propose further improvements to the current filter antenna structure. Summary of the Invention

[0004] To solve at least one of the above-mentioned technical problems, the main objective of this invention is to provide a spatial domain and frequency domain filtering antenna.

[0005] To achieve the above objectives, one technical solution adopted by the present invention is: providing a spatial domain and frequency domain filtering antenna, comprising:

[0006] A power feeding structure for delivering radio frequency energy to be fed in;

[0007] The SIW slot antenna structure is located above the feed structure and is electrically connected to the feed structure to receive radio frequency energy fed by the feed structure. The SIW slot antenna structure has an SIW cavity, a coupling metal layer on the SIW cavity, and a first metal patch on the coupling metal layer. A slot is formed in the coupling metal layer. After radio frequency energy is fed into the SIW cavity, electromagnetic resonance is generated. Electromagnetic waves are coupled and radiated through the slot of the coupling metal layer, so that the first metal patch generates electromagnetic resonance and radiates electromagnetic waves.

[0008] A dielectric lens structure is located above a SIW slot antenna structure. The dielectric lens structure has a cavity and a second metal patch located on the cavity. The cavity and the second metal patch are used to constrain the electromagnetic waves radiated by the first metal patch to form a flat-top beam.

[0009] The gap is a U-shaped gap, and the U-shaped gap couples and radiates electromagnetic waves to form three radiation modes. The cavity includes a first cavity, a second cavity, and a third cavity. The second metal patch includes a first sub-patch corresponding to the first cavity, a second sub-patch corresponding to the second cavity, and a third sub-patch corresponding to the third cavity. The first sub-patch is located above the first cavity, the second sub-patch is located above the second cavity, and the third sub-patch is located above the third cavity.

[0010] The three radiation modes are respectively the left radiation null point, the main radiation, and the right radiation null point. The first cavity and the first sub-patch are used to constrain the electromagnetic waves radiated by the left radiation null point, the second cavity and the second sub-patch are used to constrain the electromagnetic waves radiated by the main radiation, and the third cavity and the third sub-patch are used to constrain the electromagnetic waves radiated by the right radiation null point.

[0011] The U-shaped gap consists of a central rectangle and smaller rectangles on either side of the central rectangle. The length, width, and depth of the central rectangle are 0.16λ-0.20λ, 0.01λ-0.03λ, and 0.0005λ-0.0015λ, respectively, while the length, width, and depth of the smaller rectangles on either side are 0.05λ-0.09λ, 0.05λ-0.09λ, and 0.0005λ-0.0015λ, respectively.

[0012] The length, width, and depth dimensions of the first cavity and the third cavity are 0.2λ-0.3λ, 0.2λ-0.3λ, and 0.3λ-0.7λ, respectively, and the length, width, and depth dimensions of the second cavity are 0.7λ-1.1λ, 0.1λ-0.5λ, and 0.3λ-0.7λ, respectively, where λ is the vacuum wavelength.

[0013] The SIW slot antenna structure further includes a second dielectric layer and a third dielectric layer. The lower surface of the second dielectric layer has a metal ground plane. The coupling metal layer is located on the upper surface of the second dielectric layer. The second dielectric layer has a plurality of first metal vias penetrating the second dielectric layer. The plurality of first metal vias connect the metal ground plane and the coupling metal layer. The SIW cavity is formed in the space enclosed by the metal ground plane, the first metal vias and the coupling metal layer. The SIW cavity has a stripline electrically connected to the feed structure.

[0014] The length, width, and depth dimensions of the SIW cavity are 0.86λ-0.90λ, 0.49λ-0.53λ, and 0.05λ-0.07λ, respectively. The length, width, and thickness dimensions of the stripline are 0.22λ-0.26λ, 0.02λ-0.03λ, and 0.0005λ-0.0015λ, respectively. The distance between the stripline and the coupling metal layer is 0.01λ, where λ is the vacuum wavelength.

[0015] The power supply structure is a first dielectric layer, and a metal pad is printed on the lower surface of the first dielectric layer. A plurality of second metal vias are provided in the middle of the first dielectric layer, and the plurality of second metal vias connect the metal pads and the metal ground plane. The metal pads have a power supply section in the middle, and the power supply section is electrically connected to the strip line through a metal conductor.

[0016] It also includes a plurality of third metal vias that pass through the first dielectric layer, the second dielectric layer and the third dielectric layer in sequence. There are at least two sets of the plurality of third metal vias. One set of third metal vias is located on the first side of the first dielectric layer, the second dielectric layer and the third dielectric layer, and the other set of third metal vias is located on the second side of the first dielectric layer, the second dielectric layer and the third dielectric layer. The first side and the second side are arranged opposite to each other.

[0017] The dielectric lens structure includes a fourth dielectric layer and a fifth dielectric layer. The first cavity, the second cavity, and the third cavity are respectively located in the fourth dielectric layer. The second cavity is located between the first cavity and the third cavity, and the occupied areas of the first cavity and the third cavity are respectively smaller than the occupied area of ​​the second cavity.

[0018] The first sub-patch, the second sub-patch, and the third sub-patch are located on the upper surface of the fifth dielectric layer. Each of the first sub-patch, the second sub-patch, and the third sub-patch includes multiple patch blocks. The patch blocks that make up the first sub-patch and the third sub-patch are arranged in a matrix, and the patch blocks that make up the second sub-patch are arranged in a row.

[0019] The length and width of the patch blocks in the first and third sub-patches are 0.08λ-0.12λ and 0.06λ-0.1λ, respectively, and the length and width of the patch blocks in the second sub-patches are 0.08λ-0.12λ and 0.08λ-0.12λ, respectively. The spacing between adjacent patch blocks is 0.005λ-0.015λ.

[0020] The dimensions of the first dielectric layer are 2.0λ-2.4λ, 0.5λ-0.9λ, and 0.005λ-0.015λ, respectively; the dimensions of the second dielectric layer are 2.0λ-2.4λ, 0.5λ-0.9λ, and 0.05λ-0.07λ, respectively; the dimensions of the third dielectric layer are 2.0λ-2.4λ, 0.5λ-0.9λ, and 0.03λ-0.05λ, respectively; the dimensions of the fourth dielectric layer are 2.0λ-2.4λ, 0.3λ-0.7λ, and 0.03λ-0.07λ, respectively; and the dimensions of the fifth dielectric layer are 2.0λ-2.4λ, 0.3λ-0.7λ, and 0.02λ-0.06λ, respectively.

[0021] The length, width and height of the first metal patch are 0.39λ-0.43λ, 0.205λ-0.225λ, and 0.0005λ-0.0015λ, respectively, where λ is the vacuum wavelength.

[0022] The technical solution of this invention mainly includes a feeding structure, a SIW slot antenna structure, and a dielectric lens structure. The feeding structure is used to feed in radio frequency energy. The SIW slot antenna structure has an SIW cavity, a coupling metal layer with slots, and a first metal patch. The SIW cavity receives the radio frequency energy fed in by the feeding structure and generates electromagnetic resonance. Then, through slot coupling, it radiates electromagnetic waves, causing the first metal patch to resonate, resulting in a better frequency filtering effect. The dielectric lens structure has a cavity and a second metal patch. The radiated electromagnetic waves are further constrained when passing through the cavity and the second metal patch, forming a flat-top beam and producing a good H-plane spatial filtering effect. In summary, this solution, based on the SIW slot antenna structure and combined with a dielectric lens, shapes the beam in the spatial domain, achieving filtering characteristics not only in the traditional frequency domain but also in the H-plane spatial domain, i.e., a flat-top beam. It has stable filtering and frequency selectivity over a wide bandwidth, meeting the design requirements of multifunctionality and integration. In addition, this antenna also has the advantages of simple structure and stable radiation pattern. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0024] Figure 1 This is an exploded schematic diagram of a spatial domain and frequency domain filtering antenna according to an embodiment of the present invention;

[0025] Figure 2 This is another exploded view of a spatial domain and frequency domain filtering antenna according to an embodiment of the present invention;

[0026] Figure 3a This is a schematic diagram of the coupling metal layer in a spatial domain and frequency domain filtering antenna according to an embodiment of the present invention;

[0027] Figure 3b This is a schematic diagram of the structure of the metal ground plane in a spatial domain and frequency domain filtered antenna according to an embodiment of the present invention;

[0028] Figure 4a This is a schematic diagram of the structure of the fifth dielectric layer in a spatial domain and frequency domain filtering antenna according to an embodiment of the present invention;

[0029] Figure 4bThis is a schematic diagram of the structure of the fourth dielectric layer in a spatial domain and frequency domain filtering antenna according to an embodiment of the present invention;

[0030] Figure 5 The diagram shows the S11 parameters and gain curves corresponding to the antenna of this invention.

[0031] Figure 6a , 6b And 6c are the antenna passband radiation patterns with center frequencies of 28GHz, 30GHz, and 32GHz respectively;

[0032] Figure 7 This is a spatial gain curve of the antenna of the present invention in the H-plane.

[0033] Label Explanation:

[0034] 100. Power supply structure:

[0035] 110. First dielectric layer; 111. Metal pad; 112. Second metal via; 113. Metal conductor; 114. Connector connector.

[0036] 200. SIW slot antenna structure:

[0037] 210, Second dielectric layer; 211, Metal ground plane; 212, Coupling metal layer; 2121, Gap; 213, First metal via; 214, Stripline; 215, SIW cavity; 220, Second dielectric layer; 221, First metal patch; 230, Third metal via.

[0038] 300. Dielectric lens structure:

[0039] 310. Fourth dielectric layer; 311. Cavity; 3111. First cavity; 3112. Second cavity; 3113. Third cavity; 320. Fifth dielectric layer; 321. Second metal patch; 3211. First sub-patch; 3212. Second sub-patch; 3213. Third sub-patch.

[0040] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0042] It should be noted that the descriptions involving "first," "second," etc., in this invention are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Furthermore, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0043] Unlike most existing filter antenna designs that only focus on frequency domain filtering characteristics and lack consideration for spatial domain filtering characteristics, this invention provides a spatial and frequency domain filtering antenna that achieves filtering characteristics not only in the traditional frequency domain but also in the H-plane spatial domain. The specific structure of this spatial and frequency domain filtering antenna is described in the following embodiment.

[0044] Please refer to Figures 1 to 4b , Figure 1 This is an exploded schematic diagram of a spatial domain and frequency domain filtering antenna according to an embodiment of the present invention; Figure 2 This is another exploded view of a spatial domain and frequency domain filtering antenna according to an embodiment of the present invention;

[0045] Figure 3a This is a schematic diagram of the coupling metal layer in a spatial domain and frequency domain filtering antenna according to an embodiment of the present invention;

[0046] Figure 3b This is a schematic diagram of the structure of the metal ground plane in a spatial domain and frequency domain filtered antenna according to an embodiment of the present invention; Figure 4a This is a schematic diagram of the structure of the fifth dielectric layer in a spatial domain and frequency domain filtering antenna according to an embodiment of the present invention; Figure 4b This is a schematic diagram of the structure of the fourth dielectric layer in a spatial domain and frequency domain filtering antenna according to an embodiment of the present invention; in this embodiment, the spatial domain and frequency domain filtering antenna includes:

[0047] A feed structure 100 is used to deliver the radio frequency (RF) energy to be fed in. The feed structure 100 is connected to an SMPS (RF coaxial power supply) via a connector 114 to receive the RF energy to be transmitted. The feed structure 100, the SIW slot antenna structure 200, and the dielectric lens structure 300 are arranged sequentially along the radiation direction of the antenna. Taking the illustration as an example, the feed structure 100 is located at the bottom layer, the SIW slot antenna structure 200 is located at the middle layer, and the dielectric lens structure 300 is located at the top layer.

[0048] A SIW (Integrated Dielectric Waveguide) slot antenna structure 200 is located above a feed structure 100 and is electrically connected to the feed structure 100. It receives radio frequency (RF) energy fed from the feed structure 100. The SIW slot antenna structure 200 has an SIW cavity 215, a coupling metal layer 212 on the SIW cavity 215, and a first metal patch 221 on the coupling metal layer 212. A slot 2121 is formed in the coupling metal layer 212. After RF energy is fed into the SIW cavity 215, electromagnetic resonance is generated, and electromagnetic waves are coupled and radiated through the slot 2121 of the coupling metal layer 212, causing the first metal patch 221 to generate electromagnetic resonance and radiate electromagnetic waves. The shape of the SIW cavity 215 is not limited to a rectangle; it can also be other polygonal, circular, or irregular shapes. A rectangle is preferred in this design. After receiving the radio frequency energy fed by the feeding structure 100, the SIW cavity 215 generates electromagnetic oscillations within the cavity. The oscillations then radiate electromagnetic waves through the slot 2121 in the coupling metal layer 212. The slot 2121 can be rectangular, or a U-shaped or H-shaped structure composed of multiple rectangles; in this design, a U-shape is preferred. The slot 2121 is located in the middle of the coupling metal layer 212. Due to the coupling effect of the slot 2121, the first metal patch 221 resonates, forming three radiation modes. Because the far-field radiation modes cancel each other out, independently adjustable radiation nulls are generated on both sides of the passband, resulting in better frequency filtering.

[0049] A dielectric lens structure 300 is located above the SIW slot antenna structure 200. The dielectric lens structure 300 has a cavity 311 and a second metal patch 321 located on the cavity 311. The cavity 311 and the second metal patch 321 are used to constrain the electromagnetic waves radiated by the first metal patch 221, forming a flat-top beam. A portion of the electromagnetic waves propagates in the long dielectric, causing the spatial beam in the zenith direction to become flatter. Due to the presence of the cavity 311, the radiated electromagnetic waves are further constrained when passing through the cavity 311 and the second metal patch 321, forming a flat-top beam and producing a good H-plane spatial filtering effect.

[0050] In a specific embodiment, the gap 2121 is a U-shaped gap 2121, and the U-shaped gap 2121 couples and radiates electromagnetic waves to form three radiation modes. The cavity 311 includes a first cavity 3111, a second cavity 3112, and a third cavity 3113. The second metal patch 321 includes a first sub-pattern 3211 corresponding to the first cavity 3111, a second sub-pattern 3212 corresponding to the second cavity 3112, and a third sub-pattern 3213 corresponding to the third cavity 3113. The first sub-pattern 3211 is located above the first cavity 3111, the second sub-pattern 3212 is located above the second cavity 3112, and the third sub-pattern 3213 is located above the third cavity 3113.

[0051] The three radiation modes are respectively the left radiation null point, the main radiation, and the right radiation null point. The first cavity 3111 and the first sub-pattern 3211 are used to constrain the electromagnetic waves radiated by the left radiation null point, the second cavity 3112 and the second sub-pattern 3212 are used to constrain the electromagnetic waves radiated by the main radiation, and the third cavity 3113 and the third sub-pattern 3213 are used to constrain the electromagnetic waves of the right radiation null point.

[0052] In this embodiment, the shapes of the first cavity 3111, the second cavity 3112, and the third cavity 3113 can be designed according to actual requirements. In this scheme, the shapes of the first cavity 3111, the second cavity 3112, and the third cavity 3113 are all rectangular. The first cavity 3111, the second cavity 3112, and the third cavity 3113 can be connected. The first sub-pattern 3211, the second sub-pattern 3212, and the third sub-pattern 3213 are set corresponding to the first cavity 3111, the second cavity 3112, and the third cavity 3113, and are used to adjust impedance matching and enhance radiation gain. Due to the mutual cancellation of the far field of the radiation mode, independently adjustable radiation nulls are generated on both sides of the passband.

[0053] In one specific embodiment, the U-shaped gap 2121 is divided into a central rectangle and smaller rectangles located on both sides of the central rectangle. The length, width, and depth of the central rectangle are 0.16λ-0.20λ, 0.01λ-0.03λ, and 0.0005λ-0.0015λ, respectively, and the length, width, and depth of the smaller rectangles on both sides are 0.05λ-0.09λ, 0.05λ-0.09λ, and 0.0005λ-0.0015λ, respectively.

[0054] The length, width, and depth dimensions of the first cavity 3111 and the third cavity 3113 are 0.2λ-0.3λ, 0.2λ-0.3λ, and 0.3λ-0.7λ, respectively, and the length, width, and depth dimensions of the second cavity 3112 are 0.7λ-1.1λ, 0.1λ-0.5λ, and 0.3λ-0.7λ, respectively, where λ is the vacuum wavelength.

[0055] Understandably, the specific dimensions of the U-shaped gap 2121, the first cavity 3111, the second cavity 3112, and the third cavity 3113 can be flexibly selected according to actual design requirements, and no restrictions are imposed here.

[0056] In one specific embodiment, the SIW slot antenna structure 200 further includes a second dielectric layer 210 and a third dielectric layer 220. The lower surface of the second dielectric layer 210 has a metal ground plane 211, and the coupling metal layer 212 is located on the upper surface of the second dielectric layer 210. The second dielectric layer 210 has a plurality of first metal vias 213 penetrating through it in the middle. The plurality of first metal vias 213 connect the metal ground plane 211 and the coupling metal layer 212. The SIW cavity 215 is formed in the space enclosed by the metal ground plane 211, the first metal vias 213, and the coupling metal layer 212. The SIW cavity 215 has a stripline 214 electrically connected to the feed structure 100. The plurality of first metal vias 213 form a rectangle. It should be noted that, for ease of coupling, a plurality of first metal vias 213 arranged in rows can be provided within the rectangle formed by the first metal vias 213 to divide the SIW cavity 215 into multiple small spaces, thereby improving the coupling effect. The first metal patch 221 is located at the middle position on the upper surface of the third dielectric layer 220, the metal ground plane 211 is located at the middle position on the lower surface of the second dielectric layer 210, and the coupling metal layer 212 is located at the middle position on the upper surface of the second dielectric layer 210. The stripline 214 can also be replaced with a microstrip line.

[0057] The excitation path of the main radiation resonant mode is cavity-coupled stripline 214, coupled to U-shaped slot 2121, and then coupled to the first metal patch 221. Therefore, the impedance of stripline 214 significantly affects the impedance matching of the main radiation resonant mode. The increased coupling path of stripline 214 makes it more difficult for out-of-band energy to be coupled to the metal patch, thus improving the out-of-band suppression level.

[0058] Specifically, the length, width, and depth dimensions of the SIW cavity 215 are 0.86λ-0.90λ, 0.49λ-0.53λ, and 0.05λ-0.07λ, respectively, and the length, width, and depth dimensions of the stripline 214 are 0.22λ-0.26λ, 0.02λ-0.03λ, and 0.0005λ-0.0015λ, respectively. The distance between the stripline 214 and the coupling metal layer 212 is 0.01λ, where λ is the vacuum wavelength.

[0059] It is understandable that the SIW cavity 215 in this solution is not limited to the above dimensions. The specific dimensions of the SIW cavity 215 can be flexibly selected according to the actual design requirements, and no restrictions are imposed here.

[0060] In one specific embodiment, the power supply structure 100 is a first dielectric layer 110. Metal pads 111 are printed on the lower surface of the first dielectric layer 110. Multiple second metal vias 112 penetrating the first dielectric layer 110 are disposed in the middle of the first dielectric layer 110. These second metal vias 112 connect the metal pads 111 to the metal ground plane 211. A power supply section is located in the middle of each metal pad 111, and this power supply section is electrically connected to the stripline 214 via a metal conductor 113. The metal pads 111 are fixed to the lower surface of the metal ground plane 211 by printing. The metal pads 111 are connected to the metal ground plane 211 via eight second metal vias 112. The number of second metal vias 112 can be varied, and their arrangement can be symmetrical. The metal conductor 113 can be replaced with a coaxial conductor. The metal conductor 113 is directly connected to the stripline 214, avoiding the metal ground plane 211, and is connected to the coupling metal layer 212.

[0061] In one specific embodiment, it further includes a plurality of third metal vias 230 that sequentially penetrate the first dielectric layer 110, the second dielectric layer 210, and the third dielectric layer 220. There are at least two sets of the plurality of third metal vias 230. One set of third metal vias 230 is located on the first side of the first dielectric layer 110, the second dielectric layer 210, and the third dielectric layer 220, and the other set of third metal vias 230 is located on the second side of the first dielectric layer 110, the second dielectric layer 210, and the third dielectric layer 220. The first side and the second side are disposed opposite to each other.

[0062] The third metal via 230 is designed to suppress sidelobes of the H-plane beam, thus reducing unnecessary electromagnetic radiation. Two rows of these vias can effectively reduce radiation at theta between 90 and 120 degrees. Theoretically, the smaller the spacing between adjacent third metal vias 230, the better the electromagnetic shielding and sidelobe suppression. However, the spacing and dimensions in this design are based on standard manufacturing processes. Therefore, a spacing of 0.75 mm between adjacent third vias is optimal, and a spacing of 3.35 mm between the third metal via 230 and the metal patch is also optimal.

[0063] In a specific embodiment, the dielectric lens structure 300 includes a fourth dielectric layer 310 and a fifth dielectric layer 320. The first cavity 3111, the second cavity 3112 and the third cavity 3113 are respectively located in the fourth dielectric layer 310. The second cavity 3112 is located between the first cavity 3111 and the third cavity 3111, and the occupied areas of the first cavity 3111 and the third cavity 3113 are respectively smaller than the occupied area of ​​the second cavity 3112.

[0064] The first sub-patch 3211, the second sub-patch 3212, and the third sub-patch 3213 are located on the upper surface of the fifth dielectric layer 320. Each of the first sub-patch 3211, the second sub-patch 3212, and the third sub-patch 3213 includes multiple patch blocks. The multiple patch blocks that make up the first sub-patch 3211 and the third sub-patch 3213 are arranged in a matrix, and the multiple patch blocks that make up the second sub-patch 3212 are arranged in a row.

[0065] The first sub-patch 3211 and the third sub-patch 3213 each include a 4*3 number of patch blocks, and the patch blocks are rectangular. The second sub-patch 3212 includes 4 patch blocks, and the patch blocks are square.

[0066] Specifically, the length and width dimensions of the patch blocks in the first sub-patch 3211 and the third sub-patch 3213 are 0.08λ-0.12λ and 0.06λ-0.1λ, respectively, and the length and width dimensions of the patch blocks in the second sub-patch 3212 are 0.08λ-0.12λ and 0.08λ-0.12λ, respectively. The spacing between adjacent patch blocks is 0.005λ-0.015λ.

[0067] Understandably, the size and spacing of the patch panels can be flexibly designed according to actual requirements, and there are no restrictions here.

[0068] Specifically, the length, width, and height dimensions of the first dielectric layer 110 are 2.0λ-2.4λ, 0.5λ-0.9λ, and 0.005λ-0.015λ, respectively; the length, width, and height dimensions of the second dielectric layer 210 are 2.0λ-2.4λ, 0.5λ-0.9λ, and 0.05λ-0.07λ, respectively; the length, width, and height dimensions of the third dielectric layer 220 are 2.0λ-2.4λ, 0.5λ-0.9λ, and 0.03λ-0.05λ, respectively; the length, width, and height dimensions of the fourth dielectric layer 310 are 2.0λ-2.4λ, 0.3λ-0.7λ, and 0.03λ-0.07λ, respectively; and the length, width, and height dimensions of the fifth dielectric layer 320 are 2.0λ-2.4λ, 0.3λ-0.7λ, and 0.02λ-0.06λ, respectively.

[0069] The length, width and height of the first metal patch 221 are 0.39λ-0.43λ, 0.205λ-0.225λ, and 0.0005λ-0.0015λ, respectively, where λ is the vacuum wavelength.

[0070] In this design, the first dielectric layer 110, the second dielectric layer 210, the third dielectric layer 220, the fourth dielectric layer 310, and the fifth dielectric layer 320 are all made of Ferro-A6M. The change in height of the third dielectric layer 220 means a change in the coupling electrical length. Good coupling effect can be produced in the range of 0.03λ-0.05λ, but the resonant frequency will change.

[0071] It should be noted that the entire antenna structure can be designed in a circular, elliptical, or triangular shape, etc.

[0072] This antenna design utilizes LTCC (Low Temperature Co-fired Ceramic) technology, which facilitates multi-layer stacking. It offers excellent filtering performance, a stable radiation pattern, a simple structure, and ease of integration, making it a promising candidate for important roles in integrated RF front-end systems. Examples of LTCC technologies include DuPont-951 and DuPont-9K7.

[0073] This antenna not only achieves filtering characteristics in the traditional frequency domain but also in the H-plane spatial domain (flat-top beam), exhibiting stable filtering and frequency selectivity over a wide bandwidth (27.054 GHz - 33.305 GHz). Furthermore, the antenna has a simple structure and a stable radiation pattern.

[0074] Please refer to Figures 5-7 , Figure 5 The diagram shows the S11 parameters and gain curves corresponding to the antenna of this invention. Figure 6a , 6b And 6c are the antenna passband radiation patterns with center frequencies of 28GHz, 30GHz, and 32GHz respectively; Figure 7 This is a spatial gain curve of the antenna of the present invention in the H-plane. Figure 5Figure 6 shows the S11 and gain performance curves for the antenna. The antenna's |S11| is better than -10 dB in the range of 27.05 to 33.3 GHz, and the antenna gain is better than 5.5 dBi in the passband. A radiation null is found at both 24.8 GHz and 36.2 GHz. The gain of the radiation null on the left side of the passband is lower than -19.8 dBi, and the gain of the radiation null on the right side of the passband is lower than -42.7 dBi. The out-of-band suppression level is also higher than 15 dBi. The radiation gain curve of the antenna element exhibits relatively steep roll-offs in the 25-27 GHz and 33-36 GHz frequency bands, giving the antenna high frequency selectivity. Figure 6 shows the radiation pattern in the passband. Stable end-fire patterns can be observed at 28 GHz, 30 GHz, and 32 GHz, with a sharp roll-off between 70 and 90 degrees Theta, demonstrating spatial filtering characteristics. Figure 7 This is a spatial gain curve of the antenna at various frequencies within the passband. The gain curve is consistent with the results shown in the radiation pattern. The gain is flat within the passband, and the spatial radiation null points are all within ±90 degrees. The out-of-band suppression level on the left side of the passband is 14-17.4dB, and on the right side it is 13.6-16.8dB. The 3dB beamwidth is over 60 degrees.

[0075] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A spatial domain and frequency domain filtering antenna, characterized in that, The spatial domain and frequency domain filtering antennas include: A power feeding structure for delivering radio frequency energy to be fed in; The SIW slot antenna structure is located above the feed structure and is electrically connected to the feed structure to receive radio frequency energy fed by the feed structure. The SIW slot antenna structure has an SIW cavity, a coupling metal layer on the SIW cavity, and a first metal patch on the coupling metal layer. A slot is formed in the coupling metal layer. After radio frequency energy is fed into the SIW cavity, electromagnetic resonance is generated. Electromagnetic waves are coupled and radiated through the slot of the coupling metal layer, so that the first metal patch generates electromagnetic resonance and radiates electromagnetic waves. A dielectric lens structure is located above a SIW slot antenna structure. The dielectric lens structure has a cavity and a second metal patch located on the cavity. The cavity and the second metal patch are used to constrain the electromagnetic waves radiated by the first metal patch to form a flat-top beam.

2. The spatial domain and frequency domain filtering antenna as described in claim 1, characterized in that, The gap is a U-shaped gap, and the U-shaped gap couples and radiates electromagnetic waves to form three radiation modes. The cavity includes a first cavity, a second cavity, and a third cavity. The second metal patch includes a first sub-pattern corresponding to the first cavity, a second sub-pattern corresponding to the second cavity, and a third sub-pattern corresponding to the third cavity. The first sub-pattern is located above the first cavity, the second sub-pattern is located above the second cavity, and the third sub-pattern is located above the third cavity. The three radiation modes are respectively the left radiation null point, the main radiation, and the right radiation null point. The first cavity and the first sub-patch are used to constrain the electromagnetic waves radiated by the left radiation null point, the second cavity and the second sub-patch are used to constrain the electromagnetic waves radiated by the main radiation, and the third cavity and the third sub-patch are used to constrain the electromagnetic waves radiated by the right radiation null point.

3. The spatial domain and frequency domain filtering antenna as described in claim 2, characterized in that, The U-shaped gap is divided into a central rectangle and smaller rectangles on both sides of the central rectangle. The length, width and depth of the central rectangle are 0.16λ-0.20λ, 0.01λ-0.03λ, and 0.0005λ-0.0015λ, respectively. The length, width and depth of the smaller rectangles on both sides are 0.05λ-0.09λ, 0.05λ-0.09λ, and 0.0005λ-0.0015λ, respectively. The length, width, and depth dimensions of the first and third cavities are 0.2λ-0.3λ, 0.2λ-0.3λ, and 0.3λ-0.7λ, respectively, while the length, width, and depth dimensions of the second cavity are 0.7λ-1.1λ, 0.1λ-0.5λ, and 0.3λ-0.7λ, respectively. Where λ is the vacuum wavelength.

4. The spatial domain and frequency domain filtering antenna as described in claim 2, characterized in that, The SIW slot antenna structure further includes a second dielectric layer and a third dielectric layer. The lower surface of the second dielectric layer has a metal ground plane. The coupling metal layer is located on the upper surface of the second dielectric layer. The second dielectric layer has a plurality of first metal vias penetrating the second dielectric layer. The plurality of first metal vias connect the metal ground plane and the coupling metal layer. The SIW cavity is formed in the space enclosed by the metal ground plane, the first metal vias and the coupling metal layer. The SIW cavity has a stripline electrically connected to the feed structure.

5. The spatial domain and frequency domain filtering antenna as described in claim 4, characterized in that, The length, width, and depth dimensions of the SIW cavity are 0.86λ-0.90λ, 0.49λ-0.53λ, and 0.05λ-0.07λ, respectively. The length, width, and thickness dimensions of the stripline are 0.22λ-0.26λ, 0.02λ-0.03λ, and 0.0005λ-0.0015λ, respectively. The distance between the stripline and the coupling metal layer is 0.01λ, where λ is the vacuum wavelength.

6. The spatial domain and frequency domain filtering antenna as described in claim 4, characterized in that, The power supply structure is a first dielectric layer. Metal pads are printed on the lower surface of the first dielectric layer. Multiple second metal vias are provided in the middle of the first dielectric layer, and the multiple second metal vias connect the metal pads and the metal ground plane. The metal pads have a power supply section in the middle, and the power supply section is electrically connected to the strip line through a metal conductor.

7. The spatial domain and frequency domain filtering antenna as described in claim 6, characterized in that, It also includes a plurality of third metal vias that pass through the first dielectric layer, the second dielectric layer and the third dielectric layer in sequence. There are at least two sets of the plurality of third metal vias. One set of third metal vias is located on the first side of the first dielectric layer, the second dielectric layer and the third dielectric layer, and the other set of third metal vias is located on the second side of the first dielectric layer, the second dielectric layer and the third dielectric layer. The first side and the second side are arranged opposite to each other.

8. The spatial domain and frequency domain filtering antenna as described in claim 7, characterized in that, The dielectric lens structure includes a fourth dielectric layer and a fifth dielectric layer. The first cavity, the second cavity, and the third cavity are respectively located in the fourth dielectric layer. The second cavity is located between the first cavity and the third cavity, and the occupied areas of the first cavity and the third cavity are respectively smaller than the occupied area of ​​the second cavity. The first sub-patch, the second sub-patch, and the third sub-patch are located on the upper surface of the fifth dielectric layer. Each of the first sub-patch, the second sub-patch, and the third sub-patch includes multiple patch blocks. The patch blocks that make up the first sub-patch and the third sub-patch are arranged in a matrix, and the patch blocks that make up the second sub-patch are arranged in a row.

9. The spatial domain and frequency domain filtering antenna as described in claim 8, characterized in that, The length and width dimensions of the patch blocks in the first and third sub-patches are 0.08λ-0.12λ and 0.06λ-0.1λ, respectively. The length and width dimensions of the patch blocks in the second sub-patches are 0.08λ-0.12λ and 0.08λ-0.12λ, respectively. The spacing between adjacent patch blocks is 0.005λ-0.015λ.

10. The spatial domain and frequency domain filtering antenna as described in claim 8, characterized in that, The length, width, and height dimensions of the first dielectric layer are 2.0λ-2.4λ, 0.5λ-0.9λ, and 0.005λ-0.015λ, respectively; the length, width, and height dimensions of the second dielectric layer are 2.0λ-2.4λ, 0.5λ-0.9λ, and 0.05λ-0.07λ, respectively; the length, width, and height dimensions of the third dielectric layer are 2.0λ-2.4λ, 0.5λ-0.9λ, and 0.03λ-0.05λ, respectively; the length, width, and height dimensions of the fourth dielectric layer are 2.0λ-2.4λ, 0.3λ-0.7λ, and 0.03λ-0.07λ, respectively; and the length, width, and height dimensions of the fifth dielectric layer are 2.0λ-2.4λ, 0.3λ-0.7λ, and 0.02λ-0.06λ, respectively. The length, width and height of the first metal patch are 0.39λ-0.43λ, 0.205λ-0.225λ, and 0.0005λ-0.0015λ, respectively, where λ is the vacuum wavelength.

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