Light and thin substrate integrated waveguide antenna with high gain and oblique front detection
By optimizing the combined structure of the slot array and the coaxial core, the substrate integrated waveguide antenna is made thinner, lighter, higher gain, and lower loss. This solves the problem of limited gain improvement of traditional antennas in miniaturized devices and achieves high-precision detection and low-interference oblique front detection effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-04
- Publication Date
- 2026-03-27
AI Technical Summary
Traditional substrate-integrated waveguide antennas are difficult to achieve high gain, low loss, and low sidelobes due to limitations in thickness and volume. At the same time, the complex feeding network increases the antenna thickness and weight, limiting its application in miniaturized devices.
A lightweight, high-gain, oblique-front-probe substrate integrated waveguide antenna was designed. It adopts a combination structure of slot array and coaxial core. By optimizing the arrangement and geometry of the slot array, the main lobe gain exceeds 20dBi, the side lobe level is less than -13dB, the return loss is less than -43dB, and the main lobe direction has an angle of about 25° with the normal of the structure plane.
It achieves high detection accuracy and signal-to-noise ratio with extremely high energy efficiency, reduces clutter interference, and the antenna can be installed on the side surface of the vehicle for oblique front detection. It is small in size and light in weight, meeting the requirements of thin and light design.
Smart Images
Figure CN121748812A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to the technical field of millimeter wave radio detection, in particular to a light and thin high-gain oblique front detection substrate integrated waveguide antenna. BACKGROUND
[0002] The substrate integrated waveguide antenna simulates the electromagnetic constraint and transmission characteristics of a traditional rectangular waveguide by constructing a metalized via hole boundary on a dielectric substrate, and enables electromagnetic energy in the waveguide to be radiated to the outside space through a metal gap etched on the surface metal layer of the dielectric substrate, thereby realizing the function of the antenna. Such an antenna has the advantages of low profile, low cost and easy integration, and is widely used in the fields of vehicle-mounted millimeter wave detection, aerospace and satellite communication. With the continuous development of wireless devices and modules towards miniaturization and lightness, the traditional substrate integrated waveguide antenna needs to meet the performance requirements of high gain, low loss and low sidelobe under the limitation of extremely small thickness and volume.
[0003] In order to realize high gain, the substrate integrated waveguide antenna must use the form of a gap array, and existing designs mostly adopt a multi-path large array scheme. As the array size increases, a large-area feed network introduces higher feed loss and return loss, which limits the effect of gain improvement of the antenna. In addition, the complex feed network usually adopts a multi-layer metal waveguide coupling feed structure, which significantly increases the thickness of the antenna and increases the overall volume and weight. SUMMARY
[0004] In view of the above technical problems, the application provides a light and thin high-gain oblique front detection substrate integrated waveguide antenna, which has the advantages of light and thin structure, small volume and high gain. In addition, the antenna also has the characteristics of oblique detection, and can be installed on the side of a mobile vehicle to detect the front direction.
[0005] A light and thin high-gain oblique front detection substrate integrated waveguide antenna comprises, from top to bottom, a radiation gap array layer, a substrate integrated waveguide layer, a metal ground plate and a coaxial inner core electrically connected to the radiation gap array layer. The radiation gap array layer is a copper foil layer etched with a gap array, and comprises two parallel gap arrays. Each gap array comprises a plurality of gaps arranged at uniform intervals. The position of the gap array corresponds to a half-and-half waveguide cavity of the substrate integrated waveguide layer. The coaxial inner core vertically penetrates the substrate integrated waveguide layer and the metal ground plate from top to bottom and is insulated.
[0006] As a preferred form of the above technical solution, each of the slit arrays comprises 12 slits, the short side length of the slits is the same, the long side of the slits is arranged in parallel with the central axis of the one-to-two waveguide cavity, and the long side of each of the slits deviates from the central axis of the corresponding chamber in the one-to-two waveguide cavity by a distance, and one end of the slit array is electrically connected to the inner core of the coaxial line.
[0007] As a preferred form of the above technical solution, the distance between the two adjacent slits is 5.78 mm, the short side length of the slits is 0.3 mm, and each column of the slit array comprises, from left to right, a slit A, a slit B, a slit C, a slit D, a slit E, a slit F, a slit G, a slit H, a slit I, a slit J, a slit K, and a slit L,
[0008] The long side length of the slit A is 3.058 mm, and it deviates from the central axis of the waveguide by -0.060 mm;
[0009] The long side length of the slit B is 3.061 mm, and it deviates from the central axis of the waveguide by 0.070 mm;
[0010] The long side length of the slit C is 3.067 mm, and it deviates from the central axis of the waveguide by -0.104 mm;
[0011] The long side length of the slit D is 3.074 mm, and it deviates from the central axis of the waveguide by 0.149 mm;
[0012] The long side length of the slit E is 3.088 mm, and it deviates from the central axis of the waveguide by -0.199 mm;
[0013] The long side length of the slit F is 3.110 mm, and it deviates from the central axis of the waveguide by 0.243 mm;
[0014] The long side length of the slit G is 3.141 mm, and it deviates from the central axis of the waveguide by -0.282 mm;
[0015] The long side length of the slit H is 3.176 mm, and it deviates from the central axis of the waveguide by 0.313 mm;
[0016] The long side length of the slit I is 3.177 mm, and it deviates from the central axis of the waveguide by -0.313 mm;
[0017] The long side length of the slit J is 3.126 mm, and it deviates from the central axis of the waveguide by 0.266 mm;
[0018] The long side length of the slit K is 3.098 mm, and it deviates from the central axis of the waveguide by -0.223 mm;
[0019] The long side length of the slit L is 3.102 mm, and it deviates from the central axis of the waveguide by 0.070 mm,
[0020] wherein a positive number is offset upwards from the waveguide central axis, and a negative number is offset downwards from the waveguide central axis.
[0021] As a preferred form of the above technical solution, the substrate integrated waveguide layer further comprises a dielectric substrate and an electromagnetic field partitioning column, and the one-to-two waveguide cavity is a cavity enclosed by the electromagnetic field partitioning column inside the dielectric substrate.
[0022] As a preferred form of the above technical solution, the diameter of the electromagnetic field partitioning column is 0.4 mm.
[0023] As a preferred form of the above technical solution, the coaxial inner core comprises a coaxially arranged metal inner core and an outer insulating dielectric layer, and the metal inner core sequentially passes through the metal ground plate and the substrate integrated waveguide layer from bottom to top and is electrically connected to the top of the radiating slot array layer.
[0024] As a preferred form of the above technical solution, the radiating slot array layer, the electromagnetic field partitioning column, the metal ground plate and the metal inner core are all made of copper, the dielectric substrate is made of Rogers RT5880 material, and the outer insulating dielectric layer is made of polytetrafluoroethylene.
[0025] The present application has the following advantages:
[0026] By optimizing and specifically matching the arrangement mode and geometric size of the two rows of slot arrays, the substrate integrated waveguide antenna has a main lobe gain of more than 20 dBi, a side lobe level of less than -13 dB and a return loss of less than -43 dB, while being thin and light. The antenna can work under extremely high energy efficiency conditions and obtain extremely high detection accuracy and signal-to-noise ratio in the main lobe direction, and is not easily disturbed by clutter from other directions. In addition, by optimizing the design of the slot array spacing, the main lobe direction of the substrate integrated waveguide antenna has an angle of about 25° with the normal of the structural plane, so that the antenna can be installed on the side surface of the carrier and detect the oblique front or oblique rear of the carrier. BRIEF DESCRIPTION OF DRAWINGS
[0027] Figure 1 FIG. 1 is a structural schematic diagram of the present application.
[0028] Figure 2 FIG. 2 is an exploded view of the present application.
[0029] Figure 3 FIG. 3 is a top view of the radiating slot array layer.
[0030] Figure 4 FIG. 4 is a sectional view of the present application.
[0031] Figure 5 FIG. 5 is a top view of the substrate integrated waveguide layer.
[0032] Figure 6 is the three-dimensional far-field radiation pattern of the antenna obtained by simulation from CST Microwave Studio.
[0033] Figure 7 is the return loss S11 diagram at the port obtained by simulation from CST Microwave Studio.
[0034] Figure 8 is the two-dimensional far-field pattern on the antenna elevation plane of the present application at 3 typical frequency points (35.2, 35.4 and 35.6 GHz) obtained by simulation from CST Microwave Studio.
[0035] The reference signs are as follows: 1-radiation slot array layer, 101-slot array, 101a-slot A, 101b-slot B, 101c-slot C, 101d-slot D, 101e-slot E, 101f-slot F, 101g-slot G, 101h-slot H, 101i-slot I, 101j-slot J, 101k-slot K, 101l-slot L, 2-substrate integrated waveguide layer, 201-one-to-two waveguide cavity, 202-dielectric substrate, 203-electromagnetic field partition column, 3-metal floor, 4-coaxial inner core, 401-metal inner core, 402-outer insulating dielectric layer. DETAILED DESCRIPTION
[0036] The technical solutions of the present application will be described clearly and completely below in combination with the drawings of the present application. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without making creative efforts fall within the scope of protection of the present application.
[0037] As Figures 1 to 5 The thin and light high-gain oblique front detection substrate integrated waveguide antenna comprises, from top to bottom, a radiation slot array layer 1, a substrate integrated waveguide layer 2, a metal floor 3 and a coaxial inner core 4 electrically connected with the radiation slot array layer 1. The radiation slot array layer 1 is a copper foil layer etched with a slot array, comprising two parallel slot arrays 101. Each slot array 101 comprises a plurality of slots arranged at uniform intervals. The slot array 101 is arranged in correspondence with a one-to-two waveguide cavity 201 of the substrate integrated waveguide layer 2. The coaxial inner core 4 vertically passes through the substrate integrated waveguide layer 2 and the metal floor 3 from top to bottom and is insulatively arranged.
[0038] In the embodiment, each of the slit arrays 101 columns includes 12 slits, the short side length of the slits is the same, the long side of the slits is arranged in parallel with the central axis of the one-to-two waveguide cavity 201, and the long side of each of the slits deviates from the central axis of the corresponding chamber in the one-to-two waveguide cavity 201 by a distance, and one end of the slit array is electrically connected with the coaxial inner core 4.
[0039] In the embodiment, the distance between the adjacent two slits is 5.78mm, the short side length of the slits is 0.3mm, and each of the slit arrays 101 columns includes, from left to right, a slit A101a, a slit B101b, a slit C101c, a slit D101d, a slit E101e, a slit F101f, a slit G101g, a slit H101h, a slit I101i, a slit J101j, a slit K101k, and a slit L101l.
[0040] The long side length of the slit A101a is 3.058mm, and deviates from the waveguide center axis by -0.060mm.
[0041] The long side length of the slit B101b is 3.061mm, and deviates from the waveguide center axis by 0.070mm.
[0042] The long side length of the slit C101c is 3.067mm, and deviates from the waveguide center axis by -0.104mm.
[0043] The long side length of the slit D101d is 3.074mm, and deviates from the waveguide center axis by 0.149mm.
[0044] The long side length of the slit E101e is 3.088mm, and deviates from the waveguide center axis by -0.199mm.
[0045] The long side length of the slit F101f is 3.110mm, and deviates from the waveguide center axis by 0.243mm.
[0046] The long side length of the slit G101g is 3.141mm, and deviates from the waveguide center axis by -0.282mm.
[0047] The long side length of the slit H101h is 3.176mm, and deviates from the waveguide center axis by 0.313mm.
[0048] The long side length of the slit I101i is 3.177mm, and deviates from the waveguide center axis by -0.313mm.
[0049] The long side length of the slit J101j is 3.126mm, and deviates from the waveguide center axis by 0.266mm.
[0050] The long side length of the gap K101k is 3.098 mm, and the gap deviates from the central axis of the waveguide by -0.223 mm;
[0051] The long side length of the gap L101l is 3.102 mm, and the gap deviates from the central axis of the waveguide by 0.070 mm,
[0052] Wherein, the positive number is offset upwards to the central axis of the waveguide, and the negative number is offset downwards to the central axis of the waveguide.
[0053] In the embodiment, the substrate integrated waveguide layer 2 further comprises a dielectric substrate 202 and an electromagnetic field partitioning column 203, and the one-to-two waveguide cavity 201 is a cavity enclosed by the electromagnetic field partitioning column 203 inside the dielectric substrate 202.
[0054] In the embodiment, the diameter of the electromagnetic field partitioning column 203 is 0.4 mm.
[0055] In the embodiment, the coaxial line inner core 4 comprises a coaxially arranged metal inner core 401 and an outer insulating dielectric layer 402, the metal inner core 401 sequentially passes through the metal ground plate 3 and the substrate integrated waveguide layer 4 from bottom to top, and the top is electrically connected with the radiating gap array layer 1.
[0056] In the embodiment, the radiating gap array layer 1, the electromagnetic field partitioning column 203, the metal ground plate 3 and the metal inner core 401 are all made of copper, the dielectric substrate 502 is made of Rogers RT5880 material, and the outer insulating dielectric layer 402 is made of polytetrafluoroethylene.
[0057] Specifically, Figure 2 The metal ground plate 3 and the coaxial line inner core 4 together form a coaxial line port for feeding microwave power into the antenna, the microwave power enters the one-to-two waveguide cavity 201, is shunted into the two waveguides by the electromagnetic field partitioning column 203, sequentially passes through the gap A101a, the gap B101b, the gap C101c, the gap D101d, the gap E101e, the gap F101f, the gap G101g, the gap H101h, the gap I101i, the gap J101j, the gap K101k and the gap L101l, and is radiated into space. The same gap columns on the two waveguides play a role in radiation convergence, improving the antenna gain. The geometric sizes and axial deviation distances of the 12 gaps are optimized to match the equivalent impedances on the propagation routes, achieving minimum return loss and low sidelobe level. The three-dimensional far-field radiation pattern of the antenna obtained by simulation of the CST Microwave Studio is shown in Figure 6 .
[0058] The return loss S11 at the port obtained by simulation of the CST Microwave Studio is shown inFigure 7 The minimum return loss is <-43 dB by optimizing the structure size of the slot array, the half-wave waveguide and the electromagnetic split post, and by S11 <-15 dB in the frequency range of 35-35.7 GHz.
[0059] The two-dimensional far-field patterns of the antenna in the elevation plane of the application at three typical frequency points (35.2, 35.4 and 35.6 GHz) are simulated by CST Microwave Studio and shown in FIG. 3. Figure 8 At each frequency point, the main lobe magnitude of the antenna pattern is more than 20 dBi, and the main lobe direction is 25-26° deviated from the normal direction. In addition, the side lobe level at each frequency point is less than -13 dB, so it is not easy to be disturbed by clutter outside the detection direction. The above results show that the application has high gain and low side lobe characteristics in the working frequency range, and the return loss is very low. The overall length, width and height of the antenna are only 88.5 mm*16 mm*3.16 mm, and the weight is not more than 40 g.
[0060] The above is only the preferred embodiment of the application and is not used to limit the application. For those skilled in the art, the application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the application shall be included in the protection scope of the application.
Claims
1. A lightweight, high-gain, oblique-front detection substrate integrated waveguide antenna, characterized in that: The device comprises, from top to bottom, a radiating slot array layer, a substrate integrated waveguide layer, a metal ground plane, and a coaxial inner core electrically connected to the radiating slot array layer. The radiating slot array layer is a copper foil layer etched with slot arrays and includes two parallel slot arrays. Each slot array includes multiple slots evenly spaced. The positions of the slot arrays correspond to the one-to-two waveguide cavities of the substrate integrated waveguide layer. The coaxial inner core passes vertically from top to bottom through the substrate integrated waveguide layer and the metal ground plane and is insulated from top to bottom.
2. The thin and light high-gain oblique-front detection substrate integrated waveguide antenna according to claim 1, characterized in that: Each of the slot arrays includes 12 slots, the short sides of which are of equal length, the long sides of which are parallel to the central axis of the split waveguide cavity, and the long side of each slot is offset from the central axis of the corresponding chamber in the split waveguide cavity by a certain distance. One end of the slot array is electrically connected to the inner core of the coaxial line.
3. The thin and light high-gain oblique-front detection substrate integrated waveguide antenna according to claim 2, characterized in that: The distance between two adjacent gaps is 5.78 mm, and the shorter side of each gap is 0.3 mm. Each column of the gap array includes gap A, gap B, gap C, gap D, gap E, gap F, gap G, gap H, gap I, gap J, gap K, and gap L arranged sequentially from left to right. The long side of the slit A is 3.058 mm long and deviates from the central axis of the waveguide by -0.060 mm. The long side of the slit B is 3.061 mm long and deviates from the central axis of the waveguide by 0.070 mm. The long side of the slit C is 3.067 mm long and deviates from the central axis of the waveguide by -0.104 mm. The long side of the slit D is 3.074 mm long and deviates from the central axis of the waveguide by 0.149 mm. The long side of the slit E is 3.088 mm long and deviates from the central axis of the waveguide by -0.199 mm. The long side of the slit F is 3.110 mm long and deviates from the central axis of the waveguide by 0.243 mm. The long side of the slit G is 3.141 mm long and deviates from the central axis of the waveguide by -0.282 mm. The long side of the slit H is 3.176 mm long and deviates from the central axis of the waveguide by 0.313 mm. The long side of the slit I is 3.177 mm long and deviates from the central axis of the waveguide by -0.313 mm. The long side of the slit J is 3.126 mm long and deviates from the central axis of the waveguide by 0.266 mm. The long side of the slit K is 3.098 mm long and deviates from the central axis of the waveguide by -0.223 mm. The long side of the slit L is 3.102 mm long and deviates from the central axis of the waveguide by 0.070 mm. Positive numbers represent an upward offset from the waveguide's central axis, while negative numbers represent a downward offset from the waveguide's central axis.
4. The thin and light high-gain oblique front detection substrate integrated waveguide antenna according to claim 1, characterized in that: The substrate integrated waveguide layer also includes a dielectric substrate and electromagnetic field dividing pillars. The one-to-two waveguide cavity is a cavity formed inside the dielectric substrate by the electromagnetic field dividing pillars.
5. A thin, lightweight, high-gain oblique-front detection substrate integrated waveguide antenna according to claim 4, characterized in that: The diameter of the electromagnetic field dividing column is 0.4 mm.
6. The thin and light high-gain oblique-front detection substrate integrated waveguide antenna according to claim 4, characterized in that: The coaxial inner core includes a coaxially arranged metal inner core and an outer insulating dielectric layer. The metal inner core passes through the metal ground plane and the substrate integrated waveguide layer from bottom to top, and its top is electrically connected to the radiation slot array layer.
7. A lightweight, high-gain, oblique-front detection substrate integrated waveguide antenna according to claim 6, characterized in that: The radiating slot array layer, electromagnetic field dividing pillar, metal floor and metal core are all made of copper, the dielectric substrate is made of Rogers RT5880 material, and the outer insulating dielectric layer is made of polytetrafluoroethylene.