Low profile single-layer broadband microstrip patch antenna, device and radar detection system

Abstract

The application discloses a low-profile single-layer broadband microstrip patch antenna, equipment and a radar detection system, and relates to the technical field of antennas.The technical scheme points of the application are as follows: a dielectric substrate; a driving patch arranged on the dielectric substrate and fed by a coaxial probe; two parasitic patches symmetrically arranged on the two sides of the driving patch; and two symmetric coupling branches led out from the open end of the driving patch and respectively capacitively coupled to the two parasitic patches; wherein the working wavelength of the driving patch and the parasitic patch is configured as one-half of the waveguide wavelength, the double-mode excitation is realized through the capacitive coupling of the coupling branches, and the broadband antenna structure is formed.The application leads out two coupling branches near the open end of the driving patch, respectively capacitively couples the left and right parasitic patches, and symmetrically arranges the parasitic patches, so that the inductive impedance of the driving patch can be compensated, the resonant frequencies of the driving patch and the parasitic patch are adjusted together, and the double-mode of the driving patch and the parasitic patch forms a broadband.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and more specifically, to a low-profile single-layer broadband microstrip patch antenna, device, and radar detection system. Background Technology

[0002] Microstrip patch antennas are commonly used antennas, and their planar and low-profile characteristics make them widely applicable. To reduce costs, it's often desirable to minimize the number of PCB laminations; the optimal low-cost approach is zero laminations and single-layer fabrication. Under these conditions, to improve bandwidth, the classic approach is to use E-patch antennas or U-slot patches. Both E-patch and U-slot patch antennas are single-line polarized and use dual-mode excitation to achieve broadband performance. For example, an E-patch antenna achieves dual-mode performance by exciting odd and even modes, and then placing the resonant frequencies of the two modes close together to create broadband. Similarly, a U-slot patch antenna achieves dual-mode performance by etching slots to create two current paths on the patch antenna, and then placing the resonant frequencies of the two modes close together to create broadband. Both schemes use coaxial probe feeding, making them feasible low-cost solutions.

[0003] However, both E-type patch antennas and U-slot patch antennas require relatively large dimensions; the typical size of an antenna element is [missing information]. Furthermore, cross-polarization is poor when the H-plane deviates from the main beam angle by 45° or more. Typical values ​​for E-type patch antennas are greater than -3dB, and for U-slot patch antennas are greater than 2dB. Cross-polarization gains are higher than the main polarization above 45°. (Reference) Figure 1 and Figure 2 Furthermore, due to the complex coupling between the two modes in the broadband U-slot, it is difficult to accurately align the resonant frequencies of the two modes, which makes bandwidth optimization difficult and affects the stability of antenna performance.

[0004] Therefore, researching and designing a low-profile single-layer broadband microstrip patch antenna, device, and radar detection system that can overcome the above-mentioned defects is a problem that we urgently need to solve. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a low-profile single-layer broadband microstrip patch antenna, device, and radar detection system. Two symmetrical coupling stubs are led out near the open end of the driving patch to capacitively couple the parasitic patches on the left and right sides, respectively. The parasitic patches are symmetrically placed, which can compensate for the inductive impedance of the driving patch. This allows the resonant frequencies of the driving patch and the parasitic patch to be tuned together, thereby achieving broadband dual-mode formation of the driving patch and the parasitic patch.

[0006] The above-mentioned technical objective of the present invention is achieved through the following technical solution:

[0007] In a first aspect, a low-profile single-layer broadband microstrip patch antenna is provided, comprising:

[0008] Dielectric substrate;

[0009] A drive patch is disposed on the dielectric substrate and fed through a coaxial probe;

[0010] Two parasitic patches are symmetrically arranged on both sides of the driving patch;

[0011] And two symmetrical coupling stubs, which are led out from the open end of the driving patch and capacitively coupled to the two parasitic patches respectively;

[0012] The driving patch and the parasitic patch are configured to operate at half the waveguide wavelength, and dual-mode excitation is achieved through capacitive coupling of the coupling stubs to form a broadband antenna structure.

[0013] Furthermore, the driving patch and the parasitic patch are configured in rectangular, circular, or elliptical shapes.

[0014] Furthermore, when the driving patch and the parasitic patch are circular or elliptical in shape, the coupling branch is adapted to be arc-shaped to maintain the capacitive coupling strength between the driving patch and the parasitic patch.

[0015] Furthermore, the driving patch and the parasitic patch are configured in a semi-circular or semi-elliptical shape.

[0016] Furthermore, the coupling stub is configured in an arc shape for coupling with the arc portion of a semicircle or semiellipse.

[0017] Furthermore, the coupling stub is configured as a straight line for coupling with the diameter portion of a semicircle or semiellipse.

[0018] Furthermore, the total size of the driving patch, the parasitic patch, and the coupling stub is... And the cross-sectional height of the antenna is ,in This is the free-space wavelength corresponding to the center frequency of the antenna.

[0019] Furthermore, the dielectric substrate includes a metal ground plane and a substrate;

[0020] The driving patch, the parasitic patch, and the coupling stub are all disposed on the side of the substrate facing away from the metal floor.

[0021] In a second aspect, an electronic device is provided, comprising at least one low-profile single-layer broadband microstrip patch antenna as described in any one of the first aspects.

[0022] Thirdly, a radar detection system is provided, including:

[0023] At least one low-profile single-layer broadband microstrip patch antenna as described in any one of the first aspects;

[0024] The radar processing unit is connected to the antenna and performs target detection based on the signals received by the antenna.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. This invention provides a low-profile single-layer broadband microstrip patch antenna. Two symmetrical coupling stubs are led out near the open end of the driving patch to capacitively couple the left and right parasitic patches respectively. The symmetrical placement of the parasitic patches compensates for the inductive impedance of the driving patch, thereby aligning the resonant frequencies of the driving and parasitic patches and achieving broadband dual-mode formation. This effectively solves the problems of large patch unit size and high H-plane cross-polarization in traditional designs under low-profile, single-line polarization, and single-layer fabrication conditions.

[0027] 2. The antenna impedance bandwidth of the present invention achieves dual-mode coverage, with a -10dB bandwidth of 10.67%, which is about twice the bandwidth of the traditional patch with a -10dB bandwidth of 5.17%. If the width of the patch in the Y direction or the thickness in the Z direction is further increased, the bandwidth of the present invention can be further extended.

[0028] 3. The cross-polarization of this invention is 10dB lower than that of traditional patch, exhibiting a very low cross-polarization level. Furthermore, through multi-frequency simulation, the final radiation patterns at each frequency point are stable.

[0029] 4. The normal gain of this invention is greater than 7.6 dBi, which is 2.24 dB higher than that of traditional patch panels, and has a higher gain. Attached Figure Description

[0030] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0031] Figure 1 This is the H-plane radiation pattern of an E-type patch antenna in the prior art;

[0032] Figure 2 This is the H-plane radiation pattern of a U-slot patch antenna in the prior art;

[0033] Figure 3 This is a schematic diagram of the overall structure of the microstrip patch antenna in an embodiment of the present invention;

[0034] Figure 4 This is a side view of the microstrip patch antenna in an embodiment of the present invention;

[0035] Figure 5 This is a top view of the microstrip patch antenna in an embodiment of the present invention;

[0036] Figure 6 This is a Smith chart of the driving patch without coupling branches in this embodiment of the invention;

[0037] Figure 7 This is a schematic diagram of the microstrip patch antenna without coupling stubs in an embodiment of the present invention;

[0038] Figure 8 This is a schematic diagram comparing the simulation results of S11 in an embodiment of the present invention;

[0039] Figure 9 These are simulation results of the H-plane orientation pattern in an embodiment of the present invention;

[0040] Figure 10 The simulation results are for the H-plane radiation pattern of a traditional patch antenna in the existing technology;

[0041] Figure 11 This is the simulation result of the E-plane orientation pattern in the embodiment of the present invention;

[0042] Figure 12 This is a comparison chart of gain curves in an embodiment of the present invention.

[0043] The attached diagram shows the markings and corresponding component names:

[0044] 101. Dielectric substrate; 102. Metal ground plane; 103. Substrate; 104. Driver patch; 105. Parasitic patch; 106. Coupling stub; 107. Coaxial probe. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0046] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly or indirectly attached to that other component. When a component is referred to as being "connected to" another component, it can be directly or indirectly connected to that other component.

[0047] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0048] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0049] Example 1: A low-profile single-layer broadband microstrip patch antenna, such as Figure 3-5 As shown, it includes a dielectric substrate 101, a driving patch 104, two parasitic patches 105, and two symmetrical coupling stubs 106.

[0050] Specifically, the dielectric substrate 101 includes a metal ground plane 102 and a substrate 103; the driving patch 104, parasitic patch 105, and coupling stub 106 are all disposed on the side of the substrate 103 facing away from the metal ground plane 102. The driving patch 104 is disposed on the dielectric substrate 101 and is fed through a coaxial probe 107. The inner conductor of the coaxial probe 107 passes through the PCB and is soldered to the driving patch 104, while the outer conductor is grounded. Two parasitic patches 105 are symmetrically disposed on both sides of the driving patch 104; two symmetrical coupling stubs 106 are led out from the open end of the driving patch 104 and capacitively coupled to the two parasitic patches 105 respectively; wherein, the operating wavelength of the driving patch 104 and the parasitic patch 105 is configured to be half the waveguide wavelength, and dual-mode excitation is achieved through the capacitive coupling of the coupling stubs 106 to form a broadband antenna structure.

[0051] In this embodiment, the driving patch 104, parasitic patch 105, and coupling stub 106 are all rectangular in shape.

[0052] In this embodiment, the total size of the driving patch 104, the parasitic patch 105, and the coupling stub 106 is [size missing]. And the cross-sectional height of the antenna is For example, 0.043 ;in This is the free-space wavelength corresponding to the center frequency of the antenna.

[0053] To address the issues of large patch unit size and high H-plane cross-polarization in traditional designs under low profile, single-line polarization, and single-layer processing conditions, this invention introduces two symmetrical coupling stubs 106 near the open end of the driving patch 104 to capacitively couple parasitic patches 105 to the left and right, respectively, with the parasitic patches 105 placed symmetrically.

[0054] The function of coupling stub 106 is as follows: When there is no coupling stub 106, and only the driving patch 104 and the parasitic patch 105 are present, it is difficult to tune the resonant points of the driving patch 104 and the parasitic patch 105 together on S11. This is because the impedance curve Z11 of the driving patch 104 exhibits inductive behavior on the Smith chart, as shown below. Figure 6 As shown. If only the driver patch 104 and the parasitic patch 105 are arranged as follows... Figure 7 The parasitic patch 105 is placed at the indicated position, and is excited by the current coupling from the edge of the driving patch 104. At this point, the driving patch 104 and the parasitic patch 105 are inductively coupled, and the mutual impedance Z12 between them (assuming the parasitic patch 105 also has a feed port) is also inductive. The total impedance of the feed port of the driving patch 104 is Z = Z11 + Z12, where Z11 and Z12 are both inductive. Therefore, when the resonant frequency of the parasitic patch 105 approaches the resonant frequency of the driving patch 104, it will worsen port S11 (increasing the inductive reactance), leading to difficulties in debugging.

[0055] Based on the above analysis, this invention proposes using the coupled stub 106 to capacitively couple and excite the parasitic patch 105, such as... Figure 5 As shown. At this time, the mutual impedance Z12 is capacitive, which can compensate for the inductive impedance Z11 of the driving patch 104 (Z=Z11+Z12), thereby enabling the resonant frequencies of the driving patch 104 and the parasitic patch 105 to be tuned together, realizing the dual-mode wideband formation of the driving patch 104 and the parasitic patch 105.

[0056] The antenna impedance bandwidth of this invention achieves dual-mode coverage, with a -10dB bandwidth of 10.67%, such as... Figure 8 As shown, the -10dB bandwidth of the solid red line is 16.05-17.86GHz; furthermore, Figure 8 The blue dashed line in the image shows a traditional patch antenna (same substrate 103, same thickness, size). As can be seen from S11, compared to the 5.17% -10dB bandwidth of the traditional patch, the present invention improves the bandwidth by approximately 1 times. If the width of the patch in the Y direction or the thickness in the Z direction is further increased, the bandwidth of the present invention can be further extended.

[0057] Furthermore, the present invention has a very low level of cross-polarization, and the radiation pattern and cross-polarization of the H-plane of the present invention are as follows: Figure 9As shown, the cross-polarization is better than -15dB within ±60°; the simulation results of the radiation pattern and cross-polarization of the H-plane of the traditional patch antenna are as follows. Figure 10 As shown, the cross-polarization of this invention is better than -5.4dB at ±60°, and is 10dB lower than that of traditional patches. The simulation results of the radiation pattern on the E-plane of this invention are as follows. Figure 11 As shown, the cross-polarization level is better than -38dB. Furthermore, through multi-frequency simulation, the radiation patterns at each frequency point are ultimately stable.

[0058] This invention has higher gain. The gain curves of this invention and traditional patches within the operating frequency band are as follows: Figure 12 As shown, within the operating frequency band, the normal gain of this invention is greater than 7.6 dBi, which is 2.24 dB higher than that of the traditional patch (compared to the lowest gain within the operating frequency band).

[0059] This invention is a dual-mode excitation method, compared with traditional dual-mode excitation schemes such as E-type patch antennas and U-slot patch antennas. Figure 9 , Figure 1 and Figure 2 The present invention has low cross-polarization, and the present invention Compared to typical sizes It is small in size.

[0060] Example 2: A low-profile single-layer broadband microstrip patch antenna, comprising a dielectric substrate 101, a driving patch 104, two parasitic patches 105, and two symmetrical coupling stubs 106.

[0061] Specifically, the dielectric substrate 101 includes a metal ground plane 102 and a substrate 103; the driving patch 104, parasitic patch 105, and coupling stub 106 are all disposed on the side of the substrate 103 facing away from the metal ground plane 102. The driving patch 104 is disposed on the dielectric substrate 101 and is fed through a coaxial probe 107. The inner conductor of the coaxial probe 107 passes through the PCB and is soldered to the driving patch 104, while the outer conductor is grounded. Two parasitic patches 105 are symmetrically disposed on both sides of the driving patch 104; two symmetrical coupling stubs 106 are led out from the open end of the driving patch 104 and capacitively coupled to the two parasitic patches 105 respectively; wherein, the operating wavelength of the driving patch 104 and the parasitic patch 105 is configured to be half the waveguide wavelength, and dual-mode excitation is achieved through the capacitive coupling of the coupling stubs 106 to form a broadband antenna structure.

[0062] In this embodiment, the driving patch 104 and the parasitic patch 105 are both circular or elliptical in shape, and the coupling branch 106 is adapted to be arc-shaped to maintain the capacitive coupling strength between the driving patch 104 and the parasitic patch 105.

[0063] In this embodiment, the total size of the driving patch 104, the parasitic patch 105, and the coupling stub 106 is [size missing]. And the cross-sectional height of the antenna is For example, 0.043 ;in This is the free-space wavelength corresponding to the center frequency of the antenna.

[0064] Example 3: A low-profile single-layer broadband microstrip patch antenna, comprising a dielectric substrate 101, a driving patch 104, two parasitic patches 105, and two symmetrical coupling stubs 106.

[0065] Specifically, the dielectric substrate 101 includes a metal ground plane 102 and a substrate 103; the driving patch 104, parasitic patch 105, and coupling stub 106 are all disposed on the side of the substrate 103 facing away from the metal ground plane 102. The driving patch 104 is disposed on the dielectric substrate 101 and is fed through a coaxial probe 107. The inner conductor of the coaxial probe 107 passes through the PCB and is soldered to the driving patch 104, while the outer conductor is grounded. Two parasitic patches 105 are symmetrically disposed on both sides of the driving patch 104; two symmetrical coupling stubs 106 are led out from the open end of the driving patch 104 and capacitively coupled to the two parasitic patches 105 respectively; wherein, the operating wavelength of the driving patch 104 and the parasitic patch 105 is configured to be half the waveguide wavelength, and dual-mode excitation is achieved through the capacitive coupling of the coupling stubs 106 to form a broadband antenna structure.

[0066] In this embodiment, both the driving patch 104 and the parasitic patch 105 are configured as semi-circular or semi-elliptical shapes. The coupling stub 106 is configured as an arc shape for coupling with the arc portion of the semi-circle or semi-ellipse.

[0067] In this embodiment, the total size of the driving patch 104, the parasitic patch 105, and the coupling stub 106 is [size missing]. And the cross-sectional height of the antenna is For example, 0.043 ;in This is the free-space wavelength corresponding to the center frequency of the antenna.

[0068] Example 4: A low-profile single-layer broadband microstrip patch antenna, comprising a dielectric substrate 101, a driving patch 104, two parasitic patches 105, and two symmetrical coupling stubs 106.

[0069] Specifically, the dielectric substrate 101 includes a metal ground plane 102 and a substrate 103; the driving patch 104, parasitic patch 105, and coupling stub 106 are all disposed on the side of the substrate 103 facing away from the metal ground plane 102. The driving patch 104 is disposed on the dielectric substrate 101 and is fed through a coaxial probe 107. The inner conductor of the coaxial probe 107 passes through the PCB and is soldered to the driving patch 104, while the outer conductor is grounded. Two parasitic patches 105 are symmetrically disposed on both sides of the driving patch 104; two symmetrical coupling stubs 106 are led out from the open end of the driving patch 104 and capacitively coupled to the two parasitic patches 105 respectively; wherein, the operating wavelength of the driving patch 104 and the parasitic patch 105 is configured to be half the waveguide wavelength, and dual-mode excitation is achieved through the capacitive coupling of the coupling stubs 106 to form a broadband antenna structure.

[0070] In this embodiment, both the driving patch 104 and the parasitic patch 105 are configured as semi-circular or semi-elliptical shapes. The coupling stub 106 is configured as a straight line for coupling with the diameter portion of the semi-circle or semi-ellipse.

[0071] In this embodiment, the total size of the driving patch 104, the parasitic patch 105, and the coupling stub 106 is [size missing]. And the cross-sectional height of the antenna is For example, 0.043 ;in This is the free-space wavelength corresponding to the center frequency of the antenna.

[0072] The present invention also describes an electronic device comprising at least one low-profile single-layer broadband microstrip patch antenna as described in any one of Embodiments 1-4.

[0073] The present invention also describes a radar detection system, including a radar processing unit and at least one low-profile single-layer broadband microstrip patch antenna as described in any one of Embodiments 1-4; the radar processing unit is connected to the antenna and performs target detection based on the signal received by the antenna.

[0074] Working Principle: This invention provides a low-profile, single-layer broadband microstrip patch antenna. Two symmetrical coupling stubs 106 are led out near the open end of the driving patch 104, capacitively coupling the left and right parasitic patches 105 respectively. The symmetrical placement of the parasitic patches 105 compensates for the inductive impedance of the driving patch 104, thereby aligning the resonant frequencies of the driving patch 104 and the parasitic patch 105, achieving broadband dual-mode formation. This effectively solves the problems of large patch unit size and high H-plane cross-polarization in traditional designs under low-profile, single-line polarization, and single-layer fabrication conditions.

[0075] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A low-profile single-layer broadband microstrip patch antenna, characterized in that, include: Dielectric substrate (101); A drive patch (104) is disposed on the dielectric substrate (101) and fed through a coaxial probe (107); Two parasitic patches (105) are symmetrically arranged on both sides of the driving patch (104); And two symmetrical coupling stubs (106) are led out from the open end of the driving patch (104) and capacitively coupled to the two parasitic patches (105), respectively. The driving patch (104) and the parasitic patch (105) are configured to operate at half the waveguide wavelength, and dual-mode excitation is achieved through capacitive coupling of the coupling stub (106) to form a broadband antenna structure.

2. The low-profile single-layer broadband microstrip patch antenna according to claim 1, characterized in that, The driving patch (104) and the parasitic patch (105) are configured to be rectangular, circular or elliptical.

3. The low-profile single-layer broadband microstrip patch antenna according to claim 2, characterized in that, When the driving patch (104) and the parasitic patch (105) are circular or elliptical, the coupling branch (106) is adapted to be arc-shaped to maintain the capacitive coupling strength between the driving patch (104) and the parasitic patch (105).

4. The low-profile single-layer broadband microstrip patch antenna according to claim 1, characterized in that, The driving patch (104) and the parasitic patch (105) are configured in a semi-circular or semi-elliptical shape.

5. A low-profile single-layer broadband microstrip patch antenna according to claim 4, characterized in that, The coupling stub (106) is configured in an arc shape for coupling with the arc portion of a semicircle or semiellipse.

6. A low-profile single-layer broadband microstrip patch antenna according to claim 4, characterized in that, The coupling stub (106) is configured as a straight line for coupling with the diameter portion of a semicircle or semiellipse.

7. A low-profile single-layer broadband microstrip patch antenna according to claim 1, characterized in that, The total dimensions of the driving patch (104), the parasitic patch (105), and the coupling stub (106) are: And the cross-sectional height of the antenna is ,in This is the free-space wavelength corresponding to the center frequency of the antenna.

8. A low-profile single-layer broadband microstrip patch antenna according to claim 1, characterized in that, The dielectric substrate (101) includes a metal ground plane (102) and a substrate (103); The driving patch (104), the parasitic patch (105), and the coupling stub (106) are all disposed on the side of the substrate (103) facing away from the metal floor (102).

9. An electronic device, characterized in that, It includes at least one low-profile single-layer broadband microstrip patch antenna as described in any one of claims 1-8.

10. A radar detection system, characterized in that, include: At least one low-profile single-layer broadband microstrip patch antenna as described in any one of claims 1-8; The radar processing unit is connected to the antenna and performs target detection based on the signals received by the antenna.

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