Low profile two-dimensional wide-angle scanning end-fire antenna array

Abstract

The application belongs to the technical field of antenna engineering, and particularly relates to a low-profile two-dimensional wide-angle scanning end-fire antenna array. The end-fire antenna array comprises: a first end-fire antenna array and a second end-fire antenna array arranged in parallel, and antenna units with opposite directions, equal amplitudes and opposite phases are arranged on the first end-fire antenna array and the second end-fire antenna array in an array mode; the antenna unit comprises a feeding metal column, a metal patch, a short-circuit metal column, an arc-shaped slot, a dielectric substrate, a metal frame and a metal ground plate. The low-profile two-dimensional wide-angle scanning end-fire antenna array is compact in design, low in profile and omnidirectional in radiation, can realize omnidirectional scanning in the azimuth plane and large-angle scanning in the elevation plane, and provides technical support for improving the low wind resistance and large-angle comprehensive performance of a radar antenna.

Description

Technical Field

[0001] This application belongs to the field of antenna engineering technology, and specifically relates to a low-profile two-dimensional wide-angle scanning end-fire antenna array. Background Technology

[0002] With the continuous development of antenna engineering technology, advanced multi-functional radar systems have put forward higher requirements for phased array antennas: first, wide beam coverage angle and small scanning blind zone; second, low wind resistance, so as not to affect the maneuverability and stealth of the carrier aircraft.

[0003] Traditional phased array radars often use edge-fired array antennas as the radiating end. To ensure long-range detection accuracy, the array surface needs a sufficiently large aperture area in the target direction to achieve the required high gain performance. However, during large-angle scanning, the excessively large aperture area will severely affect the aerodynamic characteristics and maneuverability of the carrier platform. In contrast, end-fired array antennas radiate parallel to the array surface, and their directivity coefficient is not limited by the aperture size in the maximum radiation direction. This can be used to reconcile the contradiction between radiation performance and the aerodynamic performance of the carrier aircraft, which is of great significance for improving the operational efficiency and survivability of the carrier platform. Currently, end-fired antenna array research and applications mostly use directional end-fired array elements such as Yagi antennas and circumferential antennas, arranged in a one-dimensional edge-fired array to form an end-fired beam that can be electrically scanned in the azimuth plane. Due to the high directivity of the array element radiation pattern, this type of antenna array often suffers from problems such as a small azimuth plane scanning range and a large array surface size. To address this, existing research has proposed using antennas with omnidirectional azimuth plane radiation, such as monopoles, as array elements, which can expand the azimuth plane scanning range and improve the beam coverage angle domain. However, many antennas suffer from large profile heights, making conformal integration with platforms difficult. This is especially true for low-frequency antennas, where excessively large profile dimensions severely impact the aerodynamics and maneuverability of the mounting platform, hindering their engineering applications. Furthermore, existing end-fire antenna array research primarily focuses on azimuth beam scanning design, with limited attention paid to improving elevation scanning performance. Further research and exploration are urgently needed to expand the two-dimensional beam coverage and enhance the antenna's effective angular domain.

[0004] Therefore, there is an urgent need for a technical solution to overcome or mitigate at least one of the aforementioned defects in the existing technology. Summary of the Invention

[0005] The purpose of this application is to provide a low-profile two-dimensional wide-angle scanning end-fire antenna array to solve the problems of high profile size and limited scanning range that often exist in traditional end-fire antenna arrays.

[0006] The technical solution of this application is:

[0007] A low-profile two-dimensional wide-angle scanning end-fire antenna array includes:

[0008] A first end-fire antenna array and a second end-fire antenna array are arranged in parallel. The first end-fire antenna array and the second end-fire antenna array have antenna elements with opposite orientations and equal amplitude and anti-phase feeding arranged in an array manner.

[0009] The antenna unit includes a feed metal post, a metal patch, a short-circuit metal post, an arc-shaped slot, a dielectric substrate, a metal frame, and a metal ground plane.

[0010] The metal frame is mounted on the metal floor;

[0011] The dielectric substrate is rectangular and is disposed on the metal frame;

[0012] The metal patch is circular and disposed on the dielectric substrate, and the metal patch has a plurality of axially symmetrically distributed arc-shaped slits.

[0013] The feed metal post is located at the center of the antenna element. One end of the feed metal post passes through the dielectric substrate and is connected to the metal patch, while the other end passes through the metal ground plane.

[0014] The short-circuit metal pillars include three, located outside the arc-shaped gap. The three short-circuit metal pillars are evenly arranged along the circumference of the metal patch, with one end passing through the dielectric substrate and connected to the metal patch, and the other end connected to the metal ground.

[0015] In at least one embodiment of this application, the arc-shaped gaps are arranged in two rings on the metal patch, with three gaps evenly arranged in each ring along the circumference of the metal patch, and the arc-shaped gaps in the inner and outer rings are staggered.

[0016] In at least one embodiment of this application, one metal frame is disposed at each of the four corners of the dielectric substrate.

[0017] In at least one embodiment of this application, the metal frame is in the shape of an L-shaped corner piece.

[0018] In at least one embodiment of this application, each antenna element on the first end-fire antenna array and the second end-fire antenna array is arranged in a rectangular pattern of 0.3λ*0.3λ, where λ is the wavelength of the operating frequency in free space.

[0019] In at least one embodiment of this application, the cross-sectional dimension of each antenna element on the first end-fire antenna array and the second end-fire antenna array is 0.04λ.

[0020] In at least one embodiment of this application, when beamforming along the end-fire direction, the antenna elements at the end of the first end-fire antenna array and the second end-fire antenna array along the end-fire direction are all set as virtual elements, and the remaining antenna elements are set as real elements. The excitation amplitude is uniformly distributed, and the excitation phase difference between adjacent antenna elements is 0.6π. The first end-fire antenna array and the second end-fire antenna array are fed with equal amplitude and opposite phase.

[0021] In at least one embodiment of this application, when scanning along the azimuth plane beam, the antenna elements of the last row and column of the first end-fire antenna array and the second end-fire antenna array along the scanning direction are set as virtual elements, and the remaining antenna elements are set as real elements. The excitation amplitude is uniformly distributed. The excitation phase of the antenna elements of the first end-fire antenna array is 0.6π×(icosφ+jsinφ), where i and j are the row and column numbers of the antenna elements, and φ is the azimuth plane beam pointing angle. The first end-fire antenna array and the second end-fire antenna array are fed with equal amplitude and opposite phase.

[0022] In at least one embodiment of this application, during upper half-space beam scanning, all antenna elements of the second end-fire antenna array are set as virtual elements, the antenna elements of the last row and column of the first end-fire antenna array along the scanning direction are set as virtual elements, and the remaining antenna elements are set as real elements. The excitation amplitude is uniformly distributed, and the excitation phase of the antenna elements of the first end-fire antenna array is 0.6π×(isinθcosφ+jsinθsinφ), where θ is the beam pointing angle of the elevation plane.

[0023] In at least one embodiment of this application, during lower half-space beam scanning, all antenna elements of the first end-fire antenna array are set as virtual elements, the antenna elements of the last row and column of the second end-fire antenna array along the scanning direction are set as virtual elements, and the remaining antenna elements are set as real elements. The excitation amplitude is uniformly distributed, and the excitation phase of the antenna elements of the second end-fire antenna array is 0.6π×(isinθcosφ+jsinθsinφ).

[0024] The invention has at least the following beneficial technical effects:

[0025] The low-profile two-dimensional wide-angle scanning end-fire antenna array of this application features a compact low-profile omnidirectional radiating array element, which can achieve omnidirectional scanning in the azimuth plane and large-angle scanning in the elevation plane, providing technical support for improving the low wind resistance and large-angle comprehensive performance of radar antennas. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of a low-profile two-dimensional wide-angle scanning end-fire antenna array antenna element according to one embodiment of this application;

[0027] Figure 2 This is a schematic diagram of an end-fire antenna array structure according to one embodiment of this application;

[0028] Figure 3 This is a side view of an end-fire antenna array structure according to one embodiment of this application;

[0029] Figure 4 This is an azimuth beam scanning pattern of an end-fire antenna array according to one embodiment of this application;

[0030] Figure 5 This is an elevation beam scanning pattern of an end-fire antenna array according to one embodiment of this application.

[0031] in:

[0032] 1-Power supply metal pillar, 2-Metal patch, 3-Short circuit metal pillar, 4-Arc-shaped gap, 5-Dielectric substrate, 6-Metal frame, 7-Metal floor. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0034] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "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 this application 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 limiting the scope of protection of this application.

[0035] The following is in conjunction with the appendix Figures 1 to 5 This application will be described in further detail.

[0036] This application provides a low-profile two-dimensional wide-angle scanning end-fire antenna array, including: a first end-fire antenna array 8 and a second end-fire antenna array 9 arranged in parallel, wherein antenna elements with opposite orientations and equal amplitude and anti-phase feeding are arranged on the first end-fire antenna array 8 and the second end-fire antenna array 9 in an array manner.

[0037] Specifically, such as Figure 1 , 2 As shown, the antenna unit includes a feeding metal pillar 1, a metal patch 2, a short-circuit metal pillar 3, an arc-shaped slot 4, a dielectric substrate 5, a metal frame 6, and a metal ground plane 7. The metal frame 6 is disposed on the metal ground plane 7. The dielectric substrate 5 is rectangular and disposed on the metal frame 6. The metal patch 2 is circular and disposed on the dielectric substrate 5. Multiple axially symmetrically distributed arc-shaped slots 4 are formed on the metal patch 2. The feeding metal pillar 1 is located at the center of the antenna unit. One end of the feeding metal pillar 1 passes through the dielectric substrate 5 and is connected to the metal patch 2, and the other end passes through the metal ground plane 7. There are three short-circuit metal pillars 3, located outside the arc-shaped slots 4. The three short-circuit metal pillars 3 are evenly arranged along the circumference of the metal patch 2. One end passes through the dielectric substrate 5 and is connected to the metal patch 2, and the other end is connected to the metal ground plane 7.

[0038] The low-profile two-dimensional wide-angle scanning end-fire antenna array of this application has a feeding metal pillar 1 and a short-circuit metal pillar 3 that pass through a dielectric substrate 5 and are connected to a circular metal patch 2, thereby extending the current path laterally and achieving the effects of reducing the profile height and impedance matching. The axisymmetrically distributed arc-shaped gaps 4 are etched on the circular metal patch 2, and the lateral dimension of the top-loaded patch is reduced by meandering technology, thereby achieving a compact array element effect.

[0039] In a preferred embodiment of this application, two concentric arc-shaped slots 4 are arranged on the metal patch 2, one inside and one outside, with three slots evenly distributed in each concentric circle along the circumference of the metal patch 2. The arc-shaped slots 4 in the inner and outer concentric circles are staggered. Both the arc-shaped slots 4 and the short-circuit metal pillars 3 are arranged axially symmetrically at 120° angular intervals. This reduces the size of the antenna element while improving the consistency of the azimuth radiation performance of the element, thereby improving the consistency of the azimuth omnidirectional scanning beam performance of the first end-fire antenna array 8 and the second end-fire antenna array 9.

[0040] In a preferred embodiment of this application, a metal frame 6 is disposed at each of the four corners of the dielectric substrate 5. In this embodiment, the metal frame 6 is L-shaped. The metal frame 6 is connected to the metal ground plate 7 to provide support for the dielectric substrate 5.

[0041] The low-profile two-dimensional wide-angle scanning end-fire antenna array of this application has antenna elements arranged in a 0.3λ*0.3λ rectangular pattern on the first end-fire antenna array 8 and the second end-fire antenna array 9, where λ is the wavelength of the operating frequency in free space. The cross-sectional dimension of each antenna element on the first end-fire antenna array 8 and the second end-fire antenna array 9 is 0.04λ.

[0042] The low-profile two-dimensional wide-angle scanning end-fire antenna array of this application, the first end-fire antenna array 8 and the second end-fire antenna array 9 follow a specific excitation scheme when realizing two-dimensional wide-angle beam scanning, specifically:

[0043] When beamforming along the end-fire direction, the antenna elements at the end of the first end-fire antenna array 8 and the second end-fire antenna array 9 along the end-fire direction are all set as virtual elements, and the remaining antenna elements are set as real elements. The excitation amplitude is uniformly distributed, and the excitation phase difference between adjacent antenna elements is 0.6π. The first end-fire antenna array 8 and the second end-fire antenna array 9 are fed with equal amplitude and opposite phase. This design of virtual and real elements of antenna elements can avoid strong port reflection caused by strong coupling under end-fire conditions.

[0044] When scanning along the azimuth plane beam, the antenna elements in the last row and column of the first end-fire antenna array 8 and the second end-fire antenna array 9 along the scanning direction are set as virtual elements, and the remaining antenna elements are set as real elements. The excitation amplitude is uniformly distributed. The excitation phase of the antenna elements of the first end-fire antenna array 8 is 0.6π×(icosφ+jsinφ), where i and j are the row and column numbers of the antenna elements, and φ is the azimuth plane beam pointing angle. The first end-fire antenna array 8 and the second end-fire antenna array 9 are fed with equal amplitude and opposite phase.

[0045] During upper half-space beam scanning, all antenna elements of the second end-fire antenna array 9 are set as virtual elements, the antenna elements of the last row and column of the first end-fire antenna array 8 along the scanning direction are set as virtual elements, and the remaining antenna elements are set as real elements. The excitation amplitude is uniformly distributed, and the excitation phase of the antenna elements of the first end-fire antenna array 8 is 0.6π×(isinθcosφ+jsinθsinφ), where θ is the beam pointing angle of the elevation plane.

[0046] During lower half-space beam scanning, all antenna elements of the first end-fire antenna array 8 are set as virtual elements, and the antenna elements of the last row and column of the second end-fire antenna array 9 along the scanning direction are set as virtual elements, while the remaining antenna elements are set as real elements. The excitation amplitude is uniformly distributed, and the excitation phase of the antenna elements of the second end-fire antenna array 9 is 0.6π×(isinθcosφ+jsinθsinφ).

[0047] Based on the above dual-array port excitation scheme, the low-profile two-dimensional wide-angle scanning end-fire antenna array can achieve two-dimensional beam scanning in the azimuth plane omnidirectional and the elevation plane wide-angle range.

[0048] The low-profile two-dimensional wide-angle scanning end-fire antenna array of this application, based on the above antenna element design, constructs an M*N-sized end-fire antenna array with a 0.3λ*0.3λ rectangular arrangement. Through amplitude and phase modulation optimization, omnidirectional scanning in the azimuth plane can be achieved. For example... Figure 3As shown, the first end-fire antenna array 8 and the second end-fire antenna array 9, with opposite orientations and equal amplitude anti-phase feeds, further enhance the end-fire gain through beamforming, achieving omnidirectional beam scanning in the azimuth plane. Furthermore, based on the single-array beam uptilt effect, the upper and lower arrays are excited separately, and combined with excitation signal modulation optimization, wide-angle scanning in the elevation plane is achieved, broadening the two-dimensional scanning angular domain.

[0049] In one specific embodiment of this application, the azimuth beam scanning pattern of the end-fire antenna array is as follows: Figure 4 As shown in the figure, due to structural symmetry, only the beam scanning results in the 0º~180º range are displayed; the results in the 180º~360º range are the same. The results show that the proposed design can achieve omnidirectional beam scanning in the azimuth plane from 0º to 360º, with a gain range of 13.7dB~14.6dB, scanning loss within 1.3dB, and good beam consistency in the scanning angular domain.

[0050] In one specific embodiment of this application, the elevation beam scanning pattern of the end-fire antenna array is as follows: Figure 5 As shown in the figure, equal-amplitude, anti-phase dual-array beamforming is used to enhance end-fire gain in the end-fire direction, achieving omnidirectional coverage in the azimuth plane. Then, the upper and lower arrays are excited separately, and combined with amplitude and phase modulation optimization, large-angle beam coverage in the vertical space can be achieved. As can be seen from the results in the figure, the elevation beam scanning range is ±55º, and a gain range of 12.5dB to 15.6dB can be achieved.

[0051] This application presents a low-profile two-dimensional wide-angle scanning end-fire antenna array, which is an improved design for monopole antennas. By introducing a top-loaded metal patch with etched symmetrical arc-shaped slots and a short-circuit structure, a compact low-profile omnidirectional radiating element is achieved, reducing the monopole profile height to approximately 0.04λ, which is about 80% lower than the profile height of traditional monopole antenna elements. Simultaneously, the lateral dimension of the antenna element does not exceed 0.3λ, maintaining array compactness and facilitating wide-angle scanning performance. Based on the improved element, a dual-array end-fire antenna array with equal amplitude and phase inversion is constructed. Through amplitude and phase modulation optimization, omnidirectional scanning performance in the azimuth plane (0º~360º angle range) and beam scanning performance in the elevation plane (±55º angle range) are achieved.

[0052] The low-profile two-dimensional wide-angle scanning end-fire antenna array of this application has the following advantages:

[0053] By employing a top-loaded metal patch with an etched arc-shaped slot and a short-circuit structure, a compact low-profile omnidirectional radiating monopole array element with a cross-sectional dimension of 0.04λ and a lateral dimension not exceeding 0.3λ was achieved. This not only realizes a low-profile antenna array but also avoids the problem of limited scanning angular domain caused by excessively large element spacing.

[0054] By employing two sets of dual-array end-fire antennas with opposite orientations and equal-amplitude anti-phase feeds, the end-fire gain is improved, while design flexibility is increased, the two-dimensional beam scanning range is expanded, and the antenna's effective angular domain is enhanced.

[0055] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A low-profile two-dimensional wide-angle scanning end-fire antenna array, characterized in that, include: The first end-fire antenna array (8) and the second end-fire antenna array (9) are arranged in parallel. The first end-fire antenna array (8) and the second end-fire antenna array (9) have antenna elements with opposite orientations and equal amplitude and anti-phase feeding arranged in an array manner. The antenna unit includes a feed metal post (1), a metal patch (2), a short-circuit metal post (3), an arc-shaped slot (4), a dielectric substrate (5), a metal frame (6), and a metal ground plane (7), wherein... The metal frame (6) is mounted on the metal floor (7); The dielectric substrate (5) is rectangular and is disposed on the metal frame (6); The metal patch (2) is circular and is disposed on the dielectric substrate (5). Multiple axially symmetrically distributed arc-shaped slits (4) are provided on the metal patch (2). The feeding metal post (1) is located at the center of the antenna unit. One end of the feeding metal post (1) passes through the dielectric substrate (5) and is connected to the metal patch (2), and the other end passes through the metal ground plane (7). The short-circuit metal pillars (3) include three, located outside the arc-shaped gap (4). The three short-circuit metal pillars (3) are evenly arranged along the circumference of the metal patch (2), with one end passing through the dielectric substrate (5) and connected to the metal patch (2), and the other end connected to the metal floor (7).

2. The low-profile two-dimensional wide-angle scanning end-fire antenna array according to claim 1, characterized in that, The arc-shaped gaps (4) are arranged in two rings on the metal patch (2), with three gaps evenly arranged in each ring along the circumference of the metal patch (2), and the arc-shaped gaps (4) in the inner and outer rings are staggered.

3. The low-profile two-dimensional wide-angle scanning end-fire antenna array according to claim 2, characterized in that, One metal frame (6) is disposed at each of the four corners of the dielectric substrate (5).

4. The low-profile two-dimensional wide-angle scanning end-fire antenna array according to claim 3, characterized in that, The metal frame (6) is L-shaped with corner pieces.

5. The low-profile two-dimensional wide-angle scanning end-fire antenna array according to claim 4, characterized in that, Each antenna element on the first end-fire antenna array (8) and the second end-fire antenna array (9) is arranged in a rectangular pattern of 0.3λ*0.3λ, where λ is the wavelength of the operating frequency in free space.

6. The low-profile two-dimensional wide-angle scanning end-fire antenna array according to claim 5, characterized in that, The cross-sectional dimension of each antenna element on the first end-fire antenna array (8) and the second end-fire antenna array (9) is 0.04λ.

7. The low-profile two-dimensional wide-angle scanning end-fire antenna array according to claim 6, characterized in that, When beamforming along the end-fire direction, the antenna elements at the end of the first end-fire antenna array (8) and the second end-fire antenna array (9) along the end-fire direction are all set as virtual elements, and the remaining antenna elements are set as real elements. The excitation amplitude is uniformly distributed, and the excitation phase difference between adjacent antenna elements is 0.6π. The first end-fire antenna array (8) and the second end-fire antenna array (9) are fed with equal amplitude and opposite phase.

8. The low-profile two-dimensional wide-angle scanning end-fire antenna array according to claim 7, characterized in that, When scanning along the azimuth plane beam, the antenna elements of the last row and column of the first end-fire antenna array (8) and the second end-fire antenna array (9) along the scanning direction are set as virtual elements, and the remaining antenna elements are set as real elements. The excitation amplitude is uniformly distributed. The excitation phase of the antenna elements of the first end-fire antenna array (8) is 0.6π×(icosφ+jsinφ), where i and j are the row and column numbers of the antenna elements, and φ is the azimuth plane beam pointing angle. The first end-fire antenna array (8) and the second end-fire antenna array (9) are fed with equal amplitude and opposite phase.

9. The low-profile two-dimensional wide-angle scanning end-fire antenna array according to claim 8, characterized in that, During upper half-space beam scanning, all antenna elements of the second end-fire antenna array (9) are set as virtual elements, the antenna elements of the last row and column of the first end-fire antenna array (8) along the scanning direction are set as virtual elements, and the remaining antenna elements are set as real elements. The excitation amplitude is uniformly distributed. The excitation phase of the antenna elements of the first end-fire antenna array (8) is 0.6π×(isinθcosφ+jsinθsinφ), where θ is the beam pointing angle of the elevation plane.

10. The low-profile two-dimensional wide-angle scanning end-fire antenna array according to claim 9, characterized in that, During lower half-space beam scanning, all antenna elements of the first end-fire antenna array (8) are set as virtual elements, the antenna elements of the last row and column of the second end-fire antenna array (9) along the scanning direction are set as virtual elements, and the remaining antenna elements are set as real elements. The excitation amplitude is uniformly distributed, and the excitation phase of the antenna elements of the second end-fire antenna array (9) is 0.6π×(isinθcosφ+jsinθsinφ).

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