Antenna and aircraft

Abstract

The application discloses an antenna and an aircraft, and relates to the technical field of antennas, and specifically discloses an antenna comprising a top loading part, a metal floor, a monopole and a plurality of grounding columns, wherein the top loading part and the metal floor are spaced apart and parallel to each other, one end of each of the grounding columns is arranged at the edge of the top loading part, the other end of each of the grounding columns is connected to the metal floor, and the monopole is arranged below the top loading part, wherein the top loading part is circular and comprises a center part arranged in a central region, a first top loading circular ring connected to the center part, a second top loading circular ring concentrically arranged with the first top loading circular ring and separated from each other, and a square resistance sheet connected to the second top loading circular ring and separated from the first top loading circular ring and forming a circular ring-shaped gap. The antenna of the application performs square resistance distribution loading on the top loading part through the square resistance sheet, optimizes the radiation impedance, and improves the overall gain of the antenna.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and in particular to an antenna and an aircraft. Background Technology

[0002] Ultra-high frequency (UHF) wireless communication operates within the 300MHz-3000MHz frequency range. UHF communication offers advantages such as a wide usable frequency range, simple manufacturing, and small equipment size, leading to its widespread application in both military and civilian fields. UHF frequency-hopping communication is an important communication method, especially in modern military communications. It possesses strong data transmission and anti-interference capabilities, and also offers advantages such as high spectrum utilization, resistance to multipath propagation and fading, and ease of network deployment.

[0003] Wireless communication is inseparable from antennas, as they serve as the entry and exit points in radio frequency (RF) wireless communication systems, acting as the conversion medium between spatial electromagnetic signals and waveguide devices. The performance of an antenna directly impacts the overall quality of the communication system. In frequency-hopping communication within the ultra-high frequency (UHF) band, UHF broadband antennas are particularly important due to their wide operating frequency range. Practical applications require antennas to cover a broad operating frequency band while maintaining a small size, making the design of miniaturized broadband antennas very challenging. Therefore, research on high-performance, wide-bandwidth, and miniaturized UHF antennas is crucial.

[0004] Currently, commercially available UHF band antennas are generally whip-shaped or disc-shaped monopole antennas. Whip-shaped or disc-shaped monopole antennas require excessive height to resonate. To reduce this height, an RLC network containing lossy components is used for port matching. Port-matched lossy components dissipate more radiated energy than the same value distributed across the antenna, typically by more than 50%. Therefore, current UHF band antennas, due to the use of RLC matching networks, suffer from low overall gain, especially in the low-frequency band where the electrical length is even smaller, resulting in excessively low gain. Summary of the Invention

[0005] In view of the above problems, the purpose of this invention is to provide an antenna and an aircraft that can tune the radiation impedance of the antenna across the entire frequency band, ensure low-frequency gain, improve the overall gain of the antenna across the entire frequency band, and improve the communication quality of the aircraft.

[0006] According to one aspect of the present invention, an antenna is provided, the antenna comprising: a top loading portion, a metal ground plane, a monopole, and a plurality of grounding posts, wherein the top loading portion and the metal ground plane are spaced apart from each other and parallel to each other, one end of each grounding post is disposed at the edge of the top loading portion, and the other end of each grounding post is connected to the metal ground plane, the monopole is disposed below the top loading portion, wherein the top loading portion is circular and includes:

[0007] It is located at the center of the circular region;

[0008] The first top-loading ring is connected to the central part;

[0009] The second top loading ring is concentrically arranged with the first top loading ring but separate from it;

[0010] The square resist sheet is connected to the second top loading ring and is separated from the first top loading ring to form an annular gap.

[0011] Optionally, the monopole is in the form of a cone, the bottom surface of which is located below and connected to the center of the top loading portion, and the apex of which extends toward the metal floor.

[0012] Optionally, the projection of the vertex of the cone onto the plane where the top loading portion is located coincides with the center of the top loading portion.

[0013] Optionally, a feed hole is provided at the center of the metal floor, and the antenna further includes:

[0014] The power supply section includes a top end and a bottom end. The top end of the power supply section passes through the power supply hole of the metal floor to receive external power supply signals, and the bottom end of the power supply section is connected to the cone top of the monopole.

[0015] Optionally, the antenna further includes:

[0016] The first metal sleeve is frustoconical and fits around the power supply section, and is spaced apart from the plurality of grounding posts.

[0017] Optionally, the first metal sleeve includes a bottom end and a top end, the bottom end of the first metal sleeve is connected to the metal floor, the top end of the first metal sleeve is close to the top loading part, and the cross-sectional dimension of the first metal sleeve gradually decreases from bottom to top.

[0018] Optionally, the antenna further includes:

[0019] The second metal sleeve is frustoconical and is fitted around the monopole, located above the first metal sleeve and connected to the first metal sleeve.

[0020] Optionally, the second metal sleeve includes a bottom end and a top end, the bottom end of the second metal sleeve is connected to the top end of the first metal sleeve, the top end of the second metal sleeve is close to the top loading portion, and the cross-sectional dimension of the second metal sleeve gradually increases from bottom to top.

[0021] Optionally, the conical axis of the monopole, the central axis of the first metal sleeve, and the central axis of the second metal sleeve coincide and are perpendicular to the plane where the top loading part is located.

[0022] According to another aspect of the present invention, an aircraft is provided, the aircraft including the antenna provided by the present invention.

[0023] The antenna provided by the present invention includes: a top loading part, a metal ground plane, a monopole, and a plurality of grounding posts. The top loading part and the metal ground plane are spaced apart and parallel to each other. One end of each grounding post is disposed at the edge of the top loading part, and the other end of each grounding post is connected to the metal ground plane. The monopole is disposed below the top loading part. The top loading part is circular and includes: a central part disposed in the central region; a first top loading ring connected to the central part; a second top loading ring concentrically disposed with the first top loading ring and separated from it; and a sheet resistor connected to the second top loading ring and separated from the first top loading ring to form an annular gap. By utilizing a separate structure of a first top-loading ring and a second top-loading ring, and placing a sheet resistor between the two top-loading rings, connected only to the second top-loading ring, the first top-loading ring provides high-frequency radiation loading, while the second top-loading ring provides low-frequency radiation loading. The sheet resistor, positioned between the two, distributes and concentrates the top-loading portion, tuning its radiation impedance and increasing the electrical length of the second top-loading ring in the low-frequency band, while simultaneously ensuring the electrical length of the first top-loading ring in the high-frequency band. The antenna provided by this invention improves the electrical length and gain in the low-frequency band while ensuring the electrical length and gain in the high-frequency band, thereby improving the overall gain of the antenna across the entire frequency band.

[0024] The antenna provided by the present invention has a first metal sleeve with a cross-sectional size that gradually decreases from bottom to top, which is installed around a monopole. The bottom end of the first metal sleeve is connected to the ground, thereby expanding the antenna bandwidth, improving the overall matching effect of the antenna, and realizing the miniaturization of the antenna.

[0025] The antenna provided by the present invention has a second metal sleeve with a cross-sectional size that increases from the bottom to the top outside the monopole. The bottom end of the second metal sleeve is connected to the top end of the first metal sleeve, which further improves the overall matching effect of the antenna and reduces the antenna size.

[0026] The aircraft provided by this invention uses the antenna provided by this invention, which has high overall gain and good communication quality in the ultra-high frequency full-band wireless communication signal. Attached Figure Description

[0027] The above and other objects, features and advantages of the present invention will become more apparent from the following description of embodiments of the invention with reference to the accompanying drawings, in which:

[0028] Figure 1A top view of the top loading portion of an antenna according to an embodiment of the present invention is shown;

[0029] Figure 2 A three-dimensional structural schematic diagram of an antenna according to an embodiment of the present invention is shown;

[0030] Figure 3 A top view of a simulated installation environment for an antenna according to an embodiment of the present invention is shown;

[0031] Figure 4 The port voltage standing wave ratio of an antenna according to an embodiment of the present invention is shown;

[0032] Figure 5 The minimum gain of the antenna at various frequencies at different elevation angles is shown at the port of the antenna according to an embodiment of the present invention. Detailed Implementation

[0033] Various embodiments of the invention will now be described in more detail with reference to the accompanying drawings. In the various drawings, the same elements are indicated by the same or similar reference numerals. For clarity, the various parts in the drawings are not drawn to scale.

[0034] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0035] Figure 1 This diagram shows a top view of the top loading portion of an antenna according to an embodiment of the present invention. The top loading portion 110 of the antenna according to this embodiment includes a central portion 5, a first top loading ring 1, a second top loading ring 2, and a square resistive plate 3. The top loading portion 110 is circular, with the central portion 5 located in the central region. The first top loading ring 1 is annular and connected to the central portion 5. The second top loading ring 2 is annular and concentrically disposed with and separated from the first top loading ring 1. The square resistive plate 3 is located between the first top loading ring 1 and the second top loading ring 2. The outer edge of the square resistive plate 3 is in contact with the inner edge of the second top loading ring 2. The outer edge of the first top loading ring 1 is separated from and isolated from the inner edge of the square resistive plate 3, forming an annular gap 4. The top loading portion 110 of this antenna is center-fed.

[0036] In this embodiment of the invention, the antenna uses a square resistive sheet 3 for distributed and concentrated loading, with the loading position selected in the middle of the disk of the top loading part 110. The first top loading ring 1 is for high-frequency radiating loading, and the second top loading ring 2 is for low-frequency radiating loading. By placing the square resistive sheet 3 between the high and low frequency radiating loading, the radiation impedance across the entire frequency band can be tuned. Specifically, in this embodiment of the invention, the antenna mainly absorbs the slightly higher frequency electromagnetic wave energy of the first top loading ring 1, while absorbing less of the low-frequency electromagnetic wave energy of the second top loading ring 2, thus ensuring the gain effect in the low-frequency band. At the same time, although more high-frequency electromagnetic wave energy is absorbed, the electrical length of the high-frequency band itself is guaranteed, and the high-frequency band gain is also guaranteed. Therefore, the gain of the antenna across the entire frequency band is guaranteed. The first top loading ring 1 is connected to the central part 5 of the center feed. A gap is opened between the first top loading ring 1 and the second top loading ring 2, which can be equivalent to a lumped loading capacitor, ensuring the effective electrical length of the low-frequency antenna of the second top loading ring 2. In this embodiment, the first top loading ring 1 and the second top loading ring 2 of the top loading part 110 are both annular, but are not limited to regular annular rings.

[0037] Figure 2 A three-dimensional structural schematic diagram of an antenna according to an embodiment of the present invention is shown. The antenna 100 of this embodiment includes a top loading portion 110, a monopole 50, a plurality of grounding posts 6 (four grounding posts 6 are provided in this embodiment), a second metal sleeve 7, a first metal sleeve 8, a metal ground plate 9, and a feed portion (…). Figure 2 (Not shown in the drawing). The top loading part 110 and the metal floor 9 are spaced apart and parallel to each other. One end of each grounding post 6 is set at the edge of the top loading part 110, and the other end of each grounding post 6 is connected to the metal floor 9. The monopole 50 is set below the top loading part 110, specifically directly below the center part 5 of the top loading part 110. The edge part of the top loading part 110 is connected to the metal floor 9 through four grounding posts 6. The four grounding posts 6 are arranged symmetrically in pairs. The projection points of two adjacent grounding posts 6 in the circular top loading part 110 are 90 degrees apart. Two grounding posts 6 that are spaced apart are respectively set at both ends of the diameter of the circular top loading part 110.

[0038] The first metal sleeve 8 is frustoconical and fits around the feed section, spaced apart from the plurality of grounding posts. The bottom end of the second metal sleeve 7 is connected to the top end of the first metal sleeve 8, and the bottom end of the first metal sleeve 8 is connected to the metal ground plate 9 and spaced apart from the grounding posts 6. The bottom end of the second metal sleeve 7 faces the top loading part 110, and the bottom area of ​​the first metal sleeve 8 is larger than that of the second metal sleeve 7. The bottom end of the central part 5 is connected downward to the feed and upward to the first top loading ring 1. The central part 5 is also connected to the feed. The metal ground plate 9 has a central opening (feed hole), and the feed end (top end) of the feed section extends to this opening to connect with the external feed. The metal ground plate 9 also serves as a fixing component for the antenna, and the entire antenna is fixed to the metal ground plate 9.

[0039] A monopole 50 is provided between the central part 5 and the metal floor 9. The monopole is connected below the central part 5. In this embodiment, the monopole 50 is a cone. The apex of the cone extends toward the metal floor 9. On the plane where the top loading part 110 is located, the projection of the apex of the monopole of the cone onto the plane coincides with the center of the top loading part 110.

[0040] The top loading section 110 can expand the antenna bandwidth and reduce the antenna height. Four grounding posts 6 are evenly distributed around the top loading section 110 and connect the top loading section 110 and the metal ground 9. By using the grounding posts 6 to short-circuit the top loading section 110 and the metal ground 9, the lateral dimension of the antenna is effectively reduced.

[0041] The second metal sleeve 7 and the first metal sleeve 8 serve as the gradient sleeves of the antenna. Each is a frustum-shaped structure with a gradually changing cross-sectional size and is made of conductive metal. The cross-sectional size of the first metal sleeve 8 gradually decreases from the bottom to the top (from bottom to top if the metal ground 9 is taken as the bottom). The bottom end of the first metal sleeve 8 is connected to the metal ground 9 and has a large area. The bottom edge of the first metal sleeve 8 is close to the grounding post 6 and the top end is close to the top loading part 110. The cross-sectional size of the second metal sleeve 7 gradually increases from the bottom to the top (from bottom to top if the metal ground 9 is taken as the bottom). The bottom end of the second metal sleeve 7 is connected to the top end of the first metal sleeve 8 and the top end of the second metal sleeve 7 faces the top loading part 110. The gradient sleeves can expand the antenna bandwidth and reduce the lateral size of the antenna. The first metal sleeve 8 is fitted around the power supply section, and the second metal sleeve 7 is fitted around the monopole. In other embodiments, the power supply section is extremely small and the monopole extends to the metal floor. It can be understood that both the first metal sleeve 8 and the second metal sleeve are fitted around the monopole.

[0042] The monopole 50 is a cone. The bottom surface of the cone is located below and connected to the center part 5 of the top loading part 110. The apex of the cone extends towards the metal floor 9 and connects to the bottom of the feed part. The top of the feed part passes through the feed hole at the center of the metal floor 9 to receive external feed signals, thereby providing power to the monopole. The second metal sleeve 7 and the first metal sleeve 8 are fitted around the monopole and the feed part.

[0043] The combined design of the second metal sleeve 7 and the first metal sleeve 8, compared to a single sleeve design, can further expand the bandwidth and facilitate overall matching and adjustment. The bottom end of the first metal sleeve 8 is directly connected to the metal ground plate 9, which can serve as grounding, expanding the antenna bandwidth and reducing the lateral size. The structure of the tapered sleeve can be equivalent to numerous grounding posts inclined relative to the ground plate, and its length is greater than that of a grounding post perpendicular to the ground plate. The effect of expanding the bandwidth is better than designing a vertical grounding post. Both the second metal sleeve 7 and the first metal sleeve 8 extend outward from the connection part, resulting in good impedance matching. At the same time, the design of the grounding post perpendicular to the ground plate in the outer layer restricts the lateral space of the inner layer. Considering the overall matching of the antenna, a tapered sleeve is designed in the inner layer. The lower edge of the tapered first metal sleeve 8 is as close as possible to but not in contact with the grounding post 6, making full use of the limited lateral space to expand the antenna bandwidth and reduce the lateral size. The feed part can also be a needle-shaped feed probe.

[0044] Figure 3 This diagram shows a top view of a simulated installation environment for an antenna according to an embodiment of the present invention. The antenna 100 of this embodiment is entirely embedded in a metal cavity 210, and the outer floor plate 200 is the actual metal floor of the antenna 100. The cavity 210 has dimensions of 460mm * 460mm * 135mm, the antenna 100 has a height of 125mm, and the center portion is one end of the feed section 10 (corresponding to a monopole). The antenna 100 is entirely fixed to the outer floor plate 100. The feed section 10 includes a top end and a bottom end. A feed hole is provided at the center of the metal floor plate 9. The top end of the feed section 10 passes through the feed hole of the metal floor plate 9 to receive external feed signals, and the bottom end connects to the apex of the conical monopole to transmit feed information to the monopole.

[0045] In the antenna 100 of the embodiment, the conical axis of the monopole, the central axis of the first metal sleeve 8, and the central axis of the second metal sleeve 7 coincide and are perpendicular to the plane where the top loading part 110 is located, with high symmetry, which facilitates simulation design.

[0046] Figure 4The diagram illustrates the port voltage standing wave ratio (VSWR) of an antenna according to an embodiment of the present invention. Within the effective frequency band of the antenna in this embodiment, the horizontal axis represents frequency, and the vertical axis represents VSWR. The VSWR across the entire frequency band of the antenna (i.e., the 0.3GHz-3GHz frequency range for UHF wireless communication) is less than 3, meeting engineering requirements. Specifically, the VSWR in the low-frequency band is less than 2.5, with the best portion being less than 1.5, indicating good low-frequency impedance matching performance of the antenna of this invention.

[0047] Figure 5 The diagram illustrates the minimum gain of the antenna at various frequencies at different elevation angles, according to an embodiment of the present invention. The horizontal axis represents frequency, and the vertical axis represents gain. The solid line with nodes represents the gain of the antenna at a horizontal elevation angle of 60° (thea = 30°), the dashed line represents the gain of the antenna at a horizontal elevation angle of 30° (thea = 60°), and the solid line represents the gain of the antenna at a horizontal elevation angle of 90°. In this embodiment of the invention, the antenna achieves a gain greater than -7 dBi at all frequencies in the horizontal plane (thea = 90°), with the low-frequency gain greater than -5 dBi, which is 2 dBi better than the high-frequency gain; at an elevation angle of 30° (thea = 60°), the minimum gain at all frequencies is greater than -2 dBi, with the low-frequency gain reaching 0 dBi; at an elevation angle of 60° (thea = 30°), the minimum gain at all frequencies is greater than -2.5 dBi, with the low-frequency gain greater than 0.5 dBi, which is 3 dBi better than the high-frequency gain.

[0048] In this embodiment of the invention, the antenna 100 is fixed relative to the metal ground plate 9, which is then connected to the actual installation environment. The antenna is embedded in a metal cavity. The top of the feed section 10 receives power from an external feed, and the bottom is connected to the center section 5. The center section 5 radiates high-frequency electromagnetic waves through the first top-loaded ring 1. The second top-loaded ring 2 radiates low-frequency electromagnetic waves from its outer edge after the feed is adjusted by the square resistive plate 3. The second metal sleeve 7, the first metal sleeve 8, and the top-loaded section 110 are associated with each other for radiation, thus expanding the bandwidth. The square resistive plate 3 can increase the electrical length of the second top-loaded ring 2, reduce radiation energy loss, and increase the gain of the corresponding low-frequency band radiation loading. The first top-loaded ring 1 radiates high-frequency electromagnetic waves from the gap 4. The energy of these high-frequency electromagnetic waves is absorbed by the square resistive plate 3 to reduce the radiation impedance of the second top-loaded ring 2 and increase the low-frequency band gain.

[0049] The aircraft provided by this invention uses the antenna provided by this invention, which has high overall gain in the ultra-high frequency band and ensures communication quality.

[0050] As described above, these embodiments of the present invention do not exhaustively cover all details, nor do they limit the invention to the specific embodiments described. Clearly, many modifications and variations can be made based on the above description. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to effectively utilize the invention and its modifications. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. An antenna, characterized in that, The antenna includes: a top loading portion, a metal ground plane, a monopole, and multiple grounding posts. The top loading portion and the metal ground plane are spaced apart and parallel to each other. One end of each grounding post is located at the edge of the top loading portion, and the other end of each grounding post is connected to the metal ground plane. The monopole is located below the top loading portion. The top loading portion is circular and includes: It is located at the center of the circular region; The first top-loading ring is connected to the central part; The second top loading ring is concentrically arranged with the first top loading ring but separate from it; The square resistive sheet is connected to the second top-loading ring, and is separated from the first top-loading ring to form an annular gap. The square resistive sheet is disposed between the first top loading ring and the second top loading ring, and is only connected to the second top loading ring. The first top loading ring is a high-frequency radiation loading ring, and the second top loading ring is a low-frequency radiation loading ring. The square resistive sheet is disposed between the two to distribute and concentrate the loading on the top loading part, tune the radiation impedance of the top loading part, improve the electrical length of the low-frequency band of the second top loading ring, and at the same time ensure the electrical length of the high-frequency band of the first top loading ring. The bottom of the central part is connected downward to the power supply and upward to the first top loading ring; The monopole is cone-shaped, with its base located below and connected to the center of the top loading portion, and its apex extending toward the metal floor.

2. The antenna according to claim 1, characterized in that, The projection of the vertex of the cone onto the plane where the top loading part is located coincides with the center of the top loading part.

3. The antenna according to claim 1, characterized in that, A feed hole is provided at the center of the metal floor, and the antenna further includes: The power supply section includes a top end and a bottom end. The top end of the power supply section passes through the power supply hole of the metal floor to receive external power supply signals, and the bottom end of the power supply section is connected to the cone apex of the monopole.

4. The antenna according to claim 3, characterized in that, The antenna also includes: The first metal sleeve is frustoconical and fits around the power supply section, and is spaced apart from the plurality of grounding posts.

5. The antenna according to claim 4, characterized in that, The first metal sleeve includes a bottom end and a top end. The bottom end of the first metal sleeve is connected to the metal floor, and the top end of the first metal sleeve is close to the top loading part. The cross-sectional dimension of the first metal sleeve gradually decreases from bottom to top.

6. The antenna according to claim 4, characterized in that, The antenna also includes: The second metal sleeve is frustoconical and fits around the monopole, and is located above the first metal sleeve and connected to the first metal sleeve.

7. The antenna according to claim 6, characterized in that, The second metal sleeve includes a bottom end and a top end. The bottom end of the second metal sleeve is connected to the top end of the first metal sleeve. The top end of the second metal sleeve is close to the top loading part. The cross-sectional dimension of the second metal sleeve gradually increases from bottom to top.

8. The antenna according to claim 6, characterized in that, The conical axis of the monopole, the central axis of the first metal sleeve, and the central axis of the second metal sleeve coincide and are perpendicular to the plane where the top loading part is located.

9. An aircraft, characterized in that, The aircraft includes the antenna as described in any one of claims 1-8.

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