Airborne antennas and aircraft

Abstract

The application provides an airborne antenna and an aircraft. The airborne antenna comprises a dielectric substrate and two or more radiation sections arranged on the surface of the dielectric substrate and connected by impedance matching lines, each radiation section is in an axisymmetric structure, and the symmetry axes of different radiation sections have the same direction. The application improves the horizontal pattern distortion problem of the antenna in a high frequency band by adopting a radiation body segmentation design, and takes into account the gain of the antenna in the high frequency band on the basis of meeting the gain of the antenna in a low frequency band.

Description

Technical Field

[0001] This invention belongs to the field of communication technology, specifically relating to airborne antennas and aircraft. Background Technology

[0002] With the development of wireless communication technology, antennas, as an important wireless communication device, are being used more and more widely, and various types of antennas have emerged. Among them, airborne antennas are used to transmit and receive signals for various systems installed on aircraft, and their importance is self-evident. However, because airborne antennas require a wide bandwidth, and the large difference between high and low frequency wavelengths can easily lead to distortion of the horizontal radiation pattern of high-frequency gain, this has become another major challenge in the design of airborne antennas. Summary of the Invention

[0003] In view of this, the present invention provides an airborne antenna to solve the above problems.

[0004] According to a first aspect of the present invention, an airborne antenna is provided, comprising: a dielectric substrate and two or more radiating segments disposed on the surface of the dielectric substrate, the two or more radiating segments being connected by an impedance matching line, each radiating segment having an axisymmetric structure, and the axes of symmetry of different radiating segments having the same direction.

[0005] In some embodiments, the two or more radiation segments include a first radiation segment and a second radiation segment connected by the impedance matching line. The first radiation segment and the second radiation segment have the same axis of symmetry, and the radiation area of ​​the first radiation segment is larger than that of the second radiation segment. The remaining radiation segments are arranged symmetrically in pairs with the axis of symmetry of the first radiation segment and the second radiation segment as the central axis.

[0006] In some embodiments, the first and second radiating segments are both elongated and each radiating segment has outwardly protruding sharp corner structures at both ends, and the remaining radiating segments are cuboids or cubes. The two sharp corner structures of the first and second radiating segments are connected by the impedance matching line.

[0007] In some embodiments, the length and width of the first radiating segment are both greater than the length and width of the second radiating segment.

[0008] In some embodiments, the remaining radiation segments include a third radiation segment and a fourth radiation segment arranged symmetrically in pairs, and a fifth radiation segment and a sixth radiation segment arranged symmetrically in pairs. The third radiation segment and the fourth radiation segment are connected to the first radiation segment via the impedance matching line, and the fifth radiation segment and the sixth radiation segment are connected to the second radiation segment via the impedance matching line.

[0009] In some embodiments, the radiation areas of the third radiation segment and the fourth radiation segment are both greater than the radiation areas of the fifth radiation segment and the sixth radiation segment.

[0010] In some embodiments, the lengths of the third and fourth radiation segments are both equal to the length of the first radiation segment, and the lengths of the fifth and sixth radiation segments are both equal to the length of the second radiation segment.

[0011] In some embodiments, the lengths of the third radiation segment and the fourth radiation segment are both greater than the length of the first radiation segment plus the length of the impedance matching line between the first radiation segment and the second radiation segment.

[0012] In some embodiments, the third and fifth radiation segments located on one side of the first radiation segment have the same axis of symmetry, and the fourth and sixth radiation segments located on the other side of the first radiation segment have the same axis of symmetry.

[0013] According to a second aspect of the invention, an aircraft is provided, comprising the airborne antenna of any of the above claims.

[0014] The technical solution provided by this invention adopts a segmented radiator design, which improves the horizontal radiation pattern distortion problem of the antenna in the high-frequency band, and takes into account the antenna gain in the high-frequency band while satisfying the antenna gain in the low-frequency band.

[0015] Furthermore, the present invention also adopts a design method that conforms to the intelligent skin of the aircraft, which improves the antenna installation environment and achieves a wider operating bandwidth and a better horizontal radiation pattern. Attached Figure Description

[0016] 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:

[0017] Figure 1 This is a schematic diagram of an exemplary aircraft;

[0018] Figures 2a-2b These are a three-dimensional structural diagram and a plan view of the airborne antenna provided in the first embodiment of the present invention;

[0019] Figures 3a-3b These are a three-dimensional structural diagram and a plan view of the airborne antenna provided in the second embodiment of the present invention;

[0020] Figures 4a-4b These are a three-dimensional structural diagram and a plan view of the airborne antenna provided in the third embodiment of the present invention;

[0021] Figure 5a This is the horizontal radiation pattern of the airborne antenna in an embodiment of the present invention at 0.41f0;

[0022] Figure 5b This is the horizontal radiation pattern of the airborne antenna at 0.81f0;

[0023] Figure 5c This is the horizontal radiation pattern of the airborne antenna at 1.05f0;

[0024] Figure 5d This is the horizontal radiation pattern of the airborne antenna at 1.45f0;

[0025] Figure 5e This is the horizontal radiation pattern of the airborne antenna at 1.86f0;

[0026] Figure 6 This is a rendering of the airborne antenna provided by the present invention applied to the vertical tail of an aircraft;

[0027] Figure 7 This refers to the voltage standing wave ratio (VSWR) of the airborne antenna provided by this invention. Detailed Implementation

[0028] The present invention is described below based on embodiments, but the invention is not limited to these embodiments. In the detailed description of the invention below, certain specific details are described in detail. Those skilled in the art will fully understand the invention even without these details. To avoid obscuring the essence of the invention, well-known methods, processes, and procedures are not described in detail. Furthermore, the accompanying drawings are not necessarily drawn to scale.

[0029] Figure 1 This is a schematic diagram of an exemplary aircraft. As shown in the figure, the aircraft 10 includes a fuselage 12, wings 11, a vertical tail 13, and a horizontal tail 14. The airborne antenna can be disposed inside or integrated with the surface of at least one of the wings 11, vertical tail 13, and horizontal tail 14. When designing the aircraft, the airborne antenna and other aircraft components can be integrated into a single design. The type of airborne antenna is not limited; for example, a microstrip antenna can be used. It mainly includes a dielectric substrate and radiating elements disposed on the dielectric substrate. The dielectric substrate can be made of a material with high dielectric constant and low microwave loss, while the radiating elements can be made of a conductive material with high conductivity, good stability, and strong adhesion to the dielectric substrate.

[0030] Figures 2a-2b These are a three-dimensional structural diagram and a plan view of the airborne antenna provided in the first embodiment of the present invention. (Reference) Figures 2a-2bAs shown, the airborne antenna 20 includes a dielectric substrate 21 and a first radiating segment 22 and a second radiating segment 24 disposed on the upper surface of the dielectric substrate 21. The first radiating segment 22 and the second radiating segment 24 are connected by an impedance matching line 23. Both the first radiating segment 22 and the second radiating segment 24 have symmetrical structures and share the same axis of symmetry. As shown in the figure, the dashed line AA represents the axis of symmetry of the first radiating segment 22 and the second radiating segment 24. Continuing to refer to the figure, the first radiating segment 22 and the second radiating segment 24 are elongated strips with outwardly protruding pointed structures at both ends. The pointed structures of the first radiating segment 22 and the second radiating segment 24 are connected by the impedance matching line 23. Of course, the invention is not limited to this; each radiating segment can also be designed into other shapes, such as a rhombus, a cube, a cuboid, etc. The second radiating segment 22, the second radiating segment 24, and the matching line 23 can be etched using the same conductor layer covering the dielectric substrate 21. Therefore, the first radiating segment 22 and the second radiating segment 24 have the same height. As can be seen from the figure, the radiation area of ​​the first radiation segment 22 is greater than that of the second radiation segment 24, and the length and width of the upper surface of the first radiation segment 22 are greater than those of the upper surface of the second radiation segment 24 (since it is an irregular shape, the length and width here refer to the maximum length and width of the upper surface).

[0031] In an optional embodiment, a resistor 25 is further disposed at the top of the upper surface of the second radiating section 24, and the voltage standing wave ratio (VSWR) is adjusted via the resistor 25. The feed point of the airborne antenna can be selected at the top of the upper surface of the second radiating section 24, i.e., at the resistor 25, so that the maximum radiation direction of the airborne antenna will be from the first radiating section 22 toward the second radiating section 24. It can be understood that the radiation characteristics of the airborne antenna (including radiation patterns in the high-frequency and low-frequency bands) are related to the structural parameters (including radiating area, height, and geometry) of the first radiating section 22 and the second radiating section 24. The radiation characteristics can be considered as a function of the structural parameters. Therefore, the radiation performance can be affected by adjusting the structural parameters.

[0032] Verification has shown that the airborne antenna 20 can achieve low-frequency radiation performance and improve mid-to-high-frequency radiation performance through a shorter radiation segment, especially in improving the distortion problem of the horizontal radiation pattern.

[0033] Figures 3a-3b These are a three-dimensional structural diagram and a plan view of the airborne antenna provided in the second embodiment of the present invention. (Reference) Figures 3a-3bAs shown, the airborne antenna 30 includes a dielectric substrate 31 and multiple radiating segments disposed on the upper surface of the dielectric substrate 31. The multiple radiating segments are connected by impedance matching lines. Specifically, the multiple radiating segments include a first radiating segment 32 and a second radiating segment 34. The first radiating segment 32 and the second radiating segment 34 are elongated, and both ends of the first radiating segment 32 and the second radiating segment 34 include outwardly protruding sharp corner structures. The opposing sharp corner structures of the first radiating segment 32 and the second radiating segment 34 are connected by an impedance matching line 33. The multiple radiating segments also include a third radiating segment 35 and a fourth radiating segment 36 symmetrically arranged in pairs, and a sixth radiating segment 37 and a fifth radiating segment 38 symmetrically arranged in pairs. The third radiating segment 35 and the fourth radiating segment 36 are connected to the first radiating segment 32 via impedance matching lines 41 and 42, and the fifth radiating segment 38 and the sixth radiating segment 37 are connected to the second radiating segment 34 via an impedance matching line 39. As can be seen from the figure, each radiating segment exhibits an axisymmetric structure, and the axis of symmetry of each radiating segment points in the same direction (i.e., the Y-axis direction in the figure). The third radiating segment 35 and the fifth radiating segment 38 are located on one side of the first radiating segment 32 and the second radiating segment 34, and share the same axis of symmetry. The fourth radiating segment 36 and the sixth radiating segment 37 are located on the other side of the first radiating segment 32 and the second radiating segment 34, and also share the same axis of symmetry. As can be seen from the figure, the radiating area of ​​the first radiating segment 32 is larger than that of the second radiating segment 34. The length and width of the upper surface of the first radiating segment 32 are both greater than those of the upper surface of the second radiating segment 34. The radiating areas of the third radiating segment 35 and the fourth radiating segment 36 are respectively larger than those of the fifth radiating segment 38 and the sixth radiating segment 37. The length and width of the third radiating segment 35 and the fourth radiating segment 36 are both greater than those of the fifth radiating segment 38 and the sixth radiating segment 37. Furthermore, the lengths of the third radiating segment 35 and the fourth radiating segment 36 are both greater than the length of the first radiating segment 32 plus the length of the impedance matching line 33 between the first and second radiating segments. As can be seen from the figure, the third radiation segment 35 and the fifth radiation segment 38 are not in contact, and there is a distance between them, which makes the length of the fifth radiation segment 38 and the sixth radiation segment 37 much smaller than the length of the second radiation segment.

[0034] In an optional embodiment, the ratio of the longer radiation segment to the shorter radiation segment can be obtained experimentally. For example, in this embodiment, the ratio of the third radiation segment 35 to the fifth radiation segment 38 can be 3:1.

[0035] In an optional embodiment, a resistor 42 is also provided at the top of the upper surface of the second radiating section 34 to adjust the voltage standing wave ratio. The feed point of the airborne antenna can be selected at the top of the upper surface of the second radiating section 34, i.e., at the resistor 42, so that the maximum radiation direction of the airborne antenna will be from the radiating section 22 toward the radiating section 24.

[0036] In an optional embodiment, the plurality of radiating segments and the matching lines connecting the plurality of radiating segments can be formed by etching a conductor layer covering the upper surface of the dielectric substrate 31, so that the radiating segments are located on the same layer.

[0037] Figures 4a-4b These are a three-dimensional structural diagram and a plan view of the airborne antenna provided in the third embodiment of the present invention. (Reference) Figures 4a-4b As shown, the airborne antenna 50 includes a dielectric substrate 51 and multiple radiating segments disposed on the upper surface of the dielectric substrate 51. The multiple radiating segments are connected by impedance matching lines. Specifically, the multiple radiating segments include a first radiating segment 52 and a second radiating segment 54. The first radiating segment 52 and the second radiating segment 54 are elongated, and both ends of the first radiating segment 52 and the second radiating segment 54 include outwardly protruding sharp corner structures. The opposing sharp corner structures of the first radiating segment 52 and the second radiating segment 54 are connected by an impedance matching line 53. The radiating area of ​​the first radiating segment 52 is larger than that of the second radiating segment 54. The multiple radiating segments also include a third radiating segment 55 and a fourth radiating segment 56 symmetrically arranged in pairs, and a sixth radiating segment 58 and a fifth radiating segment 57 symmetrically arranged in pairs. The third radiating segment 55 and the fourth radiating segment 56 are connected to the first radiating segment 52 via an impedance matching line 59, and the fifth radiating segment 57 and the sixth radiating segment 58 are connected to the second radiating segment 54 via an impedance matching line 60. As can be seen from the figure, each radiation segment exhibits an axisymmetric structure, and the axis of symmetry of each radiation segment faces the same direction (i.e., the Y-axis direction in the figure). The third radiation segment 55 and the fifth radiation segment 57 are located on one side of the first radiation segment 52 and the second radiation segment 54, and have the same axis of symmetry. The fourth radiation segment 56 and the sixth radiation segment 58 are located on the other side of the first radiation segment 52 and the second radiation segment 54, and have the same axis of symmetry.

[0038] The difference from the second embodiment is that, in this embodiment, the length and width of the third radiation segment 55 are the same as those of the first radiation segment 52, the length and width of the fourth radiation segment 56 are the same as those of the first radiation segment 52, the length and width of the sixth radiation segment 58 are the same as those of the second radiation segment 54, and the length and width of the fifth radiation segment 57 are the same as those of the second radiation segment 54.

[0039] Can Figures 3a-3b and Figures 4a-4b The embodiment shown is considered a structural variation of the embodiment shown in Figure 2. Figures 3a-3b This is the optimal embodiment. By dividing the radiating sheet into multiple radiating segments, the radiation performance in the mid-to-high frequency band can be improved, especially the distortion problem of the horizontal radiation pattern.

[0040] The following is combined with Figures 5a-5eThis invention describes the technical effects of the airborne antenna provided in the embodiments of the present invention.

[0041] Figure 5a This is an example of the horizontal radiation pattern of an airborne antenna at 0.41f0, with a maximum gain of -15.9dBi and a minimum gain of -18.3dBi. Figure 5b This is the horizontal radiation pattern of the airborne antenna at 0.81f0, with a maximum gain of -3.1dBi and a minimum gain of -6.4dBi. Figure 5c This is the horizontal radiation pattern of the airborne antenna at 1.05f0, with a maximum gain of -0.2dBi and a minimum gain of -8.8dBi. Figure 5d This is the horizontal radiation pattern of the airborne antenna at 1.45f0, with a maximum gain of -1.6dBi and a minimum gain of -7.4dBi. Figure 5e This is the horizontal radiation pattern of the airborne antenna at 1.86f0, with a maximum gain of 1.3dBi and a minimum gain of -2.6dBi.

[0042] Existing airborne antennas exhibit good horizontal radiation characteristics in the low-frequency band, but in areas such as... Figures 5a-5e As shown, in the mid-to-high frequency band, the horizontal radiation pattern of the airborne antenna exhibits a large dip region. This large dip region indicates that the minimum gain at that frequency is very small. However, in the embodiments of the present invention, by using a shorter radiation band for electromagnetic radiation, it is possible to obtain... Figures 5a-5e The horizontal radiation patterns for various mid-to-high frequencies are shown. The minimum gain in these horizontal radiation patterns is greater than that of the corresponding antenna designs that do not use a shorter radiating segment, thereby improving the minimum gain of the antenna's horizontal radiation pattern at the corresponding frequencies.

[0043] Will Figures 3a-3b Comparing the horizontal radiation patterns of various mid-to-high frequencies with those of 4a-4b reveals that... Figures 3a-3b The horizontal radiation pattern of the airborne antenna shown is better than that of other antennas at mid-to-high frequencies. Figures 4a-4b The image shows the horizontal radiation pattern of the airborne antenna at mid-to-high frequencies. This is because, see [link to relevant documentation]. Figure 6 As shown, Figure 6 This is a rendering of the airborne antenna provided by the present invention applied to the vertical tail of an aircraft. 61 represents the aircraft carrier, used to carry, for example... Figures 3a-3b The airborne antenna 30 is shown. As can be seen from the figure,

[0044] The pointed structures of the first, third, and fourth radiating segments of the airborne antenna 30 are fixed to the aircraft carrier and are mainly used for electromagnetic wave radiation. The second, fifth, and sixth radiating segments are mainly used to fine-tune the radiation pattern of the airborne antenna. This fine-tuning helps to improve the distortion problem of the radiation pattern of the airborne antenna at mid-to-high frequencies. Since these radiating segments are at a relatively high height above the aircraft, they have little impact on the overall high-frequency radiation pattern of the airborne antenna and will not affect the radiation parameters of the airborne antenna at low-frequency frequencies.

[0045] It should also be noted that the airborne antenna provided by this invention can be conformally designed with the aircraft, for example, with... Figure 1 The vertical tail fin features a conformal design. A conformal airborne antenna can fit snugly against the aircraft surface, without adding extra air resistance, which is beneficial for the aircraft's aerodynamic performance design.

[0046] In summary, segmented design improves the horizontal radiation pattern distortion of the antenna in the high-frequency band, achieving both low-frequency and high-frequency gain for the airborne antenna. Based on this, multiple segmented radiating plates can be designed, and the shape, length, width, height, and other structural parameters of each segment can be adjusted in a simulation environment to obtain the optimal structural parameters.

[0047] In the above embodiments, the dielectric substrate can be made of FR-4 material with a thickness of 30 mil. The conductor layer covering the dielectric substrate can be made of conductive metal, such as copper with a thickness of 1 / 2 oz. The coupling resistor has a resistance of 100Ω and a power withstand capability of 100W. FR-4 is a designation for a flame-retardant material grade, meaning that the resin material must be able to self-extinguish after combustion. It is not a material name, but a material grade. Therefore, there are many types of FR-4 grade materials used in general circuit boards, but most of them are composite materials made of so-called four-function epoxy resin, filler, and glass fiber.

[0048] Furthermore, conformal design can be integrated with smart skin on the aircraft. For example, an airborne antenna can be positioned beneath the smart skin in a specific area of ​​the aircraft, making the smart skin a protective layer for the antenna. Alternatively, the airborne antenna can be embedded within the smart skin, making the smart skin an integral part of the antenna. This conformal design of the smart skin reduces the adverse effects of the aircraft's vertical metal structure and carbon fiber frame on the omnidirectional radiation of the conformal antenna.

[0049] Figure 7 This refers to the voltage standing wave ratio (VSWR) of the airborne antenna provided by this invention. Figure 7The figure shows the voltage standing wave ratio (VSWR) of the airborne antenna across the entire frequency band. As can be seen from the figure, the VSWR of the antenna is ≤3.5 across the entire frequency band and ≤3.0 in most frequency bands.

[0050] The present invention also provides an aircraft including the above-described airborne antenna.

[0051] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. For example, in practical applications, the functions of the above-described modules may be divided into functional structures different from those in the embodiments of the present invention, or several functional modules in the embodiments of the present invention may be merged and decomposed into different functional structures, depending on different needs. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Therefore, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims. Furthermore, it is clear that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units or devices recited in the system claims may also be implemented by a single unit or device through software or hardware.

[0052] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. For those skilled in the art, the present invention can be modified and varied in various ways. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of protection of the present invention.

Claims

1. An airborne antenna, characterized in that, include: A dielectric substrate and two or more radiating segments disposed on the surface of the dielectric substrate, wherein the two or more radiating segments include a first radiating segment and a second radiating segment connected by an impedance matching line. The two or more radiation segments further include: a third radiation segment and a fourth radiation segment symmetrically arranged in pairs with the axis of symmetry of the first radiation segment as the central axis; and a fifth radiation segment and a sixth radiation segment symmetrically arranged in pairs with the axis of symmetry of the second radiation segment as the central axis. The third and fourth radiation segments are connected to the first radiation segment via the impedance matching line, and the fifth and sixth radiation segments are connected to the second radiation segment via the impedance matching line. The fifth and sixth radiation segments are both axially symmetric structures, and the axes of symmetry of different radiation segments have the same direction. Wherein, the radiation area of ​​the first radiation segment is greater than that of the second radiation segment, and the radiation areas of the third and fourth radiation segments are both greater than those of the fifth and sixth radiation segments. The combination of the first, third, and fourth radiation segments is used for electromagnetic wave radiation, and the combination of the second, fifth, and sixth radiation segments is used to fine-tune the horizontal radiation pattern of the high-frequency band of the airborne antenna.

2. The airborne antenna according to claim 1, characterized in that, Both the first and second radiating segments are elongated and have outwardly protruding sharp corner structures at both ends. The third to sixth radiating segments are cuboids or cubes. The two sharp corner structures of the first and second radiating segments are connected by the impedance matching line.

3. The airborne antenna according to claim 1, characterized in that, The length and width of the first radiating segment are both greater than the length and width of the second radiating segment.

4. The airborne antenna according to claim 1, characterized in that, The lengths of the third and fourth radiation segments are both equal to the length of the first radiation segment, and the lengths of the fifth and sixth radiation segments are both equal to the length of the second radiation segment.

5. The airborne antenna according to claim 1, characterized in that, The lengths of the third and fourth radiating segments are both greater than the length of the first radiating segment plus the length of the impedance matching line between the first and second radiating segments.

6. The airborne antenna according to claim 1, characterized in that, The third and fifth radiation segments, located on one side of the first radiation segment, have the same axis of symmetry, and the fourth and sixth radiation segments, located on the other side of the first radiation segment, have the same axis of symmetry.

7. An aircraft, characterized in that, Includes the airborne antenna as described in any one of claims 1 to 6.

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