An ultra-wideband edge-shooting Vivaldi phased array antenna suitable for conformal application on the surface of a flight platform fuel tank, flight platform fuel tank

Abstract

This invention discloses an ultra-wideband side-fire Vivaldi phased array antenna conformally to the surface of a flight platform fuel tank, and the flight platform fuel tank itself. The antenna body includes: a dielectric substrate layer conformally to the composite material surface of the flight platform fuel tank, and a metallic radiating layer and a feed network layer attached to the upper and lower surfaces of the dielectric substrate. The metallic radiating layer has a mirror-symmetrical bidirectional extension structure; it has gradually widening outward-facing slots and a circular resonant cavity on both sides, achieving a side-fire effect after conforming to the cylindrical surface. The feed network uses a microstrip line structure to provide parallel excitation signals to the metallic radiating structure. This invention is suitable for large-area array deployment on the surface of a flight platform, effectively solving the contradiction between low antenna profile, wide bandwidth, and high-gain side-fire while maintaining the aerodynamic shape.

Description

Technical Field

[0001] This invention relates to the field of conformal phased array antenna design technology, and in particular to an ultrawideband side-firing Vivaldi phased array antenna suitable for conformal design of a flight platform fuel tank surface and a flight platform fuel tank. Background Technology

[0002] In the design of conformal antennas for aircraft, there is a physical contradiction between low profile and high normal gain and ultra-wideband performance. Extremely low profile height leads to size constraints and an increased quality factor (Q factor), which can easily cause a simultaneous decrease in antenna element impedance matching bandwidth and normal radiation gain. How to balance ultra-wideband and high-gain side-fire radiation performance under low profile constraints is one of the current challenges in aircraft antenna design.

[0003] In recent years, with the rapid development of high-speed, stealth aircraft, the problems of traditional convex antennas, such as disrupting aerodynamic shape and increasing flight drag, have become increasingly apparent. "Conformal antenna" technology, which completely integrates the antenna with the airframe surface, has become one of the mainstream research trends. For some cylindrical high-speed aircraft platforms, to maximize the use of the outer shell surface space, researchers have begun to explore conformally arranging the antenna on the outside of the main fuel tank.

[0004] However, this conformal design of the fuel tank surface still faces significant challenges. On one hand, the fuel tank is typically filled with high-dielectric-constant liquid fuels such as kerosene, which reflect and absorb electromagnetic waves, worsening antenna impedance matching and causing beam deflection in the antenna radiation pattern. On the other hand, the limited usable height of the fuel tank surface severely restricts the height of the designed antenna profile. For example, the Vivaldi antenna, as a traveling-wave tapered groove structure, naturally possesses broadband side-firing advantages. However, in practical applications, when a traditional Vivaldi antenna is directly bent and attached to the surface of an aircraft's cylindrical fuel tank, it causes antenna impedance matching and radiation gain problems.

[0005] Chinese invention patent CN116231321A discloses an arbitrary cylindrical conformal metasurface conformal antenna and its design method. This scheme calculates the conformal compensation phase using optical path tracing, constructs a cylindrical lens structure with metasurface units, and uses a Vivaldi antenna as a feed source to achieve beam focusing and wavefront conversion. It can adapt to arbitrary cylindrical carriers generated by quadratic curves such as ellipses, hyperbolas, and parabolas. However, this scheme only uses the Vivaldi antenna as a feed source, rather than integrating it as a radiating element with the fuel tank. Its conformal structure does not consider the loading effects of kerosene medium and composite material shells, and uses a rigid 3D-printed structure, making it impossible to achieve flexible and tight conformal integration with the fuel tank of a flight platform. Furthermore, this scheme does not resolve the coupling contradiction between antenna bandwidth, gain, and conformal deformation under low profile constraints, making it difficult to directly apply to conformal scenarios on fuel tank surfaces.

[0006] In summary, the existing conformal antenna design for the surface of the fuel tank of a flight platform needs to effectively resolve the contradiction between low profile limitations and ultra-wideband, high normal gain radiation without compromising aerodynamic shape and size constraints. It also needs to compensate for the impact of complex media environments such as liquid fuel on antenna performance. Summary of the Invention

[0007] The purpose of this invention is to provide an ultra-wideband side-fire Vivaldi phased array antenna suitable for conformal firing on the surface of a flight platform fuel tank. Through a bidirectional Vivaldi structure with a central axis mirror symmetry, coupled with a one-to-two equal-amplitude in-phase feed, the antenna achieves ultra-wideband, high gain, and stable side-fire in the 0.6–5 GHz range even under the combined conditions of conformal firing on the fuel tank cylindrical surface, low profile constraints, and internal kerosene medium interference. This fundamentally solves the technical challenge of traditional conformal antennas being unable to simultaneously achieve low profile, wide bandwidth, high gain side-fire, and resistance to medium interference.

[0008] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows:

[0009] In a first aspect, the present invention discloses an ultrawideband side-fire Vivaldi phased array antenna suitable for conformal design of the fuel tank surface of a flight platform. The antenna element is a conformal microstrip Vivaldi structure, including a conformally bent dielectric substrate, and a metal radiating layer and a feed network layer attached to the upper and lower surfaces of the dielectric substrate.

[0010] The metal radiation layer is a bidirectional extension structure with a central axis mirror symmetry. Both sides are provided with a gradually changing horn-shaped opening slot formed by a smooth transition of an exponential curve. A circular resonant cavity is set at the narrow end connection of the gradually changing horn-shaped opening slot. After the metal radiation layer is conformally attached to the fuel tank cylindrical surface of the flight platform, both sides of the gradually changing horn-shaped opening slot face the same free space to achieve stable side radiation across the entire frequency band.

[0011] The power supply network layer is a one-to-two equal-amplitude in-phase microstrip power supply network, which uses a parallel excitation method to provide equal-amplitude in-phase excitation signals to the symmetrical radiation structures on both sides of the metal radiation layer.

[0012] Furthermore, the dielectric substrate is made of a high-frequency flexible dielectric material and is conformally attached to the outer surface of the flight platform's fuel tank;

[0013] The thickness of the dielectric substrate meets the conformal bending requirements of the fuel tank cylinder of the flight platform, and the selected material ensures that the antenna maintains stable impedance matching and radiation performance in the attached state.

[0014] Furthermore, the thickness of the dielectric substrate is 0.8 mm to 2.5 mm, and the relative permittivity is 2.0 to 3.0.

[0015] Furthermore, multiple identical antenna elements are arranged at equal intervals along the circumference of the cylindrical surface of the flight platform's fuel tank to form a conformal phased array.

[0016] Furthermore, the length and width of the metal radiating layer are limited by the conformal dimensions of the fuel tank cylinder of the flight platform and the antenna operating frequency band; the width of the narrow-end coupling slot of the tapered horn-shaped opening slot is limited by the antenna impedance matching requirements; the diameter of the circular resonant cavity is limited by the antenna resonant frequency and the slot line coupling effect requirements, so as to ensure that the antenna achieves ultra-wideband side-firing radiation performance in a conformal state.

[0017] Furthermore, the power supply network layer includes:

[0018] The total input microstrip feed is located on the central axis of the antenna element and near the bottom of the antenna.

[0019] The first microstrip feed branch and the second microstrip feed branch are connected to the total input microstrip feed line and branch on both sides with the antenna central axis as the symmetrical axis.

[0020] And fan-shaped branches respectively set at the ends of the first microstrip feed branch and the second microstrip feed branch.

[0021] Furthermore, the first microstrip feed branch and the second microstrip feed branch have the same structure, both consisting of four sequentially connected gradient microstrip feed lines, namely the first feed line, the second feed line, the third feed line and the fourth feed line, and the connection between each feed line segment adopts a rounded chamfer structure; the fourth feed line is located at the end of the feed branch and forms a coupled feed with the slotted line structure of the metal radiation layer.

[0022] Furthermore, the first feeder line constitutes the starting section of the feeder branch, extending outward at an angle from the total input microstrip feeder line, and connecting to the second feeder line after being bent.

[0023] The width of the second feeder wire gradually changes along the inclined direction, and after being bent, it is connected to the third feeder wire;

[0024] The third feeder wire extends along the cylindrical surface of the fuel tank and gradually changes in width. Its end is bent and connected to the fourth feeder wire.

[0025] The fourth feed line is a narrow microstrip line that extends in the direction of the gradually flared slot, and its end is coupled to the slot line structure of the metal radiation layer for power feeding.

[0026] The fan-shaped stub is located on the outermost side of the power supply branch and is adjacent to the circular resonant cavity.

[0027] In a second aspect, the present invention discloses a flight platform fuel tank, the fuel tank comprising a central cylindrical cavity and a fuel tank outer shell;

[0028] The fuel tank shell is wrapped around the outside of the central cylindrical cavity; the ultra-wideband side-firing Vivaldi phased array antenna, as described above, is conformally attached to the outer surface of the fuel tank shell.

[0029] Furthermore, the radius of the central cylindrical cavity is 70mm to 80mm, and the interior is filled with kerosene medium; the outer shell of the fuel tank is a composite material layer with a thickness of 20mm to 30mm.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] First, the ultra-wideband side-firing Vivaldi phased array antenna and the flight platform fuel tank conformally adapted to the surface of the flight platform fuel tank of the present invention, through an innovative curved conformal layout, successfully compress the Vivaldi antenna element into the extremely low surface of the flight platform fuel tank. This optimization solves the problem of the low profile requirement of traditional normal-radiating ultra-wideband array antennas disrupting the aerodynamic shape of the flight platform, and realizes the design of an ultra-wideband high-gain normal-radiating array antenna within an installation space with extremely limited height.

[0032] Secondly, the ultra-wideband side-firing Vivaldi phased array antenna and the flight platform fuel tank of this invention, which are conformally compatible with the surface of the flight platform fuel tank, adopt a conformal design architecture with a mirror-symmetric configuration of dual Vivaldi elements. Through the spatially reversed arrangement of the two radiating elements, the conformal design achieves radiation gain compensation and superposition, obtaining high-gain side-firing radiation with a low profile. This symmetrical structure enhances energy focusing efficiency, effectively suppresses beam divergence and beam distortion in the ultra-wideband range, and ensures high directivity and stability of the main lobe pattern across the entire frequency band.

[0033] Third, the present invention relates to an ultra-wideband side-firing Vivaldi phased array antenna conforming to the surface of a flight platform fuel tank. It designs a one-to-two equal-amplitude in-phase microstrip feed network for the flight platform fuel tank. By using the one-to-two equal-amplitude in-phase feed network and end-matching technology, the parasitic reactance in the conformal surface is neutralized. This not only achieves efficient impedance matching in the 0.6-5GHz ultra-wideband, but also breaks the constraints of the fuel tank and composite dielectric material environment on the antenna impedance matching performance. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the overall structure of an ultrawideband side-firing Vivaldi phased array antenna suitable for conformal application to the surface of a flight platform fuel tank, as an example of the present invention.

[0035] Figure 2 This is an antenna array diagram of an example of the present invention;

[0036] Figure 3 This is a schematic diagram of the planar structure of the antenna element in an example of the present invention;

[0037] Figure 4 This is a simulation diagram of the reflection coefficient S11 in an example of the present invention;

[0038] Figure 5a The image shows the E-plane gain of the antenna element at 0.7 GHz.

[0039] Figure 5b The image shows the E-plane gain of the antenna element at 2.5 GHz.

[0040] Figure 5c The antenna element's E-plane gain is shown at 5 GHz.

[0041] Figure 6 This is a graph showing the gain of the antenna element as a function of frequency. Detailed Implementation

[0042] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention.

[0043] It should be noted that all directional indications in the embodiments of the present invention are only used to explain the relative positional relationship and movement of the components in a specific posture; if the specific posture changes, the corresponding directional indications will also change.

[0044] like Figure 1As shown, the present invention discloses an ultra-wideband side-firing Vivaldi phased array antenna suitable for the surface of a flight platform fuel tank. The antenna element is a conformal microstrip Vivaldi structure, including a conformally bent dielectric substrate 1, and a metal radiating layer 7 and a feed network layer attached to the upper and lower surfaces of the dielectric substrate 1.

[0045] The dielectric substrate 1 is made of a high-frequency flexible dielectric material and is conformally attached to the outer surface of the flight platform's fuel tank. The thickness of the dielectric substrate 1 meets the conformal bending requirements of the fuel tank's cylindrical surface, and the selected material ensures that the antenna maintains stable impedance matching and radiation performance in the attached state. The flexible dielectric substrate can maintain structural continuity during the conformal deformation of the curved surface, avoiding stress cracking and electromagnetic performance drift caused by the bending of the rigid substrate; the lower relative permittivity can reduce the disturbance of the kerosene medium inside the fuel tank on the antenna surface current and radiation field, suppress surface wave excitation and impedance mismatch, thereby ensuring that the antenna still has stable ultra-wideband and high-gain radiation characteristics in the conformal state.

[0046] Preferably, the dielectric substrate 1 has a thickness of 0.8 mm to 2.5 mm and a relative permittivity of 2.0 to 3.0. In this example, the dielectric substrate 1 is made of Rogers 5880 high-frequency flexible dielectric material. This material features low loss, low permittivity, and high flexibility, maintaining stable electromagnetic performance during conformal bending of a cylindrical surface. It also reduces the influence of the kerosene dielectric on antenna impedance matching, thus ensuring low dielectric loss under conformal bending conditions. The substrate has a thickness of 1.5 mm, a length of 470 mm, and a width of 45 mm, corresponding to 0.66 times the wavelength of the highest operating frequency, with a permittivity of 2.2.

[0047] The metal radiation layer 7 is a bidirectional extension structure with a central axis mirror symmetry. Both sides are provided with a gradually changing horn-shaped opening slot 12 formed by a smooth transition of an exponential curve. A circular resonant cavity 5 is provided at the narrow end connection of the gradually changing horn-shaped opening slot 12. After the metal radiation layer 7 is conformally attached to the fuel tank cylindrical surface of the flight platform, both sides of the gradually changing horn-shaped opening slot face the same free space to achieve stable side radiation across the entire frequency band.

[0048] The length and width of the metallic radiating layer are jointly determined by the conformal dimensions of the fuel tank cylinder of the flight platform and the antenna's operating frequency band; the width of the narrow-end coupling slot of the tapered horn-shaped opening is set according to the antenna's ultra-wideband impedance matching requirements; the diameter of the circular resonant cavity is configured based on the antenna's resonant point and the coupling strength of the slot line, enabling the antenna to achieve stable ultra-wideband side-firing radiation even in a curved conformal state. Figure 1As shown, the width W of the metal radiation layer 7 in this example is 45 mm and the length L is 465.5 mm. Both ends of the layer are provided with funnel-shaped openings 12 that are symmetrically distributed along the central axis and smoothly transitioned by an exponential curve. A circular resonant cavity 5 is provided at the narrow end connection of the funnel-shaped opening 12. The radius of the circular resonant cavity 5 is 13 mm.

[0049] Multiple identical antenna elements are arranged at equal intervals along the circumference of the cylindrical surface of the flight platform's fuel tank, forming a conformal phased array. In this example, such as... Figure 2 As shown, the central cylindrical cavity 2 is located at the very center of the antenna system, with a radius of 75 mm, and is filled with kerosene. The fuel tank outer shell 4 is located outside the central cylindrical cavity 2 and between it and the Vivaldi phased array antenna body, and is made of a composite material with a thickness of 25 mm. Because the antenna elements adopt a symmetrical bidirectional gradient groove line and an equal amplitude and phase feeding structure, they can still maintain stable side-firing radiation characteristics after conformal bending. The antenna elements are arranged in equal intervals on the cylindrical surface, which can ensure low coupling between elements and high array amplitude and phase consistency without changing the aerodynamic shape of the fuel tank, thus meeting the application requirements of broadband conformal phased arrays for flight platforms.

[0050] The feed network layer is a two-way equal-amplitude, in-phase microstrip feed network, which uses a parallel excitation method to provide equal-amplitude, in-phase excitation signals to the symmetrical radiating structures on both sides of the metallic radiating layer 7. The feed network layer is a two-way equal-amplitude, in-phase feed network, including: a total input microstrip feed line 6 located on the central axis of the antenna element and near the bottom of the antenna; a first microstrip feed branch and a second microstrip feed branch connected to the total input microstrip feed line 6 and branching on both sides with the central axis of the antenna as the symmetrical axis; and fan-shaped stubs 3 respectively located at the ends of the first microstrip feed branch and the second microstrip feed branch.

[0051] like Figure 3 As shown, the total size of the input microstrip feed line 6 in this example is 3.4 × 3 mm. 2The first microstrip feed branch is completely symmetrical to the second microstrip feed branch, so only the first microstrip feed branch is described here. The first microstrip line branch consists of four gradually changing feed lines: the first feed line 8, the second feed line 9, the third feed line 10, and the fourth feed line 11. The first feed line 8 is located at the initial branch segment of the input end one-to-two feed line, extending outward at an angle from the total input microstrip feed line. After bending, it connects to the second feed line 9, playing a preliminary impedance transformation and branching role. The second feed line 9 is smoothly connected to the first feed line 8, with a gradually changing width along the inclined direction. After bending, it connects to the third feed line 10, which is the main impedance transition section. The third feed line 10 is connected to the second feed line 9, extending along the direction of the fuel tank cylinder surface with a gradually changing width. Its end is bent and connected to the fourth feed line 11, which further adjusts the characteristic impedance. The fourth feed line 11 is located at the end of the feed branch, extending towards the gradually changing horn-shaped opening slot. Its end forms a coupled feed with the slot line structure of the metal radiation layer 7. The connections between the first feeder line 8, the second feeder line 9, the third feeder line 10, and the fourth feeder line 11 are all provided with a circular chamfer with a radius of 1 mm. The fan-shaped stub 3 is located on the outermost side of the feeder branch and is arranged adjacent to the circular resonant cavity.

[0052] Figure 4 The figures show the S-parameter curves of the ultra-wideband side-fire Vivaldi phased array antenna of this invention, and the S11 parameter curves of the antenna element in this embodiment. These curves visually demonstrate the impedance matching of the antenna. It is clearly seen from the figures that the mirror-symmetric Vivaldi antenna structure used in this invention, combined with a one-to-two feed network with fan-shaped metal stubs at the ends, successfully excites dense adjacent multimode resonances in the ultra-wideband, thus achieving excellent ultra-wideband characteristics. Simulation results show that the S11 of this antenna element in the 0.6GHz to 5.0GHz frequency band is basically less than -10dB, perfectly covering the design target frequency band.

[0053] like Figure 5a , Figure 5b , Figure 5c The E-plane radiation pattern shown demonstrates excellent directional side-firing and high-gain characteristics across a wide bandwidth of 0.6-5.0 GHz, thanks to the conformal design achieved through dual-element mirror symmetry. In the 0.7 GHz low-frequency band, the main beam provides wide-angle forward coverage, effectively overcoming the low-frequency radiation degradation and energy leakage problems easily caused by traditional low-profile conformal installations. As the operating frequency increases, the spatial coherent superposition effect of the array becomes apparent, resulting in a strong convergence of electromagnetic energy directly forward, transforming the high-frequency radiation pattern into a highly directional beam and significantly increasing the peak gain. Figure 6The figure shows the antenna element gain as a function of frequency. Overall simulation results demonstrate that this design not only successfully mitigates the radiation effects of the composite medium inside the aircraft's fuel tank on the antenna, but also maintains absolute stability in the main radiation direction across a very wide frequency band, perfectly meeting the stringent engineering requirements of modern high-speed flight platforms for long-distance, multi-band complex radio frequency missions.

[0054] The ultra-wideband side-fire Vivaldi phased array antenna designed in this invention achieves this by using a conformal mirror-symmetric design for two antenna elements, coupled with an equal-amplitude, in-phase feed network. It also employs a compact element size and modular architecture, making it suitable for large-area array deployment on flight platform surfaces. While maintaining aerodynamic shape, it effectively resolves the contradiction between low profile, wide bandwidth, and high-gain side-fire. Under the constraint of antenna size, it successfully overcomes the limitations of low profile, ultra-wide bandwidth, and high gain, while also possessing excellent aerodynamic conformality and strong resistance to liquid medium interference. Therefore, it has promising prospects in the future field of radar detection.

[0055] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0056] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A conformal ultrawideband side-firing Vivaldi phased array antenna suitable for the surface of a flight platform's fuel tank, characterized in that, The antenna element is a conformal microstrip Vivaldi structure, including a conformally bent dielectric substrate, and a metal radiating layer and a feed network layer attached to the upper and lower surfaces of the dielectric substrate. The metal radiation layer is a bidirectional extension structure with a central axis mirror symmetry. Both sides are provided with a gradually changing horn-shaped opening slot formed by a smooth transition of an exponential curve. A circular resonant cavity is set at the narrow end connection of the gradually changing horn-shaped opening slot. After the metal radiation layer is conformally attached to the fuel tank cylindrical surface of the flight platform, both sides of the gradually changing horn-shaped opening slot face the same free space to achieve stable side radiation across the entire frequency band. The power supply network layer is a one-to-two equal-amplitude in-phase microstrip power supply network, which uses a parallel excitation method to provide equal-amplitude in-phase excitation signals to the symmetrical radiation structures on both sides of the metal radiation layer.

2. The ultra-wideband side-firing Vivaldi phased array antenna suitable for conformal application to the surface of a flight platform fuel tank, as described in claim 1, is characterized in that... The dielectric substrate is made of high-frequency flexible dielectric material and is conformally attached to the outer surface of the flight platform's fuel tank. The thickness of the dielectric substrate meets the conformal bending requirements of the fuel tank cylinder of the flight platform, and the selected material ensures that the antenna maintains stable impedance matching and radiation performance in the attached state.

3. The ultra-wideband side-firing Vivaldi phased array antenna suitable for conformal application to the surface of a flight platform fuel tank, as described in claim 2, is characterized in that... The dielectric substrate has a thickness of 0.8 mm to 2.5 mm and a relative permittivity of 2.0 to 3.

0.

4. The ultra-wideband side-firing Vivaldi phased array antenna suitable for conformal application to the surface of a flight platform fuel tank, as described in claim 1, is characterized in that... Multiple identical antenna elements are arranged at equal intervals along the circumference of the cylindrical surface of the flight platform's fuel tank, forming a conformal phased array.

5. The ultra-wideband side-firing Vivaldi phased array antenna suitable for conformal application to the surface of a flight platform fuel tank, as described in claim 1, is characterized in that... The length and width of the metal radiating layer are limited by the conformal dimensions of the fuel tank cylinder of the flight platform and the antenna operating frequency band; the width of the narrow end coupling slot of the tapered horn-shaped opening slot is limited by the antenna impedance matching requirements; the diameter of the circular resonant cavity is limited by the antenna resonant frequency and the slot line coupling effect requirements, so as to ensure that the antenna achieves ultra-wideband side-firing radiation performance in the conformal state.

6. The ultra-wideband side-firing Vivaldi phased array antenna suitable for conformal application to the surface of a flight platform fuel tank, as described in claim 1, is characterized in that... The power supply network layer includes: The total input microstrip feed is located on the central axis of the antenna element and near the bottom of the antenna. The first microstrip feed branch and the second microstrip feed branch are connected to the total input microstrip feed line and branch on both sides with the antenna central axis as the symmetrical axis. And fan-shaped branches respectively set at the ends of the first microstrip feed branch and the second microstrip feed branch.

7. The ultra-wideband side-firing Vivaldi phased array antenna suitable for conformal application to the surface of a flight platform fuel tank, as described in claim 6, is characterized in that... The first microstrip feed branch and the second microstrip feed branch have the same structure, both consisting of four sequentially connected gradient microstrip feed lines, namely the first feed line, the second feed line, the third feed line and the fourth feed line. The connection between each feed line segment adopts a rounded chamfer structure. The fourth feed line is located at the end of the feed branch and forms a coupled feed with the slotted structure of the metal radiation layer.

8. The ultra-wideband side-firing Vivaldi phased array antenna suitable for conformal application to the surface of a flight platform fuel tank, as described in claim 7, is characterized in that... The first feeder line forms the starting section of the feeder branch, extending outward at an angle from the main input microstrip feeder line, and connecting to the second feeder line after a bend; The width of the second feeder wire gradually changes along the inclined direction, and after being bent, it is connected to the third feeder wire; The third feeder wire extends along the cylindrical surface of the fuel tank and gradually changes in width. Its end is bent and connected to the fourth feeder wire. The fourth feed line is a narrow microstrip line that extends in the direction of the gradually flared slot, and its end is coupled to the slot line structure of the metal radiation layer for power feeding. The fan-shaped stub is located on the outermost side of the power supply branch and is adjacent to the circular resonant cavity.

9. A fuel tank for a flight platform, characterized in that, The fuel tank includes a central cylindrical cavity and a fuel tank outer shell; The fuel tank shell is wrapped around the outside of the central cylindrical cavity; the ultra-wideband side-fire Vivaldi phased array antenna as described in any one of claims 1-8 is conformally attached to the outer surface of the fuel tank shell.

10. The flight platform fuel tank according to claim 9, characterized in that, The central cylindrical cavity has a radius of 70mm to 80mm and is filled with kerosene. The outer shell of the fuel tank is a composite material layer with a thickness of 20mm to 30mm.

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