array antenna

Abstract

The application discloses an array antenna, and relates to the technical field of antennas, which comprises a low-frequency antenna feed source, a high-frequency antenna feed source, a conductive substrate and a plurality of low-frequency radiation units, the conductive substrate is internally provided with a cavity, and each low-frequency radiation unit is used for reflecting an electromagnetic wave signal; the upper surface of the conductive substrate is provided with a plurality of slits, each slit is communicated with the cavity, and each slit serves as a high-frequency radiation unit; each low-frequency radiation unit is located on the upper surface of the conductive substrate, and the orthographic projection of each low-frequency radiation unit on the conductive substrate does not overlap with each slit; the low-frequency antenna feed source is used for emitting the electromagnetic wave signal to each low-frequency radiation unit, and the high-frequency antenna feed source is used for outputting a feed signal to the conductive substrate. The mutual interference between the high-frequency antenna and the low-frequency antenna of the array antenna is very weak, so that the high-frequency antenna and the low-frequency antenna can independently work, and the overall performance of a communication system is ensured.

Description

Technical Field

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

[0002] In related technologies, communication systems typically employ multiple transmission frequency bands. When it is difficult for a broadband antenna to fully cover the transmission frequency bands, multiple single-frequency antennas are used accordingly.

[0003] However, multiple antennas will inevitably increase the size and weight of the entire communication system, and the interference between them will also limit the overall performance of the communication system. Summary of the Invention

[0004] The main objective of this application is to propose an array antenna that aims to solve the problem of mutual interference between multiple single-frequency antennas, which restricts the overall performance of the communication system.

[0005] To achieve the above objectives, this application proposes an array antenna, which includes: a low-frequency antenna feed, a high-frequency antenna feed, a conductive substrate, and a plurality of low-frequency radiating elements. The conductive substrate has a cavity inside, and each of the low-frequency radiating elements is used to reflect electromagnetic wave signals.

[0006] The upper surface of the conductive substrate is provided with a plurality of slits, each of which is connected to the cavity and serves as a high-frequency radiation unit.

[0007] Each of the low-frequency radiation units is located on the upper surface of the conductive substrate, and the orthographic projection of each of the low-frequency radiation units on the conductive substrate does not overlap with each of the gaps.

[0008] The low-frequency antenna feed source is used to transmit electromagnetic wave signals to each of the low-frequency radiating elements, and the high-frequency antenna feed source is used to output a feed signal to the conductive substrate.

[0009] In one embodiment, the low-frequency radiating unit includes a connection structure and an open-ring structure, wherein the open-ring structure is connected to the upper surface of the conductive substrate through the connection structure.

[0010] In one embodiment, the open ring structure has at least one notch, all of which have the same length. The reflection phase of the low-frequency radiating element to the electromagnetic wave is negatively correlated with the diameter of the open ring structure and positively correlated with the length of the notch.

[0011] In one embodiment, the open ring structure is a circular ring structure with four notches, and each arc-shaped portion of the open ring structure is connected to the connecting structure, with each notch having the same arc length.

[0012] In one embodiment, the connection structure includes a main body and a threaded portion that are connected to each other. The main body is located inside the open ring structure and is connected to the open ring structure. The threaded portion is threadedly connected to the upper surface of the conductive substrate.

[0013] In one embodiment, the thickness of the protrusion of each low-frequency radiating unit relative to the upper surface of the conductive substrate is less than or equal to 1 mm.

[0014] In one embodiment, each of the low-frequency radiating units is arranged in an array on the conductive substrate;

[0015] Each of the aforementioned gaps extends along a first direction and is arranged along a second direction, wherein the first direction intersects the second direction.

[0016] In one embodiment, the spacing between two adjacent low-frequency radiating elements is one operating wavelength;

[0017] At least some of the low-frequency radiating elements are arranged alternately with at least some of the slots.

[0018] In one embodiment, the material of each of the low-frequency radiating units is the same as the material of the conductive substrate.

[0019] In one embodiment, the contour shape of the radiating surface of the low-frequency antenna feed is the same as the contour shape of the conductive substrate.

[0020] The aforementioned array antenna includes a low-frequency antenna feed, a high-frequency antenna feed, a conductive substrate, and multiple low-frequency radiating elements. Because the conductive substrate has a cavity, and its upper surface has multiple slots connected to the cavity, the high-frequency antenna feed outputs a feed signal to the conductive substrate. Each slot can then function as a high-frequency radiating element, and the high-frequency antenna employs a slotted leaky-wave antenna. Each low-frequency radiating element reflects electromagnetic signals, and the low-frequency antenna feed transmits electromagnetic signals to each low-frequency radiating element, thus employing a planar reflector antenna. The high-frequency and low-frequency antennas operate simultaneously within the same aperture plane, which is beneficial for miniaturization and weight reduction of the communication system. Furthermore, since the orthographic projection of each low-frequency radiating element onto the conductive substrate does not overlap with any of the slots, and the low-frequency radiating elements can be only slightly higher than the slots, the mutual interference between the high-frequency and low-frequency antennas is very weak. This ensures that the high-frequency and low-frequency antennas operate independently, thereby guaranteeing the overall performance of the communication system. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the array antenna structure in one embodiment of this application;

[0023] Figure 2 This is a schematic cross-sectional view of the conductive substrate in one embodiment of this application;

[0024] Figure 3 This is a schematic diagram of the planar structure of a low-frequency radiating unit in one embodiment of this application;

[0025] Figure 4 This is a schematic diagram showing the relationship between the geometric parameters of the low-frequency radiating element and the reflection phase in one embodiment of this application;

[0026] Figure 5 This is a schematic diagram of the antenna orientation of two types of antennas in the Ku band in one embodiment of this application;

[0027] Figure 6 This is a schematic diagram of the antenna orientation of two types of antennas in the Ka band in one embodiment of this application.

[0028] Explanation of icon numbers:

[0029] 11-Low-frequency antenna feed, 12-Conductive substrate, 13-Low-frequency radiating element, 131-Connection structure, 132-Open ring structure, 1321-Notch, 14-Gap, 15-Bracket, 16-Feed interface.

[0030] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0031] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0032] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0033] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0034] As described in the background section, in related technologies, communication systems typically employ multiple transmission frequency bands. When it is difficult for a broadband antenna to fully cover the transmission frequency bands, multiple single-frequency antennas are used accordingly.

[0035] However, multiple antennas inevitably increase the size and weight of the entire communication system, and interference between them can also limit the overall performance of the system. To achieve miniaturization and weight reduction of multi-frequency communication systems, co-aperture antennas are a common solution. A co-aperture antenna is an antenna type that allows multiple antennas with different frequency bands and polarizations to operate simultaneously within the same aperture plane. Co-aperture antenna solutions in related technologies often adopt a stacked or nested approach. At the same time, in order to reduce coupling and interference between upper and lower antenna layers, some solutions add a frequency selective surface (FSS). Although this stacked structure does not increase the aperture area, it increases the overall height of the antenna. Both stacking and nesting will cause overlap of the projections of high and low frequency antennas in the vertical plane, thus increasing the mutual influence between high and low frequencies.

[0036] To solve the above problems, such as Figure 1 and Figure 2 As shown, this application provides an array antenna, which includes: a low-frequency antenna feed 11, a high-frequency antenna feed (not shown), a conductive substrate 12, and multiple low-frequency radiating elements 13. The conductive substrate 12 has a cavity inside, and each low-frequency radiating element 13 is a reflective structure used to reflect electromagnetic wave signals. It should be noted that the low-frequency radiating elements 13 can adopt various structural forms, which can be determined according to actual needs.

[0037] The upper surface of the conductive substrate 12 has multiple slots 14, each slot 14 communicating with a cavity, and each slot 14 serves as a high-frequency radiating element. Each low-frequency radiating element 13 is located on the upper surface of the conductive substrate 12, and the orthographic projection of each low-frequency radiating element 13 onto the conductive substrate 12 does not overlap with any of the slots 14. A low-frequency antenna feed 11 is used to transmit electromagnetic wave signals to each low-frequency radiating element 13, and a high-frequency antenna feed is used to output a feed signal to the conductive substrate 12. In application, the low-frequency antenna feed 11 can be fixed by a bracket 15 so that the radiating surface of the low-frequency antenna feed 11 faces the upper surface of the conductive substrate 12. An opening can be provided at the edge of the conductive substrate 12 as a feed interface 16, through which the high-frequency antenna feed outputs a feed signal to the conductive substrate 12.

[0038] The conductive substrate 12 can be circular, and the material of the conductive substrate 12 can be metal. The slot 14 can be a linear slot 14. The low-frequency antenna feed 11 can be a horn-shaped feed. Further, the low-frequency antenna feed 11 can be a conical horn feed, a rectangular horn feed, or other similar feed forms. For example, the low-frequency antenna feed 11 can be a conical horn feed.

[0039] At low frequencies, horn-shaped feeds are relatively large and can provide better gain and directivity. The low-frequency antenna feed 11 adopts a horn feed, which can effectively radiate energy to each low-frequency radiating element 13 within a wide frequency band. Thus, the electromagnetic wave signal emitted by the low-frequency antenna feed 11 is reflected by each low-frequency radiating element 13, thereby realizing the transmission of low-frequency antenna signals.

[0040] It can be understood that since the conductive substrate 12 has a cavity inside, it can be considered a waveguide structure. After the high-frequency antenna feed outputs a feed signal to the conductive substrate 12, a specific mode of electromagnetic wave propagation, such as the TM (transverse magnetic wave) mode, will exist inside the conductive substrate 12. Because the upper surface of the conductive substrate 12 has multiple slots 14, each of which is connected to the cavity, when the electromagnetic wave propagates along the conductive substrate 12, the electromagnetic field energy couples to the slots 14, and some of the energy leaks into the space outside the conductive substrate 12, forming outward-radiating electromagnetic waves. Therefore, the high-frequency antenna feed and the conductive substrate 12 can cooperate to form a slot 14 leaky wave antenna, radiating high-frequency antenna signals outward.

[0041] For example, the high-frequency antenna in this embodiment can be a Variable Inclination Continuous Transverse Stub Antenna (VICTS) antenna, which forms a specific radiation pattern by applying a feed signal to the conductive substrate 12, and the radiation direction and beam shape of the antenna can be changed by adjusting the geometric parameters of the slot 14.

[0042] In addition, the height of the low-frequency radiating element 13 can be relatively low, and the low-frequency radiating element 13 can be only slightly higher than the gap 14. Based on this, since the orthographic projection of each low-frequency radiating element 13 on the conductive substrate 12 does not overlap with each gap 14, the mutual interference between the high-frequency antenna and the low-frequency antenna is very weak. There is no need to add an additional frequency selection surface, which can ensure that the high-frequency antenna and the low-frequency antenna work independently and ensure the overall performance of the communication system.

[0043] The aforementioned array antenna includes a low-frequency antenna feed 11, a high-frequency antenna feed 12, a conductive substrate 12, and multiple low-frequency radiating elements 13. Since the conductive substrate 12 has a cavity, and its upper surface has multiple slots 14 communicating with the cavity, the high-frequency antenna feed outputs a feed signal to the conductive substrate 12. Each slot 14 can then serve as a high-frequency radiating element, and the high-frequency antenna uses a slot 14 leaky-wave antenna. Each low-frequency radiating element 13 can reflect electromagnetic wave signals, and the low-frequency antenna feed 11 transmits electromagnetic wave signals to each low-frequency radiating element 13. Therefore, the low-frequency antenna uses a planar reflector antenna, and the high-frequency and low-frequency antennas operate simultaneously within the same aperture plane, which is beneficial for the miniaturization and weight reduction of the communication system. Based on this, since the orthographic projection of each low-frequency radiating element 13 onto the conductive substrate 12 does not overlap with each slot 14, and the low-frequency radiating element 13 can be only slightly higher than the slot 14, the mutual interference between the high-frequency antenna and the low-frequency antenna is very weak, and there is no need to add an additional frequency selective surface. This ensures that the high-frequency antenna and the low-frequency antenna can work independently, thereby ensuring the overall performance of the communication system.

[0044] In one embodiment, such as Figure 3 As shown, the low-frequency radiation unit 13 includes a connection structure 131 and an open ring structure 132. The open ring structure 132 is connected to the upper surface of the conductive substrate 12 through the connection structure 131.

[0045] The open ring structure 132 can surround the connecting structure 131. The open ring structure 132 can include structures with circular or polygonal openings. The connecting structure 131 can be of various types. For example, the open ring structure 132 can be detachably connected to the conductive substrate 12 through the connecting structure 131. The specific connection method can be a snap-fit ​​connection, a threaded connection, or other connection methods.

[0046] In applications, the open-loop structure 132 is an electromagnetic resonant structure. The geometric parameters of the open-loop structure 132, such as its opening length and diameter, affect the reflected phase of the electromagnetic wave. Specifically, changes in the opening length alter the inductance and capacitance characteristics of the open-loop structure 132, thus affecting its resonant frequency and reflection phase. When the opening length increases, the current path becomes longer, and the inductance increases; simultaneously, the capacitance at the opening also changes. According to the principle of LC resonant circuits, changes in inductance and capacitance lower the resonant frequency, leading to a corresponding change in the reflection phase. The diameter determines the area enclosed by the open-loop structure 132, thus affecting its magnetic flux and inductance. As the diameter increases, the area enclosed by the open-loop structure 132 increases, the magnetic flux increases, and the inductance also increases. According to the law of electromagnetic induction, changes in inductance affect the propagation characteristics of electromagnetic waves within the structure, thereby causing a change in the reflection phase.

[0047] It should be noted that, in order to achieve any desired phase, all low-frequency radiating elements 13 often need to be able to provide at least one cycle, i.e., a phase change of 0 to 360°.

[0048] In this embodiment, the low-frequency antenna adopts a planar reflector. Since the distance from the low-frequency antenna feed 11 to different points on the planar reflector varies, phase differences arise. Therefore, it is necessary to design open loops of different sizes at different locations to generate corresponding compensation phases, ultimately ensuring that the reflected electromagnetic wave achieves maximum gain at a specified azimuth angle, thereby improving the directivity and gain of the low-frequency antenna. The opening length and diameter of the open loop structure 132 both affect the electromagnetic wave reflection phase. Therefore, the reflection phase at different positions on the reflector can be adjusted by changing the opening length and diameter of the open loop structure 132, offering high flexibility and making it easier to ensure that the reflected electromagnetic wave achieves maximum gain at a specified azimuth angle.

[0049] In one embodiment, such as Figure 3 As shown, the open ring structure 132 has at least one notch 1321, and the lengths of the notches 1321 are the same. The reflection phase of the electromagnetic wave by the low-frequency radiation unit 13 is negatively correlated with the diameter of the open ring structure 132 and positively correlated with the length of the notch 1321.

[0050] It should be noted that the same length of each notch 1321 means that when the open ring structure 132 has multiple notches 1321, the length of each notch 1321 in the same open ring structure 132 is the same.

[0051] It is understandable that since the reflection phase of the low-frequency radiation unit 13 on electromagnetic waves is negatively correlated with the diameter of the open ring structure 132 and positively correlated with the length of the notch 1321, the reflection phase of the low-frequency radiation unit 13 can be adjusted based on this relationship, so as to design open rings of different sizes at different positions on the upper surface of the conductive substrate 12 to generate corresponding compensation phases.

[0052] For example, the diameter of the open ring structure 132 and the length of the notch 1321 corresponding to the reference reflection phase can be determined first. The diameter of the open ring structure 132 and the length of the notch 1321 are then determined as the reference diameter and reference length. Then, based on the relative relationship between the reflection phase corresponding to the open ring structure 132 and the reference reflection phase (whether the reflection phase is greater than or less than the reference reflection phase), the reference diameter and reference length are adjusted to determine the geometric parameters of the open ring structure 132. In this way, the geometric parameters of each open ring structure 132 can be determined.

[0053] For example, a 360° phase of a cycle can be divided into equal parts at fixed angular intervals. Then, the parameters of the open-loop structure 132 corresponding to each divided phase can be determined. Then, the reflection phase corresponding to each position on the upper surface of the conductive substrate 12 can be determined. The parameters of the open-loop structure 132 corresponding to the reflection phase can be determined as the parameters of the open-loop structure 132 corresponding to the closest divided phase, thereby simplifying the process of determining the geometric parameters corresponding to the open-loop structure 132 at each position.

[0054] In one embodiment, such as Figure 3 As shown, the open ring structure 132 is a circular ring structure with four notches 1321. Each arc-shaped part of the open ring structure 132 is connected to the connecting structure 131, and the arc length of each notch 1321 is the same.

[0055] It can be understood that the open-ring structure 132 is a ring structure with four notches 1321, thus dividing the open-ring structure 132 into four arc-shaped segments. Compared with a complete ring, the presence of these notches 1321 changes the electromagnetic properties of the structure, affecting the structure's response to electromagnetic waves, thereby affecting the reflection phase of electromagnetic waves by the low-frequency radiating unit 13. The same arc length of the notches 1321 means that the electromagnetic disturbances generated at each notch 1321 position have similar characteristics, which is conducive to forming a more regular electromagnetic field distribution pattern. By connecting each arc-shaped segment of the open-ring structure 132 to the connecting structure 131, after the connecting structure 131 is connected to the upper surface of the conductive substrate 12, each arc-shaped segment of the open-ring structure 132 is also fixed to the upper surface of the conductive substrate 12.

[0056] When the open-ring structure 132 is a circular ring structure with four gaps 1321, the reflection phase of the electromagnetic wave at this point can be changed by controlling the open-ring diameter d1 and the gap length d2. Typically, to achieve any desired phase, all open-rings must be able to provide at least one cycle, i.e., a phase change of 0 to 360°.

[0057] For example, taking the Ku band as an example, the center frequency of the Ku band is 12.5 GHz. The relationship between the phase change and the size of the open-loop structure 132 is shown in the figure below. Figure 4 As shown. The first value in parentheses is the reflection phase provided by the open-loop structure 132, and the latter two values ​​are the diameter d1 and opening length d2 of the open-loop structure 132, respectively, in mm. One period of 360° phase can be divided into equal intervals of 45°, by... Figure 4 It can be seen that the phase distribution has a total of 8 states: 0°, -45°, -90°, -135°, -180°, -225°, -270°, and -315°. Each state has a corresponding diameter d1 and opening length d2. It can be observed that the reflection phase is negatively correlated with the diameter of the opening ring structure 132 and positively correlated with the length of the notch 1321. The actual required phase will be selected from these 8 states according to the principle of proximity. It should be noted that dividing a 360° phase of a cycle into equal intervals of 45° is only an example of this application. In application, other angles can also be used for equal division, such as dividing it into equal intervals of 30°.

[0058] By rationally selecting the reflection phases at various locations and their corresponding low-frequency radiating elements 13 (i.e., the open-loop array elements including the open-loop structure 132), the reflection phases generate maximum gain in the zenith direction (0° pointing angle), and the radiation pattern of the antenna array is as follows. Figure 5 As shown, the Ku-band antenna produces maximum gain (>23 dBi) at a 0° pointing angle, and the high-frequency antenna element (i.e., slot 14) has very little impact on the low-frequency antenna pattern; the two gain curves almost overlap. Similarly, the antenna pattern of the Ka-band antenna is simulated with and without the open-loop element of the Ku-band antenna, and the results are as follows. Figure 6 As shown, the gain curves of both antennas match very well near the 0° and 180° pointing angles, which is also the main reference area for antenna performance.

[0059] In one embodiment, the connection structure 131 includes a main body and a threaded part that are connected to each other. The main body is located inside the open ring structure 132 and is connected to the open ring structure 132. The threaded part is threadedly connected to the upper surface of the conductive substrate 12.

[0060] In the application, a threaded hole can be provided on the upper surface of the conductive substrate 12, and the outer surface of the threaded portion is provided with threads, so that the threaded portion can be threadedly connected to the threaded hole, thereby allowing the connecting structure 131 to be screwed onto the upper surface of the conductive substrate 12. Since the main body is located inside the open ring and connected to the open ring structure 132, the main body is mainly responsible for establishing a connection with the open ring structure 132, while the threaded portion is used for threaded connection with the upper surface of the conductive substrate 12. The main body and the threaded portion work together to connect the conductive substrate 12 and the open ring structure 132. For example, the connecting structure 131 can be a bolt, with the main body of the connecting structure 131 being a nut and the threaded portion being a screw. These two parts are tightly connected to form a complete connecting component.

[0061] In one embodiment, such as Figure 2 As shown, the thickness of the protrusion of each low-frequency radiating unit 13 relative to the upper surface of the conductive substrate 12 is less than or equal to 1 mm. Exemplarily, the thickness of the protrusion of each low-frequency radiating unit 13 relative to the upper surface of the conductive substrate 12 can be 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, or 1.0 mm. It should be noted that the thicknesses given in the above examples are only partial examples of this application and do not constitute a limitation on the thickness. In applications, the thickness of the protrusion of each low-frequency radiating unit 13 relative to the upper surface of the conductive substrate 12 can also be other values.

[0062] The thickness of the low-frequency radiating unit 13 refers to its dimension in the direction perpendicular to the upper surface of the conductive substrate 12. For example, when the low-frequency radiating unit 13 includes a connecting structure 131 and an open-ring structure 132, since the connecting structure 131 is connected to the upper surface of the conductive substrate 12, the thickness of the protruding portion of the low-frequency radiating unit 13 relative to the upper surface of the conductive substrate 12 can be considered as the thickness of the open-ring structure 132, i.e., the thickness of the open-ring structure 132 is less than or equal to 1 mm. The thinner open-ring structure 132 has unique characteristics in its response to electromagnetic waves. For example, when an electromagnetic wave interacts with the open ring, the thinner structure allows for a more uniform distribution of the electromagnetic field within it (the relatively thin thickness reduces the non-uniformity of the internal electromagnetic field), which helps to precisely control electromagnetic properties such as the reflection phase.

[0063] It is understandable that if the thickness of the protrusion of each low-frequency radiating element 13 relative to the upper surface of the conductive substrate 12 is less than or equal to 1 mm, then the thickness of the low-frequency radiating element 13 relative to the high-frequency radiating element (slit 14) is less than or equal to 1 mm. This results in very weak mutual interference between the low-frequency and high-frequency antennas, ensuring independent operation and guaranteeing the overall performance of the communication system. Furthermore, since the thickness of the protrusion of each low-frequency radiating element 13 relative to the upper surface of the conductive substrate 12 is less than or equal to 1 mm, the overall structure formed by the conductive substrate 12 and the multiple low-frequency radiating elements 13 is relatively small. This effectively reduces the volume of the array antenna, facilitating better integration of the array antenna into electronic devices.

[0064] In one embodiment, such as Figure 1 As shown, each low-frequency radiating element 13 is arranged in an array on the conductive substrate 12. Each slot 14 extends along a first direction and is arranged along a second direction, with the first and second directions intersecting.

[0065] The array arrangement of low-frequency radiation units 13 on the conductive substrate 12 refers to the orderly arrangement of multiple low-frequency radiation units 13 in rows and columns on the upper surface of the conductive substrate 12 according to a certain pattern. This arrangement is beneficial for the overall control and optimization of electromagnetic radiation. The row direction of the array arrangement of each low-frequency radiation unit 13 can be a second direction, and the column direction of the array arrangement of each low-frequency radiation unit 13 can be a first direction.

[0066] The extension direction and arrangement of the slots 14 alter the distribution and propagation path of the electromagnetic field within the antenna structure. Extending along the first direction allows for better interaction with specific modes of electric or magnetic fields within the conductive substrate 12, achieving efficient energy transfer and radiation. Arranging along the second direction controls the directivity of the radiation. Furthermore, when the row direction of each low-frequency radiating element 13 array can be the second direction, and the column direction can be the first direction, with each slot 14 extending along the first direction and arranged along the second direction, it is advantageous for the low-frequency radiating elements 13 and slots 14 to be staggered. This ensures that the orthographic projection of each low-frequency radiating element 13 onto the conductive substrate 12 does not overlap with each slot 14, resulting in very weak mutual interference between the high-frequency and low-frequency antennas. This allows the high-frequency and low-frequency antennas to operate independently, thereby guaranteeing the overall performance of the communication system.

[0067] In one embodiment, such as Figure 1 As shown, the spacing between two adjacent low-frequency radiating elements 13 is one operating wavelength. At least some of the low-frequency radiating elements 13 and at least some of the gaps 14 are arranged alternately.

[0068] Setting the spacing between two adjacent low-frequency radiating elements 13 to one operating wavelength helps enhance the directivity of the low-frequency antenna radiation. When the spacing between adjacent low-frequency radiating elements 13 is one operating wavelength, the electromagnetic waves they radiate will produce constructive interference in a specific direction. Like water waves, when multiple wave sources vibrate with appropriate spacing and phase, wave crests and troughs will overlap in certain directions, concentrating energy in these directions and thus enhancing the radiation intensity of the entire system in that direction, improving directivity. Additionally, it can effectively reduce sidelobe levels. Sidelobes refer to smaller radiation beams that appear outside the main radiation direction. By setting the spacing between adjacent low-frequency radiating elements 13 to one operating wavelength, the interference mode of the electromagnetic waves can be better controlled, concentrating most of the energy in the main lobe direction and suppressing the generation of sidelobes. This helps the array antenna to be suitable for applications requiring precise control of the radiation direction (such as directional communication).

[0069] It is understood that if the spacing between two adjacent low-frequency radiating elements 13 is one operating wavelength, then the spacing between two adjacent low-frequency radiating elements 13 is relatively small. Often, only one gap 14 can be set between two adjacent low-frequency radiating elements 13. Therefore, at least some of the low-frequency radiating elements 13 can be staggered with at least some of the gaps 14 so that the low-frequency radiating elements 13 and the high-frequency radiating elements are set on the same aperture plane. The compact arrangement of the low-frequency radiating elements 13 and the high-frequency radiating elements is beneficial to reducing the size of the array antenna, thereby contributing to the miniaturization and weight reduction of the communication system.

[0070] In one embodiment, the material of each low-frequency radiating unit 13 is the same as the material of the conductive substrate 12.

[0071] Each low-frequency radiating unit 13 and the conductive substrate 12 can be made of the same metallic conductive material.

[0072] It is understandable that when the low-frequency radiating unit 13 and the conductive substrate 12 are made of the same material, the procurement, storage, and management of materials can be standardized and scaled up, reducing the complex processes and additional costs caused by the wide variety of materials. In terms of processing technology, the same material allows for the use of the same set of processing equipment, processes, and technical parameters to manufacture each low-frequency radiating unit 13 and conductive substrate 12. For example, in metal cutting, welding, and surface treatment, it is not necessary to frequently adjust equipment and process parameters to adapt to the characteristics of different materials, thereby improving processing efficiency and reducing processing costs.

[0073] In this embodiment, the material used for each low-frequency radiating element 13 is the same as the material used for the conductive substrate 12. This allows both the high-frequency antenna (slot 14 leaky antenna) and the low-frequency antenna (planar reflector antenna) to be manufactured using the same materials and processes. For example, both the low-frequency radiating element 13 and the conductive substrate 12 can be manufactured using metal machining processes. This is not only technically feasible but also facilitates achieving low-cost mass production.

[0074] In one embodiment, such as Figure 1 As shown, the outline shape of the radiating surface of the low-frequency antenna feed 11 is the same as the outline shape of the conductive substrate 12.

[0075] The outline shape of the radiating surface of the low-frequency antenna feed 11 and the outline shape of the conductive substrate 12 can be circular, polygonal, or other shapes. For example, as shown... Figure 1 As shown, the low-frequency antenna feed 11 is a horn-shaped feed, and the horn-shaped feed facing the conductive substrate 12 is the radiating surface. The horn-shaped feed facing the conductive substrate 12 and the outline of the conductive substrate 12 are both circular.

[0076] It is understandable that, from the perspective of electromagnetic coupling, the contour shape of the conductive substrate 12 directly affects the reflection effect on the low-frequency antenna feed 11. A consistent contour shape helps achieve more efficient and uniform electromagnetic energy transmission and coupling. When the low-frequency antenna feed 11 emits electromagnetic waves, the electromagnetic field distribution of the radiating surface of the low-frequency antenna feed 11 can be better matched with the electromagnetic field of the conductive substrate 12. For example, if the low-frequency antenna feed 11 and the conductive substrate 12 have circular contours, the circular horn feed antenna radiates a circular radiation pattern, which the circular reflecting surface can perfectly match, achieving the most efficient reflection and thus improving the overall efficiency of the antenna system. In terms of antenna beamforming, a consistent contour shape is beneficial for controlling the shape and directivity of the beam. Because the radiating surface of the low-frequency antenna feed 11 and the conductive substrate 12 have the same shape, the propagation path and phase distribution of electromagnetic waves in the reflector antenna are more regular.

[0077] The above description is merely an exemplary embodiment of this application and does not limit the patent scope of this application. Any equivalent structural transformations made based on the technical concept of this application and the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application.

Claims

1. An array antenna, characterized in that, The array antenna includes: a low-frequency antenna feed, a high-frequency antenna feed, a conductive substrate, and multiple low-frequency radiating elements. The conductive substrate has a cavity inside, and each of the low-frequency radiating elements is used to reflect electromagnetic wave signals. The upper surface of the conductive substrate is provided with a plurality of slits, each of which is connected to the cavity and serves as a high-frequency radiation unit. Each of the low-frequency radiation units is located on the upper surface of the conductive substrate, and the orthographic projection of each of the low-frequency radiation units on the conductive substrate does not overlap with each of the gaps. The low-frequency antenna feed source is used to transmit electromagnetic wave signals to each of the low-frequency radiating units, and the high-frequency antenna feed source is used to output a feed signal to the conductive substrate. The low-frequency radiation unit includes a connection structure and an open ring structure, wherein the open ring structure is connected to the upper surface of the conductive substrate through the connection structure; The connection structure includes a main body and a threaded part that are connected to each other. The main body is located inside the open ring structure and is connected to the open ring structure. The threaded part is threadedly connected to the upper surface of the conductive substrate. The open ring structure has at least one notch, and all the notches have the same length. The reflection phase of the electromagnetic wave by the low-frequency radiation unit is negatively correlated with the diameter of the open ring structure and positively correlated with the length of the notch. The thickness of the protruding portion of each low-frequency radiation unit relative to the upper surface of the conductive substrate is less than or equal to 1 mm.

2. The array antenna as described in claim 1, characterized in that, The open ring structure is a circular ring structure with four notches. Each arc-shaped part of the open ring structure is connected to the connecting structure, and the arc length of each notch is the same.

3. The array antenna as described in claim 1, characterized in that, Each of the low-frequency radiating units is arranged in an array on the conductive substrate; Each of the aforementioned gaps extends along a first direction and is arranged along a second direction, wherein the first direction intersects the second direction.

4. The array antenna as described in claim 1, characterized in that, The spacing between two adjacent low-frequency radiation units is one operating wavelength; At least some of the low-frequency radiating elements are arranged alternately with at least some of the slots.

5. The array antenna as described in claim 1, characterized in that, The material of each of the low-frequency radiation units is the same as the material of the conductive substrate.

6. The array antenna according to any one of claims 1 to 5, characterized in that, The outline shape of the radiating surface of the low-frequency antenna feed is the same as the outline shape of the conductive substrate.

Images