Array antenna

Abstract

The invention discloses an array antenna, and relates to the technical field of antennae, the array antenna 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 gaps, and each gap is communicated with the cavity and 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 is not overlapped with each gap; the low-frequency antenna feed source is used for transmitting electromagnetic wave signals to the low-frequency radiation units, and the high-frequency antenna feed source is used for outputting feed signals 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 work independently, and the overall performance of a communication system is ensured.

Description

Technical Field

[0001] The present application relates to the field of antenna technology, and in particular to an array antenna. Background Art

[0002] In the related art, a communication system usually adopts multiple transmission frequency bands. When a broadband antenna cannot fully cover the transmission frequency band, multiple single-frequency antennas are used accordingly.

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

[0004] The main purpose of this application is to propose an array antenna, aiming to solve the problem that multiple single-frequency antennas interfere with each other and restrict the overall performance of the communication system.

[0005] To achieve the above object, the present 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 radiation units, wherein a cavity is provided inside the conductive substrate, and each of the low-frequency radiation units is used to reflect electromagnetic wave signals;

[0006] A plurality of slots are provided on the upper surface of the conductive substrate, each slot is connected to the cavity, and each slot 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 radiation units, 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 radiation unit includes a connection structure and an open ring structure, and 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 gap, the lengths of the gaps are the same, and 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 gap.

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

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

[0013] In one embodiment, the thickness of the protruding portion of each of the low-frequency radiation units 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 radiation units is arranged in an array on the conductive substrate;

[0015] The slits extend along a first direction respectively and are arranged along a second direction, and the first direction intersects with the second direction.

[0016] In one embodiment, the distance between two adjacent low-frequency radiation units is one working wavelength;

[0017] At least part of the low-frequency radiation units and at least part of the gaps are arranged alternately.

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

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

[0020] The array antenna includes a low-frequency antenna feed, a high-frequency antenna feed, a conductive substrate, and a plurality of low-frequency radiating units. Since a cavity conductive substrate is provided inside the conductive substrate, a plurality of slots are provided on the upper surface of the conductive substrate, and each slot is connected to the cavity, and the high-frequency antenna feed outputs a feed signal to the conductive substrate, then each slot can be used as a high-frequency radiating unit respectively, and the high-frequency antenna adopts a slot leaky wave antenna, and each low-frequency radiating unit can reflect electromagnetic wave signals, and the low-frequency antenna feed transmits electromagnetic wave signals to each low-frequency radiating unit, then the low-frequency antenna adopts a flat reflective surface antenna, and the high-frequency antenna and the low-frequency antenna work simultaneously in the same aperture plane, which is conducive to the miniaturization and lightweight of the communication system. On this basis, since the orthographic projection of each low-frequency radiating unit on the conductive substrate does not overlap with each slot, and the low-frequency radiating unit can be only slightly higher than the slot, the mutual interference between the high-frequency antenna and the low-frequency antenna is very weak, so that the high-frequency antenna and the low-frequency antenna can work independently, thereby ensuring the overall performance of the communication system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

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

[0023] Figure 2 It is a schematic diagram of the cross-sectional structure of a conductive substrate in one embodiment of the present application;

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

[0025] Figure 4 Schematic diagram of the relationship between the geometric parameters and the reflection phase of the low-frequency radiation unit in one embodiment of the present application;

[0026] Figure 5 A schematic diagram of antenna directions of two types of antennas in the Ku band in an embodiment of the present application;

[0027] Figure 6 Schematic diagram of antenna directions of two types of antennas in the Ka band in one embodiment of the present application.

[0028] Description of Figure Numbers:

[0029] 11- low frequency antenna feed source, 12- conductive substrate, 13- low frequency radiation unit, 131- connection structure, 132- open ring structure, 1321- notch, 14- gap, 15- bracket, 16- feeding interface.

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

[0031] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

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

[0033] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0034] As described in the background art, in the related art, a communication system usually adopts multiple transmission frequency bands. When a broadband antenna cannot fully cover the transmission frequency band, multiple single-frequency antennas are used accordingly.

[0035] However, multiple antennas will inevitably increase the volume and weight of the entire communication system, and the interference between them will also restrict the overall performance of the system. In order to achieve the miniaturization and lightweight of multi-frequency communication systems, co-aperture antennas are a common solution. Co-aperture antennas are a type of antenna that allows multiple antennas with different frequency bands and different polarizations to work simultaneously in the same aperture plane. The co-aperture antenna solutions in related technologies mostly adopt the method of stacking up and down or nesting up and down. At the same time, in order to reduce the coupling and interference between the upper and lower antennas, some solutions will add a frequency selective surface (FSS). Although this stacking structure does not increase the aperture area, it increases the overall height of the antenna. Whether it is stacking up and down or nesting, it will cause the high and low frequency antennas to overlap in the vertical plane projection, thereby increasing the mutual influence between the high and low frequencies.

[0036] In order to solve the above problems, Figure 1 and Figure 2 As shown, the present 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 a plurality of low-frequency radiation units 13, wherein a cavity is provided inside the conductive substrate 12, and each low-frequency radiation unit 13 is a reflection structure, and each low-frequency radiation unit 13 is used to reflect electromagnetic wave signals. It should be noted that the low-frequency radiation unit 13 can adopt various types of structural forms, which can be determined according to actual needs.

[0037] The upper surface of the conductive substrate 12 is provided with a plurality of slits 14, each slit 14 is connected to the cavity, and each slit 14 serves as a high-frequency radiation unit. Each low-frequency radiation unit 13 is located on the upper surface of the conductive substrate 12, and the orthographic projection of each low-frequency radiation unit 13 on the conductive substrate 12 does not overlap with each slit 14. The low-frequency antenna feed 11 is used to transmit electromagnetic wave signals to each low-frequency radiation unit 13, and the 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 radiation surface of the low-frequency antenna feed 11 faces the upper surface of the conductive substrate 12. An opening can be provided on the edge of the conductive substrate 12 as a feed interface 16, and the high-frequency antenna feed outputs a feed signal to the conductive substrate 12 through the feed interface 16.

[0038] Among them, the conductive substrate 12 can be circular, and the material of the conductive substrate 12 can be metal. The gap 14 can be a linear gap 14. The low-frequency antenna feed 11 can be a horn-type feed. Further, the low-frequency antenna feed 11 can be a feed in the form of a conical horn feed, a rectangular horn feed, etc. Exemplarily, the low-frequency antenna feed 11 can be a conical horn feed.

[0039] In the case of low frequency, the size of the horn feed is relatively large, which 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 unit 13 in a wider frequency band, so that the electromagnetic wave signal emitted by the low-frequency antenna feed 11 is reflected by each low-frequency radiating unit 13, thereby realizing the emission of the low-frequency antenna signal.

[0040] It can be understood that a cavity is provided inside the conductive substrate 12, and the conductive substrate 12 can be regarded as a waveguide structure. After the high-frequency antenna feed source outputs a feed signal to the conductive substrate 12, a specific mode of electromagnetic wave propagation will exist inside the conductive substrate 12, such as the TM (transverse magnetic wave) mode. Since a plurality of slots 14 are provided on the upper surface of the conductive substrate 12, and each slot 14 is connected to the cavity, when the electromagnetic wave propagates along the conductive substrate 12, after the electromagnetic field energy is coupled to the slot 14, part of the energy will leak into the space outside the conductive substrate 12, forming an electromagnetic wave radiating outward. Therefore, the high-frequency antenna feed source and the conductive substrate 12 can cooperate to form a slot 14 leaky wave antenna, radiating high-frequency antenna signals outward.

[0041] Exemplarily, 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 can change the radiation direction and beam shape of the antenna by adjusting the geometric parameters of the slot 14.

[0042] In addition, the height of the low-frequency radiation unit 13 can be relatively low, and the low-frequency radiation unit 13 can be only slightly higher than the gap 14. On this basis, since the orthographic projection of each low-frequency radiation unit 13 on the conductive substrate 12 does not overlap with the gaps 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. The high-frequency antenna and the low-frequency antenna can work independently to ensure the overall performance of the communication system.

[0043] The array antenna comprises a low-frequency antenna feed 11, a high-frequency antenna feed, a conductive substrate 12 and a plurality of low-frequency radiation units 13. Since a cavity conductive substrate 12 is provided inside the conductive substrate 12, a plurality of slots 14 are provided on the upper surface of the conductive substrate 12, and each slot 14 is connected to the cavity, and the high-frequency antenna feed outputs a feed signal to the conductive substrate 12, then each slot 14 can be used as a high-frequency radiation unit respectively, and the high-frequency antenna adopts a slot 14 leaky wave antenna, and each low-frequency radiation unit 13 can reflect electromagnetic wave signals, and the low-frequency antenna feed 11 transmits electromagnetic wave signals to each low-frequency radiation unit 13, then the low-frequency antenna adopts a flat reflective surface antenna, and the high-frequency antenna and the low-frequency antenna work simultaneously in the same aperture plane, which is conducive to the miniaturization and lightweight of the communication system. On this basis, since the orthographic projection of each low-frequency radiating unit 13 on the conductive substrate 12 does not overlap with the gaps 14, and the low-frequency radiating unit 13 can be only slightly higher than the gap 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, thereby ensuring that the high-frequency antenna and the low-frequency antenna work independently, thereby ensuring the overall performance of the communication system.

[0044] In one embodiment, Figure 3 As shown, the low-frequency radiation unit 13 includes a connection structure 131 and an open ring structure 132 , and 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 may surround the connection structure 131, and the open ring structure 132 may include a structure of a circular opening type or a polygonal opening type. The connection structure 131 may be a connection structure 131 of various types, for example, the open ring structure 132 may be detachably connected to the conductive substrate 12 through the connection structure 131, and the specific connection method may be a snap connection, a threaded connection, or the like.

[0046] In the application, the open ring structure 132 is an electromagnetic resonance structure, and the geometric parameters of the open ring structure 132, such as the opening length and diameter, will affect the reflection phase of the electromagnetic wave. Specifically, the change in the opening length will change the inductance and capacitance characteristics of the open ring structure 132, thereby affecting its resonant frequency and reflection phase. When the opening length increases, the current path becomes longer and the inductance increases; at the same time, the capacitance at the opening will also change. According to the principle of the LC resonant circuit, the change in inductance and capacitance will reduce the resonant frequency, thereby causing a corresponding change in the reflection phase. The size of the diameter determines the size of the area enclosed by the open ring structure 132, thereby affecting the magnetic flux and inductance of the open ring structure 132. When the diameter increases, the area enclosed by the open ring structure 132 increases, the magnetic flux increases, and the inductance also increases accordingly. According to the law of electromagnetic induction, the change in inductance will affect the propagation characteristics of electromagnetic waves in 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 radiation units 13 often need to be able to provide at least one cycle, that is, a phase change of 0 to 360°.

[0048] In this embodiment, the low-frequency antenna adopts the form of a flat reflective surface. Since the distances from the low-frequency antenna feed source 11 to each location of the flat reflective surface are different, the phases are different. Therefore, it is necessary to design open rings of different sizes at different locations to produce corresponding compensation phases, so that the reflected electromagnetic waves can form the maximum gain at the specified direction angle, thereby improving the directivity and gain of the low-frequency antenna. The opening length and diameter of the open ring structure 132 will affect the reflection phase of the electromagnetic wave. The reflection phase at each location of the reflection surface can be adjusted by adjusting the opening length and diameter of the open ring structure 132. The flexibility is high, and it is easier to make the reflected electromagnetic waves form the maximum gain at the specified direction angle.

[0049] In one embodiment, if Figure 3 As shown, the open ring structure 132 has at least one gap 1321 , and the lengths of the gaps 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 gap 1321 .

[0050] It should be noted that the same lengths of the notches 1321 refer to the case where the open ring structure 132 has a plurality of notches 1321 , and the same lengths of the notches 1321 in the same open ring structure 132 .

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

[0052] Exemplarily, the diameter of the open ring structure 132 and the length of the gap 1321 corresponding to the reference reflection phase can be determined first, and the diameter of the open ring structure 132 and the length of the gap 1321 can be determined as the reference diameter and the reference length. Then, according to 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 the 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] As another example, a 360° phase cycle can be divided into equal parts according to fixed angular intervals, and then the parameters of the open ring structure 132 corresponding to each equally divided phase can be determined, and then the reflection phase corresponding to each position on the upper surface of the conductive substrate 12 can be determined, and the parameters of the open ring structure 132 corresponding to the reflection phase can be determined as the parameters of the open ring structure 132 corresponding to the closest equally divided phase, so as to simplify the process of determining the geometric parameters corresponding to the open ring structure 132 at each position.

[0054] In one embodiment, if Figure 3 As shown, the open ring structure 132 is a circular ring structure with four notches 1321 , and each arc portion of the open ring structure 132 is respectively connected to the connecting structure 131 , and the arc lengths of each notch 1321 are the same.

[0055] It can be understood that the open ring structure 132 is a circular ring structure with four notches 1321, and the open ring structure 132 is divided into four arc-shaped parts. Compared with a complete circular ring, the existence of these notches 1321 will change the electromagnetic properties of the structure, affect the response of the structure to electromagnetic waves, and thus affect the reflection phase of the low-frequency radiation unit 13 to the electromagnetic waves, and the same arc length of the notches 1321 means that the electromagnetic disturbances generated at the positions of each notch 1321 have similar characteristics, which is conducive to forming a relatively regular electromagnetic field distribution pattern. By connecting each arc-shaped part of the open ring structure 132 to the connecting structure 131 respectively, after the connecting structure 131 is connected to the upper surface of the conductive substrate 12, each arc-shaped part of the open ring structure 132 can also be 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 can be changed by controlling the open ring diameter d1 and the gap length d2. Generally, to achieve any desired phase, all open rings need to be able to provide at least one cycle, that is, a phase change of 0 to 360 degrees.

[0057] For example, taking the Ku band as an example, the central frequency of the Ku band is 12.5 GHz, and the relationship between the phase change and the size of the open ring structure 132 is shown in FIG. Figure 4 As shown. The first value in the bracket is the reflection phase provided by the open ring, and the second two values ​​are the diameter d1 and the opening length d2 of the open ring structure 132, in mm. The 360° phase of a cycle can be divided into equal parts at 45° intervals, as shown in Figure 4 It can be seen that the phase distribution has a total of 8 states, namely 0°, -45°, -90°, -135°, -180°, -225°, -270°, and -315°. Each state has a corresponding diameter d1 and an opening length d2. It can be found that the reflection phase is negatively correlated with the diameter of the open ring structure 132 and positively correlated with the length of the gap 1321. The actual required phase will be selected from these 8 states according to the nearest principle. It should be noted that dividing a cycle of 360° phase into equal parts at intervals of 45° is only an example of the present application. Other angles can also be used for equal division in the application, such as equal division at intervals of 30°.

[0058] By reasonably selecting the reflection phase at each location and its corresponding low-frequency radiation unit 13 (i.e., the open ring array element including the open ring structure 132), the reflection phase produces the maximum gain in the zenith direction (0° pointing angle), and the directional diagram of the antenna array is as follows: Figure 5 As shown in the figure, it can be seen that the Ku-band antenna produces the maximum gain (>23dBi) at a 0° pointing angle, and the high-frequency antenna element (i.e., slot 14) has very little effect on the low-frequency antenna pattern, and the two gain curves almost overlap. Similarly, the antenna pattern of the Ka-band is simulated with and without the open ring array element of the Ku-band antenna, and the results are shown in Figure 1. Figure 6 As shown in the figure, it can be found that the gain curves of the two are very consistent 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 portion that are connected to each other. The main body is located inside the open ring structure 132 and connected to the open ring structure 132 , and the threaded portion is threadedly connected to the upper surface of the conductive substrate 12 .

[0060] In application, a threaded hole may be provided on the upper surface of the conductive substrate 12, and a thread is provided on the outer surface of the threaded portion, so that the threaded portion can be threadedly connected to the threaded hole, thereby making the connection structure 131 screwed to 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, and the threaded portion is used to be threadedly connected to 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. Exemplarily, the connection structure 131 can be a bolt, the main body of the connection structure 131 is a nut, and the threaded portion is a screw, and these two parts are closely connected to form a complete connection component.

[0061] In one embodiment, if Figure 2 As shown, the thickness of the protruding portion of each low-frequency radiation 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 protruding portion of each low-frequency radiation 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, 1.0 mm. It should be noted that the thicknesses given in the above examples are only some examples of the present application and do not constitute a limitation on the thickness. In applications, the thickness of the protruding portion of each low-frequency radiation unit 13 relative to the upper surface of the conductive substrate 12 can also be other values.

[0062] Among them, the thickness of the low-frequency radiation unit 13 refers to the size of the low-frequency radiation unit 13 in a direction perpendicular to the upper surface of the conductive substrate 12. Exemplarily, in the case where the low-frequency radiation 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 radiation unit 13 relative to the upper surface of the conductive substrate 12 can be regarded as the thickness of the open ring structure 132, that is, the thickness of the open ring structure 132 is less than or equal to 1 mm. The thinner open ring structure 132 has its own characteristics in responding to electromagnetic waves. For example, when electromagnetic waves interact with the open ring, the thinner structure can make the distribution of the electromagnetic field inside it more uniform (the relatively thin thickness reduces the inhomogeneity of the internal electromagnetic field), which helps to accurately control electromagnetic characteristics such as the reflection phase.

[0063] It can be understood that when the thickness of the protruding portion of each low-frequency radiation unit 13 relative to the upper surface of the conductive substrate 12 is less than or equal to 1 mm, the low-frequency radiation unit 13 relative to the high-frequency radiation unit (slot 14) is less than or equal to 1 mm, and the mutual interference between the low-frequency antenna and the high-frequency antenna is very weak, which can ensure that each works independently and the overall performance of the communication system is guaranteed. In addition, since the thickness of the protruding portion of each low-frequency radiation unit 13 relative to the upper surface of the conductive substrate 12 is less than or equal to 1 mm, the size of the overall structure formed by the conductive substrate 12 and the multiple low-frequency radiation units 13 is small, which can effectively reduce the volume of the array antenna, thereby facilitating better integration of the array antenna into electronic devices.

[0064] In one embodiment, if Figure 1 As shown, each low-frequency radiation unit 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, and the first direction intersects the second direction.

[0065] The arrangement of the low-frequency radiation units 13 in an array on the conductive substrate 12 means that the multiple low-frequency radiation units 13 are neatly arranged in rows and columns on the upper surface of the conductive substrate 12 according to a certain rule. This arrangement is conducive to the overall control and optimization of electromagnetic radiation. The row direction of the array arrangement of the low-frequency radiation units 13 can be the second direction, and the column direction of the array arrangement of the low-frequency radiation units 13 can be the first direction.

[0066] The extension direction and arrangement of the slots 14 will change the distribution and propagation path of the electromagnetic field in the antenna structure. Extension along the first direction can better interact with the electric field or magnetic field of a specific mode in the conductive substrate 12 to achieve efficient energy transmission and radiation. Arrangement along the second direction can control the directionality of radiation. In addition, when the row direction of the array arrangement of each low-frequency radiation unit 13 can be the second direction, the column direction of the array arrangement of each low-frequency radiation unit 13 can be the first direction, and each slot 14 extends along the first direction and is arranged along the second direction, it is beneficial to stagger the low-frequency radiation unit 13 and the slot 14, so that the positive projection of each low-frequency radiation unit 13 on the conductive substrate 12 does not overlap with each slot 14, so that the mutual interference between the high-frequency antenna and the low-frequency antenna is very weak, thereby ensuring that the high-frequency antenna and the low-frequency antenna work independently, thereby ensuring the overall performance of the communication system.

[0067] In one embodiment, if Figure 1 As shown, the distance between two adjacent low-frequency radiation units 13 is one working wavelength. At least part of the low-frequency radiation units 13 and at least part of the gaps 14 are arranged alternately.

[0068] Among them, setting the spacing between two adjacent low-frequency radiation units 13 to an operating wavelength helps to enhance the directivity of low-frequency antenna radiation. When the spacing between adjacent low-frequency radiation units 13 is an operating wavelength, the electromagnetic waves radiated by them will produce constructive interference in a specific direction. Just like water waves, when multiple wave sources vibrate at appropriate intervals and phases, the peaks and troughs will overlap each other in certain directions, so that the energy is concentrated in these directions, thereby enhancing the radiation intensity of the entire system in that direction and improving the directivity. In addition, the sidelobe level can also be effectively reduced. Side lobes refer to smaller radiation beams that appear outside the main radiation direction. By setting the spacing between adjacent low-frequency radiation units 13 to an operating wavelength, the interference pattern of electromagnetic waves can be better controlled, so that most of the energy is concentrated in the main lobe direction, suppressing the generation of side lobes. This helps the array antenna to be suitable for application scenarios (such as directional communications, etc.) where the radiation direction is precisely controlled.

[0069] It can be understood that if the distance between two adjacent low-frequency radiation units 13 is one working wavelength, then the distance between two adjacent low-frequency radiation units 13 is small, and often only one gap 14 can be set between two adjacent low-frequency radiation units 13. Therefore, at least part of the low-frequency radiation units 13 can be arranged alternately with at least part of the gaps 14 to set the low-frequency radiation units 13 and the high-frequency radiation units on the same aperture plane. The low-frequency radiation units 13 and the high-frequency radiation units are compactly arranged, which is beneficial to reducing the size of the array antenna, thereby facilitating the miniaturization and lightweight of the communication system.

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

[0071] Each low-frequency radiation unit 13 and the conductive substrate 12 may be made of the same metal conductive material.

[0072] It can be understood that when the low-frequency radiation unit 13 and the conductive substrate 12 are made of the same material, the procurement, storage and management of materials can be unified and scaled, reducing the complex process and additional costs caused by the wide variety of materials. In terms of processing technology, the same material allows the same set of processing equipment, process flow and technical parameters to be used to manufacture each low-frequency radiation unit 13 and the conductive substrate 12. For example, in metal cutting, welding, surface treatment and other links, there is no need 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 radiation unit 13 is consistent with the material of the conductive substrate 12, so that the high-frequency antenna (slot 14 leaky wave antenna) and the low-frequency antenna (flat reflector antenna) can be processed and manufactured with the same material and process. For example, each low-frequency radiation unit 13 and the conductive substrate 12 can be manufactured using a metal material machining process. This is not only feasible in terms of technical implementation, but also conducive to achieving the goal of low-cost mass production.

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

[0075] The contour shape of the radiation surface of the low-frequency antenna feed source 11 and the contour shape of the conductive substrate 12 can be circular, polygonal, etc. For example, Figure 1 As shown, the low-frequency antenna feed 11 is a horn-type feed, the horn mouth of the horn-type feed facing the conductive substrate 12 is a radiation surface, and the horn mouth of the horn-type feed facing the conductive substrate 12 and the contours of the conductive substrate 12 are both circular.

[0076] It can be understood 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, and the same contour shape helps to 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 radiation surface of the low-frequency antenna feed 11 can better match the electromagnetic field of the conductive substrate 12. For example, if the low-frequency antenna feed 11 and the conductive substrate 12 are circular contours, the circular horn feed antenna radiates a circular pattern, and the circular reflection surface can just match it to achieve the most efficient reflection, thereby improving the overall efficiency of the antenna system. In terms of antenna beam forming, the same contour shape is conducive to controlling the shape and directivity of the beam. Due to the consistency of the shape of the radiation surface of the low-frequency antenna feed 11 and the conductive substrate 12, the propagation path and phase distribution of the electromagnetic wave in the reflector antenna are more regular.

[0077] The above description is only an exemplary embodiment of the present application and does not limit the patent scope of the present application. All equivalent structural changes made by using the contents of the present application specification and drawings under the technical concept of the present application, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present application.

Claims

1. An array antenna, characterized in that: The array antenna comprises: a low-frequency antenna feed, a high-frequency antenna feed, a conductive substrate and a plurality of low-frequency radiation units, wherein a cavity is provided inside the conductive substrate, and each of the low-frequency radiation units is used to reflect electromagnetic wave signals; A plurality of slots are provided on the upper surface of the conductive substrate, each slot is connected to the cavity, and each slot 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 radiation units, and the high-frequency antenna feed source is used to output a feed signal to the conductive substrate.

2. The array antenna according to claim 1, characterized in that: The low-frequency radiation unit includes a connection structure and an open ring structure, and the open ring structure is connected to the upper surface of the conductive substrate through the connection structure.

3. The array antenna according to claim 2, characterized in that: The open ring structure has at least one gap, and the lengths of the gaps are the same. 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 gap.

4. The array antenna according to claim 3, characterized in that: The open ring structure is a circular ring structure with four notches. Each arc portion of the open ring structure is connected to the connecting structure respectively, and the arc lengths of the notches are the same.

5. The array antenna according to claim 2, characterized in that: The connection structure comprises a main body and a threaded portion which are connected to each other. The main body is located inside the open ring structure and connected to the open ring structure. The threaded portion is threadedly connected to the upper surface of the conductive substrate.

6. The array antenna according to claim 1, characterized in that: 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.

7. The array antenna according to claim 1, characterized in that: The low-frequency radiation units are arranged in an array on the conductive substrate; The slits extend along a first direction respectively and are arranged along a second direction, and the first direction intersects with the second direction.

8. The array antenna according to claim 1, wherein: The distance between two adjacent low-frequency radiation units is one working wavelength; At least part of the low-frequency radiation units and at least part of the gaps are arranged alternately.

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

10. The array antenna according to any one of claims 1 to 9, characterized in that: The contour shape of the radiation surface of the low-frequency antenna feed source is the same as the contour shape of the conductive substrate.

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