Array antenna

Abstract

The invention provides an array antenna. The array antenna comprises a reflecting plate; the first radiation units are arranged on the reflecting plate, and the number of the first radiation units is multiple; the first radiation units are arranged on the reflecting plate, the second radiation units are arranged on the reflecting plate, and the multiple first radiation units and the multiple second radiation units are distributed in an array mode; wherein the first radiation unit works in a first frequency band, the second radiation unit works in a second frequency band, and the lowest working frequency of the first frequency band is higher than the highest working frequency of the second frequency band. Through the structural design of the array antenna in the scheme, interference of parasitic radiation of the first radiation unit on working electromagnetic waves of the second radiation unit can be avoided, so that the phenomena of pattern distortion and isolation deterioration of the second radiation unit are avoided, and the performance of an antenna network is improved.

Description

Technical Field

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

[0002] With the increasing improvement of the global communication field construction, the mobile communication system now has multiple systems coexisting, including 2G / 3G / 4G / 5G. In order to reduce the network construction and operation and maintenance costs and consider the long-term evolvability of the network in the future, higher requirements are put forward for the broadband, miniaturization, and multi-mode of antennas, requiring an antenna to meet more network modes and cover all mobile communication frequency bands that are currently and may be used in the future. And it is required that the antenna has a small volume to facilitate the site selection of the base station and save space resources. Therefore, it is necessary to study the technology of multi-band, broadband, and miniaturized base station antennas.

[0003] For the traditional method of realizing antenna integration, one is to achieve it through structural stacking and assembly, that is, antennas with different frequency bands and different columns of the same frequency are realized by splicing left and right or up and down. However, no matter which splicing method is adopted, it will cause an increase in the antenna size, difficult construction, and high cost. The other is to use a relatively mature coaxial scheme for high and low frequencies to achieve, but the unit spacing of the coaxial scheme cannot be combined arbitrarily, and the size of the coaxial array cannot be further reduced. Especially in the integrated antenna of TDD+FDD multi-systems, the coaxial scheme is almost impossible to achieve.

[0004] Therefore, in the related art, radiation units similar to the positive cross and X-shaped are gradually used in base station antennas. Such radiation units can achieve flexible array formation and are easy to realize multi-antenna integration. However, due to the performance interference between radiation units of different frequency bands, the pattern is severely distorted and the isolation is poor, resulting in a decline in the antenna network performance. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide an antenna array, aiming to solve the problem of performance interference between radiation units of different frequency bands in the antenna array in the related art.

[0006] To solve the above technical problem, the present invention provides an array antenna, including:

[0007] A reflector;

[0008] A first radiation unit, arranged on the reflector, and a plurality of the first radiation units are provided; and,

[0009] A second radiation unit, arranged on the reflector, and a plurality of the second radiation units are provided. The plurality of first radiation units and the plurality of second radiation units are arranged in an array.

[0010] Among them, the first radiation unit operates in a first frequency band, the second radiation unit operates in a second frequency band, and the lowest operating frequency of the first frequency band is higher than the highest operating frequency of the second frequency band.

[0011] Optionally, the first radiation unit includes:

[0012] A first feeding component disposed on the reflector;

[0013] A coupling component disposed on the first feeding component, the coupling component having a plurality of coupling gaps distributed at intervals, and the plurality of coupling gaps being symmetrically distributed with respect to the central axis of the first radiation unit; and,

[0014] A plurality of first radiation arms, with each of the plurality of first radiation arms being correspondingly disposed in one of the plurality of coupling gaps, the length of the first radiation arm extending along the length direction of the corresponding coupling gap, and each of the first radiation arms being electrically insulated.

[0015] Optionally, the coupling component includes a plurality of coupling pair arms disposed on the first feeding component, the coupling pair arms having the coupling gaps, and the plurality of coupling pair arms being symmetrically distributed with respect to the central axis of the first radiation unit.

[0016] Optionally, the coupling pair arm includes two cross arms spaced apart and connected to the first feeding component at one end, with the coupling gap being provided between the two cross arms, and the length extension direction of the cross arms being parallel to the plane where the reflector is located.

[0017] Optionally, the cross section of the cross arm opposite to the first radiation arm is a flat structure, and the coupling surface of the cross arm close to the coupling gap is perpendicular to the plane where the reflector is located.

[0018] Optionally, the coupling component further includes a plurality of conductive dielectric members, and adjacent two coupling pair arms are connected by the conductive dielectric members.

[0019] Optionally, the first feeding component includes a first support arm vertically disposed on the reflector, the coupling component is disposed at the end of the first support arm far from the reflector, and the first support arm is provided with a choke slot, and the choke slot is disposed below the coupling gap.

[0020] Optionally, the length of the first radiation arm is λ / 4, and the length of the first support arm is λ / 4; where λ is the wavelength of the electromagnetic wave at the center frequency point of the first frequency band in air.

[0021] Optionally, the first radiation unit further includes a coaxial cable, the outer conductor of the coaxial cable is electrically connected to the corresponding first support arm, and the inner conductor is electrically connected to the relatively disposed first support arm.

[0022] Optionally, a loading sheet is disposed at one end of the first radiation unit away from the reflector.

[0023] Compared with the related art, an antenna array in the present invention has the beneficial effect that in the array antenna, since the first radiation unit operates in the first frequency band, the second radiation unit operates in the second frequency band, and the lowest operating frequency of the first frequency band is higher than the highest operating frequency of the second frequency band, through the structural design of the array antenna in this solution, the parasitic radiation of the first radiation unit can be avoided from interfering with the working electromagnetic wave of the second radiation unit, thereby avoiding the phenomena of pattern distortion and isolation deterioration of the second radiation unit and improving the performance of the antenna network. Description of the Drawings

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the related art, the following will briefly introduce the drawings required for the description of the embodiments or the related art. Obviously, the following drawings are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 is a schematic structural diagram of the array antenna provided by the embodiment of the present invention;

[0026] Figure 2 is a schematic structural diagram of the first radiation unit provided by an embodiment of the present invention;

[0027] Figure 3 is an assembly schematic diagram of the coupling component and the first feeding component provided by the embodiment of the present invention;

[0028] Figure 4 is a schematic structural diagram of the second radiation unit provided by the embodiment of the present invention;

[0029] Figure 5 is a schematic structural diagram of the first radiation unit provided by another embodiment of the present invention.

[0030] In the drawings, each reference numeral represents: 1, reflector; 2, first radiation unit; 21, first feeding component; 211, first support arm; 212, choke slot; 22, coupling component; 221, coupling gap; 222, cross arm; 223, conductive dielectric member; 23, first radiation arm; 24, coaxial cable; 3, second radiation unit; 31, second radiation arm; 32, second feeding component. Detailed Embodiments

[0031] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where like or similar reference numerals denote like or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0032] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "circumferential", "radial", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. These are only for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

[0033] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality of" means two or more unless otherwise specifically defined.

[0034] Embodiment:

[0035] Please refer to Figures 1 to 5 , an embodiment of the present invention provides an array antenna, including a reflector 1, a first radiation unit 2, and a second radiation unit 3. The first radiation unit 2 is disposed on the reflector 1, and there are a plurality of first radiation units 2; the second radiation unit 3 is disposed on the reflector 1, and there are a plurality of second radiation units 3. The plurality of first radiation units 2 and the plurality of second radiation units 3 are distributed in an array; wherein, the first radiation unit 2 operates in a first frequency band, the second radiation unit 3 operates in a second frequency band, and the lowest operating frequency of the first frequency band is higher than the highest operating frequency of the second frequency band.

[0036] In the array antenna, since the first radiating unit 2 works in the first frequency band, the second radiating unit 3 works in the second frequency band, and the lowest operating frequency of the first frequency band is higher than the highest operating frequency of the second frequency band, through the structural design of the array antenna in this scheme, the parasitic radiation of the first radiating unit 2 can be avoided from interfering with the working electromagnetic waves of the second radiating unit 3, thereby avoiding the distortion of the radiation pattern and deterioration of the isolation of the second radiating unit 3, and improving the performance of the antenna network.

[0037] It should be noted that when the first radiation unit 2 and the second radiation unit 3 work at the same time, if some frequencies of the second frequency band are multiples of some frequencies of the first frequency band, the first radiation unit 2 can be equivalent to a monopole antenna that can work in the second frequency band. The field excited by this equivalent monopole antenna when working is superimposed on the field excited by the second radiation unit 3 when working, which will distort the radiation pattern of the second radiation unit 3. To this end, through the structural design of the array antenna in this solution, the parasitic radiation frequency of the first radiation unit 2 falls outside the working frequency band of the second radiation unit 3, avoiding the parasitic radiation of the first radiation unit 2 from interfering with the working electromagnetic waves of the second radiation unit 3.

[0038] See also Figure 1 In one embodiment, two first radiation units 2 and two second radiation units 3 are provided, the two first radiation units 2 are arranged between the two second radiation units 3, and the two first radiation units 2 and the two second radiation units 3 are arranged in a row and are centrally symmetrically distributed.

[0039] See also Figure 2 , Figure 3 and Figure 5 The first radiation unit 2 includes a first feeding component 21, a coupling component 22 and a first radiation arm 23. The first feeding component 21 is arranged on the reflection plate 1; the coupling component 22 is arranged on the first feeding component 21, and the coupling component 22 has a plurality of coupling gaps 221 distributed at intervals, and the plurality of coupling gaps 221 are symmetrically distributed with the central axis of the first radiation unit 2 as the symmetry axis; there are a plurality of first radiation arms 23, and the plurality of first radiation arms 23 are arranged in a one-to-one correspondence in the plurality of coupling gaps 221, and the length of the first radiation arm 23 extends along the length direction of the corresponding coupling gap 221, and each first radiation arm 23 is electrically insulated. The first radiation unit 2 is an equivalent half-wave symmetrical oscillator, and the equivalent electrical length of the first radiation unit 2 can be changed by adjusting the size of the coupling component 22, so that the parasitic radiation interval of the first radiation unit 2 avoids the second frequency band of the second radiation unit 3, that is, the working frequency range of the first radiation unit 2 falls outside the second frequency band, so that the coupling between the first radiation unit 2 and the second radiation unit 3 is weakened, avoiding affecting the normal operation of the second radiation unit 3.

[0040] Generally, for a half-wave symmetric dipole, the electrical length of a single radiation arm is approximately λ / 4 (where λ is the wavelength of the electromagnetic wave in air at the center frequency of the operating frequency of the half-wave symmetric dipole), the electrical length of the feeding structure is approximately λ / 4, and the sum of the lengths of the radiation arm and the feeding structure is approximately λ / 2, which is equivalent to a deformed half-wave symmetric dipole placed vertically. When the wavelengths corresponding to some frequency points in the second frequency band are in a multiple relationship with the size of the equivalent half-wave symmetric dipole, an induced current in the second frequency band will be induced on the equivalent half-wave symmetric dipole, thereby generating parasitic radiation. The parasitic radiation electromagnetic wave is superimposed on the electromagnetic wave radiated normally by the second radiation unit 3, causing distortion of the radiation pattern of the second radiation unit 3 and serious degradation of performance.

[0041] It should be understood that in the present invention, the first feeding component 21 and the first radiation arm 23 are connected by the coupling component 22. Thus, by adjusting the size of the coupling component 22, the parasitic radiation interval of the above equivalent half-wave symmetric dipole can be avoided from the operating frequency band of the second radiation unit 3, thereby weakening the coupling between the two and preventing the normal operation of the second radiation unit 3 from being affected. Moreover, compared with changing the material sizes of the first radiation arm 23 and the first feeding component 21, changing the material size of the coupling component 22 can reduce the greater impact on the first radiation unit 2 itself, so that the first radiation unit 2 can operate better in the first frequency band.

[0042] It should be noted that according to the electromagnetic wave mirror principle, the electrical length of the first radiation unit 2 is equivalent to the sum of the electrical length of the first radiation arm 23, the electrical length of the first feeding component 21, and the electrical length of their images on the reflector 1. That is, the equivalent electrical length of the first radiation unit 2 is twice the sum of the electrical lengths of the first radiation arm 23 and the first feeding component 21. When the equivalent electrical length of the first radiation unit 2 is 0.5 times the center wavelength of the first frequency band, electromagnetic waves with a frequency in the first frequency band can be transmitted and received.

[0043] Please refer to Figure 2 , in some embodiments, one ends of the first radiation arms 23 are commonly connected together, and the other ends extend along the length direction of the corresponding coupling gap 221, and the first radiation arms 23 are sheet-shaped.

[0044] Please refer to Figure 5 , in some embodiments, the first radiation arm 23 can be a sheet metal thin plate or a metal round bar that is disconnected in the middle.

[0045] Please refer to Figure 2 , Figure 3 and Figure 5, the coupling component 22 includes a plurality of coupling pair arms disposed on the first feeding component 21. The coupling pair arms are provided with coupling gaps 221, and the plurality of coupling pair arms are symmetrically distributed with respect to the central axis of the first radiation unit 2. A plurality of first radiation arms 23 are respectively disposed in the coupling gaps 221 of the plurality of coupling pair arms to ensure that the first radiation unit 2 has a centrosymmetric structure and satisfies that the first radiation unit 2 is an equivalent half-wave symmetric oscillator.

[0046] According to actual needs, in a specific example, there are four first radiation arms 23, and the four first radiation arms 23 are connected into a cross shape; there are four coupling pair arms, and the four coupling pair arms form a cross structure at one end of the first feeding component 21 away from the reflector 1. The four first radiation arms 23 are respectively disposed in the coupling gaps 221 of the four coupling pair arms.

[0047] Please refer to Figure 2 、 Figure 3 and Figure 5 , the coupling pair arms include two cross arms 222 that are spaced apart and connected to the first feeding component 21 at one end. A coupling gap 221 is provided between the two cross arms 222. The length extension direction of the cross arms 222 is parallel to the plane where the reflector 1 is located. The size of the coupling component 22 can be adjusted by changing the length and width of the cross arms 222. Among them, the coupling gap 221 is usually small, and the optimal value of the size of the coupling gap 221 can be determined through simulation or actual debugging.

[0048] Please refer to Figure 1 、 Figure 3 and Figure 5 , the cross section of the cross arm 222 opposite to the first radiation arm 23 is a flat structure. The coupling surface of the cross arm 222 close to the coupling gap 221 is perpendicular to the plane where the reflector 1 is located, which can reduce the influence of the first radiation unit 2 on other radiation units and enhance the coupling efficiency at the same time. Among them, the placement direction of the cross arm 222 is perpendicular to the plane where the reflector 1 is located.

[0049] Please refer to Figure 2 、 Figure 3 and Figure 5 , the coupling component 22 further includes a plurality of conductive dielectric parts 223. Adjacent coupling pair arms are connected by the conductive dielectric parts 223. Both ends of the conductive dielectric parts 223 are respectively connected to the cross arms 222 of the adjacent coupling pair arms, so that the conductive dielectric parts 223 and the cross arms 222 are connected to form a loop, which can play a role in impedance matching. Among them, the conductive dielectric parts 223 and the cross arms 222 can be integrally formed by die casting.

[0050] Please refer to Figure 1 、 Figure 2 and Figure 3, the first feeding component 21 includes a first support arm 211 vertically arranged on the reflector 1. The coupling component 22 is arranged at one end of the first support arm 211 away from the reflector 1. The first support arm 211 is provided with a choke slot 212, and the choke slot 212 is arranged below the coupling gap 221. Among them, the coupling pair arms are arranged at one end of the first support arm 211 away from the reflector 1, and the two cross arms 222 of the same coupling pair arm are respectively arranged on the opposite sides of the choke slot 212 of the first support arm 211, and the cross arms 222 can play a role of coupling and feeding the first support arm 211.

[0051] The length of the first radiation arm 23 is λ / 4, and the length of the first support arm 211 is λ / 4; where λ is the wavelength of the electromagnetic wave at the center frequency point of the first frequency band in the air, and the material of the first radiation arm 23 can be copper-clad pcb or sheet metal.

[0052] Please refer to Figure 2 and Figure 5 , the first radiation unit 2 further includes a coaxial cable 24. The outer conductor of the coaxial cable 24 is electrically connected to the corresponding first support arm 211, and the inner conductor is electrically connected to the relatively arranged first support arm 211, so that the first support arm 211 is fed through the coaxial cable 24. Among them, the other end of the coaxial cable 24 is electrically connected to the feeding network on the reflector 1.

[0053] According to actual needs, there are four first support arms 211, and the four support arms are symmetrically distributed at the center of the first radiation unit 2, and the two polarized coaxial cables 24 are fed in a positive staggered manner in the upper and lower spaces.

[0054] A loading piece is arranged at one end of the first radiation unit 2 away from the reflector 1. By adjusting the height and size of the loading piece, the electrical performance of the first radiation unit 2 is optimized.

[0055] The first radiation unit 2 can be directly connected to the reflector 1 through a metal connector, or indirectly connected to the reflector 1 through a non-metal connector.

[0056] Please refer to Figure 1 , Figure 4 , the second radiation unit 3 includes a second radiation arm 31 and a second feeding component 32. The second feeding component 32 is arranged on the reflector 1, and the second radiation arm 31 is arranged at one end of the second feeding component 32 away from the reflector 1, and the second feeding component 32 is electrically connected to the feeding network on the reflector 1.

[0057] It should be noted that on the premise of ensuring that the second radiation unit 3 operates in the second frequency band, the structural implementation forms of the second radiation arm 31 and the second feeding component 32 in the present invention are not limited.

[0058] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. An array antenna, characterized in that, Comprising: A reflector; A first radiation unit, disposed on the reflector, and a plurality of the first radiation units are provided; And, A second radiation unit, disposed on the reflector, and a plurality of the second radiation units are provided. The plurality of first radiation units and the plurality of second radiation units are distributed in an array; Wherein, the first radiation unit operates in a first frequency band, the second radiation unit operates in a second frequency band, and the lowest operating frequency of the first frequency band is higher than the highest operating frequency of the second frequency band.

2. The array antenna according to claim 1, wherein The first radiation unit includes: A first feeding component, disposed on the reflector; A coupling component, disposed on the first feeding component, the coupling component having a plurality of coupling gaps distributed at intervals, and the plurality of coupling gaps are symmetrically distributed about the central axis of the first radiation unit; and, A first radiation arm, and a plurality of the first radiation arms are provided and are respectively disposed in the plurality of coupling gaps one by one. The length of the first radiation arm extends along the length direction of the corresponding coupling gap, and each of the first radiation arms is electrically insulated.

3. The array antenna according to claim 2, wherein The coupling component includes a plurality of coupling pair arms disposed on the first feeding component, the coupling pair arms having the coupling gaps, and the plurality of coupling pair arms are symmetrically distributed about the central axis of the first radiation unit.

4. The array antenna according to claim 3, characterized in that The coupling pair arm includes two cross arms distributed at intervals and having one end connected to the first feeding component. The coupling gap is provided between the two cross arms, and the length extending direction of the cross arm is parallel to the plane where the reflector is located.

5. The array antenna according to claim 4, wherein The cross section of the cross arm opposite to the first radiation arm is a flat structure, and the coupling surface of the cross arm close to the coupling gap is perpendicular to the plane where the reflector is located.

6. The array antenna according to claim 3, wherein The coupling component further includes a plurality of conductive dielectric members, and adjacent two coupling pair arms are connected by the conductive dielectric members.

7. The array antenna according to claim 2, wherein The first feeding component includes a first support arm vertically disposed on the reflector, the coupling component is disposed at an end of the first support arm away from the reflector, and the first support arm is provided with a choke slot, and the choke slot is disposed below the coupling gap.

8. The array antenna according to claim 7, wherein The length of the first radiation arm is λ / 4, and the length of the first support arm is λ / 4; wherein, λ is the wavelength of the electromagnetic wave at the center frequency point of the first frequency band in the air.

9. The array antenna according to claim 7, characterized in that, The first radiation unit further includes a coaxial cable, the outer conductor of the coaxial cable is electrically connected to the corresponding first support arm, and the inner conductor is electrically connected to the relatively disposed first support arm.

10. The array antenna according to claim 1, characterized in that A loading sheet is disposed at an end of the first radiation unit away from the reflector.

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