Low-frequency radiation unit and array antenna

Abstract

Provided in the present application are a low-frequency radiation unit and an array antenna. The low-frequency radiation unit comprises: a feed base, which comprises two orthogonally distributed baluns; and a low-frequency radiation element, which comprises a substrate and four first radiators which are distributed on the substrate in a centrosymmetric manner, wherein the four first radiators are orthogonally distributed in respect of polarization, the first radiators each comprise annular radiation arms and split-ring resonators, which are distributed on different dielectric layers of the substrate, each of the annular radiation arms corresponds to a plurality of split-ring resonators, the annular radiation arms are distributed in a centrosymmetric manner, each of the split-ring resonators is configured in a half-surrounded manner and has a split, and an orthographic projection of each split-ring resonator is located on the corresponding annular radiation arm. The low-frequency radiation unit and array antenna provided in the present application aim to solve the problem of there being interference between antennas in different frequency bands in conventional techniques.

Description

Low-frequency radiating unit and array antenna

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application No. 2023107593990, filed on June 26, 2023, entitled “LOW FREQUENCY RADIATION UNIT AND ARRAY ANTENNA,” which is incorporated herein by reference in its entirety. Technical Field

[0003] The present application relates to the technical field of base station antennas, and in particular to a low-frequency radiation unit and an array antenna. Background Art

[0004] With the widespread adoption of wireless communication applications and increasing consumer demand, wireless communication systems must meet requirements such as lower latency, greater transmission throughput, and greater stability. Expanding spectrum resources is a key means of increasing channel capacity. Wireless communication has evolved from low-frequency 600MHz, 700MHz, and 900MHz to today's high-frequency 3.5GHz and 4.9GHz. In the field of base station antennas, frequency bands continue to expand, but base station sites are limited, making it impossible to deploy antennas in sufficient frequency bands within existing resources. Therefore, within the limited antenna aperture, the industry typically utilizes multiple frequency bands placed on the same antenna surface to conserve resources. In this scenario, resolving mutual interference between antennas in different frequency bands and achieving ultra-wideband antennas present technical challenges.

[0005] To address inter-band interference, common methods used in the industry to reduce low-frequency interference on mid- and high-frequency bands include using high-resistance lines, adding filtering branches, or adding inductors. However, these structures often narrow the impedance bandwidth of the low-frequency radiator itself, making it difficult to achieve a low-frequency radiator with a wide impedance bandwidth that transmits high-frequency radiation waves.

[0006] Summary of the Invention

[0007] The present application provides a low-frequency radiation unit and an array antenna, aiming to solve the problem of interference between antennas of different frequency bands in traditional technologies.

[0008] In order to solve the above problems, the present application provides a low-frequency radiation unit, comprising:

[0009] A feed base including two baluns arranged in orthogonal relation; and

[0010] A low-frequency radiating element includes a substrate and four first radiators centrally and symmetrically distributed on the substrate, wherein the four first radiators are orthogonally polarized;

[0011] Each of the first radiators includes a ring-shaped radiation arm and a split resonant ring, the ring-shaped radiation arm and the split resonant ring are distributed on different dielectric layers of the substrate, and each of the ring-shaped radiation arms corresponds to a plurality of split resonant rings;

[0012] The annular radiation arms are distributed in a centrally symmetrical manner, and the open resonant rings are arranged in a semi-enclosed manner and have an opening. The orthographic projection of each open resonant ring is located on the corresponding annular radiation arm.

[0013] According to a low-frequency radiation unit provided by the present application, the annular radiation arm has a plurality of radiation branches, and the opening directions of two adjacent open resonant rings on each radiation branch arm differ by 180°.

[0014] According to a low-frequency radiation unit provided by the present application, the center of the orthographic projection of each split resonant ring is located on the corresponding radiation branch arm.

[0015] According to a low-frequency radiation unit provided by the present application, the distances between every two adjacent open resonant rings are equal.

[0016] According to a low-frequency radiation unit provided by the present application, the open resonant ring includes a circular ring open type, a square ring open type or a hexagonal open type.

[0017] According to a low-frequency radiation unit provided in the present application, the low-frequency radiation unit also includes four second radiators arranged at the center of the substrate, the four second radiators are located between the first radiators and are distributed in a centrally symmetrical manner, and the balun is electrically connected to the second radiators respectively.

[0018] According to a low-frequency radiation unit provided by the present application, the second radiator is L-shaped.

[0019] According to a low-frequency radiation unit provided by the present application, the low-frequency radiation unit further includes four third radiators provided on the substrate, each of the third radiators is located between two adjacent first radiators and is centrally symmetrically distributed.

[0020] According to a low-frequency radiation unit provided by the present application, the third radiator is linear.

[0021] The present application also provides an array antenna, comprising:

[0022] A low-frequency radiation unit, wherein the low-frequency radiation unit is the low-frequency radiation unit as described in any one of the above items; and a high-frequency radiation unit;

[0023] Among them, each of the low-frequency radiation units corresponds to four of the high-frequency radiation units, each of the first radiators of each of the low-frequency radiation units corresponds to one of the high-frequency radiation units, the orthographic projection of each of the first radiators is located on the corresponding high-frequency radiation unit, and the circumference of the open resonant ring is 0.25 to 0.35λ of the corresponding high-frequency radiation unit.

[0024] The low-frequency radiation unit provided in the present application is provided with a first radiator, and an open resonant ring structure is added without affecting the characteristics of the low-frequency radiation unit itself, which can produce a wave-transmitting effect on high-frequency signals, reduce the interference between low-frequency signals and high-frequency signals, and improve the working effect of the antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the present application or the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0026] FIG1 is a schematic structural diagram of a low-frequency radiation unit provided by the present application;

[0027] FIG2 is a schematic diagram of the top view structure of FIG1;

[0028] FIG3 is a schematic structural diagram of a first embodiment of the split resonant ring in FIG1 ;

[0029] FIG4 is a schematic structural diagram of a second embodiment of the split resonant ring in FIG1 ;

[0030] FIG5 is a schematic structural diagram of a third embodiment of the split ring resonant circuit in FIG1 ;

[0031] FIG6 is a schematic diagram of the structure of the array antenna provided in this application;

[0032] Figure numerals: 10: array antenna; 100: low-frequency radiation unit; 110: feeding base; 120: balun; 130: low-frequency radiation element; 131: substrate; 132: first radiator; 133: second radiator; 134: third radiator; 135: annular radiation arm; 136: open resonant ring; 137: radiation branch arm; 200: high-frequency radiation unit. DETAILED DESCRIPTION

[0033] To make the objectives, technical solutions, and advantages of this application more clear, the technical solutions of this application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.

[0034] In the description of the embodiments of the present application, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application 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 operate in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0035] In the description of the embodiments of this application, it should be noted that, unless otherwise specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of this application based on the specific circumstances.

[0036] In the embodiments of the present application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0037] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0038] The low-frequency radiation unit 100 and the array antenna 10 of the present application are described below with reference to FIG. 1 to FIG. 6 .

[0039] In conventional technology, signal interference can occur between radiating units in different frequency bands. In view of this, referring to Figures 1-2 , the present application provides a low-frequency radiating unit 100 comprising a feed base 110 and a low-frequency radiating element 130. The feed base 110 includes two orthogonally arranged baluns 120. The low-frequency radiating element 130 comprises a substrate 131 and four first radiators 132 centrally and symmetrically distributed on the substrate 131. The four first radiators 132 are orthogonally polarized. It should be noted that the four first radiators 132 constitute two orthogonally arranged oscillators, and the orthogonally distributed baluns 120 feed the two oscillators to achieve ±45° dual-polarization characteristics. Specifically, the baluns 120 can be connected to the substrate 131 by opening a hole for insertion, and then the actual electrical connection is made by soldering.

[0040] Each first radiator 132 includes a ring-shaped radiating arm 135 and a split resonant ring 136. The ring-shaped radiating arm 135 and the split resonant ring 136 are distributed in different dielectric layers of the substrate 131, are physically separated, and are electrically coupled. Each ring-shaped radiating arm 135 corresponds to a plurality of split resonant rings 136. The ring-shaped radiating arms 135 are centrally symmetrically distributed, and the split resonant rings 136 are semi-enclosed and have openings. The orthographic projection of the split resonant ring 136 is located on the corresponding ring-shaped radiating arm 135. It is understood that when the low-frequency radiating unit 100 and the high-frequency radiating unit 200 are used in conjunction, the split resonant ring 136 can produce a wave-transmitting effect on the high-frequency oscillator based on the resonance excited by the ring-shaped radiating arm 135. Similar to the working principle of a split resonant ring metasurface, when the circumference of the split resonant ring is 0.25 to 0.35λ of the corresponding high-frequency oscillator, the split resonant ring 136 can excite a resonance, thereby producing a wave-transmitting effect within the range of the resonance point.

[0041] The low-frequency radiation unit 100 provided in the present application is provided with a first radiator 132. An open resonant ring 136 structure is added without affecting the characteristics of the low-frequency radiation unit 100 itself, which can produce a wave-transmitting effect on high-frequency signals, reduce the interference between low-frequency signals and high-frequency signals, and improve the working effect of the antenna.

[0042] Specifically, in order to ensure the wave transmission effect, the annular radiation arm 135 has multiple radiation branches 137, and the opening directions of the two adjacent open resonant rings 136 on each radiation branch arm 137 differ by 180°. Furthermore, the center of the positive projection of the open resonant ring 136 is located on the corresponding radiation branch arm 137, and the spacing between each two adjacent open resonant rings 136 is equal.

[0043] It should be noted that, referring to Figures 3 to 5, the open resonant ring 136 includes a circular open type, a square open type or a hexagonal open type. Correspondingly, the annular radiation arm 135 can also be set as a square radiation arm, a circular ring radiation arm, a hexagonal radiation arm, etc.

[0044] To increase the bandwidth of the low-frequency radiating unit 100, in addition to the aforementioned first radiator 132, the low-frequency radiating unit 130 further includes four second radiators 133 disposed at the center of the substrate 131. The four second radiators 133 are located between the first radiators 132 and are centrally symmetrically distributed. The balun 120 is electrically connected to each second radiator 133. It should be noted that when the second radiator 133 is not provided, the balun 120 can be electrically connected to the annular radiating arm 135. When the second radiator 133 is provided, the balun 120 is electrically connected to the second radiator 133. For ease of arrangement, in an optional embodiment, the second radiator 133 is L-shaped. Of course, the second radiator 133 can also be configured as a line or other shape.

[0045] Furthermore, the low-frequency radiation element 130 also includes four third radiators 134 provided on the substrate 131. Each third radiator 134 is located between two adjacent first radiators 132 and is centrally symmetrically distributed. In an optional embodiment, the third radiator 134 is linear. Of course, the third radiator 134 can also be set to a T-shape or other shapes. It should be noted that the second radiator 133 or the third radiator 134 can be selectively set on the basis of the first radiator 132, or the second radiator 133 or the third radiator 134 can be set at the same time. This is not limited in this application. In this embodiment, by simultaneously providing the first radiator 132, the second radiator 133 and the third radiator 134, the three radiators constitute the radiation surface of the radiation unit, which mainly realizes the radiation of electromagnetic waves. Among them, the three radiators are all centrally symmetrical about the center point of the substrate 131, the second radiator 133 is directly electrically connected to the balun 120, the second radiator 133 and the third radiator 134 are coupled to each other, and the first radiator 132 and the second radiator 133 are coupled to each other through a gap. The three radiators respectively excite a resonance point, which expands the frequency band of the radiation unit and realizes ultra-wideband characteristics.

[0046] Based on the above-mentioned low-frequency radiating unit 100, referring to FIG6 , the present application further provides an array antenna 10 comprising: a low-frequency radiating unit 100 and a high-frequency radiating unit 200; wherein each low-frequency radiating unit 100 corresponds to four high-frequency radiating units 200, and the high-frequency radiating units 200 are arranged below the low-frequency radiating unit 100 with a certain spacing in the horizontal and vertical directions, forming a 2×2 high-frequency array. The first radiator 132 of each low-frequency radiating unit 100 corresponds to a high-frequency radiating unit 200, and the orthographic projection of each first radiator 132 is located on the corresponding high-frequency radiating unit 200. The circumference of the open resonant ring 136 is 0.25 to 0.35λ of the corresponding high-frequency radiating unit 200.

[0047] It is understandable that the low-frequency radiating element 100 is positioned directly above the aperture of the high-frequency radiating element 200, partially obscuring the high-frequency radiating element 200. The secondary radiation of the induced current excited by the low-frequency radiating element 100 can affect the high-frequency radiation characteristics. The split ring resonator 136 utilizes the properties of metamaterials, which are transparent to high-frequency signals and reduce the impact of the low-frequency radiating element 100 on the high-frequency radiation characteristics.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A low-frequency radiation unit, comprising: A feeding base including two baluns arranged orthogonally; as well as The low-frequency radiation element comprises a substrate and four first radiation bodies centrally and symmetrically distributed on the substrate, wherein the four first radiation bodies are orthogonally polarized. Each of the first radiators includes a ring-shaped radiation arm and an open resonant ring, the ring-shaped radiation arm and the open resonant ring are distributed in different dielectric layers of the substrate, and each of the ring-shaped radiation arms corresponds to a plurality of the open resonant rings; The annular radiation arms are distributed in a centrally symmetrical manner, and the open resonant rings are arranged in a semi-enclosed manner and have an opening. The orthographic projection of each open resonant ring is located on the corresponding annular radiation arm.

2. The low-frequency radiation unit according to claim 1, wherein: The annular radiation arm has a plurality of radiation branch arms, and the opening directions of two adjacent open resonant rings on each radiation branch arm differ by 180°.

3. The low-frequency radiation unit according to claim 2, wherein: The center of the orthographic projection of each split resonant ring is located on the corresponding radiation branch arm.

4. The low-frequency radiation unit according to claim 1, wherein: The distances between any two adjacent split resonant rings are equal.

5. The low-frequency radiation unit according to claim 1, wherein: The open resonant ring includes a circular open type, a square open type or a hexagonal open type.

6. The low-frequency radiation unit according to claim 1, wherein: The low-frequency radiation element further includes four second radiation bodies arranged at the center of the substrate, the four second radiation bodies are located between the first radiation bodies and are centrally symmetrically distributed, and the balun is electrically connected to the second radiation bodies respectively.

7. The low-frequency radiation unit according to claim 6, wherein: The second radiator is L-shaped.

8. The low-frequency radiation unit according to claim 1, wherein: The low-frequency radiation element further includes four third radiation bodies arranged on the substrate, each of the third radiation bodies is located between two adjacent first radiation bodies and is centrally symmetrically distributed.

9. The low-frequency radiation unit according to claim 8, wherein: The third radiator is linear.

10. An array antenna, comprising: A low-frequency radiation unit, wherein the low-frequency radiation unit is the low-frequency radiation unit according to any one of claims 1 to 9; and a high-frequency radiation unit, in, Each of the low-frequency radiation units corresponds to four of the high-frequency radiation units, each of the first radiators of each of the low-frequency radiation units corresponds to one of the high-frequency radiation units, the orthographic projection of each of the first radiators is located on the corresponding high-frequency radiation unit, and the circumference of the open resonant ring is 0.25 to 0.35λ of the corresponding high-frequency radiation unit.

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