A high-gain dual-polarized millimeter-wave antenna array

Abstract

The present invention relates to the field of antenna array technology, and in particular to a high-gain dual-polarized millimeter-wave antenna array, comprising a main unit, wherein the main unit is formed by a substrate and a pad cross-overlapping in a vertical direction to form five levels, wherein the main unit comprises a radiating subunit, an excitation subunit and a feeding subunit, wherein the radiating subunit comprises a microstrip radiator and an electric dipole pair, wherein two microstrip radiators in an outer layer and an inner layer are connected by a microstrip line, and the electric dipole pair is arranged between the microstrip line and the microstrip radiator. The present invention adopts a combination of a microstrip radiator and an electric dipole pair, and the radiator is arranged in a ring shape, which is different from the commonly used linear arrangement, and can bring significant improvements in beam forming, bandwidth, efficiency and anti-interference ability, and combines the microstrip antenna for beam control and gain enhancement, and the electric dipole antenna can provide the advantages of a wider radiation pattern and a higher bandwidth, and is more suitable for antenna arrays in the millimeter-wave frequency band.

Description

Technical Field

[0001] The present invention relates to the technical field of antenna arrays, and more specifically, to a high-gain dual-polarized millimeter wave antenna array. Background Art

[0002] An antenna array is an antenna system composed of multiple antenna units (commonly referred to as "antenna elements") that are arranged in a specific geometric arrangement. The antenna array can achieve beam control, directional transmission and reception of signals by rationally designing the relative position, phase and amplitude of each antenna unit.

[0003] Millimeter-wave-level antenna arrays refer to a type of antenna array system that operates in the millimeter-wave frequency band (usually between 30 GHz and 300 GHz). Since the millimeter-wave frequency band has a shorter wavelength (approximately 1 to 10 mm), it can achieve higher bandwidth, higher frequency utilization, and higher spatial resolution. However, its design and implementation also face many technical challenges and require high-precision control and integration technology.

[0004] The current millimeter wave antenna arrays mainly have two schemes: parallel feeding and series feeding:

[0005] 1. Parallel feeding scheme

[0006] This scheme mainly uses parallel power dividers to evenly distribute electromagnetic energy from the input port to each antenna unit, such as Figure 8 As shown, the structure works in the 60G millimeter wave frequency band, uses substrate integrated waveguide as the feeding network transmission line, the antenna unit is a slot-fed magnetoelectric dipole, and each unit on the antenna array is arranged in a rectangular two-dimensional plane.

[0007] 2. Series Feeding Scheme

[0008] This structure connects each radiating element in series to form an antenna array, such as Fig. 9 As shown, the substrate integrated waveguide transmission line excites each antenna unit through the slot, and the antenna units are in series. This figure shows a linear array antenna fed in series. In addition to the one-dimensional linear array, the two-dimensional planar antenna array can also be fed in series.

[0009] However, in the actual application of millimeter wave antenna arrays, there are the following defects:

[0010] When the antenna array is large, the feeding network of the parallel feeding scheme becomes very complicated, usually requiring a multi-layer structure, and the processing and manufacturing cost is very high. In addition, the parallel feeding scheme is not easy to achieve dual-polarization radiation of the antenna, while the series feeding scheme is more suitable for one-dimensional linear arrays. When designing a two-dimensional antenna array, the feeding network is also relatively complicated. When designing dual polarization, differential feeding must be used, and single-ended feeding cannot be used.

[0011] In summary, there is an urgent need for a dual-polarization radiating antenna array that can generate high gain without a complex feeding network. Summary of the invention

[0012] The purpose of the present invention is to design a high-gain dual-polarized millimeter-wave antenna array to solve the above-mentioned problem of needing to achieve high gain through a complex feeding network.

[0013] The present invention provides a high-gain dual-polarized millimeter wave antenna array, comprising a main unit, wherein the main unit is formed by a substrate and a pad being cross-stacked in a vertical direction to form five levels, and the main unit comprises a radiation subunit, an excitation subunit and a feeding subunit;

[0014] The radiating subunit arranged on the top first level includes a microstrip radiator and an electric dipole pair, wherein the four microstrip radiators are arranged in a concentric ring shape, the two microstrip radiators in the outer layer and the inner layer are connected by a microstrip line, and the electric dipole pair is arranged between the microstrip line and the microstrip radiator;

[0015] The excitation subunit arranged on the second level includes an excitation slot opened on the substrate, and the microstrip line is arranged above the center of the excitation slot to excite the microstrip radiator by coupling the energy of the excitation slot;

[0016] An annular metal wall is provided between the second and third layers, and the metal wall and the upper and lower layers are combined to form a circular resonant cavity, and a feeding gap is provided below the circular resonant cavity for coupling the polarization energy of the fourth and fifth layers;

[0017] The feeding subunit includes a vertical polarization feeding waveguide and a horizontal polarization feeding waveguide, wherein the vertical polarization feeding waveguide is arranged on the fourth level, and the horizontal polarization feeding waveguide is arranged on the fifth level.

[0018] As a further solution of the present invention: the microstrip lines are arranged radially, and after being connected with the microstrip radiator, a plurality of uniform fan-shaped areas are formed, and the electric dipole pairs are placed in the fan-shaped areas with a posture pointing to the center of the microstrip radiator.

[0019] As a further solution of the present invention: the number of electric dipole pairs in the sector-shaped region separating two outer microstrip radiators is twice that of the sector-shaped region separating two inner microstrip radiators.

[0020] As a further solution of the present invention: the excitation slots are divided into two layers, inner and outer, corresponding to the microstrip radiator; the excitation slots located in the outer layer are arranged at intervals and combined into a circular ring shape, while the excitation slots located in the inner layer are in the shape of an integrally connected circular ring.

[0021] As a further solution of the present invention: a via hole connected to the electric dipole pair of the upper layer is arranged on the edge of the excitation slot located in the inner layer.

[0022] As a further solution of the present invention: the feeding slot is cross-shaped, a coupling slot matching the feeding slot is opened at the center of the fourth level, and the feeding slot couples the energy of the vertical polarization feeding waveguide and the horizontal polarization feeding waveguide through the coupling slot.

[0023] The beneficial effects of the present invention are:

[0024] The present invention combines a microstrip radiator with an electric dipole pair, and the radiator is arranged in a ring shape, which is different from the commonly used linear arrangement. It can bring significant improvements in beam forming, bandwidth, efficiency and anti-interference ability. It combines a microstrip antenna for beam control and gain enhancement, and the electric dipole antenna can provide the advantages of a wider radiation pattern and a higher bandwidth, which is more suitable for antenna arrays in the millimeter wave frequency band.

[0025] Different from the traditional method of feeding with a series or parallel transmission line network, the present invention opens a slot on the ring resonant cavity to feed the antenna unit. Slot feeding can reduce the resonant frequency of the antenna in the frequency band, provide a wider operating frequency band than the traditional feeding network, provide a more flexible impedance matching solution, avoid the bandwidth limitation of the traditional feeding method, and by opening a slot in the resonant cavity, the feeding unit can be integrated into the antenna structure very compactly and efficiently. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of a high-gain dual-polarized millimeter-wave antenna array proposed by the present invention;

[0027] Figure 2 It is a schematic diagram of the exploded structure of a high-gain dual-polarized millimeter-wave antenna array proposed by the present invention;

[0028] Figure 3 This is a schematic diagram of a first-level top view of a high-gain dual-polarized millimeter-wave antenna array proposed by the present invention;

[0029] Figure 4 It is a schematic diagram of a second-level top view of a high-gain dual-polarized millimeter-wave antenna array proposed by the present invention;

[0030] Figure 5This is a schematic top view of the third level of a high-gain dual-polarized millimeter-wave antenna array proposed by the present invention;

[0031] Figure 6 It is a schematic top view of the fourth level of a high-gain dual-polarized millimeter-wave antenna array proposed by the present invention;

[0032] Figure 7 It is a top view schematic diagram of the fifth level of a high-gain dual-polarized millimeter-wave antenna array proposed by the present invention;

[0033] Figure 8 is a schematic diagram of an antenna array of an existing parallel feeding scheme;

[0034] Fig. 9 It is a schematic diagram of the antenna array of the existing series feeding scheme.

[0035] In the figure: 1, substrate; 2, pad; 110, microstrip radiator; 120, electric dipole pair; 130, microstrip line; 210, excitation slot; 220, via; 230, metal wall; 310, feeding slot; 410, coupling slot; 420, vertical polarization feeding waveguide; 510, horizontal polarization feeding waveguide. DETAILED DESCRIPTION

[0036] The subject matter described herein will now be discussed with reference to example implementations. It should be understood that the discussion of these implementations is only to enable those skilled in the art to better understand and implement the subject matter described herein, and the functions and arrangements of the elements discussed may be changed without departing from the scope of protection of the contents of this specification. Various examples may omit, replace, or add various processes or components as needed. In addition, the features described in some examples may also be combined in other examples.

[0037] At least one embodiment of the present invention discloses a high-gain dual-polarized millimeter wave antenna array, such as Figure 1 - Figure 7 As shown, it includes a total unit, wherein the total unit is formed by a substrate 1 and a pad 2 cross-stacked in the vertical direction to form five levels, and the total unit includes a radiation subunit, an excitation subunit and a feeding subunit;

[0038] The radiation subunit arranged on the top first level includes a microstrip radiator 110 and an electric dipole pair 120. The four microstrip radiators 110 are arranged in a concentric ring shape. The two microstrip radiators 110 in the outer layer and the inner layer are connected by a microstrip line 130. The electric dipole pair 120 is arranged between the microstrip line 130 and the microstrip radiator 110.

[0039] The excitation subunit disposed on the second level includes an excitation slot 210 opened on the substrate 1, and the microstrip line 130 is disposed above the center of the excitation slot 210 to excite the microstrip radiator 110 by coupling the energy of the excitation slot 210;

[0040] An annular metal wall 230 is provided between the second and third layers, and the metal wall 230 and the upper and lower layers are combined to form a circular resonant cavity, and a feeding slot 310 is provided below the circular resonant cavity for coupling the polarization energy of the fourth and fifth layers;

[0041] The feeding subunit includes a vertical polarization feeding waveguide 420 and a horizontal polarization feeding waveguide 510 . The vertical polarization feeding waveguide 420 is disposed on the fourth level, and the horizontal polarization feeding waveguide 510 is disposed on the fifth level.

[0042] like Figure 4 As shown, the radiation subunits of the present invention are arranged in a ring, which is different from the linear arrangement of most arrays. The electric dipoles are excited by the gaps in the lower layer, such as Figure 4 As shown, the connecting microstrip line 130 is disposed above the center of the slot and excites the annular microstrip radiator 110 by coupling the energy of the slot 410 .

[0043] Two radiators (microstrip radiator 110 and electric dipole pair 120) are combined, and the radiators are arranged in a ring shape, which is different from the commonly used linear arrangement. The advantages of this arrangement are:

[0044] 1. Optimize beamforming: The combination of microstrip antenna and electric dipole antenna can provide different radiation characteristics in different directions. Microstrip antenna is usually used for beam control and gain enhancement, while electric dipole antenna can provide a wider radiation pattern and higher bandwidth. The combination of the two can more flexibly adjust the beam direction and shape to meet the needs of various applications.

[0045] 2. Improve bandwidth and efficiency: Electric dipole antennas can provide relatively uniform radiation performance in a larger frequency band due to their wide bandwidth. Microstrip antennas can provide higher gain and better directivity on this basis. By combining the two, a wider working bandwidth and higher efficiency can be achieved.

[0046] 3. Improving anti-interference capability: When the microstrip radiator 110 is combined with the electric dipole antenna, the radiation pattern in the array can be more flexible and can effectively suppress interference, especially in the high-frequency millimeter wave band. They can help the system enhance signal quality and reduce noise.

[0047] The microstrip lines 130 are arranged radially, and after being connected with the microstrip radiator 110 , a plurality of uniform fan-shaped regions are formed. The electric dipole pairs 120 are placed in the fan-shaped regions in a posture pointing to the center of the microstrip radiator 110 .

[0048] The number of electric dipole pairs 120 in the sector-shaped region separated by the two outer microstrip radiators 110 is twice that of the sector-shaped region separated by the two inner microstrip radiators 110 .

[0049] By designing the microstrip radiator 110 and the electric dipole pair 120 to be separated from each other, the mutual coupling problem between the two can be effectively solved, thereby avoiding signal interference and efficiency loss.

[0050] The excitation slots 210 are divided into two layers, inner and outer, corresponding to the microstrip radiator 110. The excitation slots 210 in the outer layer are arranged at intervals and combined into a circular ring shape, while the excitation slots 210 in the inner layer are in a circular ring shape that is connected as a whole.

[0051] A via hole 220 connected to the electric dipole pair 120 of the upper layer is arranged on the edge of the excitation slot 210 located in the inner layer.

[0052] The feeding slot 310 is in a cross shape, and a coupling slot 410 matching the feeding slot 310 is provided at the center of the fourth level. The feeding slot 310 couples the energy of the vertical polarization feeding waveguide 420 and the horizontal polarization feeding waveguide 510 via the coupling slot 410 .

[0053] Different from the traditional method of feeding with a series or parallel transmission line network, the present invention feeds the antenna unit by opening a slot on the annular resonant cavity. Slot feeding can reduce the resonant frequency of the antenna in the frequency band and provide a wider working frequency band than the traditional feeding network, because the slot can provide a more flexible impedance matching solution, avoiding the bandwidth limitation in the traditional feeding method, and by opening a slot in the resonant cavity, the feeding unit can be very compactly and efficiently integrated in the antenna structure. Especially in microwave and millimeter wave antenna arrays, the slot method can achieve better performance without increasing the extra size. Since the feeding is directly performed in the cavity, this method can usually reduce the additional feeding network structure and wiring. In addition, using the slot of the resonant cavity for feeding can reduce the loss of electromagnetic waves in the antenna structure. Since the feeding directly acts on the radiation surface of the antenna, the attenuation and reflection of the signal can be minimized, and a higher feeding efficiency can usually be obtained. Feeding is performed directly in the resonant cavity, which helps to reduce external interference and coupling problems.

[0054] The above describes an embodiment of the present invention, but this embodiment is not limited to the above-mentioned specific implementation mode. The above-mentioned specific implementation mode is merely illustrative and not restrictive. Under the guidance of this embodiment, ordinary technicians in this field can also make more forms of equivalent embodiments, all of which are within the protection of this embodiment.

Claims

1. A high-gain dual-polarized millimeter-wave antenna array, characterized in that: It comprises a main unit, wherein the main unit is formed by a substrate (1) and a pad (2) being cross-stacked in a vertical direction to form five layers, and the main unit comprises a radiation subunit, an excitation subunit and a feed subunit; The radiation subunit arranged on the top first level comprises a microstrip radiator (110) and an electric dipole pair (120), the four microstrip radiators (110) are arranged in a concentric ring shape, the two microstrip radiators (110) in the outer layer and the inner layer are connected by a microstrip line (130), and the electric dipole pair (120) is arranged between the microstrip line (130) and the microstrip radiator (110); The excitation subunit arranged on the second level comprises an excitation slot (210) opened on the substrate (1), and the microstrip line (130) is arranged above the center of the excitation slot (210) to excite the microstrip radiator (110) by coupling the energy of the excitation slot (210); An annular metal wall (230) is provided between the second layer and the third layer, the metal wall (230) and the upper and lower layers enclose a circular resonant cavity, and a feeding gap (310) is provided below the circular resonant cavity for coupling polarization energy of the fourth and fifth layers; The feeding subunit comprises a vertical polarization feeding waveguide (420) and a horizontal polarization feeding waveguide (510), wherein the vertical polarization feeding waveguide (420) is arranged on the fourth level, and the horizontal polarization feeding waveguide (510) is arranged on the fifth level.

2. A high-gain dual-polarized millimeter-wave antenna array according to claim 1, characterized in that: The microstrip lines (130) are arranged radially, and after being connected to the microstrip radiator (110), a plurality of uniform fan-shaped areas are formed, and the electric dipole pairs (120) are placed in the fan-shaped areas in a posture pointing to the center of the microstrip radiator (110).

3. A high-gain dual-polarized millimeter wave antenna array according to claim 2, characterized in that: The number of electric dipole pairs (120) in the sector-shaped region separated by two outer microstrip radiators (110) is twice that of the number of electric dipole pairs (120) in the sector-shaped region separated by two inner microstrip radiators (110).

4. The high-gain dual-polarized millimeter wave antenna array according to claim 3, characterized in that: The excitation slots (210) and the microstrip radiator (110) are divided into two layers, an inner layer and an outer layer, respectively; the excitation slots (210) located in the outer layer are arranged at intervals and combined into a circular ring shape; and the excitation slots (210) located in the inner layer are in the shape of an integrally connected circular ring.

5. The high-gain dual-polarized millimeter wave antenna array according to claim 4, characterized in that: A via hole (220) connected to the electric dipole pair (120) of the upper layer is provided on the edge of the excitation slot (210) located in the inner layer.

6. A high-gain dual-polarized millimeter wave antenna array according to claim 5, characterized in that: The feeding slot (310) is in a cross shape, and a coupling slot (410) matching the feeding slot (310) is provided at the center of the fourth level, and the feeding slot (310) couples the energy of the vertical polarization feeding waveguide (420) and the horizontal polarization feeding waveguide (510) via the coupling slot (410).

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