Millimeter wave broadband circularly polarized antenna array and manufacturing method thereof

Abstract

The invention belongs to the field of antennas, and discloses a millimeter wave broadband circularly polarized antenna array and a manufacturing method thereof. The fourth metal layer is used for receiving and transmitting electromagnetic waves based on the sequential rotation feed network; the fourth metal layer is also used for serving as a ground plane of the grounding coplanar waveguide; the third dielectric layer is used for transmitting the received electromagnetic waves to the third metal layer; metal via holes are introduced into the third dielectric layer to realize the performance of the grounding coplanar waveguide; the third metal layer is used for coupling electromagnetic waves to the first radiation layer and the second radiation layer based on slot coupling; the third metal layer is also used for serving as a ground plane of the grounded coplanar waveguide; the first radiation layer and the second radiation layer are respectively used for directionally radiating electromagnetic waves to a free space; metal via holes are introduced into the first radiation layer and the second radiation layer, so that the performance of the magnetoelectric dipole antenna is realized; the millimeter wave antenna meets the requirement of a millimeter wave mobile communication working frequency band, and has the characteristics of large axial ratio bandwidth, easiness in processing, low loss and stable directional diagram.

Description

Technical Field

[0001] The present invention belongs to the technical field of antennas, and in particular relates to a millimeter wave broadband circularly polarized antenna array and a manufacturing method thereof. Background Art

[0002] With the rapid development of 5G mobile communication technology, the millimeter wave frequency band has been widely studied and applied due to its rich spectrum resources and high transmission rate. Antennas, as key components within wireless communication systems, play an important role in transmitting or receiving electromagnetic energy. Therefore, it is very important to develop broadband millimeter wave antennas to adapt to the rapid development of 5G mobile communication systems.

[0003] Faced with the increasingly complex communication environment, linearly polarized antennas are difficult to combat multipath effects, and their shortcomings of being prone to polarization deflection are gradually exposed; circularly polarized antennas have the characteristics of suppressing multipath effects, resisting antenna attenuation in rain and fog, having low polarization losses, and resisting the Faraday effect of the ionosphere. They have strong advantages in the face of complex electromagnetic application environments and are very suitable for 5G millimeter wave and satellite communication systems; however, most of the existing millimeter wave circularly polarized antenna arrays can only cover a single frequency band, so it is very necessary to develop wide-band antennas. Summary of the invention

[0004] In view of the technical problems existing in the prior art, the present invention provides a millimeter-wave broadband circularly polarized antenna array and a manufacturing method thereof, so as to solve the technical problem that most of the existing millimeter-wave circularly polarized antenna arrays can only cover a single frequency band.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: The present invention provides a millimeter wave broadband circularly polarized antenna array, comprising a first radiation layer, a second radiation layer, a third metal layer, a third dielectric layer and a fourth metal layer which are stacked in sequence; The fourth metal layer is used to receive and transmit electromagnetic waves to the third dielectric layer based on a sequential rotation feeding network; wherein the fourth metal layer is also used to serve as a ground plane of a grounded coplanar waveguide; The third dielectric layer is used to transmit the received electromagnetic wave to the third metal layer; wherein the performance of the grounded coplanar waveguide is achieved by introducing metal vias in the third dielectric layer; The third metal layer is used to couple the received electromagnetic waves to the first radiation layer and the second radiation layer based on slot coupling; wherein the third metal layer is also used to serve as a ground plane of the grounded coplanar waveguide; The first radiation layer and the second radiation layer are respectively used to directionally radiate the received electromagnetic waves to the free space; wherein, the performance of the magneto-electric dipole antenna is achieved by introducing metal vias into the first radiation layer and the second radiation layer.

[0006] Furthermore, the first radiation layer includes a first metal layer and a first dielectric layer, and the first metal layer is arranged on a first surface of the first dielectric layer; The first metal layer includes four groups of first patch units, which are distributed in a rectangular array; each group of the first patch units includes four first rectangular metal patches arranged in two rows and two columns; wherein the structures of two diagonally arranged first rectangular metal patches are the same, and the structures of two adjacent first rectangular metal patches are different; Four groups of first metal via units are arranged on the first dielectric layer, and the four groups of first metal via units are symmetrical about the center of the first dielectric layer; each group of first metal via units includes two first metal vias that are symmetrical about the center of the first patch unit; wherein the first end of the first metal via is connected to the first rectangular metal patch, and the second end of the first metal via is connected to the second radiation layer.

[0007] Further, the second radiation layer includes a second metal layer and a second dielectric layer, and the second metal layer is arranged on a first surface of the second dielectric layer; The second metal layer includes four groups of second patch units, which are arranged in two rows and two columns; each group of the second patch units includes two quarter-elliptical metal patches; wherein the two quarter-elliptical metal patches are symmetrical about the center of the second patch unit, and the center parts of the two quarter-elliptical metal patches are cut by the rotated ellipse; Four groups of second metal via units are arranged on the second dielectric layer, and the four groups of second metal via units are symmetrical about the center of the second dielectric layer; each group of second metal via units includes two second metal vias symmetrical about the center of the second patch unit and two third metal vias symmetrical about the center of the second patch unit.

[0008] Furthermore, the third metal layer includes a metal layer body and a first ground plane; the metal layer body and the first ground plane are both arranged on the first surface of the third dielectric layer, the center of the metal layer body coincides with the centers of the first radiation layer and the second radiation layer, and the first ground plane is arranged at the end of the metal layer body; wherein the metal layer body is provided with four rectangular gaps which are arranged in rotation sequence along the center of the metal layer body.

[0009] Furthermore, the fourth metal layer includes a one-to-four microstrip feeding network and a second ground plane; the one-to-four microstrip feeding network and the second ground plane are both arranged on the second surface of the third dielectric layer, and the center of the one-to-four microstrip feeding network coincides with the center of the first radiation layer and the second radiation layer; wherein the one-to-four microstrip feeding network is provided with four output ports, and the output electromagnetic waves of the four output ports differ in phase by 90°.

[0010] Furthermore, a fourth metal via is provided on the third dielectric layer, and the fourth metal via is symmetrically arranged about the central axis of the first ground plane; wherein one end of the fourth metal via is connected to the first ground plane, and the other end of the fourth metal via is connected to the second ground plane.

[0011] Furthermore, the first ground plane, the fourth metal via and the second ground plane form a grounded coplanar waveguide.

[0012] Furthermore, the third metal layer, the third dielectric layer and the fourth metal layer are all provided with joint mounting through holes, and the joint mounting through holes are used for mounting solder-free joints.

[0013] Furthermore, it also includes a first adhesive layer and a second adhesive layer; the first adhesive layer is used to bond the first dielectric layer and the second metal layer together; the second adhesive layer is used to bond the second radiation layer and the third metal layer together.

[0014] The present invention also provides a method for manufacturing a millimeter-wave broadband circularly polarized antenna array, comprising: According to the design requirements of the antenna, the PCB manufacturing process is adopted to obtain the dielectric substrate; Based on the grounded coplanar waveguide and magneto-electric dipole technology, a metal layer structure is realized by tinning on the surface of a dielectric substrate to obtain the millimeter-wave broadband circularly polarized antenna array.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The millimeter-wave broadband circularly polarized antenna array provided by the present invention can effectively combine the magneto-electric dipole antenna and the grounded coplanar waveguide technology to jointly realize the millimeter-wave broadband circularly polarized performance of the antenna and meet the requirements of the millimeter-wave mobile communication working frequency band; it has the characteristics of large axial ratio bandwidth, easy processing, low loss and stable radiation pattern, and also has the advantages of high processing precision. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1A schematic diagram of the three-dimensional layered structure of the millimeter-wave broadband circularly polarized antenna array provided by the present invention; Figure 2 A top view of the millimeter wave broadband circularly polarized antenna array of the present invention; Figure 3 A bottom view of the millimeter wave broadband circularly polarized antenna array of the present invention; Figure 4 It is a side view of the millimeter wave broadband circularly polarized antenna array of the present invention; Figure 5 is a schematic structural diagram of the third metal layer in the present invention; Figure 6 is a schematic structural diagram of the first radiation layer in the present invention; Figure 7 is a schematic structural diagram of the second radiation layer in the present invention; Figure 8 is a schematic diagram of the combined structure of the third metal layer and the fourth metal layer in the present invention; Fig. 9 is a schematic structural diagram of the fourth metal layer in the present invention; Fig.10 It is a curve diagram of the return loss and axial ratio of the millimeter wave broadband circularly polarized antenna array in the present invention as a function of frequency; Fig.11 is a curve diagram showing the gain of the millimeter wave broadband circularly polarized antenna array according to the present invention as a function of frequency; Fig.12 The radiation patterns of the millimeter-wave broadband circularly polarized antenna array at 26 GHz, φ=0° and φ=90° in the present invention; Fig.13 The radiation patterns of the millimeter-wave broadband circularly polarized antenna array at 28 GHz, φ=0° and φ=90° in the present invention; Fig.14 The radiation patterns of the millimeter-wave broadband circularly polarized antenna array at 30 GHz, φ=0° and φ=90° in the present invention; Fig.15 The radiation patterns of the millimeter-wave broadband circularly polarized antenna array at 32 GHz, φ=0° and φ=90° in the present invention; Fig.16 The radiation patterns of the millimeter-wave broadband circularly polarized antenna array at 34 GHz, φ=0° and φ=90° in the present invention; Fig.17 The radiation patterns of the millimeter-wave broadband circularly polarized antenna array at 36 GHz, φ=0° and φ=90° in the present invention; Fig.18 is the radiation pattern of the millimeter wave broadband circularly polarized antenna array at 38 GHz, φ=0° and φ=90° in the present invention; Fig.19 The radiation patterns of the millimeter-wave broadband circularly polarized antenna array at 40 GHz, φ=0° and φ=90° in the present invention.

[0017] Among them, 1 is the first metal layer, 2 is the first dielectric layer, 3 is the first adhesive layer, 4 is the second metal layer, 5 is the second dielectric layer, 6 is the second adhesive layer, 7 is the third metal layer, 8 is the third dielectric layer, 9 is the fourth metal layer; 21 is the first metal via; 51 is the second metal via, 52 is the third metal via; 71 is the rectangular gap, 72 is the first ground plane; 81 is the fourth metal via; 91 is the one-to-four microstrip feeding network, 92 is the second ground plane. DETAILED DESCRIPTION

[0018] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail in the following specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0019] As attached Figure 1-9 As shown, the present invention provides a millimeter wave broadband circularly polarized antenna array, including a first radiation layer, a first adhesive layer 3, a second radiation layer, a second adhesive layer 6, a third metal layer 7, a third dielectric layer 8 and a fourth metal layer 9 stacked in sequence.

[0020] The first radiation layer and the second radiation layer are respectively used to directionally radiate the received electromagnetic waves to the free space; wherein, the first radiation layer and the second radiation layer realize the performance of the magneto-electric dipole antenna by introducing metal vias; the first bonding layer 3 is used to bond the first radiation layer and the second radiation layer together, and the second bonding layer 6 is used to bond the second radiation layer and the third metal layer 7 together; the third metal layer 7 is used to couple the received electromagnetic waves to the first radiation layer and the second radiation layer based on slot coupling; wherein, the third metal layer 7 is also used to serve as the ground plane of the grounded coplanar waveguide; the third dielectric layer 8 is used to transmit the received electromagnetic waves to the third metal layer 7; wherein, the performance of the grounded coplanar waveguide is realized by introducing metal vias in the third dielectric layer 8; the fourth metal layer 9 is used to receive and transmit electromagnetic waves to the third dielectric layer 8 based on a sequential rotation feeding network; wherein, the fourth metal layer 9 is also used to serve as the ground plane of the grounded coplanar waveguide.

[0021] In the present invention, by combining the magnetoelectric dipole antenna and the grounded coplanar waveguide technology, rectangular slots that rotate sequentially along the center of the antenna and a feeding network for sequential rotation feeding are designed on the feeding structure, and two groups of rotationally symmetric electric dipoles and a group of rotationally symmetric parasitic patches are designed on the radiation structure, which together with the coupling slots that act as magnetic dipoles realize the millimeter-wave broadband circular polarization performance of the antenna and meet the requirements of the millimeter-wave mobile communication working frequency band.

[0022] As attached Figure 1-4 As shown in , the first radiation layer includes a first metal layer 1 and a first dielectric layer 2, and the first metal layer 1 is arranged on the first surface of the first dielectric layer 2; wherein the first metal layer 1 is used to combine with the first dielectric layer 2 to form a first radiation layer of the antenna array, so as to radiate the electromagnetic waves in the dielectric substrate to form electromagnetic waves in the free space; similarly, the first dielectric layer 2 is used to combine with the first metal layer 1 to form the first radiation layer of the antenna array, so as to convert the electromagnetic waves transmitted in the dielectric substrate of the lower layer into electromagnetic waves of the required frequency to form a directional beam.

[0023] The first metal layer 1 includes four groups of first patch units, which are distributed in a rectangular array and are symmetrical about the center of the first dielectric layer 2; each group of the first patch units includes four first rectangular metal patches arranged in two rows and two columns; wherein, the structures of the two diagonally arranged first rectangular metal patches are the same, and the structures of the two adjacent first rectangular metal patches are different, that is, the four first rectangular metal patches arranged in two rows and two columns are rotationally symmetrical about the center of the first patch unit; preferably, in each group of the first patch units, the size of the two first rectangular metal patches close to the center of the first dielectric layer 2 and the corner of the first dielectric layer 2 is larger than the size of the two first rectangular metal patches close to the center of the side of the first dielectric layer 2, that is, the two first rectangular metal patches close to the center of the first dielectric layer 2 and the corner of the first dielectric layer 2 use larger rectangular metal patches, and the two first rectangular metal patches close to the center of the side of the first dielectric layer 2 use smaller rectangular metal patches.

[0024] Four groups of first metal via units are arranged on the first dielectric layer 2, and the four groups of first metal via units are symmetrical about the center of the first dielectric layer 2; each group of first metal via units includes two first metal vias 21 that are symmetrical about the center of the first patch unit; wherein the first end of the first metal via 21 is connected to the first rectangular metal patch, and the second end of the first metal via 21 is connected to the second metal layer 4 in the second radiation layer.

[0025] The size characteristics of the first radiation layer are as follows: The dimensional characteristics of the larger rectangular metal patch are: length Lp1× Width Wp 1=2.7mm×2.4mm, the size characteristics of the smaller rectangular metal patch are: length Lp 2×Width Wp 2 = 2.4 mm × 1.36 mm; the lateral distance between the larger rectangular metal patch and the center of the first patch unit Lb 1 and longitudinal distance Wb 1 are 0.31 mm and 0.38 mm respectively; the longitudinal distance between the larger rectangular metal patch and the smaller rectangular metal patch Lb 1.9mm; The size characteristics of the first dielectric layer 2 are: L 1× Width W ×Height H 1=22mm×22mm×0.254mm, the radius of the first metal via 21 R 1 is 0.2 mm, and the lateral distance between the center of the first metal via 21 and the center of the first patch unit d 1 and longitudinal distance d 2 are 0.625mm and 0.725mm respectively.

[0026] The first adhesive layer 3 is arranged between the first radiation layer and the second radiation layer; wherein one side of the first adhesive layer 3 is bonded to the first dielectric layer 2 in the first radiation layer, and the other side of the first adhesive layer 3 is bonded to the second metal layer 4 in the second radiation layer, so as to bond the first dielectric layer 2 and the second metal layer 4 together; preferably, the size characteristics of the first adhesive layer 3 are: length L 1× Width W ×Height H 2=22mm×22mm×0.1mm.

[0027] As attached Figure 1-4 As shown in Figure 7, the second radiation layer includes a second metal layer 4 and a second dielectric layer 5, and the second metal layer 4 is arranged on the first surface of the second dielectric layer 5; wherein the second metal layer 4 is used to form a second radiation layer of the antenna array in combination with the second dielectric layer 5, so as to radiate the electromagnetic waves in the dielectric substrate to form electromagnetic waves in the free space; the second dielectric layer 5 is used to form a second radiation layer of the antenna array in combination with the second metal layer 4, so as to convert the electromagnetic waves transmitted in the dielectric substrate of the lower layer into electromagnetic waves of the required frequency to form a directional beam.

[0028] The second metal layer 4 includes four groups of second patch units, which are arranged in two rows and two columns; each group of the second patch units includes two quarter elliptical metal patches; wherein the two quarter elliptical metal patches are symmetrical about the center of the second patch unit, and the center of the two quarter elliptical metal patches is cut by the rotated ellipse. Specifically, the four groups of second patch units are composed of a quarter large elliptical patch cut by a rotated small ellipse; wherein the size characteristics of the large ellipse are: the semi-major axis Px 1× semi-minor axis Py 1=2.6mm×2.2mm, the size characteristics of the small ellipse are: semi-major axis Px 2× semi-minor axis Py 2 = 1.2mm × 0.6mm; the lateral distance from the center of the large ellipse to the center of the second patch unit Lb 2 and longitudinal distance Wb 2 are 2.2 mm and 0.2 mm respectively, the lateral distance between the center of the small ellipse and the center of the second patch unit Lb 3 and longitudinal distance Wb 3 are 2.4mm and 0.4mm respectively; the rotation angle of the small ellipse α is 45°.

[0029] Four groups of second metal via units are arranged on the second dielectric layer 5, and the four groups of second metal via units are symmetrical about the center of the second dielectric layer 5; each group of second metal via units includes two second metal vias 51 symmetrical about the center of the second patch unit and two third metal vias 52 symmetrical about the center of the second patch unit.

[0030] The size characteristics of the second dielectric layer 5 are: L 1× Width W ×Height H 3=22mm×22mm×0.381mm; the characteristic parameters of the second metal via 51 are the same as the characteristic parameters of the first metal via 21, and the second metal via 51 coincides with the first metal via 21; specifically, the radius of the second metal via 51 R 1 is 0.2 mm, and the lateral distance between the center of the second metal via 51 and the center of the second patch unit d 1 and longitudinal distance d 2 are 0.625 mm and 0.725 mm respectively; the radius of the third metal via 52 R 2 is 0.2 mm, and the lateral distance between the center of the third metal via 52 and the center of the second patch unit d 3 and longitudinal distance d 4 are 0.63mm and 0.88mm respectively.

[0031] The second adhesive layer 6 is arranged between the second radiation layer and the third metal layer 7; wherein one side of the second adhesive layer 6 is bonded to the second dielectric layer 5 in the second radiation layer, and the other side of the second adhesive layer 6 is bonded to the third metal layer 7, so as to bond the second dielectric layer 5 and the third metal layer 7 together; preferably, the size characteristics of the second adhesive layer 6 are: length L 1× Width W ×Height H 2=22mm×22mm×0.1mm.

[0032] As attached Figure 1-4 As shown in , 5 and 8, the third metal layer 7 is used to couple the electromagnetic energy in the third dielectric layer 8 to the first dielectric layer 2 and the second dielectric layer 5 through the coupling gap, and at the same time acts as the ground plane of the grounded coplanar waveguide; specifically, the third metal layer 7 includes a metal layer body and a first ground plane 72; the metal layer body and the first ground plane 72 are both arranged on the first surface of the third dielectric layer 8, and the first ground plane 72 is arranged at the end of the metal layer body; the metal layer body is provided with four rectangular gaps 71 arranged in sequence along the center of the metal layer body, and the four rectangular gaps 71 arranged in sequence along the center of the metal layer body are used to realize the circular polarization of the antenna array, and can transmit the electromagnetic energy in the feeding network to the first dielectric layer 2 and the second dielectric layer 5 through gap coupling.

[0033] The size characteristics of the third metal layer 7 are: L 2×Width W ×Height H 4=28mm×22mm×0.035mm, the plane size of the metal layer body is the same as the plane size of the first dielectric layer 2 or the second dielectric layer 5; the size characteristics of the rectangular gap 71 are: length LS × Width W =2.65mm×1.1mm, the lateral distance and longitudinal distance from the center of the rectangular gap 71 to the center of the first dielectric layer 2 or the second dielectric layer 5 L 3 are all 4.4mm.

[0034] It should be noted that the center of the metal layer body coincides with the center of the first dielectric layer 2 and the second dielectric layer 5 , and the centers of the four groups of first patch units, the four groups of second patch units and the four rectangular gaps 71 coincide with each other one by one.

[0035] As attached Figure 1-4As shown, the third dielectric layer 8 is used as a medium for transmitting energy in the feeding network to the coupling gap on the third metal layer 7; the third dielectric layer 8 is provided with a fourth metal via 81, and the fourth metal via 81 is symmetrically arranged about the central axis of the first ground plane 72; one end of the fourth metal via 81 is connected to the first ground plane 72, and the other end of the fourth metal via 81 is connected to the second ground plane 92 in the fourth metal layer 9; wherein the fourth metal via 81 is used for connection between the first ground plane 72 and the second ground plane 92 to achieve consistent grounding performance.

[0036] The size characteristics of the third dielectric layer 8 are: L 2×Width W ×Height H 5=28mm×22mm×0.254mm; the radius of the fourth metal via 81 R 4 is 0.25 mm, and the distance between the center of the fourth metal via 81 and the central axis of the first ground plane 72 is d 5 is 1.5 mm; the distance between two adjacent fourth metal vias 81 located on the same side of the central axis of the first ground plane 72 S is 0.77 mm; wherein the innermost fourth metal via is tangent to the second ground plane 92 .

[0037] As attached Figure 1-4 , 8-9, the fourth metal layer 9 serves as a feeding network for the millimeter-wave broadband circularly polarized antenna array to widen the circularly polarized bandwidth and feed the antenna array, and at the same time serves as two ground planes of a grounded coplanar waveguide; wherein the fourth metal layer 9 comprises a one-to-four microstrip feeding network 91 and a second ground plane 92; the one-to-four microstrip feeding network 91 and the second ground plane 92 are both arranged on the second surface of the third dielectric layer 8, the center of the one-to-four microstrip feeding network 91 coincides with the center of the first radiation layer and the center of the second radiation layer, and the second ground plane 92 coincides with the first ground plane 72 from top to bottom; The one-to-four microstrip feeding network 91 is provided with four output ports, and the output electromagnetic waves of the four output ports differ in phase by 90°, forming a feeding network for sequential rotation feeding; the second ground plane 92 includes two metal ground structures, the two metal ground structures are symmetrically arranged on both sides of the central axis of the first ground plane 72, and the two metal ground structures, the fourth metal via 81 and the first ground plane 72 form a grounded coplanar waveguide; specifically, the size characteristics of each metal ground structure are: length Lp 3×Width Wp 3 = 6mm × 10.14mm; among which, Wp 3= W / 2- W 1, Lp 3= L 1- L 2, W 1 is the distance from the short side of the metal ground structure close to the inner side of the antenna to the central axis of the second ground plane 92.

[0038] It should be noted that the sequential rotation feeding network in the fourth metal layer 9 can broaden the circular polarization bandwidth of the antenna array to form a millimeter-wave broadband circularly polarized magnetoelectric dipole antenna array; the third metal layer 7, the third dielectric layer 8 and the fourth metal layer 9 are all provided with joint mounting through holes, and the joint mounting through holes are used to install solder-free joints; wherein the radius of the joint mounting through holes is R 3 is 1 mm; the thickness of the first metal layer 1, the second metal layer 4, the third metal layer 7 and the fourth metal layer 9 are all H 4. H 4 is 0.035mm.

[0039] Production process: The manufacturing process of the millimeter wave broadband circularly polarized antenna array described in the present invention is as follows: According to the design requirements of the antenna, the PCB manufacturing process is adopted to obtain the dielectric substrate; Based on the grounded coplanar waveguide and magneto-electric dipole technology, a metal layer structure is realized by tinning on the surface of a dielectric substrate to obtain the millimeter-wave broadband circularly polarized antenna array.

[0040] The millimeter-wave broadband circularly polarized antenna array described in the present invention comprises a first metal layer 1, a first dielectric layer 2, a first adhesive layer 3, a second metal layer 4, a second dielectric layer 5, a second adhesive layer 6, a third metal layer 7, a third dielectric layer 8 and a fourth metal layer 9 stacked in sequence; the first metal layer 1 comprises two rectangular patches, the first dielectric layer 2 is provided with a first metal via 21, and the first metal via is symmetrical about the center of the first patch unit; the first metal layer 1 is printed on the first surface of the first dielectric layer 2 to constitute the first radiation layer of the antenna array, which is used to directionally radiate the received electromagnetic waves into free space; wherein the first radiation layer comprises antenna units arranged in rotation along the center of the array, each antenna unit comprising two metal patches, two parasitic patches and two metal vias; The second metal layer 4 is printed on the first surface of the second dielectric layer 5, forming the second radiation layer of the antenna array, which is used to directionally radiate the received electromagnetic waves into the free space; wherein the second radiation layer includes antenna units arranged in rotation along the center of the array, and each antenna unit includes two metal patches and two metal vias; the second metal via 51 and the third metal via 52 in the second dielectric layer 5 are symmetrical about the center of the second patch unit; the third metal layer 7 is printed on the first surface of the third dielectric layer 8, and the fourth metal layer 9 is printed on the second surface of the third dielectric layer 8, forming the feeding structure and the grounded coplanar waveguide structure of the antenna array; the present invention has the advantages of large impedance bandwidth, large axial ratio bandwidth, stable radiation pattern and high efficiency, and realizes the function of a better millimeter-wave broadband circularly polarized antenna array.

[0041] In the present invention, the grounded coplanar waveguide and magnetoelectric dipole technology are used to process the antenna array. The performance of the magnetoelectric dipole antenna is achieved by adding metal vias in the first dielectric layer and the second dielectric layer, and the performance of the grounded coplanar waveguide is achieved by adding metal vias in the third dielectric layer. The advantage of the millimeter-wave magnetoelectric dipole antenna array processed by the grounded coplanar waveguide technology is that the processing technology is mature and the precision is high, which can significantly reduce the processing error and test error of the antenna array.

[0042] As attached Figure 10-11 As shown, attached Fig.10 The return loss and axial ratio of the millimeter wave broadband circularly polarized antenna array are shown in the figure. Fig.11 The gain curve of the millimeter wave broadband circularly polarized antenna array with frequency is given in the figure; Fig.10 It can be seen from the figure that the millimeter wave broadband circularly polarized antenna array is in the frequency range of 24.71-42 GHz |S 11 |<-10dB, the relative bandwidth is 51.84%; the millimeter wave broadband circularly polarized antenna array has an axial ratio AR<3dB in the frequency range of 24-41.82GHz, an axial ratio bandwidth of 54.15%, a frequency range overlapping with the impedance bandwidth of 24.71-41.82GHz, and an overlapping bandwidth of 51.44%; Fig.11 It can be seen that the millimeter-wave broadband circularly polarized antenna array has a gain greater than 9dBic in the frequency range of 24-40GHz, and a maximum gain of 12.89dBic at 30.8GHz.

[0043] As attached Figure 12-19 As shown, attached Figure 12-19 The radiation patterns of the millimeter-wave broadband circularly polarized magnetoelectric dipole antenna array at 26 GHz, 28 GHz, 30 GHz, 32 GHz, 34 GHz, 36 GHz, 38 GHz and 40 GHz are given in the figure; Figure 12-19 It can be seen from the figure that the millimeter wave broadband circularly polarized antenna array has good directivity.

[0044] The millimeter-wave broadband circularly polarized magnetoelectric dipole antenna array described in this embodiment combines the magnetoelectric dipole antenna and the grounded coplanar waveguide technology to achieve precise processing of the magnetoelectric dipole antenna in the millimeter-wave frequency band; it has the characteristics of wide bandwidth, stable radiation pattern, low loss and high processing accuracy; based on the idea of ​​the present invention, the design of the millimeter-wave frequency band antenna can achieve the miniaturization of the antenna and the high processing accuracy of the magnetoelectric dipole antenna.

[0045] In the present invention, a magnetoelectric dipole antenna containing two groups of rotationally symmetric metal patches is used as an antenna unit, and a one-to-four microstrip power divider is used as a feed, thereby finally realizing an easy-to-integrate and easy-to-process millimeter-wave broadband circularly polarized antenna array that can meet the requirements of a millimeter-wave communication system; specifically, the circular polarization performance of the antenna is realized by designing rectangular gaps that rotate sequentially along the center of the antenna, metal vias that are rotationally symmetric along the center of the antenna unit, and metal patches that are rotationally symmetric about the center of the antenna unit on the first metal layer and the second metal layer; a 2×2 circularly polarized array is designed, and a sequentially rotating feeding network is used to feed the circularly polarized array, thereby realizing a millimeter-wave broadband circularly polarized magnetoelectric dipole antenna array; a grounded coplanar waveguide technology is used in combination with a magnetoelectric dipole antenna to realize high processing accuracy of the antenna, and the loss problem of the magnetoelectric dipole antenna in the millimeter-wave frequency band can be well reduced.

[0046] The above embodiment is only one of the implementation methods that can realize the technical solution of the present invention. The scope of protection claimed by the present invention is not limited only to this embodiment, but also includes changes, replacements and other implementation methods that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention.

Claims

1. A millimeter wave broadband circularly polarized antenna array, characterized in that: It comprises a first radiation layer, a second radiation layer, a third metal layer (7), a third dielectric layer (8) and a fourth metal layer (9) which are stacked in sequence; The fourth metal layer (9) is used to receive and transmit electromagnetic waves to the third dielectric layer (8) based on a sequential rotation feeding network; wherein the fourth metal layer (9) is also used to serve as a ground plane of a grounded coplanar waveguide; The third dielectric layer (8) is used to transmit the received electromagnetic wave to the third metal layer (3); wherein the performance of a grounded coplanar waveguide is achieved by introducing metal vias into the third dielectric layer (8); The third metal layer (7) is used to couple the received electromagnetic waves to the first radiation layer and the second radiation layer based on slot coupling; wherein the third metal layer (7) is also used to serve as a ground plane of the grounded coplanar waveguide; The first radiation layer and the second radiation layer are respectively used to directionally radiate the received electromagnetic waves to the free space; wherein, the performance of the magneto-electric dipole antenna is achieved by introducing metal vias into the first radiation layer and the second radiation layer.

2. A millimeter wave broadband circularly polarized antenna array according to claim 1, characterized in that: The first radiation layer comprises a first metal layer (1) and a first dielectric layer (2), wherein the first metal layer (1) is arranged on a first surface of the first dielectric layer (2); The first metal layer (1) comprises four groups of first patch units, which are arranged in a rectangular array; each group of the first patch units comprises four first rectangular metal patches arranged in two rows and two columns; wherein two diagonally arranged first rectangular metal patches have the same structure, and two adjacent first rectangular metal patches have different structures; Four groups of first metal via units are provided on the first dielectric layer (2), and the four groups of first metal via units are symmetrical about the center of the first dielectric layer (2); each group of first metal via units comprises two first metal vias (21) that are symmetrical about the center of the first patch unit; wherein the first end of the first metal via (21) is connected to the first rectangular metal patch, and the second end of the first metal via (21) is connected to the second radiation layer.

3. The millimeter wave broadband circularly polarized antenna array according to claim 1, characterized in that: The second radiation layer comprises a second metal layer (4) and a second dielectric layer (5), wherein the second metal layer (4) is arranged on a first surface of the second dielectric layer (5); The second metal layer (4) comprises four groups of second patch units, which are arranged in two rows and two columns; each group of the second patch units comprises two quarter-elliptical metal patches; wherein the two quarter-elliptical metal patches are symmetrical about the center of the second patch unit, and the center parts of the two quarter-elliptical metal patches are cut by a rotated ellipse; Four groups of second metal via units are provided on the second dielectric layer (5), and the four groups of second metal via units are symmetrical about the center of the second dielectric layer (5); each group of second metal via units comprises two second metal vias (51) symmetrical about the center of the second patch unit and two third metal vias (52) symmetrical about the center of the second patch unit.

4. The millimeter wave broadband circularly polarized antenna array according to claim 1, characterized in that: The third metal layer (7) comprises a metal layer body and a first ground plane (72); the metal layer body and the first ground plane (72) are both arranged on the first surface of the third dielectric layer (8), the center of the metal layer body coincides with the centers of the first radiation layer and the second radiation layer, and the first ground plane (72) is arranged at the end of the metal layer body; wherein the metal layer body is provided with four rectangular slits (71) arranged in rotational order along the center of the metal layer body.

5. A millimeter wave broadband circularly polarized antenna array according to claim 4, characterized in that: The fourth metal layer (9) comprises a one-to-four microstrip feeding network (91) and a second ground plane (92); the one-to-four microstrip feeding network (91) and the second ground plane (92) are both arranged on the second surface of the third dielectric layer (8), and the center of the one-to-four microstrip feeding network (91) coincides with the center of the first radiation layer and the center of the second radiation layer; wherein the one-to-four microstrip feeding network (91) is provided with four output ports, and the output electromagnetic waves of the four output ports differ in phase by 90°.

6. A millimeter wave broadband circularly polarized antenna array according to claim 5, characterized in that: A fourth metal via (81) is provided on the third dielectric layer (8), and the fourth metal via (81) is symmetrically arranged about the central axis of the first ground plane (72); wherein one end of the fourth metal via (81) is connected to the first ground plane (72), and the other end of the fourth metal via (81) is connected to the second ground plane (92).

7. A millimeter wave broadband circularly polarized antenna array according to claim 6, characterized in that: The first ground plane (72), the fourth metal via (81) and the second ground plane (92) form a grounded coplanar waveguide.

8. The millimeter wave broadband circularly polarized antenna array according to claim 6, characterized in that: The third metal layer (7), the third dielectric layer (8) and the fourth metal layer (9) are all provided with joint mounting through holes, and the joint mounting through holes are used for mounting solder-free joints.

9. The millimeter wave broadband circularly polarized antenna array according to claim 1, characterized in that: It also comprises a first adhesive layer (3) and a second adhesive layer (6); the first adhesive layer (3) is used to adhere the first dielectric layer (2) and the second metal layer (4) together; the second adhesive layer (6) is used to adhere the second radiation layer and the third metal layer (7) together.

10. A method for manufacturing a millimeter wave broadband circularly polarized antenna array according to any one of claims 1 to 9, characterized in that: include: According to the design requirements of the antenna, the PCB manufacturing process is adopted to obtain the dielectric substrate; Based on the grounded coplanar waveguide and magneto-electric dipole technology, a metal layer structure is realized by tinning on the surface of a dielectric substrate to obtain the millimeter-wave broadband circularly polarized antenna array.

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