A broadband circularly polarized substrate integrated dielectric resonant antenna array

Abstract

The application provides a broadband circularly polarized substrate integrated dielectric resonant antenna array, which comprises a radiation structure and a feed structure; the radiation structure is used for converting a guided electromagnetic wave of the feed structure into a radiation electromagnetic wave in free space and generating a circularly polarized electromagnetic wave; the feed structure is used for transmitting the guided electromagnetic wave to the radiation structure; the radiation structure comprises a first metal layer and a first dielectric layer connected in sequence; the feed structure comprises a second metal layer, a second dielectric layer and a third metal layer connected in sequence, a plurality of cross-shaped crossed slots are arranged on the second metal layer, and a plurality of rotationally symmetrical rectangular slots are arranged on the circumferential side of each cross-shaped crossed slot; and the third metal layer is a one-to-four microstrip feed network. Through cooperation of the radiation structure and the feed structure, the application can meet the working frequency band requirement of millimeter wave mobile communication, and solves the technical problems of a narrow axial ratio bandwidth, a small covered frequency band and poor anti-interference capability of an existing millimeter wave circularly polarized antenna array in a millimeter wave frequency band.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and more specifically to a millimeter-wave broadband circularly polarized substrate integrated dielectric resonant antenna array. Background Technology

[0002] Antennas are a key component of wireless communication systems, primarily serving to convert energy between guided and radiated electromagnetic waves. With the rapid development of 5G mobile communication technology, the spectrum for mobile communication has expanded to the millimeter-wave band, including the n257 (26.5–29.5 GHz) and n260 (37–40 GHz) bands. Most existing mobile communication antenna designs are linearly polarized, making them vulnerable to multipath interference and attenuation effects from rain and fog. In contrast, circularly polarized antennas can suppress multipath interference and counteract the Faraday effect that occurs when electromagnetic waves propagate through the ionosphere, making them highly applicable in next-generation mobile communications.

[0003] However, existing millimeter-wave circularly polarized antennas suffer from relatively narrow impedance bandwidth and axial ratio bandwidth. For example, existing technologies disclose broadband circularly polarized millimeter-wave substrate-integrated metasurface antenna arrays; however, these arrays are patch antennas, and their relative bandwidth from 31 GHz to 39.4 GHz is relatively low at 24%, while their axial ratio bandwidth from 30.3 to 41 GHz is also relatively low at 30%. Therefore, developing millimeter-wave antennas with circular polarization, wide bandwidth, and small size is essential. Summary of the Invention

[0004] To address the technical problems of existing millimeter-wave circularly polarized antenna arrays, such as narrow axial ratio bandwidth, limited frequency coverage, and poor anti-interference capability in the millimeter-wave band, this invention aims to provide a millimeter-wave broadband circularly polarized substrate-integrated dielectric resonant antenna array. This invention employs a dielectric resonant antenna with a rotationally symmetric connecting bridge as the antenna element and a 1-to-4 microstrip power divider as the feed, ultimately achieving a 2×2 millimeter-wave broadband circularly polarized substrate-integrated dielectric resonant antenna array that is easy to integrate and fabricate, meeting the requirements of millimeter-wave communication systems.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows.

[0006] A broadband circularly polarized substrate integrated dielectric resonant antenna array includes a radiating structure and a feeding structure;

[0007] The radiation structure is used to convert the guided electromagnetic waves of the feeding structure into radiated electromagnetic waves in free space and generate circularly polarized electromagnetic waves.

[0008] The feeding structure is used to transmit guided electromagnetic waves to the radiating structure and broaden the axial ratio bandwidth.

[0009] The radiating structure includes a first metal layer and a first dielectric layer connected in sequence. Multiple antenna elements are arranged on the first dielectric layer, and each antenna element is provided with rotationally symmetrical dielectric bridges.

[0010] The power supply structure includes a second metal layer, a second dielectric layer and a third metal layer connected in sequence. The second metal layer is provided with a plurality of cross-shaped slots, and each cross-shaped slot is provided with a plurality of rotationally symmetrical rectangular slots on its periphery. The third metal layer is a microstrip power supply network that is divided into four parts.

[0011] Furthermore, the first metal layer is printed on the upper surface of the first dielectric layer, the second metal layer is printed on the upper surface of the second dielectric layer, and the third metal layer is printed on the lower surface of the second dielectric layer.

[0012] Furthermore, the outer dimensions of the first metal layer are 18mm × 18mm; the internal hollow dimensions of the first metal layer are 6.8mm × 6.7mm.

[0013] The dimensions of the first dielectric layer are 30mm × 30mm × 1.25mm;

[0014] The dimensions of the second metal layer are 35mm × 30mm;

[0015] The dimensions of the second dielectric layer are 35mm × 30mm × 0.254mm.

[0016] Furthermore, the third metal layer is used to transmit guided electromagnetic waves and broaden the axial ratio bandwidth;

[0017] The second dielectric layer is used to transmit the guided electromagnetic waves output from the third metal layer to the second metal layer;

[0018] The second metal layer is used to transmit the guided electromagnetic wave transmitted by the second dielectric layer to the first dielectric layer through the coupling gap;

[0019] The first dielectric layer and the first metal layer together constitute the radiation structure, which is used to convert the guided electromagnetic wave coupled and transmitted by the second metal layer into a radiated electromagnetic wave that is directionally radiated in free space, and to generate a circularly polarized electromagnetic wave.

[0020] Furthermore, four antenna elements are arranged on the first dielectric layer; four coupling slot structures are arranged on the second metal layer, and the position of each coupling slot structure corresponds one-to-one with the position of its corresponding antenna element.

[0021] Furthermore, the one-to-four microstrip feed network has four output ports, and the position of each output port corresponds one-to-one with the position of its corresponding coupling slot structure.

[0022] The guiding electromagnetic waves output from the four output ports are 90° out of phase, forming a sequentially fed power supply network.

[0023] Furthermore, each of the coupling slot structures consists of a cross-shaped slot and four rectangular slots distributed rotationally symmetrically along the periphery of the cross-shaped slot; the multiple cross-shaped slots are radially distributed circumferentially.

[0024] Furthermore, the cross-shaped gap includes a first gap and a second gap; the first gap is radially distributed, the second gap is perpendicularly disposed on the first gap, and the length of the first gap is greater than the length of the second gap.

[0025] Furthermore, the dimensions of the first gap are 3.94mm × 0.5mm; the dimensions of the second gap are 1.69mm × 0.38mm; and the dimensions of the rectangular gap are 3mm × 0.39mm.

[0026] Furthermore, each antenna element includes, from the outside in, a metal via, an outer ring cutout, a dielectric ring, an inner ring cutout, and a dielectric block;

[0027] Multiple metal vias are arranged to form a rectangular substrate integrated waveguide cavity;

[0028] The outer ring is hollowed out and is provided with a circular polarization connecting bridge and a dielectric ring connecting bridge. Both the circular polarization connecting bridge and the dielectric ring connecting bridge are connected to the dielectric ring. Both the circular polarization connecting bridge and the dielectric ring connecting bridge are connected to the first dielectric layer.

[0029] The inner ring is hollowed out and a medium block connecting bridge is provided. The medium block connecting bridge is connected to the medium ring and the medium block respectively.

[0030] Furthermore, the width of the circularly polarized connecting bridge is 0.6mm × 0.68mm × 1.25mm;

[0031] The dimensions of the dielectric ring connecting bridge are 0.6mm × 0.5mm × 1.25mm;

[0032] The dimensions of the cutout in the outer ring are 3.66mm × 3.7mm × 1.25mm;

[0033] The dimensions of the dielectric ring are 3.06mm × 3.1mm × 1.25mm;

[0034] The width of the medium block connecting bridge is 0.5 mm; the width of the inner ring cutout is 0.6 mm;

[0035] The dimensions of the medium block are 2.46mm × 2.5mm × 1.25mm.

[0036] This invention also provides a fabrication process for a broadband circularly polarized substrate-integrated dielectric resonant antenna array, as detailed below:

[0037] According to the antenna design requirements, the antenna substrate is fabricated using PCB manufacturing technology;

[0038] By using substrate integrated waveguide technology, metal vias are added to the antenna array, and copper is plated and tin is deposited on the surface of the dielectric substrate to realize the metal layer structure, thereby obtaining the broadband circularly polarized substrate integrated dielectric resonant antenna array.

[0039] The beneficial effects of this invention are:

[0040] 1. This invention combines dielectric resonant antenna and substrate integrated waveguide technology. The feeding structure features a cross-shaped coupling slot, a rectangular slot rotating sequentially along the center of the antenna element, and a sequentially fed one-to-four microstrip feeding network. The radiating structure incorporates a rotationally symmetrical dielectric bridge on a dielectric ring to achieve broadband circular polarization performance, meeting the operating frequency requirements of millimeter-wave mobile communication. It features wide impedance bandwidth, wide axial ratio bandwidth, and small antenna size. The device boasts high processing precision and low manufacturing cost. This invention solves the technical problems of existing millimeter-wave circularly polarized antenna arrays, which suffer from narrow axial ratio bandwidth, limited frequency coverage, and poor anti-interference capabilities in the millimeter-wave band.

[0041] 2. This invention uses a dielectric resonant antenna with a rotationally symmetric connecting bridge as the antenna element and a microstrip power divider with a 1-to-4 splitter as the feed, ultimately realizing a 2×2 millimeter-wave broadband circularly polarized substrate integrated dielectric resonant antenna array that can be easily integrated and fabricated to meet the requirements of millimeter-wave communication systems.

[0042] 3. This invention primarily achieves the advantages of large impedance bandwidth, large axial ratio bandwidth, and small antenna size through the first dielectric layer. The broadband circularly polarized substrate-integrated dielectric resonant antenna array operates within the frequency range of 27.86GHz-44GHz. 11 |<-10dB, with a relative bandwidth of 44.92%. The broadband circularly polarized substrate integrated dielectric resonant antenna array has an axial ratio AR <3dB and an axial ratio bandwidth of 48.80% in the frequency range of 25.13GHz-41.35GHz. The frequency range overlapping with the impedance bandwidth is 27.86GHz-41.35GHz, with a relative bandwidth of 38.98%. Attached Figure Description

[0043] Figure 1This is a schematic diagram of the three-dimensional layered structure of the antenna array in the embodiment.

[0044] Figure 2 The following are three views and detailed dimensions of the antenna array in the embodiment: (a) top view, (b) including the middle layer and the bottom layer, and (c) side view.

[0045] Figure 3 This is the first metal layer of the antenna array in the embodiment.

[0046] Figure 4 This is the first dielectric layer of the antenna array in the embodiment.

[0047] Figure 5 This is the second metal layer of the antenna array in the embodiment.

[0048] Figure 6 The detailed dimensions of the antenna element in the embodiment are shown in (a) the first dielectric layer, and (b) the second and third metal layers.

[0049] Figure 7 This is a schematic diagram of the feed network layer structure of the antenna array in the embodiment.

[0050] Figure 8 The example shows the return loss of the antenna array.

[0051] Figure 9 The axial ratio of the antenna array in this embodiment is shown.

[0052] Figure 10 The figure shows the gain of the antenna array as a function of frequency in the embodiment.

[0053] Figure 11 In this embodiment, the antenna array is at 28 GHz. and The radiation pattern.

[0054] Figure 12 In this embodiment, the antenna array is at 30 GHz. and The radiation pattern.

[0055] Figure 13 In this embodiment, the antenna array is at 32 GHz. and The radiation pattern.

[0056] Figure 14 In this embodiment, the antenna array is located at 34 GHz. and The radiation pattern.

[0057] Figure 15 In this embodiment, the antenna array is at 36 GHz. and The radiation pattern.

[0058] Figure 16 In this embodiment, the antenna array is at 38 GHz. and The radiation pattern.

[0059] Figure 17 In this embodiment, the antenna array is at 40 GHz. and The radiation pattern.

[0060] In the figure, 1. First metal layer; 2. First dielectric layer; 21. Metal via; 22. Circular polarization connection bridge; 23. Dielectric ring connection bridge; 24. Outer ring cutout; 25. Dielectric ring; 26. Dielectric block connection bridge; 27. Inner ring cutout; 28. Dielectric block; 3. Second metal layer; 31. Cross-shaped slot; 311. Second slot; 312. First slot; 32. Rectangular slot; 33. Ground plane; 4. Second dielectric layer; 5. Third metal layer. Detailed Implementation

[0061] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0062] Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] Please see Figures 1 to 7 A broadband circularly polarized substrate-integrated dielectric resonant antenna array includes a radiating structure and a feeding structure. The radiating structure is used to convert the guided electromagnetic waves of the feeding structure into radiated electromagnetic waves in free space and generate circularly polarized electromagnetic waves; the feeding structure is used to transmit the guided electromagnetic waves to the radiating structure and broaden the axial ratio bandwidth.

[0064] The radiating structure includes a first metal layer 1 and a first dielectric layer 2 connected in sequence. The first metal layer 1 is printed on the upper surface of the first dielectric layer 2. The first metal layer 1 and the first dielectric layer 2 together form the radiating structure of the antenna array, converting guided electromagnetic waves in the lower dielectric substrate into radiated electromagnetic waves in free space, and exhibiting circularly polarized radiation characteristics. Multiple dielectric ring structures 25 are arranged on the first dielectric layer 2, and each dielectric ring 25 structure is evenly distributed with rotationally symmetrical dielectric bridges. In this embodiment, the protrusions of the first dielectric layer 2 are used to generate high-frequency circular polarization and to connect the separate dielectric rings and dielectric blocks together.

[0065] The feeding structure includes a second metal layer 3, a second dielectric layer 4, and a third metal layer 5 connected in sequence. The second metal layer 3 is printed on the upper surface of the second dielectric layer 4, and the third metal layer 5 is printed on the lower surface of the second dielectric layer 4. The second metal layer 3, the second dielectric layer 4, and the third metal layer 5 together constitute the feeding structure of the antenna radiation structure and have the characteristic of widening the axial ratio bandwidth of the array antenna. Multiple cross-shaped slots 31 are arranged on the second metal layer 3, and multiple rotationally symmetrical rectangular slots 32 are evenly distributed around the periphery of each cross-shaped slot 31. The second dielectric layer 4 is an energy transmission structure used to transmit energy from the feeding network to the first dielectric layer 2 through coupling slots. The third metal layer 5 is a one-to-four microstrip feeding network.

[0066] The first dielectric layer 2 and the first metal layer 1 combine to form a radiating structure, used to convert the guided electromagnetic waves coupled and transmitted by the second metal layer 3 into radiated electromagnetic waves that are directionally radiated in free space, and to generate circularly polarized electromagnetic waves. The second metal layer 3 is used to transmit the guided electromagnetic waves transmitted by the second dielectric layer 4 to the first dielectric layer 2 through coupling gaps. The second dielectric layer 4 is used to transmit the guided electromagnetic waves output from the third metal layer 5 to the second metal layer 3; it also serves as the dielectric for transmitting energy from the feed network to the coupling window on the second metal layer 3. The third metal layer 5 is used to transmit guided electromagnetic waves and broaden the axial ratio bandwidth. Specifically, the third metal layer 5 is used in the feed network of the broadband circularly polarized substrate integrated dielectric antenna array, broadening the circular polarization bandwidth and feeding the antenna array.

[0067] The radiating structure includes antenna elements arranged rotating around the array center. Each antenna element includes a rectangular dielectric block, a rectangular dielectric ring, and six connected dielectric bridges. A second metal layer has slots corresponding to the antenna elements, used to transmit electromagnetic waves from the second dielectric layer to the radiating layer. The third metal layer is a sequentially rotating power distribution network, which utilizes a microstrip structure to form a 1-to-4 power distribution network with adjacent ports having a 90° phase difference. The antenna array of this embodiment has a large impedance bandwidth (e.g., Figure 8 ), with a large axial bandwidth (e.g.) Figure 9 It has the advantage of small antenna size, which enables it to achieve better broadband circularly polarized antenna array functionality.

[0068] Four dielectric rings 25 are arranged on the first dielectric layer 2; four coupling slot structures are arranged on the second metal layer 3, with the position of each coupling slot structure corresponding one-to-one with the position of its corresponding dielectric ring 25 structure. The second metal layer includes a ground plane 33, which is located on one side of the four coupling slot structures. The one-to-four microstrip feed network has four output ports, with the position of each output port corresponding one-to-one with the position of its corresponding coupling slot structure. The guiding electromagnetic waves output from the four output ports are 90° out of phase, forming a sequentially fed feed network.

[0069] Each dielectric ring 25 structure includes, from the outside in, a metal via 21, an outer ring cutout 24, a dielectric ring 25, an inner ring cutout 27, and a dielectric block 28. Multiple metal vias 21 are arranged to form a rectangular substrate integrated waveguide cavity. The outer ring cutout 24 is provided with a circularly polarized connecting bridge 22 and a dielectric ring 25 connecting bridge 23, both of which are connected to the dielectric ring 25. Both the circularly polarized connecting bridge 22 and the dielectric ring 25 connecting bridge 23 are connected to the first dielectric layer 2. The inner ring cutout 27 is provided with a dielectric block 28 connecting bridge 26, which is connected to the dielectric ring 25 and the dielectric block 28, respectively.

[0070] Each coupling slot structure consists of a cross-shaped slot 31 and four rectangular slots 32 distributed rotationally symmetrically along the periphery of the cross-shaped slot 31; the multiple cross-shaped slots 31 are radially distributed. The cross-shaped slots 31 include a first slot 312 and a second slot 311; the first slot 312 is radially distributed, and the second slot 311 is perpendicularly disposed on the first slot 312, the length of the first slot 312 being greater than the length of the second slot 311. The first slot 312 is a long rectangular slot, and the second slot 311 is a short rectangular slot. The cross-shaped slots 31 and the rectangular slots 32 are used to couple energy from the second dielectric layer 4 into the first dielectric layer 2.

[0071] The broadband circularly polarized dielectric resonant antenna array described in this embodiment combines dielectric resonant antenna and substrate integrated waveguide technology to achieve precise fabrication of dielectric resonant antennas in the millimeter-wave band. It features wide bandwidth, high fabrication accuracy, and low cost. Through the approach of this embodiment, the design of a dielectric resonant antenna in the millimeter-wave band can achieve antenna miniaturization and high fabrication accuracy.

[0072] In this embodiment, the circular polarization performance of the antenna is achieved by designing cross-shaped coupling slots, rectangular slots that rotate sequentially along the center of the antenna element, and a rotationally symmetrical dielectric bridge on the antenna dielectric ring. A 2×2 circular polarization array is designed, and a sequentially rotating feed network is used to feed the circular polarization array to realize a broadband circular polarization dielectric resonant antenna array. The substrate integrated waveguide technology is combined with the dielectric resonant antenna to achieve high processing accuracy and low processing cost, which can effectively reduce the processing accuracy problem of dielectric resonant antennas in the millimeter-wave band.

[0073] Below, we will provide a detailed explanation of the structure of a broadband circularly polarized substrate integrated dielectric resonant antenna array.

[0074] Example 1

[0075] like Figure 1-7This embodiment provides a broadband circularly polarized substrate-integrated dielectric resonant antenna array, comprising, from top to bottom, a first metal layer 1, a first dielectric layer 2, a second metal layer 3, a second dielectric layer 4, and a third metal layer 5. The first metal layer 1, combined with the first dielectric layer 2, forms the radiating layer of the antenna array, radiating electromagnetic waves from the dielectric substrate into free-space electromagnetic waves. The first dielectric layer 2, combined with the first metal layer 1, forms the radiating layer of the antenna array, converting electromagnetic waves transmitted from the lower dielectric substrate into electromagnetic waves of the desired frequency, forming a directional beam. The second metal layer 3 couples the electromagnetic energy from the second dielectric layer 4 to the first dielectric layer 2 through coupling gaps. The second dielectric layer 4 serves as the dielectric for transmitting energy from the feed network to the coupling window on the second metal layer 3. The third metal layer 5 forms the feed network for the broadband circularly polarized substrate-integrated dielectric antenna array, widening the circular polarization bandwidth and feeding the antenna array. Figure 2 As shown, the dimensions of the first dielectric layer 2 are: length W1 × width W1 × height t1 = 30mm × 30mm × 1.25mm; the dimensions of the second metal layer 3 are: length L1 × width W1 = 35mm × 30mm; the dimensions of the second dielectric layer 4 are: length L1 × width W1 × height t2 = 35mm × 30mm × 0.254mm. Figure 3 As shown, the outer dimensions of the first metal layer 1 are: length L2 × width W2 = 18mm × 18mm, and the inner dimensions of the first metal layer are: length L3 × width W3 = 6.8mm × 6.7mm.

[0076] like Figure 4 As shown, in this embodiment, the first dielectric layer 2 includes a metal via 21, a circularly polarized connecting bridge 22, a dielectric ring connecting bridge 23, an outer ring cutout 24, a dielectric ring 25, a dielectric block connecting bridge 26, an inner ring cutout 27, and a dielectric block 28. Specifically, the metal vias are arranged to form a rectangular substrate integrated waveguide cavity, confining electromagnetic waves within the rectangular waveguide cavity. The circularly polarized connecting bridge and the dielectric ring connecting bridge are connected to the dielectric ring and the first dielectric layer, located in the outer ring cutout, wherein the circularly polarized connecting bridge is used to broaden the high-frequency circular polarization bandwidth of the antenna. The dielectric block connecting bridge is connected to the dielectric ring and the dielectric block, located in the inner ring cutout. A first metal layer is printed on the upper surface of the first dielectric layer, constituting the radiation structure of the antenna array, used to directionally radiate the electromagnetic waves received by the feed layer into free space.

[0077] like Figure 6As shown in (a), the radius R1 of the metal via 21 is 0.3 mm, and the distance d1 between the centers of the two metal vias is 0.83 mm; the width dimension of the circular polarization connecting bridge 22 is: length Wn1 × width W4 × height t1 = 0.6 mm × 0.68 mm × 1.25 mm; the dimension of the dielectric ring connecting bridge 23 is: length Wn1 × width W5 × height t1 = 0.6 mm × 0.5 mm × 1.25 mm; the dimension of the outer ring cutout 24 is: length L 3×width W6×height t1=3.66mm×3.7mm×1.25mm; the dimensions of the medium ring 25 are: length L4×width W7×height t1=3.06mm×3.1mm×1.25mm; the width W8 of the medium block connecting bridge 26 is 0.5mm; the width Wn2 of the inner ring hollow 27 is 0.6mm; the dimensions of the medium block 28 are: length L5×width W9×height t1=2.46mm×2.5mm×1.25mm.

[0078] like Figure 5 As shown, the second metal layer 3 includes a cross-shaped slot 31, a rectangular slot 32, and a ground plane 33. The cross-shaped slot and the four rectangular slots 32 arranged in sequence around the center of the antenna element are used to realize the circular polarization of the antenna and can transmit the energy in the feed network to the first dielectric layer through the coupling slots. Specifically, the cross-shaped slot 31 includes a short rectangular slot 311 and a long rectangular slot 312.

[0079] like Figure 6 As shown in (b), in the cross-shaped gaps 31, the dimensions of the short rectangular gap 311 are: length Ls1 × width Ws1 = 1.69 mm × 0.38 mm, the dimensions of the long rectangular gap 312 are: length Ls2 × width Ws2 = 3.94 mm × 0.5 mm, and the included angle between the short rectangular gap 311 and the long rectangular gap 312 is 90°; the dimensions of the rectangular gap 32 are: length Ls3 × width Ws3 = 3 mm × 0.39 mm.

[0080] like Figure 7 As shown, the third metal layer 5 is a one-to-four microstrip feed network with four output ports. The output electromagnetic waves of the four ports are 90° out of phase, forming a sequential feed network. Specifically, the second metal layer 3 is printed on the upper surface of the second dielectric layer 4, and the third metal layer 5 is printed on the lower surface, forming the feed structure of the antenna array. The sequential rotation feed network can broaden the circular polarization bandwidth of the antenna array, forming a broadband circularly polarized substrate integrated dielectric resonant antenna array.

[0081] The fabrication process of the broadband circularly polarized substrate integrated dielectric resonant antenna array in this embodiment is as follows:

[0082] According to the antenna design requirements, the antenna substrate is fabricated using PCB manufacturing technology;

[0083] By using substrate integrated waveguide technology, metal vias are added to the antenna array, and a metal layer structure is achieved by immersion tin on the surface of the dielectric substrate, thus obtaining the broadband circularly polarized substrate integrated dielectric resonant antenna array.

[0084] In this embodiment, the antenna array is fabricated using substrate integrated waveguide technology. The rectangular waveguide performance is achieved by adding metal vias around the dielectric block. The advantages of millimeter-wave dielectric resonant antenna arrays fabricated using substrate integrated waveguide technology are that the fabrication process is mature and the precision is high, which can significantly reduce the fabrication and testing errors of the antenna array.

[0085] Figure 8 The simulation results of the reflection coefficient of the broadband circularly polarized substrate integrated dielectric resonant antenna array are presented in the figure. Figure 8 As can be seen from the data, the broadband circularly polarized substrate integrated dielectric resonant antenna array operates within the frequency range of 27.86 GHz to 44 GHz. 11 |<-10dB, relative bandwidth is 44.92%.

[0086] Figure 9 The simulation results of the axial ratio of the broadband circularly polarized substrate integrated dielectric resonant antenna array as a function of frequency are given in the appendix. Figure 9 It can be seen that the broadband circularly polarized substrate integrated dielectric resonant antenna array has an axial ratio AR < 3dB in the frequency range of 25.13GHz-41.35GHz, an axial ratio bandwidth of 48.80%, and a frequency range that overlaps with the impedance bandwidth of 27.86GHz-41.35GHz, with a relative bandwidth of 38.98%.

[0087] Figure 10 The simulation results of the gain of the broadband circularly polarized substrate integrated dielectric resonant antenna array as a function of frequency are given in the figure; from Figure 10 It can be seen that the broadband circularly polarized substrate integrated dielectric resonant antenna array has a gain greater than 6.9 dBi in the frequency range of 26 GHz to 42 GHz, and a maximum gain of 12 dBi at 29 GHz.

[0088] Figure 11-17 The above describes the broadband circularly polarized substrate-integrated dielectric resonant antenna array at 28 GHz, 30 GHz, 32 GHz, 34 GHz, 36 GHz, 38 GHz, and 40 GHz. and The long-range radiation pattern; from Figure 11-17 It can be seen that the broadband circularly polarized substrate integrated dielectric resonant antenna array has good directivity.

[0089] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A broadband circularly polarized substrate-integrated dielectric resonant antenna array, characterized in that, Includes radiating structures and feeding structures; The radiation structure is used to convert the guided electromagnetic waves of the feeding structure into radiated electromagnetic waves in free space and generate circularly polarized electromagnetic waves. The feeding structure is used to transmit guided electromagnetic waves to the radiating structure and broaden the axial ratio bandwidth. The radiating structure includes a first metal layer and a first dielectric layer connected in sequence. Multiple antenna elements are arranged on the first dielectric layer, and each antenna element is provided with rotationally symmetrical dielectric bridges. The power feeding structure includes a second metal layer, a second dielectric layer and a third metal layer connected in sequence. The second metal layer is provided with a plurality of cross-shaped slots, and each cross-shaped slot is provided with a plurality of rotationally symmetrical rectangular slots on its periphery. The third metal layer is a microstrip power feeding network that is divided into four parts. Four antenna elements are arranged on the first dielectric layer; four coupling slot structures are arranged on the second metal layer, and the position of each coupling slot structure corresponds one-to-one with the position of its corresponding antenna element; each coupling slot structure consists of a cross-shaped slot and four rectangular slots that are rotationally symmetrically distributed along the periphery of the cross-shaped slot. The microstrip feed network with a 1-to-4 split has four output ports, and the position of each output port corresponds one-to-one with the position of its corresponding coupling slot structure; the guiding electromagnetic waves output by the four output ports are 90° out of phase, forming a sequential feed network. Each antenna element comprises, from the outside in, a metal via, an outer ring cutout, a dielectric ring, an inner ring cutout, and a dielectric block; the multiple metal vias are arranged to form a rectangular substrate integrated waveguide cavity; the outer ring cutout is provided with a circular polarization connecting bridge and a dielectric ring connecting bridge, both of which are connected to the dielectric ring; both the circular polarization connecting bridge and the dielectric ring connecting bridge are connected to the first dielectric layer; the inner ring cutout is provided with a dielectric block connecting bridge, which is connected to the dielectric ring and the dielectric block respectively.

2. The broadband circularly polarized substrate integrated dielectric resonant antenna array according to claim 1, characterized in that, The first metal layer is printed on the upper surface of the first dielectric layer, the second metal layer is printed on the upper surface of the second dielectric layer, and the third metal layer is printed on the lower surface of the second dielectric layer.

3. The broadband circularly polarized substrate integrated dielectric resonant antenna array according to claim 1, characterized in that, The third metal layer is used to transmit guided electromagnetic waves and broaden the axial ratio bandwidth. The second dielectric layer is used to transmit the guided electromagnetic waves output from the third metal layer to the second metal layer; The second metal layer is used to transmit the guided electromagnetic wave transmitted by the second dielectric layer to the first dielectric layer through the coupling gap; The first dielectric layer and the first metal layer together constitute the radiation structure, which is used to convert the guided electromagnetic wave coupled and transmitted by the second metal layer into a radiated electromagnetic wave that is directionally radiated in free space, and to generate a circularly polarized electromagnetic wave.

4. The broadband circularly polarized substrate integrated dielectric resonant antenna array according to claim 1, characterized in that, The multiple cross-shaped slots are radially distributed along the circumference.

5. The broadband circularly polarized substrate integrated dielectric resonant antenna array according to claim 1, characterized in that, The cross-shaped gap includes a first gap and a second gap; the first gap is radially distributed, and the second gap is perpendicularly disposed on the first gap, and the length of the first gap is greater than the length of the second gap.

Images