Compact broadband wide-beam dipole antenna array based on high-order mode

Abstract

The invention discloses a compact broadband wide-beam dipole antenna array based on a high-order mode, which comprises two sub-arrays, the two sub-arrays share a dielectric substrate of which the upper surface and the lower surface are partially coated with copper, the equal-amplitude feed is carried out through a one-to-two power division feed structure, the two sub-arrays are bilaterally symmetrical about the central axis of the dielectric substrate, and the upper surface and the lower surface of the dielectric substrate are partially coated with copper. Each sub-array comprises a substrate integrated waveguide cavity and a plurality of pairs of side-by-side dipoles which are connected through a grounding coplanar waveguide, the substrate integrated waveguide cavity is formed by arranging metalized via holes at equal intervals and works in a TE510 high-order mode, the dipoles are placed in the center of the periphery of each electric field loop of the substrate integrated waveguide cavity, and the ground coplanar waveguide is connected with the substrate integrated waveguide cavity. High directivity of an H plane and unilateral radiation with 3dB beam width of an E plane can be obtained by placing the radiation arms of the dipoles according to a radiation field superposition and cancellation rule. The problems that an existing wide-beam antenna is complex in structure, and the technical scheme is difficult to achieve are solved.

Description

Technical Field

[0001] The invention relates to the technical field of wireless communications, and in particular to a compact wide-bandwidth beam dipole antenna array based on high-order modes. Background Art

[0002] With the upgrading of wireless communication systems, antennas, as RF front-end devices that receive and transmit electromagnetic signals, face higher requirements for their electrical and radiation performance. In recent years, with the expansion of civil wireless communication systems and the rapid development of the Internet of Vehicles, how to achieve wide beam technology based on miniaturized and compact antennas has become one of the current research hotspots.

[0003] At present, the commonly used wide beam technical solutions are as follows: 1. Changing the dielectric plate, widening the beam width by increasing the dielectric plate area or folding the floor, but increasing the overall size of the antenna. 2. Loading parasitic elements, introducing vertical currents near the radiating elements by introducing metal walls and short-circuit probes around the antenna, producing more uniform gain over a larger range, but also increasing the complexity of the antenna structure. 3. Current complementation method, through the fusion of electric field modes or the complementary characteristics of the radiation field of magnetic electric dipoles, the unidirectional radiation characteristics of the wide beam are realized. Based on the above technical solutions, considering the comprehensive radiation performance of the antenna, it is of great significance to design an antenna with a simple structure, compactness, wide impedance bandwidth and wide beam.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies and shortcomings of the prior art, and propose a compact wide-bandwidth beam dipole antenna array based on high-order modes, which solves the problems of complex structure and difficult implementation of technical solutions in existing wide-beam antennas. The antenna array operates in the X-band, has a bandwidth of 9.5-10.5 GHz, a relative bandwidth of 10%, and a 3 dB beamwidth of 196° in the E plane, achieving wide impedance matching bandwidth and wide beamwidth characteristics. In addition, the high-order mode antenna array designed using a substrate integrated waveguide cavity structure has the characteristics of low loss and high compactness.

[0006] To achieve the above-mentioned purpose, the technical solution provided by the present invention is as follows: a compact wide-bandwidth beam dipole antenna array based on a high-order mode, comprising two sub-arrays, the two sub-arrays share a dielectric substrate, and are fed with equal amplitude through a one-to-two power-dividing feeding structure, wherein the upper and lower surface portions of the dielectric substrate are partially covered with copper, and the copper-covered portion of the lower surface serves as a floor, the two sub-arrays are bilaterally symmetrical about the central axis of the dielectric substrate, each sub-array comprises a substrate integrated waveguide cavity and a plurality of pairs of dipoles arranged side by side, and are connected by a grounded coplanar waveguide, the substrate integrated waveguide cavity is formed by metallized vias arranged at equal intervals, and works in TE 510 In the high-order mode, a dipole is placed at the center of the periphery of each electric field loop of the substrate integrated waveguide cavity, that is, the upper side of the substrate integrated waveguide cavity away from the feeding port of the one-to-two power-dividing feeding structure and the lower side close to the feeding port, so that the dipoles are arranged in an interval and divided into upper and lower rows, and realize in-phase radiation, the adjacent dipole structures in the upper row are opposite in sequence but the current directions are the same, and the dipole structures in the lower row are the same but the current directions are opposite in sequence, that is, by placing the radiating arms of the dipoles according to the rules of radiation field superposition and destructiveness, high directivity in the H plane and unilateral radiation with a wide 3dB beam width in the E plane can be obtained.

[0007] Furthermore, each dipole includes two left and right opposite radiating arms.

[0008] Furthermore, the dipoles in the upper row are divided into an odd group and an even group according to the order of odd and even numbers, that is, the dipoles belonging to odd numbers are divided into one group, and the dipoles belonging to even numbers are divided into another group, wherein the left radiating arms of the odd group are placed on the upper surface of the dielectric substrate, and the right radiating arms are placed on the lower surface of the dielectric substrate, and both are connected to the copper-clad parts of the upper and lower surfaces respectively by microstrip transmission lines; the left radiating arms of the even group are placed on the lower surface of the dielectric substrate, and the right radiating arms are placed on the upper surface of the dielectric substrate, and both are connected to the copper-clad parts of the lower and upper surfaces respectively by microstrip transmission lines.

[0009] Furthermore, in the subarray located on the left side, the left radiating arm of each dipole in the lower row is placed on the upper surface of the dielectric substrate, and the right radiating arm is placed on the lower surface of the dielectric substrate, and both are connected to the copper-clad parts of the upper and lower surfaces respectively by microstrip transmission lines; in the subarray located on the right side, the left radiating arm of each dipole in the lower row is placed on the lower surface of the dielectric substrate, and the right radiating arm is placed on the upper surface of the dielectric substrate, and both are connected to the copper-clad parts of the lower and upper surfaces respectively by microstrip transmission lines.

[0010] Furthermore, the grounded coplanar waveguide comprises an input grounded coplanar waveguide and an output grounded coplanar waveguide, the input grounded coplanar waveguide connects the substrate integrated waveguide cavity and the feed line of the one-to-two power-dividing feeding structure, and the output grounded coplanar waveguide connects the substrate integrated waveguide cavity and each dipole.

[0011] Furthermore, the input grounded coplanar waveguide and the output grounded coplanar waveguide are Γ-shaped structures.

[0012] Furthermore, the dipole is a half-wavelength dipole.

[0013] Furthermore, the dielectric substrate is a Rogers 4003 dielectric substrate.

[0014] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. The antenna array of the present invention has the advantages of high gain, wide impedance bandwidth and wide beam width, and has compact size, simple structure and low processing cost, and has good application prospects.

[0015] 2. The antenna array of the present invention can achieve in-phase radiation without designing a power distribution network by placing a dipole with differential characteristics in a substrate integrated waveguide cavity of a high-order mode.

[0016] 3. In the subarray of the present invention, the structures of the adjacent dipoles in the upper row are opposite to each other but the current directions are the same, and the structures of the dipoles in the lower row are the same but the current directions are opposite to each other. That is, by placing the dipole radiation arms according to the rules of radiation field superposition and cancellation, high directivity in the H plane and unilateral directional radiation with a wide beam width of 3 dB in the E plane can be obtained. Compared with other methods of realizing wide beams, such as loading parasitic elements and introducing vertical current methods, the implementation difficulty of this technical solution is relatively low. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a three-dimensional diagram of the antenna array of the present invention.

[0018] Figure 2 FIG. 4 is a top view of the antenna array of the present invention.

[0019] Figure 3 It is a bottom view of the antenna array of the present invention.

[0020] Figure 4 Graph showing the simulated S parameters and gain results of the antenna array of the present invention.

[0021] Figure 5 : is the simulated radiation pattern of the antenna array of the present invention. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with specific embodiments.

[0023] See also Figure 1 , 2As shown in Figure 3, this embodiment discloses a compact wide bandwidth beam dipole antenna array based on high-order modes, including two sub-arrays, which share a Rogers 4003 dielectric substrate 1 and are fed with equal amplitude through a one-to-two power splitting feeding structure 9, wherein the upper and lower surfaces of the Rogers 4003 dielectric substrate 1 are partially covered with copper, the black part in the figure is the copper-clad part of the upper surface, marked as 2, and the gray part is the copper-clad part of the lower surface, marked as 3, and the copper-clad part of the lower surface is used as a floor, the two sub-arrays are symmetrical about the central axis of the Rogers 4003 dielectric substrate 1, each sub-array includes a substrate integrated waveguide cavity and 5 pairs of half-wavelength dipoles arranged side by side, and are connected by a grounded coplanar waveguide, which effectively improves the impedance matching characteristics; the substrate integrated waveguide cavity is composed of metallized vias 4 according to the same specific center spacing, and the set size allows it to work at TE 510 High-order mode: A half-wavelength dipole is placed at the center of the outer periphery of each electric field loop of the substrate integrated waveguide cavity, that is, the upper side of the substrate integrated waveguide cavity away from the feeding port of the one-to-two power-dividing feeding structure 9 and the lower side close to the feeding port, and the half-wavelength dipoles are compactly arranged at a spacing of one-fifth of the cavity length, divided into upper and lower rows, and each half-wavelength dipole includes two left and right opposite radiation arms. By utilizing its differential characteristics, the radiation arms of the half-wavelength dipole are regularly arranged to achieve in-phase radiation, without the need to design a power distribution network. The omission of the power distribution network can reduce the size of the subarray and achieve a more compact antenna array aperture; the grounded coplanar waveguide includes a Γ-shaped input grounded coplanar waveguide 5 and a Γ-shaped output grounded coplanar waveguide 6, the Γ-shaped input grounded coplanar waveguide 5 connects the substrate integrated waveguide cavity and the feed line of the one-to-two power division feeding structure 9, the Γ-shaped output grounded coplanar waveguide 6 connects the substrate integrated waveguide cavity and each half-wavelength dipole, and the Γ-shaped structural design increases the schedulability of impedance matching, so that more input energy is radiated outward through the half-wavelength dipole.

[0024] Specifically, the 10 half-wavelength dipoles in the upper row (away from the feeding port side) are divided into odd groups 7-1 to 7-6 and even groups 7-7 to 7-10 according to the odd and even number sorting, that is, the half-wavelength dipoles belonging to odd numbers are divided into one group, and the half-wavelength dipoles belonging to even numbers are divided into another group, wherein the left radiating arms of the odd group are all placed on the upper surface of the Rogers 4003 dielectric substrate 1, and the right radiating arms are placed on the lower surface of the Rogers 4003 dielectric substrate 1, and both are connected to the copper-clad parts 2 and 3 on the upper and lower surfaces respectively by microstrip transmission lines; the left radiating arms of the even group are all placed on the lower surface of the Rogers 4003 dielectric substrate 1, and the right radiating arms are placed on the Rogers The upper surface of the Rogers 4003 dielectric substrate 1 is connected to the copper-clad parts 3 and 2 on the lower and upper surfaces respectively by microstrip transmission lines; the adjacent half-wavelength dipole structures in the upper row are opposite in sequence but have the same phase current distribution, and the radiation field is superimposed in the main radiation direction, which plays a role in enhancing the far-field directivity of the antenna array; the 10 half-wavelength dipoles in the lower row (close to the feeding port side) are divided into two groups 8-1 (i.e., 5 half-wavelength dipoles located in the left subarray) and 8-2 (i.e., 5 half-wavelength dipoles located in the right subarray), wherein the left radiating arm of each half-wavelength dipole located in the left subarray is placed on the upper surface of the Rogers 4003 dielectric substrate 1, and the right radiating arm is placed on the lower surface of the Rogers 4003 dielectric substrate 1, both of which are connected to the copper-clad parts 2 and 3 on the upper and lower surfaces respectively by microstrip transmission lines, and the left radiating arm of each half-wavelength dipole located in the right subarray is placed on the Rogers The right radiating arm is placed on the lower surface of the Rogers 4003 dielectric substrate 1, and the right radiating arm is placed on the upper surface of the Rogers 4003 dielectric substrate 1. Both are connected to the copper-clad parts 3 and 2 on the lower and upper surfaces respectively by microstrip transmission lines. The adjacent dipoles of the two have the same structure but the current distribution is opposite in sequence, which cancels the radiation field of the back lobe of the pattern and obtains a unilateral directional radiation with a wide beam width of 3 dB. Therefore, by placing the radiating arms of the half-wavelength dipole according to the rules of radiation field superposition and cancellation, the high directivity of the H plane and the wide beam of the E plane Huygens antenna pattern can be obtained while significantly reducing the complexity of the antenna array.

[0025] See also Figure 4 As shown, the simulation S parameters and gain results of the antenna array of this embodiment are shown. From the simulation results, it can be seen that the antenna array operates at 9.5-10.5 GHz, with a relative bandwidth of 10%, showing a wide impedance bandwidth transmission characteristic. And the antenna array has a gain greater than 9.11 dBi in 9.5-10.5 GHz, a maximum gain of 11.1 dBi, and a radiation characteristic with stable gain in the passband.

[0026] See also Figure 5As shown, the simulated radiation pattern of the antenna array of this embodiment is shown. From the simulation results, it can be seen that the 3dB beam width of the antenna array in the E plane is 196°, and it has high directivity in the H plane, showing good radiation performance.

[0027] The above-described embodiments are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. Therefore, all changes made according to the shape and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. Compact wide bandwidth dipole antenna array based on high-order modes, characterized in that: The invention comprises two subarrays, the two subarrays share a dielectric substrate (1) and are fed with equal amplitude through a one-to-two power splitting feeding structure (9), wherein the upper and lower surfaces of the dielectric substrate (1) are partially covered with copper, and the copper-covered portion of the lower surface serves as a floor, the two subarrays are bilaterally symmetrical about the central axis of the dielectric substrate (1), each subarray comprises a substrate integrated waveguide cavity and a plurality of pairs of dipoles arranged side by side, and are connected by a grounded coplanar waveguide, the substrate integrated waveguide cavity is formed by metallized vias (4) arranged at equal intervals, and operates at TE 510 In a high-order mode, a dipole is placed at the center of the outer periphery of each electric field loop of the substrate integrated waveguide cavity, that is, the upper side of the substrate integrated waveguide cavity away from the feeding port of the one-to-two power splitting feeding structure (9) and the lower side close to the feeding port, so that the dipoles are arranged in an interval to form an upper and lower row, and realize in-phase radiation, the adjacent dipole structures in the upper row are opposite in sequence but the current directions are the same, and the dipole structures in the lower row are the same but the current directions are opposite in sequence, that is, by placing the radiation arms of the dipoles according to the rules of radiation field superposition and destructiveness, high directivity in the H plane and unilateral radiation with a wide 3dB beam width in the E plane can be obtained.

2. The compact high-order mode-based wide bandwidth dipole antenna array according to claim 1, characterized in that: Each dipole consists of two radiating arms facing left and right.

3. The compact high-order mode-based wide bandwidth dipole antenna array according to claim 2, characterized in that: The dipoles in the upper row are divided into an odd group and an even group according to the order of odd and even numbers, that is, the dipoles belonging to odd numbers are divided into one group, and the dipoles belonging to even numbers are divided into another group, wherein the left radiating arms of the odd group are all placed on the upper surface of the dielectric substrate (1), and the right radiating arms are placed on the lower surface of the dielectric substrate (1), and both are connected to the copper-clad parts of the upper and lower surfaces respectively by microstrip transmission lines; the left radiating arms of the even group are all placed on the lower surface of the dielectric substrate (1), and the right radiating arms are placed on the upper surface of the dielectric substrate (1), and both are connected to the copper-clad parts of the lower and upper surfaces respectively by microstrip transmission lines.

4. The compact high-order mode-based wide bandwidth dipole antenna array according to claim 3, characterized in that: In the subarray located on the left side, the left radiating arm of each dipole in the lower row is placed on the upper surface of the dielectric substrate (1), and the right radiating arm is placed on the lower surface of the dielectric substrate (1), and both are connected to the copper-clad portions of the upper and lower surfaces respectively by microstrip transmission lines; in the subarray located on the right side, the left radiating arm of each dipole in the lower row is placed on the lower surface of the dielectric substrate (1), and the right radiating arm is placed on the upper surface of the dielectric substrate (1), and both are connected to the copper-clad portions of the lower and upper surfaces respectively by microstrip transmission lines.

5. The compact high-order mode-based wide bandwidth beam dipole antenna array according to claim 4, characterized in that: The grounded coplanar waveguide comprises an input grounded coplanar waveguide (5) and an output grounded coplanar waveguide (6), wherein the input grounded coplanar waveguide (5) connects the substrate integrated waveguide cavity and a feed line of a one-to-two power-dividing feeding structure (9), and the output grounded coplanar waveguide (6) connects the substrate integrated waveguide cavity and each dipole.

6. The compact high-order mode-based wide bandwidth dipole antenna array according to claim 5, characterized in that: The input grounded coplanar waveguide (5) and the output grounded coplanar waveguide (6) are of a Γ-shaped structure.

7. The compact high-order mode-based wide bandwidth dipole antenna array according to claim 6, characterized in that: The dipole is a half-wavelength dipole.

8. The compact high-order mode-based wide bandwidth dipole antenna array according to claim 7, characterized in that: The dielectric substrate (1) is a Rogers 4003 dielectric substrate.

Images