A directional pattern reconfigurable antenna array with high gain end-fire beam

Abstract

The application belongs to the technical field of antennas, and particularly relates to a directional pattern reconfigurable antenna array with high-gain end-fire beams. The application comprises a dielectric substrate, a pair of high-gain directional pattern reconfigurable end-fire antennas printed on the upper surface of the dielectric substrate, a switchable feeding structure, a rectangular metal ground printed on the lower surface of the dielectric substrate; the pair of high-gain directional pattern reconfigurable end-fire antennas are respectively connected with the switchable feeding structure and symmetrically arranged on the upper surface of the dielectric substrate about the vertical center line of the switchable feeding structure; each of the pair of high-gain directional pattern reconfigurable end-fire antennas comprises a dielectric resonator, a metal dipole, a transmission line and a matching branch; the dielectric resonator is covered above the metal dipole; the switchable feeding structure has six different working states of state one to state six, and the switching of the six different high-gain end-fire beams is realized by changing the on-off states of the four PIN diodes embedded in the switchable feeding structure.

Description

Technical Field

[0001] This invention belongs to the field of antenna technology, specifically relating to a pattern-reconfigurable antenna array with a high-gain end-fire beam. Background Technology

[0002] Reconfigurable pattern antennas, as an efficient beam control scheme, can largely overcome the shortcomings of traditional phased arrays, such as large size, high complexity, and high loss, achieving beam control with a simple and compact structure. With the development of PCB manufacturing technology, switching technology, and related technologies in recent years, more and more reconfigurable antennas utilize devices such as PIN diodes, varactor diodes, and MEMS switches to achieve reconfigurable antenna parameters by electronically changing the switching states, thus expanding the application areas of reconfigurable technology. However, existing reconfigurable pattern antennas generally suffer from defects in radiation performance. Taking end-fire beams as an example, existing reconfigurable pattern antennas often provide low gain and lack good front-to-back ratio.

[0003] In applications such as tunnels, highways, and vehicles, bidirectional end-fire beam coverage is required to meet communication needs in both directions. Existing bidirectional end-fire antennas often struggle to achieve high-gain bidirectional end-fire within compact spaces, significantly limiting their effective communication range. Furthermore, fixed beams are highly susceptible to electromagnetic interference outside the target direction, degrading communication quality. To ensure effective communication range and quality in these scenarios, a controllable end-fire beam capable of bidirectional coverage is indispensable. Summary of the Invention

[0004] This invention addresses the problems existing in the aforementioned technologies by proposing a pattern-reconfigurable antenna array with a high-gain end-fire beam. The purpose of this invention is to overcome the shortcomings of existing pattern-reconfigurable end-fire antennas, which generally suffer from poor radiation performance and difficulty in achieving bidirectional end-fire coverage.

[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0006] A reconfigurable antenna array with a high-gain end-fire beam pattern includes a dielectric substrate, a pair of high-gain reconfigurable end-fire antennas printed on the upper surface of the dielectric substrate, a switchable feed structure, and a rectangular metal ground plane printed on the lower surface of the dielectric substrate. The vertical projection plane of the switchable feed structure lies on the plane of the rectangular metal ground plane. The pair of high-gain reconfigurable end-fire antennas are respectively connected to the switchable feed structure and are arranged symmetrically about the vertical centerline of the switchable feed structure on the upper surface of the dielectric substrate. Each of the pair of high-gain reconfigurable end-fire antennas includes a dielectric resonator. The device comprises a dielectric resonator, a metal dipole, a transmission line, and a matching stub; the dielectric resonator covers the metal dipole; the metal dipole, transmission line, and matching stub are symmetrically arranged about the horizontal centerline of the dielectric substrate; one end of the transmission line is connected to the metal dipole; the other end of the transmission line is connected to a switchable feed structure; one side of the transmission line is connected to a matching stub; the switchable feed structure has six different operating states from state one to state six, and six different high-gain end-fire beams can be switched by changing the on / off state of the four PIN diodes embedded in the switchable feed structure.

[0007] Furthermore, as a preferred embodiment of the present invention, the dielectric resonator is cuboid in shape and operates at TE. 2δ1 The pattern, together with the metal dipole located below it, forms a controllable electromagnetic dipole pair to obtain a switchable high-gain end-fire beam.

[0008] As a further preferred embodiment of the present invention, the switchable power supply structure includes a main transmission line, four symmetrically arrayed coupling transmission lines on both sides of the main transmission line, an input port, a first output port, a second output port, a third output port, and a fourth output port; one end of the main transmission line is open-circuited, and the other end is connected to the input port through a thin metal wire; one end of the coupling transmission line is connected to the corresponding first to fourth output ports through bent thin wires, and the other end is connected to the first pad through a DC blocking capacitor; the first pad and the ground pad are connected through a PIN diode, with the cathode of the PIN diode connected to the ground pad and the anode connected to the first pad; a choke inductor is connected between the first pad and the second pad, and a DC power supply is connected to the second pad to control the on / off state of the corresponding PIN diode.

[0009] As a further preferred embodiment of the present invention, when a suitable positive bias voltage is applied to the second pad connected to the coupling transmission line, the corresponding PIN diode connected to the coupling transmission line is in the conducting state, and at this time the first output port to the fourth output port connected to the coupling transmission line is turned on.

[0010] When no voltage is applied to the second pad connected to the coupling transmission line, the corresponding PIN diode connected to the coupling transmission line is in the off state. At this time, the first output port to the fourth output port connected to the coupling transmission line is disconnected. By adjusting the DC voltage applied to the four second pads, four states can be achieved: one of the first output port to the fourth output port is turned on; the first output port and the second output port on the same side are turned on, while the third output port and the fourth output port on the other side are turned off; or the third output port and the fourth output port on the same side are turned on, while the first output port and the second output port on the other side are turned off.

[0011] As a further preferred embodiment of the present invention, when the first output port is on and all four output ports are off, the antenna array operates in state one, with the radiation pattern pointing in the direction of θ≈22°; when the first and second output ports are on and the third and fourth output ports are off, the antenna array operates in state two, with the radiation pattern pointing in the direction of θ≈0°; when the second output port is on and the first, third, and fourth output ports are off, the antenna array operates in state three, with the radiation pattern pointing in the direction of θ≈-22°; when the third output port is on and the first, second, and fourth output ports are off, the antenna array operates in state four, with the radiation pattern pointing in the direction of θ≈158°; when the third and fourth output ports are on and the first and second output ports are off, the antenna array operates in state five, with the radiation pattern pointing in the direction of θ≈180°; and when the fourth output port is on and the first and third output ports are off, the antenna array operates in state six, with the radiation pattern pointing in the direction of θ≈-158°.

[0012] As a further preferred embodiment of the present invention, the matching stub is an open-type matching stub; the open-type matching stub has an opening near the right-angle side of the transmission line and the switchable feed structure.

[0013] As a further preferred embodiment of the present invention, the length of the main transmission line is half the waveguide wavelength; the length of the coupling transmission line is one-quarter the waveguide wavelength.

[0014] The reconfigurable antenna array with a high-gain end-fire beam described in this invention has the following technical advantages compared with existing technologies:

[0015] This invention utilizes a pattern-reconfigurable binary antenna array to provide three high-gain end-fire beams pointing in different directions in both the forward and backward directions, achieving bidirectional high-gain end-fire beam coverage. This effectively ensures high-quality communication in both the forward and backward directions while avoiding electromagnetic interference from other directions, demonstrating good application potential in scenarios such as tunnels, highways, and vehicle environments. Attached Figure Description

[0016] Figure 1 This invention relates to a schematic diagram of a pattern-reconfigurable antenna array with a high-gain end-fire beam.

[0017] Figure 2 This invention relates to a schematic diagram of a switchable feed structure in a pattern reconfigurable antenna array with a high-gain end-fire beam;

[0018] Figure 3 The present invention relates to a horizontal plane radiation pattern of a pattern reconfigurable antenna array with a high-gain end-fire beam under different states at a frequency of 4.9 GHz;

[0019] Figure 4 The present invention relates to a horizontal plane radiation pattern of a pattern reconfigurable antenna array with a high-gain end-fire beam under different states at a frequency of 5.1 GHz;

[0020] Figure 5 The present invention relates to a pattern reconfigurable antenna array with a high-gain end-fire beam, which is shown in the curves of reflection coefficient and main radiation direction gain as a function of frequency under different states.

[0021] In the attached diagram, 1-dielectric substrate, 2-dielectric resonator, 3-metal dipole, 4-transmission line, 5-matching stub, 6-switchable feed structure, 61-main transmission line, 62-coupled transmission line, 63-bent thin line, 64-first pad, 65-ground pad, 66-second pad, 67-thin metal line, 7-rectangular metal ground, 8-input port, 681-first output port, 682-second output port, 683-third output port, 684-fourth output port. Detailed Implementation

[0022] The present invention will be further explained in detail below with reference to the accompanying drawings, so that those skilled in the art can better understand and implement the present invention. However, the following examples are only used to explain the present invention and are not intended to limit the present invention.

[0023] like Figure 1As shown, the present invention proposes a pattern-reconfigurable antenna array with a high-gain end-fire beam, comprising a dielectric substrate 1, a pair of high-gain pattern-reconfigurable end-fire antennas printed on the upper surface of the dielectric substrate 1, a switchable feed structure 6, and a rectangular metal ground 7 printed on the lower surface of the dielectric substrate 1; the vertical projection plane of the switchable feed structure 6 lies on the plane of the rectangular metal ground 7; the pair of high-gain pattern-reconfigurable end-fire antennas are respectively connected to the switchable feed structure 6 and are arranged symmetrically about the vertical center line of the switchable feed structure 6 on the upper surface of the dielectric substrate 1; each of the pair of high-gain pattern-reconfigurable end-fire antennas includes The dielectric resonator 2, metal dipole 3, transmission line 4, and matching stub 5 are arranged symmetrically about the horizontal centerline of the dielectric substrate 1. One end of the transmission line 4 is connected to the metal dipole 3. The other end of the transmission line 4 is connected to the switchable feed structure 6. One side of the transmission line 4 is connected to the matching stub 5. The switchable feed structure 6 has six different operating states from state one to state six. By changing the on / off state of the four PIN diodes embedded in the switchable feed structure 6, six different high-gain end-fire beams can be switched.

[0024] Dielectric resonator 2 is cuboid in shape and operates at TE. 2δ1 The mode, together with the metal dipole 3 located below it, forms a pair of controllable electromagnetic dipoles to obtain a switchable high-gain end-fire beam.

[0025] like Figure 2 As shown, the switchable power supply structure 6 includes a main transmission line 61, four symmetrically arrayed coupling transmission lines 62 on both sides of the main transmission line 61, an input port 8, a first output port 681, a second output port 682, a third output port 683, and a fourth output port 684. One end of the main transmission line 61 is open, and the other end is connected to the input port 8 through a thin metal wire 67. One end of the coupling transmission line 62 is connected to the corresponding first output port 681 to the fourth output port 684 through a bent thin wire 63, and the other end is connected to the first pad 64 through a DC blocking capacitor. The first pad 64 and the ground pad 65 are connected through a PIN diode, with the cathode of the PIN diode connected to the ground pad 65 and the anode connected to the first pad 64. A choke inductor is connected between the first pad 64 and the second pad 66, and a DC power supply is connected to the second pad 66 to control the on / off state of the corresponding PIN diode.

[0026] When a suitable forward bias voltage is applied to the second pad 66 connected to the coupling transmission line 62, the corresponding PIN diode connected to the coupling transmission line 62 is in the conducting state, and the first output port 681 to the fourth output port 684 connected to the coupling transmission line 62 are turned on. When no voltage is applied to the second pad 66 connected to the coupling transmission line 62, the corresponding PIN diode connected to the coupling transmission line 62 is in the off state, and the first output port 681 to the fourth output port 684 connected to the coupling transmission line 62 are turned off. By adjusting the DC voltage applied to the four second pads 66, four states can be achieved: one of the first output ports 681 to the fourth output port 684 is turned on; the first output port 681 and the second output port 682 on the same side are turned on, while the third output port 683 and the fourth output port 684 on the other side are turned off; or the third output port 683 and the fourth output port 684 on the same side are turned on, while the first output port 681 and the second output port 682 on the other side are turned off.

[0027] When the first output port 681 is on and the second to fourth output ports 682 are off, the antenna array operates in state one, with the radiation pattern pointing in the direction of θ≈22°; when the first output port 681 and the second output port 682 are on, and the third output port 683 and the fourth output port 684 are off, the antenna array operates in state two, with the radiation pattern pointing in the direction of θ≈0°; when the second output port 682 is on, and the first, third, and fourth output ports 681, 683, and 684 are off, the antenna array operates in state three, with the radiation pattern pointing in the direction of θ≈-22°; when... When the third output port 683 is on and the first output port 681, the second output port 682, and the fourth output port 684 are off, the antenna array operates in state four, with the radiation pattern pointing in the direction of θ≈158°. When the third output port 683 and the fourth output port 684 are on and the first output port 681 and the second output port 682 are off, the antenna array operates in state five, with the radiation pattern pointing in the direction of θ≈180°. When the fourth output port 684 is on and the first output port 681 to the third output port 683 are off, the antenna array operates in state six, with the radiation pattern pointing in the direction of θ≈-158°.

[0028] Matching stub 5 is an open-type matching stub; the open-type matching stub has an opening near the right-angle side of the transmission line 4 and the switchable feed structure 6. The length of the main transmission line 61 is half the waveguide wavelength; the length of the coupling transmission line 62 is one-quarter the waveguide wavelength.

[0029] The horizontal radiation patterns of a pattern-reconfigurable antenna array with a high-gain end-fire beam under different states according to an embodiment of the present invention are as follows: Figure 3 and Figure 4 As shown. Figure 3 The invention presents horizontal radiation patterns under different conditions at a frequency of 4.9 GHz, according to embodiments of the invention. The peak gain of all six end-firing patterns is greater than 8 dBi, and the front-to-back ratio is greater than 15 dB. Figure 4 The horizontal radiation patterns of the present invention under different conditions at a frequency of 5.1 GHz are shown in the embodiments. The peak gain of the three end-radiated patterns is greater than 8 dBi, and the front-to-back ratio is greater than 15 dB. The embodiments of the present invention show good consistency at different frequency points within the band, and can all guarantee excellent end-radiated performance.

[0030] Figure 5 The curves showing the reflection coefficient and main radiation direction gain as a function of frequency under different states are presented for embodiments of the present invention. The operating bandwidth of the embodiments of the present invention is 12% (4.71–5.31 GHz), and the in-band gain is 7–8.8 dBi.

[0031] This invention utilizes a switchable feed structure 6 to excite a pair of symmetrically arranged high-gain pattern reconfigurable end-fire antennas, and achieves radiation pattern reconstruction by switching the operating state of the feed structure.

[0032] The specific implementation schemes described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific implementation schemes of the present invention and are not intended to limit the scope of the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present invention should fall within the scope of protection of the present invention.

Claims

1. A pattern-reconfigurable antenna array with a high-gain end-fire beam, characterized in that, The device includes a dielectric substrate (1), a pair of high-gain pattern reconfigurable end-fire antennas printed on the upper surface of the dielectric substrate (1), a switchable feed structure (6), and a rectangular metal ground (7) printed on the lower surface of the dielectric substrate (1); the vertical projection plane of the switchable feed structure (6) is on the plane of the rectangular metal ground (7); the pair of high-gain pattern reconfigurable end-fire antennas are respectively connected to the switchable feed structure (6) and are arranged in a symmetrical array about the vertical center line of the switchable feed structure (6) on the upper surface of the dielectric substrate (1); each of the pair of high-gain pattern reconfigurable end-fire antennas includes a dielectric resonator (2), a metal dipole (3), a transmission line (4), and a matching element. Stub (5); the dielectric resonator (2) covers the metal dipole (3); the metal dipole (3), transmission line (4) and matching stub (5) are symmetrically arranged about the horizontal center line of the dielectric substrate (1); one end of the transmission line (4) is connected to the metal dipole (3); the other end of the transmission line (4) is connected to the switchable feed structure (6); one side of the transmission line (4) is connected to the matching stub (5); the switchable feed structure (6) has six different working states from state one to state six, and six different high-gain end-fire beams can be switched by changing the on / off state of the four PIN diodes embedded in the switchable feed structure (6); The switchable power supply structure (6) includes a main transmission line (61), four symmetrically arrayed coupling transmission lines (62) arranged on both sides of the main transmission line (61), an input port (8), a first output port (681), a second output port (682), a third output port (683), and a fourth output port (684); one end of the main transmission line (61) is open-circuited, and the other end is connected to the input port (8) through a thin metal wire (67); one end of the coupling transmission line (62) is connected to the input port (8) through a bent thin wire (63). The first output port (681) is connected to the fourth output port (684), and the other end is connected to the first pad (64) through a DC blocking capacitor. The first pad (64) and the ground pad (65) are connected through a PIN diode. The cathode of the PIN diode is connected to the ground pad (65), and the anode is connected to the first pad (64). A choke inductor is connected between the first pad (64) and the second pad (66). A DC power supply is connected to the second pad (66) to control the on / off state of the corresponding PIN diode. When a suitable positive bias voltage is applied to the second pad (66) connected to the coupling transmission line (62), the corresponding PIN diode connected to the coupling transmission line (62) is in the conducting state, and the first output port (681) to the fourth output port (684) connected to the coupling transmission line (62) are turned on. When no voltage is applied to the second pad (66) connected to the coupling transmission line (62), the corresponding PIN diode connected to the coupling transmission line (62) is in the off state, and the first output port (681) to the fourth output port (684) connected to the coupling transmission line (62) are disconnected. By adjusting the DC voltage applied to the four second pads (66), four states can be achieved: one of the first output ports (681) to the fourth output port (684) is turned on; the first output port (681) and the second output port (682) on the same side are turned on, while the third output port (683) and the fourth output port (684) on the other side are turned off; or the third output port (683) and the fourth output port (684) on the same side are turned on, while the first output port (681) and the second output port (682) on the other side are turned off. When the first output port (681) is turned on and the second output port (682) to the fourth output port (684) are all turned off, the antenna array works in state one, and the radiation pattern points to the direction of θ ≈ 22°. When the first output port (681) and the second output port (682) are connected, and the third output port (683) and the fourth output port (684) are disconnected, the antenna array operates in state two, and the radiation pattern points to the direction of θ ≈ 0°. When the second output port (682) is turned on and the first output port (681), the third output port (683) and the fourth output port (684) are turned off, the antenna array operates in state three, and the radiation pattern points to the direction of θ ≈ -22°. When the third output port (683) is turned on and the first output port (681), the second output port (682) and the fourth output port (684) are turned off, the antenna array operates in state four, at which time the radiation pattern points to the direction of θ ≈ 158°. When the third output port (683) and the fourth output port (684) are connected, and the first output port (681) and the second output port (682) are disconnected, the antenna array operates in state five, at which time the radiation pattern points to the direction of θ ≈ 180°. When the fourth output port (684) is turned on and the first output port (681) to the third output port (683) are turned off, the antenna array operates in state six, and the radiation pattern points to the direction of θ ≈ -158°.

2. The pattern-reconfigurable antenna array with a high-gain end-fire beam according to claim 1, characterized in that, The dielectric resonator (2) is rectangular in shape and operates at TE. 2δ1 The pattern, together with the metal dipole (3) below it, forms a pair of controllable electromagnetic dipoles to obtain a switchable high-gain end-fire beam.

3. The pattern-reconfigurable antenna array with a high-gain end-fire beam according to claim 1, characterized in that, The matching stub (5) is an open-type matching stub; the open-type matching stub is set with an opening near the right-angle side of the transmission line (4) and the switchable feed structure (6).

4. A pattern-reconfigurable antenna array with a high-gain end-fire beam according to claim 1, characterized in that, The length of the main transmission line (61) is half the waveguide wavelength; the length of the coupling transmission line (62) is one-quarter the waveguide wavelength.

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