Reconfigurable phased array antenna

Abstract

The invention provides a reconfigurable phased-array antenna, which comprises a feed substrate, a cavity antenna element and a metal baffle plate, and is characterized in that the feed substrate is provided with an electromagnetic wave input port; the first surface of the cavity antenna element is provided with a feed gap, the feed gap is in contact with the feed substrate, the second surface of the cavity antenna element is provided with a first radiation gap, the electromagnetic wave input port inputs electromagnetic waves, and the first radiation gap emits a first state wave beam after tuning of the feed gap; and the metal baffle is used for covering the first radiation slot, so that the cavity antenna element transmits a second-state wave beam. According to the reconfigurable phased-array antenna, the cavity antenna element is arranged on the feed substrate, the first radiation slot radiates the first-state wave beam, the metal baffle covers the first radiation slot, the cavity antenna element is reconfigured, and the cavity antenna element transmits the second-state wave beam. According to the scheme, beam coverage in a wide space is realized through mechanical reconstruction.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless mobile communications, and in particular to a reconfigurable phased array antenna. Background Art

[0002] Reconfigurable antennas have garnered widespread attention due to their ability to improve system efficiency, enhance communication quality, and meet the needs of diverse scenarios. To achieve wide spatial coverage while ensuring stable communication quality, emerging wireless communication systems are actively exploring the potential of reconfigurable antenna technology. Using electronic control elements to achieve antenna reconfigurability has proven to be an effective approach. For example, Zhang Shuai used a phased array antenna with reconfigurable PIN diode patterns to achieve wide spatial coverage while reducing the number of array elements and transmitting and receiving components, enabling beam scanning from end-fire to side-fire.

[0003] However, these electronically driven reconfigurable antennas often face challenges with high loss, high noise, and complex integration due to the installation of electronic components. Designing antenna arrays with reconfigurable patterns in the millimeter-wave band places higher demands on reconfigurable technology. Traditional mechanical reconfiguration methods are difficult to implement in the millimeter-wave band due to size limitations and machining precision restrictions. Guo Yingjie employed mechanical reconfiguration to achieve antenna polarization reconfiguration in the millimeter-wave band. This antenna utilizes a resonant TM510 mode cavity as its foundation, achieving five different linearly polarized beams through mechanical rotation. This is the only research on millimeter-wave mechanical reconfiguration in the past two years. Achieving stable beam steering in the millimeter-wave band using mechanical reconfiguration methods is challenging. This challenge becomes even more difficult when integrating mechanical reconfiguration with phased array technology. Currently, no literature has proposed using multimode principles to achieve reconfigurable radiation patterns in cavity antenna elements in the millimeter-wave band, particularly for array antennas covering tilted directions. Overall, exploring new reconfigurable methods for stable millimeter-wave beamforming is a meaningful research direction. Summary of the Invention

[0004] Based on the above technical problems, the present invention provides a reconfigurable phased array antenna that realizes beam adjustment through a mechanical structure.

[0005] The present invention provides a reconfigurable phased array antenna, comprising a feed substrate, a cavity antenna element and a metal baffle, wherein the feed substrate is provided with an electromagnetic wave input port; a feed slot is provided on the first surface of the cavity antenna element, and the feed slot is in contact with the feed substrate; a first radiation slot is provided on the second surface of the cavity antenna; the electromagnetic wave input port inputs electromagnetic waves, and after being tuned by the feed slot, a first state beam is emitted by the first radiation slot; the metal baffle is used to cover the first radiation slot, so that the cavity antenna element emits a second state beam.

[0006] Optionally, the cavity antenna element is an all-metal antenna structure, a cube cavity is provided inside the all-metal antenna structure, and the feeding slot and the first radiation slot respectively pass through the all-metal antenna structure.

[0007] Optionally, a second radiation slot is provided on the third surface of the cavity antenna element, and the metal baffle is further used to cover the second radiation slot, so that the cavity antenna element emits a third state beam.

[0008] Optionally, the first surface and the second surface are parallel to each other and perpendicular to the Z-axis direction, and the third surface is perpendicular to the Y-axis direction.

[0009] Optionally, the first surface and the third surface are parallel to each other and perpendicular to the Z-axis direction, and the second surface is perpendicular to the Y-axis direction.

[0010] Optionally, the cavity antenna element includes a plurality of cavity antenna elements, and the plurality of cavity antenna elements are arranged in an array along the X-axis direction on the feeding substrate, and the feeding substrate is provided with a plurality of electromagnetic wave input ports corresponding one-to-one to the cavity antenna elements.

[0011] Optionally, the intersections of the surfaces in the cube cavity are provided with arc chamfers.

[0012] Optionally, the feed substrate includes a dielectric substrate, a front metal covering layer and a back metal covering layer, the front metal covering layer and the back metal covering layer respectively cover the front and back surfaces of the dielectric substrate, the front metal covering layer is provided with a feeding hole, and the feeding hole is used for direct contact between the dielectric substrate and the feeding gap.

[0013] Optionally, the front metal covering layer is further provided with an electromagnetic wave input port mounting hole and a metal through hole, and the metal through hole is arranged outside the mounting hole and the feeding hole.

[0014] Optionally, the metal baffle includes a first metal baffle and a second metal baffle, the first metal baffle can be retracted and arranged outside the second surface, and the second metal baffle can be retracted and arranged outside the third surface.

[0015] Beneficial effects of this program:

[0016] This reconfigurable phased array antenna employs a cavity antenna element mounted on a feed substrate. Electromagnetic waves are fed into the substrate's electromagnetic wave input port, and then fed through a feed slot. The first radiating slot radiates a first-state beam. By placing a metal baffle over the first radiating slot, the cavity antenna element is reconfigured to emit a second-state beam. This mechanical reconfiguration enables wide-area beam coverage, which is crucial for the practical application of millimeter-wave technology and is expected to play a significant role in 5G / 6G base stations. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the structure of a reconfigurable phased array antenna;

[0018] Figure 2 for Figure 1 Front cross-sectional view along AA direction;

[0019] Figure 3 for Figure 1 Side cross-sectional view along the BB direction;

[0020] Figure 4 is a perspective schematic diagram of a cavity antenna element;

[0021] Figure 5 It is a front view of the feed substrate;

[0022] Figure 6 Schematic diagram of the structure of the reconfigurable antenna array state 1;

[0023] Figure 7 Schematic diagram of the test environment for the reconfigurable antenna array state 1;

[0024] Figure 8 Schematic diagram of the return loss of ports 1 and 2 simulated and tested for state 1;

[0025] Figure 9 Schematic diagram of port isolation simulated and tested for state 1;

[0026] Figure 10 Port 1 antenna element pattern simulated and tested for state 1;

[0027] Figure 11 Port 2 antenna element pattern simulated and tested for state 1;

[0028] Figure 12 The antenna beam scanning pattern in state 1;

[0029] Figure 13 Schematic diagram of the test environment for the state reconfigurable antenna array state 2;

[0030] Figure 14Schematic diagram of the return loss of ports 1 and 2 simulated and tested for state 2;

[0031] Figure 15 Schematic diagram of port isolation simulated and tested for state 2;

[0032] Figure 16 Port 1 antenna element pattern simulated and tested for State 2;

[0033] Figure 17 Port 2 antenna element pattern simulated and tested for State 2;

[0034] Figure 18 is the antenna beam scanning pattern in state 2;

[0035] Figure 19 Schematic diagram of the test environment for the state 3 reconfigurable antenna array;

[0036] Figure 20 Schematic diagram of the return loss of ports 1 and 2 simulated and tested for state 3;

[0037] Figure 21 Schematic diagram of port isolation simulated and tested for state 3;

[0038] Figure 22 Port 1 antenna element pattern simulated and tested for state 3;

[0039] Figure 23 Port 2 antenna element pattern simulated and tested for state 3;

[0040] Figure 24 The antenna beam scanning pattern in state 3.

[0041] Description of reference numerals:

[0042] 10. Feed substrate; 11. Dielectric substrate; 12. Front metal covering layer; 13. Back metal covering layer; 14. Feed hole; 15. Electromagnetic wave input port; 16. Mounting hole; 17. Metal through-hole; 20. Cavity antenna element; 21. Feed slot; 22. First radiation slot; 23. Second radiation slot; 24. Cube cavity; 30. Metal baffle; 31. First metal baffle; 32. Second metal baffle. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0044] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", "inside", "outside" and the like, indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the devices or components referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention; the terms "first", "second" and "third" are only used for descriptive purposes and should not be understood as indicating or implying relative importance; in addition, unless otherwise expressly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, an indirect connection through an intermediate medium, or a communication between the internal parts of two components. For those skilled in the art, the specific meanings of the terms in the present invention can be understood according to the specific circumstances.

[0045] See also Figure 1-3 This embodiment discloses a reconfigurable phased array antenna, including a feed substrate 10, a cavity antenna element 20, and a metal baffle 30. The feed substrate 10 is provided with an electromagnetic wave input port 15; a feed slot 21 is provided on the first surface of the cavity antenna element 20, and the feed slot 21 is in contact with the feed substrate 10. A first radiation slot 22 is provided on the second surface of the cavity antenna. Electromagnetic waves are input into the electromagnetic wave input port 15. After being tuned by the feed slot 21, a first state beam is emitted by the first radiation slot 22; the metal baffle 30 is used to cover the first radiation slot 22, so that the cavity antenna element 20 emits a second state beam.

[0046] This reconfigurable phased array antenna employs a cavity antenna element 20 mounted on a feed substrate 10. Electromagnetic waves are fed into the feed substrate 10's electromagnetic wave input port 15, and then fed through a feed slot 21. A first radiating slot 22 radiates a first-state beam. By covering the first radiating slot 22 with a metal baffle 30, the cavity antenna element 20 is reconfigured to emit a second-state beam. This mechanical reconfiguration achieves wide spatial beam coverage, which is crucial for the practical application of millimeter-wave technology and is expected to play a significant role in 5G / 6G base stations.

[0047] See also Figure 4The cavity antenna element 20 is an all-metal antenna structure. A cube cavity 24 is provided inside the all-metal antenna structure. The feeding slot 21 and the first radiation slot 22 respectively pass through the all-metal antenna structure. A second radiation slot 23 is provided on the third surface of the cavity antenna element 20. The metal baffle 30 is also used to cover the second radiation slot 23, so that the cavity antenna element 20 emits a third state beam. The intersection of the surfaces in the cube cavity 24 is provided with an arc chamfer to adapt to millimeter wave CNC machine tool (CNC) processing. This is an all-metal antenna structure that uses slots for feeding and radiation. The slots distributed on different surfaces play the role of feeding and radiation respectively.

[0048] In this embodiment, the metal baffle 30 includes a first metal baffle 31 and a second metal baffle 32 . The first metal baffle 31 can be retracted outside the second surface, and the second metal baffle 32 can be retracted outside the third surface.

[0049] In this embodiment, the first surface and the second surface are parallel to each other and perpendicular to the Z axis, and the third surface is perpendicular to the Y axis. Of course, the first surface and the third surface can also be parallel to each other and perpendicular to the Z axis, and the second surface can be perpendicular to the Y axis.

[0050] In this embodiment, the cavity antenna elements 20 include four. The four cavity antenna elements 20 are arranged in an array along the X-axis direction on the feed substrate 10. The feed substrate 10 is provided with four electromagnetic wave input ports 15 corresponding to the cavity antenna elements 20 one by one.

[0051] See also Figure 5 The feed substrate 10 includes a dielectric substrate 11, a front metal covering layer 12, and a back metal covering layer 13. The front metal covering layer 12 and the back metal covering layer 13 cover the front and back surfaces of the dielectric substrate 11, respectively. The front metal covering layer 12 is provided with a feed hole 14, which is used to directly contact the dielectric substrate 11 and the feed slot 21. The front metal covering layer 12 also has a mounting hole 16 for mounting the electromagnetic wave input port 15 and a metal through-hole 17. The metal through-hole 17 is arranged outside the mounting hole 16 and the feed hole 14.

[0052] The substrate is made of Rogers 5880 with a thickness of 0.787 mm. The structure of the antenna feed substrate 10 is as follows Figure 3 The yellow area represents the metal cover, while the red area represents the metal through-hole 17. The white portion r2 is a screw, a common through-hole that secures the substrate and antenna structure. The back of the substrate is also covered with a metal cover.

[0053] See also Figure 1, showing a model of a reconfigurable three-state phased antenna array. Four reconfigurable cavity antenna elements 20 are located along the X-axis. Furthermore, metal baffles 30 can be optionally provided on the second and third surfaces. Mini-SMP connectors are used for feeder connections, which are then connected to a vector network analyzer. The antenna is fed via a substrate-integrated waveguide, with a slot at the bottom of the cavity connecting to the substrate-integrated waveguide. Four electromagnetic wave input ports 15 are arranged sequentially along the Z-axis.

[0054] Reconfigurable Antenna Array Testing and Analysis

[0055] Reconfigurable antenna array state 1

[0056] The antenna is processed using CNC machine tool technology. Figure 6 The structural diagram of the reconfigurable three-state phased antenna array state 1 is shown. Figure 6 In the simulated antenna structure, a metal wall placed perpendicular to the Y-axis blocks the cavity's radiation slot. Meanwhile, the radiation slot perpendicular to the Z-axis remains unobstructed. The arrows indicate the coverage of the phased array beam. By adjusting the phase difference between ports 1 and 4, beam scanning in the broadside direction is achieved. Figure 7 The test environment is shown in Figure 1. The BBOX can provide different beam amplitudes and phases for each antenna port and is connected to the antenna via four RF coaxial cables. In actual testing, absorbing materials are used to shield the BBOX to minimize its impact on antenna testing.

[0057] The antenna S parameters simulated and tested in state 1 are as follows Figure 8 and Figure 9 As shown, ports 1 and 4 are symmetrical to each other, and ports 2 and 3 are symmetrical to each other, so only the S parameters of ports 1 and 2 are shown. Figure 8 is the return loss of port 1 and port 2, indicating that the return loss of the two ports of the antenna is less than -10dB at 27.91GHz, meeting the radiation requirements. Figure 9 As shown, the simulated and measured return loss between adjacent ports is less than -20 dB at 27.91 GHz, demonstrating high isolation between adjacent ports. Simulated and measured results within the band are generally consistent. Errors in test cables and manual soldering can lead to ripples. Using more precise processing, high-quality cables, and integrated soldering can reduce test fluctuations.

[0058] Figure 10-11 The simulated and measured antenna element patterns for State 1 are shown. When testing a single port, the remaining ports were connected to 50Ω loads. The peak gains for Port 1 and Port 2 were 6.7dBi and 7.1dBi, respectively. The simulated and measured antenna patterns are essentially identical.

[0059] State 1 antenna beam scanning pattern is as follows Figure 12 As shown, when the beam is scanned to 0°, 10°, 20°, and 25°, the peak gain of the antenna radiation pattern is 12.9dBi, 12.2dBi, 10.9dBi, and 10.3dBi, respectively. The test results are generally consistent with the simulation results, with the measured results being approximately 1.5dBi lower than the simulation results. Millimeter-wave transmission and welding cause insertion loss, which leads to a reduction in gain. This 1.5dBi is within the normal error range.

[0060] Reconfigurable antenna array state 2

[0061] Figure 13 The reconfigurable three-state phased antenna array state 2 is demonstrated. Figure 13 In the figure, the metal covering wall blocks the cavity gap along the Z-axis, so that the antenna radiates toward the Y-axis. When different phase differences are provided for the four ports, the arrows in the figure indicate the scanning direction of the beam.

[0062] The antenna S parameters simulated and tested in state 2 are as follows Figure 14 As shown in the figure, the ports are symmetrical, so only port 1 and port 2 are tested. The simulated and measured return losses of port 1 and port 2 at 27.91 GHz are both lower than -10 dB. Figure 15 As shown in Figure 1, at 27.91 GHz, both the simulated and measured return loss between adjacent ports is less than -20 dB. This demonstrates high isolation between adjacent ports. Similarly, fluctuations in return loss during testing are due to the effects of the RF cable and hand-soldered parts.

[0063] The antenna array element pattern of state 2 simulation and test is as follows Figure 16-17 As shown, during single-port testing, the remaining ports are connected to 50Ω loads. Figure 16 is the antenna pattern when accessing port 1, Figure 17 This is the antenna pattern when accessing port 2. The peak gains at ports 1 and 2 are 7.2dBi and 8.7dBi, respectively, and the cross-polarization remains below -10dBi. The simulated and measured far-field radiation patterns of the array elements are essentially consistent.

[0064] The antenna beam scanning pattern in state 2 is as follows Figure 18 As shown in Figure 1, the radiation patterns at scan angles of 0°, 10°, 20°, and 25° exhibit peak gains of 14.13dBi, 13.3dBi, 11dBi, and 9.84dBi, respectively. The test results agree well with the simulation data, with an error of less than 1dBi.

[0065] Reconfigurable antenna array state 3

[0066] Figure 19The reconfigurable three-state phased antenna array state 3 is demonstrated. Figure 19 This simulation model is for State 3. In State 3, there is no influence of the metal-covered wall, so the beams in two directions are superimposed to produce a tilted beam. When the ports have different phase differences, the antenna can achieve the beam coverage indicated by the arrow in the figure.

[0067] The antenna S parameters simulated and tested in state 3 are as follows Figure 20-21 As shown, Figure 20 The reflection coefficients of state 3 at ports 1 and 2 are both lower than -10dB at 27.91GHz. Figure 21 The simulated and measured isolation between adjacent ports is less than -20dB.

[0068] Figure 22-23 The antenna element pattern for State 3 simulation and testing is shown. Figure 22 The peak gain of port 1 is 8.5dBi. Figure 23 The peak gain of port 2 is 9.2dBi. Tests show that the cross-polarization levels in both simulation and test are lower than -10dB, confirming the feasibility of the proposed model.

[0069] Use BBOX to test beam scanning capability. Figure 24 The antenna beam scanning pattern for State 3 is shown. The radiation patterns at scanning angles of 0°, 10°, 20°, and 25° correspond to maximum gains of 14.9dBi, 14.5dBi, 13.4dBi, and 12.4dBi, respectively. Due to the antenna's symmetrical structure, only one side of the beam scanning range is shown. It's worth noting that the antenna operates in the same frequency band in all three states.

[0070] This proposal pioneered a new method for reconfiguring millimeter-wave beam directions using metal-clad walls. This innovative approach lays the foundation for designing a reconfigurable cavity antenna capable of multi-mode resonance. The proposed structure achieves three unique beam forms: sidefire, oblique, and endfire, by tuning different states at the same frequency. Using this approach, a 1×4 reconfigurable phased array antenna operating in the millimeter-wave band was designed. Furthermore, the reconfigurable antenna array achieved a 50° beam scanning range with a gain greater than 9dBi. This design, which combines the capabilities of a phased array and a three-state mechanically reconfigurable array, is expected to play an important role in future 5G / 6G base stations.

[0071] The above embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A reconfigurable phased array antenna, characterized in that: include: A feeding substrate, wherein an electromagnetic wave input port is provided on the feeding substrate; A cavity antenna element, wherein a feeding slot is provided on a first surface of the cavity antenna element, the feeding slot is in contact with the feeding substrate, a first radiating slot is provided on a second surface of the cavity antenna, an electromagnetic wave is input to the electromagnetic wave input port, and after being tuned by the feeding slot, a first state beam is emitted from the first radiating slot; A metal baffle is used to cover the first radiation slot, so that the cavity antenna element emits a second state beam.

2. The reconfigurable phased array antenna according to claim 1, wherein: The cavity antenna element is an all-metal antenna structure, a cube cavity is provided inside the all-metal antenna structure, and the feeding slot and the first radiation slot are respectively provided through the all-metal antenna structure.

3. The reconfigurable phased array antenna according to claim 2, wherein: A second radiation slot is provided on the third surface of the cavity antenna element, and the metal baffle is further used to cover the second radiation slot, so that the cavity antenna element emits a third state beam.

4. The reconfigurable phased array antenna according to claim 3, characterized in that: The first surface and the second surface are parallel to each other and perpendicular to the Z-axis direction, and the third surface is perpendicular to the Y-axis direction.

5. The reconfigurable phased array antenna according to claim 3, wherein: The first surface and the third surface are parallel to each other and perpendicular to the Z-axis direction, and the second surface is perpendicular to the Y-axis direction.

6. The reconfigurable phased array antenna according to claim 2, wherein: The cavity antenna elements include a plurality of cavity antenna elements, which are arranged in an array along the X-axis direction on the feed substrate. The feed substrate is provided with a plurality of electromagnetic wave input ports corresponding one-to-one to the cavity antenna elements.

7. The reconfigurable phased array antenna according to claim 2, wherein: The intersections of the surfaces in the cube cavity are provided with arc chamfers.

8. The reconfigurable phased array antenna according to claim 1, wherein: The feed substrate includes a dielectric substrate, a front metal covering layer and a back metal covering layer, wherein the front metal covering layer and the back metal covering layer respectively cover the front and back surfaces of the dielectric substrate, and the front metal covering layer is provided with a feed hole, which is used for direct contact between the dielectric substrate and the feed gap.

9. The reconfigurable phased array antenna according to claim 8, characterized in that: The front metal covering layer is further provided with an electromagnetic wave input port mounting hole and a metal through hole, and the metal through hole is arranged outside the mounting hole and the feeding hole.

10. The reconfigurable phased array antenna according to claim 3, wherein: The metal baffle includes a first metal baffle and a second metal baffle. The first metal baffle can be retracted and arranged outside the second surface, and the second metal baffle can be retracted and arranged outside the third surface.

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