Reconfigurable Transmissive-Reflective Array Antenna for Non-Line-of-Sight Microwave Propagation

Abstract

This invention relates to the field of antenna technology and discloses a reconfigurable transmissive-reflective array antenna for non-line-of-sight microwave propagation. The antenna includes a control circuit and sequentially arranged components: a first polarization grating layer, a first dielectric layer, M×N resonant plates, a second dielectric layer, and a second polarization grating layer. Each resonant plate includes a radiating portion, a ground wire, four extensions, and two PIN diodes. The four extensions are symmetrically arranged around the radiating portion and connected to it. The two PIN diodes are respectively located on two adjacent extensions and connected to the upper and lower polarization grating layers via curved lines on the extensions and metal pillars in the dielectric layer. One end of the ground wire is connected to the radiating portion, and the other end is connected to DC ground. The control circuit controls the conduction and disconnection of the PIN diodes through the polarization grating layers to achieve either a transmission mode or a reflection mode. This reconfigurable transmissive-reflective array antenna for non-line-of-sight microwave propagation has a relatively simple structure and can reduce losses.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and more specifically, to a reconfigurable transflective array antenna for non-line-of-sight microwave propagation. Background Technology

[0002] In wireless communication, a direct, straight-line propagation path cannot be established between the transmitter and receiver due to obstacles (such as buildings, trees, terrain, etc.). This situation is called non-line-of-sight microwave propagation. In non-line-of-sight propagation, wireless signals mainly reach the receiver through multipath propagation methods such as reflection, scattering, and diffraction. This can cause polarization mismatch, reduced signal strength, and multipath effects.

[0003] PIN diode reconfigurable transflective array antennas are a technology that dynamically adjusts antenna performance by controlling the on and off states of PIN diodes. PIN diode reconfigurable transflective array antennas offer advantages such as wide coverage, high gain, and dynamic beamforming. They can achieve multi-area, long-distance coverage and adjust beam shape according to scenario requirements, improving connection flexibility and reducing path interference. This meets the demanding and urgent needs of non-line-of-sight microwave propagation communication systems, thus possessing high research and application value.

[0004] To achieve good reconfiguration performance, traditional reconfigurable transflective array antennas require complex control circuits to dynamically adjust the PIN diodes, which increases the complexity of the structure and losses.

[0005] Furthermore, in traditional PIN diode reconfigurable transflective array antennas, to achieve grounding and reduce the impact of the grounding wire on the radiating elements, each radiating element in the same row or column uses only the same grounding wire, with one end of the grounding wire connected to DC ground. This structure can reduce the area occupied by the grounding wire in the radiating elements both vertically and horizontally, allowing the radiating elements to maintain good radiation efficiency. However, if a radiating element in the same row or column experiences a transmission failure or a grounding wire failure between adjacent radiating elements, the radiating elements in that row or column will be unable to achieve grounding functionality. Summary of the Invention

[0006] This invention is made to solve the above-mentioned technical problems. One of its objectives is to provide a reconfigurable transflective array antenna for non-line-of-sight microwave propagation, which has a relatively simple structure, can reduce losses, and has good radiation efficiency.

[0007] According to one embodiment of the present invention, a reconfigurable transflective array antenna for non-line-of-sight microwave propagation is provided, comprising a control circuit and sequentially arranged first polarization gate layer, first dielectric layer, M×N resonators, second dielectric layer, and second polarization gate layer, where M and N are natural numbers not less than 1, and M×N is not less than 2; each resonator includes a radiating portion, four grounding wires, four extensions, and two PIN diodes, the four extensions being symmetrically arranged around the radiating portion and connected to the radiating portion, each extension including a first branch and two symmetrical second branches, one end of the first branch being connected to the radiating portion and the other end being connected to one end of the second branch, the other end of the second branch forming a bent structure; two PIN diodes are respectively disposed on two adjacent first branches, one PIN diode being connected to the first polarization gate layer via a bent line on the second branch and a metal pillar in the first dielectric layer, the other... The PIN diodes are connected to the second polarized gate layer via a curved line on the second branch and a metal pillar in the second dielectric layer. Four grounding lines are symmetrically arranged around the outer periphery of the radiating portion and spaced apart from the extension portion. The grounding lines of the horizontally and vertically adjacent resonant plates are all connected together, connecting each radiating portion to DC ground. The first polarized gate layer consists of several first metal strips, and the second polarized gate layer consists of several second metal strips orthogonal to the first metal strips. The metal strips are connected to the control circuit, and the anodes of different PIN diodes are connected to different metal strips. The control circuit controls the conduction and disconnection of the PIN diodes. When any PIN diode in the resonant plate is turned on by the control circuit, the resonant plate transmits a signal of a preset frequency. When two PIN diodes in the resonant plate are turned on or off simultaneously by the control circuit, the resonant plate reflects a signal of a preset frequency.

[0008] As one implementation, the curved line is positioned at the location where the electric field of the resonator is weakest.

[0009] In one embodiment, the first dielectric layer has a receiving groove opposite to the PIN diode, and the main body of the PIN diode is disposed in the receiving groove.

[0010] In one implementation, the conduction and disconnection of the two PIN diodes include four states: state "00", both PIN diodes are off; state "01", the first PIN diode is off and the second PIN diode is on; state "10", the first PIN diode is on and the second PIN diode is off; state "11", both PIN diodes are on; wherein, in states "01" and "10", the signal transmitted by the resonator has a phase difference of 180°; and in states "00" and "11", the signal reflected by the resonator has a phase difference of 180° ± 20°.

[0011] As one implementation, in the antenna radiation preset direction When the beam is in the desired direction, the phase compensation required for each of the resonators to generate for the fed electromagnetic wave is: , , , The wavelength of the electromagnetic wave radiated by the antenna; the state of the two PIN diodes in each of the resonators in transmission mode. for:

[0012] ;

[0013] In reflection mode, the state of the two PIN diodes in each of the resonant plates for:

[0014] ;

[0015] In the formula, and These are the position vectors of the antenna feed and the resonator, respectively. This represents the optimized value for a one-dimensional spatially fed planar array.

[0016] In one embodiment, 16×16 resonant plates are provided between the first dielectric layer and the second dielectric layer.

[0017] In one embodiment, both the first dielectric layer and the second dielectric layer are F4-B substrates with a thickness of 1.8 mm, a dielectric constant of 2.65, and a loss tangent of 0.001.

[0018] In one implementation, the control circuit is an FPGA controller; the metal strip is connected to the control circuit via pin headers connected to DuPont wires.

[0019] In one embodiment, the center of the radiating portion has several hollow structures.

[0020] Based on the above description and practical application, it is clear that in the reconfigurable transflective array antenna for non-line-of-sight microwave propagation, the orthogonally arranged first and second polarization gate layers simultaneously serve as polarization conversion layers and DC bias line layers. PIN diodes are connected to the polarization gate layers via bent lines and metal pillars, and then connected to the control circuit. The two polarization gate layers directly replace the traditional DC bias line layer, simplifying the antenna structure, reducing the antenna's profile height and manufacturing cost, while eliminating the blocking effect of dense DC bias lines in traditional antennas of this type, improving the antenna's transmission / reflection coefficient, thereby increasing the antenna's radiation efficiency and reducing antenna losses.

[0021] Each radiating element is connected horizontally and vertically via grounding wires, providing a stable grounding effect. Simultaneously, each resonator has four extensions located between the four grounding wires. Each extension includes a first branch and a second branch, with the second branch having a bent structure at its end. This extension structure itself compensates for the impact of the grounding wires on radiation efficiency. Compared to traditional array antennas where only radiating elements in the same row or column are connected by grounding wires, in this invention, each row and column of resonators is connected by grounding wires, resulting in not only a stable grounding effect but also maintaining good radiation efficiency.

[0022] The reconfigurable transmissive-reflective array antenna of the present invention, applied to non-line-of-sight microwave propagation, can transmit and reflect signals of a preset frequency by controlling the on / off state of two PIN diodes in each resonator. Furthermore, in both transmission and reflection modes, the radiated signals have a phase difference of approximately 180°, enabling beam scanning. Symmetrical beam scanning is also achieved through four extensions symmetrically arranged around the outer periphery of the radiating section. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a resonator and its connected components in a reconfigurable transflective array antenna for non-line-of-sight microwave propagation, according to one embodiment of the present invention, wherein the structure is in a decomposed state.

[0024] Figure 2 This is a schematic diagram of the structure of the first polarization grating layer in a reconfigurable transflective array antenna for non-line-of-sight microwave propagation, according to one embodiment of the present invention.

[0025] Figure 3 This is a schematic diagram of the resonator in a reconfigurable transflective array antenna for non-line-of-sight microwave propagation, according to one embodiment of the present invention.

[0026] Figure 4 This is a schematic diagram of the structure of the second polarization grating layer in a reconfigurable transflective array antenna for non-line-of-sight microwave propagation, according to one embodiment of the present invention.

[0027] Figure 5 This is a schematic diagram of 16×16 resonators and their partially enlarged structure in a reconfigurable transflective array antenna for non-line-of-sight microwave propagation, as described in one embodiment of the present invention.

[0028] Figure 6 This is a schematic diagram of the first polarization grating layer and its partially enlarged structure in a reconfigurable transflective array antenna for non-line-of-sight microwave propagation, according to one embodiment of the present invention.

[0029] Figure 7 This is a schematic diagram of the operation of a reconfigurable transflective array antenna for non-line-of-sight microwave propagation according to one embodiment of the present invention.

[0030] Figures 8a to 8g This is a phase compensation diagram of a reconfigurable transmissive-reflective array antenna for non-line-of-sight microwave propagation in both transmission and reflection modes, according to one embodiment of the present invention. Figure 8a This indicates that the deflection angle of the beam radiated by the antenna is 0°. Figure 8b This indicates that the deflection angle of the beam radiated by the antenna is 10°. Figure 8c This indicates that the deflection angle of the beam radiated by the antenna is 20°. Figure 8d This indicates that the deflection angle of the beam radiated by the antenna is 30°. Figure 8e This indicates that the deflection angle of the beam radiated by the antenna is 40°. Figure 8f This indicates that the deflection angle of the beam radiated by the antenna is 50°. Figure 8g This indicates that the deflection angle of the antenna's radiated beam is 60°. The yellow area in the diagram represents the phase compensation value required by the resonator at that location. In the diagram, blue indicates the phase compensation value required for the resonator at that location. .

[0031] Figure 9a and Figure 9b This is a performance diagram of a reconfigurable transflective array antenna for non-line-of-sight microwave propagation in transmission mode, according to one embodiment of the present invention.

[0032] Figure 10a and Figure 10b This is a performance diagram of a reconfigurable transflective array antenna for non-line-of-sight microwave propagation in reflection mode, according to one embodiment of the present invention.

[0033] Figure 11 This is a radiation pattern in transmission mode of a reconfigurable transflective array antenna for non-line-of-sight microwave propagation, as described in one embodiment of the present invention.

[0034] Figure 12This invention relates to the gain and aperture efficiency of a reconfigurable transflective array antenna for non-line-of-sight microwave propagation in transmission mode, as described in one embodiment of the invention.

[0035] Figure 13a and Figure 13b This is a beam scan pattern at 10° intervals in transmission mode for a reconfigurable transmissive-reflective array antenna used for non-line-of-sight microwave propagation, according to one embodiment of the present invention. Figure 13a For XOZ side, Figure 13b It is a YOZ side.

[0036] Figure 14 This is a radiation pattern of a reconfigurable transflective array antenna for non-line-of-sight microwave propagation in reflection mode, as described in one embodiment of the present invention.

[0037] Figure 15 This invention relates to the gain and aperture efficiency of a reconfigurable transflective array antenna for non-line-of-sight microwave propagation in reflection mode, as described in one embodiment of the invention.

[0038] Figure 16a and Figure 16b This is a beam scan pattern at 10° intervals in reflection mode for a reconfigurable transflective array antenna used for non-line-of-sight microwave propagation, according to one embodiment of the present invention. Figure 16a For XOZ side, Figure 16b It is a YOZ side. Detailed Implementation

[0039] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be more comprehensive and complete, and will fully convey the concept of exemplary embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0040] Furthermore, the accompanying drawings are merely illustrative of this disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted. It should be noted that in this disclosure, the terms "comprising," "configured with," and "set in" are used to indicate an open-ended inclusion, meaning that additional elements / components / etc. may exist besides those listed; the terms "first," "second," etc., are used only as labels and are not intended to limit the number or order of objects; the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention.

[0041] Unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0042] According to one embodiment of the present invention, a reconfigurable transflective array antenna for non-line-of-sight microwave propagation is provided. Please refer to [reference needed]. Figures 1 to 7 The reconfigurable transflective array antenna for non-line-of-sight microwave propagation includes a control circuit and sequentially arranged components: a first polarization grating layer 1, a first dielectric layer 2, M×N resonators 3, a second dielectric layer 4, and a second polarization grating layer 5. M and N are natural numbers not less than 1, and M×N is not less than 2. M and N represent the number of rows and columns in the array antenna; the larger the values ​​of M and N, the better the antenna performance.

[0043] Figure 1 The structure of a resonant plate 3 and its upper and lower connected components is shown. The resonant plate 3 includes a radiating portion 31, four ground wires 32, four extension portions 33, and two PIN diodes 34. The four extension portions 33 are symmetrically arranged on the outer periphery of the radiating portion 31 and connected to the radiating portion 31. The two PIN diodes 34 are respectively disposed on two adjacent extension portions 33. One PIN diode 34 is connected to the first polarized gate layer 1 via a bent line 35 on the extension portion 33 and a metal pillar 36 in the first dielectric layer 2. The other PIN diode 34 is connected to the second polarized gate layer 5 via a bent line 35 on the extension portion 33 and a metal pillar 36 in the second dielectric layer 4.

[0044] Four grounding wires 32 are symmetrically arranged around the outer periphery of the radiating part 31 and spaced apart from the extension part 33. The grounding wires 32 of the horizontally and vertically adjacent resonant plates 3 are all connected together, and the grounding wires 32 connect each radiating part 31 to the DC ground. Figure 5 As shown, the grounding wires 32 of adjacent resonators 3 are connected together, and finally, by setting a lead on one side of multiple resonators 3, all resonators 3 can be connected to DC ground.

[0045] The first polarized gate layer 1 consists of several first metal strips, and the second polarized gate layer 5 consists of several second metal strips orthogonal to the first metal strips. The metal strips are connected to the control circuit, and the anodes of different PIN diodes 34 are connected to different metal strips. The control circuit controls the on / off state of each PIN diode 34; in other words, the control circuit can independently control the on / off state of each PIN diode 34 through the several metal strips. Specifically, when the control circuit controls any one PIN diode 34 in the resonant plate 3 to be on, the resonant plate 3 transmits a signal of a preset frequency; when the control circuit controls two PIN diodes 34 in the resonant plate 3 to be on or off simultaneously, the resonant plate 3 reflects a signal of a preset frequency.

[0046] In this embodiment, the extension 33 includes a first branch 331 and two symmetrical second branches 332. For example... Figure 3 As shown, one end of the first branch 331 is connected to the radiating part 31, and the other end is connected to one end of the second branch 332. The other end of the second branch 332 has a bent structure. The PIN diode 34 is disposed on the first branch 331, and one end of the bent line 35 is connected to the second branch 332. This structural form of the extension 33 increases the current path, widens the antenna bandwidth, and improves the antenna's radiation efficiency. It can cooperate with the radiating part 31 to achieve a higher transmission coefficient and reflection coefficient, further improving the antenna's radiation efficiency.

[0047] In this reconfigurable transflective array antenna for non-line-of-sight microwave propagation, the orthogonally arranged first polarization grating layer 1 and second polarization grating layer 5 simultaneously serve as the polarization conversion layer and DC bias line layer. PIN diodes 34 are connected to the polarization grating layers via bent lines 35 and metal pillars 36, and then connected to the control circuit. The two polarization grating layers directly replace the traditional DC bias line layer, simplifying the antenna structure, reducing the antenna's profile height and manufacturing cost, while eliminating the blocking effect of dense DC bias lines in traditional antennas of this type. This improves the antenna's transmission / reflection coefficient, thereby increasing the antenna's radiation efficiency and reducing antenna losses.

[0048] The reconfigurable transmissive-reflective array antenna of the present invention, applied to non-line-of-sight microwave propagation, can transmit and reflect signals of a preset frequency by controlling the on / off state of the two PIN diodes 34 in each resonator 3. Furthermore, in both transmission and reflection modes, the radiated signals have a phase difference of approximately 180°, enabling beam scanning. Symmetrical beam scanning is also achieved through four extensions 33 symmetrically arranged around the outer periphery of the radiating section 31.

[0049] It should be noted that, in this embodiment, the resonant plates 3 in each row and each column are connected together by grounding wires 32, and the grounding wires 32 in a single resonant plate 3 are arranged in a specific pattern. Figure 3 The cross shape is shown. In actual use, even if a single resonator 3 fails, or the grounding wire 32 between any two resonators 3 fails, this series-parallel connection method can ensure that each resonator 3 in the array is grounded. Undoubtedly, the increased number of grounding wires 32 will occupy the area of ​​the resonator 3 used for radiation. Therefore, in this embodiment, an extension 33 is provided between each of the four grounding wires 32. Each resonator 3 includes four extensions 33, and by means of the arrow-shaped structure of the extensions 33 themselves, and the curved structure at the end, the area of ​​the radiation-bearing part can be expanded without increasing the area of ​​the dielectric substrate. In this embodiment, the radiation-bearing part mainly consists of the radiating part 31 and the extensions 33; in other embodiments without extensions 33, the radiation-bearing part mainly consists of the radiating part 31.

[0050] by Figure 3 and Figure 5 For example, in a traditional array antenna, only the vertical resonators 3 are connected together by grounding wires 32, while no grounding wires 32 are placed between horizontally adjacent resonators 3. Therefore, a radiating part 31 or an extension part 33 (the part that undertakes the radiation function) can be placed at this position, so that the antenna has better radiation efficiency. However, if grounding wires 32 are placed between horizontally adjacent resonators 3, it will occupy the area of ​​the part that undertakes the radiation function at that position, reducing the radiation efficiency of the antenna.

[0051] In other words, in the prior art, adding a grounding wire 32 to achieve stable grounding function and maintaining good radiation efficiency of the antenna are contradictory. In this embodiment, in order to solve this technical problem, while adding a grounding wire 32, the structure and number of extensions 33 are also improved. The two work together to solve the technical problem, so that the array antenna can achieve stable grounding function while maintaining good radiation efficiency.

[0052] As one implementation, the bent line 35 is positioned at the weakest point of the electric field in the resonant plate 3, which reduces the impact on the radio frequency signal. In this antenna, the bent line 35 connects the polarization gate layer and the diode, and also blocks the radio frequency signal to be transmitted by the antenna and the DC signal from the control circuit controlling the PIN diode 34. Furthermore, the bent line 35 can be configured as a high-impedance line and have a reduced width to improve the aforementioned blocking effect.

[0053] In one embodiment, the first dielectric layer 2 has a receiving groove opposite to the PIN diode 34, the main body of the PIN diode 34 is disposed in the receiving groove, and the diode's pins are connected to the first branch. This structure can further reduce the antenna's profile height and make the connection between the components of each layer more compact and robust.

[0054] As one implementation, the radiating section 31 has several hollow structures in its middle, which can reduce the capacitive load on high-frequency signals, reduce parasitic capacitance, expand bandwidth, and improve the antenna's heat dissipation performance. The reduced area of ​​the radiating section can be compensated by the extension section 33 and the bending structure at its end, without reducing radiation efficiency. On the contrary, it can further improve radiation efficiency by improving heat dissipation performance.

[0055] In this embodiment, the conduction and disconnection of the two PIN diodes 34 in each resonant chip 3 includes four states: state "00", state "01", state "10", and state "11". State "00" indicates that both PIN diodes 34 are off; state "01" indicates that the first PIN diode 34 is off and the second PIN diode 34 is on; state "10" indicates that the first PIN diode 34 is on and the second PIN diode 34 is off; and state "11" indicates that both PIN diodes 34 are on. In states "01" and "10", the signal transmitted by the resonant chip 3 has… The phase difference; in states “00” and “11”, the signal reflected by resonator 3 has a phase difference of 180°±20°.

[0056] This reconfigurable transflective array antenna for non-line-of-sight microwave propagation achieves amplitude and phase control for two modes using only the states of two diodes. Compared to most similar antennas currently available, where two diodes can only control two states of one mode, this invention significantly improves component utilization and reduces antenna cost.

[0057] In this embodiment, the reconfigurable transflective array antenna for non-line-of-sight microwave propagation radiates in a predetermined direction. When the beam is in the desired direction, the phase compensation required for each of the 3 pairs of fed electromagnetic waves from each resonator is: , , , The wavelength of the electromagnetic wave radiated by the antenna.

[0058] In transmission mode, in order to generate the corresponding phase compensation, the states of the two PIN diodes 34 in each resonator 3 are... for: That is, when each resonator 3 needs to generate a phase shift value in the range of [-90°, 90°], the first PIN diode 34 should be in the on state and the second PIN diode 34 should be in the off state; when each resonator 3 needs to generate a phase shift value in the range of less than -90° or greater than 90°, the first PIN diode 34 should be in the off state and the second PIN diode 34 should be in the on state.

[0059] In reflection mode, in order to generate the corresponding phase compensation, the states of the two PIN diodes 34 in each resonator 3 are... for: That is, when each resonator 3 needs to generate a phase shift value in the range of [-90°, 90°], both PIN diodes 34 should be in the off state at the same time; when each resonator 3 needs to generate a phase shift value in the range of less than -90° or greater than 90°, both PIN diodes 34 should be in the on state at the same time.

[0060] In the above formula, and These are the position vectors of the antenna feed and the resonator 3, respectively. The optimized values ​​for a one-dimensional spatially fed planar array can be obtained through co-simulation using HFSS and Matlab, and can be applied to different... The phase distribution is simulated and optimized to select the value at which the gain is optimal.

[0061] In one specific embodiment, 16×16 resonant plates 3 are disposed between the first dielectric layer 2 and the second dielectric layer 4. The control circuit is an FPGA controller, and each metal strip in the first polarization gate layer 1 and the second polarization gate layer 5 is connected to the control circuit via pin headers connected to DuPont wires. Both the first dielectric layer 2 and the second dielectric layer 4 are F4-B substrates with a thickness of 1.8 mm, a dielectric constant of 2.65, and a loss tangent of 0.001. The first polarization gate layer 1 is disposed on the upper surface of the first dielectric layer 2, and the second polarization gate layer 5, orthogonal to the first polarization gate layer 1, is disposed on the lower surface of the second dielectric layer 4. The two polarization gate layers simultaneously serve as polarization conversion layers and DC bias line layers. The resonant plate 3 is composed of a square radiating portion 31 and a bent extension portion 33, wherein a PIN diode 34 is embedded in the extension portion 33, and a hole is opened in the first dielectric layer 2 to form a reserved space for the diode. The PIN diode 34, model MACOMMADP-000907-14020, can be represented as a lumped resistor-inductor-capacitor (RLC) element in different states: In the on-state, the resistance R = 7.8Ω, the inductance L = 30pH, the bias voltage is 1.34V, and the current is 10mA; in the off-state, the capacitance C = 25fF, and the inductance L = 30pH. To independently control the DC bias voltage applied to the PIN diode 34, a bent line 35 is used as a blocking component to isolate RF and DC signals. The bent line 35 is placed at the weakest position of the electric field on the resonant plate 3. The bent line 35 is connected to the back-end FPGA control circuit through the metal pillar 36 and the polarized gate layer, reducing the impact of the bias line on the antenna transmission characteristics.

[0062] The effective size of the array antenna is 240×240mm. 2 Each resonator 3 is controlled by 512 PIN diodes 34 via two orthogonal polarized gate layers and an FPGA controller. Notably, the pins of the PIN diodes 34 are connected to the polarized gate layer via a bent high-impedance line 35 and a metal pillar 36. This bent high-impedance line effectively prevents RF signals from entering the DC bias line. To ensure independent control of each PIN diode 34, its positive terminal is connected to a single metal strip in the polarized gate layer, while the negative terminals of the same column are connected to an independent terminal via a central ground line 32, and finally grounded to the GND terminal of the DC source via a connecting wire. Figure 7 As shown, in order to achieve beam scanning in different modes, a rectangular waveguide horn is used for feeding. By changing the on / off state of the PIN diode 34 in the unit and reasonably distributing the positions of each state, the transmission / reflection beam scanning switching can be achieved.

[0063] Figures 8a to 8g The phase compensation diagrams for the reconfigurable transmissive-reflective array antenna used in non-line-of-sight microwave propagation are shown in both transmission and reflection modes. Figure 8a This indicates that the deflection angle of the beam radiated by the antenna is 0°. Figure 8b This indicates that the deflection angle of the beam radiated by the antenna is 10°. Figure 8c This indicates that the deflection angle of the beam radiated by the antenna is 20°. Figure 8d This indicates that the deflection angle of the beam radiated by the antenna is 30°. Figure 8e This indicates that the deflection angle of the beam radiated by the antenna is 40°. Figure 8f This indicates that the deflection angle of the beam radiated by the antenna is 50°. Figure 8g This indicates that the deflection angle of the antenna's radiated beam is 60°. The yellow area in the diagram represents the phase compensation value required by the resonator at that location. In the diagram, blue indicates the phase compensation value required for the resonator at that location. .

[0064] Figure 9a and Figure 9b The figure shows the performance of the reconfigurable transflective array antenna for non-line-of-sight microwave propagation in transmission mode. In the figure, T... yx This indicates that the X-polarized incident wave is converted into a Y-polarized transmitted wave, T xx This indicates that the X-polarized incident wave is converted into an X-polarized transmitted wave; R yx This indicates that the X-polarized incident wave is converted into a Y-polarized reflected wave, R xx This indicates that the X-polarized incident wave is converted into an X-polarized reflected wave. From Figure 9a As can be seen, in states "01" and "10", the X-polarized incident wave will be converted into a Y-polarized transmitted wave. The insertion loss is less than -1 dB in the 8.9-9.8 GHz range, and the reflection coefficients of co-polarization and cross-polarization are less than -10 dB and -40 dB, respectively. The transmission coefficient of co-polarization is less than -40 dB, indicating that the transmitted wave has high cross-polarization purity. From... Figure 9b As can be seen, due to the symmetry of state "01" and state "10" about the y-axis, a phase shift of 180° occurs between the two states.

[0065] Figure 10a and Figure 10b The figure shows the performance of the reconfigurable transflective array antenna for non-line-of-sight microwave propagation in reflection mode. It can be seen from the figure that the resonant cavity formed by the polarization grating layer operates in a common-polarization state, without polarization switching. Figure 10a The results show that the co-polarization reflection loss is less than 0.3 dB, the cross-polarization reflection coefficient is less than -58 dB, and the transmission coefficients for both co-polarization and cross-polarization are less than 20 dB, indicating that total internal reflection occurs in both states without polarization conversion. Figure 10b As can be seen, there is a difference between state "00" and state "11" within the 8.9-9.7 GHz range. The phase difference can satisfy the control of 1-bit phase.

[0066] Figure 11 The diagram shows the radiation patterns of the XOZ and YOZ planes of this reconfigurable transflective array antenna for non-line-of-sight microwave propagation in transmission mode at 8.9, 9.3, and 9.7 GHz. Figure 11 (a) is the radiation pattern of the antenna in the XOZ plane at 8.9 GHz; Figure 11 (b) is the radiation pattern of the antenna in the XOZ plane at 9.3 GHz; Figure 11 (c) is the radiation pattern of the antenna in the XOZ plane at 9.7 GHz; Figure 11 (d) shows the radiation pattern of the antenna in the YOZ plane at 8.9 GHz; Figure 11 (e) shows the radiation pattern of the antenna in the YOZ plane at 9.3 GHz; Figure 11 (f) shows the radiation pattern of the antenna in the YOZ plane at 9.7 GHz. From the figure, it can be seen that at 9.3 GHz, the half-power beamwidths of the main polarization in the XOZ plane and YOZ plane are 11.4° and 8.4°, respectively, the sidelobe levels are less than -15.9 dB and -15.1 dB, respectively, and the cross-polarization level is less than -19.8 dB.

[0067] Figure 12 The figure shows the gain and aperture efficiency of the reconfigurable transflective array antenna for non-line-of-sight microwave propagation in transmission mode. As can be seen, the gain fluctuation is small within the target frequency band, with a maximum gain of 21.9 dBi at 9.4 GHz, corresponding to an aperture efficiency of 22%, and a 1-dB gain bandwidth of 8.55–9.95 GHz.

[0068] Figure 13a and Figure 13b This is a beam scan pattern at 10° intervals in transmission mode for a reconfigurable transmissive-reflective array antenna used for non-line-of-sight microwave propagation, according to one embodiment of the present invention. Figure 13a For XOZ side, Figure 13b This is the YOZ plane. As can be seen from the figure, the antenna has a beam scanning capability of ±60° in both planes, and the beam direction is consistent with the target angle. When the scanning angle increases, the main lobe beamwidth widens, the sidelobe horizontal beamwidth increases slightly, and the gain decreases.

[0069] Figure 14 This is an embodiment of the present invention showing the radiation patterns of the XOZ and YOZ planes of a reconfigurable transflective array antenna for non-line-of-sight microwave propagation in reflection mode at 8.9, 9.3, and 9.7 GHz. Figure 14 (a) is the radiation pattern of the antenna in the XOZ plane at 8.9 GHz; Figure 14(b) is the radiation pattern of the antenna in the XOZ plane at 9.3 GHz; Figure 14 (c) is the radiation pattern of the antenna in the XOZ plane at 9.7 GHz; Figure 14 (d) shows the radiation pattern of the antenna in the YOZ plane at 8.9 GHz; Figure 14 (e) shows the radiation pattern of the antenna in the YOZ plane at 9.3 GHz; Figure 14 (f) shows the radiation pattern of the antenna in the YOZ plane at 9.7 GHz. From the figure, it can be seen that at 9.3 GHz, the half-power beamwidths of the main polarization in the XOZ and YOZ planes are 11° and 8.5°, respectively, with sidelobe levels less than -10.9 dB and 15.2 dB, respectively, and the cross-polarization level less than -29.9 dB. The increase in sidelobe level is mainly due to the feed resistance plugging in the reflected beam. As the array size increases, the influence of the feed resistance plugging on the sidelobe level can be reduced.

[0070] Figure 15 This figure illustrates the gain and aperture efficiency of a reconfigurable transflective array antenna for non-line-of-sight microwave propagation in reflection mode, according to one embodiment of the present invention. As shown in the figure, within the target frequency band, the highest gain reaches 21.9 dBi at 9.1 GHz, corresponding to an aperture efficiency of 23.2%, and a 1-dB gain bandwidth of 8.75-9.25 GHz.

[0071] Figure 16a and Figure 16b This is a beam scan pattern at 10° intervals in reflection mode for a reconfigurable transflective array antenna used for non-line-of-sight microwave propagation, according to one embodiment of the present invention. Figure 16a For XOZ side, Figure 16b This is the YOZ plane. It can be seen that it has a beam scanning capability of ±50° in both planes, and the beam direction matches the target angle quite well. It is worth noting that in the XOZ plane scanning, the greater the main beam deviation angle, the smaller the sidelobes.

Claims

1. A reconfigurable transflective array antenna for non-line-of-sight microwave propagation, characterized in that, It includes a control circuit and sequentially arranged first polarization gate layer, first dielectric layer, M×N resonant plates, second dielectric layer, and second polarization gate layer, where M and N are natural numbers not less than 1, and M×N is not less than 2; The resonant plate includes a radiating section, four grounding wires, four extension sections, and two PIN diodes. The four extension sections are symmetrically arranged around the outer periphery of the radiating section and connected to the radiating section. Each extension section includes a first branch and two symmetrical second branches. One end of the first branch is connected to the radiating section, and the other end is connected to one end of the second branch. The other end of the second branch has a bent structure. The two PIN diodes are respectively arranged on two adjacent first branches. One PIN diode is connected to the first polarized gate layer via a bent line on the second branch and a metal pillar in the first dielectric layer. The other PIN diode is connected to the second polarized gate layer via a bent line on the second branch and a metal pillar in the second dielectric layer. The four grounding wires are symmetrically arranged around the outer periphery of the radiating section and spaced apart from the extension sections. The grounding wires of the resonant plates that are horizontally and vertically adjacent are all connected together. The grounding wires connect each of the radiating sections to DC ground. The first polarization gate layer is a plurality of first metal strips, and the second polarization gate layer is a plurality of second metal strips orthogonal to the first metal strips. The metal strips are connected to the control circuit, and the anodes of different PIN diodes are connected to different metal strips. The control circuit is used to control the conduction and disconnection of the PIN diodes. When the control circuit controls any one of the PIN diodes in the resonant plate to conduct, the resonant plate transmits a signal of a preset frequency. When the control circuit controls two PIN diodes in the resonant plate to conduct or disconnect simultaneously, the resonant plate reflects a signal of a preset frequency.

2. The reconfigurable transflective array antenna for non-line-of-sight microwave propagation as described in claim 1, characterized in that, The curved line is located at the position where the electric field of the resonator is weakest.

3. The reconfigurable transmissive-reflective array antenna for non-line-of-sight microwave propagation as described in claim 1, characterized in that, The first dielectric layer has a receiving groove opposite to the PIN diode, and the main body of the PIN diode is disposed in the receiving groove.

4. The reconfigurable transflective array antenna for non-line-of-sight microwave propagation as described in claim 1, characterized in that, The two PIN diodes have four states for being on and off: Status "00" indicates that both PIN diodes are disconnected; In state "01", the first PIN diode is off and the second PIN diode is on. In state "10", the first PIN diode is turned on, and the second PIN diode is turned off. In state "11", both PIN diodes are turned on; Specifically, in states "01" and "10", the signal transmitted by the resonator has a phase difference of 180°; in states "00" and "11", the signal reflected by the resonator has a phase difference of 180°±20°.

5. The reconfigurable transflective array antenna for non-line-of-sight microwave propagation as described in claim 4, characterized in that, In the antenna radiation preset direction When the beam is in the desired direction, the phase compensation required for each of the resonators to generate for the fed electromagnetic wave is: , , , The wavelength of the electromagnetic wave radiated by the antenna; In transmission mode, the state of the two PIN diodes in each of the resonant plates for: ； In reflection mode, the state of the two PIN diodes in each of the resonant plates for: ； In the formula, and These are the position vectors of the antenna feed and the resonator, respectively. This represents the optimized value for a one-dimensional spatially fed planar array.

6. The reconfigurable transflective array antenna for non-line-of-sight microwave propagation as described in claim 1, characterized in that, There are 16×16 resonant plates between the first dielectric layer and the second dielectric layer.

7. The reconfigurable transflective array antenna for non-line-of-sight microwave propagation as described in claim 1, characterized in that, Both the first dielectric layer and the second dielectric layer are F4-B substrates with a thickness of 1.8 mm, a dielectric constant of 2.65, and a loss tangent of 0.

001.

8. The reconfigurable transmissive-reflective array antenna for non-line-of-sight microwave propagation as described in claim 1, characterized in that, The control circuit is an FPGA controller; The metal strip is connected to the control circuit via a pin header and DuPont wires.

9. The reconfigurable transmissive-reflective array antenna for non-line-of-sight microwave propagation as described in claim 1, characterized in that, The center of the radiating section has several hollow structures.

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