An electrically tunable two-dimensional phased array linear array based on graphene nanosheets

Abstract

The application provides a graphene nanosheet-based electrically tunable two-dimensional phased array linear array, which comprises an upper dielectric plate, a lower dielectric plate, a graphene nanosheet-based electrically tunable antenna array and a Butler matrix feed network; the graphene nanosheet-based electrically tunable antenna array comprises a plurality of graphene nanosheet-based electrically tunable sub-arrays and a metal ground plate, each graphene nanosheet-based electrically tunable sub-array comprises two rectangular patches and one Wilkinson power divider loaded with graphene nanosheets; the upper dielectric plate, the metal ground plate and the lower dielectric plate are sequentially stacked, and the Butler matrix feed network comprises four directional couplers, two 45° phase shifters, two cross junctions and two 0° phase shifters. The graphene nanosheet-based electrically tunable two-dimensional phased array linear array can simplify the feed network and reduce the cost of the phased array.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wireless communication, and in particular to a graphene nanosheet-based electrically tunable two-dimensional phased array linear array. BACKGROUND

[0002] Due to the rapid development of technology, the research focus of modern communication systems is shifting towards intelligence and adjustability. Phased array antennas have the advantages of fast scanning speed, high scanning accuracy, low cost, light weight, low profile and easy integration, which make them play an important role in the field of 5G. However, they still have problems such as high complexity, high cost, low broadband performance and small scanning angle. Graphene material, as one of the nanomaterials that have attracted much attention in recent years, can be used as a new type of tunable microwave device material. Due to the difficulty in obtaining large-area high-quality single-layer graphene, in the microwave frequency band, few-layer graphene nanosheet is generally used as the main application material. By applying a direct current bias to the graphene nanosheet, the resistance of the graphene nanosheet can be dynamically tuned, which can be applied to two-dimensional directional pattern reconfigurable antennas. Traditional phased arrays require a large number of phase shifters, making the feed network complex and the cost of the phased array high. SUMMARY

[0003] The purpose of the present application is to provide a graphene nanosheet-based electrically tunable two-dimensional phased array linear array to solve the technical problems of complex feed network and high cost of phased array in the prior art.

[0004] The technical solution of the present application is as follows: a graphene nanosheet-based electrically tunable two-dimensional phased array linear array is provided, which comprises an upper dielectric plate, a lower dielectric plate, a graphene nanosheet-based electrically tunable antenna array and a Butler matrix feed network.

[0005] The graphene nanosheet-based electrically tunable antenna array comprises a plurality of graphene nanosheet-based electrically tunable sub-arrays and a metal ground plate, and the graphene nanosheet-based electrically tunable sub-array comprises two rectangular patches and one graphene nanosheet-loaded Wilkinson power divider.

[0006] The upper dielectric plate, the metal ground plate and the lower dielectric plate are sequentially stacked, the rectangular patches are arranged on one side of the upper dielectric plate away from the metal ground plate, the graphene nanosheet-loaded Wilkinson power divider and the Butler matrix feed network are arranged on one side of the lower dielectric plate away from the metal ground plate, and the Butler matrix feed network comprises four directional couplers, two 45° phase shifters, two cross junctions and two 0° phase shifters.

[0007] Further, the distance between the two rectangular patches is 0.3λ-0.4λ, wherein λ represents the wavelength.

[0008] Further, the output port of the graphene nanosheet loaded Wilkinson power divider is connected with the input port of the two rectangular patches through two vias.

[0009] Further, the two rectangular patches are fed by differential feeding, and the two rectangular patches are connected with a transmission line, and a preset length is added to the transmission line to compensate for the phase difference of the two rectangular patches.

[0010] Further, the graphene nanosheet loaded Wilkinson power divider includes four graphene nanosheets, and the four graphene nanosheets are connected with four metal branches respectively, and the length of the metal branches is λ / 4.

[0011] Further, two metal electrodes are connected with two surfaces of the graphene nanosheet respectively, and the two metal electrodes are connected with a voltage control panel through wires.

[0012] Further, the voltage control panel is used for adjusting the resistance of the graphene nanosheet, so that the graphene nanosheet loaded Wilkinson power divider realizes power adjustable distribution ratio, realizes input power control of the two rectangular patches, and realizes beam scanning in the xoz plane.

[0013] Further, the signal line of the Butler matrix feed network is arranged on the side of the lower layer dielectric plate away from the metal ground plate.

[0014] Further, the output port of the Butler matrix feed network is connected with the input port of the graphene nanosheet based electrically adjustable antenna array.

[0015] Further, the Butler matrix feed network is used for phase control of the graphene nanosheet based electrically adjustable antenna array to realize beam scanning in the yoz plane.

[0016] The beneficial effects of the application are that: by making the graphene nanosheet-based electrically tunable antenna array include a plurality of graphene nanosheet electrically tunable subarrays and a metal floor, the graphene nanosheet electrically tunable subarray includes 2 rectangular patches and a graphene nanosheet-loaded Wilkinson power divider; the upper dielectric plate, the metal floor, and the lower dielectric plate are sequentially stacked, the rectangular patches are arranged on one side of the upper dielectric plate away from the metal floor, the graphene nanosheet-loaded Wilkinson power divider and the Butler matrix feed network are arranged on one side of the lower dielectric plate away from the metal floor, the Butler matrix feed network includes 4 directional couplers, 2 45° phase shifters, 2 cross junctions, and 2 0° phase shifters; the voltage control board is used to adjust the graphene nanosheet resistance, so that the graphene nanosheet-loaded Wilkinson power divider realizes power-adjustable distribution ratio, realizes input power control of the 2 rectangular patches, and realizes beam scanning in the xoz plane; in combination with the beam control performance of the graphene nanosheet-loaded electrically tunable subarray and the phase adjustment function of the Butler matrix, two-dimensional beam scanning function in the xoz and yoz planes can be realized, with a simplified feed network, a low-cost and planar two-dimensional phased array antenna structure is realized. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The first structure schematic diagram of the graphene nanosheet-based electrically tunable two-dimensional phased array linear array of the embodiment of the application is shown in the figure.

[0018] Figure 2 The second structure schematic diagram of the graphene nanosheet-based electrically tunable two-dimensional phased array linear array of the embodiment of the application is shown in the figure.

[0019] Figure 3 The structure schematic diagram of the upper dielectric plate of the embodiment of the application is shown in the figure.

[0020] Figure 4 The structure schematic diagram of the lower dielectric plate of the embodiment of the application is shown in the figure.

[0021] Figure 5 The structure schematic diagram of the graphene nanosheet-loaded Wilkinson power divider of the embodiment of the application is shown in the figure. Figure 4 The enlarged view of A in the figure.

[0022] Figure 6 The structure schematic diagram of the graphene nanosheet-loaded Wilkinson power divider of the embodiment of the application is shown in the figure.

[0023] Figure 7 The structure schematic diagram of the metal floor of the embodiment of the application is shown in the figure.

[0024] Figure 8 The structure schematic diagram of the graphene nanosheet-loaded Wilkinson power divider of the embodiment of the application is shown in the figure. Figure 7 The enlarged view of B in the figure.

[0025] Figure 9A plot of S-parameters for a port of an electrically steerable graphene nanosheet based two-dimensional phased array linear array;

[0026] Figure 10 A first beam pattern for an electrically steerable graphene nanosheet based two-dimensional phased array linear array embodiment of the invention when energizing an input port;

[0027] Figure 11 A second beam pattern for an electrically steerable graphene nanosheet based two-dimensional phased array linear array embodiment of the invention when energizing an input port;

[0028] Figure 12 A third beam pattern for an electrically steerable graphene nanosheet based two-dimensional phased array linear array embodiment of the invention when energizing an input port;

[0029] Figure 13 A fourth beam pattern for an electrically steerable graphene nanosheet based two-dimensional phased array linear array embodiment of the invention when energizing an input port;

[0030] Figure 14 A fifth beam pattern for an electrically steerable graphene nanosheet based two-dimensional phased array linear array embodiment of the invention when energizing an input port;

[0031] Figure 15 A sixth beam pattern for an electrically steerable graphene nanosheet based two-dimensional phased array linear array embodiment of the invention when energizing an input port;

[0032] Figure 16 A seventh beam pattern for an electrically steerable graphene nanosheet based two-dimensional phased array linear array embodiment of the invention when energizing an input port;

[0033] Figure 17 An eighth beam pattern for an electrically steerable graphene nanosheet based two-dimensional phased array linear array embodiment of the invention when energizing an input port.

[0034] Figures: 1 - upper dielectric plate; 2 - metallic ground plate; 3 - lower dielectric plate; 4 - Butler matrix feed network; 5 - rectangular patch; 6 - Wilkinson power divider loaded with graphene nanosheets; 7 - via; 8 - directional coupler; 9 - 45° phase shifter; 10 - cross junction; 11 - 0° phase shifter; 12 - first transmission line; 13 - plastic screw; 14 - isolated circular slot; 15 - first metal stub; 16 - second metal stub; 17 - equal power Wilkinson power divider; 18 - second transmission line; 19 - connection pad; 20 - first graphene nanosheet; 21 - second graphene nanosheet; 22 - third graphene nanosheet; 23 - fourth graphene nanosheet; 24 - first input port; 25 - second input port; 26 - third input port; 27 - fourth input port. DETAILED DESCRIPTION

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0036] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0037] Figure 1 This is a schematic diagram of the first structure of an electrically tunable two-dimensional phased array linear array based on graphene nanosheets according to an embodiment of the present invention. It should be noted that, if substantially the same result is achieved, the electrically tunable two-dimensional phased array linear array based on graphene nanosheets of the present invention does not necessarily require... Figure 1 The structure shown is limited. This electrically tunable two-dimensional phased array linear array based on graphene nanosheets includes an upper dielectric substrate 1, a lower dielectric substrate 3, an electrically tunable antenna array based on graphene nanosheets, and a Butler matrix feeding network 4;

[0038] The electrically tunable antenna array based on graphene nanosheets includes multiple electrically tunable arrays of graphene nanosheets and a metal ground plane 2. The electrically tunable array of graphene nanosheets includes two rectangular patches 5 and one Wilkins power divider 6 loaded with graphene nanosheets.

[0039] The upper dielectric substrate 1, the metal ground plane 2, and the lower dielectric substrate 3 are stacked sequentially. The rectangular patch 5 is disposed on the side of the upper dielectric substrate 1 away from the metal ground plane 2. The Wilkins power divider 6 loaded with graphene nanosheets and the Butler matrix feed network 4 are disposed on the side of the lower dielectric substrate 3 away from the metal ground plane 2. The Butler matrix feed network 4 includes 4 directional couplers 8, 2 45° phase shifters 9, 2 cross junctions 10, and 2 0° phase shifters 11.

[0040] In one specific embodiment, the electrically tunable antenna array based on graphene nanosheets is a 1×4 electrically tunable antenna array based on graphene nanosheets, which includes four electrically tunable subarrays of graphene nanosheets and a metal ground plane 2. A schematic diagram of the second structure of the electrically tunable two-dimensional phased array linear array based on graphene nanosheets is shown below. Figure 2 As shown, Figure 2This can be a side view of an electrically tunable two-dimensional phased array linear array based on graphene nanosheets, in which an upper dielectric substrate 1, a metal ground plane 2, and a lower dielectric substrate 3 are stacked sequentially. Figure 1 An exploded view of an electrically tunable two-dimensional phased array linear array based on graphene nanosheets, excluding the metal ground plane 2.

[0041] In some embodiments, the spacing between the two rectangular patches 5 is 0.3λ to 0.4λ, where λ represents the wavelength.

[0042] In one specific embodiment, a schematic diagram of the upper dielectric substrate 1 is shown below. Figure 3 As shown, the rectangular patch 5 is disposed on the side of the upper medium plate 1 away from the metal floor 2.

[0043] In some embodiments, the two rectangular patches 5 are fed using a differential feeding method. The two rectangular patches 5 are connected to a transmission line (second transmission line 18). The phase difference between the two rectangular patches 5 is compensated by extending the transmission line by a preset length.

[0044] In one specific embodiment, Figure 3 The area within the dashed box represents the extended portion of the transmission line. By extending the transmission line by a preset length, the phase difference between the two rectangular patches 5 can be compensated.

[0045] In some embodiments, the output port of the Wilkins power divider 6 loaded with graphene nanosheets is connected to the input ports of the two rectangular patches 5 through two vias 7.

[0046] In this embodiment of the invention, the output port of the Wilkins power divider 6 loaded with graphene nanosheets is connected to the input ports of the two rectangular patches 5 through two vias 7, which facilitates signal transmission.

[0047] In some embodiments, the Wilkins power divider 6 loaded with graphene nanosheets includes four graphene nanosheets, each of which is connected to four metal branches, the length of which is λ / 4.

[0048] In one specific embodiment, a schematic diagram of the structure of the lower dielectric substrate 3 is shown below. Figure 4 As shown, four graphene nanosheets are connected to four metal branches, each with a length of λ / 4. The two symmetrical metal branches have the same width, while the two asymmetrical metal branches have different widths. The Wilkins power divider 6 loaded with graphene nanosheets can be a Wilkins power divider loaded with graphene nanosheets, that is, four graphene nanosheets loaded onto a single equal-power Wilkins power divider 17. Figure 4 Enlarged view of point A in the middle, as shown Figure 5 As shown, Figure 5 It includes a through hole 7 and an isolation circular gap 14.

[0049] In some embodiments, the graphene nanosheets are connected to two metal electrodes on each side, and the two metal electrodes are connected to a voltage control board via wires.

[0050] In one specific embodiment, metal electrodes are connected to the upper and lower surfaces of the graphene nanosheets, and the metal electrodes are connected to a voltage control board via DC lines (wires).

[0051] In some embodiments, the voltage control board is used to adjust the resistance of the graphene nanosheets so that the Wilkins power divider 6 loaded with graphene nanosheets can achieve an adjustable power distribution ratio, thereby controlling the input power of the two rectangular patches 5 to achieve beam scanning of the xoz plane.

[0052] In one specific embodiment, the resistance of the graphene nanosheets is controlled by a voltage control board. The adjustable range of the graphene nanosheet resistance is 10–300 ohms. Therefore, by dynamically adjusting the resistance of the graphene nanosheets, the adjustable power distribution ratio of the Wilkins power divider 6 loaded with graphene nanosheets can be achieved. By adjusting the distribution ratio of the Wilkins power divider 6 loaded with graphene nanosheets, the input power control of the two rectangular patches 5 is achieved, thereby realizing beam scanning in the xoz plane. A schematic diagram of the structure of the Wilkins power divider 6 loaded with graphene nanosheets is shown below. Figure 6 As shown, Figure 6 The four graphene nanosheets correspond to the first graphene nanosheet 20, the second graphene nanosheet 21, the third graphene nanosheet 22, and the fourth graphene nanosheet 23, respectively. The four metal branches include two first metal branches 15 and two second metal branches 16 with the same shape.

[0053] In some embodiments, the output port of the Butler matrix feed network 4 is connected to the input port of the electrically tunable antenna array based on graphene nanosheets.

[0054] In one specific embodiment, such as Figure 4 As shown, the output port of the Butler matrix feed network 4 is connected to the input port of the Wilkins power divider 6 loaded with graphene nanosheets in the electrically tunable antenna array based on graphene nanosheets by a transmission line (first transmission line 12).

[0055] In some embodiments, the Butler matrix feed network 4 is used to perform phase control on the electrically tunable antenna array based on graphene nanosheets to achieve beam scanning in the yoz plane.

[0056] In one specific embodiment, such as Figure 4As shown, the Butler matrix feed network 4 mainly consists of four directional couplers 8, two 45° phase shifters 9, two cross junctions 10, and two 0° phase shifters 11, with a symmetrical structure. The Butler feed network 4 achieves beam scanning in the yoz plane by performing phase control on the electrically tunable antenna array based on graphene nanosheets.

[0057] In some embodiments, the signal lines of the Butler matrix feed network 4 are disposed on the side of the lower dielectric substrate 3 away from the metal floor 2.

[0058] In one specific embodiment, a structural schematic diagram of the metal floor 2 is shown below. Figure 7 As shown, Figure 7 Enlarged view at point B, as shown Figure 8 As shown, Figure 8 In the middle, the isolation circular gap 14 of the pad is connected to the connecting pad 19 to prevent short circuit of the signal line. The upper dielectric board 1, the metal ground plate 2 and the lower dielectric board 3 are fixed with plastic screws 13.

[0059] In one specific embodiment, the S-parameter curves of the ports of an electrically tunable two-dimensional phased array linear array based on graphene nanosheets are shown below. Figure 9 As shown, Figure 9 In the graphene nanosheet 1, the first graphene nanosheet 20 is represented, and in the graphene nanosheet 3, the third graphene nanosheet 22 is represented. Figure 7 In the diagram, the first S11 represents the S-parameter of the first input port 24 when the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 40 ohms / sq; the first S22 represents the S-parameter of the second input port 25 when the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 40 ohms / sq; the second S11 represents the S-parameter of the first input port 24 when the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 300 ohms / sq; and the second S22 represents the S-parameter of the second input port 25 when the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 300 ohms / sq. Because the Butler matrix feed network 4 has a symmetrical structure, the S-parameters of the first input port 24 and the fourth input port 27 are essentially the same, and the S-parameters of the second input port 25 and the third input port 26 are also essentially the same. When input from different ports, its return loss at the center frequency of 3.5 GHz is below -10 dB, and energy can be effectively transmitted within this electrically tunable two-dimensional phased array based on graphene nanosheets.

[0060] In one specific embodiment, the input port of the Butler matrix feed network 4 can be the input port of an electrically tunable two-dimensional phased array linear array based on graphene nanosheets, such as... Figure 4As shown, the input ports of the Butler matrix feed network 4 may include a first input port 24, a second input port 25, a third input port 26, and a fourth input port 27. The first beam diagram of the electrically tunable two-dimensional phased array linear array based on graphene nanosheets when excited at the input ports is shown below. Figure 10 As shown, Figure 10 That is, the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 300 ohm / sq, and the sheet resistance of the second graphene nanosheet 21 and the fourth graphene nanosheet 23 is 40 ohm / sq, thus obtaining the two-dimensional beam pattern of the first input port 24 when the pitch angle θ is 43 degrees.

[0061] The second beam pattern of an electrically tunable two-dimensional phased array linear array based on graphene nanosheets at the excitation input port, as shown in the figure. Figure 11 As shown, Figure 11 That is, the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 40 ohm / sq, and the sheet resistance of the second graphene nanosheet 21 and the fourth graphene nanosheet 23 is 300 ohm / sq, thus obtaining the two-dimensional beam pattern of the first input port 24 when the pitch angle θ is 43 degrees.

[0062] like Figure 10 The pitch angle θ and azimuth angle Φ in the direction of the main lobe are (43°, 111°); while... Figure 11 In the figure, the pitch angle θ and azimuth angle Φ in the main lobe direction are (43°, 67°). It can be seen that by using the adjustable resistance of graphene nanosheets to control the adjustable power distribution ratio of the Wilkins power divider 6 loaded with graphene nanosheets, beam deflection can be achieved.

[0063] The third beam pattern of an electrically tunable two-dimensional phased array linear array based on graphene nanosheets at the excitation input port, as shown in the figure. Figure 12 As shown, Figure 12 That is, the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet is 300 ohm / sq, and the sheet resistance of the second graphene nanosheet 21 and the fourth graphene nanosheet 23 is 40 ohm / sq, thus obtaining the two-dimensional beam pattern of the second input port 25 when the pitch angle θ is 16 degrees.

[0064] The fourth beam pattern of an electrically tunable two-dimensional phased array linear array based on graphene nanosheets at the excitation input port, as shown in the figure. Figure 13 As shown, when the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 40 ohm / sq, and the sheet resistance of the second graphene nanosheet 21 and the fourth graphene nanosheet 23 is 300 ohm / sq, the two-dimensional beam pattern corresponding to the second input port 25 when the pitch angle θ is 16 degrees is obtained.

[0065] The fifth beam diagram of an electrically tunable two-dimensional phased array linear array based on graphene nanosheets at the excitation input port, as shown below. Figure 14 As shown, when the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 300 ohm / sq, and the sheet resistance of the second graphene nanosheet 21 and the fourth graphene nanosheet 23 is 40 ohm / sq, the two-dimensional beam pattern corresponding to the third input port 26 when the pitch angle θ is 16 degrees is obtained.

[0066] The sixth beam diagram of an electrically tunable two-dimensional phased array linear array based on graphene nanosheets at the excitation input port, as shown below. Figure 15 As shown, when the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 40 ohm / sq, and the sheet resistance of the second graphene nanosheet 21 and the fourth graphene nanosheet 23 is 300 ohm / sq, the two-dimensional beam pattern corresponding to the third input port 26 when the pitch angle θ is 16 degrees is obtained.

[0067] The seventh beam diagram of an electrically tunable two-dimensional phased array linear array based on graphene nanosheets at the excitation input port, as shown below. Figure 16 As shown, when the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 300 ohm / sq, and the sheet resistance of the second graphene nanosheet 21 and the fourth graphene nanosheet 23 is 40 ohm / sq, the two-dimensional beam pattern corresponding to the fourth input port 27 when the pitch angle θ is 43 degrees is obtained.

[0068] The eighth beam diagram of an electrically tunable two-dimensional phased array linear array based on graphene nanosheets at the excitation input port, as shown below. Figure 17 As shown, when the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 40 ohm / sq, and the sheet resistance of the second graphene nanosheet 21 and the fourth graphene nanosheet 23 is 300 ohm / sq, the two-dimensional beam pattern corresponding to the fourth input port 27 when the pitch angle θ is 43 degrees is obtained.

[0069] from Figures 10 to 17It is known that the sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 300 ohm / sq, and the sheet resistance of the second graphene nanosheet 21 and the fourth graphene nanosheet 23 is 40 ohm / sq. Excitation from different ports enables the Butler matrix feed network 4 to control the phase of the electrically tunable antenna array based on graphene nanosheets. The elevation angle θ and azimuth angle Φ of the first input port 24 to the fourth input port 27 are (43°, 111°), (16°, -135°), (16°, 135°) and (43°, -111°) respectively. The sheet resistance of the first graphene nanosheet 20 and the third graphene nanosheet 22 is 40 ohm / sq, and the sheet resistance of the second graphene nanosheet 21 and the fourth graphene nanosheet 23 is 300 ohm / sq. The elevation angle θ and azimuth angle Φ of the first input port 24 to the fourth input port 27 are (43°, 67°), (16°, -33°), (16°, 33°) and (43°, -67°) respectively. Therefore, it can be seen that the electrically tunable two-dimensional phased array linear array based on graphene nanosheets can realize two-dimensional beam scanning.

[0070] The electrically tunable two-dimensional phased array provided in this embodiment of the invention comprises multiple electrically tunable subarrays of graphene nanosheets and a metal ground plane 2. The electrically tunable subarrays of graphene nanosheets include two rectangular patches 5 and one Wilkins power divider 6 loaded with graphene nanosheets. The upper dielectric substrate 1, the metal ground plane 2, and the lower dielectric substrate 3 are stacked sequentially. The rectangular patches 5 are disposed on the side of the upper dielectric substrate 1 away from the metal ground plane 2. The Wilkins power divider 6 loaded with graphene nanosheets and the Butler matrix feed network 4 are disposed on the side of the lower dielectric substrate 3 away from the metal ground plane 2. The Butler matrix feed network 4 includes multiple directional couplers 8, two 45° phase shifters 9, multiple cross junctions 10, and two 0° phase shifters 11. This simplifies the feed network and reduces the cost of the phased array.

[0071] This invention provides an electrically tunable two-dimensional phased array linear array based on graphene nanosheets. By controlling the voltage on the graphene nanosheets, the resistance of the graphene is adjustable within the range of 10–300 ohms. Based on the adjustable resistance of the graphene nanosheets, a Wilkins power divider 6 can be added to achieve an adjustable power division ratio, thereby enabling input power control of the two rectangular patches 5 and allowing beam scanning in the xoz plane. Utilizing the different sheet resistance values ​​of the graphene nanosheets, the equal power division Wilkins power divider 17 can output unequal power division ratios without changing the structure, thus allowing the unit composed of two patch antennas to achieve beams at different angles. Compared with other two-dimensional beam scanning antenna arrays, the electrically tunable two-dimensional phased array linear array based on graphene nanosheets provided by this invention reduces the use of phase shifters, simplifies the feeding network, and achieves two-dimensional beam scanning through a simple structure.

[0072] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0073] The above embodiments merely illustrate preferred implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention should be determined by the appended claims.

Claims

1. An electrically tunable two-dimensional phased array linear array based on graphene nanosheets, characterized in that, It includes an upper dielectric substrate, a lower dielectric substrate, an electrically tunable antenna array based on graphene nanosheets, and a Butler matrix feed network; The graphene nanosheet-based electrically tunable antenna array comprises multiple graphene nanosheet electrically tunable subarrays and a metal ground plane. The graphene nanosheet electrically tunable subarray includes two rectangular patches and one graphene nanosheet-loaded Wilkins power divider. The output port of the graphene nanosheet-loaded Wilkins power divider is connected to the input ports of the two rectangular patches via two vias. The two rectangular patches are fed using a differential feeding method and are connected to a transmission line. The phase difference between the two rectangular patches is compensated by extending the transmission line by a predetermined length. The graphene nanosheet-loaded Wilkins power divider comprises four graphene nanosheets, each connected to four metal stubs. The length of each metal stub is λ / 4, where λ represents the wavelength. The upper dielectric substrate, the metal ground plane, and the lower dielectric substrate are stacked sequentially. The rectangular patch is disposed on the side of the upper dielectric substrate away from the metal ground plane. The Wilkins power divider loaded with graphene nanosheets and the Butler matrix feed network are disposed on the side of the lower dielectric substrate away from the metal ground plane. The Butler matrix feed network includes four directional couplers, two 45° phase shifters, two cross junctions, and two 0° phase shifters.

2. The electrically tunable two-dimensional phased array linear array based on graphene nanosheets according to claim 1, characterized in that, The spacing between the two rectangular patches is 0.3λ~0.4λ.

3. The electrically tunable two-dimensional phased array linear array based on graphene nanosheets according to claim 1, characterized in that, The graphene nanosheet is connected to two metal electrodes on each side, and the two metal electrodes are connected to a voltage control board via wires.

4. The electrically tunable two-dimensional phased array linear array based on graphene nanosheets according to claim 3, characterized in that, The voltage control board is used to adjust the resistance of the graphene nanosheets so that the Wilkins power divider loaded with graphene nanosheets can achieve an adjustable power distribution ratio, thereby controlling the input power of the two rectangular patches to achieve beam scanning in the xoz plane.

5. The electrically tunable two-dimensional phased array linear array based on graphene nanosheets according to claim 1, characterized in that, The signal lines of the Butler matrix feed network are located on the side of the lower dielectric substrate away from the metal floor.

6. The electrically tunable two-dimensional phased array linear array based on graphene nanosheets according to claim 5, characterized in that, The output port of the Butler matrix feed network is connected to the input port of the electrically tunable antenna array based on graphene nanosheets.

7. The electrically tunable two-dimensional phased array linear array based on graphene nanosheets according to claim 6, characterized in that, The Butler matrix feed network is used to perform phase control on the electrically tunable antenna array based on graphene nanosheets to achieve beam scanning in the yoz plane.

Images