Multi-segment antenna element and phased array antenna

Abstract

The present invention relates to the field of satellite communication technologies, and particularly to a multi-branch antenna unit and a phased array antenna. The multi-branch antenna unit includes: a multi-branch radiation structure and a feeding structure; the multi-branch radiation structure includes: first to third flat plates symmetrically arranged, with adjacent two flat plates respectively forming first to second branches; the feeding structure includes: a rectangular metal cavity, a dielectric substrate, a first port, a second port, two feeding probes, and a microstrip line; the first port and the second port are symmetrically arranged at the bottom of the feeding structure, and the first port and the second port are respectively connected to both ends of the microstrip line through the feeding probes; the dielectric substrate is arranged inside the rectangular metal cavity. The external feeding power source is respectively excited through the first port or the second port to form two radiation beams with symmetrical directions. Only the amplitude-phase control of one sub-scanning area needs to be provided to achieve the beam scanning of the entire space. Meanwhile, the gain drop is small, and flat scanning gain can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of satellite communication, and in particular to a multi-branch antenna element and a phased array antenna. Background Art

[0002] As one of the most important components of a satellite communication link, the performance of an antenna directly determines the quality of satellite communication. In current medium and low earth orbit high-throughput satellite communication systems, parabolic antennas are mostly used as communication terminals, but they have the defects of large profile, inflexible beam control, low integration, and high maintenance cost, and it is difficult to meet the requirements of satellite-ground high-speed interconnection communication in the context of low-earth orbit satellite Internet. Phased array antennas can achieve beam control, but phased array antennas generally have a large gain drop when scanning at large angles, which greatly affects the communication performance of phased arrays during the process of tracking satellites, resulting in a reduced effective communication range. When the phased array reaches the maximum scanning angle, the antenna gain is much lower than the maximum normal gain, and flat scanning gain cannot be achieved.

[0003] The above content is only used to assist in understanding the technical solution of the present invention, and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The main object of the present invention is to provide a multi-branch antenna element and a phased array antenna, aiming to solve the technical problem that the antenna gain of the phased array antenna drops significantly when scanned to the maximum angle compared with the normal direction in the prior art.

[0005] To achieve the above object, the present invention proposes a multi-branch antenna element, which includes: a multi-branch radiation structure and a feeding structure;

[0006] The multi-branch radiation structure includes: the first to third flat plates symmetrically arranged, and the adjacent two flat plates respectively form the first to second branches;

[0007] The feeding structure includes: a rectangular metal cavity, a dielectric substrate, a first port, a second port, two feeding probes, and a microstrip line;

[0008] The first port and the second port are symmetrically arranged at the bottom of the feeding structure, and the first port and the second port are respectively connected to both ends of the microstrip line through the feeding probes;

[0009] The dielectric substrate is arranged in the rectangular metal cavity, and the multi-branch radiation structure is arranged above the rectangular metal cavity;

[0010] An external feeding power source excites the microstrip line through the first port or the second port, forms an electromagnetic field, and then feeds it into the multi-branch radiation structure to form a radiation beam.

[0011] Optionally, the dielectric substrate includes, from bottom to top: a first dielectric layer and a second dielectric layer;

[0012] The first dielectric layer and the second dielectric layer have the same thickness;

[0013] The first port and the second port are disposed at the bottom of the first dielectric layer, both of the feeding probes are disposed inside the first dielectric layer, and the microstrip line is disposed at the interface between the first dielectric layer and the second dielectric layer.

[0014] Optionally, in the multi-branch radiation structure, the symmetrically arranged first flat plate and the third flat plate are set to the same first preset height, the second flat plate is set to a second preset height, and the first to third flat plates are set to the same first preset thickness;

[0015] The first flat plate and the second flat plate form a first branch, and the second flat plate and the third flat plate form a second branch;

[0016] The first branch and the second branch have the same first preset spacing.

[0017] Optionally, the radiation beam direction and width are adjusted according to the first preset height, the second preset height, the first preset thickness, and the first preset spacing.

[0018] Optionally, the height of the rectangular metal cavity is twice the thickness of the first dielectric layer.

[0019] In addition, to achieve the above object, the present invention further provides a phased array antenna, which includes a plurality of multi-branch antenna units as described above and T / R components corresponding to the number of the multi-branch antenna units.

[0020] Optionally, the phased array antenna includes: N multi-branch antenna units arranged in a one-dimensional array, where N is an integer greater than 1;

[0021] Adjacent multi-branch antenna units are connected in series through the T / R components.

[0022] Optionally, the phased array antenna includes: M*M multi-branch antenna units arranged in a rectangular array, where M is an integer greater than 1;

[0023] The phased array antenna further includes: a one-to-M power divider;

[0024] The multi-branch antenna units in one direction of the rectangular array are combined through the one-to-M power divider to form 2M input ports of the one-to-M power divider;

[0025] Except for the first and the last one, the input ports of the remaining adjacent one-in-M power dividers among the 2M one-in-M power dividers are connected in series through the T / R components.

[0026] Optionally, the phased array antenna includes: N multi-branch antenna units arranged in a one-dimensional array, where N is an integer greater than 1, and the adjacent multi-branch antenna units are connected in parallel.

[0027] The phased array antenna further includes: a one-in-N power divider and N single-pole double-throw switches.

[0028] The input end of each T / R component is connected to the output port of the one-in-N power divider, the output end of each T / R component is connected to the input end of a single-pole double-throw switch, and the two output ends of each single-pole double-throw switch are respectively connected to the first port and the second port of the corresponding multi-branch antenna unit.

[0029] Optionally, the phased array antenna includes: M*M multi-branch antenna units arranged in a rectangle.

[0030] The phased array antenna further includes: a one-in-M power divider and single-pole double-throw switches.

[0031] The multi-branch antenna units in one direction of the rectangle array are combined through the one-in-M power divider to form the input ports of 2M one-in-M power dividers.

[0032] The input ports of the adjacent one-in-M power dividers are connected through the two output ports of the single-pole double-throw switch, and the input end of the single-pole double-throw switch is connected to the output end of the corresponding T / R component.

[0033] The present invention provides a multi-branch antenna unit and a phased array antenna. The multi-branch antenna unit includes: a multi-branch radiation structure and a feeding structure; the multi-branch radiation structure includes: first to third flat plates symmetrically arranged, and the adjacent two flat plates respectively form first to second branches; the feeding structure includes: a rectangular metal cavity, a dielectric substrate, a first port, a second port, two feeding probes, and a microstrip line; the first port and the second port are symmetrically arranged at the bottom of the feeding structure, and the first port and the second port are respectively connected to both ends of the microstrip line through the feeding probes; the dielectric substrate is arranged in the rectangular metal cavity; an external feeding power source excites the microstrip line through the first port or the second port, forms an electromagnetic field, and then feeds it into the multi-branch radiation structure to form a radiation beam. The external feeding power source is respectively excited through the first port or the second port to form two radiation beams with symmetric directions. Only one sub-scanning area's amplitude and phase control is required to achieve the beam scanning of the entire space. At the same time, the gain drop is small, and flat scanning gain can be achieved. Description of the Drawings

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on the structures shown in these drawings.

[0035] Figure 1 Structural schematic diagram of the first embodiment of the multi-branch antenna unit of the present invention;

[0036] Figure 2 Structural schematic diagram of the multi-branch radiation structure in the first embodiment of the multi-branch antenna unit of the present invention;

[0037] Figure 3 Front view of the structure of the multi-branch radiation structure in the first embodiment of the multi-branch antenna unit of the present invention;

[0038] Figure 4 Side view of the structure of the multi-branch radiation structure in the first embodiment of the multi-branch antenna unit of the present invention;

[0039] Figure 5 Structural schematic diagram of the distribution of the feeding structure and the dielectric layer in the first embodiment of the multi-branch antenna unit of the present invention;

[0040] Figure 6 Structural schematic diagram of the feeding structure in the first embodiment of the multi-branch antenna unit of the present invention;

[0041] Figure 7 Top view of the structure of the feeding structure in the first embodiment of the multi-branch antenna unit of the present invention;

[0042] Figure 8 Radiation pattern generated by different ports of the excitation antenna unit in the first embodiment of the multi-branch antenna unit of the present invention;

[0043] Figure 9 Electric field schematic diagram of the TEM mode formed by the feeding structure in the first embodiment of the multi-branch antenna unit of the present invention;

[0044] Figure 10 Magnetic field schematic diagram of the TEM mode formed by the feeding structure in the first embodiment of the multi-branch antenna unit of the present invention;

[0045] Figure 11 Structural schematic diagram of the first embodiment of the phased array antenna of the present invention;

[0046] Figure 12 Structural schematic diagram of the second embodiment of the phased array antenna of the present invention;

[0047] Figure 13 Schematic diagram of the feed port distribution of the second embodiment of the phased array antenna of the present invention;

[0048] Figure 14 Schematic diagram of the structure of the third embodiment of the phased array antenna of the present invention;

[0049] Figure 15 Schematic diagram of the structure of the fourth embodiment of the phased array antenna of the present invention;

[0050] Figure 16 Schematic diagram of the feed port distribution of the fourth embodiment of the phased array antenna of the present invention;

[0051] Figure 17 Beam scanning direction diagrams of the first and third embodiments of the phased array antenna of the present invention;

[0052] Figure 18 Beam scanning direction diagrams of the second and fourth embodiments of the phased array antenna of the present invention.

[0053] The realization, functional characteristics and advantages of the present invention will be further described with reference to the embodiments and the accompanying drawings. Detailed implementation manners

[0054] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0055] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0056] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0057] In addition, the descriptions involving "first", "second", etc. in the present invention are for descriptive purposes only, and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments may be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0058] The main solution of the embodiment of the present invention is that the multi-branch antenna unit includes: a multi-branch radiation structure and a feeding structure; the multi-branch radiation structure includes: first to third flat plates symmetrically arranged, and adjacent two flat plates respectively form first to second branches; the feeding structure includes: a rectangular metal cavity, a dielectric substrate, a first port, a second port, two feeding probes and a microstrip line; the first port and the second port are symmetrically arranged at the bottom of the feeding structure, and the first port and the second port are respectively connected to both ends of the microstrip line through the feeding probes; the dielectric substrate is arranged in the rectangular metal cavity; an external feeding power source excites the microstrip line through the first port or the second port, and after forming an electromagnetic field, it is fed into the multi-branch radiation structure to form a radiation beam.

[0059] In the current medium and low earth orbit high-throughput satellite communication system, parabolic antennas are mostly used as communication terminals, but they have a large profile, inflexible beam control, low integration, and high maintenance costs, making it difficult to meet the requirements of satellite-ground high-speed interconnection communication in the context of low-earth orbit satellite Internet. Phased array antennas have advantages such as high integration, fast beam scanning, and flexible beam control (beamforming, multi-beam), and have important applications in satellite communication and other fields at present. However, phased array antennas generally have the problem of gain drop during large-angle scanning, which greatly affects the communication performance of phased arrays during satellite tracking, resulting in a reduced effective communication range.

[0060] Continuous Transverse Stub (CTS) array antennas have been widely used in the terminals of mobile communication systems. Since the transverse stubs of CTS cut off the longitudinal conduction current, generating displacement current, which can thus radiate outward. Currently, the types of CTS antennas with beam scanning capabilities are electrically scanned CTS antennas, Variable Inclination Continuous Transverse Stub (VICTS) antennas, and frequency-scanned CTS antennas. Among them, the frequency-scanned CTS antenna cannot generate beam pointing at different angles at a fixed frequency.

[0061] When the front phased array reaches the maximum scanning angle, the antenna gain drops significantly compared to the maximum normal gain, and flat scanning gain cannot be achieved. The pseudo-curved surface conformal (PCSC) phased array antenna with a planar structure has a high sidelobe level after arraying because different beam-tilted antenna elements are used. The VICTS antenna utilizes series-fed CTS stubs, and the beam scanning is achieved by changing the wavefront phase of the TEM wave generated by the feed source through the relative rotation of the feed layer and the radiation layer. The feeding structure of the VICTS is complex. Moreover, the current VICTS antenna has a gain drop greater than 3 dB within the scanning range, and flat scanning gain cannot be achieved.

[0062] Referring to Figure 1 , Figure 1 is a schematic structural diagram of the first embodiment of the multi-stub antenna element of the present invention. As Figure 1 shown, in this embodiment, the multi-stub antenna element includes: a multi-stub radiation structure 10 and a feeding structure 20. The multi-stub radiation structure 10 includes: a first to a third flat plate symmetrically arranged, and two adjacent flat plates respectively form a first stub and a second stub. The feeding structure 20 includes: a first port 201, a second port 202, two feeding probes 203, a microstrip line 204, a rectangular metal cavity 205, and a dielectric substrate; the first port 201 and the second port 202 are symmetrically arranged at the bottom of the feeding structure 20, and the first port 201 and the second port 202 are respectively connected to both ends of the microstrip line 204 through the feeding probes 203; the dielectric substrate is arranged in the rectangular metal cavity 205, and the multi-stub radiation structure 10 is arranged above the rectangular metal cavity 205.

[0063] It should be noted that the multi-stub antenna element proposed in this embodiment can be a CTS antenna element. The external feed power source excites the microstrip line through the first port or the second port, forms an electromagnetic field, and then feeds it into the multi-stub radiation structure to form a radiation beam. The external feed power source respectively excites through the first port or the second port to form two symmetric radiation beams pointing to ±35°. The phased array antenna composed of antenna elements in this embodiment only needs to provide amplitude-phase control in a sub-scanning area to achieve beam scanning in the entire scanning space (-65° to 65°). The gain drop in the entire scanning space (-65° to 65°) is small, less than 2 dBi, and flat scanning gain can be achieved.

[0064] Referring to Figure 2 , Figure 3 and Figure 4 , Figure 2 is a schematic structural diagram of the multi-stub radiation structure in the first embodiment of the multi-stub antenna element of the present invention. Figure 3This is the front view of the multi-branch radiation structure in the first embodiment of the multi-branch antenna unit of the present invention. Figure 4 This is the side view of the multi-branch radiation structure in the first embodiment of the multi-branch antenna unit of the present invention. In the multi-branch radiation structure 10, the symmetrically arranged first flat plate 101 and the third flat plate 103 have the same first preset height (h2), the second flat plate 102 is set to a second preset height (h1), and the first to third flat plates have the same first preset thickness (w2). The first flat plate 101 and the second flat plate 102 form the first branch 104, the second flat plate 102 and the third flat plate 103 form the second branch 105, and the first branch 104 and the second branch 105 have the same first preset spacing (w1). Among them, the second preset height (h1) needs to be greater than the first preset height (h2), that is, the height of the second flat plate is greater than that of the first flat plate and the third flat plate so that the beam direction of the antenna unit deflects. Different deflections of the beam direction of the antenna unit can be achieved by adjusting the specific values of the first preset height (h2), the second preset height (h1), and the first preset spacing (w1).

[0065] In a possible implementation, the first preset height (h2) can be set to 11.5 mm, the second preset height (h1) to 16 mm, and the first preset spacing (w1) to 4.82 mm, and by feeding the first port and the second port respectively, the antenna unit generates beam directions of ±35°.

[0066] Refer to Figure 5 、 Figure 6 and Figure 7 , Figure 5 This is the schematic structural diagram of the feeding structure and the dielectric layer distribution in the first embodiment of the multi-branch antenna unit of the present invention. Figure 6 This is the schematic structural diagram of the feeding structure in the first embodiment of the multi-branch antenna unit of the present invention. Figure 7 This is the top view of the feeding structure in the first embodiment of the multi-branch antenna unit of the present invention. The feeding structure of the multi-branch antenna unit of the present invention is composed of a rectangular metal cavity and a dielectric substrate. The dielectric substrate includes, from bottom to top: a first dielectric layer 206 and a second dielectric layer 207. The thickness of the rectangular metal cavity is w3, and the length, width, and height of the rectangular metal cavity are D1, L1, and h3 respectively. Figure 6On the upper surface of the first dielectric layer 206, a microstrip line with a width of D2 and a length of L2 is covered. Two symmetrically positioned feeding probes are connected to the microstrip line. The heights of the two feeding probes are the same as the height of the first dielectric layer 206. The GND is located on the bottom surface of the first dielectric layer 206, and openings are made in the GND as the feeding ports for the two feeding probes, namely the first port and the second port. The characteristic impedance of the feeding ports can be set to 50 Ω. The second dielectric layer 207 covers the first dielectric layer 206. Among them, the dielectric layer can be composed of F4B dielectric (a high-frequency board made of polytetrafluoroethylene material).

[0067] It should be noted that the radiation beam direction and width are adjusted according to the first preset height (h2), the second preset height (h1), the first preset thickness (w2), and the first preset spacing (w1). It can make the main beam direction of the radiation pattern of the multi-branch CTS antenna unit point to ±35° respectively and have a 2dB beam width greater than 65°. That is, when feeding the first port, the main radiation beam direction of the radiation direction of the multi-branch antenna unit is +35°, and when feeding the second port, the main radiation beam direction of the radiation direction of the antenna unit is -35°. The shapes of the two radiation patterns are symmetrical. Refer to Figure 8 , Figure 8 This is the radiation pattern generated by exciting different ports of the exciting antenna unit in the first embodiment of the multi-branch antenna unit of the present invention. Among them, the 2dB beam width is greater than 65°.

[0068] It should be understood that by exciting the microstrip line through the feeding probe, the excited microstrip line forms an electromagnetic field in the TEM (Transverse Electromagnetic) mode in the feeding structure composed of a rectangular metal cavity and a dielectric layer (as Figure 5 shown). The electromagnetic field in the TEM mode is fed into the CTS branches of the antenna unit to form radiation. Refer to Figure 9 and Figure 10 , Figure 9 This is a schematic diagram of the electric field in the TEM mode formed by the feeding structure in the first embodiment of the multi-branch antenna unit of the present invention, Figure 10 This is a schematic diagram of the magnetic field in the TEM mode formed by the feeding structure in the first embodiment of the multi-branch antenna unit of the present invention.

[0069] In this embodiment, the multi-branch antenna unit includes: a multi-branch radiation structure and a feeding structure; the multi-branch radiation structure includes: first to third flat plates symmetrically arranged, and adjacent two flat plates respectively form first to second branches; the feeding structure includes: a rectangular metal cavity, a dielectric substrate, a first port, a second port, two feeding probes and a microstrip line; the first port and the second port are symmetrically arranged at the bottom of the feeding structure, and the first port and the second port are respectively connected to both ends of the microstrip line through the feeding probes; the dielectric substrate is arranged in the rectangular metal cavity; an external feeding power source excites the microstrip line through the first port or the second port, forms an electromagnetic field and then feeds it into the multi-branch radiation structure to form a radiation beam. The external feeding power source respectively excites through the first port or the second port to form two symmetric radiation beams pointing to ±35°. Using this embodiment as the antenna unit to form a phased array antenna only needs to provide amplitude-phase control in a sub-scanning area to achieve beam scanning in the entire scanning space (-65° to 65°). The gain drop in the entire scanning space (-65° to 65°) is small, less than 2 dBi, and flat scanning gain can be achieved. The main radiation directions of the multi-branch CTS antenna unit under different port excitations are respectively towards ±35°, and a 2 dB beam width greater than 65° is formed in the main radiation beam direction, and the two generated radiation patterns are symmetric.

[0070] In addition, to achieve the above object, an embodiment of the present invention further provides a phased array antenna, which includes a plurality of the above-mentioned multi-branch antenna units and corresponding T / R components. Since the phased array antenna includes the above-mentioned multi-branch antenna unit, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, and will not be elaborated here one by one.

[0071] Refer to Figure 11 , Figure 11 is a schematic structural diagram of the first embodiment of the phased array antenna of the present invention. As Figure 11As shown, in this embodiment, the phased array antenna is a one-dimensional series-fed phased array antenna, including: N multi-branch antenna elements arranged in one dimension, where N is an integer greater than 1; adjacent multi-branch antenna elements are serially fed and connected through the T / R module. It can perform beam scanning in the yoz plane from (-65° to 65°). In this embodiment, a one-dimensional 8-element series-fed phased array antenna is taken as an example for illustration. Among them, the one-dimensional 8-element series-fed phased array antenna includes: the feeding port (①) of the antenna element, and the T / R module (②). The T / R module can be a Transmit / Receive module, which is composed of a power amplifier and a phase shifter, and is used for amplifying the signals transmitted and received by the antenna and controlling the pointing direction of the antenna radiation beam. In the arrangement direction y of the array, except for the first port (Port1) and the last port (Port2), the adjacent two ports of the antenna element are sequentially connected to the input end (In) and the output end (Out) of the T / R module (②).

[0072] It should be noted that by using the symmetry of the designed multi-branch antenna element structure, the T / R module only needs to provide amplitude-phase control for one sub-scanning area to achieve beam scanning in the entire scanning space from (-65° to 65°). The scanning range (-65° to 65°) of the phased array is divided into two sub-scanning areas (-65° to 0°) and (0° to 65°) with 0° as the dividing line. When feeding the feeding port (port1) of the one-dimensional 8-element series-fed phased array antenna as shown Figure 11 in the figure, the antenna will scan in the range of 0 - 65°; when using the amplitude-phase control of the sub-scanning area (0° to 65°) to feed the feeding port (port2) of the phased array antenna, the antenna will scan in the range of (-65° to 0°).

[0073] It should be understood that it is also possible to use multiple other types of structures, such as an antenna element with two feeding ports formed by combining different types of coupling structures. When the feeding port (Port1) is excited, the main beam of the radiation pattern of the antenna element points to a specific direction and the 2dB beam width of the pattern covers a certain angular range. When the feeding port (Port2) is excited, the main beam of the radiation beam of the antenna element points in the opposite direction to the main beam obtained by exciting the feeding port (Port1), and the pattern shapes obtained by exciting the feeding port (Port1) and the feeding port (Port2) of the antenna element are symmetric. After forming a phased array antenna with the antenna elements, by using the symmetry of the designed antenna element structure, the scanning range of the phased array is divided into two left and right sub-scanning areas with 0° as the dividing line. The T / R module only needs to provide amplitude-phase control for one sub-scanning area to achieve beam scanning within a certain range. Within a certain beam scanning range, the gain drop of the phased array antenna is small, the gain change of the scanning beam is flat, and flat scanning gain can be achieved.

[0074] In a possible implementation, an antenna unit formed by a coupling structure composed of multiple magnetic current elements, or an antenna unit formed by a coupling structure composed of multiple current sources, and an antenna unit formed by a coupling structure composed of a mixture of multiple magnetic current sources and current sources; for example, an antenna unit formed by a coupling structure composed of a combination of multiple electric dipole antennas and slot antennas, an antenna unit formed by a coupling structure composed of a combination of multiple electric dipole antennas and microstrip antennas, an antenna unit formed by a coupling structure composed of multiple microstrip antennas, an antenna unit formed by a coupling structure composed of multiple slot antennas, an antenna unit formed by a coupling structure composed of multiple electric dipole antennas, etc.; and adding a perturbation unit beside the antenna or using an asymmetric structure to change the main beam direction of the antenna radiation pattern so that it points to a specific direction.

[0075] Refer to Figure 12 , Figure 12 is a schematic structural diagram of the second embodiment of the phased array antenna of the present invention. As Figure 12 shown, in this embodiment, the phased array antenna is a two-dimensional series-fed phased array antenna, and the antenna includes: the multi-branch antenna units arranged in an M*M rectangle, where M is an integer greater than 1. The phased array antenna further includes: a one-to-M power divider and a T / R component. Figure 13 is a schematic diagram of the feed port distribution of the second embodiment of the phased array antenna of the present invention. This embodiment is described by taking a two-dimensional 8*8 unit series-fed phased array antenna as an example. Among them, the one-to-eight power divider (③) is used to combine the feed ports of the antenna units in the array.

[0076] As Figure 13 shown, there are 16 columns of feed ports arranged along the x direction of the 8*8 array antenna, and each column has 8 feed ports. There are 8 rows of feed ports arranged along the y direction. As Figure 12 shown, each column of feed ports arranged along the x direction of the two-dimensional series-fed phased array antenna is combined by a one-to-eight power divider (③) to form 16 input ports of the power divider (③). The 16 input ports of the power divider (③) are respectively labeled A1 to A16. Except for the ports A1 and A16 at both ends of the array, the adjacent two ports of A2 to A15 are sequentially connected to the input and output ends of the T / R component (②) (A2 is connected to the input port of the T / R component, A3 is connected to the output port of the T / R component, and so on in sequence) to form a two-dimensional series-fed phased array antenna. This two-dimensional series-fed phased array antenna can perform beam scanning in the yoz plane (-65° to 65°).

[0077] Similar to the first embodiment of the above phased array antenna, by using the symmetry of the designed antenna unit structure, the T / R component only needs to provide amplitude-phase control in one sub-scanning area to achieve beam scanning in the entire scanning space (-65° to 65°). When for Figure 12When feeding the feeding port (port1) of the shown 8×8 element phased array antenna, the antenna will scan in the range of 0° to 65°; when feeding the feeding port (port2) of the 8×8 element phased array antenna, the antenna will scan in the range of -65° to 0°, and finally perform beam scanning within the range of ±65°.

[0078] Referring to Figure 14 , Figure 14 is a schematic structural diagram of the third embodiment of the phased array antenna of the present invention. As Figure 14 shown, in this embodiment, the phased array antenna is a one-dimensional parallel-fed phased array antenna, including: N one-dimensionally arranged multi-branch antenna elements, and adjacent multi-branch antenna elements are parallel-fed; the phased array antenna includes: N one-dimensionally arranged multi-branch antenna elements, where N is an integer greater than 1, and adjacent multi-branch antenna elements are parallel-fed. The phased array antenna further includes: a one-to-N power divider and N single-pole double-throw switches; the input ends of each T / R component are connected to the output ports of the one-to-N power divider, the output ends of each T / R component are connected to the input end of a single-pole double-throw switch, and the two output ends of each single-pole double-throw switch are respectively connected to the feeding ports of the corresponding multi-branch antenna elements. The T / R component only needs to provide amplitude-phase control for one sub-scanning area and can realize beam scanning in the yoz plane (-65° to 65°) by switching different feeding ports of the antenna element through the single-pole double-throw switch.

[0079] This embodiment is described by taking a one-dimensional 8-element parallel-fed phased array antenna as an example. The one-to-eight power divider (④) is used to combine the signals at the input ports of the T / R components (②). As Figure 14 shown, the two feeding ports of each antenna element are connected to the output ends of the single-pole double-throw switch, the output end of the T / R component (②) is connected to the input end of the single-pole double-throw switch, and the input port of the T / R component is connected to the output port of the one-to-eight power divider (④). When the one-dimensional 8-element parallel-fed phased array antenna works, by feeding the input end of the one-to-eight power divider (④), the T / R component only needs to provide amplitude-phase control for one sub-scanning area and can realize beam scanning in the yoz plane (-65° to 65°) by switching different feeding ports of the antenna element through the single-pole double-throw switch. Specifically, when feeding the input end of the one-to-eight power divider (④) and simultaneously turning all the single-pole double-throw switches to the left to connect the B-group ports (the B-group ports are composed of 8 ports from port B1 to B8), the 8 one-dimensionally arranged phased array antennas realize spatial beam scanning in the range of (0 - 65°); when simultaneously turning all the single-pole double-throw switches to the right to connect the C-group ports (the C-group ports are composed of 8 ports from port C1 to C8), the 8 one-dimensionally arranged phased array antennas realize spatial beam scanning in the range of (-65° - 0°).

[0080] Referring toFigure 15 , Figure 15 is a schematic structural diagram of the fourth embodiment of the phased array antenna of the present invention. As Figure 15 shown, in this embodiment, the phased array antenna is a two-dimensional parallel-fed phased array antenna, and the antenna includes: the multi-branch antenna elements arranged in an M*M rectangle; the phased array antenna further includes: a one-to-M power divider, a single-pole double-throw switch, and a T / R component; Figure 16 is a schematic diagram of the distribution of the feeding ports of the fourth embodiment of the phased array antenna of the present invention. In this embodiment, a two-dimensional 8*8 element parallel-fed phased array antenna is taken as an example for illustration, and the power divider adopts a one-to-eight power divider.

[0081] As Figure 16 shown, there are 16 columns of feeding ports arranged along the x direction of the 8*8 array antenna, and each column has 8 feeding ports. There are 8 rows of feeding ports arranged along the y direction. As Figure 15 shown, each column of feeding ports arranged along the x direction of the two-dimensional parallel-fed phased array antenna is combined by a one-to-eight power divider (③) to form the input ports of 16 power dividers (③). The input ports of the 16 power dividers (③) are respectively labeled as A1 to A16. Among the input ports (A1 to A16) of these 16 power dividers (③), the output ports of the single-pole double-throw switch are used to connect every two adjacent input ports. A total of 8 single-pole double-throw switches are required. The input ends of the single-pole double-throw switch are composed of a D group of ports (the D group of ports consists of 8 ports from port D1 to D8) and an E group of ports (the E group of ports consists of 8 ports from port E1 to E8). The single-pole double-throw switch is switched to connect the E group of ports or the D group of ports. The input ends of these 8 single-pole double-throw switches are connected to the output ends of 8 T / R components. The input ends of the 8 T / R components are connected to the output end of a one-to-eight power divider (④). When feeding the input end of the one-to-eight power divider (④), the T / R component only needs to provide amplitude-phase control for a sub-scanning area and can realize beam scanning in the yoz plane (-65° to 65°) by switching different feeding ports of the antenna element through the single-pole double-throw switch. Specifically, when feeding the input end of the one-to-eight power divider (④) and simultaneously turning all the single-pole double-throw switches to the left to connect the D group of ports (the D group of ports consists of 8 ports from port D1 to D8), the 8*8 two-dimensional arranged phased array antenna realizes spatial beam scanning of (0° - 65°); when simultaneously turning all the single-pole double-throw switches to the right to connect the E group of ports (the E group of ports consists of 8 ports from port E1 to E8), the 8*8 two-dimensional arranged phased array antenna realizes spatial beam scanning of (-65° - 0°).

[0082] Figure 17 is the beam scanning direction pattern of the first and third embodiments of the phased array antenna of the present invention, Figure 18 is the beam scanning direction pattern of the second and fourth embodiments of the phased array antenna of the present invention. AsFigure 17 As shown, in the first and third embodiments of the phased array antenna of the present invention, within the scanning range of ±65°, the maximum gain is 13.1 dBi, the minimum gain is 12.7 dBi, and the gain drop is less than 2 dBi, enabling flat scanning gain. As Figure 18 shown, in the second and fourth embodiments of the phased array antenna of the present invention, within the scanning range of ±65°, the maximum gain is 21.1 dBi, the minimum gain is 19.1 dBi (when scanned to ±65°), and the gain drop is less than 2 dBi, enabling flat scanning gain. At the same time, the one-dimensional scanning phased array antenna described in the present invention can also be combined with a turntable to form an electromechanical hybrid two-dimensional phased array antenna system with pitch and azimuth two-dimensional scanning functions.

[0083] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

[0084] Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0085] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0086] In addition, the descriptions involving "first", "second", etc. in the present invention are only for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

Claims

1. A multi-branch antenna unit, characterized in that, The multi-branch antenna unit includes: a multi-branch radiation structure and a feeding structure; The multi-branch radiation structure includes: the first to third flat plates symmetrically arranged, and adjacent two flat plates respectively form the first to second branches; The feeding structure includes: a rectangular metal cavity, a dielectric substrate, a first port, a second port, two feeding probes and a microstrip line; The first port and the second port are symmetrically arranged at the bottom of the feeding structure, and the first port and the second port are respectively connected to both ends of the microstrip line through the feeding probes; The dielectric substrate is arranged in the rectangular metal cavity, and the multi-branch radiation structure is arranged above the rectangular metal cavity; An external feeding power source excites the microstrip line through the first port or the second port, forms an electromagnetic field and then feeds it into the multi-branch radiation structure to form a radiation beam; The dielectric substrate includes, from bottom to top: a first dielectric layer and a second dielectric layer; The first port and the second port are arranged at the bottom of the first dielectric layer, both of the two feeding probes are arranged inside the first dielectric layer, and the microstrip line is arranged at the interface between the first dielectric layer and the second dielectric layer.

2. The multi-branch antenna unit according to claim 1, wherein The first dielectric layer and the second dielectric layer have the same thickness.

3. The multi-branch antenna unit according to claim 2, wherein, In the multi-branch radiation structure, the first flat plate and the third flat plate symmetrically arranged are set at the same first preset height, the second flat plate is set at a second preset height, and the first to third flat plates are set at the same first preset thickness; The first flat plate and the second flat plate form the first branch, and the second flat plate and the third flat plate form the second branch; The first branch and the second branch have the same first preset spacing.

4. The multi-branch antenna unit according to claim 3, characterized in that, The pointing and width of the radiation beam are adjusted according to the first preset height, the second preset height, the first preset thickness and the first preset spacing.

5. The multi-branch antenna unit according to claim 4, characterized in that, The height of the rectangular metal cavity is twice the thickness of the first dielectric layer.

6. A phased array antenna, characterized in that, The phased array antenna includes a plurality of multi-branch antenna units as described in any one of claims 1 to 5 and T / R components corresponding to the number of the multi-branch antenna units.

7. The phased array antenna according to claim 6, characterized in that, The phased array antenna includes: N multi-branch antenna units arranged in one dimension, where N is an integer greater than 1; Adjacent multi-branch antenna units are connected in series-feed through the T / R components.

8. The phased array antenna according to claim 6, wherein, The phased array antenna includes: M*M multi-branch antenna units arranged in a rectangular array, where M is an integer greater than 1; The phased array antenna further includes: a one-to-M power divider; On one direction of the rectangular array, the multi-branch antenna units are combined through the one-to-M power divider to form 2M input ports of the one-to-M power divider; For the 2M one-to-M power dividers, except for the first and the last one, the input ports of the remaining adjacent one-to-M power dividers are connected in series-feed through the T / R components.

9. The phased array antenna according to claim 6, characterized in that, The phased array antenna includes: N multi-branch antenna units arranged in one dimension, where N is an integer greater than 1, and adjacent multi-branch antenna units are arranged in parallel-feed; The phased array antenna further includes: a one-to-N power divider and N single-pole double-throw switches; The input ends of the T / R components are connected to the output ports of the one-to-N power divider, and the output ends of the T / R components are connected to the input ends of one of the single-pole double-throw switches. The two output ends of each single-pole double-throw switch are respectively connected to the first port and the second port of the corresponding multi-branch antenna unit.

10. The phased array antenna according to claim 6, wherein, The phased array antenna includes: the multi-branch antenna units arranged in an M*M rectangle; The phased array antenna further includes: a one-to-M power divider and a single-pole double-throw switch; On one direction of the rectangle array, the multi-branch antenna units are combined through the one-to-M power divider to form 2M input ports of the one-to-M power dividers; The input ports of adjacent one-to-M power dividers are connected through the two output ports of the single-pole double-throw switch, and the input end of the single-pole double-throw switch is connected to the output end of the corresponding T / R component.

Images