C-band phased-array antenna

Abstract

The invention discloses a C-band phased-array antenna which comprises a mounting seat and an antenna body, and the antenna body is arranged on the mounting seat. The antenna body comprises a plurality of linear array structures, and the plurality of linear array structures are sequentially arranged in the vertical direction; the linear array structure comprises a waveguide power division unit and a plurality of horn units, the horn units are sequentially arranged in the transverse direction, the horn units are communicated with the waveguide power division unit, and the waveguide power division unit is used for distributing input electromagnetic wave power to the horn units. The multiple linear array structures are sequentially arranged in the vertical direction to form the array, the structure is simple, and the feed structure is convenient to design; each linear array structure further comprises a waveguide power division unit and a plurality of horn units, electromagnetic wave power is output to each horn unit through the waveguide power division unit and then is output by the horn units, the frequency band is wide, the side lobe is small, and the gain is higher.

Description

Technical Field

[0001] The present application relates to the field of antenna technology, and in particular to a C-band phased array antenna. Background Art

[0002] The frequency bands used in satellite communications include L, S, C, Ku, Ka, etc. The most commonly used frequency bands are C (4-8GHz) and Ku (12-18Ghz) bands. C-band antennas refer to antennas with an operating frequency band of 4-8GHz. Commercial communication satellites start from the C band. Antennas are classified according to their appearance into diamond antennas, loop antennas, spiral antennas, waveguide mouth antennas, waveguide slot antennas, Yagi antennas, horn antennas and reflector antennas. Existing C-band antennas generally use Yagi antennas or reflector antennas as prototypes. Existing C-band antennas have complex structures, difficult feeding structures to design, narrow frequency bands, and low gain. Summary of the invention

[0003] The main technical problem solved by the present application is to provide a C-band phased array antenna to solve the problems of the existing C-band antenna having a complex structure, a difficult feeding structure to design, a narrow frequency band and a low gain.

[0004] In order to solve the above technical problems, a technical solution adopted in the present application is to provide a C-band phased array antenna, including a mounting base and an antenna body, and the antenna body is arranged on the mounting base; the antenna body includes multiple linear array structures, and the multiple linear array structures are arranged in sequence along the vertical direction; the linear array structure includes a waveguide power division unit and multiple speaker units, and the multiple speaker units are arranged in sequence along the horizontal direction. The multiple speaker units are connected to the waveguide power division unit, and the waveguide power division unit is used to distribute the input electromagnetic wave power to each speaker unit.

[0005] In some embodiments, the speaker unit has a first bell mouth at one end away from the waveguide power splitter unit, the length of the first bell mouth is 40mm-45mm, and the height is 40mm-45mm. The speaker unit has a second bell mouth at one end adjacent to the waveguide power splitter unit, the length of the second bell mouth is 38mm-43mm, and the height is 20mm-25mm. The spacing between the center points of adjacent first bell mouths is 40mm-45mm.

[0006] In some embodiments, the waveguide power splitter unit has a waveguide opening at one end away from the speaker unit, and the length of the waveguide opening is 38mm-43mm and the height is 20mm-25mm.

[0007] In some embodiments, the antenna body has a length of 630mm-640mm, a width of 300mm-310mm, and a height of 360mm-370mm.

[0008] In some embodiments, the number of the linear array structures is 8, and each linear array structure includes 14 speaker units.

[0009] In some embodiments, the linear array structure includes a first linear array mounting plate and a second linear array mounting plate. The first linear array mounting plate and the second linear array mounting plate have the same structure. The first linear array mounting plate and the second linear array mounting plate are mirror-symmetrically arranged along the vertical direction. The first linear array mounting plate and the second linear array mounting plate are detachably connected.

[0010] In some embodiments, both the first linear array mounting plate and the second linear array mounting plate are provided with connecting grooves, and the connecting grooves on the first linear array mounting plate and the connecting grooves on the second linear array mounting plate together enclose a waveguide power splitter unit and a speaker unit.

[0011] In some embodiments, the waveguide power splitter unit includes a main waveguide and multiple branch waveguides. The main waveguide is connected to the waveguide port, and the main waveguide is also connected to multiple branch waveguides respectively. The main waveguide is used to distribute the electromagnetic wave power input from the waveguide port to each branch waveguide, and the branch waveguides are connected to the speaker unit accordingly.

[0012] In some embodiments, the main waveguide includes a first branch waveguide, a second branch waveguide, a third branch waveguide, a fourth branch waveguide, a fifth branch waveguide, a sixth branch waveguide and a seventh branch waveguide, the branch waveguide includes a first sub-branch waveguide and a second sub-branch waveguide, the first branch waveguide is connected to the waveguide mouth, the two ends of the first branch waveguide are respectively connected to two second branch waveguides, the two ends of each second branch waveguide are connected to the third branch waveguide and the fourth branch waveguide, the third branch waveguide connects the fifth branch waveguide and the sixth branch waveguide, the fourth branch waveguide connects the seventh branch waveguide and a first sub-branch waveguide, the two ends of the fifth branch waveguide, the sixth branch waveguide and the seventh branch waveguide are respectively connected to a second sub-branch waveguide, the first sub-branch waveguide and the second sub-branch waveguide are each connected to a speaker unit; the waveguide power division unit is symmetrical with respect to the center line of the length direction of the first branch waveguide, and the first sub-branch waveguide is adjacent to the center line of the length direction of the first branch waveguide.

[0013] In some embodiments, the antenna body is disposed on the mounting base at an elevation angle of 30°-35°.

[0014] The beneficial effects of the present application are as follows: the present application discloses a C-band phased array antenna, which includes a mounting base and an antenna body, and the antenna body is arranged on the mounting base; the antenna body includes a plurality of linear array structures, and the plurality of linear array structures are arranged in sequence along the vertical direction; the linear array structure includes a waveguide power division unit and a plurality of speaker units, and the plurality of speaker units are arranged in sequence along the horizontal direction, and the plurality of speaker units are connected to the waveguide power division unit, and the waveguide power division unit is used to distribute the input electromagnetic wave power to each speaker unit. By arranging a plurality of linear array structures in sequence along the vertical direction to form an array, the structure is simple, and the feeding structure is easy to design; each linear array structure includes a waveguide power division unit and a plurality of speaker units, and the electromagnetic wave power is output to each speaker unit through the waveguide power division unit, and then output by the speaker unit, with a wide frequency band, small side lobes, and higher gain. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of an embodiment of the present application;

[0016] Figure 2 It is a schematic diagram of the exploded structure of a mounting base according to an embodiment of the present application;

[0017] Figure 3 It is a structural schematic diagram of an antenna body according to an embodiment of the present application;

[0018] Figure 4 is a structural schematic diagram of the antenna body of one embodiment of the present application from another perspective;

[0019] Figure 5 is a schematic structural diagram of a first array mounting frame according to an embodiment of the present application;

[0020] Figure 6 It is a schematic diagram of the structure of a waveguide power splitter unit and a speaker unit according to an embodiment of the present application;

[0021] Figure 7 is a schematic diagram of a basic model and a coordinate system of an embodiment of the present application;

[0022] Figure 8 is a schematic diagram of an EIRP requirement curve of a C-band phased array antenna according to an embodiment of the present application;

[0023] Fig. 9 is the return loss of the C-band phased array speaker unit in one embodiment of the present application;

[0024] Fig.10 is the E-plane radiation pattern of the C-band phased array speaker unit in one embodiment of the present application;

[0025] Fig.11 is the H-plane radiation pattern of the C-band phased array speaker unit in one embodiment of the present application;

[0026] Fig.12 is the polarization isolation of the E-plane of the C-band phased array speaker unit in one embodiment of the present application;

[0027] Fig.13 is the polarization isolation of the H plane of the C-band phased array speaker unit in one embodiment of the present application;

[0028] Fig.14 It is the azimuth linear array pattern of the C-band phased array in one embodiment of the present application;

[0029] Fig.15 is the unit isolation of the azimuth linear array of the C-band phased array in one embodiment of the present application;

[0030] Fig.16 is the return loss of the total return port of the C-band phased array waveguide power divider in one embodiment of the present application;

[0031] Fig.17 This is a simulation result diagram of the amplitude of a C-band phased array waveguide power division unit according to an embodiment of the present application;

[0032] Fig.18 This is a simulation result diagram of the phase of a C-band phased array waveguide power division unit according to an embodiment of the present application;

[0033] Fig.19 is the return loss of the C-band phased array azimuth linear array in one embodiment of the present application;

[0034] Fig. 20 is the directional diagram of the C-band phased array azimuth linear array in one embodiment of the present application;

[0035] Fig.21 This is an electric field distribution diagram of the C-band phased array azimuth linear array aperture in one embodiment of the present application;

[0036] Fig. 22 is a 3D pattern of a C-band phased array antenna beam pointing to 0° in an embodiment of the present application;

[0037] Fig.23 It is the 3D radiation pattern when the C-band phased array antenna beam points to theta+40° in one embodiment of the present application;

[0038] Fig.24 This is the elevation pattern when the C-band phased array antenna beam points to 0° in one embodiment of the present application;

[0039] Fig.25 is the polarization isolation in the elevation plane when the C-band phased array antenna beam points to 0° in one embodiment of the present application;

[0040] Fig.26 It is the azimuth plane pattern when the C-band phased array antenna beam points to 0° in one embodiment of the present application;

[0041] Fig. 27 is the polarization isolation in the azimuth plane when the C-band phased array antenna beam points to 0° in one embodiment of the present application;

[0042] Fig.28 This is the elevation pattern of the C-band phased array antenna when the beam is pointed at 40° in one embodiment of the present application;

[0043] Fig.29 It is the polarization isolation of the elevation plane when the C-band phased array antenna beam points to 40° in one embodiment of the present application;

[0044] Fig.30 This is the azimuth plane pattern when the C-band phased array antenna beam points to 40° in one embodiment of the present application;

[0045] Fig.31 It is the polarization isolation in the azimuth plane when the C-band phased array antenna beam points to 40° in one embodiment of the present application;

[0046] Fig.32 It is the aperture electric field distribution of the C-band phased array antenna at 5.25 GHz in one embodiment of the present application;

[0047] Fig.33 The electric field distribution of the C-band phased array antenna at 5.5 GHz in one embodiment of the present application;

[0048] Fig.34 The electric field distribution of the C-band phased array antenna at 5.75 GHz in one embodiment of the present application;

[0049] Fig.35 It is the port isolation of the C-band phased array antenna in one embodiment of the present application. DETAILED DESCRIPTION

[0050] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of this application.

[0051] It should be noted that when an element is referred to as being "fixed on" or "set on" another component, it can be directly on the other component or indirectly set on the other component; when a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component.

[0052] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "vertical", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0053] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" and "several" mean two or more, unless otherwise clearly and specifically defined.

[0054] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so that people familiar with this technology can understand and read them. They are not used to limit the conditions under which this application can be implemented, so they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in this application without affecting the effects and purposes that can be achieved by this application.

[0055] For the description of this application, non-limiting Figure 1 The marks "front", "rear", "up", "down", "left" and "right" shown in the figure are used to facilitate understanding of the embodiment and are not intended to limit the present application. Among them, the front-to-back direction represents the longitudinal direction, the left-to-right direction represents the transverse direction, and the up-down direction represents the vertical direction.

[0056] Figure 1-Figure 6 An embodiment of a C-band phased array antenna of the present application is shown, comprising a mounting base 1 and an antenna body 2, wherein the antenna body 2 is disposed on the mounting base 1; the antenna body 2 comprises a plurality of linear array structures 20, wherein the plurality of linear array structures 20 are arranged in sequence along a vertical direction; the linear array structure 20 comprises a waveguide power division unit 21 and a plurality of speaker units 22, wherein the plurality of speaker units 22 are arranged in sequence along a horizontal direction, and the plurality of speaker units 22 are connected to the waveguide power division unit 21, and the waveguide power division unit 21 is used to distribute the input electromagnetic wave power to each speaker unit 22.

[0057] The present application forms an array by arranging multiple linear array structures 20 in sequence along the vertical direction, which has a simple structure and convenient feeding structure design; each linear array structure 20 includes a waveguide power division unit 21 and multiple speaker units 22, and the electromagnetic wave power is output to each speaker unit 22 through the waveguide power division unit 21, and then output by the speaker unit 22, with a wide frequency band, small side lobes and higher gain.

[0058] In some embodiments, in combination Figure 3 , Figure 4 and Figure 6 As shown, the speaker unit 22 has a first trumpet mouth 221 at one end away from the waveguide power splitter unit 21, the first trumpet mouth 221 is rectangular, the length of the first trumpet mouth 221 is 40mm-45mm, for example, 40mm, 41.5mm or 44.4mm, and the height is 40mm-45mm, for example, 42mm, 43mm or 44.4mm. The speaker unit 22 has a second trumpet mouth 222 at one end adjacent to the waveguide power splitter unit 21, the second trumpet mouth 222 is rectangular, the length of the second trumpet mouth 222 is 38mm-43mm, for example, 38mm, 40.4mm or 41.5mm, and the height is 20mm-25mm, for example, 20.2mm, 23mm or 24.5mm, and the spacing between the center points of adjacent first trumpet mouths 221 is 40mm-45mm, for example, 41.5mm, 43mm or 44.4mm.

[0059] The present application reasonably designs the aperture sizes of the first bell mouth 221 and the second bell mouth 222 of the speaker unit 22 and the spacing between each speaker unit 22, thereby not only ensuring sufficient side lobe margin, but also reducing the mutual coupling effect between units and achieving high aperture efficiency.

[0060] Specifically, the length of the first bell mouth 221 is 44.4 mm, and the height is 44.4 mm; the length of the second bell mouth 222 is 40.4 mm, and the height is 20.2 mm; and the distance between the center points of adjacent first bell mouths 221 is 44.4 mm.

[0061] In some embodiments, Figure 1 As shown, the antenna body 2 is arranged on the mounting base 1 at an elevation angle of 30°-35°. The elevation angle can be 31°, 32° or 33°, etc. Specifically in this embodiment, the elevation angle is 33° to ensure the best signal quality and coverage range.

[0062] In some embodiments, in combination Figure 1 and Figure 2As shown, the mounting base 1 includes a base plate 11, a connecting bracket 12, a fixed shaft 13, a bearing 14, a shaft end top cover 15, a rotating sleeve 16, a first gear 17, a second gear 18 and a driving motor. The fixed shaft 13 is arranged on the base plate 11, the bearing 14 is sleeved on the outside of the fixed shaft 13, and the bearing 14 can rotate relative to the fixed shaft 13. The shaft end top cover 15 is connected to the upper end of the fixed shaft 13, and the shaft end top cover 15 is in conflict with the bearing 14. The rotating sleeve 16 is arranged on the periphery of the bearing 14, and the rotating sleeve 16 is connected to the connecting bracket 12. The antenna body 2 is arranged on the connecting bracket 12, the first gear 17 is sleeved on the periphery of the rotating sleeve 16, and the rotating sleeve 16 can rotate with the first gear 17, and the first gear 17 is meshed with the second gear 18. The driving motor is arranged on the connecting bracket 12, and the driving motor is connected to the second gear 18. The driving motor is used to drive the second gear 18 to rotate. The second gear 18 is driven to rotate by a driving motor, the second gear 18 is meshed with the first gear 17, the first gear 17 also rotates synchronously, the rotating sleeve 16 and the bearing 14 synchronously follow the rotation of the first gear 17 and rotate relative to the fixed shaft 13, the rotating sleeve 16 is connected to the connecting bracket 12, driving the rotation of the connecting bracket 12, the antenna body 2 is arranged on the connecting bracket 12, so that the antenna body 2 is adjusted by rotating the connecting bracket 12, so that the antenna body 2 is more flexible, and the rotation function increases the airspace range that the antenna body 2 can cover.

[0063] In some embodiments, in combination Figure 4 and Figure 6 As shown, the end of the waveguide power splitter unit 21 away from the speaker unit 22 has a waveguide port 211, the waveguide port 211 is rectangular, the length of the waveguide port 211 is 38mm-43mm, for example, 39mm, 40.4mm or 42.5mm; the height is 20mm-25mm, for example, 20.2mm, 21.5mm or 24.5mm. Specifically, the length of the waveguide port 211 is 40.4mm, and the height is 20.2mm. The electromagnetic wave power input from the waveguide port 211 is finally output from the first horn port 221 of the speaker unit 22, and the return loss of the speaker unit 22 in the working frequency band is better than 14dB.

[0064] In some embodiments, the length of the antenna body 2 is 630mm-640mm, such as 630mm, 635mm or 640mm, the width is 300mm-310mm, such as 300mm, 302mm or 307mm, and the height is 360mm-370mm, such as 360mm, 363mm or 370mm. Specifically, the length of the antenna body 2 is 630mm, the width is 300mm, the height is 360mm, the number of linear array structures 20 is 8, and each linear array structure 20 includes 14 speaker units 22. The number of linear array structures 20 and speaker units 22 is optimized, which has the advantages of high aperture efficiency and more reasonable gain.

[0065] In some embodiments, the antenna body 2 is an integrated structure or is formed by combining multiple structures.

[0066] In some embodiments, in combination Figure 3 and Figure 5 As shown, the linear array structure 20 includes a first linear array mounting plate 201 and a second linear array mounting plate 202. The first linear array mounting plate 201 and the second linear array mounting plate 202 have the same structure. The first linear array mounting plate 201 and the second linear array mounting plate 202 are mirror-symmetrically arranged along the vertical direction. The first linear array mounting plate 201 and the second linear array mounting plate 202 are detachably connected, and specifically can be spliced ​​or connected by bolts. In this embodiment, a splicing method is adopted, and a completed linear array structure 20 is formed by combining and splicing the first linear array mounting plate 201 and the second linear array mounting plate 202, and then a plurality of linear array structures 20 are combined and spliced ​​to form an antenna body 2, which is convenient for transportation and installation.

[0067] In some embodiments, in combination Figure 3 , Figure 5 and Figure 6 As shown, both the first linear array mounting plate 201 and the second linear array mounting plate 202 are provided with a connecting groove 2011, and the connecting groove 2011 on the first linear array mounting plate 201 and the connecting groove 2011 on the second linear array mounting plate 202 are enclosed together to form the waveguide power splitter unit 21 and the speaker unit 22. By providing the connecting groove 2011 on the first linear array mounting plate 201 and the second linear array mounting plate 202, and forming the waveguide power splitter unit 21 and the speaker unit 22 by docking the connecting grooves 2011, it is convenient for mass production of the first linear array mounting plate 201 and the second linear array mounting plate 202, and the docking effect is also better.

[0068] In some embodiments, Figure 6 As shown, the waveguide power splitter unit 21 includes a main waveguide 212 and a plurality of branch waveguides 213. The main waveguide 212 is connected to the waveguide port 211. The main waveguide 212 is also respectively connected to a plurality of branch waveguides 213. The main waveguide 212 is used to distribute the electromagnetic wave power input from the waveguide port 211 to each branch waveguide 213. The branch waveguide 213 is correspondingly connected to the speaker unit 22. Electromagnetic power is input through each waveguide port 211, and the electromagnetic power is transmitted to each branch waveguide 213 after passing through the main waveguide 212. Each branch waveguide 213 is connected to the speaker unit 22, and the electromagnetic power is output from the speaker unit 22, with good isolation effect and extremely low loss.

[0069] Specifically, in some embodiments, Figure 6As shown, the main waveguide 212 includes a first branch waveguide 2121, a second branch waveguide 2122, a third branch waveguide 2123, a fourth branch waveguide 2124, a fifth branch waveguide 2125, a sixth branch waveguide 2126 and a seventh branch waveguide 2127, the branch waveguide 213 includes a first sub-branch waveguide 2131 and a second sub-branch waveguide 2132, the first branch waveguide 2121 is connected to the waveguide port 211, the two ends of the first branch waveguide 2121 are respectively connected to two second branch waveguides 2122, the two ends of each second branch waveguide 2122 are connected to the third branch waveguide 2123 and the fourth branch waveguide 2124, the third branch waveguide 2123 is connected to the waveguide port 211, and the second branch waveguide 2122 is connected to the third branch waveguide 2123 and the fourth branch waveguide 2124. The fifth branch waveguide 2125 and the sixth branch waveguide 2126 are connected, the fourth branch waveguide 2124 is connected to the seventh branch waveguide 2127 and a first sub-branch waveguide 2131, the fifth branch waveguide 2125, the sixth branch waveguide 2126 and the seventh branch waveguide 2127 are connected to a second sub-branch waveguide 2132 at both ends, and the first sub-branch waveguide 2131 and the second sub-branch waveguide 2132 are respectively connected to a speaker unit 22; the waveguide power splitter unit 21 is symmetrical with respect to the center line 210 of the length direction of the first branch waveguide 2121, and the first sub-branch waveguide 2131 is adjacent to the center line 210 of the length direction of the first branch waveguide 2121. The total port return loss of the waveguide power splitter unit 21 in the working frequency band is better than 14dB.

[0070] The above is an introduction to the specific structure of the C-band phased array antenna. The following is an introduction to the design principle and working performance of the C-band phased array antenna.

[0071] First, the system requirements of the C-band phased array antenna are clarified, as shown in Table 1.

[0072] Table 1 System requirements for C-band phased array antenna

[0073] Frequency band type C pulse Frequency range (GHz) VSWR ＜2.0 Passive antenna gain (dBi) >26dBi Polarization Vertical polarization Horizontal spatial coverage (deg) ±60 degrees (mechanical turntable) Vertical spatial coverage (deg) Elevation angle 4~62deg (phase control) Mechanical turntable angle accuracy (deg) ≤0.1 Electronic scanning angle error (deg) ≤1 Horizontal side lobe (dBC) ≥20 Elevation sidelobe (dBC) ≥12 Horizontal beam width (deg) 4～6 Elevation beam width (deg) 4～6 EIRP Limit (dBW) ≥67 Beam switching speed (us) ≤100(configurable)

[0074] Then establish the basic model and coordinate system, combined with Figure 7 As shown, the rectangular coordinate system is defined as follows:

[0075] Origin: located at the center of the antenna 10. If it is a speaker array, it is at the center of the speaker array aperture.

[0076] OZ axis direction: the plane on the vertical platform (parallel to the ground) points to the zenith;

[0077] OX axis direction: The OXZ plane passes through the maximum radiation point of the antenna, the OX axis is perpendicular to the OZ axis and parallel to the ground plane;

[0078] OY axis direction: perpendicular to OX axis and OZ axis, and forming a right-hand spiral relationship;

[0079] The polar coordinate system is as follows:

[0080] Direction: A straight line away from the origin pointing to any space, along The coordinates of the point ball in the direction only have the r component gain, and the components in other directions remain unchanged;

[0081] Direction: The θ unit gain direction of a point in the airspace, along The spherical coordinates of the point in the direction only have the θ component gain, and the other directional components remain unchanged. The θ angle at the point is defined as the angle between the line connecting the point and the origin and the OZ axis, and its value space is [0,π];

[0082] Direction: A point in the airspace Unity gain direction, along The point coordinates in the direction are only Component gain, other direction components remain unchanged; The angle is defined as the angle between the projection of the point on the XOY plane and the OX axis, and its value space is [0,2π];

[0083] In the above defined coordinate system, the EIRP requirement of the C-band is plotted as a graph. The EIRP requirement curve 30 of the C-band phased array antenna is as follows: Figure 8 As shown. The electronic scanning coverage space of the C-band phased array antenna is θ∈[x°,x+50°], The θ angle plane is the space covered by the electronic scanning. The airspace is 3dB beam width. y∈[-60°,60°] is the mechanical angle adjustment range of the phased array in the horizontal direction. The actual single beam coverage airspace is not less than 4-6 degrees in pitch and 4-6 degrees in horizontal.

[0084] Phased array antennas can change the beam direction by changing the unit phase in the array antenna. Compared with mechanical rotating antennas, they have faster response speeds, more flexible beam switching capabilities, and can better lock and track targets. Therefore, this antenna solution uses a phased array.

[0085] According to the index requirements of this antenna, the antenna is designed as a one-dimensional phased array. The antenna array adopts a horn antenna array, which has the advantages of high power resistance and stable structure. The antenna is a fixed beam in the azimuth plane, and a certain weighted amplitude distribution is adopted to achieve low side lobes; multiple exits are set on the elevation plane for connecting RF components to achieve phased scanning.

[0086] The unit length and spacing in the azimuth direction (i.e., the lateral direction) must be optimized to simultaneously meet the requirements of beam width, gain, and sidelobe level. To ensure gain, the beam width should not be too wide. If the unit length is too long or the unit spacing is too large, the number of units must be reduced, resulting in low aperture efficiency and insufficient sidelobe margin; otherwise, the mutual coupling between units is strong, and the aperture efficiency decreases significantly during beam scanning.

[0087] In order to meet the beam width and gain requirements in the pitch direction (i.e., vertical direction), the number of paths in the pitch direction should not be too small, otherwise the grating lobe after beam scanning will be too high and the gain will drop significantly; otherwise, the beam width will be too narrow due to excessive gain, the cost of RF components will increase and it will cause inconvenience when installing the antenna.

[0088] After calculation and optimization, the antenna finally selected is an 8*14 array with a unit spacing of 44.4mm. A waveguide power division structure is used to perform amplitude-weighted feeding on the 14 units. The polarization is along the pitch direction, and there are 8 phased arrays in the pitch direction, which can achieve ±29 degree beam scanning.

[0089] like Fig. 9 The figure shows the return loss of the C-band phased array speaker unit. The horizontal axis is the frequency band and the vertical axis is the return loss. Fig. 9 It can be seen that the return loss of the speaker unit within the working frequency band is better than 14dB.

[0090] like Fig.10 The E-plane radiation pattern of the C-band phased array speaker unit is shown in the figure. The horizontal axis is the beam width and the vertical axis is the gain. Fig.10 It can be seen that the gain of the speaker unit reaches 8.6dBi and the E-plane beamwidth is about 62°.

[0091] like Fig.11 The H-plane radiation pattern of the C-band phased array speaker unit is shown in Figure 1. Fig.11 It can be seen that the gain of the speaker unit reaches 8.6dBi and the H-plane beamwidth is about 69°.

[0092] like Fig.12 The figure shows the polarization isolation of the E-plane of the C-band phased array speaker unit. Fig.13 The figure shows the polarization isolation of the H plane of the C-band phased array speaker unit. Fig.12 and Fig.13 It can be seen that the polarization isolation of the speaker unit within the main lobe range is above 45dB.

[0093] like Fig.14The figure shows the C-band phased array azimuth line array pattern. After optimization, the normalized power of each speaker unit is set to -11dB, -8dB, -5dB, -3dB, -1.5dB, -0.5dB, 0dB, 0dB, -0.5dB, -1.5dB, -3dB, -5dB, -8dB, -11dB, with the same phase, and the beam width reaches 5.1°, and the sidelobe level is lower than -30dB, which meets the index requirements and has a certain margin.

[0094] like Fig.15 The figure shows the unit isolation of the C-band phased array azimuth linear array. It can be seen from the figure that the unit isolation of the azimuth linear array is above 25dB.

[0095] The waveguide power splitter units are distributed symmetrically, such as Fig.16 As shown in the figure, it is the return loss of the total return port of the C-band phased array waveguide power divider. It can be seen from the figure that the total return loss of the waveguide power divider unit in the working frequency band is better than 14dB.

[0096] The amplitude and phase of the waveguide power splitter are simulated as follows: Fig.17 and Fig.18 As shown, Fig.17 is the simulation result of the amplitude of the C-band phased array waveguide power division unit, Fig.18 The simulation results of the phase of the C-band phased array waveguide power splitter. The power ratio of each port basically meets the design requirements. Due to the structural layout, the phase difference of each port is between 25° and 44°.

[0097] The waveguide power division unit and the speaker unit are formed inside the linear array structure, such as Fig.19 The figure shows the return loss of the C-band phased array azimuth line array. Fig.19 It can be seen that the total return loss of the azimuth linear array is better than 10.7dB. Fig. 20 This is the radiation pattern of the C-band phased array azimuth linear array. The beamwidth of the azimuth linear array at each frequency point reaches 5.2°, the gain reaches 19.8dBi, and the sidelobe level reaches -25dB, which meets the design indicators.

[0098] like Fig.21 The figure shows the electric field distribution of the C-band phased array azimuth linear array aperture. It can be seen from the figure that the electric field intensity of each unit aperture basically meets the design power ratio.

[0099] like Fig. 22 The figure shows the 3D radiation pattern of the C-band phased array antenna when the beam is pointed at 0°. Fig.23 The 3D radiation pattern of the C-band phased array antenna when the beam is pointed at theta+40° is shown. Fig. 22 and Fig.23It can be seen that the antenna can achieve good beam transformation, and the grating lobe appears at theta-30°, which is outside the sensitive area and does not affect the system performance.

[0100] like Fig.24 The figure shows the elevation pattern of the C-band phased array antenna when the beam is pointed at 0°. Fig.25 The figure shows the polarization isolation in the elevation plane when the C-band phased array antenna beam is pointed at 0°. Fig.24 and Fig.25 It can be seen that when the beam is pointed at 0°, the beam width of the total array at each frequency point on the pitch plane reaches 5.0°, the gain reaches 30dBi, the sidelobe level is lower than -25dB, the polarization purity in the main lobe range is above 55dB, and the front-to-back ratio reaches 30dB.

[0101] like Fig.26 The figure shows the azimuth pattern of the C-band phased array antenna when the beam is pointing to 0°. Fig. 27 The figure shows the polarization isolation in the azimuth plane when the C-band phased array antenna beam points to 0°. Fig.26 and Fig. 27 It can be seen that when the beam points to 0°, the beam width of the total array at each frequency point in the azimuth plane reaches 5.0°, the gain reaches 30dBi, the sidelobe level is lower than -25dB, the polarization purity in the main lobe range is above 55dB, and the front-to-back ratio reaches 30dB.

[0102] like Fig.28 The figure shows the elevation pattern of the C-band phased array antenna when the beam is pointed at 40°. Fig.29 The figure shows the polarization isolation in the elevation plane when the C-band phased array antenna beam points to 40°. Fig.28 and Fig.29 It can be seen that when the beam is pointed at 40°, the beam width of the total array at each frequency point in the pitch plane reaches 6.2°, the gain reaches 26dBi, the sidelobe level is lower than -25dB, the grating lobe is outside the sensitive area, the polarization purity in the main lobe range is above 55dB, and the front-to-back ratio reaches 30dB.

[0103] like Fig.30 The figure shows the azimuth pattern of the C-band phased array antenna when the beam is pointed at 40°. Fig.31 The figure shows the polarization isolation in the azimuth plane when the C-band phased array antenna beam points to 40°. Fig.30 and Fig.31 It can be seen that when the beam is pointed at 40°, the beam width of the total array at each frequency point in the azimuth plane reaches 7.9°, the gain reaches 26dBi, the sidelobe level is lower than -25dB, and the polarization purity in the main lobe range is above 40dB.

[0104] like Figure 32-Figure 34The following are the electric field distributions of the C-band phased array antenna at 5.25 GHz, 5.5 GHz and 5.75 GHz. Figure 32-Figure 34 It can be seen that the electric field strength is high in the middle and low on both sides, which is basically consistent with the designed power ratio. The phase consistency of each unit deviates greatly from the design, but the overall sidelobe level is still within the specification range.

[0105] like Fig.35 The figure shows the port isolation of the C-band phased array antenna. As can be seen from Figure 35, the isolation of each port of the antenna is above 16dB.

[0106] In summary, the C-band phased array antenna adopts a horn array form, with a design frequency band of 5.25-5.75 GHz and vertical linear polarization. Within the beam scanning range, the gain of each frequency point reaches 26 dBi, the beam width is basically 4°-6°, and the sidelobe level is lower than -24 dB, meeting the design index requirements.

[0107] It can be seen that the present application discloses a C-band phased array antenna, which includes a mounting base and an antenna body, and the antenna body is arranged on the mounting base; the antenna body includes a plurality of linear array structures, and the plurality of linear array structures are arranged in sequence along the vertical direction; the linear array structure includes a waveguide power division unit and a plurality of speaker units, and the plurality of speaker units are arranged in sequence along the horizontal direction, and the plurality of speaker units are connected to the waveguide power division unit, and the waveguide power division unit is used to distribute the input electromagnetic wave power to each speaker unit. By arranging a plurality of linear array structures in sequence along the vertical direction to form an array, the structure is simple, and the feeding structure is easy to design; each linear array structure includes a waveguide power division unit and a plurality of speaker units, and the electromagnetic wave power is output to each speaker unit through the waveguide power division unit, and then output by the speaker unit, with a wide frequency band, small side lobes, and higher gain.

[0108] The above are merely embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structural transformations made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A C-band phased array antenna, characterized in that: include: A mounting base and an antenna body, wherein the antenna body is arranged on the mounting base; the antenna body includes a plurality of linear array structures, and the plurality of linear array structures are arranged in sequence along the vertical direction; the linear array structure includes a waveguide power division unit and a plurality of speaker units, and the plurality of speaker units are arranged in sequence along the horizontal direction, and the plurality of speaker units are connected to the waveguide power division unit, and the waveguide power division unit is used to distribute the input electromagnetic wave power to each of the speaker units.

2. The C-band phased array antenna according to claim 1, characterized in that: The speaker unit has a first bell mouth at one end away from the waveguide power splitter unit, the length of the first bell mouth is 40mm-45mm, and the height is 40mm-45mm. The speaker unit has a second bell mouth at one end adjacent to the waveguide power splitter unit, the length of the second bell mouth is 38mm-43mm, and the height is 20mm-25mm. The spacing between the center points of adjacent first bell mouths is 40mm-45mm.

3. The C-band phased array antenna according to claim 1, characterized in that: The waveguide power splitter unit has a waveguide opening at one end away from the speaker unit. The length of the waveguide opening is 38mm-43mm and the height is 20mm-25mm.

4. The C-band phased array antenna according to claim 1, characterized in that: The antenna body has a length of 630mm-640mm, a width of 300mm-310mm, and a height of 360mm-370mm.

5. The C-band phased array antenna according to claim 1, characterized in that: The number of the linear array structures is 8, and each of the linear array structures includes 14 speaker units.

6. The C-band phased array antenna according to claim 1, characterized in that: The linear array structure includes a first linear array mounting plate and a second linear array mounting plate. The first linear array mounting plate and the second linear array mounting plate have the same structure. The first linear array mounting plate and the second linear array mounting plate are mirror-symmetrically arranged in the vertical direction. The first linear array mounting plate and the second linear array mounting plate are detachably connected.

7. The C-band phased array antenna according to claim 6, characterized in that: The first linear array mounting plate and the second linear array mounting plate are both provided with connecting grooves, and the connecting grooves on the first linear array mounting plate and the connecting grooves on the second linear array mounting plate together enclose the waveguide power division unit and the speaker unit.

8. The C-band phased array antenna according to claim 3, characterized in that: The waveguide power splitter unit includes a main waveguide and multiple branch waveguides. The main waveguide is connected to the waveguide port. The main waveguide is also correspondingly connected to multiple branch waveguides. The main waveguide is used to distribute the electromagnetic wave power input from the waveguide port to each branch waveguide. The branch waveguides are correspondingly connected to the speaker unit.

9. The C-band phased array antenna according to claim 8, characterized in that: The main waveguide includes a first branch waveguide, a second branch waveguide, a third branch waveguide, a fourth branch waveguide, a fifth branch waveguide, a sixth branch waveguide and a seventh branch waveguide, the branch waveguide includes a first sub-branch waveguide and a second sub-branch waveguide, the first branch waveguide is connected to the waveguide port, the two ends of the first branch waveguide are respectively connected to two of the second branch waveguides, the two ends of each of the second branch waveguides are connected to the third branch waveguide and the fourth branch waveguide, the third branch waveguide connects the fifth branch waveguide and The sixth branch waveguide, the fourth branch waveguide connects the seventh branch waveguide and one of the first sub-branch waveguides, both ends of the fifth branch waveguide, the sixth branch waveguide and the seventh branch waveguide are respectively connected to one of the second sub-branch waveguides, and the first sub-branch waveguide and the second sub-branch waveguide are each correspondingly connected to one of the speaker units; the waveguide power division unit is symmetrical with respect to the center line of the length direction of the first branch waveguide, and the first sub-branch waveguide is adjacent to the center line of the length direction of the first branch waveguide.

10. The C-band phased array antenna according to claim 1, characterized in that: The antenna body is arranged on the mounting seat at an elevation angle, and the elevation angle is 30°-35°.

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