An antenna subarray and phased array antenna array
By employing functional and structural reuse techniques in phased array antennas, an antenna subarray with four layers of metal waveguide walls was designed, achieving high integration and miniaturization of feeding, calibration coupling, and electromagnetic wave radiation. This solved the problem of integrating the waveguide calibration network with other system components, improving calibration accuracy and system reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- THE 20TH RESEARCH INSTITUTE OF CHINA ELECTRONICS TECHNOLOGY GROUP CORP
- Filing Date
- 2024-01-22
- Publication Date
- 2026-07-14
AI Technical Summary
In existing technologies, waveguide calibration coupling networks are difficult to integrate with other components of the system, resulting in low integration and large size of phased array antenna arrays.
By employing functional reuse and structural reuse techniques, a highly integrated antenna subarray is designed. The integrated design of feeding, calibration coupling, and electromagnetic wave radiation functions is achieved through four layers of metal waveguide walls. The 'I'-shaped cross-section of the coupling waveguide cavity reduces the size of the coupling waveguide and improves calibration accuracy.
It achieves high integration and miniaturization of the phased array antenna system, improves calibration accuracy, avoids the problem of microstrip lines being susceptible to external electromagnetic interference, and has a compact structure and high reliability.
Smart Images
Figure CN117913513B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of antenna technology, and in particular to an antenna subarray and a phased array antenna array. Background Technology
[0002] Phased array radars have developed rapidly in recent years, with antenna array sizes becoming increasingly larger. As system operating time increases, changes in the performance of active components within the array lead to system performance degradation. Therefore, antenna array calibration is necessary to ensure the normal operation of the radar system.
[0003] Array calibration types are divided into internal calibration and external calibration. External calibration is greatly affected by the environment and is usually only suitable for systems with low calibration accuracy requirements. Internal calibration has higher accuracy, but requires an additional internal calibration coupling network within the antenna array.
[0004] In internal calibration methods, there are typically two types of coupling networks: microstrip lines and waveguides. Microstrip line coupling networks are small in size and easy to fabricate and debug; however, their semi-open structure makes them susceptible to external electromagnetic interference, which can reduce calibration accuracy. Waveguide coupling networks are closed networks, less affected by external electromagnetic interference, and offer high calibration accuracy. However, they are large in size and difficult to integrate into systems. Therefore, certain technical means are needed to integrate and design waveguide coupling networks to overcome these drawbacks.
[0005] In the patent "A slotted waveguide, radiating element, waveguide calibration network and phased array antenna", the authors used an additional coupling waveguide structure to couple and calibrate the array. The calibration network and the antenna system are independent components, resulting in low integration of the phased array antenna described in this method.
[0006] With phased array antennas ranging in size from thousands, the importance of phased array antenna calibration is increasingly prominent in order to overcome the system performance degradation caused by factors such as channel faults and electrical performance drift. To ensure calibration accuracy, the main drawback of existing technologies using waveguide-based calibration methods is that they cannot integrate the waveguide calibration coupling network with other system components to a high degree, resulting in low antenna array integration and a large size. Summary of the Invention
[0007] To address, or at least partially address, the problems existing in the prior art, this application proposes a highly integrated antenna subarray and phased array antenna by employing functional reuse and structural reuse techniques.
[0008] This application provides an antenna subarray, including:
[0009] Subarray base A2 is plate-shaped and linear, used to mount the remaining components of the antenna subarray;
[0010] Four linear metal waveguide walls are installed on one side of the subarray base A2. The four metal waveguide walls are arranged in pairs, one pair forming a first feed waveguide and the other forming a second feed waveguide. The two adjacent metal waveguide walls of the first and second feed waveguides are installed back-to-back, forming a coupling waveguide. The first feed waveguide includes a first metal waveguide wall A31 and a second metal waveguide wall A32. The first metal waveguide wall A31, along the direction of the subarray base A2 and at the end furthest from the feed connector A1, has multiple... Each first radiating structure A311 has an arc-shaped side near the second metal waveguide wall A32 and a straight side. The second metal waveguide wall A32 is arranged opposite to the first metal waveguide wall A31 and has the same number of second radiating structures A321. Each second radiating structure A321 has an arc-shaped side near the first metal waveguide wall A31 and a straight side. The first radiating structures A311 and the second radiating structures A321 form an antenna unit to realize the electromagnetic wave radiation function.
[0011] The coupling ports are located at both ends of the coupling waveguide;
[0012] A power supply connector A1 is installed on the other side of the subarray base A2 to power each antenna element separately.
[0013] Optionally, the second feed waveguide includes a third metal waveguide wall A33 and a fourth metal waveguide wall A34;
[0014] The third layer of metal waveguide wall A33 has the same number of third radiation structures A331 as the first radiation structures A311 at the end away from the feed connector A1 along the front-back direction. The third radiation structure A331 is straight on the side near the second layer of metal waveguide wall A32 and arc-shaped on the other side.
[0015] The fourth metal waveguide wall A34 has a number of fourth radiation structures A341, the same as the number of first radiation structures A311, located at the end away from the feed connector A1 along the front-back direction. The fourth radiation structure A341 is straight on the side away from the third metal waveguide wall A33 and arc-shaped on the other side.
[0016] The third radiating structure A331 and the fourth radiating structure A341 form an antenna unit to realize the electromagnetic wave radiation function.
[0017] Optionally, a metal protrusion structure is provided between two adjacent radiating structures in the first layer metal waveguide wall A31 and the fourth layer metal waveguide wall A34, wherein:
[0018] The first metal protrusion structure A312 of the first-layer metal waveguide wall A31 is used to divide the first feed waveguide into multiple sub-waveguides, and the feed joint A1 feeds each antenna unit through each sub-waveguide;
[0019] The second metal protrusion structure A342 of the fourth-layer metal waveguide wall A34 is used to divide the second feed waveguide into multiple sub-waveguides, and the feed joint A1 feeds each antenna unit through each sub-waveguide.
[0020] Optionally, the second-layer metal waveguide wall A32 and the third-layer metal waveguide wall A33 are provided with cross slots having the same number as the second radiation structure A321; and
[0021] The second-layer metal waveguide wall A32 is provided with a first slot line A323 in the front-back direction on the side away from the first-layer metal waveguide wall A31;
[0022] The third-layer metal waveguide wall A33 is provided with a second slot line A333 in the front-back direction on the side close to the second-layer metal waveguide wall A32.
[0023] Optionally, the number of the first radiation structure A311, the second radiation structure A321, the third radiation structure A331, and the fourth radiation structure A341 is 48.
[0024] Optionally, the second-layer metal waveguide wall A32 and the third-layer metal waveguide wall A33 form a coupled waveguide after installation; wherein:
[0025] The coupled waveguide is in the front-back direction;
[0026] The first slot line A323 and the second slot line A333 form the inner cavity of the coupled waveguide;
[0027] The inner cavity cross-section of the coupled waveguide is in an "I" shape, and the cross slots are located on the left and right inner walls of the "I" shape.
[0028] Optionally, any one of the coupling ports includes an SMA RF connector and is arranged at the front and rear ends of the coupled waveguide.
[0029] The embodiment of the present application also proposes a phased array antenna array, including a plurality of antenna sub-arrays arranged in an array as described above.
[0030] The embodiment of the present application conducts a structural reuse and functional reuse design on the four-layer metal waveguide wall, and simultaneously realizes the functions of feeding, calibration coupling, and electromagnetic wave radiation in the same structure, preferably realizes the integrated design of each functional module, and realizes the high integration and miniaturization design of the antenna system.
[0031] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description
[0032] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:
[0033] Figure 1 This is a schematic diagram of an antenna subarray according to an embodiment of this application;
[0034] Figure 2 This is a partial schematic diagram of the first layer of metal waveguide wall of the antenna subarray in an embodiment of this application;
[0035] Figure 3 This is a partial schematic diagram of the second layer of metal waveguide wall of the antenna subarray in an embodiment of this application;
[0036] Figure 4 This is a schematic diagram of the first feed waveguide of the antenna subarray in an embodiment of this application;
[0037] Figure 5 This is a partial schematic diagram of the third layer of metal waveguide wall of the antenna subarray in an embodiment of this application;
[0038] Figure 6 This is a partial schematic diagram of the fourth layer of metal waveguide wall of the antenna subarray in an embodiment of this application;
[0039] Figure 7 This is a schematic diagram of the second feed waveguide of the antenna subarray in an embodiment of this application;
[0040] Figure 8 This is a schematic cross-section of the coupled waveguide of the antenna subarray in an embodiment of this application.
[0041] Figure 9 This is a schematic diagram of the mounting holes for the feed waveguide and coupling waveguide of the antenna subarray in an embodiment of this application;
[0042] Figure 10 This is a schematic diagram of the coupling port structure of the antenna subarray according to an embodiment of this application.
[0043] Figure 11 This is a schematic diagram of the subarray mounting holes of the antenna subarray in an embodiment of this application;
[0044] Figure 12 This is a schematic diagram of the mounting holes on the subarray substrate of the antenna subarray in an embodiment of this application.
[0045] Figure 13 This is a simulation example of the coupling degree of the antenna subarray in an embodiment of this application;
[0046] Figure 14 This is a schematic diagram of the phased array antenna array structure according to an embodiment of this application. Detailed Implementation
[0047] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
[0048] This application provides an antenna subarray, mainly including a feed connector A1, coupling ports (A41, A42, A43, A44), a subarray base A2, and four layers of metal waveguide walls (A31, A32, A33, A34). Metal waveguide walls A31 and A32 form a first feed waveguide, metal waveguide walls A32 and A33 form a coupling waveguide, and metal waveguide walls A33 and A34 form a second feed waveguide. All components of the antenna subarray are mounted and fixed with the subarray base plate A2 as the reference surface. Specifically, as shown... Figure 1 As shown, the antenna subarray in this embodiment includes:
[0049] The subarray base A2 is plate-shaped or linear and is used to mount the remaining components of the antenna subarray. In some examples, the subarray base A2 is provided with corresponding mounting holes, etc.
[0050] Four layers of metal waveguide walls, such as Figure 1 As shown, it is linear and installed on one side of the subarray base A2. The four layers of metal waveguide walls are arranged in pairs, with one pair forming the first feed waveguide and the other forming the second feed waveguide. The two layers of metal waveguide walls of the first feed waveguide and the second feed waveguide are installed opposite each other on the subarray base A2. The two adjacent layers of metal waveguide walls of the first feed waveguide and the second feed waveguide are installed back to back, and the two adjacent layers of metal waveguide walls form a coupling waveguide.
[0051] The first feed waveguide includes a first metal waveguide wall A31 and a second metal waveguide wall A32, as follows: Figure 2 As shown, the first layer of metal waveguide wall A31 has multiple first radiation structures A311 along the direction of subarray base A2 and at the end away from the feed connector A1. Each first radiation structure A311 is arc-shaped on one side near the second layer of metal waveguide wall A32 and straight on the other side.
[0052] like Figure 3 As shown, the second layer of metal waveguide wall A32 is disposed opposite to the first layer of metal waveguide wall A31 and has the same number of second radiating structures A321. Each second radiating structure A321 is arc-shaped on one side near the first layer of metal waveguide wall A31 and straight on the other side. The first radiating structure A311 and the second radiating structure A321 form an antenna element to realize the electromagnetic wave radiation function. In some specific application examples, 48 radiating structures can be set to form 48 antenna elements.
[0053] In some embodiments, the first metal waveguide wall A31 has metal protrusions between adjacent radiating structures. The first metal protrusion A312 of the first metal waveguide wall A31 is used to divide the first feed waveguide into multiple sub-waveguides. The feed connector A1 feeds the antenna element through these sub-waveguides. In some specific examples, such as... Figure 4 As shown, the first metal waveguide wall A31 and the second metal waveguide wall A32, after installation, constitute the first feed waveguide, which runs in the front-to-back direction. Taking 48 radiating structures as an example, the first metal protrusion structure A312 can divide the first feed waveguide into 48 sub-waveguides, which run in the vertical direction. The feed connector A1 feeds the 48 antenna elements through the 48 sub-waveguides respectively.
[0054] The structure of the second feed waveguide is similar to that of the first feed waveguide, and will not be described in detail here.
[0055] The coupling ports are located at both ends of the coupling waveguide.
[0056] A power supply connector A1 is installed on the other side of the subarray base A2 to power each antenna element separately.
[0057] The embodiments of this application employ functional reuse and structural reuse methods to simultaneously realize feeding, calibration coupling and electromagnetic wave radiation functions on the same structure, thereby achieving high integration and miniaturized design of the antenna system.
[0058] In some embodiments, the second feed waveguide includes a third metal waveguide wall A33 and a fourth metal waveguide wall A34;
[0059] like Figure 5 As shown, similar to the second layer metal waveguide wall A32, the third layer metal waveguide wall A33 has the same number of third radiation structures A331 as the first radiation structure A311 at the end away from the feed connector A1 along the front-back direction. The third radiation structure A331 is straight on the side near the second layer metal waveguide wall A32 and arc-shaped on the other side.
[0060] like Figure 6As shown, similar to the first layer of metal waveguide wall A31, the fourth layer of metal waveguide wall A34 has the same number of fourth radiation structures A341 as the first radiation structure A311 at the end away from the feed connector A1 along the front-back direction. The fourth radiation structure A341 is straight on the side away from the third layer of metal waveguide wall A33 and arc-shaped on the other side.
[0061] In some embodiments, the fourth metal waveguide wall A34 has a metal protrusion structure between two adjacent radiating structures, wherein: the second metal protrusion structure A342 of the fourth metal waveguide wall A34 is used to divide the second feed waveguide into multiple sub-waveguides, and the feed connector A1 feeds the antenna element through the sub-waveguides.
[0062] In some specific application examples, the third radiating structure A331 and the fourth radiating structure A341 also form 48 antenna elements, such as... Figure 7 As shown, the third metal waveguide wall A33 and the fourth metal waveguide wall A34 are installed to form the second feeding waveguide. The second metal protrusion structure A342 can divide the second feeding waveguide into 48 sub-waveguides. The feeding connector A1 feeds 48 antenna elements through the 48 sub-waveguides respectively.
[0063] In some embodiments, the second layer of metal waveguide wall A32 and the third layer of metal waveguide wall A33 are provided with the same number of intersecting slots as the second radiating structure A321. Specifically, as shown below... Figure 3 , Figure 5 As shown, the second layer metal waveguide wall A32 and the third layer metal waveguide wall A33 are respectively provided with 48 first intersecting slots A322 and 48 second intersecting slots A332. Among them,
[0064] The second layer of metal waveguide wall A32 has a first groove line A323 in the front-to-back direction on the side away from the first layer of metal waveguide wall A31. In some examples, such as... Figure 3 As shown, two front-to-back first groove lines A323 are provided on the side away from the first layer of metal waveguide wall A31.
[0065] The third metal waveguide wall A33 has a second groove line A333 in the front-to-back direction on the side near the second metal waveguide wall A32. In some examples, such as... Figure 5 As shown, two second groove lines A333 in the front-to-back direction are provided on the side away from the third metal waveguide wall A33.
[0066] In some embodiments, the number of the first radiation structure A311, the second radiation structure A321, the third radiation structure A331, and the fourth radiation structure A341 is 48. In specific implementation, it can be set according to actual needs, and is not limited to the number 48.
[0067] In some embodiments, after the second-layer metal waveguide wall A32 and the third-layer metal waveguide wall A33 are installed, a coupled waveguide is formed; wherein:
[0068] The coupled waveguide is in the front-back direction;
[0069] The first slot line A323 and the second slot line A333 constitute the inner cavity of the coupled waveguide;
[0070] For the coupled waveguide, the cross-section of its inner cavity is in the shape of a 'worker' character, and the cross slots are located on the left and right inner walls of the 'worker' character. In a specific application example, the coupled waveguide is composed of the second-layer metal waveguide wall A32 and the third-layer metal waveguide wall A33, and the coupled waveguide is in the front-back direction. The inner cavity of the coupled waveguide is composed of two slot lines in the front-back direction forming A323 and two slot lines in the front-back direction forming A333. The cross-section of the inner cavity of the coupled waveguide is in the shape of a 'worker' character, as Figure 8 shown. Cross slots A322 and A332 are provided on the left and right inner walls of the 'worker' character. The design of the 'worker'-shaped waveguide inner cavity in the embodiments of the present application is beneficial to reducing the size of the coupled waveguide and realizing a high-integration design with a small volume.
[0071] In some embodiments, any one of the coupling ports includes an SMA radio frequency connector and is provided at the front and rear ends of the coupled waveguide. As Figure 9 shown, it is a schematic diagram of the mounting hole positions of the first feed waveguide, the second feed waveguide, and the coupled waveguide. The installation direction of the A35 hole screw is in the left-right direction.
[0072] Figure 10 Shown is a schematic diagram of the installation of the coupling port structure. A41 is an SMA radio frequency connector, which is installed on the metal structure A42 of the coupling port through the joint flange screw holes. A44 is an SMA radio frequency connector, which is installed on the metal structure A43 of the coupling port through the joint flange screw holes. The metal structure A42 and the metal structure A43 are respectively installed on the first-layer metal waveguide wall A31 and the fourth-layer metal waveguide wall A34 through the screw holes thereon, completing the fixed installation of the coupling port.
[0073] Based on this, the subarray proposed in the present application adopts the methods of functional multiplexing and structural multiplexing to perform an integrated design on the four-layer metal waveguide wall, and simultaneously realizes the functions of feeding, calibration coupling, and electromagnetic wave radiation on the same structure, achieving a high integration and miniaturization design of the antenna system.
[0074] It achieves a high degree of integration in both function and structure.
[0075] In some specific applications Figure 11 The diagram shows the mounting holes for the subarray. Figure 12 This diagram shows the mounting holes on the subarray substrate. Hole A51 is a through hole used to mount the two ends of the subarray onto the antenna array frame. Hole A52 is a through hole, corresponding to hole A24 on subarray substrate A2, and is evenly distributed along the front and back of the subarray to reinforce its mounting on the antenna array frame. Hole A53 corresponds to the flange hole of feed connector A1 and hole A21 on subarray substrate A2, and is used to fix feed connector A1 to subarray base A2. Screw hole A54 is used to fix the four layers of metal waveguide walls to subarray base A2, and corresponds to hole A23 on subarray substrate. Hole A55 is a positioning hole, which cooperates with the positioning structure on the antenna array frame for installation positioning.
[0076] Figure 13 The simulation results of the subarray coupling are shown. As can be seen from the figure, the coupling of the coupled waveguide is around -46dB, and the coupling fluctuation is less than 1.5dB in the 8-12GHz frequency band, with good in-band flatness.
[0077] This application proposes a highly integrated antenna subarray, including a feed connector, a coupling port, a subarray base, and metal waveguide walls. The metal waveguide walls consist of four layers, arranged in pairs to form a three-layer waveguide. The outer two layers of the three-layer waveguide are the first feed waveguide and the second feed waveguide, respectively. The middle layer of the three-layer waveguide is the coupling waveguide. The first feed waveguide consists of 48 sub-waveguides arranged in a front-to-back configuration, each fed from its bottom end by 48 feed connectors. The second feed waveguide also consists of 48 sub-waveguides arranged in a front-to-back configuration, each fed from its bottom end by 48 feed connectors. All feed connectors are SMA RF connectors. The first and second feed waveguides have radiating structures at their ends away from the feed connectors. The coupling waveguide is positioned in a front-to-back direction, orthogonal to the sub-waveguide direction. The cross-section of the coupling waveguide cavity is I-shaped. Cross-slots, respectively connecting the first and second feed waveguides, are etched on the metal walls on both sides of the coupling waveguide for energy coupling from the first and second feed waveguides to the coupling waveguide. The metal walls on both sides of the coupling waveguide are reused by the first and second feed waveguides. The front and rear ends of the coupling waveguide are coupling ports. Each coupling port consists of an RF connector and a metal mounting structure. The feed connector, coupling ports, and metal waveguide walls are all fixedly mounted with the subarray base as the reference plane.
[0078] A waveguide coupling network is used to calibrate the antenna array, overcoming the shortcomings of microstrip calibration networks which are susceptible to external electromagnetic interference, thus improving calibration accuracy. The first and second feed waveguide layers reuse the same coupling waveguide, achieving high functional integration. The middle two layers of the four-layer metal waveguide walls are reused by the feed and coupling waveguides, eliminating the need for additional coupling network structures and achieving high structural integration and a compact design. The antenna subarray can simultaneously perform feeding, coupling, and radiation functions, exhibiting high integration. This subarray is an all-metal structure, with all components manufactured through machining or 3D printing, resulting in a compact, maintenance-free, and highly reliable subarray.
[0079] This application also proposes a phased array antenna array, including multiple antenna subarrays arranged in an array as described above.
[0080] In some application examples, such as Figure 14 As shown, for Figure 1 The subarrays shown are arranged along the left-right direction, resulting in a phased array antenna array as follows: Figure 14 As shown, the phased array antenna array has 24 subarrays in the left and right directions, with a total array size of 48 antenna elements in the left and right directions and 48 antenna elements in the front and back directions.
[0081] All parts of the antenna subarray and phased array antenna array in this application embodiment can be mounted with screws and are all-metal structures, achieving excellent antenna structural strength and stability. The coupling network and antenna front-end employ functional and structural reuse techniques, achieving high system integration and miniaturization. The antenna subarray and phased array antenna coupling network in this application embodiment adopt waveguide form, avoiding the problem of microstrip line form being easily affected by external electromagnetic interference and improving calibration accuracy. The coupling waveguide adopts an "I"-shaped waveguide, achieving miniaturization and compact design. The phased array antenna array of this application has a simple array arrangement, compact and stable antenna structure, and high integration.
[0082] It should be noted that, in the embodiments of this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.
[0083] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.
[0084] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims. All of these forms are within the protection scope of this application.
Claims
1. An antenna subarray, characterized in that, include: The subarray base (A2) is plate-shaped and linear, used to mount the remaining components of the antenna subarray; Four layers of metal waveguide walls, in a linear shape, are installed on one side of the subarray base (A2). The four layers of metal waveguide walls are arranged in pairs, with one pair forming the first feed waveguide and the other forming the second feed waveguide. The two adjacent metal waveguide walls of the first feed waveguide and the second feed waveguide are installed back to back, and the two adjacent metal waveguide walls form a coupling waveguide. The coupling ports are located at the front and rear ends of the coupling waveguide. A power supply connector (A1) is installed on the other side of the subarray base (A2) to power each antenna element separately; The first feed waveguide includes a first metal waveguide wall (A31) and a second metal waveguide wall (A32); The first layer of metal waveguide wall (A31) has multiple first radiating structures (A311) along the direction of the subarray base (A2) and away from the feed connector (A1). Each first radiating structure (A311) is arc-shaped on the side near the second layer of metal waveguide wall (A32) and straight on the other side. The second layer of metal waveguide wall (A32) is arranged opposite to the first layer of metal waveguide wall (A31) and has the same number of second radiating structures (A321) as the first radiating structures (A311). Each second radiating structure (A321) is arc-shaped on the side near the first layer of metal waveguide wall (A31) and straight on the other side. The first radiating structures (A311) and the second radiating structures (A321) form an antenna unit to realize the electromagnetic wave radiation function. The second feed waveguide includes a third metal waveguide wall (A33) and a fourth metal waveguide wall (A34); The third layer of metal waveguide wall (A33) has the same number of third radiation structures (A331) as the first radiation structure (A311) at the end away from the feed connector (A1) along the front-back direction. The third radiation structure (A331) is straight on the side near the second layer of metal waveguide wall (A32) and arc-shaped on the other side. The fourth metal waveguide wall (A34) has a fourth radiating structure (A341) in the same number as the first radiating structure (A311) at the end away from the feed connector (A1) along the front-back direction. The fourth radiating structure (A341) is straight on the side away from the third metal waveguide wall (A33) and arc-shaped on the other side. The third radiating structure (A331) and the fourth radiating structure (A341) form an antenna unit to realize the electromagnetic wave radiation function.
2. The antenna subarray as described in claim 1, characterized in that, The first layer of metal waveguide wall (A31) and the fourth layer of metal waveguide wall (A34) have metal protrusion structures between adjacent radiating structures, wherein: The first metal protrusion structure (A312) of the first layer of metal waveguide wall (A31) is used to divide the first feed waveguide into multiple sub-waveguides, and the feed connector (A1) feeds each antenna element through each sub-waveguide; The second metal protrusion structure (A342) of the fourth-layer metal waveguide wall (A34) is used to divide the second feed waveguide into multiple sub-waveguides, and the feed joint (A1) feeds each antenna unit through each sub-waveguide respectively.
3. The antenna subarray as described in claim 1, characterized in that, The second-layer metal waveguide wall (A32) and the third-layer metal waveguide wall (A33) are provided with cross slots having the same number as the second radiation structure (A321); and The second-layer metal waveguide wall (A32) is provided with a first slot line (A323) in the front-back direction on the side far from the first-layer metal waveguide wall (A31); The third-layer metal waveguide wall (A33) is provided with a second slot line (A333) in the front-back direction on the side close to the second-layer metal waveguide wall (A32).
4. The antenna subarray as described in claim 1, characterized in that, The number of the first radiation structure (A311), the second radiation structure (A321), the third radiation structure (A331), and the fourth radiation structure (A341) is 48.
5. The antenna subarray as described in claim 3, characterized in that, The second-layer metal waveguide wall (A32) and the third-layer metal waveguide wall (A33) form a coupled waveguide after installation; wherein: The coupled waveguide is in the front-back direction; The first slot line (A323) and the second slot line (A333) constitute the inner cavity of the coupled waveguide; For the coupled waveguide, the cross section of its inner cavity is in an "I" shape, and the cross slots are located on the left and right inner walls of the "I" shape.
6. The antenna subarray as described in claim 1, characterized in that, Any one of the coupled ports includes an SMA RF connector and is arranged at the front and rear ends of the coupled waveguide.
7. A phased array antenna array, characterized in that, It includes a plurality of antenna sub-arrays arranged in an array as described in any one of claims 1-6.