Directional Couplers and Antennas

Abstract

This application relates to a directional coupler and an antenna. The directional coupler includes: a dielectric substrate; and a first signal line and a second signal line disposed on the dielectric substrate and insulated from each other. One of the first and second signal lines has its two ends forming an input port and a through port, respectively, while the other has its two ends forming a coupling port and an isolation port, respectively. The first signal line includes a first connecting line and a first loop structure connected together, and the second signal line includes a second connecting line and a second loop structure connected together. A portion of the first connecting line is located inside the second loop structure, forming a bilateral coupling circuit with that portion. A portion of the second connecting line is located inside the first loop structure, forming a bilateral coupling circuit with that portion. The directional coupler and antenna of this application are small in size, enabling miniaturization and weight reduction.

Description

Technical Field

[0001] This invention relates to the field of radio frequency technology, and in particular to a directional coupler and antenna. Background Technology

[0002] With the continuous development of communication technology, people have put forward more requirements for antenna products, such as multi-frequency and multi-port, and miniaturization. To achieve multi-frequency and multi-port while also miniaturizing, the spacing between the arrays of antenna radiating elements will be reduced accordingly. This will lead to significant mutual coupling between antenna columns, and will also deteriorate key indicators such as horizontal beamwidth, front-to-back ratio, and gain. The application of directional couplers in antennas is an effective way to solve the above problems. Specifically, in side-by-side array antennas, a directional coupler is connected to the feed network between the two arrays, allowing one or more radiating elements in adjacent columns to be multiplexed, achieving the effect of horizontal beam superposition, thereby improving the directionality of antenna radiation. The directional coupler of related technologies usually includes a first coupling line and a second coupling line, which are spaced apart and arranged adjacently. The first and second coupling lines have parallel coupling segments. The two ports of the first coupling line are used as the input port and the through port, respectively, and the two ports of the second coupling line are used as the coupling port and the isolation port, respectively. In practical applications, the electrical length of the coupling segment is generally set to be relatively long, thereby achieving the effect of reducing and converging the horizontal beamwidth. However, this results in a larger module size for the directional coupler, which is also not conducive to further miniaturization and weight reduction of the antenna. Summary of the Invention

[0003] Therefore, it is necessary to provide a directional coupler and antenna that is smaller in size and can be miniaturized and lightweight.

[0004] In a first aspect, this application provides a directional coupler, comprising:

[0005] dielectric substrate; and

[0006] The first signal line and the second signal line are disposed on the dielectric substrate and are insulated from each other. In the first signal line and the second signal line, the ports at both ends of one of them are respectively formed as an input port and a through port, and the ports at both ends of the other are respectively formed as a coupling port and an isolation port.

[0007] The first signal line includes a first connecting line and a first ring structure connected together; the second signal line includes a second connecting line and a second ring structure connected together; the second ring structure has a portion of the first connecting line on its inner side, and forms a bilateral coupling circuit with the portion of the first connecting line; the first ring structure has a portion of the second connecting line on its inner side, and forms a bilateral coupling circuit with the portion of the second connecting line.

[0008] In some embodiments, the number of both the first ring structure and the second ring structure is at least one;

[0009] The first connecting line includes a first connecting segment, a first coupling segment, and a first bridging circuit. The first connecting segment is located outside the second ring structure, and the first coupling segments are correspondingly located inside the second ring structure. One of the first coupling segments is bridged with the first connecting segment through the first bridging circuit.

[0010] The second connecting line includes a second connecting segment, a second coupling segment, and a second bridging circuit. The second connecting segment is located outside the first ring structure, and the second coupling segments are correspondingly located inside the first ring structure. One of the second coupling segments is bridged with the second connecting segment through the second bridging circuit.

[0011] In some embodiments, the number of both the first ring structure and the second ring structure is multiple;

[0012] Each first coupling segment is bridged by a first bridging circuit, and each second coupling segment is bridged by a second bridging circuit.

[0013] In some embodiments, the first bridging circuit includes a first bridging metal and two spaced-apart first metallized vias, the two first metallized vias penetrating the dielectric substrate, the first bridging metal being disposed on the side of the dielectric substrate opposite to the first signal line, and electrically connecting the two first metallized vias.

[0014] The second bridging circuit includes a second bridging metal and two spaced-apart second metallized vias. The two second metallized vias penetrate the dielectric substrate. The second bridging metal is located on the side of the dielectric substrate opposite to the second signal line and electrically connects the two second metallized vias.

[0015] In some embodiments, the first ring structure includes two first sub-segments that are arranged opposite to each other and parallel to each other, and the second ring structure includes two second sub-segments that are arranged opposite to each other and parallel to each other.

[0016] The second coupling segment is spaced apart from and parallel to the two first sub-segments of the corresponding first ring structure to form a bilateral coupling circuit with the first ring structure. The first coupling segment is spaced apart from and parallel to the two second sub-segments of the corresponding second ring structure to form a bilateral coupling circuit with the second ring structure.

[0017] In some embodiments, the width of the first sub-segment is less than the width of the first connecting segment, and the width of the second sub-segment is less than the width of the second connecting segment.

[0018] In some embodiments, of the two first connecting segments connected by the first coupling segment, one of the first connecting segments is connected to the first ring structure, and the other first connecting segment forms a port of the first signal line at one end away from the first coupling segment.

[0019] Of the two second connecting segments connected by the second coupling segment, one of the second connecting segments is connected to the second ring structure, and the other second connecting segment forms a port of the second signal line at one end away from the second coupling segment.

[0020] In some embodiments, the first annular structure and the second annular structure are arranged staggered along the first direction and the second direction, respectively.

[0021] Both the first sub-segment and the second sub-segment extend along the first direction;

[0022] The first direction and the second direction are perpendicular to each other and both parallel to the dielectric substrate.

[0023] In some embodiments, when there are multiple first ring structures, the multiple first ring structures are arranged in a row at intervals along the second direction and are electrically connected to each other; when there are multiple second ring structures, the multiple second ring structures are arranged in a row at intervals along the second direction and are electrically connected to each other.

[0024] In some embodiments, when the number of the first ring structure and the second ring structure is one, the length of the first segment and the length of the second segment are both in the range of λ / 16-λ / 8.

[0025] When there are two first ring structures and two second ring structures, the length of the first sub-segment and the length of the second sub-segment are both in the range of λ / 32-λ / 16.

[0026] Where λ is the operating center frequency of the electromagnetic wave.

[0027] Secondly, this application provides an antenna including the aforementioned directional coupler.

[0028] In some embodiments, it further includes a phase shifter, a first column of oscillators, and a second column of oscillators;

[0029] The feed terminal of one of the oscillators in the first column is connected to the input port of the directional coupler; the feed terminal of one of the oscillators in the second column is connected to the isolation port of the directional coupler.

[0030] In the aforementioned directional coupler and antenna, the first signal line includes a first loop structure, and the second signal line includes a second loop structure. The inner side of the second loop structure has a portion containing a first connecting line, forming a bilateral coupling circuit with this first connecting line portion. The inner side of the first loop structure has a portion containing a second connecting line, also forming a bilateral coupling circuit with this second connecting line portion. Thus, the bilateral coupling circuit formed by the first loop structure creates a bilateral coupling path, whose path length is twice that of a typical parallel coupling path. Therefore, to achieve the same target coupling path length, the first loop structure with a bilateral coupling circuit can reduce the physical length by at least half. The second loop structure operates on a similar principle. Therefore, by incorporating bilateral coupling circuits in both the first and second loop structures, a smaller physical length can achieve the target coupling length of existing parallel couplers, resulting in a smaller size and weight for the directional coupler, and enabling miniaturization and weight reduction of the antenna. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the structure of a directional coupler according to some embodiments of this application.

[0033] Figure 2 This is a top view of the first and second signal lines in a directional coupler according to some embodiments of this application.

[0034] Figure 3 This is an exploded view of the first and second signal lines in a directional coupler according to some embodiments of this application.

[0035] Figure 4 This is a schematic diagram of the structure of the first signal line and the second signal line in some other embodiments of this application.

[0036] Figure 5 This is a schematic diagram of the structure of the first signal line and the second signal line in some embodiments of this application.

[0037] Figure 6 This is a schematic diagram of the antenna structure of some embodiments of this application.

[0038] Figure 7 The VSWR curves are for some embodiments of the directional coupler in this application.

[0039] Figure 8The following are characteristic curves of directional couplers in some embodiments of this application.

[0040] Figure 9 This is the gain curve of the antenna.

[0041] Icon labels:

[0042] 100. Directional coupler;

[0043] 11. Input port; 12. Straight-through port; 13. Coupling port; 14. Isolation port;

[0044] 2. Dielectric substrate;

[0045] 3. First signal line; 31. First connecting line; 311. First connecting segment; 312. First coupling segment; 32. First ring structure; 321. First sub-segment;

[0046] 41. First bridging circuit; 411. First bridging metal; 412. First metallized via; 42. Second bridging circuit; 421. Second bridging metal; 422. Second metallized via;

[0047] 5. Second signal line; 51. Second connecting line; 511. Second connecting segment; 512. Second coupling segment; 52. Second ring structure; 521. Second sub-segment;

[0048] 6. Grounding layer;

[0049] 200. Antenna; 201. Phase shifter; 202. Vibrator; 203. First conductor; 204. Second conductor;

[0050] F, first direction; S, second direction. Detailed Implementation

[0051] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0052] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0054] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0055] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0056] It should be noted that an element is referred to as being "fixed to" or "set on" another element, which may be directly on the other element or may also include an intervening element. An element is considered to be "connected" to another element, which may be directly connected to the other element or may also include an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0057] See Figures 1 to 5 , Figure 1 This is a schematic diagram of the structure of a directional coupler according to some embodiments of this application. Figure 2 This is a top view of the first and second signal lines in a directional coupler according to some embodiments of this application. Figure 3 This is an exploded view of the first and second signal lines in a directional coupler according to some embodiments of this application. Figure 4 This is a schematic diagram of the structure of the first signal line and the second signal line in some other embodiments of this application. Figure 5 This is a schematic diagram of the structure of the first signal line and the second signal line in some embodiments of this application.

[0058] The directional coupler 100 provided in this application embodiment includes a dielectric substrate 2, a first signal line 3, and a second signal line 5.

[0059] The first signal line 3 and the second signal line 5 are disposed on the dielectric substrate 2 and are insulated from each other. The ports at both ends of the first signal line 3 and the second signal line 5 are respectively formed as an input port 11 and a through port 12, and the ports at both ends of the other are respectively formed as a coupling port 13 and an isolation port 14.

[0060] In the first signal line 3 and the second signal line 5, the ports at both ends of one are respectively formed as an input port 11 and a through port 12, and the ports at both ends of the other are respectively formed as a coupling port 13 and an isolation port 14. For example, it can be as follows: Figure 2 As shown, the ports at both ends of the first signal line 3 form an input port 11 and a through port 12, respectively, and the ports at both ends of the second signal line 5 form a coupling port 13 and an isolation port 14, respectively. Alternatively, it can be done as follows: Figure 4 As shown, the ports at both ends of the second signal line 5 form an input port 11 and a through port 12, respectively, while the ports at both ends of the first signal line 3 form a coupling port 13 and an isolation port 14, respectively. Furthermore, both the first signal line 3 and the second signal line 5 can be configured as microstrip lines. And the first signal line 3 and the second signal line 5 can be arranged symmetrically (the symmetrical point is as follows...). Figure 2 Midpoint O), thus, can be achieved as follows Figure 2 , Figure 4This is a 2-in, 2-out port reciprocal microwave device as shown. Furthermore, the first signal line 3 and the second signal line 5 can be arranged symmetrically at the center, which can effectively improve the port isolation effect.

[0061] Furthermore, by adding bilateral coupling, its equivalent coupling length is the same as in related technologies. Therefore, it is possible to reduce the physical length while achieving the same functionality as existing technologies.

[0062] The first signal line 3 includes a first connecting line 31 and a first ring structure 32 connected together. The second signal line 5 includes a second connecting line 51 and a second ring structure 52 connected together. A portion of the first connecting line 31 is located inside the second ring structure 52, forming a bilateral coupling circuit with that portion. A portion of the second connecting line 51 is located inside the first ring structure 32, forming a bilateral coupling circuit with that portion.

[0063] The first signal line 3 includes a first ring structure 32, and the second signal line 5 includes a second ring structure 52. The second ring structure 52 has a portion of a first connecting line 31 on its inner side, forming a bilateral coupling circuit with this portion of the first connecting line 31. The first ring structure 32 also has a portion of a second connecting line 51 on its inner side, forming a bilateral coupling circuit with this portion of the second connecting line 51. Thus, the bilateral coupling circuit formed by the first ring structure 32 creates a bilateral coupling path, whose path length is twice that of a typical parallel coupling path. Therefore, to achieve the same target coupling path length, the first ring structure 32 with the bilateral coupling circuit can reduce the physical length by at least half. The second ring structure 52 operates on a similar principle. Therefore, by providing bilateral coupling circuits in both the first and second ring structures 32, a smaller physical length can achieve the target coupling length of existing parallel couplers, resulting in a smaller size and weight for the directional coupler 100, and enabling miniaturization and weight reduction of the antenna 200.

[0064] The second ring structure 52 has a portion of the first connecting line 31 inside, forming a bilateral coupling circuit with the portion of the first connecting line 31. This means that regardless of the number of second ring structures 52, each second ring structure 52 has a portion of the first connecting line 31 inside, and each second ring structure 52 forms a bilateral coupling circuit with the corresponding portion of the first connecting line 31. The first ring structure 32 has a portion of the second connecting line 51 inside, forming a bilateral coupling circuit with the portion of the second connecting line 51. This means that regardless of the number of first ring structures 51, each first ring structure 51 has a portion of the second connecting line 52 inside, and each first ring structure 51 forms a bilateral coupling circuit with the corresponding portion of the second connecting line 31.

[0065] exist Figure 2 In the description using the first ring structure 32 as an example, the upper edge of the first ring structure 32 and a portion of the second connecting line 51 inside the first ring structure 32 are close to each other (for example, the spacing d1 < 1 mm) to form electrical signal coupling. The lower edge of the first ring structure 51 is close to a portion of the second connecting line 51 inside the first ring structure 32 (for example, the spacing d2 < 1 mm) to form another segment of electrical signal coupling, thus forming a double-sided coupling circuit. It is understood that the spacings d1 and d2 can be adjusted according to actual needs, thereby flexibly adjusting the coupling strength of the directional coupler 100.

[0066] Similarly, for the second ring structure 52, the upper edge of the second ring structure 52 is close to a portion of the first connecting line 31 inside the second ring structure 52, forming electrical signal coupling. The lower edge of the second ring structure 52 is close to a portion of the first connecting line 31 inside the second ring structure 52, forming another segment of electrical signal coupling. Thus, a double-coupled circuit is formed.

[0067] Of course, the bilateral coupling circuits in the first ring structure 32 and the second ring structure 52 can be bilateral parallel coupling circuits. That is, the two coupling paths formed in the bilateral coupling circuit are parallel to each other.

[0068] In some embodiments, the number of both the first annular structure 32 and the second annular structure 52 is at least one. For example, it can be as follows: Figure 2 As shown, the number of the first ring structure 32 and the second ring structure 52 is one, or it can be as follows: Figure 5 As shown, there are two of each of the first ring structure 32 and the second ring structure 52. The two first ring structures 32 are electrically connected to each other, and the two second ring structures 52 are electrically connected to each other. It is understood that the number of the first ring structure 32 and the second ring structure 52 can also be other than the number of the second ring structure 52, as long as the number of the first ring structure 32 and the second ring structure 52 is equal.

[0069] Reference Figure 3 The first connecting line 31 includes a first connecting segment 311, a first coupling segment 312, and a first bridging circuit 41. The first connecting segment 311 is located outside the second ring structure 52, and the first coupling segments 312 are correspondingly located inside the second ring structure 52. One of the first coupling segments 312 is bridged with the first connecting segment 311 through the first bridging circuit 41.

[0070] The second connecting line 51 includes a second connecting segment 511, a second coupling segment 512, and a second bridging circuit 42. The second connecting segment 511 is located outside the first ring structure 32, and the second coupling segments 512 are correspondingly located inside the first ring structure 32. One of the second coupling segments 512 is bridged with the second connecting segment 511 through the second bridging circuit 42.

[0071] With this configuration, a portion of the first signal line 3 can be bridged into the second ring structure 52, and a portion of the second signal line 5 can be bridged into the first ring structure 32. Even if the first connecting segment 311, the first coupling segment 312, the second connecting segment 511, and the second coupling segment 512 are coplanar, they can still be mutually insulated.

[0072] In this embodiment of the application, when there are multiple first ring structures 32 and multiple second ring structures 52, Figure 5 In the example where there are two of each of the first ring structure 32 and the second ring structure 52, each of the first coupling segments 312 is also bridged by the first bridging circuit 41, and each of the second coupling segments 512 is also bridged by the second bridging circuit 42. Of course, when the number of the first ring structure 32 and the second ring structure 52 is other than that, each of the first coupling segments 312 is still bridged by the first bridging circuit 41, and each of the second coupling segments 512 is still bridged by the second bridging circuit 42.

[0073] In the specific implementation, you can refer to Figure 1 The first bridging circuit 41 includes a first bridging metal 411 and two spaced-apart first metallized holes 412. The two first metallized holes 412 penetrate the dielectric substrate 2. The first bridging metal 411 is disposed on the side of the dielectric substrate 2 away from the first signal line 3 and electrically connects the two first metallized holes 412.

[0074] The second bridging circuit 42 includes a second bridging metal 421 and two spaced-apart second metallized holes 422. The two second metallized holes 422 penetrate the dielectric substrate 2. The second bridging metal 421 is disposed on the side of the dielectric substrate 2 away from the second signal line 5 and electrically connects the two second metallized holes 422.

[0075] When explaining using the bridging of the first coupling segment 312 inside the second annular structure 52 and the first connecting segment 311 outside the second annular structure 52 as an example, for example... Figure 1The rightmost part of the middle image shows the first coupling segment 312 and the first connecting segment 311. The end of the first coupling segment 312 contacts one of the first metallized vias 412, and the end of the first connecting segment 311 contacts the other first metallized via 412. These two first metallized vias 412 are electrically connected through a first bridging metal 411, thus achieving electrical connection between the ends of the first coupling segment 312 and the first connecting segment 311. This is equivalent to sinking the electrical connection path of the first coupling segment 312 and the second connecting segment 311 onto the dielectric substrate 2, thereby achieving coplanarity between the first coupling segment 312 and the first connecting segment 311. The bridging between the second coupling segment 512 and the second connecting segment 511, the bridging between adjacent second coupling segments 512, and the bridging between adjacent first coupling segments 312 are similar and will not be described further here.

[0076] Specifically, a ground layer 6 is provided on the side of the dielectric substrate 2 away from the first signal line 3 and the second signal line 5. The ground layer 6 is disposed in the same layer as the first bridging metal 411 and the second bridging metal 421 and is spaced apart from each other. For example, the ground layer 6 can surround and be spaced around the first bridging metal 411 and the second bridging metal 421.

[0077] In some embodiments, continue to refer to Figure 3 The first ring structure 32 includes two oppositely arranged and parallel first sub-segments 321, and the second ring structure 52 includes two oppositely arranged and parallel second sub-segments 521. A second coupling segment 512 is spaced apart from and parallel to the two first sub-segments 321 of the corresponding first ring structure 32 to form a bilateral parallel coupling circuit with the first ring structure 32. Similarly, a first coupling segment 312 is spaced apart from and parallel to the two second sub-segments 521 of the corresponding second ring structure 52 to form a bilateral parallel coupling circuit with the second ring structure 52.

[0078] Furthermore, the width of the first sub-segment 321 is smaller than the width of the first connecting segment 311, and the width of the second sub-segment 521 is smaller than the width of the second connecting segment 511. This results in a change from a loop structure to a non-loop structure in the first signal line 3 and the second signal line 5, which leads to a change in impedance, i.e., achieving impedance matching and solving the impedance mismatch problem caused by distributed reactance in related technologies.

[0079] Generally speaking, the linewidth of the coupling segment of the two signal lines in a parallel-line coupler of related technologies remains constant (typically 50Ω). In this embodiment, the width of the first sub-segment 321 is smaller than the width of the first connecting segment 311, making the impedance of the first ring structure 32 greater than that of the first connecting segment 311 (e.g., greater than 50Ω). This configuration makes the first ring structure 32 form a ring structure with higher impedance. Since the first ring structure 32 and the first connecting segment 311 are continuously arranged, the difference in impedance creates an impedance transformation, which can help to broaden the operating bandwidth of the directional coupler 100. In specific implementation, if the impedance R1 of the first connecting segment 311 is 50Ω, the impedance R2 of the first sub-segment 321 can be 100Ω. Here, it is sufficient that R1 and R2 satisfy the following relationship:

[0080] R1 / 2*50=R2*R2.

[0081] The case where the width of the second sub-segment 521 is smaller than the width of the second connecting segment 511 is similar to the above and will not be repeated here. Similarly, if the impedance R3 of the second connecting segment 511 is 50Ω, the impedance R4 of the second sub-segment 521 can be 100Ω. Here, it is sufficient that R3 and R4 satisfy the following relationship:

[0082] R3 / 2*50=R4*R4.

[0083] In other words, in the first signal line 3 and the second signal line 5, the change from a ring structure to a non-ring structure is achieved, realizing impedance change and matching. This solves the problem that the coupling section of the traditional parallel-line directional coupler has distributed reactance, requiring impedance matching design in the non-coupling section, which is not conducive to achieving wideband operation.

[0084] In this embodiment, reference is continued. Figure 3 Of the two first connecting segments 311 connected by the first coupling segment 312, one of the first connecting segments 311 is connected to the first ring structure 32, and the other first connecting segment 311 forms a port of the first signal line 3 at one end away from the first coupling segment 312. Of course, one end of the other first connecting segment 311 is connected to the first ring structure 32, and the other end forms another port of the first signal line 3 (e.g., input port 11).

[0085] Of the two second connection segments 511 connected by the second coupling segment 512, one of the second connection segments 511 is connected to the second ring structure 52, and the other second connection segment 511 forms a port of the second signal line 5 at one end away from the second coupling segment 512. Of course, one end of the other second connection segment 511 is connected to the second ring structure 52, and the other end forms another port of the second signal line 4 (e.g., isolation port 14).

[0086] Furthermore, the first annular structure 32 and the second annular structure 52 are staggered along the first direction F and the second direction S. The first sub-segment 321 and the second sub-segment 521 both extend along the first direction F. The first direction F and the second direction S are perpendicular to each other and both parallel to the dielectric substrate 2. Specifically, as shown in the implementation... Figure 3 As shown, the first coupling segment 312 and the second coupling segment 512 can extend along the first direction F. The first connecting segment 311 connected to one side of the first annular structure 32 extends along the first direction F. The first connecting segment connected to the other side of the first annular structure 32 is connected to one end of the first coupling segment 312 and extends along the second direction S. Another first connecting segment 311 connected to the first coupling segment 312 extends partly along the first direction F and partly along the second direction S, forming a right angle. In the part extending along the first direction F, the free end forms a straight-through port 12. Correspondingly, the second connecting segment 511 connected to one side of the second annular structure 52 extends along the first direction F. The second connecting segment 511 connected to the other side of the second annular structure 52 is connected to one end of the second coupling segment 512 and extends along the second direction S. Another second connecting segment 511 connected to the second coupling segment 512 extends partly along the first direction F and partly along the second direction S, forming a right angle. In the part extending along the first direction F, the free end forms a coupling port 13.

[0087] Continue to refer to Figure 5 In some other embodiments, when there are multiple first ring structures 32, the multiple first ring structures 32 are arranged in a row at intervals along the second direction S and are electrically connected to each other. This electrical connection can be achieved by a first bridging circuit. When there are multiple second ring structures 52, the multiple second ring structures 52 are arranged in a row at intervals along the second direction S and are electrically connected to each other. This electrical connection can be achieved by a second bridging circuit.

[0088] In this embodiment of the application, when the number of the first ring structure 32 and the second ring structure 52 is one, the length of the first sub-segment 321 and the length L1 of the second sub-segment 521 are both in the range of λ / 16-λ / 8.

[0089] Within this length range, the longer the length of the first segment 321 and the second segment 521, the more the in-band flatness of the coupling port can be reduced. This principle is applied to wideband side-by-side antennas, which helps to improve the convergence of the antenna's horizontal beamwidth.

[0090] When the first ring structure 32 and the second ring structure 52 are formed, taking the example that the length of the first segment 321 and the second bullet 521 are both λ / 16, since it is a bilateral coupling, the coupling path of the first ring structure 32 and the second ring structure 52 is λ / 8. Together, the total coupling path is λ / 4, which is equivalent to a parallel coupler with a coupling length of λ / 4. However, the total physical length of the first ring structure 32 and the second ring structure 52 is only λ / 8.

[0091] Reference Figure 5 When there are two of each of the first ring structure 32 and the second ring structure 52, the length L2 of the first segment 321 and the second segment 521 is both λ / 32-λ / 16, where λ is the operating center frequency of the electromagnetic wave. Similarly, taking the physical length of one ring structure as an example, because it is bilateral coupling, the coupling path of one ring structure reaches λ / 16. Because there are four ring structures, the total coupling path is λ / 4, but the total physical length of the first ring structure 32 and the second ring structure 52 is only λ / 16.

[0092] Figure 6 This is a schematic diagram of the antenna structure of some embodiments of this application.

[0093] Reference Figure 6 The second aspect of this application also provides an antenna 200, including the aforementioned directional coupler 100. The antenna 200 in this application is a side-by-side array antenna, where the feed network between two element arrays can be connected to the directional coupler 100, allowing one element in an adjacent column to be multiplexed, achieving horizontal beam superposition and improving the directivity of the antenna 200's radiation. That is, due to the connection of the directional coupler 100 to the antenna feed network, the gain of the antenna 200 increases, the horizontal beamwidth decreases (converges), and the front-to-back ratio improves.

[0094] Specifically, the antenna 200 also includes a phase shifter 201, a first column of elements, and a second column of elements. One of the elements 202 in the first column of elements, for example... Figure 6 The feed terminal of the rightmost oscillator 202 in the first column is connected to the input port 11 of the directional coupler 100, so that the feed terminal of the rightmost oscillator 202 in the first column is connected to the through port 12 of the directional coupler. One of the oscillators in the second column, for example... Figure 6 The power supply terminal of the rightmost oscillator 202 in the second column is connected to the isolation port 14 of the directional coupler 100, so that the power supply terminal of the rightmost oscillator 202 in the second column is connected to the coupling port 13 of the directional coupler 100.

[0095] In the specific implementation, you can refer to Figure 6As shown, taking the example where there are three oscillators 202 in both the first and second columns, the phase shifter 201 can be a one-to-three phase shifter. For phase shifter 201-A, the total signal enters from the In port of phase shifter 201 and is then split into three paths. Two of these paths enter the feed terminals of the two oscillators 202 in the upper column from the -1φ and 0φ ports respectively through the first wire 203. The remaining path enters from the +1φ port and is connected to the through port 12 of the directional coupler 100 through the second wire 204. For phase shifter 201-B, the total signal enters from the In port of phase shifter 201 and is then split into three paths. Two of these paths enter the feed terminals of the two oscillators 202 in the lower column from the -1φ and 0φ ports respectively through the first wire 203. The remaining path enters from the +1φ port and is connected to the coupling port 13 of the directional coupler 100 through the second wire 204.

[0096] It is worth noting that since the directional coupler 100 is also a transmission line, it can be equivalently regarded as a conductor of length L. Because the directional coupler 100 is inserted between the +1φ port of the phase shifter and the rightmost oscillator 202, the first conductor 203 between the other ports of the phase shifter 201 and the corresponding oscillator 202 must be supplemented with a conductor of length L. This ensures that the signal at the IN port is synchronized across all oscillators.

[0097] Because the physical length of the signal line in the directional coupler 100 in this embodiment can be shortened, the extended portion L of each first conductor 204 can be shortened accordingly, thereby reducing the volume of the antenna 200.

[0098] Figure 7 The VSWR curves are shown for some embodiments of the directional coupler in this application. Figure 7 In the diagram, the horizontal axis represents the electromagnetic wave frequency (MHz) when the directional coupler is operating, and the vertical axis represents the standing wave ratio (SWR). Figure 7 It reflects the reflection characteristics within the operating bandwidth of the directional coupler, or the degree of matching between the directional coupler and the characteristic impedance of the communication system (theoretically, the closer to 1, the better). Figure 7 The four curves in the figure reflect the VSWR (Standing Wave Ratio) curves of the four ports: input port 11, through port 12, coupling port 13, and isolation port 14. As can be seen from the figure, the VSWR curves for all four ports are less than 1.1, indicating that the directional coupler of this embodiment can achieve good impedance matching within the operating frequency range. Specifically, within the operating frequency band of 700-960MHz, the VSWR of the four curves is <1.1, demonstrating good operating performance over a large bandwidth.

[0099] Figure 8 These are characteristic curves of directional couplers according to some embodiments of this application. Figure 8In the graph, the horizontal axis represents the operating frequency range (MHz), and the vertical axis represents the power level. This curve illustrates the electromagnetic transmission characteristics from input port 11 to the other three ports: through port 12, coupling port 13, and isolation port 14.

[0100] exist Figure 8 In the diagram, the solid line at the top represents the electromagnetic transmission characteristics from input port 11 to through port 12. The dashed line in the middle represents the electromagnetic transmission characteristics from input port 11 to coupling port 13. The double-dotted line at the bottom represents the transmission characteristics from input port 11 to isolation port 14.

[0101] In the middle curve representing the electromagnetic transmission characteristics from input port 11 to coupling port 13, the curve is not a straight line, but rather slopes downwards from left to right, indicating that the directional coupler of this application can reduce the in-band flatness of coupling port 13. In the bottom curve representing the transmission characteristics from input port 11 to isolation port 14, the entire curve is less than -29dB, demonstrating the excellent isolation characteristics of the electromagnetic signals from input port 11 to isolation port 14. Specifically, within the operating frequency range of 700-960MHz, the port isolation is >29dB, achieving the directionality of the directional coupler.

[0102] Figure 9 This is the antenna gain curve. Figure 9 In the diagram, the horizontal axis represents the spatial azimuth angle (°), and the vertical axis represents the gain (dB). The solid line represents the gain curve of the antenna after using the directional coupler of the embodiment of this application, and the dashed line represents the gain curve without using the directional coupler. From Figure 9 As can be seen, the antenna 200 with the directional coupler 100 (maximum gain 12.58dB) has higher gain and better directivity than the unused antenna (maximum gain 12.13dB).

[0103] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0104] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A directional coupler characterized by, The application relates to a signal line structure, comprising: a medium substrate; and a first signal line and a second signal line arranged on the medium substrate and insulated from each other, wherein one end of each of the first signal line and the second signal line is formed into an input port and a through port respectively, and the other end of each of the first signal line and the second signal line is formed into a coupling port and an isolation port respectively; the first signal line comprises a first connecting line and a first ring structure connected to each other, and the second signal line comprises a second connecting line and a second ring structure connected to each other; a part of the first connecting line is arranged inside the second ring structure and forms a two-side coupling circuit with the part of the first connecting line; and a part of the second connecting line is arranged inside the first ring structure and forms a two-side coupling circuit with the part of the second connecting line.

2. The directional coupler of claim 1, wherein, The number of the first ring structure and the second ring structure is at least one; the first connecting line comprises a first connecting segment, a first coupling segment and a first bridge circuit, the first connecting segment is arranged outside the second ring structure, and the first coupling segment is arranged inside the second ring structure one by one; one of the first coupling segments is bridged with the first connecting segment through the first bridge circuit; the second connecting line comprises a second connecting segment, a second coupling segment and a second bridge circuit, the second connecting segment is arranged outside the first ring structure, and the second coupling segment is arranged inside the first ring structure one by one; one of the second coupling segments is bridged with the second connecting segment through the second bridge circuit.

3. The directional coupler of claim 2, wherein, When the number of the first ring structure and the second ring structure is multiple; each of the first coupling segments is bridged through the first bridge circuit, and each of the second coupling segments is bridged through the second bridge circuit.

4. The directional coupler of claim 2 or 3, wherein, the first bridge circuit comprises a first bridge metal and two first metallized holes arranged at intervals, the two first metallized holes penetrate the medium substrate, the first bridge metal is arranged on a side of the medium substrate away from the first signal line and electrically connects the two first metallized holes; the second bridge circuit comprises a second bridge metal and two second metallized holes arranged at intervals, the two second metallized holes penetrate the medium substrate, the second bridge metal is arranged on a side of the medium substrate away from the second signal line and electrically connects the two second metallized holes.

5. The directional coupler of claim 2, wherein, the first ring structure comprises two first sub-segments arranged oppositely and parallel to each other, and the second ring structure comprises two second sub-segments arranged oppositely and parallel to each other; the second coupling segment is arranged at intervals and parallel to the two first sub-segments of the first ring structure to form a two-side coupling circuit with the first ring structure, and the first coupling segment is arranged at intervals and parallel to the two second sub-segments of the second ring structure to form a two-side coupling circuit with the second ring structure.

6. The directional coupler of claim 5, wherein, the width of the first sub-segment is smaller than the width of the first connecting segment, and the width of the second sub-segment is smaller than the width of the second connecting segment.

7. The directional coupler of claim 5, wherein, one of the two first connection sections connected with the first coupling section is connected with the first ring structure, and the other of the two first connection sections forms one of the ports of the first signal line at one end away from the first coupling section; one of the two second connection sections connected with the second coupling section is connected with the second ring structure, and the other of the two second connection sections forms one of the ports of the second signal line at one end away from the second coupling section.

8. The directional coupler of claim 7, wherein, The first ring structure and the second ring structure are arranged staggered in the first direction and the second direction. The first sub-section and the second sub-section both extend in the first direction. The first direction and the second direction are perpendicular to each other and both are parallel to the dielectric substrate.

9. The directional coupler of claim 8, wherein, When the number of the first ring structures is multiple, the multiple first ring structures are arranged in a row along the second direction and are electrically connected with each other; and when the number of the second ring structures is multiple, the multiple second ring structures are arranged in a row along the second direction and are electrically connected with each other.

10. The directional coupler of claim 5, wherein, When the number of the first ring structure and the number of the second ring structure are both one, the length of the first sub-section and the length of the second sub-section are both in the range of λ / 16-λ / 8; When the number of the first ring structure and the number of the second ring structure are both two, the length of the first sub-section and the length of the second sub-section are both in the range of λ / 32-λ / 16; wherein λ is the center frequency of the electromagnetic wave.

11. An antenna, characterized by The directional coupler comprises the directional coupler according to any one of claims 1-10.

12. The antenna according to claim 11, characterized in that, Further comprising a phase shifter, a first column of oscillators and a second column of oscillators; the feeding end of one of the oscillators in the first column of oscillators is connected to the input port of the directional coupler; the feeding end of one of the oscillators in the second column of oscillators is connected to the isolation port of the directional coupler.

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