A port mutual coupling suppression device of a coupled-fed dual-polarized microstrip antenna
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- NANJING UNIV
- Filing Date
- 2026-06-11
- Publication Date
- 2026-07-21
Smart Images
Figure CN122436701A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of communication equipment technology, and in particular to a port mutual coupling suppression device for a coupled-fed dual-polarized microstrip antenna. Background Technology
[0002] In high-speed information communication systems, dual-polarized antennas can provide two orthogonal independent communication channels, significantly improving system communication efficiency. Currently, polarization multiplexing technology based on dual-polarized antennas has become an important means of increasing the scale of wireless communication. In modern radar technology, dual-polarized antennas utilize the orthogonal characteristics of polarization to obtain more target feature information for the radar system, effectively improving the radar's ability to identify detected and tracked targets and enhancing the overall performance of the radar system. Simultaneously, in information communication and radar systems, a wider bandwidth provides a larger signal loading space for the communication channel, offering richer target feature information for the radar to acquire. In broadband antenna research, the method of achieving broadband antenna operation through coupled feeding is an effective approach and is therefore widely used in the development of communication and radar antenna systems.
[0003] Microstrip antennas, as an important form of communication and radar antennas, are widely used in related systems. For applications requiring dual polarization and broadband connectivity, coupled-fed dual-polarized microstrip antennas have become a hot application area. In these antennas, due to the close distance between the dual-polarized feed lines, the coupling between the two feed ends is significant, which greatly affects antenna performance. For example, in communication systems, port coupling prevents two communication channels from operating independently, resulting in information mutual coupling between channels, degrading the quality of polarization-multiplexed communication or even rendering it inoperable. Similarly, in radar systems, port coupling can confuse the target feature information obtained by dual polarization, making it impossible for the radar to identify and track targets based on this feature information. Furthermore, within the antenna system itself, port coupling increases the reflected energy at the ports, causing them to malfunction or even damage the signal transmission module. Therefore, port coupling suppression in coupled-fed dual-polarized microstrip antennas is crucial for the design and development of this type of antenna. Currently, methods such as electromagnetic isolation, coupling energy absorption, and coupling suppression metasurfaces are commonly used. These methods, with appropriate parameter design, can effectively suppress port coupling.
[0004] However, the aforementioned coupling suppression structures are mostly strong resonant structures, and their suppression effect has a limited operating bandwidth. Furthermore, coupling suppression structures are difficult to install, especially as the antenna operating frequency increases, making installation increasingly difficult. Additionally, coupling suppression structures can adversely affect antenna performance, such as compromising the antenna's matching performance or reducing its radiation efficiency. Moreover, the complexity of installing coupling suppression structures reduces the safety of the antenna system design and increases the cost of the antenna system. Summary of the Invention
[0005] This application provides a port mutual coupling suppression device for coupled-fed dual-polarized microstrip antennas to solve the technical problems of existing coupled-fed dual-polarized microstrip antennas having difficult-to-install port decoupling structures, complex structures, significant impact on antenna performance, and high costs.
[0006] This application provides a port mutual coupling suppression device for a coupled-fed dual-polarized microstrip antenna, which consists of a dual-polarized coupled-fed transmission line and a mutual coupling suppression transmission line; The dual-polarized coupled feed transmission line consists of two coupled feed transmission lines; the two coupled feed transmission lines are perpendicular to each other; one end of the coupled feed transmission line is connected to the dual-polarized feed interface, and the other end of the coupled feed transmission line is an open-circuit terminal, which is used to couple the electromagnetic energy fed into the dual-polarized feed interface to the radiating antenna. The mutual coupling suppression transmission line is a single transmission line; the mutual coupling suppression transmission line is connected to the dual-polarization coupled feed transmission line, and the connection point between the mutual coupling suppression transmission line and the dual-polarization coupled feed transmission line is perpendicular to the dual-polarization coupled feed transmission line.
[0007] In some embodiments, the dual-polarized coupled power supply transmission line is in the form of a dual-layer microstrip; the dual-polarized coupled power supply transmission line is printed on the upper metal layer of the dielectric substrate, and a metal backplate is printed on the lower metal layer of the dielectric substrate.
[0008] In some embodiments, the open-circuit terminal is connected to a U-shaped patch, the opening of which is located on the side away from the coupled power supply transmission line; the opening of the U-shaped patch is perpendicular to the direction of the coupled power supply transmission line.
[0009] In some embodiments, the U-shaped patch is used to ensure impedance matching between the two coupled power supply transmission lines.
[0010] In some embodiments, the mutual coupling suppression transmission line is in the form of a double-layer microstrip; the mutual coupling suppression transmission line is printed on the upper metal layer of the dielectric substrate, and a metal backplate is printed on the lower metal layer of the dielectric substrate.
[0011] In some embodiments, the length of the mutual coupling suppression transmission line is determined based on the coupling phase between the two coupled feed transmission lines.
[0012] In some embodiments, the phase difference formed by the mutual coupling suppression transmission line is π different from the mutual coupling phase difference between the two coupled feed transmission lines, such that the mutual coupling electromagnetic wave vectors formed by the mutual coupling suppression transmission line and the two coupled feed transmission lines cancel each other out.
[0013] In some embodiments, the width of the mutual coupling suppression transmission line is determined based on the impedance ratio of the mutual coupling suppression transmission line to the impedance of the dual-polarized coupled feed transmission line, such that the mutual coupling amplitude formed by the mutual coupling suppression transmission line is equal to the mutual coupling amplitude between the two coupled feed transmission lines.
[0014] This application provides a port mutual coupling suppression device for a coupled-fed dual-polarized microstrip antenna, comprising a dual-polarized coupled-fed transmission line and a mutual coupling suppression transmission line. The dual-polarized coupled-fed transmission line consists of two coupled-fed transmission lines perpendicular to each other. One end of each coupled-fed transmission line is connected to a dual-polarized feed interface, and the other end is an open-circuit terminal used to couple the electromagnetic energy fed into the dual-polarized feed interface to the radiating antenna. The mutual coupling suppression transmission line is a single-path transmission line connected to the dual-polarized coupled-fed transmission line, with the connection point perpendicular to the dual-polarized coupled-fed transmission line. This overcomes the problems of difficult port decoupling structures, complex structures, significant impact on antenna performance, and high costs associated with coupled-fed dual-polarized microstrip antennas. Attached Figure Description
[0015] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0016] Figure 1 This is a schematic diagram of the port mutual coupling suppression device for the coupled-fed dual-polarized microstrip antenna in this application; Figure 2 This is a side view of the antenna as a whole, showing the port mutual coupling suppression structure of the coupled-fed dual-polarized microstrip antenna in this application. Figure 3 The diagram shows the mutual coupling curves between the two polarization ports added to the mutual coupling suppression transmission line in this application.
[0017] Explanation of reference numerals in the attached figures: 1-Dual-polarized coupled power supply transmission line; 11-Coupled power supply transmission line; 2-Mutual coupling suppression transmission line; 3-Dual-polarized power supply interface; 4-Dielectric substrate; 5-Metal backplane; 6-U-shaped patch. Detailed Implementation
[0018] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.
[0019] In some technologies, the port decoupling structure of coupled-fed dual-polarized microstrip antennas is difficult to implement, complex in structure, has a significant impact on antenna performance, and is costly. To address this technical problem, this application provides a port mutual coupling suppression device for coupled-fed dual-polarized microstrip antennas. The port mutual coupling suppression device for coupled-fed dual-polarized microstrip antennas is described below: This application provides a port mutual coupling suppression device for a coupled-fed dual-polarized microstrip antenna, which consists of a dual-polarized coupled-fed transmission line 1 and a mutual coupling suppression transmission line 2.
[0020] The dual-polarized coupled feed transmission line 1 is composed of two coupled feed transmission lines 11; the two coupled feed transmission lines 11 are perpendicular to each other; one end of the coupled feed transmission line 11 is connected to the dual-polarized feed interface 3, and the other end of the coupled feed transmission line 11 is an open-circuit terminal, which is used to couple the electromagnetic energy fed into the dual-polarized feed interface 3 to the radiating antenna.
[0021] Specifically, the dual-polarized coupled feed transmission line 1 consists of two coupled feed transmission lines 11, which are perpendicularly arranged to feed two independent communication channels orthogonally connected to the dual-polarized antenna. One end of each coupled feed transmission line 11 is connected to the dual-polarized feed interface 3 to receive electromagnetic energy signals from it. The other end of each coupled feed transmission line 11 is an open-circuit terminal, not connected to any load or grounding structure. Utilizing the electromagnetic reflection characteristics of the transmission line end, it effectively couples the electromagnetic energy fed from the dual-polarized feed interface 3 to the connected radiating antenna structure, thereby achieving broadband operation. Furthermore, the dual-polarized coupled feed transmission line 1 is a double-layer microstrip design, with the feed transmission line printed on a metal layer of a dielectric substrate and a metal backplate printed on the lower metal layer to enhance the electromagnetic shielding performance of the feed structure and reduce the impact of external interference on the feed transmission.
[0022] The mutual coupling suppression transmission line 2 is a single transmission line; the mutual coupling suppression transmission line 2 is connected to the dual-polarization coupled power supply transmission line 1, and the connection point between the mutual coupling suppression transmission line 2 and the dual-polarization coupled power supply transmission line 1 is perpendicular to the dual-polarization coupled power supply transmission line 1.
[0023] Specifically, the mutual coupling suppression transmission line 2 is a single transmission line. As the core functional unit for realizing port mutual coupling suppression in this application, it differs from traditional schemes that require complex additional components such as external isolation structures, absorption structures or metasurfaces. It can complete the mutual coupling suppression function with only one independent transmission line, which has the advantages of extremely simple structure and easy processing.
[0024] The mutual coupling suppression transmission line 2 connects to the dual-polarized coupled feed transmission line 1. Specifically, its two ends are connected to two mutually perpendicular coupled feed transmission lines 11, creating an additional electromagnetic energy coupling path between the two feed transmission lines. The connection point between the mutual coupling suppression transmission line 2 and the dual-polarized coupled feed transmission line 1 is perpendicular to the dual-polarized coupled feed transmission line 1, meaning that the direction of the mutual coupling suppression transmission line 2 is orthogonal to both coupled feed transmission lines 11. This perpendicular connection ensures that the new mutual coupling signal introduced by the mutual coupling suppression transmission line 2 and the original mutual coupling signal between the two coupled feed transmission lines 11 form an effective electromagnetic superposition in space, thus laying the physical foundation for subsequent vector cancellation by adjusting the amplitude and phase relationship between the two.
[0025] For example, to overcome the shortcomings and deficiencies of coupled-fed dual-polarized microstrip antennas, such as the difficulty in installing port decoupling structures, complex structures, significant impact on antenna performance, and high costs, this application provides a port mutual coupling suppression device that introduces a new mutual coupling and utilizes the electromagnetic cancellation effect between the new mutual coupling and the original mutual coupling to achieve port mutual coupling suppression. This mutual coupling suppression device has a significant mutual coupling suppression effect, and it is easy to install, has a simple structure, and has minimal impact on the antenna.
[0026] In this embodiment, the dual-polarized coupled power transmission line 1 is in the form of a double-layer microstrip; the dual-polarized coupled power transmission line 1 is printed on the upper metal layer of the dielectric substrate 4, and the lower metal layer of the dielectric substrate 4 is printed with a metal backplate 5.
[0027] In this embodiment, the open-circuit terminal is connected to a U-shaped patch 6, the opening of the U-shaped patch 6 is located on the side away from the coupling power supply transmission line 11; the opening direction of the U-shaped patch 6 is perpendicular to the direction of the coupling power supply transmission line 11.
[0028] In this embodiment, the U-shaped patch 6 is used to ensure impedance matching of both coupled power supply transmission lines 11.
[0029] Specifically, the open-circuit terminal is connected to a U-shaped patch 6, which serves as a matching loading structure at the end of the coupled feed transmission line 11. This is used to compensate for the impedance mismatch caused by electromagnetic energy reflection at the open-circuit terminal, ensuring that the feed transmission lines of both dual-polarized antennas achieve good impedance matching, thereby guaranteeing the normal operation of the antenna port and efficient energy transmission.
[0030] Specifically, the opening of the U-shaped patch 6 is positioned away from the coupled power supply transmission line 11, meaning the opening of the U-shaped patch 6 faces away from the power supply transmission line. This opening orientation design allows the U-shaped patch 6 to effectively adjust the equivalent impedance of the open-circuit terminal through its own resonant characteristics without interfering with the electromagnetic energy transmission of the main path of the power supply transmission line. This achieves impedance matching, reduces port reflection energy, and avoids problems such as the port malfunctioning or even damaging the signal transmission module due to excessive port reflection energy.
[0031] Meanwhile, the opening direction of the U-shaped patch 6 is perpendicular to the direction of the coupled feed transmission line 11. That is, the two arms of the U-shaped patch 6 extend along the extension direction of the coupled feed transmission line 11, while the opening faces outward in a direction perpendicular to the feed transmission line. This vertical arrangement is consistent with the overall orthogonal architecture of the dual-polarized coupled feed transmission line 1, which can avoid additional unnecessary coupling between the U-shaped patch 6 and the feed transmission line, and also make the resonant field distribution generated by the U-shaped patch 6 compatible with the operating mode of the radiating antenna. Thus, while achieving impedance matching, it minimizes the adverse effects on the antenna radiation performance.
[0032] Furthermore, the U-shaped patch 6 is also processed in the form of a double-layer microstrip, which is printed on the metal layer of the dielectric substrate and the metal backplate 5 is printed on the lower metal layer. This is consistent with the structure of the dual-polarization coupled feed transmission line 11 and the mutual coupling suppression transmission line 2, ensuring the process compatibility of the entire antenna feed system and reducing the processing complexity and manufacturing cost.
[0033] In this embodiment, the mutual coupling suppression transmission line 2 is in the form of a double-layer microstrip; the mutual coupling suppression transmission line 2 is printed on the upper metal layer of the dielectric substrate 4, and the lower metal layer of the dielectric substrate 4 is printed with a metal backplate 5.
[0034] In this embodiment, the length of the mutual coupling suppression transmission line 2 is determined based on the coupling phase between the two coupled feed transmission lines 11.
[0035] In this embodiment, the phase difference formed by the mutual coupling suppression transmission line 2 is π different from the mutual coupling phase difference between the two coupled feed transmission lines 11, so that the mutual coupling electromagnetic wave vectors formed by the mutual coupling suppression transmission line 2 and the two coupled feed transmission lines 11 cancel each other out.
[0036] Furthermore, the mutual coupling suppression transmission line 2 also adopts a double-layer microstrip form, which is printed on the metal layer of the dielectric substrate, with a metal backplate 5 printed on the lower metal layer, consistent with the structure of the dual-polarized coupled feed transmission line 1, to ensure the process compatibility and electromagnetic consistency of the entire feed system. Simultaneously, the length of the mutual coupling suppression transmission line 2 is determined based on the coupling phase between the two coupled feed transmission lines before the addition of the mutual coupling suppression transmission line, ensuring that the transmission phase difference between the two is π; the width of the mutual coupling suppression transmission line 2 is determined based on the coupling amplitude between the two coupled feed transmission lines before the addition of the mutual coupling suppression transmission line, ensuring that the transmission amplitudes formed by the two are the same, thereby ensuring that the newly introduced mutual coupling is equal in amplitude and opposite in phase to the original mutual coupling, ultimately achieving electromagnetic cancellation and achieving the purpose of port mutual coupling suppression.
[0037] In this embodiment, the width of the mutual coupling suppression transmission line 2 is determined according to the impedance ratio of the mutual coupling suppression transmission line 2 to the dual-polarization coupled feed transmission line 1, such that the mutual coupling amplitude formed by the mutual coupling suppression transmission line 2 is equal to the mutual coupling amplitude between the two coupled feed transmission lines 11.
[0038] Specifically, the width of the mutual coupling suppression transmission line 2 is determined based on the impedance ratio between the mutual coupling suppression transmission line 2 and the dual-polarized coupled feed transmission line 1. This design principle is a key step in achieving precise matching of the amplitudes of the new and old mutual couplings and ultimately achieving electromagnetic cancellation. Specifically, since the two coupled feed transmission lines 11 are physically close, electromagnetic coupling inevitably exists between them. The amplitude of this coupling is determined by the structural parameters and relative positions of the two transmission lines. To effectively suppress this harmful mutual coupling, the mutual coupling suppression transmission line 2 introduced in this application must generate a new mutual coupling signal with completely equal amplitude between the two coupled feed transmission lines 11 in order to achieve vector cancellation under subsequent phase modulation. Therefore, the width of the mutual coupling suppression transmission line 2 needs to be precisely calculated and designed based on its impedance ratio with the dual-polarized coupled feed transmission line 1. By adjusting the width, the characteristic impedance of the mutual coupling suppression transmission line 2 is changed, thereby controlling the mutual coupling strength it generates between the two coupled feed transmission lines 11, making it strictly equal to the original mutual coupling amplitude.
[0039] Furthermore, while ensuring that the mutual coupling amplitude formed by the mutual coupling suppression transmission line 2 is equal to the mutual coupling amplitude between the two coupled feed transmission lines 11, the length of the mutual coupling suppression transmission line 2 also needs to be determined based on the coupling phase between the two coupled feed transmission lines 11 before the addition of the mutual coupling suppression transmission line, so that the transmission phase difference between the two is π, thereby ensuring that the newly introduced mutual coupling is the same in amplitude and opposite in phase as the original mutual coupling, and the two cancel each other out in vector after superposition, ultimately achieving efficient suppression of port mutual coupling.
[0040] Furthermore, since the width and length of the mutual coupling suppression transmission line 2 are independently controlled by two independent parameters, mutual coupling amplitude and mutual coupling phase, the design has good decoupling and flexibility. Designers can optimize and adjust the amplitude and phase separately without mutual interference. This is also a concrete manifestation of the advantages of the present application, which is simple in structure and easy to add.
[0041] For example, the fabrication process of the port mutual coupling suppression device of the coupled-fed dual-polarized microstrip antenna specifically includes the following steps: Step 1: Fabrication of metal backplane and dual-polarized coupled power transmission line: First, a metal backplane 5 is printed on the lower metal layer of the double-layer microstrip dielectric board. This metal backplane 5 serves as the reference ground plane for the entire power supply system, providing a stable electromagnetic reference plane and shielding protection for the upper transmission lines.
[0042] Then, two mutually perpendicular dual-polarized coupled feed transmission lines 1 are designed and fabricated on the metal layer of the dielectric substrate. Each dual-polarized coupled feed transmission line 1 consists of two coupled feed transmission lines 11. The two coupled feed transmission lines 11 maintain a strictly perpendicular spatial relationship to achieve the feeding function of two orthogonal independent communication channels of the dual-polarized antenna. One end of each coupled feed transmission line 11 is connected to the dual-polarized feed interface 3 to receive electromagnetic energy signals from the external system; the other end is set as an open-circuit terminal, which is not connected to any load or grounding structure. It utilizes the electromagnetic reflection characteristics of the transmission line end to effectively couple the electromagnetic energy fed into the dual-polarized feed interface 3 to the connected radiating antenna structure, thereby realizing the wideband operating characteristics of the antenna.
[0043] Step 2: Adding the U-shaped patch matching structure: A matching U-shaped patch 6 is added to the open-circuit terminal of the dual-polarized coupled feed transmission line 1. The opening of the U-shaped patch 6 is located away from the coupled feed transmission line 11, and the opening direction of the U-shaped patch 6 is perpendicular to the direction of the coupled feed transmission line 11. By precisely adjusting the dimensional parameters of the U-shaped patch 6, good impedance matching is ensured for the coupled feed transmission lines 11 of both dual-polarized antennas. This effectively reduces the port reflection energy caused by electromagnetic energy reflection at the open-circuit terminal, avoiding the problem of excessive port reflection energy causing the port to malfunction or even damage the signal transmitting module, thus ensuring the normal operation of the antenna port and efficient energy transmission.
[0044] Step 3: Testing and obtaining mutual coupling parameters: Full-wave simulation analysis was performed using electromagnetic simulation software, or actual testing was conducted on the fabricated antenna feed structure using a vector network analyzer to obtain the mutual coupling parameters between the two dual-polarized coupled feed transmission lines 11 before the addition of the mutual coupling suppression transmission line 2. These mutual coupling parameters mainly include two key indicators: first, the mutual coupling phase, i.e., the phase information of the mutual coupling signal between the two coupled feed transmission lines 11, which directly determines the required length parameter of the subsequent mutual coupling suppression transmission line 2; and second, the mutual coupling amplitude, i.e., the magnitude of the mutual coupling signal between the two coupled feed transmission lines 11, which directly determines the required width parameter of the subsequent mutual coupling suppression transmission line 2. Accurate acquisition of these mutual coupling parameters is a crucial prerequisite for ensuring that the subsequent mutual coupling suppression transmission line 2 can achieve precise amplitude-phase matching and electromagnetic cancellation.
[0045] Step 4: Connection and parameter determination of the mutual coupling suppression transmission line: Based on the mutual coupling parameters obtained in step three above, a mutual coupling suppression transmission line 2 is connected between the two dual-polarized coupled transmission lines 11. The mutual coupling suppression transmission line 2 is a single transmission line, with both ends connected to the two mutually perpendicular coupled transmission lines 11. The connection points of the mutual coupling suppression transmission line 2 and the coupled transmission lines 11 are perpendicular to each other, meaning the direction of the mutual coupling suppression transmission line 2 is orthogonal to both coupled transmission lines 11. This perpendicular connection ensures that the new mutual coupling signal introduced by the mutual coupling suppression transmission line 2 and the existing mutual coupling signal between the two coupled transmission lines 11 form an effective electromagnetic superposition in space.
[0046] The length of the mutual coupling suppression transmission line 2 is determined based on the mutual coupling phase between the two coupled feed transmission lines 11 obtained in step three, so that the transmission phase difference formed by the mutual coupling suppression transmission line 2 is π different from the original mutual coupling phase, thereby ensuring that the newly introduced mutual coupling is completely opposite to the original mutual coupling in phase.
[0047] It is worth noting that the width of the mutual coupling suppression transmission line 2 is determined based on the mutual coupling amplitude between the two coupled feed transmission lines 11 obtained in step three. Specifically, it is calculated based on the impedance ratio between the mutual coupling suppression transmission line 2 and the dual-polarized coupled feed transmission line 1, so that the mutual coupling amplitude excited by the mutual coupling suppression transmission line 2 between the two coupled feed transmission lines 11 is strictly equal to the original mutual coupling amplitude.
[0048] Through the above steps, the newly introduced mutual coupling has the same amplitude and opposite phase to the original mutual coupling. When superimposed, they completely cancel each other out in the vector direction, ultimately achieving efficient suppression of port mutual coupling in coupled-fed dual-polarized microstrip antennas. This process is entirely based on a double-layer microstrip board, with all structures implemented through printing technology. No other complex external structures are required, offering significant advantages such as ease of installation, simple structure, and low cost. It is particularly suitable for mutual coupling suppression in high-frequency antenna systems.
[0049] This application provides a port mutual coupling suppression device for coupled-fed dual-polarized microstrip antennas. Current port mutual coupling suppression schemes mainly employ electromagnetic isolation structures, coupled energy absorption structures, and coupled suppression metasurfaces to achieve port mutual coupling suppression. While these methods can effectively suppress port coupling to a certain extent with appropriate parameter design, they still face several insurmountable problems in practical applications: Firstly, these coupling suppression structures are mostly strong resonant structures, and their suppression effect has a very limited operating bandwidth, making it difficult to meet the urgent demand for broadband operation in modern communication and radar systems. Secondly, the installation of coupling suppression structures is difficult, especially as antenna operating frequencies continue to increase and the physical size of antenna systems shrinks, making the installation of traditional mutual coupling structures increasingly challenging. Furthermore, the introduction of coupling suppression structures can adversely affect the antenna's performance, such as compromising matching performance or reducing radiation efficiency. Simultaneously, the installation process for coupling suppression structures is complex, not only reducing the design safety of the antenna system but also significantly increasing the overall manufacturing cost.
[0050] Unlike the aforementioned solutions, this application does not require any external structures such as mutual coupling isolation structures, mutual coupling absorption structures, or mutual coupling suppression metasurfaces. Instead, it innovatively introduces a new mutual coupling path, namely the mutual coupling suppression transmission line 2, to construct an additional electromagnetic energy coupling channel between the two coupled feed transmission lines 11. By precisely controlling the amplitude and phase relationship between this new mutual coupling and the original mutual coupling between the two coupled feed transmission lines 11, the two are completely canceled in vector terms, thereby achieving the purpose of port mutual coupling suppression. Based on the above technical principles, the port mutual coupling suppression device proposed in this application has outstanding advantages such as simple structure, minimal impact on antenna radiation performance, and low cost.
[0051] It is worth noting that with the rapid development of high-speed information communication systems and new radar technologies, the operating frequency of antenna systems is increasing daily, and the corresponding antenna system size is also shrinking. Under this trend, current mutual coupling suppression structures, due to their complex structure and large size, are becoming increasingly difficult to install, and in many high-frequency scenarios, they are almost impossible to install. However, the mutual coupling suppression device of this application requires no external structures; port mutual coupling suppression can be achieved simply by connecting a single mutual coupling suppression transmission line 2 between two mutually perpendicular coupled feed transmission lines 11. Its structure is extremely simple, and its manufacturing process is completely consistent with that of the feed transmission lines, both based on the printing process of a double-layer microstrip board, without adding any additional complex processing steps. Therefore, the ease of installation of this application makes it more applicable and valuable in port mutual coupling suppression applications of high-frequency antenna systems, effectively solving the technical problem of the difficulty in installing mutual coupling suppression structures in high-frequency antenna systems.
[0052] The above detailed embodiments further illustrate the purpose, technical solution, and beneficial effects of the embodiments of this application. It should be understood that the above are merely specific embodiments of the embodiments of this application and are not intended to limit the protection scope of the embodiments of this application. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solutions of the embodiments of this application should be included within the protection scope of the embodiments of this application.
Claims
1. A port mutual coupling suppression device for a coupled-fed dual-polarized microstrip antenna, characterized in that, It consists of a dual-polarized coupled feed transmission line (1) and a mutual coupling suppression transmission line (2); The dual-polarized coupled feed transmission line (1) is composed of two coupled feed transmission lines (11); the two coupled feed transmission lines (11) are perpendicular to each other; one end of the coupled feed transmission line (11) is connected to the dual-polarized feed interface (3), and the other end of the coupled feed transmission line (11) is an open-circuit terminal, which is used to couple the electromagnetic energy fed into the dual-polarized feed interface (3) to the radiating antenna; The mutual coupling suppression transmission line (2) is a single transmission line; the mutual coupling suppression transmission line (2) is connected to the dual-polarization coupled power supply transmission line (1), and the connection between the mutual coupling suppression transmission line (2) and the dual-polarization coupled power supply transmission line (1) is perpendicular to the dual-polarization coupled power supply transmission line (1).
2. The port mutual coupling suppression device for a coupled-fed dual-polarized microstrip antenna according to claim 1, characterized in that, The dual-polarized coupled power transmission line (1) is in the form of a double-layer microstrip; the dual-polarized coupled power transmission line (1) is printed on the upper metal layer of the dielectric substrate (4), and the lower metal layer of the dielectric substrate (4) is printed with a metal backplate (5).
3. The port mutual coupling suppression device for a coupled-fed dual-polarized microstrip antenna according to claim 1, characterized in that, The open-circuit terminal is connected to a U-shaped patch (6), the opening direction of which is located away from the coupled power supply transmission line (11); the opening direction of the U-shaped patch (6) is perpendicular to the direction of the coupled power supply transmission line (11).
4. The port mutual coupling suppression device for a coupled-fed dual-polarized microstrip antenna according to claim 3, characterized in that, The U-shaped patch (6) is used to ensure impedance matching of both coupled power supply transmission lines (11).
5. The port mutual coupling suppression device for a coupled-fed dual-polarized microstrip antenna according to claim 1, characterized in that, The mutual coupling suppression transmission line (2) is in the form of a double-layer microstrip; the mutual coupling suppression transmission line (2) is printed on the upper metal layer of the dielectric substrate (4), and the lower metal layer of the dielectric substrate (4) is printed with a metal backplate (5).
6. The port mutual coupling suppression device for a coupled-fed dual-polarized microstrip antenna according to claim 1, characterized in that, The length of the mutual coupling suppression transmission line (2) is determined based on the coupling phase between the two coupled feed transmission lines (11).
7. The port mutual coupling suppression device for a coupled-fed dual-polarized microstrip antenna according to claim 6, characterized in that, The phase difference formed by the mutual coupling suppression transmission line (2) is π different from the mutual coupling phase difference between the two coupled power supply transmission lines (11), so that the mutual coupling electromagnetic wave vectors formed by the mutual coupling suppression transmission line (2) and the two coupled power supply transmission lines (11) cancel each other out.
8. The port mutual coupling suppression device for a coupled-fed dual-polarized microstrip antenna according to claim 1, characterized in that, The width of the mutual coupling suppression transmission line (2) is determined according to the impedance ratio of the mutual coupling suppression transmission line (2) to the dual-polarization coupled feed transmission line (1), such that the mutual coupling amplitude formed by the mutual coupling suppression transmission line (2) is equal to the mutual coupling amplitude between the two coupled feed transmission lines (11).