Three-frequency dual-polarized antenna with adjacent frequency bands

Abstract

The invention discloses an adjacent-frequency-band triple-frequency dual-polarized antenna, and the antenna comprises an ultra-wideband orthogonal mode coupler which comprises a first circular waveguide, a mode separation cavity, and a second circular waveguide, the mode separation cavity is respectively connected with the first horizontal polarization branch, the second horizontal polarization branch, the first vertical polarization branch and the second vertical polarization branch through a plurality of side surface coupling holes; the high-frequency orthogonal mode coupler comprises a third circular waveguide, a waveguide transition structure and a high-frequency vertical polarization port which are connected in sequence, the waveguide transition structure is connected with the high-frequency horizontal polarization port through a side coupling hole, and the input end of the third circular waveguide is connected with the second circular waveguide; the first duplexer and the second duplexer are respectively used for combining the horizontal polarization branch and the vertical polarization branch; through the compact structure, dual-polarization transmission on three frequency bands of low frequency, intermediate frequency and high frequency can be realized, the space is saved, the utilization of spectrum resources can be effectively expanded, and the communication capacity is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of communication antennas, and in particular to a triple-band dual-polarization antenna in adjacent frequency bands. Background Art

[0002] The rapid development of communications technology, especially the gradual popularization of 5G and 5G+ networks, has placed higher demands on the transmission speed and reliability of microwave antennas. Traditional microwave antennas typically operate in the 6GHz to 42GHz frequency band. While they can provide high transmission reliability, spectrum resources are increasingly scarce, and the transmission bandwidth is relatively low, making it difficult to meet the growing demand for communication capacity. To address this challenge, the industry has proposed a variety of solutions, such as dual-band antennas that combine E-band (71-86GHz) and conventional frequency bands (15 / 18 / 23 / 26 / 28 / 32 / 38GHz), as well as low-band dual-band solutions (such as 4+11GHz, 4+7wGHz, 6+10wGHz, and 7+10wGHz).

[0003] However, these solutions still have certain limitations in terms of transmission distance, weather impact, antenna diameter, etc. For example, although the E-band band can provide a transmission capacity of up to 20Gbps, the transmission distance is short and is greatly affected by weather. And although the low-band dual-band solution can effectively resist multipath fading and other interference, it usually requires a larger antenna diameter and is not suitable for all scenarios. Therefore, developing an antenna technology that can achieve higher transmission capacity and longer transmission distance with limited spectrum resources has become an urgent problem to be solved in the current communications field. Summary of the Invention

[0004] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art. The present invention proposes a three-band dual-polarization antenna in adjacent frequency bands. By adopting key components such as an ultra-wideband orthogonal mode coupler, a high-frequency orthogonal mode coupler, and a duplexer, dual-polarization transmission in the three frequency bands of low frequency, medium frequency, and high frequency is achieved. While saving space, it can effectively expand the utilization of spectrum resources and improve communication capacity.

[0005] An embodiment of the present invention provides a triple-band dual-polarization antenna for adjacent frequency bands, comprising: an ultra-wideband orthogonal mode coupler, comprising a first circular waveguide, a mode separation cavity, and a second circular waveguide connected in sequence, wherein the mode separation cavity is respectively connected to a first horizontal polarization branch, a second horizontal polarization branch, a first vertical polarization branch, and a second vertical polarization branch through a plurality of side coupling holes, the input end of the first circular waveguide is a signal common port, and the output end of the second circular waveguide is a signal main port; a high-frequency orthogonal mode coupler, comprising a third circular waveguide, a waveguide transition structure, and a high-frequency vertical polarization port connected in sequence, the waveguide transition structure is connected to the high-frequency horizontal polarization port through a side coupling hole, and the input end of the third circular waveguide is connected to the signal main port; a first duplexer, comprising a first combining structure, a first low-frequency branch, and a second combining structure. The output ends of the first horizontal polarization branch and the second horizontal polarization branch are connected to the first combining structure, the first combining structure is connected to the first low-frequency branch and the first intermediate frequency branch, the output end of the first low-frequency branch is a low-frequency horizontal polarization port, and the output end of the second low-frequency branch is an intermediate frequency horizontal polarization port; the second duplexer includes a second combining structure, a second low-frequency branch, and a second intermediate frequency branch, the output ends of the first vertical polarization branch and the second vertical polarization branch are connected to the second combining structure, the second combining structure is connected to the second low-frequency branch and the second intermediate frequency branch, the output end of the second low-frequency branch is a low-frequency vertical polarization port, and the output end of the second intermediate frequency branch is an intermediate frequency vertical polarization port.

[0006] In some embodiments, the mode separation cavity is connected to the first horizontal polarization branch through a first side coupling hole, connected to the first vertical polarization branch through a second side coupling hole, connected to the second horizontal polarization branch through a third side coupling hole, and connected to the second vertical polarization branch through a fourth side coupling hole; wherein, the first side coupling hole and the third side coupling hole are relatively arranged on the left and right sides of the mode separation cavity, and the second side coupling hole and the fourth side coupling hole are relatively arranged on the upper and lower sides of the mode separation cavity, and the angle between adjacent polarization branches is 90 degrees.

[0007] In some embodiments, the diameter of the second circular waveguide is smaller than that of the first circular waveguide, and the mode separation cavity includes a multi-segment annular stepped structure with gradually decreasing diameters from the first circular waveguide to the second circular waveguide.

[0008] In some embodiments, each polarization branch includes a multi-gradient ridge waveguide, one end of which is connected to the corresponding side coupling hole, and the other end is provided with multiple gradient spines to form a low-pass filter.

[0009] In some embodiments, the high-frequency orthogonal mode coupler includes a vertical rectangular waveguide and a horizontal rectangular waveguide, the vertical rectangular waveguide is connected to the waveguide transition structure, the output end of the vertical rectangular waveguide is the high-frequency vertical polarization port, the waveguide transition structure is connected to the horizontal rectangular waveguide through a side coupling hole, the output end of the horizontal rectangular waveguide is the high-frequency horizontal polarization port, and the waveguide transition structure includes a multi-section stepped structure that gradually narrows along the direction from the third circular waveguide to the vertical rectangular waveguide.

[0010] In some embodiments, the side coupling hole is a strip-shaped through hole arranged along the signal direction of the mode separation cavity, and the length of the strip-shaped through hole is one quarter of the wavelength of the 7 GHz low-frequency signal.

[0011] In some embodiments, the first combining structure and the second combining structure both include an H-plane 90-degree bend waveguide structure, a three-section twist waveguide structure, and a combiner connected in sequence. The combiner is a common port at the input end of the duplexer, and is used to combine the two signals and transmit them to the corresponding low-frequency branch and intermediate-frequency branch.

[0012] In some embodiments, an arch structure is formed between the low-frequency branch and the intermediate-frequency branch in the first duplexer and the second duplexer, and the arch structure is connected to the combiner. The low-frequency branch and the intermediate-frequency branch are both provided with multiple resonators, and the resonators are cylindrical or square-cylindrical in shape.

[0013] In some embodiments, a CT cross-coupling structure formed by three adjacent resonators connected by metal rods exists in the low-frequency branch, and an adjustment screw is provided at the center of the resonator.

[0014] In some embodiments, a feed source is further included, which is connected to the signal common port. The feed source includes a radiation head, a sub-reflector and a circular waveguide. A conical groove is provided at the bottom end of the radiation head, and the sub-reflector is nested in the conical groove. The top end of the radiation head is inserted into one end of the circular waveguide, and the other end of the circular waveguide is connected to the common port of the mode separation cavity through two interconnected cylindrical cavities.

[0015] According to an embodiment of the present invention, an anti-interference ultra-wideband antenna is provided, which has at least the following beneficial effects: the adjacent frequency band three-band dual-polarization antenna of the present invention forms a five-channel structure by adding a high-frequency channel at the orthogonal mode coupler, which can realize dual-polarization transmission in the three frequency bands of low frequency, medium frequency and high frequency, thereby improving the communication capacity and transmission efficiency of the antenna, improving the isolation between high frequency and medium and low frequency, and effectively reducing the volume of the antenna structure; wherein, the ultra-wideband orthogonal mode coupler includes a first circular waveguide, a mode separation cavity and a second circular waveguide connected in sequence, the mode separation cavity is connected to the first horizontal polarization branch, the second horizontal polarization branch, the first vertical polarization branch and the second vertical polarization branch through multiple side coupling holes, the input end of the first circular waveguide is a signal common port for receiving a mixed signal from the antenna, the ultra-wideband orthogonal mode coupler is used to separate the two polarizations of medium and low frequency and separate the high-frequency signal, and the output end of the second circular waveguide is used as a signal main port for transmitting the separated signal to a subsequent high-frequency orthogonal mode coupler a high-frequency orthogonal-mode coupler, comprising a third circular waveguide, a waveguide transition structure and a high-frequency vertical polarization port connected in sequence, the waveguide transition structure being connected to the high-frequency horizontal polarization port through a side coupling hole, for separating the high-frequency signal to obtain a high-frequency vertically polarized signal and a high-frequency horizontally polarized signal; a first duplexer, comprising a first combining structure, a first low-frequency branch and a first intermediate-frequency branch, for performing frequency band separation on the intermediate and low-frequency signals in the first horizontally polarized branch and the second horizontally polarized branch to obtain corresponding low-frequency horizontally polarized signals and intermediate-frequency horizontally polarized signals; a second duplexer, comprising a second combining structure, a second low-frequency branch and a second intermediate-frequency branch, for performing frequency band separation on the intermediate and low-frequency signals in the first vertically polarized branch and the second vertically polarized branch to obtain corresponding low-frequency vertically polarized signals and intermediate-frequency vertically polarized signals; in summary, the present application realizes dual-polarization transmission in the three frequency bands of low frequency, intermediate frequency and high frequency through the above-mentioned compact structural design, which can effectively expand the utilization of spectrum resources and improve communication capacity while saving space.

[0016] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purposes and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the technical solution of the present invention and do not constitute a limitation to the technical solution of the present invention.

[0018] The present invention will be further described below with reference to the accompanying drawings and examples; Figure 1Schematic diagram of the structure of the ultra-wideband orthogonal mode coupler of the present invention; Figure 2 is a front view of the ultra-wideband orthogonal mode coupler of the present invention; Figure 3 It is a structural schematic diagram of the high frequency orthogonal mode coupler of the present invention; Figure 4 is a schematic structural diagram of the first duplexer in the present invention; Figure 5 It is a schematic structural diagram of the adjacent frequency band triple-band dual-polarization antenna in the present invention; Figure 6 This is another structural diagram of the adjacent frequency band triple-band dual-polarization antenna of the present invention; Figure 7 It is a structural diagram of the feed source in the present invention.

[0019] Reference numerals: 100, ultra-wideband orthogonal mode coupler; 101, first circular waveguide; 102, mode separation cavity; 103, second circular waveguide; 110, signal common port; 120, signal main port; 130, first horizontal polarization branch; 140, second horizontal polarization branch; 150, first vertical polarization branch; 160, second vertical polarization branch; 170, high-frequency orthogonal mode coupler; 180, first duplexer; 190, second duplexer; 201, multi-gradient ridge waveguide; 301, third circular waveguide; 302, waveguide transition structure; 303, vertical rectangular waveguide; 304, horizontal rectangular Waveguide; 310, high-frequency vertical polarization port; 320, high-frequency horizontal polarization port; 401, first low-frequency branch; 402, first intermediate-frequency branch; 403, CT cross-coupling structure; 410, connection end; 420, low-frequency horizontal polarization port; 430, intermediate-frequency horizontal polarization port; 501, H-plane 90-degree bend waveguide structure; 502, three-section twist waveguide structure; 503, combiner; 610, low-frequency vertical polarization port; 620, intermediate-frequency vertical polarization port; 700, feed source; 701, radiation head; 702, secondary reflector; 703, circular waveguide; 704, tapered slot. DETAILED DESCRIPTION

[0020] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it should not be understood as a limitation on the scope of protection of the present invention.

[0021] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. "Any one" refers to one or more, and "at least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and is not to be construed as indicating or implying relative importance, or implicitly indicating the quantity of the indicated technical features, or implicitly indicating the order of the indicated technical features.

[0022] It should be noted that the terms "dispose," "install," and "connect" in the embodiments of the present invention should be interpreted broadly. Those skilled in the art can reasonably determine the specific meanings of these terms in the embodiments of the present invention based on the specific content of the technical solution. For example, the term "connect" can refer to mechanical connection, electrical connection, or communication; it can be direct connection or indirect connection through an intermediary.

[0023] It should be noted that the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0024] The rapid development of communications technology, especially the increasing adoption of 5G and 5G+ networks, is placing higher demands on the transmission speed and reliability of microwave antennas. Traditional microwave antennas typically operate in the 6GHz to 42GHz frequency band. While they offer high transmission reliability, spectrum resources are increasingly scarce, and transmission bandwidth is relatively low, making it difficult to meet the growing demand for communication capacity. To address this challenge, the industry has proposed a variety of solutions, such as dual-band antennas that combine E-band (71-86GHz) with conventional frequency bands (15 / 18 / 23 / 26 / 28 / 32 / 38GHz), as well as low-band dual-band solutions (such as 4+11GHz, 4+7GHz, 6+10GHz, and 7+10GHz). However, these solutions still have certain limitations in terms of transmission distance, weather impact, antenna diameter, etc. For example, although the E-band band can provide a transmission capacity of up to 20Gbps, the transmission distance is short and is greatly affected by weather. And although the low-band dual-band solution can effectively resist multipath fading and other interference, it usually requires a larger antenna diameter and is not suitable for all scenarios. Therefore, developing an antenna technology that can achieve higher transmission capacity and longer transmission distance with limited spectrum resources has become an urgent problem to be solved in the current communications field.

[0025] Based on this, the purpose of the present invention is to solve at least one of the technical problems existing in the prior art. The present invention proposes a three-band dual-polarization antenna in adjacent frequency bands. By adopting key components such as an ultra-wideband orthogonal mode coupler, a high-frequency orthogonal mode coupler and a duplexer, dual-polarization transmission in the three frequency bands of low frequency, medium frequency and high frequency is achieved. While saving space, it can effectively expand the utilization of spectrum resources and improve communication capacity.

[0026] The present invention will be further described below with reference to the accompanying drawings and examples; refer to Figures 1 to 7 , Figure 1 Schematic diagram of the structure of the ultra-wideband orthogonal mode coupler of the present invention; Figure 2 is a front view of the ultra-wideband orthogonal mode coupler of the present invention; Figure 3 It is a structural schematic diagram of the high frequency orthogonal mode coupler of the present invention; Figure 4 is a schematic structural diagram of the first duplexer in the present invention; Figure 5 It is a schematic structural diagram of the adjacent frequency band triple-band dual-polarization antenna in the present invention; Figure 6 This is another structural diagram of the adjacent frequency band triple-band dual-polarization antenna of the present invention; Figure 7 It is a structural diagram of the feed source in the present invention.

[0027] like Figure 5 and Figure 6As shown, an embodiment of the present invention provides a triple-band dual-polarization antenna for adjacent frequency bands, including: an ultra-wideband orthogonal mode coupler 102, including a first circular waveguide 101, a mode separation cavity 102, and a second circular waveguide 103 connected in sequence, wherein the mode separation cavity 102 is respectively connected to a first horizontal polarization branch 130, a second horizontal polarization branch 140, a first vertical polarization branch 150, and a second vertical polarization branch 160 through a plurality of side coupling holes, the input end of the first circular waveguide 101 is a signal common port 110, and the output end of the second circular waveguide 103 is a signal main port 120; a high-frequency orthogonal mode coupler 170, including a third circular waveguide 301, a waveguide transition structure 302, and a high-frequency vertical polarization port 310 connected in sequence, the waveguide transition structure 302 is connected to the high-frequency horizontal polarization port 320 through a side coupling hole, and the input end of the third circular waveguide 301 is connected to the signal main port 120. ; The first duplexer 180 includes a first combining structure, a first low-frequency branch 401 and a first intermediate frequency branch 402. The output ends of the first horizontal polarization branch 130 and the second horizontal polarization branch 140 are connected to the first combining structure. The first combining structure is connected to the first low-frequency branch 401 and the first intermediate frequency branch 402. The output end of the first low-frequency branch 401 is a low-frequency horizontal polarization port 420, and the output end of the second low-frequency branch is an intermediate frequency horizontal polarization port 430. The second duplexer 190 includes a second combining structure, a second low-frequency branch and a second intermediate frequency branch. The output ends of the first vertical polarization branch 150 and the second vertical polarization branch 160 are connected to the second combining structure. The second combining structure is connected to the second low-frequency branch and the second intermediate frequency branch. The output end of the second low-frequency branch is a low-frequency vertical polarization port 610, and the output end of the second intermediate frequency branch is an intermediate frequency vertical polarization port 620.

[0028] It can be understood that the adjacent frequency band three-band dual-polarization antenna of the present invention forms a five-channel structure by adding a high-frequency channel at the orthogonal mode coupler, which can realize dual-polarization transmission in the three frequency bands of low frequency, medium frequency and high frequency, thereby improving the communication capacity and transmission efficiency of the antenna, improving the isolation between high frequency and medium and low frequency, and effectively reducing the volume of the antenna structure; wherein, the ultra-wideband orthogonal mode coupler 102 is used to separate the two polarizations of medium and low frequency and separate the high-frequency signal, and the output end of the second circular waveguide 103 serves as the signal main port 120, which is used to transmit the separated signal to the subsequent high-frequency orthogonal mode coupler 170; the high-frequency orthogonal mode coupler 170 is used to separate the high-frequency signal and obtain a high-frequency vertical Straight polarization signal and high-frequency horizontal polarization signal; the first duplexer 180 is used to perform frequency band separation on the medium and low frequency signals in the first horizontal polarization branch 130 and the second horizontal polarization branch 140 to obtain corresponding low-frequency horizontal polarization signal and medium-frequency horizontal polarization signal; the second duplexer 190 is used to perform frequency band separation on the medium and low frequency signals in the first vertical polarization branch 150 and the second vertical polarization branch 160 to obtain corresponding low-frequency vertical polarization signal and medium-frequency vertical polarization signal; in summary, the present application realizes dual-polarization transmission in the three frequency bands of low frequency, medium frequency and high frequency through the above-mentioned compact structure design, which can save space while effectively expanding the utilization of spectrum resources and improving communication capacity.

[0029] It is worth noting that the present invention upgrades existing dual-band dual-polarization antennas by adding a third frequency band, expanding from two frequency bands, 6 GHz and 7 GHz, to three frequency bands, 6 GHz, 7 GHz, and 10 GHz. This upgrade enables the antenna to perform dual-polarization transmission over a wider spectrum, significantly improving communication capacity. Furthermore, since the 6 GHz and 7 GHz signals are separated by only 0.1 GHz, with a relative bandwidth of approximately 1.5%, this places extremely high demands on traditional duplexer technology, posing significant challenges in theory, design, process, and tolerance. However, the present invention achieves stable dual-polarization transmission across three frequency bands. Furthermore, based on the aforementioned structure, the antenna aperture of the present invention ranges from 0.3 m to 1.8 m, meeting the requirements of transmission over varying distances and demonstrating strong applicability and flexibility. By enabling transmission across three frequency bands on a single antenna, the present invention not only increases communication capacity but also effectively reduces tower rental and manufacturing costs, bringing them to the same level as a single-band antenna. This improves efficiency and cost-effectiveness, offering significant economic advantages for users.

[0030] like Figure 1 and Figure 2As shown, in some embodiments, corresponding to the ultra-wideband orthogonal mode coupler 102, the first circular waveguide 101 serves as the signal entrance, receiving the mixed polarization signal from the antenna, and its input end is defined as the signal common port 110, which is responsible for introducing the unseparated signal into the coupler; the mode separation cavity 102 can effectively separate signals of different polarizations through its internal structure design. The cavity is provided with multiple side coupling holes, which are respectively connected to the first horizontal polarization branch 130, the second horizontal polarization branch 140, the first vertical polarization branch 150 and the second vertical polarization branch 160 to achieve signal separation; the second circular waveguide 103 serves as the output part of the mode separation cavity 102, and its output end is defined as the signal main port 120, which is responsible for transmitting the separated signal to the subsequent high-frequency orthogonal mode coupler 170. The design of the second circular waveguide 103 ensures the stability and low loss of the signal during transmission.

[0031] In some embodiments, corresponding to the high-frequency orthogonal-mode coupler 170, the third circular waveguide 301 receives the signal from the signal main port 120 of the ultra-wideband orthogonal-mode coupler 102, and serves as a transmission channel for the high-frequency signal. The waveguide transition structure 302 connects the third circular waveguide 301 and the high-frequency vertical polarization port 310, and separates the high-frequency horizontal polarization signal through the side coupling hole inside it and transmits it to the high-frequency horizontal polarization port 320. The high-frequency vertical polarization port 310 is specifically used to output high-frequency vertical polarization signals to ensure efficient transmission and separation of high-frequency signals.

[0032] In some embodiments, corresponding to the first duplexer 180, the first combining structure receives signals from the first horizontally polarized branch 130 and the second horizontally polarized branch 140, combines these signals for subsequent separation and transmission. After receiving the signal from the first combining structure, the first low-frequency branch 401 further separates the low-frequency horizontally polarized signal and outputs it through its output port. The first intermediate frequency branch 402 also receives the signal from the first combining structure, separates the intermediate frequency horizontally polarized signal, and outputs it through its output port. Corresponding to the second duplexer 190, the second combining structure is similar to the first duplexer 180, but processes vertically polarized signals. It receives signals from the first vertically polarized branch 150 and the second vertically polarized branch 160 and combines them. After receiving the signal from the second combining structure, the second low-frequency branch separates the low-frequency vertically polarized signal and outputs it through its output port. The second intermediate frequency branch is responsible for separating the intermediate frequency vertically polarized signal and outputting it through its output port.

[0033] Among them, the signal main port 120 of the ultra-wideband orthogonal mode coupler 102 is connected to the third circular waveguide 301 of the high-frequency orthogonal mode coupler 170 through the second circular waveguide 103, ensuring continuous transmission of high-frequency signals. The first duplexer 180 and the second duplexer 190 are respectively connected to the horizontal polarization branch and the vertical polarization branch of the ultra-wideband orthogonal mode coupler 102 through their combining structures to achieve effective signal separation and transmission. Inside the first duplexer 180 and the second duplexer 190, the combining structure is respectively connected to the low-frequency branch and the intermediate-frequency branch, ensuring that signals in different frequency bands can be effectively separated and transmitted to the corresponding ports. Through the above detailed design and connection relationship, the ultra-wideband orthogonal mode coupler 102 of the present application and its related components can achieve efficient separation and transmission of dual-polarization signals in the three frequency bands of low frequency, intermediate frequency and high frequency, meeting the requirements of modern communication systems for high-capacity, long-distance and high-reliability transmission.

[0034] like Figure 1 and Figure 2 As shown, in some embodiments, the mode separation cavity 102 is connected to the first horizontal polarization branch 130 through a first side coupling hole, is connected to the first vertical polarization branch 150 through a second side coupling hole, is connected to the second horizontal polarization branch 140 through a third side coupling hole, and is connected to the second vertical polarization branch 160 through a fourth side coupling hole, so that the mode separation cavity 102 can separate and transmit signals of different polarizations.

[0035] Specifically, the first side coupling hole and the third side coupling hole are relatively arranged on the left and right sides of the mode separation cavity 102, and the second side coupling hole and the fourth side coupling hole are relatively arranged on the upper and lower sides of the mode separation cavity 102 to ensure stable transmission and efficient separation of signals. The angle between adjacent polarization branches is 90 degrees, so that signals of different polarizations do not interfere with each other during transmission, thereby improving signal isolation and transmission efficiency.

[0036] In some embodiments, the operating frequency band of the ultra-wideband orthogonal-mode coupler 102 of the present invention is 5.925 GHz-11.7 GHz. The ultra-wideband orthogonal-mode coupler 102 is different from the current conventional structure. First, it has four coupling ports that are extended and then combined. The use of four ports can effectively reduce losses. The ultra-wideband orthogonal-mode coupler 102 also includes a duplexer function, which can transmit high-frequency 10 GHz signals through the second circular waveguide 103 below, effectively improving circuit efficiency. The four coupling ports on the side are used to transmit low-frequency and medium-frequency information of 6 GHz (5.925 GHz-7.075 GHz) and 7 GHz (7.175 GHz-8.5 GHz). The three frequency bands can be combined together, and the three frequency bands and polarizations can be separated through the ultra-wideband feeding network composed of the orthogonal-mode coupler + duplexer to achieve three-band dual-polarization transmission.

[0037] In some embodiments, the first side coupling hole and the third side coupling hole are arranged relative to each other, so that the first horizontal polarization branch 130 is connected to the mode separation cavity 102 through the first side coupling hole, and the second horizontal polarization branch 140 is connected to the mode separation cavity 102 through the third side coupling hole. The second side coupling hole and the fourth side coupling hole are arranged relative to each other, so that the first vertical polarization branch 150 is connected to the mode separation cavity 102 through the second side coupling hole, and the second vertical polarization branch 160 is connected to the mode separation cavity 102 through the fourth side coupling hole. The angle between adjacent polarization branches is 90 degrees. It can be understood that the transmission paths of the horizontally polarized signal and the vertically polarized signal in the mode separation cavity 102 are perpendicular to each other. This layout prevents signals of different polarizations from interfering with each other during transmission, thereby improving signal isolation and transmission efficiency.

[0038] It is worth noting that through the reasonable layout of the first side coupling hole, the second side coupling hole, the third side coupling hole and the fourth side coupling hole, and the 90-degree angle design between adjacent polarization branches, the mode separation cavity 102 can efficiently separate and transmit signals of different polarizations, so as to optimize the signal transmission path, reduce signal loss and interference during transmission, and improve signal isolation and transmission efficiency, so that the antenna can operate stably in a multi-band, dual-polarization environment, meeting the requirements of modern communication systems for high capacity and high reliability.

[0039] In some embodiments, the diameter of the second circular waveguide 103 is smaller than the diameter of the first circular waveguide 101. This design enables the signal to gradually adapt to the change in waveguide diameter during transmission from the first circular waveguide 101 to the second circular waveguide 103, thereby reducing signal transmission loss and reflection. It can be understood that a smaller waveguide diameter can better match the wavelength of the high-frequency signal, thereby reducing signal attenuation during transmission. In addition, this gradual change in diameter can also reduce the discontinuity of the signal at the waveguide interface, further improving the signal transmission quality.

[0040] In some embodiments, the mode separation cavity 102 includes a multi-section annular stepped structure with a diameter gradually decreasing from the first circular waveguide 101 to the second circular waveguide 103. As the waveguide diameter gradually decreases, the signal propagation path in the cavity also gradually changes. This change helps to separate signals of different polarizations, and the multi-section annular stepped structure can also reduce the reflection and interference of the signal in the cavity, thereby improving the signal transmission efficiency and stability. It can be understood that the presence of the coupling hole will cause discontinuous high-frequency signal transmission and generate high-order mode interference signal transmission. For this purpose, the present application can connect the two sections of circular waveguides through several sections of steps and reduce the diameter of the circular waveguide for high-frequency transmission to achieve the technical effect of reducing high-order modes. In addition, the main port 120 for transmitting the high-frequency signal is extended through a circular waveguide of reduced size after coming out of the mode separation cavity 102.

[0041] In some embodiments, each polarization branch includes a multi-gradient ridge waveguide 201, one end of which is connected to the corresponding side coupling hole, and the other end is provided with multiple gradient spines to form a low-pass filter. This design enables the polarization branch to not only effectively transmit signals but also filter the signals. Specifically, the spine design of the multi-gradient ridge waveguide 201 can form a low-pass filter, which can effectively isolate high-frequency signals and ensure the transmission quality of low-frequency signals. In this way, the polarization branch can effectively filter the signal while transmitting the signal, thereby improving the signal purity and transmission efficiency.

[0042] like Figure 3 As shown, in some embodiments, the high-frequency orthogonal mode coupler 170 includes a vertical rectangular waveguide 303 and a horizontal rectangular waveguide 304, the vertical rectangular waveguide 303 is connected to the waveguide transition structure 302, the output end of the vertical rectangular waveguide 303 is a high-frequency vertical polarization port 310, the waveguide transition structure 302 is connected to the horizontal rectangular waveguide 304 through a side coupling hole, and the output end of the horizontal rectangular waveguide 304 is a high-frequency horizontal polarization port 320; it can be understood that the high-frequency orthogonal mode coupler 170 can efficiently handle the transmission and separation of high-frequency signals, the structural design of the vertical rectangular waveguide 303 and the horizontal rectangular waveguide 304 enables the high-frequency signal to be effectively separated and transmitted within the coupler, and the design of the waveguide transition structure 302 further ensures the smooth transition of the signal between different waveguides, reducing signal reflection and loss.

[0043] In some embodiments, the waveguide transition structure 302 includes a multi-section stepped structure that gradually narrows from the third circular waveguide 301 to the vertical rectangular waveguide 303, so that the waveguide transition structure 302 can more effectively transition and transmit signals; it can be understood that as the waveguide width gradually narrows, the propagation path of the signal within the transition structure also gradually changes. This change helps to reduce signal reflection and loss and improve signal transmission efficiency. The multi-section stepped structure can also reduce the discontinuity of the signal at the waveguide interface, further improving the signal transmission quality.

[0044] In some embodiments, the side coupling hole is a strip-shaped through hole arranged along the signal direction of the mode separation cavity 102, and the length of the strip-shaped through hole is one-quarter wavelength of the 7 GHz low-frequency signal. This design enables the coupling hole to effectively couple the 7 GHz low-frequency signal, ensuring that the low-frequency signal generates a standing wave at the coupling hole, thereby enhancing the signal coupling efficiency.

[0045] like Figure 5 and Figure 6 As shown, in some embodiments, the first combining structure and the second combining structure both include an H-plane 90-degree bend waveguide structure 501, a three-section twist waveguide structure 502, and a combiner 503 connected in sequence; the H-plane 90-degree bend waveguide structure 501 is used to change the propagation direction of the signal so that the signal can be effectively transmitted and separated between different polarization branches; the three-section twist waveguide structure 502 is used to further adjust the phase and amplitude of the signal to ensure that the signal can be effectively combined at the combiner 503. The combiner 503 serves as a common port at the input end of the duplexer and is used to combine the two signals and transmit them to the corresponding low-frequency branch and intermediate-frequency branch. This design not only improves the transmission efficiency of the signal, but also reduces the loss and interference of the signal during the transmission process.

[0046] like Figure 4 As shown, in some embodiments, an arch structure is formed between the low-frequency branch and the intermediate-frequency branch in the first duplexer 180 and the second duplexer 190, and the middle part of the arch structure is connected to the combiner 503 through the connection end 410. The low-frequency branch and the intermediate-frequency branch are both provided with a plurality of resonators, and the shape of the resonators is cylindrical or square. The design of the arch structure enables the low-frequency branch and the intermediate-frequency branch to be effectively separated in space, thereby reducing mutual interference between signals. The setting of the resonator further improves the filtering performance of the branch, ensuring the purity and stability of the signal during transmission. It can be understood that the resonator can effectively suppress unnecessary frequency components, thereby improving the isolation and transmission efficiency of the signal. In some embodiments, the waveguide transition structure 302 includes a multi-section stepped structure that gradually narrows from the third circular waveguide 301 to the vertical rectangular waveguide 303. This design enables the waveguide transition structure 302 to more effectively transition and transmit signals. As the waveguide width gradually narrows, the signal propagation path within the transition structure also gradually changes. This change helps to reduce signal reflection and loss and improve signal transmission efficiency. The multi-section stepped structure can also reduce the discontinuity of the signal at the waveguide interface, further improving the signal transmission quality.

[0047] In some embodiments, a CT cross-coupling structure 403 is present in the low-frequency branch, formed by three adjacent resonators connected by metal rods. An adjustment screw is provided at the center of the resonator. The design of this CT cross-coupling structure 403 enables the low-frequency branch to achieve better filtering performance and signal transmission characteristics. Specifically, the three resonators are connected by the metal rod to form a loop, which can generate the required transmission zero point, thereby improving standing wave performance and reducing loss. The setting of the adjustment screw allows fine-tuning of the resonant frequency of the resonator to optimize signal transmission performance.

[0048] In some embodiments, the low-frequency branch and the intermediate-frequency branch of the first duplexer 180 and the second duplexer 190 can each use 8 resonators, and the resonators are connected by metal rods, wherein the low-frequency branch has 3 resonant columns connected together to form a loop, and the loop is a CT triangular cross-coupling structure; the coupling between the resonators is mainly improved by adjusting the depth of the screws, and reasonable matching of the depth of each screw can optimize and improve the performance of the duplexer until it meets the use requirements; wherein, the duplexer of the present invention can ensure that the isolation between the two frequency bands meets -30dB, the isolation width is 100MHz, the low-frequency port transmission frequency is 5.925-7.075GHz, and the intermediate-frequency port transmission frequency is 7.175-8.5GHz.

[0049] In some embodiments, the multi-gradient ridge waveguide 201 is an asymmetric gradient ridge structure, specifically including: the spine of the ridge waveguide increases gradually along the signal transmission direction, and the ridge height gradually increases from 0.5 mm to 2.0 mm, forming an impedance gradient; a chamfered opening structure is set at the end of the ridge waveguide, and the opening angle is 30°-45°, which is used to suppress high-frequency reflection; adjacent ridge waveguides are connected by a metal diaphragm, and the thickness of the diaphragm is 0.1 the lowest frequency band wavelength λ, which is used to achieve wide-band signal matching, thereby effectively improving the suppression effect.

[0050] In some embodiments, among the three resonators of the CT cross-coupling structure 403, the middle resonator can be cylindrical, and the resonators on both sides can be square columns. The three are connected in series through a U-shaped metal rod. A small cylindrical resonator is nested inside the square column resonator, and the distance between the two is 0.05λ, forming a double coupling; the resonator adjustment screw adopts a tapered thread design, and a polytetrafluoroethylene gasket is embedded in the end of the screw to avoid parasitic capacitance caused by metal contact, thereby optimizing the standing wave ratio of the duplexer and the isolation between segments.

[0051] like Figure 7 As shown, in some embodiments, a feed source 700 is further included, which is connected to the signal common port 110. The feed source 700 includes a radiation head 701, a sub-reflector 702 and a circular waveguide 703. A conical groove 704 is provided at the bottom end of the radiation head, and a sub-reflector is nested in the conical groove. The top end of the radiation head is inserted into one end of the circular waveguide, and the other end of the circular waveguide is connected to the common port of the mode separation cavity 102 through two interconnected cylindrical cavities. This feed source design enables the signal to be efficiently transmitted from the feed source to the mode separation cavity 102, thereby realizing the separation and transmission of signals of different polarizations. The conical groove design of the radiation head helps to improve the radiation efficiency of the signal, and the setting of the sub-reflector can further optimize the signal transmission path and reduce signal loss and interference. The use of the circular waveguide ensures the stability and efficiency of the signal during transmission, thereby improving the performance of the entire antenna system.

[0052] In some embodiments, the ultra-wideband antenna feed of the present invention utilizes a circular waveguide feed, the dimensions of which match the dual-band, dual-polarization feed network of the present invention. The use of a circular waveguide not only improves signal transmission efficiency but also makes the feed structure more compact and stable. The radiating head utilizes PPO material as its base material. PPO material has a very stable dielectric constant (ε = 2.55) and a very low loss tangent, making it well-suited for ultra-wideband feeds. The radiating head is shaped like a slotted cone, a design that helps improve signal radiation efficiency and directivity. Furthermore, a metallic sub-reflector is embedded on the top surface of the radiating head. The sub-reflector's primary function is to reflect electromagnetic energy from the circular waveguide back onto the antenna's main surface, thereby improving signal transmission efficiency.

[0053] In some embodiments, the sub-reflecting surface of the feed source is extended from bottom to top at a certain angle, matching the top surface structure of the radiation head, so that the sub-reflecting surface can effectively reflect electromagnetic energy to the main surface of the antenna, reducing signal loss and interference; grooves are provided on the edge of the sub-reflecting surface and the radiation head, and the grooves are filled with glue to tightly connect the sub-reflecting surface and the radiation head. This connection method not only improves the stability of the structure, but also reduces the reflection and loss of the signal at the connection.

[0054] In some embodiments, the top surface curve of the radiation head of the feed source is composed of several line segments. This conical extension structure can effectively reduce the edge illumination of the feed source and avoid the leakage wave phenomenon of the energy reflected by the feed source to the main surface. At the same time, this structure allows the feed source to transmit energy at a certain off-focus distance, which can effectively reduce the energy reflected to the main surface from the secondary reflection surface to the feed source, avoiding the coupling reaction that affects the feed source performance.

[0055] In some embodiments, the circular waveguide is a metal structure and can be formed by an extrusion process. Vertically polarized and horizontally polarized signals can be transmitted in the waveguide. It is a waveguide device commonly used in microwave reflector antennas. The modes transmitted in the circular waveguide are TE11, TM01, and TE21 modes. The frequency responses of each mode are different. The transmission bandwidth can be expanded by reasonably configuring the phase of each mode. The present invention optimizes and configures the slot structure and step size of the radiation head, especially the step structure in the waveguide, so as to match the phase of each mode and increase the working bandwidth.

[0056] In some embodiments, the present invention can make full use of the characteristic that the TM mode contributes only to the E-plane pattern and does not contribute to the H-plane pattern, so that the lobe widths of the E-plane and H-plane patterns are basically the same, thereby achieving the purpose of equalizing the two polarization beams of the primary pattern of the feed source; in addition, the circular waveguide uses an inner diameter of 2a=31mm, and the cutoff frequency of each mode is as shown in the following table (1): Table (1)

[0057] According to the above cutoff frequency, the operating frequency fwork must meet the condition: fTE11≤fwork≤fTM11. Therefore, the feed source limit operating frequency of the present invention is 5.6GHz-11.7GHz. The present invention is combined with a dual-band three-polarization feeding network, and the overall system operating frequency is 5.925GHz-11.7GHz, so that the antenna can operate stably in multiple frequency bands, meeting the requirements of modern communication systems for high capacity and high reliability.

[0058] In some embodiments, the adjacent frequency band triple-band dual-polarization antenna of the present invention can be used in conjunction with a parabolic reflector, and can be equipped with reflectors of different diameters according to usage requirements.

[0059] In summary, the present invention proposes a low standing wave and high isolation three-band dual-polarization antenna. By using an ultra-wideband orthogonal mode coupler (5.925 GHz-11.7 GHz), the two polarizations of medium and low frequencies are separated and the high-frequency signal is separated. The high-frequency signal is separated by the high-frequency orthogonal mode coupler. Each polarization port of the medium and low frequencies is loaded with a duplexer to separate the two frequency bands, thereby achieving the purpose of three-band dual polarization. In combination with an ultra-wideband microwave antenna, the TE11, TM01, and TE21 modes can be excited in the waveguide and applied to the entire operating frequency band, achieving the widest operating frequency. The material and shape of the ultra-wideband radiating head effectively distribute the electromagnetic energy rationally and reduce the edge illumination level, so that the antenna can obtain high gain, low sidelobes, high XPD, and low standing wave antenna radiation performance.

Claims

1. A triple-band dual-polarization antenna in adjacent frequency bands, characterized in that: include: An ultra-wideband orthogonal mode coupler includes a first circular waveguide, a mode separation cavity, and a second circular waveguide connected in sequence. The mode separation cavity is connected to a first horizontal polarization branch, a second horizontal polarization branch, a first vertical polarization branch, and a second vertical polarization branch through multiple side coupling holes. The input end of the first circular waveguide is a signal common port, and the output end of the second circular waveguide is a signal main port. A high-frequency orthogonal mode coupler comprising a third circular waveguide, a waveguide transition structure, and a high-frequency vertical polarization port connected in sequence, wherein the waveguide transition structure is connected to the high-frequency horizontal polarization port via a side coupling hole, and the input end of the third circular waveguide is connected to the signal main port; A first duplexer includes a first combining structure, a first low-frequency branch, and a first intermediate frequency branch, wherein output ends of the first horizontally polarized branch and the second horizontally polarized branch are connected to the first combining structure, the first combining structure is connected to the first low-frequency branch and the first intermediate frequency branch, the output end of the first low-frequency branch is a low-frequency horizontally polarized port, and the output end of the second low-frequency branch is an intermediate frequency horizontally polarized port; The second duplexer includes a second combining structure, a second low-frequency branch, and a second intermediate frequency branch, wherein the output ends of the first vertically polarized branch and the second vertically polarized branch are connected to the second combining structure, the second combining structure is connected to the second low-frequency branch and the second intermediate frequency branch, the output end of the second low-frequency branch is a low-frequency vertically polarized port, and the output end of the second intermediate frequency branch is an intermediate frequency vertically polarized port.

2. The adjacent frequency band triple-band dual-polarization antenna according to claim 1, characterized in that: The mode separation cavity is connected to the first horizontal polarization branch through a first side coupling hole, connected to the first vertical polarization branch through a second side coupling hole, connected to the second horizontal polarization branch through a third side coupling hole, and connected to the second vertical polarization branch through a fourth side coupling hole; The first side coupling hole and the third side coupling hole are relatively arranged on the left and right sides of the mode separation cavity, and the second side coupling hole and the fourth side coupling hole are relatively arranged on the upper and lower sides of the mode separation cavity, and the angle between adjacent polarization branches is 90 degrees.

3. The adjacent frequency band triple-band dual-polarization antenna according to claim 1, characterized in that: The diameter of the second circular waveguide is smaller than that of the first circular waveguide, and the mode separation cavity includes a multi-section annular stepped structure with gradually decreasing diameters from the first circular waveguide to the second circular waveguide.

4. The adjacent frequency band triple-band dual-polarization antenna according to claim 1, characterized in that: Each polarization branch includes a multi-gradient ridge waveguide, one end of which is connected to the corresponding side coupling hole, and the other end is provided with multiple gradient spines to form a low-pass filter.

5. The adjacent frequency band triple-band dual-polarization antenna according to claim 1, characterized in that: The high-frequency orthogonal mode coupler includes a vertical rectangular waveguide and a horizontal rectangular waveguide, the vertical rectangular waveguide is connected to the waveguide transition structure, the output end of the vertical rectangular waveguide is the high-frequency vertical polarization port, the waveguide transition structure is connected to the horizontal rectangular waveguide through a side coupling hole, the output end of the horizontal rectangular waveguide is the high-frequency horizontal polarization port, and the waveguide transition structure includes a multi-section stepped structure that gradually narrows along the direction from the third circular waveguide to the vertical rectangular waveguide.

6. The adjacent frequency band triple-band dual-polarization antenna according to claim 1, characterized in that: The side coupling hole is a strip-shaped through hole arranged along the signal direction of the mode separation cavity, and the length of the strip-shaped through hole is one quarter of the wavelength of the 7 GHz low-frequency signal.

7. The adjacent frequency band triple-band dual-polarization antenna according to claim 1, characterized in that: The first combining structure and the second combining structure both include an H-plane 90-degree bend waveguide structure, a three-section twist waveguide structure and a combiner connected in sequence. The combiner is a common port at the input end of the duplexer, which is used to combine the two signals and transmit them to the corresponding low-frequency branch and intermediate-frequency branch.

8. The adjacent frequency band triple-band dual-polarization antenna according to claim 7, characterized in that: An arch structure is formed between the low-frequency branch and the intermediate-frequency branch in the first duplexer and the second duplexer, and the arch structure is connected to the combiner. The low-frequency branch and the intermediate-frequency branch are both provided with multiple resonators, and the resonators are cylindrical or square-shaped.

9. The adjacent frequency band triple-band dual-polarization antenna according to claim 8, characterized in that: In the low-frequency branch, there is a CT cross-coupling structure formed by three adjacent resonators connected by metal rods, and an adjusting screw is provided at the center of the resonator.

10. The adjacent frequency band triple-band dual-polarization antenna according to claim 1, characterized in that: It also includes a feed source, which is connected to the signal common port. The feed source includes a radiation head, a sub-reflector and a circular waveguide. The bottom end of the radiation head is provided with a conical groove, and the sub-reflector is nested in the conical groove. The top end of the radiation head is inserted into one end of the circular waveguide, and the other end of the circular waveguide is connected to the common port of the mode separation cavity through two interconnected cylindrical cavities.

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