Dual-polarized antenna isolation feed structure and high-isolation dual-polarized horn antenna

Abstract

The invention relates to a dual-polarized antenna isolation feed structure and a high-isolation dual-polarized horn antenna, and belongs to the technical field of microwaves. The dual-polarized antenna isolation feed structure comprises a waveguide seat, a first feed waveguide, a second feed waveguide, a first feed socket with a first socket inner core and a second feed socket with a second socket inner core, the first feed waveguide is a square waveguide, and the second feed waveguide is a rectangular waveguide; the first feed waveguide and the second feed waveguide are arranged in the waveguide seat; the first feed socket is connected to a first position of the waveguide seat; the second feed socket is connected to a second position of the waveguide seat; the distance between projection points of the first position and the second position on the axis in the length direction of the waveguide base is L1, and L1 = (1 / 3-2 / 3) * lambda 1; lambda 1 is the nominal center frequency wavelength of the antenna. According to the dual-polarized antenna isolation feed structure provided by the embodiment of the invention, the isolation degree of the port can be improved on the premise that the increase of manufacturing difficulty and cost is not limited.

Description

Technical Field

[0001] The present application relates to the field of microwave technology, and in particular to a dual-polarization antenna isolation feeding structure and a high-isolation dual-polarization horn antenna. Background Art

[0002] In the microwave field, reconnaissance and jamming equipment must process signals of unknown frequency and polarization, requiring antennas with wideband characteristics and the ability to transmit and receive multi-polarized signals. Dual-polarized horn antennas have become a key component in this field due to their reciprocity (combining transmit and receive functions) and their ability to synthesize circularly polarized signals through two ports. These antennas contain two RF ports, one for horizontal and one for vertical polarization. However, insufficient port isolation has long been a technical bottleneck for these antennas. Firstly, crosstalk between the two ports (insufficient isolation) can lead to polarization signal misidentification, seriously compromising system reliability. Secondly, in traditional designs, due to the physical proximity of the two ports and the lack of effective isolation mechanisms, port isolation is typically limited to 20dB (basic threshold) or 25dB (optimal performance). Furthermore, increasing isolation to above 30dB requires high manufacturing precision (such as micron-level assembly tolerances) and complex debugging processes, resulting in significant production costs and difficulties in ensuring consistent mass production.

[0003] Therefore, how to break through the bottleneck of high isolation above 30dB without significantly increasing manufacturing complexity and cost has become a core issue that needs to be urgently addressed in dual-polarization antenna design. Summary of the Invention

[0004] The purpose of this application is to address the above problems and provide a dual-polarization antenna isolation feeding structure, which can improve the isolation of the ports without increasing the manufacturing difficulty and cost, thereby improving the above problems.

[0005] This application is achieved through the following technical solutions: In a first aspect, the present application provides a dual-polarization antenna isolated feeding structure, the dual-polarization antenna isolated feeding structure including a waveguide base, a first feeding waveguide, a second feeding waveguide, a first feeding socket having a first socket inner core, and a second feeding socket having a second socket inner core, the first feeding waveguide is a square waveguide, and the second feeding waveguide is a rectangular waveguide; wherein the first feeding waveguide and the second feeding waveguide are arranged in the waveguide base; wherein the first feeding socket is connected to the first position of the waveguide base; wherein the second feeding socket is connected to the second position of the waveguide base; wherein the first socket inner core is connected to the first feeding waveguide; wherein the second socket inner core is connected to the second feeding waveguide; the distance between the projection points of the first position and the second position on the longitudinal axis of the waveguide base is L1, and satisfies, L1=(1 / 3~2 / 3)×λ1; wherein λ1 is the nominal center frequency wavelength of the antenna.

[0006] In the technical solution of the embodiments of the present application, the first feed waveguide is a square waveguide, and the second feed waveguide is a rectangular waveguide. Rectangular waveguides are typically used for single-polarization transmission because their structure easily supports the dominant TE10 mode. The electric field is distributed along the wider side, resulting in a fixed polarization direction. If rectangular waveguides are used for both polarizations, two would need to be placed side by side, but this would result in coupling issues and potentially excessive size. However, due to their symmetry, square waveguides can support two orthogonal TE10 modes, equivalent to stacking two rectangular waveguides. This improves isolation between the two polarization ports and results in a more compact structure. During operation, an external signal enters through the top horn antenna and propagates along the main propagation direction. Horizontally polarized signals (with the electric field direction parallel to the width of the waveguide base) are primarily coupled to the first feed waveguide, while vertically polarized signals (with the electric field direction parallel to the height of the waveguide base) are primarily coupled to the second feed waveguide below. The horizontally polarized signal propagates along the length of the first feed waveguide in the TE10 mode, reaching the first feed socket at the rear end. The signal is converted into an electrical signal by the core of the first socket and output to the receiver. The vertically polarized signal propagates along the length of the second feed waveguide in TE10 mode, reaching the second feed receptacle at the front, where it is converted into an electrical signal within the second receptacle's core for output. Crosstalk from the first feed waveguide, after leaking into the second feed waveguide, propagates from the rear to the front of the waveguide base (corresponding to L1). Because L1 = (1 / 3 to 2 / 3) × λ1, this creates a phase shift and destructively interferes with the second feed waveguide's native signal (propagating in the forward direction), canceling out the crosstalk energy. At the antenna's nominal center frequency, the isolation between the first and second feed receptacles is high (exceeding 30dB). This isolation is maintained over a wide bandwidth, significantly improving over conventional designs and meeting high isolation requirements. The layout of the first and second feed waveguides can be formed in one go using conventional CNC machining, eliminating the need for specialized precision machining. Installation of the first and second feed receptacles requires only conventional fastening methods, eliminating complex commissioning steps, significantly simplifying manufacturing and assembly. Because high machining precision is not required, the manufacturing cost of a single structure is lower than that of traditional high-precision solutions; the simplified assembly process improves production efficiency and is suitable for mass production.

[0007] In some embodiments, the method further includes a third feeding socket having a third socket inner core; the third socket inner core is connected to a third position of the first feeding waveguide.

[0008] In the technical solution of the embodiments of this application, after a horizontally polarized signal enters the first feed waveguide, a portion is transmitted along the waveguide to the first feed socket at a first position, where it is converted into an electrical signal by the first socket's internal core and output. The remaining portion continues along the waveguide to the third feed socket at a third position, where it is converted into an electrical signal by the third socket's internal core and output. The addition of the third feed socket enables the first feed waveguide to simultaneously output two horizontally polarized related signals, enabling multi-port acquisition of horizontally polarized signals and providing the hardware foundation for subsequent signal diversity reception, phase comparison, and other processing.

[0009] In some embodiments, the first position is located at the front end of the third position in the main propagation direction of the electromagnetic wave.

[0010] In the technical solution of the embodiments of this application, after a horizontally polarized signal enters the waveguide base, it propagates along the main propagation direction of the electromagnetic wave, first coupling to the front end of the first feed waveguide (at the first position). It then continues along the back end of the first feed waveguide, reaching the third position. The first position at the front end is closer to the signal input end, where the received horizontally polarized signal has minimal attenuation, and thus serves as the primary signal channel. The signal at the third position at the back end serves as a secondary channel, and the combination of the two improves signal acquisition reliability.

[0011] In some embodiments, the distance between the projection points of the first position and the third position on the longitudinal axis of the waveguide base is L2.

[0012] In the technical solution of the embodiment of the present application, the distance between the projection points of the first position and the third position on the longitudinal axis of the waveguide base is L2, so that there are quantifiable differences in the amplitude and phase of the two signals. These differences can be used as signal features in the multi-channel fusion algorithm to improve the signal recognition capability in complex environments.

[0013] In some embodiments, |L1-L2| is (λ2-λ1) / 2; wherein λ2 is the wavelength corresponding to the lower edge frequency of the antenna band; and wherein |L1-L2| is the absolute value of the difference between L1 and L2.

[0014] In the technical solution of the embodiment of the present application, when the signal frequency drops from the center frequency to the lower edge frequency, the wavelength will change accordingly, resulting in a change in the phase propagation characteristics. The design of |L1-L2|=(λ2-λ1) / 2 can compensate for the phase shift caused by this wavelength change through the difference between L1 and L2, so that the crosstalk suppression effect at different frequencies remains consistent. At the lower edge frequency of the band, L1 is still within the range of 1 / 3 to 2 / 3λ1, ensuring the phase cancellation effect of the crosstalk signal; at the same time, the difference between L2 and L1 adapts to the wavelength change, so that the isolation between the third feed socket and the second feed socket remains stable within the wide bandwidth.

[0015] In some embodiments, a feeding path selection module is further included, and the feeding path selection module is used to switch the first feeding socket or the third feeding socket as the current feeding path according to the operating frequency.

[0016] In the technical solution of the embodiment of the present application, when the operating frequency is in an interval close to the center frequency, the first feed socket is selected; when the operating frequency is in an interval close to the lower edge of the frequency band, the third feed socket is selected. The connection between the selected feed socket and the back-end link is turned on, and the path of the other feed socket is cut off at the same time, so that the signal at the current operating frequency is transmitted only through the selected feed socket. By switching the path according to the operating frequency, the first feed socket and the third feed socket can respectively exert the optimal signal transmission performance in their adapted frequency interval and the third feed socket in their adapted frequency interval, the signal transmission loss in the entire frequency band is reduced compared to a single path, and the isolation stability is further improved. In addition, there is no need to manually adjust the hardware or recalibrate during the process of adjusting the feed path. The feed path selection module can automatically complete the path switching as the operating frequency changes, adapt to the fast frequency hopping scenario, solve the problem that the traditional structure requires manual intervention when the frequency changes, and is more convenient to use.

[0017] In some embodiments, a transition region between the first feeding waveguide and the second feeding waveguide in the waveguide seat is a stepped impedance matching structure.

[0018] In the technical solution of the embodiment of the present application, the transition area between the first feeding waveguide and the second feeding waveguide in the waveguide seat is a stepped impedance matching structure, and the cross-sectional size of each step gradually changes along the signal propagation direction, gradually transitioning from the square waveguide cross-section of the first feeding waveguide to the rectangular waveguide cross-section adapted to the second feeding waveguide, or vice versa, and the height and width changes of the steps follow the impedance continuity principle. The steps in the transition area are distributed in the overlapping section where the two waveguides intersect, the step difference of the steps is uniform, and the height and width changes of each step are the same, ensuring a smooth impedance transition. When the horizontally polarized signal propagates in the first feeding waveguide to the transition area, the stepped structure causes the waveguide cross-sectional size to change gradually, avoiding impedance mismatching caused by cross-sectional mutations and reducing signal reflections. When the vertically polarized signal is transmitted through the transition area in the second feeding waveguide, impedance matching is also achieved through the stepped structure, so that more energy is transmitted along the target waveguide, reducing energy loss caused by reflection.

[0019] In some embodiments, a diaphragm is further included, which is mounted on the inner wall of the waveguide seat through a hinge shaft; the diaphragm is arranged adjacent to the inner core of the first socket; the angle between the plane where the diaphragm is located and the inner wall of the waveguide seat is a, and satisfies 15°≤a≤75°.

[0020] In the technical solution of the embodiment of the present application, when a horizontally polarized signal propagates in the first feed waveguide to the position of the diaphragm, the diaphragm produces directional reflection or refraction of the signal through the angle a formed with the inner wall of the waveguide, reducing the diffusion of the signal in non-target directions (such as the direction of the second feed waveguide) and enhancing the energy convergence toward the inner core of the first socket. The diaphragm's convergence effect on the target signal increases the signal strength received by the inner core of the first socket and reduces the loss caused by energy diffusion. For crosstalk signals that may leak from the first feed waveguide to the second feed waveguide, the diaphragm can change its propagation path by adjusting the angle, causing part of the crosstalk signal to attenuate due to path extension or direction deviation, forming a double suppression with the phase cancellation mechanism of L1. The directional guiding effect of the diaphragm reduces cross-polarization crosstalk and further improves isolation.

[0021] In some embodiments, it also includes a movable rod, the outer circumference of which is provided with a thread; the side wall of the waveguide seat is provided with an adjustment hole that cooperates with the thread of the movable rod; one end of the movable rod is movably connected to the diaphragm through a slide groove structure; rotating the movable rod can drive the diaphragm to rotate around the hinge axis to continuously adjust the angle a.

[0022] In the technical solution of the embodiments of the present application, when the diaphragm angle a needs to be adjusted, the exposed end of the movable rod is rotated. Because the movable rod and the adjustment hole are threaded together, the movable rod advances and retreats along the axis during rotation. The extended end of the movable rod slides within the diaphragm's slide slot. As the movable rod advances and retreats, the slider exerts a thrust or pull on the slide slot, driving the diaphragm to rotate about the hinge axis, causing the angle a between the diaphragm and the inner wall of the waveguide seat to continuously change. The angle a can also be adjusted according to the operating frequency, for example: at high frequencies, it can be adjusted to 15°-30° to reduce signal reflections; at low frequencies, it can be adjusted to 60°-75° to enhance signal convergence, ensuring that the diaphragm can function optimally at different frequencies. The threaded drive of the movable rod and the slide slot enable continuous adjustment of the angle a, which is more precise than manually fixing the angle, can adapt to a more detailed frequency range, and further minimize fluctuations in cross-polarization isolation across the entire frequency band. The diaphragm angle can be adjusted by rotating the movable rod without disassembling the waveguide seat, and the adjustment effect can be observed in real time. This solves the problem of traditional manual adjustment requiring repeated disassembly and trial and error, and improves operational convenience.

[0023] In a second aspect, the present application provides a high-isolation dual-polarization horn antenna, comprising the above-mentioned dual-polarization antenna isolation feeding structure and a conical horn structure fixedly connected to the radiating end of the waveguide base.

[0024] In the technical solution of the embodiment of the present application, after the signal enters the conical horn structure, the cross-section of the horn gradually expands from the waveguide size to the radiation port size, achieving smooth impedance matching and reducing signal reflection. At the same time, the conical structure forms a directional constraint on the two polarization signals. The horizontal polarization signal is concentratedly radiated along the horizontal direction of the horn, and the vertical polarization signal is concentratedly radiated along the vertical direction. The cone angle design of the conical horn makes the radiation beam have a specific directionality, reduces the energy diffusion in the non-target direction, and reduces the interference of environmental reflections on different polarization channels; at the same time, the focusing effect of the horn improves the signal gain and enhances the ability to transmit and receive long-distance signals. The symmetrical structure of the conical horn works synergistically with the isolation mechanism of the above-mentioned dual-polarization antenna isolation feeding structure, that is, the conical horn structure reduces external interference from entering different polarization channels, and the feeding structure suppresses internal crosstalk. The two together ensure that the overall cross-polarization isolation of the antenna is high.

[0025] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 An exploded diagram of a dual-polarization antenna isolation feed structure provided in some embodiments of the present application; Figure 2 A schematic diagram of the external structure of a high-isolation dual-polarization horn antenna provided in some embodiments of the present application; Figure 3 A top view of a high-isolation dual-polarization horn antenna provided in some embodiments of the present application; Figure 4 for Figure 3 Cross-sectional view at AA in the middle; Figure 5 A schematic diagram of the internal structure of a dual-polarized antenna isolation feed structure provided in some embodiments of the present application; Figure 6 A waveform diagram of antenna port isolation of a dual-polarized antenna isolation feed structure provided in some embodiments of the present application; Figure 7 This is the waveform diagram of the traditional antenna port isolation.

[0028] Icons: 1-waveguide seat; 11-first feeding waveguide; 12-second feeding waveguide; 13-first position; 14-second position; 15-third position; 16-adjustment hole; 2-first feeding socket; 20-first socket core; 3-second feeding socket; 30-second socket core; 4-third feeding socket; 40-third socket core; 5-diaphragm; 50-slide groove; 6-movable rod; 7-conical speaker structure. DETAILED DESCRIPTION

[0029] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0030] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0031] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0032] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0033] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0034] The term "multiple" used in this application refers to more than two (including two). Similarly, "multiple groups" refers to more than two (including two) groups, and "multiple sheets" refers to more than two (including two) sheets.

[0035] According to some embodiments of the present application, optionally, Figure 1~Figure 2 、 Figure 4~Figure 5 As shown, the present application provides a dual-polarization antenna isolated feeding structure, which includes a waveguide base 1, a first feeding waveguide 11, a second feeding waveguide 12, a first feeding socket 2 having a first socket core 20, and a second feeding socket 3 having a second socket core, the first feeding waveguide 11 is a square waveguide, and the second feeding waveguide 12 is a rectangular waveguide, wherein the first feeding waveguide 11 and the second feeding waveguide 12 are arranged in the waveguide base 1; wherein the first feeding socket 2 is connected to the first position 13 of the waveguide base 1; wherein the second feeding socket 3 is connected to the second position 14 of the waveguide base 1; wherein the first socket core 20 is connected to the first feeding waveguide 11; wherein the second socket core is connected to the second feeding waveguide 12; the distance between the projection points of the first position 13 and the second position 14 on the longitudinal axis of the waveguide base 1 is L1, and satisfies, L1=(1 / 3~2 / 3)×λ1; wherein λ1 is the nominal center frequency wavelength of the antenna.

[0036] Multiple sets of mounting holes with different spacing (corresponding to L1 = 1 / 3λ1, 1 / 2λ1, and 2 / 3λ1, respectively) can be reserved along the longitudinal axis of the waveguide base 1, along the projection path of the first position 13 and the second position 14. Each set of holes is adapted to a different center frequency. By changing the mounting positions of the first and second feed sockets 2 and 3, the universal requirements of multi-band reconnaissance equipment can be met.

[0037] When L1>2 / 3×λ1, the crosstalk signal propagates over a long distance in the waveguide, causing the original signal to attenuate due to waveguide loss, affecting the receiving sensitivity.

[0038] When L1 is less than 1 / 3×λ1, the phase shift is less than 120°, the interference cancellation effect is weakened, and the isolation is reduced.

[0039] The first feed waveguide 11 is a square waveguide, and the second feed waveguide 12 is a rectangular waveguide. Rectangular waveguides are typically used for single-polarization transmission because their structure easily supports the main mode TE10. The electric field is distributed along the wider side, so the polarization direction is fixed. If rectangular waveguides are used for both polarizations, two may need to be placed side by side, but this will cause coupling problems and may be too large. Due to their symmetry, square waveguides can support two orthogonal TE10 modes, which is equivalent to stacking two rectangular waveguides together. This improves the isolation between the two polarization ports and makes the structure more compact. During specific use, the external signal enters from the top horn antenna and propagates along the main propagation direction. The horizontally polarized signal (the electric field direction is parallel to the width direction of the waveguide base 1) is mainly coupled to the first feed waveguide 11, and the vertically polarized signal (the electric field direction is parallel to the height direction of the waveguide base 1) is mainly coupled to the second feed waveguide 12 at the bottom. The horizontally polarized signal propagates along the length of the first feed waveguide 11 in TE10 mode, reaching the first feed receptacle 2 at the rear end. It is converted into an electrical signal by the first receptacle's core 20 and output to the receiver. The vertically polarized signal propagates along the length of the second feed waveguide 12 in TE10 mode, reaching the second feed receptacle 3 at the front end. It is converted into an electrical signal by the second receptacle's core and output. After the crosstalk signal from the first feed waveguide 11 leaks into the second feed waveguide 12, it must propagate from the rear to the front of the waveguide base 1 (corresponding to L1). Because L1 = (1 / 3 to 2 / 3) × λ1, a phase shift occurs, causing destructive interference with the native signal (propagating in the forward direction) of the second feed waveguide 12, canceling out the crosstalk energy. At the antenna's nominal center frequency, the isolation between the first and second feed receptacles 2 and 3 is high (exceeding 30 dB). This isolation is maintained over a wide bandwidth, significantly improving over conventional designs and meeting high isolation requirements. The layout of the first and second feed waveguides 11, 12 can be formed in one go through conventional CNC machining, eliminating the need for specialized precision machining processes. The first and second feed receptacles 2, 3 require only conventional fastening methods, eliminating the need for complex commissioning steps, significantly reducing manufacturing and assembly complexity. Because high machining precision is not required, the manufacturing cost of a single assembly is lower than that of traditional high-precision solutions. The simplified assembly process improves production efficiency, making it suitable for mass production.

[0040] In the specific application process, the isolation degree of the dual-polarized antenna isolation feed structure provided by the present application is measured to obtain the following Figure 6 The waveform shown is similar to the Figure 7 From the comparison with the waveform diagram of the traditional antenna port isolation shown, it can be seen that the dual-polarization antenna isolation feeding structure provided in the present application can effectively and stably improve the isolation.

[0041] According to some embodiments of the present application, optionally, Figure 1~Figure 2 、 Figure 4~Figure 5As shown, the third feeding socket 4 having a third socket inner core 40 is further included; the third socket inner core 40 is connected to the third position 15 of the first feeding waveguide 11 .

[0042] The dual-polarized antenna isolated feeding structure provided in the present application can control the distance between the third position 15 and the first position 13 (such as adjusting it to 1 / 4 or 1 / 2 of the wavelength corresponding to different frequency bands) so that the first feeding socket 2 and the third feeding socket 4 can respectively adapt to horizontally polarized signals of different frequency bands, thereby realizing multi-band signal acquisition of a single feeding waveguide and improving the antenna's processing capability for wide-band signals.

[0043] After the horizontally polarized signal enters the first feeding waveguide 11, a portion travels along the waveguide to the first feeding socket 2 at the first position 13, where it is converted into an electrical signal for output by the first socket core 20. The remaining portion continues along the waveguide to the third feeding socket 4 at the third position 15, where it is converted into an electrical signal for output by the third socket core 40. The addition of the third feeding socket 4 enables the first feeding waveguide 11 to simultaneously output two horizontally polarized signals, enabling multi-port acquisition of horizontally polarized signals and providing the hardware foundation for subsequent signal diversity reception, phase comparison, and other processing.

[0044] According to some embodiments of the present application, optionally, the first position 13 is located at the front end of the third position 15 in the main propagation direction of the electromagnetic wave.

[0045] After entering the waveguide base 1, the horizontally polarized signal propagates along the main propagation direction of the electromagnetic wave, first coupling to the front end of the first feed waveguide 11 (at the first position 13). It then continues to propagate along the back end of the first feed waveguide 11, reaching the third position 15. The first position 13 at the front end is closer to the signal input end, where the received horizontally polarized signal has minimal attenuation, and thus serves as the main signal channel. The signal at the third position 15 at the back end serves as an auxiliary channel, and the combination of the two improves signal acquisition reliability.

[0046] According to some embodiments of the present application, optionally, Figure 4 As shown, the distance between the projection points of the first position 13 and the third position 15 on the longitudinal axis of the waveguide base 1 is L2.

[0047] Multiple groups of third position 15 mounting holes are set along the length direction of the waveguide base 1 (different mounting holes are selected to adjust L2). By changing the installation position of the third feeding socket 4, the time difference can be adjusted to adapt to the timing accuracy requirements of different back-end algorithms.

[0048] The distance between the projection points of the first position 13 and the third position 15 on the longitudinal axis of the waveguide base 1 is L2, so that there are quantifiable differences in the amplitude and phase of the two signals. These differences can be used as signal features in the multi-channel fusion algorithm to improve the signal recognition capability in complex environments.

[0049] According to some embodiments of the present application, optionally, |L1-L2| is (λ2-λ1) / 2; wherein λ2 is the wavelength corresponding to the lower edge frequency of the antenna band; wherein |L1-L2| is the absolute value of the difference between L1 and L2.

[0050] When |L1-L2|>(λ2-λ1) / 2, the difference between L1 and L2 exceeds the compensation requirement, resulting in over-compensation of the phase offset of the crosstalk signal at the lower edge frequency of the band. This weakens the interference cancellation effect, and the isolation between cross-polarization ports cannot be stably maintained at a high value. In addition, the isolation fluctuation in adjacent frequency bands increases, affecting system reliability.

[0051] When |L1-L2| < (λ2-λ1) / 2, the difference is insufficient to compensate for the phase shift caused by wavelength variation, resulting in insufficient phase cancellation of crosstalk signals at the lower edge of the band. The isolation between cross-polarization ports is significantly reduced, and as the frequency approaches the edge, the isolation continues to deteriorate, undermining the stability of the broadband performance.

[0052] When the signal frequency drops from the center frequency to the lower edge frequency, the wavelength changes accordingly, resulting in a change in the phase propagation characteristics. The design of |L1-L2|=(λ2-λ1) / 2 compensates for the phase shift caused by this wavelength change through the difference between L1 and L2, maintaining consistent crosstalk suppression across different frequencies. At the lower edge frequency of the band, L1 remains within the range of 1 / 3 to 2 / 3λ1, ensuring phase cancellation of crosstalk signals. At the same time, the difference between L2 and L1 adapts to wavelength changes, ensuring stable isolation between the third feed socket 4 and the second feed socket 3 across a wide bandwidth.

[0053] According to some embodiments of the present application, optionally, a feeding path selection module is further included, and the feeding path selection module is used to switch the first feeding socket 2 or the third feeding socket 4 as the current feeding path according to the operating frequency.

[0054] The feed path selection module can use high-speed RF switching devices to compress the switching response time to adapt to high-frequency hopping scenarios, ensuring that the optimal path can still be matched in real time when the frequency changes rapidly.

[0055] When the operating frequency is in a range close to the center frequency, the first feed socket 2 is selected; when the operating frequency is in a range close to the lower edge of the frequency band, the third feed socket 4 is selected. The connection between the selected feed socket and the back-end link is turned on, and the path of the other feed socket is cut off at the same time, so that the signal at the current operating frequency is transmitted only through the selected feed socket. By switching the path according to the operating frequency, the first feed socket 2 and the third feed socket 4 can respectively exert the optimal signal transmission performance in their adapted frequency range and the frequency range, and the signal transmission loss in the entire frequency band is reduced compared to a single path, and the isolation stability is further improved. In addition, there is no need to manually adjust the hardware or recalibrate during the adjustment of the feed path. The feed path selection module can automatically complete the path switching as the operating frequency changes, adapt to the fast frequency hopping scenario, solve the problem of the traditional structure requiring manual intervention when the frequency changes, and is more convenient to use.

[0056] According to some embodiments of the present application, optionally, Figure 1 、 Figure 4~Figure 5 As shown, the transition region between the first feeding waveguide 11 and the second feeding waveguide 12 in the waveguide base 1 is a stepped impedance matching structure.

[0057] The stepped structure of the transition region between the first feeding waveguide 11 and the second feeding waveguide 12 can be composed of a plurality of replaceable stepped modules. By adjusting the step heights and widths of different levels, the impedance characteristics of different frequency bands can be adapted to achieve efficient transmission of multi-band signals by a single waveguide base 1.

[0058] The transition region between the first feeding waveguide 11 and the second feeding waveguide 12 in the waveguide seat 1 is a stepped impedance matching structure. The cross-sectional dimensions of each step gradually change along the signal propagation direction, gradually transitioning from the square waveguide cross-section of the first feeding waveguide 11 to the rectangular waveguide cross-section adapted to the second feeding waveguide 12, or vice versa. The height and width changes of the steps follow the impedance continuity principle. The steps in the transition region are distributed in the overlapping section where the two waveguides intersect. The step difference of the steps is uniform, and the height and width changes of each step are the same, ensuring a smooth impedance transition. When the horizontally polarized signal propagates in the first feeding waveguide 11 to the transition region, the stepped structure causes the waveguide cross-sectional dimensions to gradually change, avoiding impedance mismatching caused by cross-sectional mutations and reducing signal reflections. When the vertically polarized signal is transmitted through the transition region in the second feeding waveguide 12, impedance matching is also achieved through the stepped structure, allowing more energy to be transmitted along the target waveguide, reducing energy loss caused by reflection.

[0059] According to some embodiments of the present application, optionally, Figure 4~Figure 5 As shown, it also includes a diaphragm 5, which is mounted on the inner wall of the waveguide base 1 through a hinge axis; the diaphragm 5 is arranged adjacent to the first socket core 20; the angle between the plane where the diaphragm 5 is located and the inner wall of the waveguide base 1 is a, and satisfies, 15°≤a≤75°.

[0060] A composite absorbing material layer (covering only the non-reflective area) may be provided on the surface of the diaphragm 5 so that the diaphragm 5 has both signal guiding and crosstalk absorbing functions, thereby reducing cross-polarization crosstalk.

[0061] When a < 15°, the diaphragm 5 is nearly parallel to the inner wall of the waveguide, and the guiding effect is weak; When a>75°, the diaphragm 5 is close to a vertical state, which may easily cause excessive reflection and result in signal disorder.

[0062] When a horizontally polarized signal propagates through the first feed waveguide 11 to the diaphragm 5, the diaphragm 5, through the angle a formed with the inner wall of the waveguide, produces directionally reflected or refracted signals, reducing signal diffusion in non-target directions (such as the direction of the second feed waveguide 12) and enhancing energy convergence toward the first socket core 20. The diaphragm 5's convergence of the target signal increases the signal strength received by the first socket core 20 and reduces losses due to energy diffusion. For crosstalk signals that may leak from the first feed waveguide 11 to the second feed waveguide 12, the diaphragm 5 can adjust its propagation path by adjusting its angle, causing some crosstalk signals to be attenuated due to path extension or directional deviation, thus achieving dual suppression with the phase cancellation mechanism of L1. The diaphragm 5's directional guidance reduces cross-polarization crosstalk and further improves isolation.

[0063] According to some embodiments of the present application, optionally, Figure 4~Figure 5 As shown, it also includes a movable rod 6, the outer circumference of which is provided with a thread; the side wall of the waveguide base 1 is provided with an adjustment hole 16 that cooperates with the thread of the movable rod 6; one end of the movable rod 6 is movably connected to the diaphragm 5 through a slide groove 50 structure; rotating the movable rod 6 can drive the diaphragm 5 to rotate around the hinge axis to continuously adjust the angle a.

[0064] Angle scales can be marked on the exposed end of the movable rod 6 and the side wall of the waveguide seat 1 so that the angle value can be directly read during adjustment without relying on back-end signal monitoring, thereby improving operating efficiency.

[0065] A damping coating may be added to the threads of the movable rod 6 and the adjustment hole 16 to enhance the self-locking ability of the thread fit. Even in a strong vibration environment, the angle a can remain stable, reducing the frequency of readjustment.

[0066] When the angle a of the diaphragm 5 needs to be adjusted, the exposed end of the movable rod 6 is rotated. Since the movable rod 6 and the adjustment hole 16 are threaded together, the movable rod 6 moves forward and backward along the axis during rotation. The extended end of the movable rod 6 slides in the slide groove 50 of the diaphragm 5. As the movable rod 6 moves forward and backward, the slider generates a thrust or pull on the slide groove 50, driving the diaphragm 5 to rotate around the hinge axis, causing the angle a between the diaphragm 5 and the inner wall of the waveguide seat 1 to continuously change. It can also be adjusted according to the operating frequency. For example, it can be adjusted to 15°~30° at high frequencies to reduce signal reflections; and adjusted to 60°~75° at low frequencies to enhance signal convergence, ensuring that the diaphragm 5 can perform optimally at different frequencies. The threaded transmission of the movable rod 6 cooperates with the slide groove 50 to achieve continuous adjustment of the angle a. Compared with the manual angle fixing method, it is more precise and can adapt to a more detailed frequency range, further reducing the fluctuation of the cross-polarization isolation within the entire frequency band. The angle of the diaphragm 5 can be adjusted by rotating the movable rod 6 without disassembling the waveguide seat 1. The effect can be observed in real time during the adjustment process, which solves the problem of traditional manual adjustment requiring repeated disassembly and trial and error, and improves the convenience of operation.

[0067] According to some embodiments of the present application, optionally, Figures 1 to 5 As shown, the present application provides a high-isolation dual-polarization horn antenna, comprising the above-mentioned dual-polarization antenna isolation feeding structure and a conical horn structure 7 fixedly connected to the radiation end of the waveguide base 1.

[0068] The cone angle of the conical speaker structure 7 can be a gradually changing structure that is slow at the front and steep at the back, which further broadens the bandwidth while ensuring the gain and adapts to signal reception and transmission in a wider frequency range.

[0069] After the signal enters the conical horn structure 7, the cross-section of the horn gradually expands from the waveguide size to the radiation port size, achieving smooth impedance matching and reducing signal reflection. At the same time, the conical structure forms a directional constraint on the two polarization signals. The horizontal polarization signal is concentratedly radiated along the horizontal direction of the horn, and the vertical polarization signal is concentratedly radiated along the vertical direction. The cone angle design of the conical horn gives the radiation beam a specific directionality, reduces energy diffusion in non-target directions, and reduces the interference of environmental reflections on different polarization channels. At the same time, the focusing effect of the horn increases signal gain and enhances the ability to transmit and receive long-distance signals. The symmetrical structure of the conical horn works synergistically with the isolation mechanism of the above-mentioned dual-polarization antenna isolation feeding structure, that is, the conical horn structure 7 reduces external interference from entering different polarization channels, and the feeding structure suppresses internal crosstalk. The two together ensure that the overall cross-polarization isolation of the antenna is high.

[0070] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and components may be substituted with equivalents without departing from the scope of the present application. In particular, the various technical features described in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions within the scope of the claims.

Claims

1. A dual-polarization antenna isolation feed structure, comprising a waveguide base, characterized in that: include: a first feeding waveguide, wherein the first feeding waveguide is a square waveguide; a second feeding waveguide, wherein the second feeding waveguide is a rectangular waveguide; A first power feeding socket having a first socket inner core; A second power feeding socket having a second socket inner core; Wherein, the first feeding waveguide and the second feeding waveguide are arranged in the waveguide seat; Wherein, the first feeding socket is connected to the first position of the waveguide seat; Wherein, the second feeding socket is connected to the second position of the waveguide base; Wherein, the first socket inner core is connected to the first feeding waveguide; Wherein, the second socket inner core is connected to the second feeding waveguide; The distance between the projection points of the first position and the second position on the longitudinal axis of the waveguide base is L1, and satisfies the following condition: L1=(1 / 3~2 / 3)×λ1; Where λ1 is the nominal center frequency wavelength of the antenna.

2. The dual-polarization antenna isolation feed structure according to claim 1, characterized in that: Also includes: a third power feeding socket having a third socket inner core; The third socket inner core is connected to a third position of the first feeding waveguide.

3. The dual-polarization antenna isolation feed structure according to claim 2, characterized in that: The first position is located at the front end of the third position in the main propagation direction of the electromagnetic wave.

4. The dual-polarization antenna isolation feeding structure according to claim 3, characterized in that: The distance between the projection points of the first position and the third position on the longitudinal axis of the waveguide base is L2.

5. The dual-polarization antenna isolation feeding structure according to claim 4, characterized in that: Satisfies, |L1-L2| is (λ2-λ1) / 2; Where λ2 is the wavelength corresponding to the lower edge frequency of the antenna band; Where |L1-L2| is the absolute value of the difference between L1 and L2.

6. The dual-polarization antenna isolation feeding structure according to claim 5, characterized in that: Also includes: The feeding path selection module is configured to switch the first feeding socket or the third feeding socket as a current feeding path according to an operating frequency.

7. The dual-polarization antenna isolation feeding structure according to claim 1, characterized in that: A transition region between the first feeding waveguide and the second feeding waveguide in the waveguide seat is a stepped impedance matching structure.

8. The dual-polarization antenna isolation feeding structure according to claim 1, characterized in that: Also includes: A diaphragm is mounted on the inner wall of the waveguide seat via a hinge shaft; The diaphragm is arranged adjacent to the first socket inner core; The included angle between the plane where the diaphragm is located and the inner wall of the waveguide seat is a, and satisfies 15°≤a≤75°.

9. The dual-polarization antenna isolation feeding structure according to claim 8, characterized in that: Also includes: A movable rod having a threaded outer circumference; The side wall of the waveguide seat is provided with an adjustment hole that cooperates with the thread of the movable rod; One end of the movable rod is movably connected to the diaphragm via a sliding groove structure; Rotating the movable rod can drive the diaphragm to rotate around the hinge axis to continuously adjust the angle a.

10. A high-isolation dual-polarization horn antenna, comprising the dual-polarization antenna isolation feeding structure according to any one of claims 1 to 9, characterized in that: include: A conical horn structure is fixedly connected to the radiation end of the waveguide base.

Images