Waveguide circular polarizer
By designing a waveguide circular polarizer and combining the input feed structure and polarization transmission structure, the problem of integrating circularly polarized antennas into compact radars was solved, thus improving the radar's detection capability in rainy and snowy weather.
Patent Information
- Application Number
- CN202521552552.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-24
- Publication Date
- 2026-05-15
- Estimated Expiration
- 2035-07-24
AI Technical Summary
Existing circularly polarized antennas are difficult to design, have complex structures, are not easy to integrate into compact radar structures, and rain and snow reduce radar detection capabilities.
Design a waveguide circular polarizer, including an input feed structure, an input linear polarization component transmission structure, an orthogonal linear polarization transmission structure, and a square waveguide structure. The combination of these structures achieves circular polarization of electromagnetic waves. The structure is simple, the size is small, and it can be integrated into a compact radar.
It achieves efficient circular polarization in a compact radar, improving the radar's detection capability in rainy and snowy weather and reducing false alarms and missed alarms.
Smart Images
Figure CN224248953U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of waveguide antenna technology, and in particular to a waveguide circular polarizer. Background Technology
[0002] Waveguide antennas are widely used in radar detection due to their low loss, high channel isolation, compact structure, ease of fabrication, and convenient separation.
[0003] Rain and snow significantly attenuate electromagnetic wave propagation. This attenuation is mainly caused by two factors: 1. Transmission and scattering path losses introduced by rain and snow penetration; 2. Depolarization caused by rain and snow scattering. Rain and snow reduce radar detection capabilities and increase false alarms and missed alarms. Therefore, enhancing radar's adaptability to rain and snow is an important focus in radar design.
[0004] Currently, the main methods to address antenna attenuation caused by rain and snow are increasing antenna gain and converting antennas to circular polarization. However, increasing antenna gain inevitably leads to a reduction in beamwidth, which affects the radar's field of view or radar angle measurement architecture. Circular polarization antennas are more difficult to design and are larger in size, making them less suitable for integration into compact radar structures. Utility Model Content
[0005] The main objective of this invention is to propose a waveguide circular polarizer, which aims to improve the problems of existing circularly polarized antennas being difficult to design, having complex structures, and being difficult to integrate into compact radar structures.
[0006] To achieve the above objectives, the waveguide circular polarizer proposed in this utility model includes:
[0007] An input feeder structure with a rectangular cross-section is used to guide electromagnetic waves; and...
[0008] An output circular polarizer includes an input linear polarization component transmission structure, an orthogonal linear polarization transmission structure, and a square waveguide structure. The input linear polarization component transmission structure is located on one side of the input feed structure in a first direction and is connected to the input feed structure. The orthogonal linear polarization transmission structure is located at a distance from the input linear polarization component transmission structure in a second direction and is connected to the input linear polarization component transmission structure. The square waveguide structure is located on the side of the input linear polarization component transmission structure and the orthogonal linear polarization structure away from the input feed structure in the first direction and is connected to the input linear polarization component transmission structure and the orthogonal linear polarization structure. The end of the square waveguide structure facing away from the input linear polarization component transmission structure and the orthogonal linear polarization structure in the first direction is used to connect a circular polarization signal line.
[0009] In one embodiment, the input feed structure has a dimension A1 in the second direction and a dimension B1 in the third direction; the input line polarization component transmission structure has a dimension A2 in the second direction and a dimension B2 in the third direction; the wavelength is λ0; A1:B1 = A2:B2; and B2 > 0.5λ0; or,
[0010] The input line polarization component transmission structure has a dimension of A2 in the second direction and a dimension of B2 in the third direction, with a wavelength of λ0, where B2 > 2A2 and B2 > 0.5λ0.
[0011] In one embodiment, the input line polarization component transmission structure has a dimension of C2 in the first direction and a waveguide wavelength of λg, where 0.2λg≤C2≤0.25λg.
[0012] In one embodiment, the input line polarization component transmission structure has a dimension of A2 in the second direction and a dimension of B2 in the third direction, and the orthogonal line polarization transmission structure has a dimension of A3 in the second direction, where A3 > B2 - A2.
[0013] In one embodiment, the dimension of the input line polarization component transmission structure in the third direction is B2, and the dimension of the orthogonal line polarization transmission structure in the third direction is B3, where 0.5B2 < B3 < B2.
[0014] In one embodiment, the orthogonal linearly polarized transmission structure has a dimension of C3 in the first direction and a waveguide wavelength of λg, where 0.2λg≤C3≤0.25λg.
[0015] In one embodiment, the dimension of the input line polarization component transmission structure in the first direction is C2, and the dimension of the orthogonal line polarization transmission structure in the first direction is C3, where C2 = C3.
[0016] In one embodiment, the square waveguide structure has a dimension of A4 in the second direction, a dimension of B4 in the third direction, and a wavelength of λ0, where A4 = B4 > 0.5λ0.
[0017] In one embodiment, the square waveguide structure has a dimension of C4 in the first direction and a waveguide wavelength of λg, where C4 > 0.5λg.
[0018] In one embodiment, the input feeder structure is made of at least one of copper, aluminum, and their alloys; and / or,
[0019] The input line polarization component transmission structure is made of at least one of copper, aluminum, and their alloys; and / or,
[0020] The orthogonal linear polarization transport structure is made of at least one of copper, aluminum, and their alloys; and / or,
[0021] The material of the square waveguide structure includes at least one of copper, aluminum, and their alloys.
[0022] In the technical solution of this utility model, the input feed structure inputs electromagnetic waves. At this time, the input linear polarization component transmission structure transmits the same polarization component in the electromagnetic wave as the input feed structure. The orthogonal linear polarization transmission structure forms a polarization component in the electromagnetic wave that is orthogonal to the input direction of the input feed structure. Thus, the input linear polarization component transmission structure and the orthogonal linear polarization transmission structure form two orthogonally distributed polarization components in the circularly polarized signal space. Then, the electromagnetic wave is transmitted to the square waveguide structure. The square waveguide structure acts as a transition between the input linear polarization component transmission structure and the orthogonal linear polarization transmission structure and the circularly polarized signal line or free space, ultimately achieving circular polarization of the electromagnetic wave. With this configuration, the waveguide circular polarizer has a simple structure, small size, and can be integrated into a compact radar. Attached Figure Description
[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.
[0024] Figure 1 A schematic diagram of a waveguide circular polarizer embodiment provided by this utility model;
[0025] Figure 2 for Figure 1 A schematic diagram of the structure of a mid-waveguide circular polarizer (left-handed circular polarization);
[0026] Figure 3 for Figure 2 Schematic diagram of the phase difference between the two polarization components of a mid-waveguide circular polarizer;
[0027] Figure 4 for Figure 2 Schematic diagram of the amplitude ratio of the two polarization components in a medium waveguide circular polarizer;
[0028] Figure 5 for Figure 1 A schematic diagram of the structure of a mid-waveguide circular polarizer (left-handed circular polarization);
[0029] Figure 6 for Figure 5Schematic diagram of the standing wave ratio of a medium waveguide circular polarizer;
[0030] Figure 7 for Figure 5 A schematic diagram of the axial ratio of a medium waveguide circular polarizer.
[0031] Explanation of icon numbers:
[0032] 100. Waveguide circular polarizer; 1. Input feeder structure; 2. Output circular polarizer; 21. Input linear polarization component transmission structure; 22. Orthogonal linear polarization transmission structure; 23. Square waveguide structure.
[0033] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation
[0034] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0035] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.
[0036] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.
[0037] This invention proposes a waveguide circular polarizer, aiming to improve the problems of existing circularly polarized antennas, which are difficult to design, have complex structures, and are not easy to integrate into compact radar structures.
[0038] Please see Figure 1 , Figure 2 as well as Figure 5 In one embodiment of this utility model, the waveguide circular polarizer 100 includes an input feed structure 1 and an output circular polarizer 2. The input feed structure 1 has a rectangular cross-section and is used to guide electromagnetic waves. The output circular polarizer 2 includes an input linear polarization component transmission structure 21, an orthogonal linear polarization transmission structure 22, and a square waveguide junction. The input linear polarization component transmission structure 21 is disposed on one side of the input feed structure 1 in a first direction and is connected to the input feed structure 1. The orthogonal linear polarization transmission structure 22 is spaced apart from the input feed structure 1 in a second direction. An input line polarization component transmission structure 21 is provided and connected to the input line polarization component transmission structure 21. A square waveguide structure 23 is provided on the side of the input line polarization component transmission structure 21 and the orthogonal line polarization transmission structure 22 away from the input feed line structure 1 in a first direction, and is connected to the input line polarization component transmission structure 21 and the orthogonal line polarization structure 22. The end of the square waveguide structure 23 facing away from the input line polarization component transmission structure 21 and the orthogonal line polarization structure 22 in the first direction is used to connect a circularly polarized signal line.
[0039] In the technical solution of this utility model, the input feed structure 1 inputs an electromagnetic wave. At this time, the input linear polarization component transmission structure 21 transmits the same polarization component in the electromagnetic wave as that in the input feed structure 1. The orthogonal linear polarization transmission structure 22 forms a polarization component in the electromagnetic wave that is orthogonal to the input direction of the input feed structure 1. Thus, the input linear polarization component transmission structure 21 and the orthogonal linear polarization transmission structure 22 form two orthogonally distributed polarization components in the circularly polarized signal space. Then, the electromagnetic wave is transmitted to the square waveguide structure 23. The square waveguide structure 23 acts as a transition point between the input linear polarization component transmission structure 21 and the orthogonal linear polarization transmission structure 22 and the circularly polarized signal line or free space, ultimately achieving circular polarization of the electromagnetic wave. With this configuration, the waveguide circular polarizer 100 has a simple structure and small size, and can be integrated into a compact radar.
[0040] First, it is understood that this utility model does not limit the specific shape of the projection of the input linear polarization component transmission structure 21 in the first direction. In one embodiment of this utility model, the dimension of the input linear polarization component transmission structure 21 in the second direction is A2, the dimension in the third direction is B2, the wavelength is λ0, B2 > 2A2, and B2 > 0.5λ0. With this setting, by adjusting the dimensions of the input linear polarization component transmission structure 21 in the second and third directions, the shape of the projection of the input linear polarization component transmission structure 21 in the first direction can be adjusted. When the shape of the projection of the input linear polarization component transmission structure 21 in the first direction is closer to a square, the shape of the input linear polarization component transmission structure 21 is... The impedance is higher. Therefore, in this embodiment, the dimension of the input line polarized component transmission structure 21 in the third direction is set to be more than twice its dimension in the second direction, so as to define the shape of the projection of the input line polarized component transmission structure 21 in the first direction. This makes the shape of the projection of the input line polarized component transmission structure 21 in the first direction approximately the shape of the projection of the input feed structure 1 in the first direction, thereby achieving the purpose of adjusting the impedance of the input line polarized component transmission structure 21. At the same time, the dimension of the input line polarized component transmission structure 21 in the third direction is set to be greater than 0.5λ0, so as to ensure that the size of the input line polarized component transmission structure 21 can meet the cutoff frequency of the metal waveguide, thereby ensuring signal transmission.
[0041] Of course, this utility model does not limit the specific ratio of the dimension of the input line polarization component transmission structure 21 in the second direction to its dimension in the third direction. In some embodiments of this utility model, the ratio of the dimension of the input line polarization component transmission structure 21 in the second direction to its dimension in the third direction can be set to B2:A2 = 2.9; in some other embodiments of this utility model, the ratio of the dimension of the input line polarization component transmission structure 21 in the second direction to its dimension in the third direction can be set to B2:A2 = 2.5; of course, in other embodiments of this utility model, the ratio of the dimension of the input line polarization component transmission structure 21 in the second direction to its dimension in the third direction can also be set to other values, as long as the ratio is within the corresponding range. In actual settings, it can be selected according to the requirements.
[0042] In another embodiment of this utility model, the input feed structure 1 has a dimension of A1 in the second direction and a dimension of B1 in the third direction. The input line polarization component transmission structure 21 has a dimension of A2 in the second direction and a dimension of B2 in the third direction. The wavelength is λ0, A1:B1 = A2:B2, and B2 > 0.5λ0. This configuration sets the shape of the projection of the input line polarization component transmission structure 21 in the first direction to be the same as the shape of the projection of the input feed structure 1 in the first direction, thus achieving impedance adjustment of the input line polarization component transmission structure 21. Furthermore, in this embodiment, the dimension of the input line polarization component transmission structure 21 in the third direction is also set to be greater than 0.5λ0 to ensure that the dimensions of the input line polarization component transmission structure 21 meet the cutoff frequency of the metallic waveguide, thereby ensuring signal transmission.
[0043] It is understood that the dimension of the input linear polarization component transmission structure 21 in the first direction can also affect the circular polarization of the electromagnetic wave by the waveguide circular polarizer 100. In one embodiment of this utility model, the dimension of the input linear polarization component transmission structure 21 in the first direction is C2, the waveguide wavelength is λg, and 0.2λg≤C2≤0.25λg. With this configuration, by adjusting the dimension of the input linear polarization component transmission structure 21 in the first direction, the ratio and phase difference of the two orthogonal polarization components of the electromagnetic wave can be adjusted. Specifically, when the dimension of the input linear polarization component transmission structure 21 in the first direction increases, the ratio of the two orthogonal polarization components of the electromagnetic wave decreases, and the phase difference of the two orthogonal polarization components also decreases; when the dimension of the input linear polarization component transmission structure 21 in the first direction decreases, the ratio of the two orthogonal polarization components of the electromagnetic wave increases, and the phase difference of the two orthogonal polarization components also increases.
[0044] Secondly, this invention does not limit the size of the orthogonal linear polarization transmission structure 22 in the second direction. In one embodiment of this invention, the size of the input linear polarization component transmission structure 21 in the second direction is A2, and the size in the third direction is B2. The size of the orthogonal linear polarization transmission structure 22 in the second direction is A3, where A3 > B2 - A2. With this configuration, by adjusting the size of the orthogonal linear polarization transmission structure 22 in the second direction, the phase difference between the two orthogonal polarization components can be adjusted. When the size of the orthogonal linear polarization transmission structure 22 in the second direction increases, the phase difference between the two orthogonal polarization components decreases; when the size of the orthogonal linear polarization transmission structure 22 in the second direction decreases, the phase difference between the two orthogonal polarization components increases.
[0045] Similarly, this invention does not limit the size of the orthogonal linear polarization transmission structure 22 in the third direction. In a further embodiment of this invention, the size of the input linear polarization component transmission structure 21 in the third direction is B2, and the size of the orthogonal linear polarization transmission structure 22 in the third direction is B3, where 0.5B2 < B3 < B2. It can be understood that by adjusting the size of the orthogonal linear polarization transmission structure 22 in the third direction, the ratio of the two orthogonal polarization components can be adjusted. When the size of the orthogonal linear polarization transmission structure 22 in the third direction increases, the ratio of the two orthogonal polarization components increases; when the size of the orthogonal linear polarization transmission structure 22 in the second direction decreases, the ratio of the two orthogonal polarization components also decreases.
[0046] It should also be noted that this invention does not limit the size of the orthogonal linear polarization transmission structure 22 in the first direction. Adjusting the size of the orthogonal linear polarization transmission structure 22 in the first direction can also affect the circular polarization capability of the waveguide circular polarizer 100 for electromagnetic waves. In a further embodiment of this invention, the size of the orthogonal linear polarization transmission structure 22 in the first direction is C3, the waveguide wavelength is λg, and 0.2λg≤C3≤0.25λg. With this setting, when the size of the orthogonal linear polarization transmission structure 22 in the first direction increases, the proportion of the two orthogonal polarization components of the electromagnetic wave decreases, and the phase difference between the two orthogonal polarization components also decreases; when the size of the orthogonal linear polarization transmission structure 22 in the first direction decreases, the proportion of the two orthogonal polarization components of the electromagnetic wave increases, and the phase difference between the two orthogonal polarization components also increases.
[0047] Furthermore, in this embodiment, the input line polarization component transmission structure 21 and the orthogonal line polarization transmission structure 22 together form an "L"-shaped structure. This structure can form two polarization components that are orthogonal in the circular polarization signal space and a phase difference of 90°. In this embodiment, the dimension of the input line polarization component transmission structure 21 in the first direction is C2, and the dimension of the orthogonal line polarization transmission structure 22 in the first direction is C3, where C2 = C3.
[0048] It should also be noted that this utility model does not limit the specific setting position of the orthogonal linear polarization transmission structure 22. The position of the orthogonal linear polarization transmission structure 22 determines the direction of circular polarization. In this utility model, the waveguide circular polarizer 100 can form left-hand circular polarization and right-hand circular polarization according to the position of the orthogonal linear polarization transmission structure 22.
[0049] Furthermore, this utility model does not limit the shape of the projection of the square waveguide structure 23 in the first direction. In one embodiment of this utility model, the projection of the square waveguide structure 23 in the first direction is rectangular, and the long side and the short side of the rectangle are different. In another embodiment of this utility model, the projection of the square waveguide structure 23 in the first direction is rectangular, and all sides of the rectangle are equal. In other embodiments of this utility model, the projection of the square waveguide structure 23 in the first direction can also be set to other shapes, which can be selected according to the requirements in actual setting.
[0050] Specifically, in this embodiment, the projection of the square waveguide structure 23 in the first direction is a square.
[0051] Therefore, in one embodiment of this utility model, the square waveguide structure 23 has a dimension of A4 in the second direction, a dimension of B4 in the third direction, and a wavelength of λ0, where A4 = B4 > 0.5λ0. With this configuration, by adjusting the dimensions of the square waveguide structure 23 in the second direction and the third direction, the impedance matching between the waveguide circular polarizer 100 and the circularly polarized transmission line or free space can be adjusted. Simultaneously, setting the dimensions of the square waveguide structure 23 in both the second and third directions to be greater than 0.5λ0 also ensures that the dimensions of the square waveguide structure 23 meet the cutoff frequency of the metallic waveguide, thereby guaranteeing signal transmission.
[0052] Of course, this invention does not limit the dimensions of the square waveguide structure 23 in the first direction. In one embodiment of this invention, the dimension of the square waveguide structure 23 in the first direction is C4, and the guided wavelength is λg, where C4 > 0.5λg. Similarly, in this embodiment, by adjusting the dimension of the square waveguide structure 23 in the first direction, the impedance matching between the waveguide circular polarizer 100 and the circularly polarized transmission line or free space can also be adjusted.
[0053] Furthermore, it should be noted that in this utility model, when the end of the square waveguide structure 23 that is away from the input line polarization component transmission structure 21 and the orthogonal line polarization transmission structure 22 in the first direction is not connected to the circular polarization transmission line, the waveguide circular polarizer 100 can be used as an open circular polarization waveguide antenna.
[0054] It should also be noted that this utility model does not limit the specific material of the input feeder structure 1. In this utility model, the material of the input feeder structure 1 includes at least one of copper, aluminum, and their alloys. For example, in one specific embodiment of this utility model, the material of the input feeder structure 1 can be copper; in another embodiment of this utility model, the material of the input feeder structure 1 can be aluminum; and in other embodiments of this utility model, the material of the input feeder structure 1 can also be an alloy.
[0055] Of course, this invention does not limit the specific material of the input line polarization component transmission structure 21. In this invention, the material of the input line polarization component transmission structure 21 includes at least one of copper, aluminum, and their alloys. For example, in one specific embodiment of this invention, the material of the input line polarization component transmission structure 21 can be copper; in another embodiment of this invention, the material of the input line polarization component transmission structure 21 can be aluminum; in other embodiments of this invention, the material of the input line polarization component transmission structure 21 can also be an alloy.
[0056] Similarly, this utility model does not limit the specific material of the orthogonal linear polarization transmission structure 22. The material of the orthogonal linear polarization transmission structure 22 includes at least one of copper, aluminum and their alloys.
[0057] It is understood that this utility model does not limit the specific material of the square waveguide structure 23. In this utility model, the material of the square waveguide structure 23 includes at least one of copper, aluminum and their alloys.
[0058] Please see Figure 2 In a specific embodiment of this utility model, the waveguide circular polarizer 100 is configured as a left-hand circular polarizer, the operating frequency band of the left-hand circular polarizer is 76GHz-79GHz, the dimension of the input feed structure 1 in the second direction is 0.85mm and the dimension in the third direction is 2.5mm, the dimension of the input linear polarization component transmission structure 21 in the second direction is 0.85mm and the dimension in the third direction is 2.5mm, the dimension of the orthogonal linear polarization transmission structure 22 in the first direction is 1.2mm, the dimension in the second direction is 1.8mm and the dimension in the third direction is 1.85mm, and the dimension of the square waveguide structure 23 in the first direction is 4mm and the dimensions in the second and third directions are 2.65mm.
[0059] In this embodiment, Figure 3 The phase difference between the two polarization components of the waveguide circular polarizer 100 in this embodiment; Figure 4This refers to the amplitude ratio of the two polarization components of the waveguide circular polarizer 100 in this embodiment.
[0060] Therefore, in this embodiment, the phase difference of the waveguide circular polarizer 100 does not exceed 90°±10° in the frequency band, and the amplitude ratio does not exceed 3dB in the frequency band, resulting in a good circular polarization effect.
[0061] Please see Figure 5 In another specific embodiment of this utility model, the waveguide circular polarizer 100 is configured as a right-hand circular polarizer and serves as an open circularly polarized waveguide antenna. The operating frequency band of the right-hand circular polarizer is 76GHz-84GHz. The dimension of the input feed structure 1 in the second direction is 0.85mm and the dimension in the third direction is 2.5mm. The dimension of the input linear polarization component transmission structure 21 in the second direction is 0.85mm and the dimension in the third direction is 2.5mm. The dimension of the orthogonal linear polarization transmission structure 22 in the first direction is 1.2mm, the dimension in the second direction is 1.8mm, and the dimension in the third direction is 1.92mm. The dimension of the square waveguide structure 23 in the first direction is 3.5mm, and the dimensions in the second and third directions are 2.65mm.
[0062] In this embodiment, Figure 6 The standing wave ratio (SWR) of the waveguide circular polarizer 100 in this embodiment; Figure 7 This refers to the axial ratio of the waveguide circular polarizer 100 in this embodiment.
[0063] Therefore, in this embodiment, the standing wave ratio of the right-hand circular polarizer is below 1.5, indicating good matching, and the axial ratio is below 3dB across the entire frequency band, resulting in good circular polarization.
[0064] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.
Claims
1. A waveguide circular polarizer, characterized in that, include: An input feeder structure with a rectangular cross-section is used to guide electromagnetic waves. as well as, An output circular polarizer includes an input linear polarization component transmission structure, an orthogonal linear polarization transmission structure, and a square waveguide structure. The input linear polarization component transmission structure is located on one side of the input feed structure in a first direction and is connected to the input feed structure. The orthogonal linear polarization transmission structure is located at a distance from the input linear polarization component transmission structure in a second direction and is connected to the input linear polarization component transmission structure. The square waveguide structure is located on the side of the input linear polarization component transmission structure and the orthogonal linear polarization structure away from the input feed structure in the first direction and is connected to the input linear polarization component transmission structure and the orthogonal linear polarization structure. The end of the square waveguide structure facing away from the input linear polarization component transmission structure and the orthogonal linear polarization structure in the first direction is used to connect a circular polarization signal line.
2. The waveguide circular polarizer as described in claim 1, characterized in that, The input feed structure has a dimension A1 in the second direction and a dimension B1 in the third direction. The input line polarization component transmission structure has a dimension A2 in the second direction and a dimension B2 in the third direction. The wavelength is λ0, A1:B1 = A2:B2, and B2 > 0.5λ0; or, The input line polarization component transmission structure has a dimension of A2 in the second direction and a dimension of B2 in the third direction, with a wavelength of λ0, where B2 > 2A2 and B2 > 0.5λ0.
3. The waveguide circular polarizer as described in claim 1, characterized in that, The input line polarization component transmission structure has a dimension of C2 in the first direction and a waveguide wavelength of λg, where 0.2λg≤C2≤0.25λg.
4. The waveguide circular polarizer as described in claim 1, characterized in that, The input line polarization component transmission structure has a dimension of A2 in the second direction and a dimension of B2 in the third direction. The orthogonal line polarization transmission structure has a dimension of A3 in the second direction, where A3 > B2 - A2.
5. The waveguide circular polarizer as described in claim 1, characterized in that, The dimension of the input line polarization component transmission structure in the third direction is B2, and the dimension of the orthogonal line polarization transmission structure in the third direction is B3, where 0.5B2 < B3 < B2.
6. The waveguide circular polarizer as described in claim 1, characterized in that, The orthogonal linearly polarized transmission structure has a dimension of C3 in the first direction and a waveguide wavelength of λg, where 0.2λg≤C3≤0.25λg.
7. The waveguide circular polarizer as described in claim 1, characterized in that, The dimension of the input line polarization component transmission structure in the first direction is C2, and the dimension of the orthogonal line polarization transmission structure in the first direction is C3, where C2 = C3.
8. The waveguide circular polarizer as described in claim 1, characterized in that, The square waveguide structure has a dimension of A4 in the second direction and a dimension of B4 in the third direction, with a wavelength of λ0, where A4 = B4 > 0.5λ0.
9. The waveguide circular polarizer as described in claim 1, characterized in that, The square waveguide structure has a dimension of C4 in the first direction and a waveguide wavelength of λg, where C4 > 0.5λg.
10. The waveguide circular polarizer as described in claim 1, characterized in that, The input feeder structure is made of at least one of copper, aluminum, and their alloys; and / or, The input line polarization component transmission structure is made of at least one of copper, aluminum, and their alloys; and / or, The orthogonal linear polarization transport structure is made of at least one of copper, aluminum, and their alloys; and / or, The material of the square waveguide structure includes at least one of copper, aluminum, and their alloys.