Ultra-wideband antenna housing with polarization switching capability and antenna assembly

Abstract

The utility model discloses an ultra-wideband antenna housing with polarization switching capability and an antenna assembly, the antenna housing comprises four dielectric layers arranged in parallel at intervals from bottom to top and a support layer clamped between every two adjacent dielectric layers, and each dielectric layer is printed with an n-shaped broken line grid. The n-shaped broken line grids on each dielectric layer are arranged in the same periodicity and have the same deflection direction, and the vertical projection positions are the same. The antenna assembly comprises a linearly polarized antenna and the antenna housing, and the antenna housing is flatly laid at a preset distance above the linearly polarized antenna. And an included angle of 45 degrees is formed between the n-shaped broken line grid and the polarization direction of the linear polarization antenna. By printing n-shaped broken line grids which are periodically arranged and have the same deflection direction on a plurality of dielectric layers clamped with supporting layers, conversion from linearly polarized waves to circularly polarized waves can be realized, and mutual switching from the linearly polarized waves to left-hand / right-hand circular polarization can be realized by overturning the antenna housing by 180 degrees.

Description

Technical Field

[0001] The utility model relates to antenna technology, in particular to an ultra-wideband antenna cover and an antenna component with polarization switching capability. Background Art

[0002] The radome is a structure that protects the antenna system from the external environment. It is required to have good electromagnetic wave transmission characteristics and mechanical properties that can withstand the harsh external environment. Circular polarizers are widely used in radar and satellite communication systems. They can convert linear polarization waves into circular polarization waves. The axial ratio of circular polarization is an important indicator to measure its polarization purity. The smaller the axial ratio, the higher the circular polarization purity of the antenna.

[0003] At present, the commonly used antenna covers with polarization switching capabilities have relatively complex structures and high processing requirements. The polarizer metal layer that is exposed for a long time is easily corroded, which shortens its life. In addition, the corresponding working bandwidth is relatively narrow, which makes it difficult to meet the requirements for polarization transformation under ultra-wideband frequency operation. Utility Model Content

[0004] In order to solve the above-mentioned deficiencies in the related existing technologies, the utility model provides an ultra-wideband antenna cover and antenna assembly with polarization switching capability. By printing a periodically arranged "X"-shaped zigzag grid with the same deflection direction on multiple dielectric layers sandwiched with support layers, the conversion of linear polarization waves to circular polarization waves can be achieved, and by flipping the antenna cover 180°, the mutual switching of linear polarization waves to left-handed / right-handed circular polarization can be achieved.

[0005] In order to achieve the purpose of this utility model, the following technical solutions are proposed:

[0006] An ultra-wideband antenna cover with polarization switching capability includes four dielectric layers arranged in parallel from bottom to top and a support layer sandwiched between each two adjacent dielectric layers, and each dielectric layer is printed with a periodically arranged "X"-shaped zigzag grid. The "X"-shaped zigzag grids on each dielectric layer are arranged in the same period and have the same deflection direction, and have the same vertical projection position.

[0007] Furthermore, from bottom to top, the line widths of the zigzag gratings on the first and fourth dielectric layers are the same, and the line widths of the zigzag gratings on the second and third dielectric layers are the same. The zigzag gratings on the first and second dielectric layers are located on the top surfaces of the dielectric layers, and the zigzag gratings on the third and fourth dielectric layers are located on the bottom surfaces of the dielectric layers.

[0008] Furthermore, the line width of the zigzag grid on the first dielectric layer is different from the line width of the zigzag grid on the second dielectric layer.

[0009] Furthermore, the antenna cover as a whole presents an axisymmetric stacking structure along the central axis in the length direction.

[0010] An antenna assembly includes a linear polarization antenna and an ultra-wideband antenna cover with polarization switching capability, wherein the antenna cover is laid flat at a predetermined distance above the linear polarization antenna. The X-shaped folded line grid forms an angle of 45 degrees with the polarization direction of the linear polarization antenna.

[0011] Furthermore, the radome is used to convert linear polarized waves into circular polarized waves. When the radome is flipped 180 degrees along the central axis in the length direction, the left-handed and right-handed circular polarized waves are switched.

[0012] Compared with the prior art, the above technical solution has the following advantages:

[0013] 1. The radome adopts a laminated structure, and each layer has a small thickness. The overall low profile has the characteristics of ultra-wideband, low insertion loss, and high polarization conversion rate;

[0014] 2. The radome is an axisymmetric structure from bottom to top and can be placed above the linear polarization antenna. By flipping the radome, the conversion of different polarization states can be achieved to meet the usage requirements of different scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the antenna cover of an embodiment of the present application.

[0016] Figure 2 It is a schematic structural diagram of a unit on the antenna cover of an embodiment of the present application.

[0017] Figure 3 It is a schematic diagram of the vertical projection of the X-shaped fold line grid of an embodiment of the present application.

[0018] Figure 4 It is the axial ratio radiation pattern of the linear polarization antenna of the embodiment of the present application.

[0019] Figure 5 4 is a relationship diagram between the axial ratio and frequency of the linear polarization antenna according to an embodiment of the present application. DETAILED DESCRIPTION

[0020] The technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0021] In one aspect of an embodiment of the present application, an ultra-wideband antenna cover having polarization switching capability is provided, such as Figure 1-Figure 3 As shown, it comprises four dielectric layers 1 arranged in parallel and spaced apart from bottom to top and a support layer 3 sandwiched between every two adjacent dielectric layers 1, and each dielectric layer 1 is printed with a "X"-shaped fold line grid 2.

[0022] Specifically, the dielectric layer 1 may be a dielectric substrate with a low dielectric constant and a low loss tangent, which can improve the transmittance of electromagnetic waves and effectively reduce the insertion loss of the entire antenna cover. The support layer 3 is a wave-transmitting material with a foam structure or a honeycomb structure.

[0023] The "X"-shaped zigzag grids 2 on each dielectric layer 1 are arranged in the same period and have the same deflection direction and the same vertical projection position. The antenna cover as a whole is an axisymmetric stacked structure along the central axis in the length direction.

[0024] like Figure 2 As shown, from bottom to top, the line width dimensions of the "X" shaped fold line grating 2 on the first dielectric layer 1 and the fourth dielectric layer 1 are the same, which are defined as the first "X" shaped fold line grating 21; the line width dimensions of the "X" shaped fold line grating 2 on the second dielectric layer 1 and the third dielectric layer 1 are the same, which are defined as the second "X" shaped fold line grating 22.

[0025] The first X-shaped fold line grid 21 on the first dielectric layer 1 is located on the top surface of the first dielectric layer 1, and the second X-shaped fold line grid 22 on the second dielectric layer 1 is located on the top surface of the second dielectric layer 1. Symmetrically, the second X-shaped fold line grid 22 on the third dielectric layer 1 is located on the bottom surface of the third dielectric layer 1, and the first X-shaped fold line grid 21 on the fourth dielectric layer 1 is located on the bottom surface of the fourth dielectric layer 1, thereby forming a top-to-bottom symmetrical stacked structure.

[0026] All the first "X"-shaped folded line grids 21 and the second "X"-shaped folded line grids 22 on the four-layer dielectric layer 1 together constitute a circular polarizer, the principle of which is to decompose the incident linear polarization wave into two directions perpendicular to each other, and generate a certain phase difference when the electromagnetic waves decomposed into two directions perpendicular to each other pass through the "X"-shaped folded line grid 2 to meet the phase condition for the formation of a circular polarization wave; the "X"-shaped folded line grid 2 is at an angle of 45° to the polarization direction of the incident electromagnetic wave, so that the components of the incident linear polarization wave decomposed into two directions perpendicular to each other are basically the same, so as to meet the amplitude condition for forming a circular polarization wave, so that the linear polarization wave components passing through the circular polarizer are finally synthesized to obtain a circular polarization wave.

[0027] The line width of the first “X”-shaped fold line grid 21 is different from the line width of the second “X”-shaped fold line grid 22. Figure 3 As shown, the linear dimension of the second "X"-shaped fold line grid 22 is greater than the linear dimension of the first "X"-shaped fold line grid 21. It can be seen that the vertical projection of the first "X"-shaped fold line grid 21 falls within the coverage of the vertical projection of the second "X"-shaped fold line grid 22. The first "X"-shaped fold line grid 21 and the second "X"-shaped fold line grid 22 adopt different sizes. After optimized design, they work together to convert the linear polarization wave whose polarization direction is at an angle of 45° with the "X"-shaped fold line grid 2 into a circular polarization wave, so as to obtain an ultra-wideband working bandwidth, low insertion loss and high polarization conversion rate.

[0028] Specifically, the line width w of the first and second "X"-shaped folded line grids of the utility model is 0.16mm~0.35mm, the period t of the "X"-shaped arrangement is 2mm~3.5mm, the horizontal plane period p of the folded line grid is 5mm~7mm, and the vertical plane period is 2.5mm~4mm.

[0029] On the other hand, an embodiment of the present application provides an antenna assembly, including a linearly polarized antenna and an ultra-wideband antenna cover with polarization switching capability as described in the previous embodiment. The antenna cover is laid flat at a predetermined distance above the linearly polarized antenna. The "X"-shaped fold line grid 2 forms an angle of 45° with the polarization direction of the linearly polarized antenna. The linearly polarized antenna is fixed, and the predetermined distance is adjusted to obtain the best matching state, thereby reducing the overall return loss. The specific antenna cover is arranged to rotate along the central axis of its own length direction, and a power mechanism can be configured to drive its rotation according to actual conditions. The linearly polarized wave passing through the antenna cover will be converted into a circularly polarized wave. The linearly polarized antenna is fixed. When the antenna cover is flipped 180° along the central axis of the length direction, the left-handed and right-handed circularly polarized waves are switched to meet the use requirements of different scenarios.

[0030] In this example, the axial ratio pattern of the linearly polarized antenna is as follows: Figure 4 As shown in , it can achieve good circular polarization performance; it is generally believed that when the axial ratio is less than 3dB, the electromagnetic wave has good circular polarization performance. The curve of the axial ratio of the linear polarization antenna changing with frequency is shown in Figure 5 As shown, it can be seen that the antenna cover can meet good circular polarization conversion performance at a relative bandwidth of 72% and has ultra-wideband working capability.

[0031] In the embodiment of the present application, an integrated design in which the polarizer is integrated inside the antenna cover can be adopted, which can meet the high transmittance, low insertion loss, and ultra-wideband working requirements, and has a simple structure, light weight, and is easy to process and manufacture.

[0032] The above is only a preferred embodiment of the utility model, and does not mean that it is the only one or limit the utility model. Those skilled in the art should understand that various changes or equivalent replacements made to the utility model without departing from the scope of the utility model are within the scope of protection of the utility model.

Claims

1. An ultra-wideband radome with polarization switching capability, characterized in that: It comprises four dielectric layers (1) arranged in parallel and spaced apart from bottom to top, and a support layer (3) sandwiched between every two adjacent dielectric layers (1), and each dielectric layer (1) is printed with a periodically arranged "X"-shaped folded line grid (2).

2. The ultra-wideband radome with polarization switching capability according to claim 1, characterized in that: The cross-shaped fold line grids (2) on each dielectric layer (1) are arranged in the same periodic pattern and have the same deflection direction, and have the same projection position in the vertical direction.

3. The ultra-wideband radome with polarization switching capability according to claim 2, characterized in that: From bottom to top, the line widths of the 'X'-shaped folded line grids (2) on the first dielectric layer (1) and the fourth dielectric layer (1) are the same, and the line widths of the 'X'-shaped folded line grids (2) on the second dielectric layer (1) and the third dielectric layer (1) are the same.

4. The ultra-wideband radome with polarization switching capability according to claim 3, characterized in that: The "X"-shaped folded line grids (2) on the first dielectric layer (1) and the second dielectric layer (1) are located on the top surface of the dielectric layer (1), and the "X"-shaped folded line grids (2) on the third dielectric layer (1) and the fourth dielectric layer (1) are located on the bottom surface of the dielectric layer (1).

5. The ultra-wideband radome with polarization switching capability according to claim 3, characterized in that: The line width of the zigzag grating (2) on the dielectric layer (1) of the first layer is different from the line width of the zigzag grating (2) on the dielectric layer (1) of the second layer.

6. The ultra-wideband radome with polarization switching capability according to claim 1, characterized in that: The support layer (3) is made of a wave-transmitting material having a foam structure or a honeycomb structure.

7. The ultra-wideband radome with polarization switching capability according to claim 1, characterized in that: The antenna cover as a whole presents an axisymmetric stacking structure along the central axis in the length direction.

8. An antenna assembly, characterized in that: It comprises a linearly polarized antenna and an ultra-wideband radome with polarization switching capability as claimed in any one of claims 1 to 7, wherein the radome is laid flat at a predetermined distance above the linearly polarized antenna.

9. The antenna assembly according to claim 8, characterized in that: The "X"-shaped folded line grid (2) forms an angle of 45° with the polarization direction of the linear polarization antenna.

10. The antenna assembly according to claim 8, characterized in that: The radome is used to convert linear polarized waves into circular polarized waves. When the radome is flipped 180 degrees along the central axis in the length direction, the left-hand rotation and right-hand rotation of the circular polarized waves are switched.

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