Radome for adjusting antenna pattern

Abstract

A radome for adjusting an antenna pattern comprises a housing and a plurality of through-holes formed in the housing. The housing has a first surface and a second surface. The through-holes extend from the first surface through the housing to the second surface. The distance between the through-holes and / or the size of the through-holes are designed so that a first antenna pattern generated by the antenna when radiating changes to a second antenna pattern after passing through the radome.

Description

Technical Field

[0001] The present invention relates to the technical field of antenna pattern adjustment, and in particular to a radome for adjusting the antenna pattern. Background Art

[0002] For driving safety, installing radar on the side of a vehicle to detect obstacles is almost indispensable. One of the main architectures for these small and medium-sized radar antennas mounted on the side of a vehicle is a block array antenna, composed of traditional patch antennas arranged in a specific pattern. However, because the detection range of a patch antenna is difficult to adjust, when a block array antenna is installed close to the ground, the wide field of view of the antenna can cause the radar signal to reflect off the ground or vehicle body, resulting in excessive energy received by the signal receiver.

[0003] To address the issue of excessively wide radiation angles, existing technologies often combine multiple block antennas to concentrate the resulting radiation pattern. However, this approach wastes resources by requiring more antennas. Furthermore, more antennas take up more space, making the vehicle-side radar significantly larger and more difficult to design. Summary of the Invention

[0004] In order to solve the above problems, the present invention provides a radome for adjusting the antenna pattern. One of the purposes of this radome is to enable the radiation pattern of the antenna to change after passing through this radome, thereby reducing the number of additional block antennas required to change the antenna radiation pattern, thereby reducing the adverse effects caused by adding additional block antennas.

[0005] From one perspective, the present invention provides a radome for adjusting an antenna pattern. The radome is adapted to cover an antenna so that a first antenna pattern generated by the antenna when radiating changes to a second antenna pattern after passing through the radome. The radome is characterized by comprising a housing and a plurality of through-holes formed in the housing. The housing has a first surface and a second surface. The through-holes extend through the housing from the first surface to the second surface. The distance between the through-holes or the through-hole dimensions are designed so that the first antenna pattern generated by the antenna when radiating changes to the second antenna pattern after passing through the radome.

[0006] In one embodiment, the first surface is virtually divided into a non-porous area and a porous area, and the porous area is further virtually divided into a plurality of through-hole block columns extending along the first direction and arranged along the second direction. The through-holes in the same through-hole block column have the same hole size, and the through-hole size of the through-holes in each through-hole block column is different from the through-hole size of the through-holes in other through-hole block columns.

[0007] In one embodiment, the above-mentioned porous area is divided by the non-porous area into a first porous sub-area and a second porous sub-area respectively located on both sides of the non-porous area and not connected to each other, and the through-hole size of the through-holes included in the through-hole block column in the first porous sub-area gradually decreases along the above-mentioned second direction.

[0008] In one embodiment, the through-hole sizes of the through-holes included in the through-hole block column in the second through-hole sub-region gradually increase along the second direction.

[0009] In one embodiment, the centers of the through holes in each through hole block column are connected to form a straight line.

[0010] In one embodiment, the center of the antenna is projected onto the antenna center projection position on the first surface, and vertical distances between each through hole block column and the antenna center projection position are different.

[0011] As described above, the antenna pattern-adjustable radome provided in the present invention features multiple through-holes of specific sizes and locations. These through-holes can alter the radome's ultimate dielectric constant. Therefore, based on the antenna's original radiation pattern and the desired final radiation pattern, the required dielectric constant at each location within the radome can be calculated. Ultimately, by adjusting the size and location of the through-holes, the dielectric constant at each location within the radome can be adjusted to meet the desired radiation pattern. Therefore, the antenna pattern-adjustable radome provided by the present invention can directly alter the radiation pattern of an existing antenna without requiring an additional antenna, thereby overcoming the shortcomings of the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 FIG. 1 is a schematic diagram of the positions of a radome and an antenna for adjusting an antenna pattern according to an embodiment of the present invention.

[0013] Figure 2A FIG. 1 is a top view of a radome for adjusting antenna pattern according to an embodiment of the present invention.

[0014] Figure 2B for Figure 2A An enlarged view of a portion of the left half of the illustrated embodiment.

[0015] Figure 2C for Figure 2AEnlarged view of a portion of the right half of the embodiment shown

[0016] Figure 3A This is a schematic diagram of the final radiation pattern of the antenna when the radome is not placed.

[0017] Figure 3B To produce Figure 3A Schematic diagram of the final radiation pattern of the radar formed by an antenna with a radiation pattern and a radome according to an embodiment of the present invention.

[0018] The description of the accompanying drawings is as follows:

[0019] 10, 20: Radome

[0020] 15: Antenna

[0021] 100, 200: Shell

[0022] 102, 104: Surface

[0023] 130, 2600, 2602, 2604, 2606, 2620, 2622, 2624, 2626: Through hole

[0024] 210: Non-porous area

[0025] 220: Hole area

[0026] 222, 224: Perforated sub-areas

[0027] 250: Central area

[0028] 2220, 2222, 2224, 2226, 2240, 2242, 2244, 2246: Through hole block column

[0029] 2502: Antenna center projection position

[0030] R1~R5:Distance

[0031] X, Y: direction DETAILED DESCRIPTION

[0032] Please refer to Figure 1, which is a schematic diagram of the positions of the radome and antenna for adjusting the antenna pattern according to one embodiment of the present invention. As shown in the figure, in this embodiment, the radome 10 covers the front surface of the antenna 15. That is, the radome 10 is positioned so that the majority of the electromagnetic waves radiated by the antenna 15 pass through the radome 10. The housing 100 of the radome 10 can be made of a material with a dielectric constant greater than 1, such as PBT (Polybutylene Terephthalate) plastic. Furthermore, a plurality of through-holes 130 are formed in the radome 10, extending through the housing 100. In this embodiment, the through-holes 130 extend from one surface 102 of the housing 100 (hereinafter referred to as the first surface) through the interior of the housing 100 and onto a surface 104 (hereinafter referred to as the second surface) opposite the first surface 102 and facing the antenna 15.

[0033] Based on the principles of electromagnetic waves, different dielectric constants affect the direction of the resulting electric field radiation. Therefore, when focusing the antenna pattern formed by the electromagnetic waves radiated by antenna 15, the area of ​​radome 10 closest to the focal point (hereinafter referred to as the focal area) can be configured to have the highest dielectric constant, while the dielectric constants of other areas of radome 10 decrease as the distance from the focal area increases. Based on this situation, the present invention designs the distance between these through holes or the through hole dimensions so that the antenna pattern originally radiated by antenna 15 (hereinafter referred to as the first antenna pattern) can be changed to the desired antenna pattern (hereinafter referred to as the second antenna pattern) after passing through radome 10.

[0034] Please refer to Figure 2A , which is a top view of a radome with an adjusted antenna pattern according to one embodiment of the present invention. In this embodiment, it is desired to focus the adjusted antenna pattern more closely above the central region 250 of the housing 200 than the original antenna pattern (the antenna center projection position 2502 in the central region 250 is the projection point of the center of the antenna shielded by the housing 200). Therefore, the design principle in this embodiment is to ensure that the central region 250 of the housing 200 has the highest dielectric constant of all positions in the entire radome 20. By designing the through-hole size and position of the through-holes penetrating the housing 200, the dielectric constant of the housing 200 decreases as it approaches the sides of the housing 200.

[0035] As shown in the figure, the surface of the housing 200 is virtually divided into multiple regions, including a non-porous region 210 and a perforated region 220. To ensure that the antenna pattern is focused near the antenna centerline after passing through the radome 20, this embodiment does not form through-holes in the non-porous region 210 surrounding the central region 250. This ensures that the dielectric constant of the non-porous region 210 is the highest in the entire radome 20 (equivalent to the dielectric constant of the material used to manufacture the housing 200).

[0036] Next, in this embodiment, the perforated region 220 is divided by the non-perforated region 210 into a first perforated sub-region 222 and a second perforated sub-region 224, which are located on either side of the non-perforated region 210 and are not connected to each other. The first perforated sub-region 222 includes through-hole block columns 2220, 2222, 2224, and 2226, while the second perforated sub-region 224 includes through-hole block columns 2240, 2242, 2244, and 2246. These through-hole block columns 2220-2226 and 2240-2246 extend along a direction Y (hereinafter also referred to as the first direction). The through-hole block columns 2220-2226 are arranged along a direction X (hereinafter also referred to as the second direction) in the first perforated sub-region 222, while the through-hole block columns 2240-2246 are also arranged along the direction X in the second perforated sub-region 224.

[0037] Since through holes are dug in the shell 200, the average dielectric constant of the through hole block column 2220 will be generated by combining the entity of the shell 200 in the through hole block column 2220 and the air in each through hole 2600, the average dielectric constant of the through hole block column 2222 will be generated by combining the entity of the shell 200 in the through hole block column 2222 and the air in each through hole 2602, the average dielectric constant of the through hole block column 2224 will be generated by combining the entity of the shell 200 in the through hole block column 2224 and the air in each through hole 2604, and the average dielectric constant of the through hole block column 2226 will be generated by combining the entity of the shell 200 in the through hole block column 2226 and the air in each through hole 2606. According to the design principles mentioned previously, in order to achieve a better electromagnetic wave focusing effect, the closer the radome is to the focusing point, the higher the dielectric constant should be. Therefore, in this embodiment, the average dielectric constant of the non-porous area 210 is the highest, the average dielectric constant of the through-hole block column 2226 is lower than the dielectric constant of the non-porous area 210, the average dielectric constant of the through-hole block column 2224 is lower than the average dielectric constant of the through-hole block column 2226, the average dielectric constant of the through-hole block column 2222 is lower than the average dielectric constant of the through-hole block column 2224, and the average dielectric constant of the through-hole block column 2220 is lower than the average dielectric constant of the through-hole block column 2222.

[0038] Specifically, since air is the medium with the smallest dielectric constant except for vacuum, in the design of the present invention, the portion relatively close to the periphery of the antenna cover should have a relatively large amount of air, so as to effectively reduce the average dielectric constant there.

[0039] To achieve the above-mentioned effects, the present embodiment first designs the average dielectric constant that each through-hole block column 2220-2226 must possess. The area occupied by each through-hole block column 2220-2226 is then determined based on the wavelength of the electromagnetic wave and the focal length during focusing. Finally, the proportion of through holes in each through-hole block column 2220-2226 is determined based on the area occupied by each through-hole block column 2220-2226 and the average dielectric constant that each through-hole block column 2220-2226 must possess.

[0040] like Figure 2B As shown, when the vertical distance between the right edge of the through-hole block column 2226 and the center projection position 2502 of the antenna is R1, the vertical distance between the right edge of the through-hole block column 2224 and the center projection position 2502 of the antenna is R2, the vertical distance between the right edge of the through-hole block column 2222 and the center projection position 2502 of the antenna is R3, the vertical distance between the right edge of the through-hole block column 2220 and the center projection position 2502 of the antenna is R4, and the vertical distance between the center projection position 2502 of the antenna and the left edge of the shell 200 is R5, each through-hole block column 2220 to 2226 can be used to plan the volume ratio of the solid part of the shell 200 to the size of the through-hole according to the average dielectric constant to be achieved, or, under the premise that the thickness of the shell 200 is uniform, the volume ratio of the shell 200 in the planning can be used. Figure 2A The area ratio of the solid part on the surface shown and the size of the through hole is used to achieve the target of the planned volume ratio.

[0041] In this embodiment, in order to achieve the effect of left-right balanced changes, as shown in FIG. Figure 2C As shown, the vertical distance between the left edge of the through hole block column 2246 and the center projection position 2502 of the antenna is designed to be R1, the vertical distance between the left edge of the through hole block column 2244 and the center projection position 2502 of the antenna is designed to be R2, the vertical distance between the left edge of the through hole block column 2242 and the center projection position 2502 of the antenna is designed to be R3, the vertical distance between the left edge of the through hole block column 2240 and the center projection position 2502 of the antenna is designed to be R4, and the vertical distance between the center projection position 2502 of the antenna and the right edge of the housing 200 is R5, and the size of each through hole and the distance between each other are also designed to be consistent. Figure 2B That is, the left and right halves of the housing 200 are designed to be symmetrical to each other.

[0042] Since the area closer to the radome's periphery should have a relatively large air volume, the requirement for providing more air space can be achieved by reducing the spacing between the through-holes near the outside while maintaining the same size for all through-holes. Alternatively, the requirement for providing more air space can be achieved by increasing the size of the through-holes near the outside. Because the faster the dielectric constant decreases, the more pronounced the electromagnetic wave focusing effect is, the two aforementioned methods can be used simultaneously to rapidly change the total amount of air that can be accommodated, thereby increasing the rate of decrease in the dielectric constant and the electromagnetic wave focusing effect.

[0043] According to the above, in the first perforated sub-region 222, the size of the through hole 2600 in the through hole block column 2220 is larger than the size of the through hole 2602 in the through hole block column 2222, and the distance between the two through holes 2600 in the through hole block column 2220 is also smaller than the distance between the two through holes 2602 in the through hole block column 2222. Therefore, the average dielectric constant of the through hole block column 2220 and the through hole block column 2222 can produce a more obvious difference, thereby enhancing the focusing effect. Similarly, the size of the through hole 2602 in the through hole block column 2222 is larger than the size of the through hole 2604 in the through hole block column 2224, and the distance between the two through holes 2602 in the through hole block column 2222 is also smaller than the distance between the two through holes 2604 in the through hole block column 2224; the size of the through hole 2604 in the through hole block column 2224 is larger than the size of the through hole 2606 in the through hole block column 2226, and the distance between the two through holes 2604 in the through hole block column 2224 is also smaller than the distance between the two through holes 2606 in the through hole block column 2226.

[0044] In contrast, in the second hole-containing sub-region 224, the size of the through-hole 2620 in the through-hole block column 2240 is larger than the size of the through-hole 2622 in the through-hole block column 2242, and the distance between the two through-holes 2620 in the through-hole block column 2240 is also smaller than the distance between the two through-holes 2622 in the through-hole block column 2242; the size of the through-hole 2622 in the through-hole block column 2242 is larger than the size of the through-hole 2622 in the through-hole block column 2244. 4, and the distance between the two through holes 2622 in the through hole block column 2242 is also smaller than the distance between the two through holes 2624 in the through hole block column 2244; the size of the through hole 2624 in the through hole block column 2244 is larger than the size of the through hole 2626 in the through hole block column 2246, and the distance between the two through holes 2624 in the through hole block column 2244 is also smaller than the distance between the two through holes 2626 in the through hole block column 2246.

[0045] In order to make the effect of the same through-hole block column on the radiation pattern as consistent as possible, in this embodiment, the sizes of all through-holes in the same through-hole block column are designed to be the same size and evenly distributed in this through-hole block column. Taking the through-hole block column 2220 as an example, eleven through-holes 2600 of the same size are evenly formed in the through-hole block column 2220, and the center points of these eleven through-holes 2600 are connected in a straight line. The design method of forming through-holes in a uniform manner or connecting the centers of through-holes in a straight line is also used in other through-hole block columns in this embodiment. However, it is worth mentioning that in situations where a very precise radiation pattern is not required (such as general vehicle-side radar), through-holes can also be formed in a non-uniform manner in a through-hole block column, and the center points of each through-hole in the same through-hole block column do not necessarily need to be connected in a straight line. Similarly, the through holes in the same column of through hole block columns 2222-2226 and through hole block columns 2240-2246 may be manufactured with or without designing the through holes to be the same size, evenly distributed in the through hole block columns, and connected in a straight line at the centers.

[0046] Please refer to the following Figure 3A and Figure 3B ,in, Figure 3A is a schematic diagram of the final radiation pattern of the antenna when the radome is not placed. Figure 3B It is produced Figure 3A Schematic diagram of the final radiation pattern of the radar formed after the antenna with the radiation pattern of is used in conjunction with the radome of an embodiment of the present invention. Figure 3B The radome used looks like Figure 2A 、 Figure 2B and Figure 2C Generally, there are four layers of through-hole blocks of different sizes on the left and right sides of the radome (or shell), and their design values ​​are shown in Table 1 below. It should be noted that the first layer in Table 1 refers to the through-hole blocks on the radome. Figure 2A The area between the antenna center projection position 2502 and the right edge of the through hole block column 2226, the second layer refers to the area on the antenna cover such as Figure 2A The third layer refers to the area of ​​the through hole block column 2226 on the antenna cover. Figure 2A The fourth layer refers to the area of ​​the through hole block column 2224 on the antenna cover. Figure 2A The area of ​​the through hole block column 2222, and the fifth layer refers to the area on the antenna cover such as Figure 2A The area of ​​the through hole block column 2220. In addition, Ri refers to the aforementioned R1 to R5, Si refers to the distance between the centers of the through holes in each layer, and di refers to the radius of the through holes in each layer.

[0047] Table 1

[0048] First floor Second floor Third floor Fourth floor Fifth floor Ri 2.86mm 4.23mm 5.54mm 6.68mm 7.85mm Si 0 1.59mm 1.46mm 1.35mm 1.25mm di 0 0.5mm 0.64mm 0.75mm 0.86mm

[0049] As can be seen from Table 1, in this embodiment, the distance between the through holes (Si) is designed to be smaller as the distance gets closer to the left and right sides of the radome (Ri becomes larger), while the size of the through holes (di) is designed to be larger. As a result, the space ratio occupied by the through holes increases rapidly as the distance gets closer to the left and right sides of the radome, and its impact on the radiation pattern can be seen by comparing Figure 3A and Figure 3B And learned.

[0050] from Figure 3A and Figure 3B It can be clearly seen in the radiation pattern that when the radome is not placed, the maximum actual measured radiation point in the final radiation pattern is -37.3dB at 100 degrees, and its half-power beamwidth (HPBW) is about 66 degrees wide (approximately between 72 degrees and 138 degrees). After placing the radome made according to the above method, the maximum actual measured radiation point in the final radiation pattern is also located at 100 degrees, but the intensity is enhanced to -35.6dB, and the corresponding half-power beamwidth is focused to about 15 degrees wide (approximately between 92.5 degrees and 107.5 degrees). This shows that the radome made using the above method can indeed effectively change the focusing effect of the original antenna.

[0051] In summary, the antenna pattern-adjustable radome described above modifies the radome's ultimate average dielectric constant by forming multiple through-holes of specific sizes and locations within the radome. Therefore, based on the antenna's original radiation pattern and the desired final radiation pattern, the user can calculate the average dielectric constant required at each location within the radome to modify the radiation pattern. The user can then adjust the size and location of the through-holes accordingly to ensure that the average dielectric constant at each location within the radome meets the desired radiation pattern. Therefore, the antenna pattern-adjustable radome provided by the present invention can directly modify the radiation pattern of an existing antenna without the use of additional antennas, thereby overcoming the shortcomings of the prior art.

Claims

1. A radome for adjusting an antenna pattern, adapted to cover an antenna so that a first antenna pattern generated by the antenna when radiating changes to a second antenna pattern after passing through the radome, characterized in that: The radome includes: A housing and a plurality of through holes formed in the housing, the housing having a first surface and a second surface, the through holes extending from the first surface through the housing to the second surface, wherein at least one of a distance between the through holes and a through hole size of the through holes is designed so that the first antenna pattern generated by the antenna when radiating changes to the second antenna pattern after passing through the radome; The first surface is virtually divided into a non-porous area and a porous area, and the porous area is further virtually divided into a plurality of through-hole block columns extending along a first direction and arranged along a second direction, wherein the first direction and the second direction are linear directions respectively. The through-holes in the same through-hole block column have the same through-hole size, and the through-hole size of the through-holes in each through-hole block column is different from the through-hole size of the through-holes in other through-hole block columns.

2. The radome according to claim 1, wherein: The porous area is divided by the non-porous area into a first porous sub-area and a second porous sub-area respectively located on both sides of the non-porous area and not connected to each other, and the through-hole sizes of the through-holes included in the through-hole block column in the first porous sub-area gradually decrease along the second direction.

3. The radome according to claim 2, wherein: The through-hole sizes of the through-holes included in the through-hole block column in the second through-hole sub-region gradually increase along the second direction.

4. The radome according to claim 1, wherein: The centers of the through holes in each through hole block column are connected to form a straight line.

5. The radome according to claim 1, wherein: The center of the antenna is projected onto an antenna center projection position on the first surface, and vertical distances between each of the through hole block columns and the antenna center projection position are different.

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