TWM656237U - Antenna structure - Google Patents

Abstract

(無)

Description

Antenna structure

The present application relates to an antenna structure, and more particularly to an antenna structure that can be reduced in size and has a reduced manufacturing cost.

The antenna of automotive radar usually uses circuit board technologies such as microstrip antenna and substrate integrated waveguide antenna (SIW antenna), and uses millimeter waves from 76 GHz to 81 GHz for high-resolution object detection. It is known that the material of the antenna needs to be a circuit board material with a low dielectric constant and low dissipation factor, and its size and hole position must be precisely controlled to meet the requirements of low signal loss and high bandwidth.

In recent years, automotive radars have gradually combined waveguide structures with circuit boards, and used air as a medium to reduce the dielectric constant and loss factor. The aforementioned waveguide circuit board can be achieved in two ways: one is to form a waveguide antenna inside the circuit board, and the other is to use plastic injection molding to manufacture a complex-shaped three-dimensional waveguide, and then cover the interior of the three-dimensional waveguide with a metal layer.

However, the size of the waveguide is negatively correlated with the dielectric constant, so the size of the cavity waveguide using air with a low dielectric constant as the medium is difficult to reduce. Furthermore, the waveguide structure manufactured by plastic injection molding must undergo multiple processing, resulting in increased manufacturing costs, and in order to avoid a decrease in electrical properties, the waveguide structure also has higher requirements for assembly alignment and the overall radar structure.

In addition, after the aforementioned waveguide circuit board is assembled, the antenna feed may fail to connect to the circuit board, causing some electromagnetic waves to overflow and causing signal loss and electromagnetic interference. Furthermore, the waveguide structure manufactured by plastic injection molding is usually produced by a foundry and then transferred to an assembly plant for assembly, so it is easy to cause errors with other circuit designs.

The purpose of this application is to provide an antenna structure with reduced size and reduced assembly error.

An embodiment of the present application provides an antenna structure, which includes a circuit board and a housing. The circuit board has a first surface and a second surface opposite to the first surface. The housing is disposed on the first surface of the circuit board, and the housing includes an antenna slot and a through hole. The antenna slot is recessed on a side of the housing adjacent to the circuit board. The through hole extends from a side of the housing away from the circuit board and is connected to the antenna slot. The first surface and the second surface of the circuit board and the housing are all covered by a metal layer.

Accordingly, the antenna structure of the present application can be assembled into a waveguide antenna and a feed structure with reduced size by using a single housing and a three-dimensional structure of a circuit board, and reduce the complexity of subsequent applications. Furthermore, the present application can effectively reduce the material and manufacturing costs of the antenna structure by using a single housing and a low-priced circuit board.

In some implementations, the circuit board may have a first groove, and the first groove may be recessed in the first surface and aligned with the antenna groove.

In some implementations, a width of the first groove may be greater than a width of the antenna groove.

In some implementations, the housing may further include a waveguide groove recessed at the side of the housing adjacent to the circuit board.

In some implementations, the housing may further include a protrusion protruding from the side of the housing adjacent to the circuit board toward the circuit board, and the protrusion may be located in the waveguide groove.

In some implementations, a length of the protrusion may be greater than a depth of the antenna groove and a depth of the waveguide groove.

In some implementations, the circuit board may have a second groove, and the second groove may be recessed in the first surface and aligned with the waveguide groove.

In some implementations, the circuit board may include a bump protruding from the first surface of the circuit board toward the housing, and the bump may be located in the second groove.

In some implementations, the antenna structure may further include a bonding layer disposed and connected between the circuit board and the housing.

In some embodiments, the antenna structure may further include a packaging layer disposed on the first surface of the circuit board, and the packaging layer may surround the housing and cover the side of the housing, but does not cover the side of the housing away from the circuit board.

The following application content provides many different embodiments or examples for realizing different features of the provided subject matter. Specific examples of the like of elements, values, operations, materials, configurations, etc. are described below to simplify the present application. Of course, the examples are merely examples and are not intended to be limiting. Other elements, values, operations, materials, configurations, etc., etc., are also to be considered. For example, in the following description, forming a first feature above a second feature may include an embodiment in which the first feature and the second feature are formed in direct contact, and may also include an embodiment in which an additional feature may be formed between the first feature and the second feature so that the first feature and the second feature are not in direct contact. In addition, the present application may repeatedly refer to numbers and/or text in various examples. This repetition itself does not indicate the relationship between the various embodiments and/or configurations discussed.

In the following text, in order to clearly present the technical features of the present application, the dimensions (e.g., length, width, thickness, and depth) of the elements (e.g., layers, films, substrates, and regions, etc.) in the drawings will be enlarged in unequal proportions, and the number of some elements will be reduced. Therefore, the description and explanation of the embodiments below are not limited to the number of elements in the drawings and the dimensions and shapes presented by the elements, but should cover the dimensions, shapes, and deviations therefrom caused by actual manufacturing steps and/or tolerances. For example, the flat surface shown in the drawings may have rough and/or nonlinear features, and the sharp corners shown in the drawings may be rounded. Therefore, the elements presented in the drawings of the present application are mainly for illustration, and are not intended to accurately depict the actual shape of the elements, nor are they intended to limit the scope of the patent application of the present application.

Please refer to FIG. 1 , which is a cross-sectional view of an antenna structure 100 according to an embodiment of the present application. In some embodiments of the present application, the antenna structure 100 includes a circuit board 110 and a housing 120 .

Specifically, the circuit board 110 has a first surface 111 and a second surface 112 opposite to the first surface 111. The housing 120 is disposed on the first surface 111 of the circuit board 110, and the housing 120 includes an antenna slot 121 and a through hole 122. The antenna slot 121 is recessed on a side of the housing 120 adjacent to the circuit board 110. The through hole 122 extends from a side of the housing 120 away from the circuit board 110 and is connected to the antenna slot 121. The first surface 111 and the second surface 112 of the circuit board 110 and the housing 120 are all covered by a metal layer M to obtain a good electromagnetic wave transmission effect.

The antenna structure 100 may further include a bonding layer 130 disposed and connected between the circuit board 110 and the housing 120. The bonding layer 130 may be made of metal and may be connected to the metal layer M of the circuit board 110 and the housing 120 by pressing, direct copper-copper bonding, sintering, welding or riveting to reduce the problem of electromagnetic wave leakage.

The housing 120 may further include a waveguide groove 123, which is recessed at the side of the housing 120 adjacent to the circuit board 110. The housing 120 may further include a protrusion 124, which protrudes from the side of the housing 120 adjacent to the circuit board 110 toward the circuit board 110, and the protrusion 124 may be located in the waveguide groove 123. In this way, a ridge waveguide may be formed to reduce the size of the antenna structure 100 and widen the bandwidth, thereby increasing the application level of the antenna structure 100, and may be applicable to the circuit design when the contact distance of a radio frequency integrated circuit (RFIC) is reduced.

Please refer to FIG. 2, which is a cross-sectional schematic diagram of an antenna structure 200 according to another embodiment of the present application. The antenna structure 200 of the present embodiment is similar to the aforementioned antenna structure 100, except that the circuit board 210 may have a first groove 213, and the first groove 213 may be recessed in the first surface 211 and located opposite to the antenna groove 221, that is, the circuit board 210 may form the first groove 213 by machining, and the first groove 213 may cooperate with the antenna groove 221 of the housing 220 to form a waveguide structure.

In addition, a length L of the protrusion 224 may be greater than a depth D1 of the antenna groove 221 and a depth D2 of the waveguide groove 223, and the circuit board 210 may have a second groove 214, which may be recessed in the first surface 211 and located opposite to the waveguide groove 223. Thus, the thickness of the housing 220 may be compressed, and the protrusion 224 may be partially accommodated in the second groove 214 of the circuit board 210, so that the structure and properties of the ridge waveguide may be maintained while the size of the housing 220 is reduced.

Please refer to FIG. 3, which is a cross-sectional schematic diagram of an antenna structure 300 of another embodiment of the present application. The antenna structure 300 of the present embodiment is similar to the aforementioned antenna structure 100, except that the circuit board 310 has a second groove 314 and may include a bump 315, which protrudes from the first surface 311 of the circuit board 310 toward the housing 320, and the bump 315 may be located in the second groove 314. In this way, the circuit board 310 and the housing 320 may form a double ridge waveguide together to reduce the size of the antenna structure 300 and widen the bandwidth, thereby increasing the application level of the antenna structure 300, and can be applied to the circuit design when the contact distance of the radio frequency integrated circuit is reduced.

Please refer to FIG. 4, which is a cross-sectional schematic diagram of an antenna structure 400 of another embodiment of the present application. In the antenna structure 400 of the present embodiment, a width W1 of the first groove 413 may be greater than a width W2 of the antenna groove 421, and the antenna structure 400 may further include a copper connection layer 440 disposed and connected between the circuit board 410 and the housing 420 to obtain different waveguide characteristics.

Please refer to FIG. 5, which is a cross-sectional schematic diagram of an antenna structure 500 according to another embodiment of the present application. The antenna structure 500 may further include a packaging layer 550 disposed on the first surface 511 of the circuit board 510, and the packaging layer 550 may surround the housing 520 and cover the side of the housing 520, but does not cover the side of the housing 520 away from the circuit board 510. In this way, the housing 520 and the circuit board 510 can be tightly connected and well aligned, which is helpful for connecting and assembling the antenna structure 500 with other components.

In summary, the antenna structure of the present application is a three-dimensional structure with a single housing and a circuit board, which can be assembled into a reduced-size waveguide antenna and a feed structure, and reduce the complexity of subsequent applications. Furthermore, the present application can effectively reduce the material and manufacturing costs of the antenna structure by using a single housing and a low-priced circuit board.

In addition, in practical applications, multiple antenna structures of the present application can be combined to obtain a high gain effect, and the antenna structure of the present application can be applied to a slot antenna, a horn antenna or other cavity antennas, or used as a microstrip antenna to achieve low-loss transmission purposes.

Although the present application has been disclosed as above by way of embodiments, it is not intended to limit the present application. Anyone skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application. Therefore, the protection scope of the present application shall be subject to the scope defined by the attached patent application.

100,200,300,400,500: Antenna structure 110,210,310,410,510: Circuit board 111,211,311,511: First surface 112: Second surface 120,220,320,420,520: Housing 121,221,421: Antenna slot 122: Perforation 123,223: Waveguide slot 124,224: Protrusion 130: Bonding layer 213,413: First groove 214,314: Second groove 315: Bump 440: Copper connection layer 550: Packaging layer M: Metal layer L: Length D1,D2: Depth W1,W2: Width

Figure 1 is a cross-sectional schematic diagram of an antenna structure of an embodiment of the present application; Figure 2 is a cross-sectional schematic diagram of an antenna structure of another embodiment of the present application; Figure 3 is a cross-sectional schematic diagram of an antenna structure of yet another embodiment of the present application; Figure 4 is a cross-sectional schematic diagram of an antenna structure of yet another embodiment of the present application; and Figure 5 is a cross-sectional schematic diagram of an antenna structure of yet another embodiment of the present application.

100: Antenna structure

110: Circuit board

111: First surface

112: Second surface

120: Shell

121: Antenna slot

122:Piercing

123: Waveguide slot

124: convex part

130:Joint layer

M: Metal layer

Claims (10)

An antenna structure includes: a circuit board having a first surface and a second surface opposite to the first surface; and a housing disposed on the first surface of the circuit board, and the housing includes: an antenna slot recessed on a side of the housing adjacent to the circuit board; and a through hole extending from a side of the housing away from the circuit board and connected to the antenna slot; wherein the first surface and the second surface of the circuit board and the housing are all covered by a metal layer. The antenna structure as described in claim 1, wherein the circuit board has a first groove, the first groove is recessed in the first surface and is opposite to the antenna groove. An antenna structure as described in claim 2, wherein a width of the first groove is greater than a width of the antenna groove. The antenna structure as described in claim 1, wherein the housing further includes a waveguide groove recessed on the side of the housing adjacent to the circuit board. In the antenna structure as described in claim 4, the housing further includes a protrusion protruding from the side of the housing adjacent to the circuit board toward the circuit board, and the protrusion is located in the waveguide groove. An antenna structure as described in claim 5, wherein a length of the protrusion is greater than a depth of the antenna groove and a depth of the waveguide groove. The antenna structure as described in claim 5, wherein the circuit board has a second groove, the second groove is recessed in the first surface and corresponds to the waveguide groove. The antenna structure as described in claim 7, wherein the circuit board includes a protrusion protruding from the first surface of the circuit board toward the housing, and the protrusion is located in the second groove. The antenna structure as described in claim 1 further includes a bonding layer disposed and connected between the circuit board and the housing. The antenna structure as described in claim 1 further includes a packaging layer disposed on the first surface of the circuit board, and the packaging layer surrounds the housing and covers the side of the housing, but does not cover the side of the housing away from the circuit board.

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