TW202416583A - Antenna structure and electronic device - Google Patents

Abstract

An antenna structure and an electronic device are provided. The electronic device includes the antenna structure. The antenna structure includes a metal housing, a circuit board, a grounding metal portion, a feeding metal portion, a first shorting metal portion, a second shorting metal portion, and a third shorting metal portion. The metal housing has an opening. The circuit board is disposed in the metal housing, and the circuit board faces the opening. The grounding metal portion and the feeding metal portion are disposed on the circuit board. The feeding metal portion has a grounding end and a feeding end, and the grounding end is connected to the grounding metal portion. The first shorting metal portion is connected between the feeding portion and the metal housing. The feeding metal portion is used for feeding a signal though the signal source to excite the metal housing to generate an operating frequency.

Description

Antenna structure and electronic devices

The present invention relates to an antenna structure and an electronic device, and in particular to an antenna structure suitable for a metal casing and an electronic device having the antenna structure.

Currently, communication products are developing towards miniaturization, and they pursue aesthetic appearance and sufficient mechanical strength. Under this trend, most communication products use metal as their outer shell. However, due to the characteristics of the metal shell, it is easy to affect the antenna inside the product, thereby reducing the communication quality of the mobile device. In addition, since the antenna needs to be set up with clear areas on the upper and lower sides of its installation position, no metal or other circuit components can exist in the clear area. However, in this way, the space utilization rate inside the electronic device will be reduced.

Therefore, how to successfully design an antenna with acceptable performance within the limited space of an electronic device with a metal casing has become one of the important issues that this field wants to solve.

The present invention mainly provides an antenna structure and an electronic device to solve the problem of insufficient antenna design space inside the electronic device.

In order to solve the above-mentioned technical problems, one of the technical solutions adopted by the present invention is to provide an antenna structure and an electronic device. The electronic device includes an antenna structure. The antenna structure includes a metal shell, a circuit board, a grounded metal part, a feed metal part, a first short-circuit metal part, a second short-circuit metal part and a third short-circuit metal part. The metal shell has an opening. The circuit board is arranged in the metal shell, and the circuit board is opposite to the opening. The grounded metal part is arranged on the circuit board. The feed metal part is arranged on the circuit board, and the feed metal part has a grounding end and a feeding end, the grounding end is connected to the grounded metal part, and the feed end is connected to a signal source. The first short-circuit metal part has a first end and a second end, the first end is connected to the feed metal part, and the second end is connected to the metal shell. One end of each of the second short-circuit metal part and the third short-circuit metal part is connected to the ground metal part, and the other end is connected to the metal shell. The feeding metal part is used to feed a signal through a signal source to excite the metal shell to generate an operating frequency.

One of the beneficial effects of the present invention is that the antenna structure and the electronic device provided by the present invention can generate the required operating frequency by arranging a circuit board inside a metal casing with a unidirectional opening, and arranging a feed metal part, a first short-circuit metal part, a second short-circuit metal part and a third short-circuit metal part on the circuit board to excite the metal casing. Compared with the antenna structure of the prior art, the antenna structure provided by the present invention uses the metal casing as the radiator of the antenna, so the directivity is lower and can be applied to a variety of different usage scenarios of the electronic device.

To further understand the features and technical contents of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are only used for reference and description and are not used to limit the present invention.

The following is a specific embodiment to illustrate the implementation of the "antenna element and electronic device" disclosed in the present invention. The technical personnel in this field can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments. The details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. In addition, the drawings of the present invention are only for simple schematic illustrations and are not depicted according to actual sizes. Please note in advance. The following implementation will further explain the relevant technical content of the present invention in detail, but the disclosed content is not used to limit the scope of protection of the present invention. In addition, it should be understood that, although the terms "first", "second", "third", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are mainly used to distinguish one element from another element. In addition, the term "or" used herein may include any one or more combinations of the associated listed items depending on the actual situation. In addition, the term "or" used herein may include any one or more combinations of the associated listed items depending on the actual situation.

Referring to FIGS. 1 to 4 , FIG. 1 is a schematic diagram of an electronic device of the present invention, FIG. 2 is a schematic diagram of an antenna structure of a first embodiment of the present invention, FIG. 3 is an exploded schematic diagram of the antenna structure of the first embodiment of the present invention, and FIG. 4 is a schematic diagram of the antenna structure of the first embodiment of the present invention with the metal shell omitted. As shown in FIG. 1 , the present invention provides an electronic device, and the electronic device may be a key module, but the present invention is not limited thereto. The electronic device includes a key cover U and an antenna structure M, and the key cover U is disposed on the antenna structure M. As shown in FIGS. 2 to 4 , the antenna structure M includes a metal shell H, a circuit board 1, a grounded metal part 2, a feed metal part 3, and a first short-circuit metal part 4. It should be noted that the metal shell H may be a part of the outer shell of the electronic device. As shown in FIG3 , the metal housing H has an opening H0. More specifically, one side of the metal housing H forms the opening H0, while the other side is a closed surface, i.e., the bottom H1. In other words, the metal housing H is a housing structure with a single opening. The circuit board 1 is disposed inside the metal housing H and directly opposite to the opening H0, and the grounding metal part 2 and the feeding metal part 3 are disposed on the circuit board 1.

Refer to FIG. 3 and FIG. 5 , FIG. 5 is a schematic diagram of the reverse side of FIG. 4 . The feeding metal part 3 has a grounding terminal 31 and a feeding terminal 32, the grounding terminal 31 is connected to the grounding metal part 2, and the feeding terminal 32 is connected to a signal source (not shown). Therefore, the feeding metal part 3 feeds a signal through the signal source to excite the metal shell H to generate an operating frequency. In the embodiment of the present invention, the operating frequency is between 2.4 and 2.5 GHz, but the present invention is not limited thereto. The first short-circuit metal part 4 has a first end 41 and a second end 42, the first end 41 is connected to the feeding metal part 3, and the second end 42 is connected to the bottom H1 of the metal shell H. Thereby, the antenna structure M of the present invention can perform impedance matching through the design of the first short-circuit metal part 4. Furthermore, when the feeding metal part 3 feeds a signal through the signal source, the first short-circuit metal part 4 is electrically connected to the metal housing H, so that the current can be evenly distributed in the metal housing H, thereby generating good antenna characteristics.

In addition, as shown in FIG5 , the first short-circuit metal part 4 can divide the feeding metal part 3 into a first section and a second section, wherein the first section is a section of the feeding metal part 3 between the feeding end 32 and the first end 41 of the first short-circuit metal part 4, and the second section is a section of the feeding metal part 3 between the grounding end 31 and the first end 41 of the first short-circuit metal part 4. The length of the first section (the length between the feeding end 32 and the first end 41) is shorter than the length of the second section (the length between the grounding end 31 and the first end 41). In other words, the first short-circuit metal part 4 is closer to the feeding end 32 and farther from the grounding end 31. Preferably, the length of the first section is less than 3/4 of the length of the feeding metal part 3 (the sum of the first section and the second section). Preferably, the length of the feed metal part 3 is between 10 mm and 30 mm.

The antenna structure M further includes a second short-circuit metal part 5 and a third short-circuit metal part 6. One end of each of the second short-circuit metal part 5 and the third short-circuit metal part 6 is connected to the grounded metal part 2, and the other end is connected to the bottom H1 of the metal housing H. A resonant path P is generated between the second short-circuit metal part 5 and the third short-circuit metal part 6 along the contour of the metal housing H at the opening H0. The length of the resonant path P is between 0.3 and 0.7 times the wavelength of the operating frequency. Preferably, the length of the resonant path P is 1/2 the wavelength of the operating frequency. In other words, the operating frequency can be determined by the length of the resonant path P. Therefore, the antenna structure M of the present invention can adjust the operating frequency by changing the positions of the second short-circuit metal portion 5 and the third short-circuit metal portion 6 without changing the overall size.

Refer to FIG. 6 , which is a top view schematic diagram of the antenna structure of the first embodiment of the present invention. For example, the grounding metal part 2 can be a metal copper foil laid on the surface of the circuit board 1, and the feeding metal part 3 can be a ring-shaped metal wire or a metal copper foil, but the present invention is not limited thereto. The area on the circuit board 1 where the grounding metal part 2 is laid can be regarded as a wiring area, which can be used for circuit wiring and circuit element configuration. For example, an RF chip can be configured on the wiring area as a signal source, and the RF chip is electrically connected to the feeding end 32 of the feeding metal part 3 by means of circuit wiring.

In addition, the range on the circuit board 1 where the grounding metal part 2 is not laid can be regarded as a clear area, and the feeding metal part 3 is arranged in this range. However, it should be noted that circuit components can also be arranged in the range on the circuit board 1 where the grounding metal part 2 is not laid. The feeding metal part 3 surrounds a accommodating area C in the clear area of the circuit board 1. More specifically, the accommodating area C is the area between the feeding metal part 3 and the grounding metal part 2. A component B can be arranged in the accommodating area C. Component B can be, for example, a metal button, but the present invention is not limited thereto. There is a distance G between component B and the feeding metal part 3. Preferably, the distance G is greater than 1 mm. Therefore, in the present invention, the circuit board 1 of the antenna structure M is not limited to only routing circuits and configuring circuit components in the routing area, but components can also be configured in an appropriate range of the clear area (accommodating area C), thereby greatly increasing the space utilization of the circuit board 1.

Refer to FIG. 7 , which is a schematic diagram of the back side of the antenna structure of the second embodiment of the present invention. The antenna structure M may also include at least one inductor element. The at least one inductor element is connected between the second short-circuit metal part 5 and the grounded metal part 2 or between the third short-circuit metal part 6 and the grounded metal part 2, and the present invention is not limited to the number of at least one inductor element. In this embodiment, the antenna structure M includes a first inductor element 71 and a second inductor element 72. The first inductor element 71 is connected between the second short-circuit metal part 5 and the grounded metal part 2, and the second inductor element 72 is connected between the third short-circuit metal part 6 and the grounded metal part 2. In other words, in the present embodiment, the grounded metal part 2 does not directly contact the second short-circuit metal part 5 and the third short-circuit metal part 6, but electrically connects the second short-circuit metal part 5 and the third short-circuit metal part 6 through the first inductor element 71 and the second inductor element 71. Preferably, the inductance values of the first inductor element 71 and the second inductor element 7 are between 0 nF and 15 nF. Thus, the present invention can utilize the configuration of the first inductor element 71 and the second inductor element 71 to properly adjust the operating frequency generated by the antenna structure M.

Next, refer to FIG. 8 , which is a schematic diagram of the antenna structure of the third embodiment of the present invention. The feeding metal part 3 of FIG. 8 is in a U-shape, and the feeding metal part 3 is centrally arranged on one side of the clear area of the circuit board 1, so that the clear area has more space for configuring other circuit components. Therefore, the antenna structure M of the present invention can greatly increase the space utilization rate on the circuit board 1 by the shape design of the feeding metal part 3 (such as the ring structure of the first embodiment and the U-shaped structure of the third embodiment).

In summary, the antenna structure M of the present invention and the electronic device applicable to the antenna structure M can generate the required operating frequency by arranging a circuit board 1 in a metal shell H having an opening H0, and arranging a grounding metal part 2, a feeding metal part 3, a first short-circuit metal part 4, a second short-circuit metal part 5 and a third short-circuit metal part 6 on the circuit board 1. The antenna structure in the prior art usually uses the metal shell as a reflector, so the directivity of the radiation field is higher. Compared with the prior art, the antenna structure M of the present invention uses the metal shell H as the antenna radiator, so the directivity is lower and can be applied to a variety of different usage scenarios of electronic devices. In addition, in the present invention, the metal housing H and the opening H0 of the antenna structure M are an integrally formed structure, and thus have sufficient structural strength.

Furthermore, the antenna structure M of the present invention is designed to electrically connect the metal housing H through the first short-circuit metal part 4, so that the dead angle of the radiation pattern generated by the antenna structure M is relatively small, that is, the coverage rate of the radiation pattern of the antenna structure M is better. Referring to Figures 9 to 11, Figure 9 is a schematic diagram of the radiation pattern of the antenna structure of the present invention in the XZ plane, Figure 10 is a schematic diagram of the radiation pattern of the antenna structure of the present invention in the YZ plane, and Figure 11 is a schematic diagram of the radiation pattern of the antenna structure of the present invention in the XY plane. The dotted line represents the radiation pattern generated by the monopole antenna structure of the prior art, and the solid line represents the radiation pattern generated by the antenna structure M of the present invention. As shown in FIG. 9 to FIG. 11 , the pattern coverage of the antenna structure M of the present invention in the XZ plane and the XY plane is significantly better than that of the antenna of the prior art.

Furthermore, compared to the slot antenna structure of the prior art which requires metal clearance areas to be formed on the upper and lower sides of the antenna, the antenna structure M of the present invention only forms an opening H0 on one side of the metal housing H (i.e., only forms a metal clearance area on one side of the metal housing H) to achieve good antenna performance. In addition, since the antenna structure M of the present invention uses a ring-shaped feed metal portion 3 to excite the metal housing H, circuit wiring and circuit components can be arranged on both the upper and lower sides of the circuit board 1, thereby greatly increasing space utilization.

The above disclosed contents are only the preferred feasible embodiments of the present invention, and do not limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made by using the contents of the description and drawings of the present invention are included in the scope of the patent application of the present invention.

U: Button cover M: Antenna structure H: Metal housing H0: Opening H1: Bottom 1: Circuit board 2: Ground metal part 3: Feed metal part 31: Ground end 32: Feed end 4: First short-circuit metal part 41: First end 42: Second end 5: Second short-circuit metal part 6: Third short-circuit metal part 71: First inductor element 72: Second inductor element P: Resonance path B: Component C: Accommodation area G: Spacing

FIG1 is a schematic diagram of an electronic device of the present invention.

FIG. 2 is a schematic diagram of the antenna structure of the first embodiment of the present invention.

FIG3 is an exploded schematic diagram of the antenna structure of the first embodiment of the present invention.

FIG4 is a schematic diagram of the antenna structure of the first embodiment of the present invention.

FIG. 5 is a schematic diagram of the reverse side of FIG. 4 .

FIG. 6 is a schematic top view of the antenna structure of the first embodiment of the present invention.

FIG. 7 is a schematic diagram of the back side of the antenna structure of the second embodiment of the present invention.

FIG8 is a schematic diagram of an antenna structure according to a third embodiment of the present invention.

FIG. 9 is a schematic diagram of the radiation pattern of the antenna structure of the present invention in the XZ plane.

FIG10 is a schematic diagram of the radiation pattern of the antenna structure of the present invention in the YZ plane.

FIG. 11 is a schematic diagram of the radiation pattern of the antenna structure of the present invention in the XY plane.

M: Antenna structure

H:Metal shell

H0: Opening

1: Circuit board

2: Grounding metal part

3: Feed the metal part

C: Accommodation area

Claims (10)

An antenna structure includes: a metal shell having an opening; a circuit board disposed in the metal shell and facing the opening; a grounding metal part disposed on the circuit board; a feeding metal part disposed on the circuit board, the feeding metal part having a grounding end and a feeding end, the grounding end being connected to the grounding metal part, and the feeding end being connected to a signal source; a first short-circuit metal part having a first end and a second end, the first end being connected to the feeding metal part, and the second end being connected to the metal shell; and a second short-circuit metal part and a third short-circuit metal part, one end of each of the second short-circuit metal part and the third short-circuit metal part being connected to the grounding metal part and the other end being connected to the metal shell; The feeding metal part is used to feed a signal through the signal source to stimulate the metal shell to generate an operating frequency. The antenna structure as described in claim 1, wherein the operating frequency is between 2.4 and 2.5 GHz. An antenna structure as described in claim 1, wherein a resonance path is generated between the second short-circuit metal part and the third short-circuit metal part along the outline of the metal shell, and the length of the resonance path is between 0.3 times and 0.7 times the wavelength of the operating frequency. The antenna structure as described in claim 1 further includes at least one inductor element, which is connected between the second short-circuit metal part and the ground metal part or between the third short-circuit metal part and the ground metal part. The antenna structure as described in claim 4, wherein the inductance value of the at least one inductor element is between 0 nF and 15 nF. An antenna structure as described in claim 4, wherein the at least one inductor element includes a first inductor element and a second inductor element, and the first inductor element and the second inductor element are respectively connected between the second short-circuit metal part and the ground metal part and between the third short-circuit metal part and the ground metal part. An antenna structure as described in claim 1, wherein a length of the feed metal portion between the feed end and the first end of the first short-circuit metal portion is smaller than a length of the feed metal portion between the ground end and the first end of the first short-circuit metal portion. An antenna structure as described in claim 7, wherein the length between the feed end and the first end of the first short-circuit metal portion is less than 3/4 times the length of the feed metal portion. The antenna structure as described in claim 1, wherein the feeding metal part surrounds the circuit board to form a receiving area, the receiving area is used to receive a component, and the distance between the component and the feeding metal part is greater than 1 mm. An electronic device comprising: The antenna structure described in any one of claims 1 to 9; and A key cover disposed on the antenna structure.

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