CN112825387A

CN112825387A - Antenna structure

Info

Publication number: CN112825387A
Application number: CN201911146783.3A
Authority: CN
Inventors: 黄金莲; 赖国仁
Original assignee: Wistron Neweb Corp
Current assignee: Wistron Neweb Corp
Priority date: 2019-11-21
Filing date: 2019-11-21
Publication date: 2021-05-21

Abstract

The invention discloses an antenna structure, comprising: the circuit board comprises a grounding element, a metal machine component, a feed-in part, a first connecting part, a second connecting part and a short-circuit part. The metal machine component is provided with a slot, wherein the slot is provided with a first edge and a second edge which are opposite. The feeding part extends across the slot, wherein a signal source is coupled to a feeding point on the first edge through the feeding part. The first connecting portion extends across the slot, wherein the first connecting portion is coupled between a first connecting point on the first edge and a second connecting point on the second edge. The second connecting portion extends across the slot, wherein the second connecting portion is coupled between a third connecting point on the first edge and a fourth connecting point on the second edge. A first grounding point on the second edge is coupled to the grounding element through the short-circuit portion.

Description

Antenna structure

Technical Field

The present invention relates to an Antenna Structure (Antenna Structure), and more particularly, to a Wideband (Wideband) Antenna Structure.

Background

With the development of mobile communication technology, mobile devices have become increasingly popular in recent years, such as: portable computers, mobile phones, multimedia players and other portable electronic devices with mixed functions. To meet the demand of people, mobile devices usually have wireless communication functions. Some cover long-distance wireless communication ranges, such as: the mobile phone uses 2G, 3G, LTE (Long Term Evolution) system and its used frequency bands of 700MHz, 850MHz, 900MHz, 1800MHz, 1900MHz, 2100MHz, 2300MHz and 2500MHz for communication, while some cover short-distance wireless communication ranges, for example: Wi-Fi and Bluetooth systems use 2.4GHz, 5.2GHz and 5.8GHz frequency bands for communication.

In order to pursue the aesthetic appearance, designers nowadays often add elements of metal components to mobile devices. However, the added metal elements tend to adversely affect the antenna supporting wireless communication in the mobile device, thereby reducing the overall communication quality of the mobile device. Therefore, there is a need for a new mobile device and antenna structure to overcome the problems encountered in the conventional technology.

Disclosure of Invention

In a preferred embodiment, the present invention provides an antenna structure comprising: a grounding element; a metal machine component having a slot, wherein the slot has a first edge and a second edge opposite to each other; a feeding part extending across the slot, wherein a signal source is coupled to a feeding point on the first edge via the feeding part; a first connection portion extending across the slot, wherein the first connection portion is coupled between a first connection point on the first edge and a second connection point on the second edge; a second connecting portion extending across the slot, wherein the second connecting portion is coupled between a third connecting point on the first edge and a fourth connecting point on the second edge; and a short circuit portion, wherein a first ground point on the second edge is coupled to the ground element via the short circuit portion.

In some embodiments, the slot is a closed slot and has a first closed end and a second closed end.

In some embodiments, the slot substantially exhibits an L-shape.

In some embodiments, the metallic mechanism includes a sidewall portion and a top portion that are generally perpendicular to each other, and the slot is formed between the sidewall portion and the top portion.

In some embodiments, the feeding portion is interposed between the first connecting portion and the second connecting portion.

In some embodiments, the antenna structure further comprises: a third connecting portion extending across the slot, wherein the third connecting portion is coupled between a fifth connecting point on the first edge and a sixth connecting point on the second edge.

In some embodiments, the antenna structure further comprises an adjustment element comprising: a first impedance path; a second impedance path; a third impedance path; a fourth impedance path; and a switching circuit for selecting one of the first impedance path, the second impedance path, the third impedance path, and the fourth impedance path as a target path according to a control signal, such that a second ground point on the second edge is coupled to the ground element via the target path.

In some embodiments, the first impedance path is an open path.

In some embodiments, the second impedance path is a short circuit path.

In some embodiments, the third impedance path is a capacitive path.

In some embodiments, the fourth impedance path is an inductive path.

In some embodiments, the feeding portion is interposed between the short circuit portion and the adjusting element.

In some embodiments, the antenna structure covers a first frequency band between 700MHz to 960MHz, a second frequency band between 1710MHz to 2690MHz, and a third frequency band between 3300MHz to 4200 MHz.

In some embodiments, the length of the slot is approximately equal to 0.25 wavelengths of the lowest frequency of the first frequency band.

In some embodiments, the slot has a width between 1mm and 2 mm.

In some embodiments, the sidewall portion of the metal machine component has a height between 4mm and 6 mm.

In some embodiments, the grounding element is spaced from the sidewall portion of the metal machine component by between 1mm and 2 mm.

Drawings

Fig. 1 is a perspective view of an antenna structure according to an embodiment of the present invention;

FIG. 2 is an equivalent circuit diagram of an adjusting element according to an embodiment of the invention;

fig. 3 is a radiation efficiency diagram of an antenna structure according to an embodiment of the present invention;

fig. 4 is a radiation efficiency diagram of an antenna structure according to an embodiment of the present invention;

fig. 5 is a perspective view of an antenna structure according to another embodiment of the present invention.

Description of the symbols

100. 500-an antenna structure;

110-a grounding element;

120-metal machine components;

125-side wall portions of metal machine components;

126-top surface portion of metal machine component;

130-slotted holes;

131 to the first closed end of the slot;

132 to a second closed end of the slot;

133-a first edge of a slot;

134 to the second edge of the slot;

140 to a feed-in part;

150 to a first connection;

160-a second connecting part;

170 to a third connecting part;

180-short circuit part;

190 to an adjusting element;

191 to a first impedance path;

192 to a second impedance path;

193 to a third impedance path;

194 to a fourth impedance path;

195-a switching circuit;

199-signal source;

CC1 — first curve;

CC 2-second curve;

CC 3-third curve;

CC 4-fourth curve;

CP 1-first connection point;

CP 2-second connection point;

CP 3-third connection point;

CP 4-fourth connection point;

CP 5-fifth connection point;

CP 6-sixth connection point;

d1-spacing;

d2-a first spacing;

d3-second spacing;

d4-third spacing;

d5-fourth spacing;

FP-feed point;

GP 1-first short circuit point;

GP2 second short circuit point;

h1-height;

l1-length;

SC-control signal;

w1-width;

X-X axis;

Y-Y axis;

Z-Z axis.

Detailed Description

In order to make the objects, features and advantages of the present invention comprehensible, specific embodiments accompanied with figures are described in detail below.

Certain terms are used throughout the description and following claims to refer to particular components. As one skilled in the art will appreciate, manufacturers may refer to a component by different names. The present specification and claims do not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. The term "substantially" refers to a range of acceptable error within which one skilled in the art can solve the technical problem to achieve the basic technical result. In addition, the term "coupled" is used herein to encompass any direct or indirect electrical connection. Thus, if a first device couples to a second device, that connection may be through a direct electrical connection, or through an indirect electrical connection via other devices and connections.

Fig. 1 is a perspective view illustrating an Antenna Structure (Antenna Structure)100 according to an embodiment of the invention. The antenna structure 100 can be applied to a Mobile Device (Mobile Device), for example: a Smart Phone (Smart Phone), a Tablet Computer (Tablet Computer), or a Notebook Computer (Notebook Computer). In the embodiment of fig. 1, the antenna structure 100 includes: a Ground Element (Ground Element)110, a Metal mechanical Element (Metal mechanical Element)120, a Feeding Element (Feeding Element)140, a first Connection Element (Connection Element)150, a second Connection Element 160, a third Connection Element 170, a short circuit Element (short Element)180, and an adjusting Element (flexible Element)190, wherein the Ground Element 110, the Feeding Element 140, the first Connection Element 150, the second Connection Element 160, the third Connection Element 170, and the short circuit Element 180 are all made of Metal materials, such as: copper, silver, aluminum, iron, or alloys thereof.

The Ground element 110 may be a System Ground Plane (System Ground Plane) of the antenna structure 100, which may be used to provide a Ground Voltage (VSS) (e.g., 0V). In some embodiments, the grounding element 110 is a grounding metal plane and is disposed on a Dielectric Substrate (Dielectric Substrate), for example: a FR4 (film retadant 4) substrate or a Printed Circuit Board (PCB).

The metal machine component 120 may be a three-dimensional structure. In some embodiments, the metal machine component 120 includes a sidewall portion 125 and a top portion 126 that are generally perpendicular to each other. For example, the sidewall portions 125 can be distributed in the XZ plane and the YZ plane, while the top portion 126 can be distributed in the XY plane. The sidewall portion 125 of the metal machine member 120 may be an appearance element of a mobile device. By "appearance element" is meant a portion of the mobile device that is directly visible to the user's eyes when the mobile device including the antenna structure 100 is viewed by the user. In addition, the metal machine member 120 has a Slot 130 formed between the sidewall portion 125 and the top surface portion 126. The slot 130 may substantially present an L-shape. For example, the Slot 130 may be a Closed Slot (Closed Slot) and has a first Closed end 131 and a second Closed end 132. In detail, the slot 130 has a first edge 133 and a second edge 134 opposite to each other, which are disposed between the first closed end 131 and the second closed end 132. However, the present invention is not limited thereto. In other embodiments, the metal machine component 120 can be modified to have a planar structure, such that the sidewall portion 125, the top portion 126, and the slot 130 can all be located on the same plane.

The feeding portion 140 may be substantially in the shape of a straight bar or a rectangle. The Feeding element 140 extends across the slot 130 of the metal machine component 120, wherein a Signal Source (Signal Source)199 is coupled to a Feeding Point (Feeding Point) FP on the first edge 133 through the Feeding element 140. For example, the signal source 199 may be a Radio Frequency (RF) module that may be used to excite the antenna structure 100.

The first connection portion 150 may have a substantially straight bar shape or a rectangular shape. The first connection portion 150 extends across the slot 130 of the metal machine member 120. In detail, the first Connection portion 150 is coupled between a first Connection Point (Connection Point) CP1 on the first edge 133 and a second Connection Point CP2 on the second edge 134.

The second connection portion 160 may have a substantially straight bar shape or a rectangular shape. The second connecting portion 160 extends across the slot 130 of the metal machine member 120. In detail, the second connecting portion 160 is coupled between a third connection point CP3 on the first edge 133 and a fourth connection point CP4 on the second edge 134, wherein the third connection point CP3 and the fourth connection point CP4 are different from the first connection point CP1 and the second connection point CP 2. In some embodiments, the feeding part 140 is interposed between the first connection part 150 and the second connection part 160.

The third connection portion 170 may have a substantially straight bar shape or a rectangular shape. The third connecting portion 170 extends across the slot 130 of the metal machine member 120. In detail, the third connecting portion 170 is coupled between a fifth connecting point CP5 on the first edge 133 and a sixth connecting point CP6 on the second edge 134, wherein the fifth connecting point CP5 and the sixth connecting point CP6 are different from the first connecting point CP1, the second connecting point CP2, the third connecting point CP3, and the fourth connecting point CP 4. It should be noted that the third connecting portion 170 is an Optional element (Optional), and may be removed in other embodiments.

The short circuit portion 180 may have a bent structure or a planar structure. A first ground Point (connecting Point) GP1 on the second edge 134 is coupled to the ground element 110 via the short circuit portion 180.

The adjustment element 190 may have a bent structure or a planar structure. In some embodiments, the feeding part 140 is interposed between the short circuit part 180 and the adjusting element 190. Fig. 2 is an equivalent circuit diagram of an adjusting element 190 according to an embodiment of the invention. The adjusting element 190 includes a first Impedance Path (Impedance Path)191, a second Impedance Path 192, a third Impedance Path 193, a fourth Impedance Path 194, and a Switch Circuit (Switch Circuit) 195. The first impedance path 191, the second impedance path 192, the third impedance path 193, and the fourth impedance path 194 may have different impedance values, and they may be respectively coupled to the ground potential VSS of the ground element 110. One end of the switching circuit 195 is coupled to a second grounding point GP2 on the second edge 134, and the other end of the switching circuit 195 switches among the first impedance path 191, the second impedance path 192, the third impedance path 193, and the fourth impedance path 194, wherein the second grounding point GP2 is different from the first grounding point GP 1. In detail, the switching circuit 195 selects one of the first impedance Path 191, the second impedance Path 192, the third impedance Path 193, and the fourth impedance Path 194 as a Target Path (Target Path) according to a control signal SC, such that the second ground point GP2 can be coupled to the ground element 110 via the Target Path. For example, the control signal SC may be generated by a Processor (Processor) according to a user input. In some embodiments, the first impedance Path 191 is an Open-circuit Path (Open-circuit Path), the second impedance Path 192 is a Short-circuit Path (Short-circuit Path), the third impedance Path 193 is a Capacitive Path (Capacitive Path), and the fourth impedance Path 194 is an Inductive Path (Inductive Path), but is not limited thereto. It should be noted that the adjustment element 190 is an optional element and may be removed in other embodiments.

Fig. 3 is a diagram illustrating Radiation Efficiency (Radiation Efficiency) of the antenna structure 100 according to an embodiment of the present invention. According to the measurement results shown in fig. 3, the antenna structure 100 can cover a first Frequency Band (Frequency Band), a second Frequency Band, and a third Frequency Band, wherein the first Frequency Band can be between 700MHz and 960MHz, the second Frequency Band can be between 1710MHz and 2690MHz, and the third Frequency Band can be between 3300MHz and 4200 MHz. Therefore, the antenna structure 100 can support at least the wideband operation of lte (long Term evolution) and new generation 5G systems. In addition, the radiation efficiency of the antenna structure 100 in the above frequency bands can reach 40% or more, which can meet the practical application requirements of the general mobile communication device.

In some embodiments, the principles of operation of the antenna structure 100 may be as follows. The slot 130 of the metal machine component 120 is excited by the feeding element 140 to generate the first frequency band, the second frequency band, and the third frequency band. In detail, the entire slot 130 between the first closed end 131 and the second closed end 132 may correspond to the aforementioned first frequency band; a portion of the slot 130 between the first connection portion 150 and the second connection portion 160 may correspond to the second frequency band; another portion of the slot 130 between the third connecting portion 170 and the feeding portion 140 may correspond to the third frequency band. According to the actual measurement result, the addition of the first connection portion 150, the second connection portion 160, and the third connection portion 170 helps to fine tune the equivalent resonance length of the slot 130, so as to increase the high frequency Operation Bandwidth (Operation Bandwidth) of the antenna structure 100 (especially for the second frequency band and the third frequency band).

Fig. 4 is a diagram illustrating Radiation Efficiency (Radiation Efficiency) of the antenna structure 100 according to an embodiment of the present invention. As shown in fig. 4, a first curve CC1 represents the operating characteristics of the antenna structure 100 when the switching circuit 195 selects the first impedance path 191, a second curve CC2 represents the operating characteristics of the antenna structure 100 when the switching circuit 195 selects the second impedance path 192, a third curve CC3 represents the operating characteristics of the antenna structure 100 when the switching circuit 195 selects the third impedance path 193, and a fourth curve CC4 represents the operating characteristics of the antenna structure 100 when the switching circuit 195 selects the fourth impedance path 194. In the embodiment of fig. 4, the first impedance path 191 is an open circuit path, the second impedance path 192 is a larger inductive path (e.g., 9.1nH), the third impedance path 193 is a medium inductive path (e.g., 1nH), and the fourth impedance path 194 is a smaller inductive path (e.g., 0.5 nH). According to the measurement results of fig. 4, the antenna structure 100 can effectively expand the low frequency operation bandwidth (especially for the first frequency band) by using the adjusting element 190 for switching.

In some embodiments, the element dimensions of the antenna structure 100 may be as follows. The length L1 of the slot 130 of the metal machine member 120 (i.e., the length from the first closed end 131 to the second closed end 132) may be substantially equal to 0.25 times the wavelength (λ/4) of the lowest frequency of the first frequency band of the antenna structure 100. The width W1 of the slot 130 of the metal machine component 120 (i.e., the spacing between the first edge 133 and the second edge 134) may be between 1mm and 2 mm. The height H1 of the sidewall portion 125 of the metal machine component 120 may be between 4mm and 6mm, for example: about 5 mm. The spacing D1 between the grounding element 110 and the sidewall portion 125 of the metal machine component 120 may be between 1mm and 2mm, for example: about 1.6 mm. The distance from the first connection point CP1 to the feeding point FP may be defined as a first distance D2, and the distance from the third connection point CP3 to the feeding point FP may be defined as a second distance D3, wherein the first distance D2 may be between 1 and 2 times the second distance D3, for example: about 1.8 times. The distance from the sixth connection point CP6 to the first closed end 131 may be defined as a third distance D4, and the distance from the fourth connection point CP4 to the second closed end 132 may be defined as a fourth distance D5, wherein the fourth distance D5 may be between 2 times and 3 times the third distance D4, for example: about 2.2 times. In the tuning element 190, the Capacitance (Capacitance) of the third impedance path 193 may be between 0.5pF and 10pF, and the Inductance (Inductance) of the fourth impedance path 194 may be between 1nH and 36 nH. The parameter ranges of the above elements are calculated from a plurality of experimental results, which helps to optimize the operating bandwidth and impedance matching of the antenna structure 100.

In some embodiments, the grounding element 110 is disposed on a Keyboard Frame (Keyboard Frame), wherein the Keyboard Frame may be referred to as "C-shaped" in the field of notebook computers. When a Base Housing (Base Housing) is disposed opposite to the keyboard bezel, the Base Housing can be made of metal material, but a non-conductive Antenna Window (Antenna Window) is left, so that the Vertical Projection (Vertical Projection) of the slot 130 of the metal machine component 120 is completely located inside the Antenna Window, wherein the "Base Housing" can be referred to as "D-piece" in the notebook computer field. The electromagnetic waves of the antenna structure 100 can be transmitted through the antenna window of the base housing. It should be noted that, according to actual measurement results, the radiation performance of the antenna structure 100 in the desired operating frequency band can be substantially maintained unchanged, regardless of the addition of the base housing.

Fig. 5 is a perspective view illustrating an antenna structure 500 according to another embodiment of the present invention. Fig. 5 is similar to fig. 1. In the embodiment of fig. 5, the antenna structure 500 does not include the aforementioned third connection portion 170 and the adjustment element 190; however, after the element dimensions are properly fine-tuned, the antenna structure 500 can still cover the broadband operation of LTE and 5G, as previously described. The remaining features of the antenna structure 500 of fig. 5 are similar to those of the antenna structure 100 of fig. 1, so that similar operation effects can be achieved in both embodiments.

The present invention provides a novel antenna structure, which can cover a wide frequency band for operation. When the antenna structure is applied to a mobile device with a metal mechanical component, the metal mechanical component can be regarded as an extension part of the antenna structure, so that the metal mechanical component can be effectively prevented from generating negative influence on the communication quality of the mobile device. Compared with the conventional Planar Inverted F Antenna (PIFA), which generally has an overall height of 8mm to 10mm, the overall height of the Antenna structure of the present invention is reduced by about 50%. In summary, the present invention can achieve the advantages of small size, wide frequency band, and beautiful appearance, so it is very suitable for various Narrow frame (Narrow Border) mobile communication devices.

It is noted that the sizes, shapes, and frequency ranges of the above-described elements are not limitations of the present invention. The antenna designer can adjust these settings according to different needs. The antenna structure of the present invention is not limited to the states illustrated in fig. 1 to 5. The present invention may include only any one or more features of any one or more of the embodiments of fig. 1-5. In other words, not all illustrated features may be required to implement the antenna structure of the present invention at the same time.

Ordinal numbers such as "first," "second," "third," etc., in the specification and claims are not necessarily in sequential order, but are merely used to identify two different elements having the same name.

Although the present invention has been described in connection with the preferred embodiments, it is not intended to limit the scope of the invention, and one skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention.

Claims

1. An antenna structure, comprising:

a ground element;

a metal machine component having a slot, wherein the slot has opposing first and second edges;

a feeding part extending across the slot, wherein a signal source is coupled to a feeding point on the first edge via the feeding part;

a first connection portion extending across the slot, wherein the first connection portion is coupled between a first connection point on the first edge and a second connection point on the second edge;

a second connecting portion extending across the slot, wherein the second connecting portion is coupled between a third connection point on the first edge and a fourth connection point on the second edge; and

a short circuit portion, wherein a first ground point on the second edge is coupled to the ground element via the short circuit portion.

2. The antenna structure of claim 1 wherein the slot is a closed slot and has a first closed end and a second closed end.

3. The antenna structure of claim 1 wherein the slot generally exhibits an L-shape.

4. The antenna structure of claim 1 wherein the metal machine member includes a sidewall portion and a top portion that are substantially perpendicular to each other, and the slot is formed between the sidewall portion and the top portion.

5. The antenna structure according to claim 1, wherein the feeding portion is interposed between the first connecting portion and the second connecting portion.

6. The antenna structure of claim 1, further comprising:

a third connecting portion extending across the slot, wherein the third connecting portion is coupled between a fifth connecting point on the first edge and a sixth connecting point on the second edge.

7. The antenna structure of claim 1, further comprising an adjustment element comprising:

a first impedance path;

a second impedance path;

a third impedance path;

a fourth impedance path; and

a switching circuit, for selecting one of the first impedance path, the second impedance path, the third impedance path, and the fourth impedance path as a target path according to a control signal, such that a second ground point on the second edge is coupled to the ground element via the target path.

8. The antenna structure of claim 7 wherein the first impedance path is an open circuit path.

9. The antenna structure of claim 7 wherein the second impedance path is a short circuit path.

10. The antenna structure of claim 7 wherein the third impedance path is a capacitive path.

11. The antenna structure of claim 7 wherein the fourth impedance path is an inductive path.

12. The antenna structure according to claim 7, wherein the feeding portion is interposed between the short-circuit portion and the adjustment element.

13. The antenna structure of claim 1, wherein the antenna structure covers a first frequency band between 700MHz and 960MHz, a second frequency band between 1710MHz and 2690MHz, and a third frequency band between 3300MHz and 4200 MHz.

14. The antenna structure of claim 13 wherein the length of the slot is approximately equal to 0.25 wavelengths of the lowest frequency of the first frequency band.

15. The antenna structure of claim 1 wherein the width of the slot is between 1mm and 2 mm.

16. The antenna structure of claim 4 wherein the sidewall portion of the metal machine member has a height of between 4mm and 6 mm.

17. The antenna structure of claim 4, wherein the spacing between the grounding element and the sidewall portion of the metal machine member is between 1mm and 2 mm.