CN108539366B - Antenna structure - Google Patents

Abstract

An antenna structure. The antenna structure includes a grounding component and a metal ring; the metal ring includes a main radiating part and a floating radiating part; the main radiating part has a feeding point, a first short-circuit point, and a second short-circuit point, wherein the first short-circuit point and the second short-circuit point are both coupled to the grounding component, and wherein the feeding point is approximately between the first short-circuit point and the second short-circuit point; the floating radiating part is adjacent to the main radiating part and is separated from both the grounding component and the main radiating part; wherein the grounding component is approximately surrounded by the metal ring. Compared with the traditional design, the antenna structure of the present invention has the advantages of small size, wide bandwidth, low cost and low manufacturing complexity. In addition, the antenna structure of the present invention can be integrated with the metal appearance component of the device, so it also has the effect of beautifying the appearance of the device and enhancing the fashion sense of the device, so the present invention is very suitable for application in various portable items or wearable devices.

Description

Antenna structure

technical field

The present invention relates to an antenna structure, in particular to an antenna structure that can cover a mobile communication frequency band.

Background technique

With the development of mobile communication technology, mobile devices have become more and more common in recent years, such as portable computers, mobile phones, multimedia players and other portable electronic devices with mixed functions. In order to meet people's needs, mobile devices usually have the function of wireless communication. Some cover long-distance wireless communication range, for example: mobile phones use 2G, 3G, LTE (Long Term Evolution) systems and their use of 700MHz, 850MHz, 900MHz, 1800MHz, 1900MHz, 2100MHz, 2300MHz and 2500MHz frequency bands for communication, while Some cover the short-range wireless communication range, for example: Wi-Fi, Bluetooth systems use the 2.4GHz, 5.2GHz and 5.8GHz frequency bands to communicate.

According to the research directions of various brands, the emerging mobile devices of the next generation are likely to be "Wearable Devices". For example, watches, glasses, and even any paraphernalia have the opportunity to have wireless communication capabilities in the future. However, the internal space of the wearable device is very small, which is often not enough to accommodate the antenna used for wireless communication. Therefore, how to design a small-sized and wide-band antenna structure will become a major challenge for designers.

Therefore, it is necessary to provide an antenna structure to solve the above problems.

SUMMARY OF THE INVENTION

In a preferred embodiment, the present invention provides an antenna structure, the antenna structure includes: a grounding component; and a metal ring, the metal ring includes: a main radiating part, the main radiating part has a feeding point , a first short-circuit point, and a second short-circuit point, wherein the first short-circuit point and the second short-circuit point are both coupled to the ground element, and wherein the feed-in point is approximately between the first short-circuit point and the between the second short-circuit points; and a floating radiating part, the floating radiating part is adjacent to the main radiating part and separated from the grounding element and the main radiating part; wherein the grounding element is substantially surrounded by the metal ring surrounded.

In some embodiments, the main radiating part has a first end and a second end that are far away from each other, the first short-circuit point is located at the first end of the main radiating part, and the second short-circuit point is located in the main radiating part the second end of the part.

In some embodiments, the floating radiating portion has a first end and a second end that are far away from each other, and a first end is formed between the first end of the floating radiating portion and the first end of the main radiating portion a coupling gap, and a second coupling gap is formed between the second end of the floating radiating part and the second end of the main radiating part.

In some embodiments, the antenna structure covers an operating frequency band between 2403 MHz and 2483.5 MHz.

In some embodiments, the main radiating part includes a radiating branch and an adjusting branch, the radiating branch is located between the feeding point and the second short circuit point, and the adjusting branch is located between the feeding point Between the radiation branch and the first short-circuit point, the radiation branch serves as a main resonance path of the antenna structure, and the adjustment branch is used for fine-tuning the impedance matching of the antenna structure.

In some embodiments, the radiating branch extends along an edge of the grounding component such that a slot area is formed between the radiating branch and the grounding component.

In some embodiments, the length of the slot region is approximately equal to 1 wavelength of the center frequency of the operating band.

In some embodiments, the length of the adjustment branch is less than 0.25 wavelengths of the center frequency of the operating band.

In some embodiments, the floating radiating portion acts as a director of the main radiating portion, so that the antenna structure can provide a nearly omnidirectional radiation pattern.

In another preferred embodiment, the present invention provides an antenna structure, the antenna structure includes: a ground component; and a metal ring, the metal ring has a feeding point and a short-circuit point, wherein the short-circuit point is coupled to the ground component; wherein the ground component is substantially surrounded by the metal ring.

In some embodiments, when the antenna structure is excited, a current null will be generated on the metal loop.

In some embodiments, the metal ring includes a radiation branch and an adjustment branch, the radiation branch is between the feeding point and the current zero point, and the adjustment branch is between the feeding point and the current zero Between the short-circuit points, the radiation branch serves as a main resonance path of the antenna structure, and the adjustment branch is used to fine-tune the impedance matching of the antenna structure.

The present invention proposes a novel antenna structure. Compared with the traditional design, the present invention has at least the advantages of small size, wide frequency band, low cost, and low manufacturing complexity. In addition, the antenna structure of the present invention can be integrated with the metal exterior components of the device, so it also has the effect of beautifying the appearance of the device and enhancing the fashion sense of the device, so the present invention is suitable for use in various personal items or wearable devices.

Description of drawings

FIG. 1 is a schematic diagram showing an antenna structure according to an embodiment of the present invention;

FIG. 2 is a schematic diagram showing an antenna structure according to an embodiment of the present invention;

FIG. 3 is a schematic diagram showing an antenna structure according to an embodiment of the present invention; and

FIG. 4 is a schematic diagram illustrating an antenna structure according to an embodiment of the present invention.

Explanation of main component symbols:

100, 200, 300, 400 Antenna Structures

110, 210, 310, 410 Grounding Components

111 Edge of ground component

120, 220, 320, 420 metal ring

130, 230, 330 main radiator

131, 231, 331 The first end of the main radiator

132, 232, 332 The second end of the main radiator

133, 233, 333, 433 Radiation branch

134, 234, 334, 434 Adjustment branch

135, 235, 335 slotted area

140, 240, 340 floating radiation part

141 Floating the first end of the radiating part

142 Floating the second end of the radiator

190 sources

436 Rest of the metal ring

FP feed point

GC1 first coupling gap

GC2 second coupling gap

GP short-circuit point

GP1 first short-circuit point

GP2 Second short-circuit point

L1, L2, L3, L4, L5 length

NP current zero

W1 width

X X axis

Y Y axis

Z Z axis

Detailed ways

In order to make the objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are exemplified below, and are described in detail as follows in conjunction with the accompanying drawings.

Certain terms are used in the specification and claims to refer to particular components. It should be understood by those skilled in the art that hardware manufacturers may refer to the same component by different nouns. The present specification and claims do not use the difference in name as a way to distinguish components, but use the difference in function of the components as a criterion for distinguishing. The words "comprising" and "including" mentioned throughout the specification and claims are open-ended terms and should be interpreted as "including but not limited to". The word "substantially" means that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range and achieve the basic technical effect. Furthermore, the term "coupled" in this specification includes any direct and indirect means of electrical connection. Therefore, if a first device is described as being coupled to a second device, it means that the first device can be directly electrically connected to the second device, or indirectly electrically connected to the second device through other devices or connecting means. Second device.

FIG. 1 is a schematic diagram illustrating an antenna structure 100 according to an embodiment of the present invention. The antenna structure 100 can be applied to a mobile device, a wearable device, or a personal item. In some embodiments, the antenna structure 100 is combined with a key ring, so that the key ring has the function of wireless communication, but the present invention is not limited thereto. In other embodiments, the antenna structure 100 can also be combined with any small object to become a part of an Internet of Things (Internet of Things, IOT). As shown in FIG. 1 , the antenna structure 100 includes a ground element 110 and a metal loop 120 , wherein the ground element 110 is substantially surrounded by the metal loop 120 . For example, the ground element 110 can be a ground copper foil (Ground Copper) on a printed circuit board (Printed Circuit Board, PCB), and the metal ring 120 can be an appearance element (Appearance Element) whose metal visual The properties help to modify and beautify the appearance of the applied device.

The metal ring 120 includes a main radiation element 130 and a floating radiation element 140 , wherein the main radiation element 130 and the floating radiation element 140 both extend along the grounding element 110 . The main radiating part 130 has a feeding point (Feeding Point) FP, a first shorting point (Shorting Point) GP1, and a second shorting point GP2. The feeding point FP is coupled to a signal source 190 . For example, the signal source 190 can be a radio frequency (RF) module, which can be used to generate a transmit signal or process a receive signal. A positive electrode of the signal source 190 can be coupled to the feeding point FP, and a negative electrode of the signal source 190 can be coupled to the ground element 110 . Both the first short-circuit point GP1 and the second short-circuit point GP2 are directly coupled to the ground element 110 . The feeding point FP is approximately between the first short-circuit point GP1 and the second short-circuit point GP2. The floating radiating part 140 is adjacent to the grounding element 110 and the main radiating part 130 and is completely separated from the grounding element 110 and the main radiating part 130 .

In detail, the main radiating part 130 has a first end 131 and a second end 132 that are far away from each other, wherein the first short-circuit point GP1 can be located at the first end 131 of the main radiating part 130, and the second short-circuit point GP2 can be located at the first end 131 of the main radiating part 130 The second end 132 of the main radiating part 130 . The floating radiating part 140 also has a first end 141 and a second end 142 that are far away from each other, wherein a first end 141 of the floating radiating part 140 and the first end 131 of the main radiating part 130 can form a first end A coupling gap GC1 is formed, and a second coupling gap GC2 is formed between the second end 142 of the floating radiation portion 140 and the second end 132 of the main radiation portion 130 . In order to enhance the coupling effect between components, both the width of the first coupling gap GC1 and the width of the second coupling gap GC2 must be less than 20 mm.

In the embodiment of FIG. 1 , the grounding element 110 is substantially a square metal plate, but its four corners are all modified into rounded corners. Correspondingly, the metal ring 120 is roughly a hollow square frame, and its four corners are also modified into arc corners. Specifically, the main radiating portion 130 may be approximately a long U-shape, and the floating radiation portion 140 may be approximately a short U-shape. That is, the total length of the main radiating part 130 may be greater than the total length of the floating radiating part 140 . However, the present invention is not limited to this. In other embodiments, the grounding member 110 and the metal ring 120 may be changed to other different corresponding shapes. For example, the grounding element 110 can be substantially a rectangular metal plate, but the four corners are all left in the shape of a right angle; and the metal ring 120 can be substantially a hollow rectangular frame, and the four corners are also left in the shape of a right angle. In other embodiments, at least one of the corners of the ground component 110 may form a truncated corner.

According to the actual measurement results, when the antenna structure 100 is excited, the antenna structure 100 can cover an operating frequency band, wherein the operating frequency band can be between 2403MHz and 2483.5MHz. Therefore, the antenna structure 100 will support at least the Mobile Communication Frequency Band using Bluetooth or Wi-Fi.

In detail, the main radiation part 130 includes a radiation branch 133 and a tuning branch 134, wherein the radiation branch 133 is between the feeding point FP and the second short-circuit point GP2, and The adjusting branch 134 is between the feeding point FP and the first short-circuit point GP1. The radiation branch 133 may be substantially C-shaped. The adjusting branch 134 may be substantially in the shape of a straight bar. The radiation branch 133 extends along an edge 111 of the grounding component 110, so that a slot region 135 is formed between the radiation branch 133 and the grounding component 110, wherein the slot region 135 is a metal-free clearance area, There will be no metal components inside.

In terms of the antenna principle, the radiation branch 133 is a part of the antenna structure 100 with a higher current density and serves as a main resonant path of the antenna structure 100; and the adjustment branch 134 is used to provide an inductance Inductance, to fine-tune the impedance matching of the antenna structure 100 (Impedance Matching). One end of the radiation branch 133 is the feeding point FP, and the other end is the first short-circuit point GP1 coupled to the ground element 110 , so the combination of the radiation branch 133 and the ground element 110 can be regarded as a loop antenna (Loop Antenna) . In addition, the slot area 135 between the radiation branch 133 and the ground element 110 can be regarded as a slot antenna. Under this design, the antenna structure 100 can be used as a hybrid antenna including a loop antenna and a slot antenna. By integrating two different antenna types, the antenna structure 100 can enjoy a better radiation pattern of a slot antenna. (Radiation Pattern), while having a larger operating bandwidth (Operation Bandwidth) of the cyclic antenna. On the other hand, the floating radiating portion 140 can be used as a director of the main radiating portion 130 to correct the radiation pattern of the antenna structure 100 . For example, when the main radiation directions of the antenna structure 100 are the front and rear directions (the +Z-axis and -Z-axis directions in FIG. 1 ), the floating radiating portion 140 can be coupled and excited by the main radiating portion 130 , and the The coupling current can generate radiation in side directions (eg, toward the +X axis and -X axis directions in FIG. 1 ), so that the antenna structure 100 can provide an approximately omnidirectional radiation pattern. Therefore, the antenna structure 100 can easily receive and transmit wireless signals in various directions.

In terms of component size, the length L1 of the slot region 135 is approximately equal to 1 wavelength (1λ) of the center frequency of the operating frequency band of the antenna structure 100 , and the width W1 of the slot region 135 is greater than or equal to 2 mm. The aforementioned limited ranges of length L1 and width W1 help to maintain the broadband characteristics of the antenna structure 100 (for example, if the width W1 of the slot region 135 is insufficient, the bandwidth of the slot antenna will become narrower). Because the radiation branch 133 is close to the slot area 135 , the length L2 of the radiation branch 133 is almost equal to (or slightly larger than) the length L1 of the slot area 135 . In order to provide sufficient inductance characteristics, the length L3 of the adjustment branch 134 must be less than 0.25 wavelengths (0.25λ) of the center frequency of the operating frequency band of the antenna structure 100 . The above size ranges are summarized based on multiple experimental results, which can optimize the operating frequency band and impedance matching of the antenna structure 100 .

It must be understood that the shapes of the ground component 110 and the metal ring 120 of the antenna structure 100 are not limitations of the present invention, and can be adjusted according to different appearance requirements. The following embodiments will illustrate the design of antenna structures with different shapes, but the operating principles are generally the same as the antenna structure 100 in FIG. 1 .

FIG. 2 shows a schematic diagram of an antenna structure 200 according to an embodiment of the present invention. Figure 2 is similar to Figure 1 . In the embodiment of FIG. 2 , a grounding element 210 of the antenna structure 200 is substantially a circular metal plate, and a metal ring 220 of the antenna structure 200 is substantially a hollow circular frame for correspondingly accommodating the circular grounding component 210. The remaining features of the antenna structure 200 of FIG. 2 are similar to those of the antenna structure 100 of FIG. 1 , so the two embodiments can achieve similar operating effects.

FIG. 3 shows a schematic diagram of an antenna structure 300 according to an embodiment of the present invention. Figure 3 is similar to Figure 1 . In the embodiment of FIG. 3 , a grounding element 310 of the antenna structure 300 is substantially a triangular metal plate, and a metal ring 320 of the antenna structure 300 is substantially a hollow triangular frame for correspondingly accommodating the triangular grounding element 310 . The remaining features of the antenna structure 300 of FIG. 3 are similar to those of the antenna structure 100 of FIG. 1 , so the two embodiments can achieve similar operating effects.

FIG. 4 shows a schematic diagram of an antenna structure 400 according to an embodiment of the present invention. Antenna structure 400 may be viewed as a simplified version of antenna structure 100 of FIG. 1, although it may also provide similar operating characteristics. For example, the antenna structure 400 can cover an operating frequency band, and the operating frequency band can also be between 2403MHz and 2483.5MHz. In the embodiment of FIG. 4 , the antenna structure 400 includes a ground element 410 and a metal ring 420 , wherein the ground element 410 is substantially surrounded by the metal ring 420 . It must be noted that the metal ring 420 does not have any disconnection or coupling gap, but presents a complete loop shape, which further reduces the manufacturing complexity of the antenna structure 400 . The metal ring 420 has a feed-in point FP and a short-circuit point GP, wherein the feed-in point FP is coupled to a signal source 190 , and the short-circuit point GP is coupled to the ground element 410 . When the antenna structure 400 is excited, a current null (Current Null) NP will be generated on the metal ring 420, wherein the current density at the current null point NP is almost zero, which can be regarded as a virtual short-circuit point. In detail, the metal ring 420 includes a radiation branch 433 and an adjustment branch 434, wherein the radiation branch 433 is between the feeding point FP and the current zero point NP, and the adjusting branch 434 is between the feeding point FP and short-circuit point GP. The total length of the radiation branch 433 is much larger than the total length of the adjustment branch 434 . For example, the total length of the radiation branch 433 may be at least more than three times the total length of the adjustment branch 434 . In terms of the antenna principle, the radiation branch 433 is a part of the antenna structure 400 with a high current density, and serves as a main resonance path of the antenna structure 400 ; and the adjustment branch 434 is used to provide inductance characteristics to fine-tune the impedance of the antenna structure 400 match. It should be noted that the current density on the remaining portion 436 of the metal ring 420 is relatively low, so it has little effect on the radiation characteristics of the antenna structure 400 . In terms of component size, the length L4 of the radiation branch 433 may be approximately equal to 1 wavelength of the center frequency of the operating frequency band of the antenna structure 400 , and the length L5 of the adjusting branch 434 may be less than 0.25 of the center frequency of the operating frequency band of the antenna structure 400 times the wavelength. The remaining features of the antenna structure 400 of FIG. 4 are similar to those of the antenna structure 100 of FIG. 1 , so the two embodiments can achieve similar operating effects.

The present invention proposes a novel antenna structure. Compared with the traditional design, the present invention has at least the advantages of small size, wide frequency band, low cost, and low manufacturing complexity. In addition, the antenna structure of the present invention can be integrated with the metal exterior components of the device, so it also has the effect of beautifying the appearance of the device and enhancing the fashion sense of the device, so the present invention is suitable for use in various personal items or wearable devices.

It should be noted that the above-mentioned component size, component shape, and frequency range are not limitations of the present invention. Antenna designers can adjust these settings according to different needs. The antenna structure of the present invention is not limited to the states illustrated in FIGS. 1 to 4 . The present invention may include only any one or more features of any one or more of the embodiments of Figures 1-4. In other words, not all of the illustrated features must be simultaneously implemented in the antenna structure of the present invention.

The ordinal numbers in this specification and the claims, such as "first", "second", "third", etc., do not have a sequential relationship with each other, and are only used to indicate and distinguish two identical different components of the name.

Although the present invention is disclosed above with preferred embodiments, it is not intended to limit the scope of the present invention. Any person of ordinary skill in the art should be able to make some changes without departing from the spirit and scope of the present invention. and modifications, therefore the scope of protection of the present invention should be defined by the appended claims.

Claims (12)

1. An antenna structure, comprising:

a grounding assembly; and

a metal collar, the metal collar comprising:

a main radiation part having a feed point, a first short point, and a second short point, wherein the first short point and the second short point are both coupled to the grounding component, and the feed point is between the first short point and the second short point; and

a floating radiation part, which is adjacent to the main radiation part and separated from the grounding component and the main radiation part;

wherein the grounding element is surrounded by the metal ring;

the main radiation part comprises an adjusting branch which is arranged between the feed-in point and the first short-circuit point and is used for fine tuning the impedance matching of the antenna structure.

2. The antenna structure of claim 1, wherein the main radiating portion has a first end and a second end that are far away from each other, the first short point is located at the first end of the main radiating portion, and the second short point is located at the second end of the main radiating portion.

3. The antenna structure of claim 2, wherein the floating radiating portion has a first end and a second end that are far away from each other, a first coupling gap is formed between the first end of the floating radiating portion and the first end of the main radiating portion, and a second coupling gap is formed between the second end of the floating radiating portion and the second end of the main radiating portion.

4. The antenna structure of claim 1 wherein the antenna structure covers an operating band between 2403MHz and 2483.5 MHz.

5. The antenna structure of claim 4, wherein the main radiating portion further comprises a radiating branch interposed between the feeding point and the second short-circuit point, the radiating branch serving as a main resonant path of the antenna structure.

6. The antenna structure of claim 5, wherein the radiating branch extends along an edge of the ground element such that a slot region is formed between the radiating branch and the ground element.

7. The antenna structure of claim 6 wherein the length of the slot region is approximately equal to 1 wavelength of the center frequency of the operating band.

8. The antenna structure of claim 5 wherein the length of the tuning branch is less than 0.25 wavelengths of the center frequency of the operating band.

9. The antenna structure of claim 1, wherein the floating radiating portion acts as a director for the main radiating portion, such that the antenna structure provides an approximately omnidirectional radiation pattern.

10. An antenna structure, comprising:

a grounding assembly; and

a metal ring having a feed point and a shorting point, wherein the shorting point is coupled to the ground element;

wherein the grounding element is surrounded by the metal ring;

wherein the metal loop includes an adjustment branch interposed between the feed point and the short circuit point, the adjustment branch being for fine tuning the impedance matching of the antenna structure.

11. The antenna structure of claim 10 wherein a current null is created on the metallic loop when the antenna structure is excited.

12. The antenna structure of claim 11, wherein the metal loop further comprises a radiating branch interposed between the feed point and the current zero, the radiating branch serving as a primary resonant path of the antenna structure.

Images