CN115498397A - Antenna structure - Google Patents

Abstract

The invention discloses an antenna structure, comprising: the antenna comprises a grounding element, a first radiation part, a second radiation part, a medium substrate, a first feed-in part, a second feed-in part, a third feed-in part and a fourth feed-in part. The dielectric substrate has a first surface and a second surface opposite to each other, wherein the first radiating portion is disposed on the first surface, and the grounding element is disposed on the second surface. The second radiation part is adjacent to the first radiation part and separated from the first radiation part. The first feeding part has a first feeding port and is coupled to the first radiating part. The second feeding part has a second feeding port and is coupled to the first radiating part. The third feeding part has a third feeding port and is coupled to the first radiating part. The fourth feeding part has a fourth feeding port and is coupled to the first radiating part.

Description

Antenna structure

Technical Field

The present invention relates to an antenna structure, and more particularly, to a multi-feed 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 range covers long distance wireless communication, for example: mobile phones use 2G, 3G, LTE (Long Term Evolution) systems and the frequency bands used by them, such as 700MHz, 850MHz, 900MHz, 1800MHz, 1900MHz, 2100MHz, 2300MHz and 2500MHz, while some cover short-distance wireless communication ranges, such as: wi-Fi and Bluetooth systems use 2.4GHz, 5.2GHz and 5.8GHz frequency bands for communication.

A Wireless Access Point (Wireless Access Point) is a necessary component for enabling a mobile device to Access internet indoors at a high speed. However, since the indoor environment is full of signal reflections and Multipath Fading (Multipath Fading), the wireless network base station must be able to process signals from all directions and all polarizations simultaneously. Therefore, it has become a challenge to design a wide-band multi-polarization antenna in the limited space of the wireless network base station.

Disclosure of Invention

In a preferred embodiment, the present invention provides an antenna structure comprising: a grounding element; a first radiation part; a dielectric substrate having a first surface and a second surface opposite to each other, wherein the first radiating portion is disposed on the first surface, and the grounding element is disposed on the second surface; a second radiation part adjacent to the first radiation part and separated from the first radiation part; a first feed-in part having a first feed-in port and coupled to the first radiation part; a second feed-in part having a second feed-in port and coupled to the first radiation part; a third feeding part having a third feeding port and coupled to the first radiation part; and a fourth feed-in part having a fourth feed-in port and coupled to the first radiating part; wherein the antenna structure covers an operating frequency band.

In some embodiments, the operating band is between 2400MHz to 2500 MHz.

In some embodiments, the first radiating portion has a circular shape.

In some embodiments, the radius of the first radiating portion is approximately equal to 0.25 guide wavelengths of the operating band.

In some embodiments, the first radiating portion presents a regular octagon.

In some embodiments, the first radiation portion further has a first notch, a second notch, a third notch and a fourth notch, which respectively correspond to the first feed-in portion, the second feed-in portion, the third feed-in portion and the fourth feed-in portion.

In some embodiments, the second radiating portion exhibits another circular shape, and the area of the second radiating portion is larger than the area of the first radiating portion.

In some embodiments, the radius of the second radiating portion is approximately equal to 0.25 free-space wavelengths of the operating band.

In some embodiments, the second radiating portion is substantially parallel to the first radiating portion, and a coupling gap is formed between the second radiating portion and the first radiating portion.

In some embodiments, the width of the coupling gap is approximately equal to 0.05 free-space wavelengths of the operating band.

In some embodiments, the lengths of the first feeding element, the second feeding element, the third feeding element and the fourth feeding element are all substantially equal.

In some embodiments, the first feed-in part includes a first narrower portion and a first wider portion, the first feed-in port is coupled to a first connection point on the first radiating part via the first narrower portion and the first wider portion, the second feed-in part includes a second narrower portion and a second wider portion, the second feed-in port is coupled to a second connection point on the first radiating part via the second narrower portion and the second wider portion, the third feed-in part includes a third narrower portion and a third wider portion, the third feed-in port is coupled to a third connection point on the first radiating part via the third narrower portion and the third wider portion, the fourth feed-in part includes a fourth narrower portion and a fourth wider portion, and the fourth feed-in port is coupled to a fourth connection point on the first radiating part via the fourth narrower portion and the fourth wider portion.

In some embodiments, the second wider portion and the first wider portion form a first included angle therebetween, the third wider portion and the second wider portion form a second included angle therebetween, and the fourth wider portion and the third wider portion form a third included angle therebetween.

In some embodiments, the first feeding element is coupled to a first connection point on the first radiation element, the second feeding element is coupled to a second connection point on the first radiation element, the third feeding element is coupled to a third connection point on the first radiation element, the fourth feeding element is coupled to a fourth connection point on the first radiation element, a first included angle is defined between the second connection point and the first connection point, a second included angle is defined between the third connection point and the second connection point, and a third included angle is defined between the fourth connection point and the third connection point, wherein the first included angle, the second included angle, and the third included angle are substantially equal to 45 degrees.

In some embodiments, the antenna structure further comprises: a first conductive through-element coupled between the first feeding-in part and a first connection point on the first radiation part; a second conductive through element coupled between the second feeding portion and a second connection point on the first radiating portion; a third conductive through element coupled between the third feeding part and a third connection point on the first radiating part; and a fourth conductive through element coupled between the fourth feeding part and a fourth connection point on the first radiating part.

In some embodiments, the first conductive through via member, the second conductive through via member, the third conductive through via member, and the fourth conductive through via member all at least partially penetrate the dielectric substrate.

In some embodiments, the first feeding element, the second feeding element, the third feeding element, and the fourth feeding element are all disposed between the first radiating element and the grounding element.

In some embodiments, the antenna structure operates in a first mode or a second mode to provide different polarization directions.

In some embodiments, in the first mode, the first feed-in port and the third feed-in port are enabled, the second feed-in port and the fourth feed-in port are disabled, and a first feed-in phase difference exists between the first feed-in port and the third feed-in port.

In some embodiments, in the second mode, the second feeding port and the fourth feeding port are enabled, the first feeding port and the third feeding port are disabled, and a second feeding phase difference exists between the second feeding port and the fourth feeding port.

Drawings

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

fig. 2 is a perspective view of an antenna structure according to an embodiment of the present invention;

fig. 3 is a cross-sectional view of an antenna structure according to an embodiment of the invention;

fig. 4 is a perspective view of an antenna structure according to an embodiment of the present invention;

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

fig. 6 is a perspective view of an antenna structure according to an embodiment of the invention;

fig. 7 is a side view of an antenna structure according to an embodiment of the invention.

Description of the symbols

100,400,500,600 antenna structure

110 ground element

120,420,520 first radiation part

130 second radiation part

140,640 dielectric substrate

150,650 first feeding part

151 first end of first feed-in part

152 the second end of the first feed-in part

154 first narrower portion

155 first wider portion

160,660 second feeding-in part

161 first end of the second feed-in part

162 second end of the second feed-in part

164 second narrower portion

165 second wider portion

170,670 the third feeding-in part

171 first end of third feed-in part

172 second end of the third feed-in part

174 third narrower portion

175 third wider portion

180,680 the fourth feeding-in part

181 first end of the fourth feeding-in part

182 the second end of the fourth feed-in part

184 fourth narrower part

185 fourth wider portion

521 the first gap

522 second gap

523 third gap

524 fourth gap

641 upper layer of dielectric substrate

642 intermediate layer of dielectric substrate

643 lower layer of dielectric substrate

691 first conductive via member

692 second conductive through member

693 third conductive through element

694 fourth conductive via

CC round mandrel

CP1 first connection Point

CP2 second connection Point

CP3 third connection Point

CP4 fourth connection Point

E1 first surface of dielectric substrate

E2 second surface of dielectric substrate

FP1 first feed-in port

FP2 second feed-in port

FP3 third feed-in port

FP4 fourth feed-in port

GC1 coupling gap

H1 thickness of dielectric substrate

LC1: section line

R1, R2 are radii

Theta 1 first angle

Theta 2 second angle

Third angle of theta 3

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.

The following disclosure provides many different embodiments, or examples, for implementing different features of the disclosure. The following disclosure describes specific examples of components and arrangements thereof to simplify the description. Of course, these specific examples are not intended to be limiting. For example, if the disclosure recites a first feature formed on or above a second feature, that embodiment may include that the first feature is in direct contact with the second feature, embodiments may include that additional features are formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the same reference signs or (and) labels may be repeated for different examples of the disclosure below. These iterations are for simplicity and clarity and are not intended to limit the particular relationship between the various embodiments or (and) structures discussed.

Furthermore, it is used in terms of spatial correlation. For example, in the illustrations below 823058, below, lower, above, upper and the like, to facilitate description of the relationship of one element or feature to another element or feature. These spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The device may be oriented in different orientations (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Fig. 1 shows a perspective view of an Antenna structure (Antenna System) 100 according to an embodiment of the invention. For example, the antenna structure 100 can be applied to a Wireless Access Point (Wireless Access Point), but is not limited thereto. As shown in fig. 1, the antenna structure 100 includes a Ground Element (Ground Element) 110, a first radiating Element (radiating Element) 120, a second radiating Element 130, a Dielectric Substrate (Dielectric Substrate) 140, a first Feeding Element (Feeding Element) 150, a second Feeding Element 160, a third Feeding Element 170, and a fourth Feeding Element 180, wherein the Ground Element 110, the first radiating Element 120, the second radiating Element 130, the first Feeding Element 150, the second Feeding Element 160, the third Feeding Element 170, and the fourth Feeding Element 180 may be made of metal materials, for example: copper, silver, aluminum, iron, or alloys thereof. Fig. 2 shows a perspective view of the antenna structure 100 according to an embodiment of the invention (the ground element 110 and the dielectric substrate 140 are omitted for simplicity of illustration). Fig. 3 shows a cross-sectional view (along a section line LC1 of fig. 1) of the antenna structure 100 according to an embodiment of the invention. Please refer to fig. 1, fig. 2, and fig. 3 together to understand the present invention.

The Ground element 110 provides a Ground Voltage (Ground Voltage). The first radiating portion 120 may generally exhibit a circular shape. The dielectric substrate 140 may be an FR4 (film resistor 4) substrate, a Printed Circuit Board (PCB), or a Flexible Printed Circuit Board (FPC). The dielectric substrate 140 has a first surface E1 and a second surface E2 opposite to each other, wherein the first radiating portion 120 is disposed on the first surface E1 of the dielectric substrate 140, and the grounding element 110 is disposed on the second surface E2 of the dielectric substrate 140. The area of the ground element 110 may be much larger than that of the first radiation part 120.

The second radiation part 130 may exhibit another circle (a larger circle), wherein the area of the second radiation part 130 may be larger than the area of the first radiation part 120. The second radiation portion 130 and the first radiation portion 120 may share the same circular mandrel CC, which may be substantially perpendicular to the first surface E1 of the dielectric substrate 140. That is, the center of the second radiation portion 130 may overlap the center of the first radiation portion 120, wherein the circular center axis CC may pass through the two centers at the same time. The second radiation part 130 is adjacent to the first radiation part 120 and is completely separated from the first radiation part 120. In other words, the second radiation portion 130 may exhibit a Floating state (Floating). It should be noted that the term "adjacent" or "neighboring" in this specification may refer to the pitch of corresponding elements being smaller than a predetermined distance (e.g., 5mm or less), but generally does not include the case where corresponding elements are in direct contact with each other (i.e., the pitch is shortened to 0). In some embodiments, the second radiation part 130 is substantially parallel to the first radiation part 120, wherein a Coupling Gap (Coupling Gap) GC1 may be formed between the second radiation part 130 and the first radiation part 120. In addition, if the second radiation part 130 has a Vertical Projection (Vertical Projection) on the first surface E1 of the dielectric substrate 140, the first radiation part 120 is located completely inside the Vertical Projection of the second radiation part 130.

The first feeding element 150, the second feeding element 160, the third feeding element 170, and the fourth feeding element 180 may be disposed on the first surface E1 of the dielectric substrate 140, and they may be Coplanar (Coplanar) with the first radiation element 120. For example, each of the first feeding element 150, the second feeding element 160, the third feeding element 170, and the fourth feeding element 180 may substantially have a zigzag Shape, a straight strip Shape, or a Meandering Shape (meaningshape), but is not limited thereto.

The first Feeding element 150 has a first end 151 and a second end 152, wherein a first Feeding Port (Feeding Port) FP1 is located at the first end 151 of the first Feeding element 150, and the second end 152 of the first Feeding element 150 is coupled to a first Connection Point (Connection Point) CP1 on the first radiation element 120. The second feeding element 160 has a first end 161 and a second end 162, wherein a second feeding port FP2 is located at the first end 161 of the second feeding element 160, and the second end 162 of the second feeding element 160 is coupled to a second connection point CP2 on the first radiating element 120. The third feeding element 170 has a first end 171 and a second end 172, wherein a third feeding port FP3 is located at the first end 171 of the third feeding element 170, and the second end 172 of the third feeding element 170 is coupled to a third connection point CP3 on the first radiating element 120. The fourth feeding element 180 has a first end 181 and a second end 182, wherein a fourth feeding port FP4 is located at the first end 181 of the fourth feeding element 180, and the second end 182 of the fourth feeding element 180 is coupled to a fourth connection point CP4 on the first radiating element 120. The aforementioned first connection point CP1, second connection point CP2, third connection point CP3, and fourth connection point CP4 may be different from each other, and they may be located on the circumference of the first radiation part 120. In some embodiments, the lengths of the first feeding element 150, the second feeding element 160, the third feeding element 170, and the fourth feeding element 180 are substantially equal to provide substantially the same Phase Delay (Phase Delay).

In some embodiments, the first feeding part 150, the second feeding part 160, the third feeding part 170, and the fourth feeding part 180 are all in a Variable-Width Structure (Variable-Width Structure). In detail, the first feeding unit 150 includes a first Narrow Portion (Narrow Portion) 154 and a first Wide Portion (Wide Portion) 155, wherein the first feeding port FP1 is coupled to the first connection point CP1 via the first Narrow Portion 154 and the first Wide Portion 155. The second feeding part 160 includes a second narrow portion 164 and a second wide portion 165, wherein the second feeding port FP2 is coupled to the second connection point CP2 via the second narrow portion 164 and the second wide portion 165. The third feeding part 170 includes a third narrow portion 174 and a third wide portion 175, wherein the third feeding port FP3 is coupled to the third connection point CP3 via the third narrow portion 174 and the third wide portion 175. The fourth feeding part 180 includes a fourth narrower portion 184 and a fourth wider portion 185, wherein the fourth feeding port FP4 is coupled to the fourth connection point CP4 via the fourth narrower portion 184 and the fourth wider portion 185. Such a design with different widths can be used to fine-tune the Feeding Impedance (Feeding Impedance) of the antenna structure 100 according to actual measurement results. However, the present invention is not limited thereto. In other embodiments, the first feeding part 150, the second feeding part 160, the third feeding part 170, and the fourth feeding part 180 may be changed to have an Equal-Width Structure (Equal-Width Structure). In still other embodiments, the first feeding element 150, the second feeding element 160, the third feeding element 170, and the fourth feeding element 180 may be a multi-segment structure (e.g., more than two segments, wherein each segment is not parallel to each other), or a structure with gradually changing width.

A first included angle θ 1 may be formed between the second wider portion 165 of the second feeding part 160 and the first wider portion 155 of the first feeding part 150. A second included angle θ 2 may be formed between the third wide portion 175 of the third feeding part 170 and the second wide portion 165 of the second feeding part 160. A third included angle θ 3 may be formed between the fourth wide portion 185 of the fourth feeding part 180 and the third wide portion 175 of the third feeding part 170. For example, extensions of each of the aforementioned first wider portion 155, second wider portion 165, third wider portion 175, and fourth wider portion 185 may pass through the circular mandrel CC. In some embodiments, the first included angle θ 1, the second included angle θ 2, and the third included angle θ 3 are substantially equal to each other. In other embodiments, first included angle θ 1 is defined between second connection point CP2 and first connection point CP1, second included angle θ 2 is defined between third connection point CP3 and second connection point CP2, and third included angle θ 3 is defined between fourth connection point CP4 and third connection point CP3. For example, any two adjacent connection points are respectively connected to the circular mandrel CC, so that two sides of the corresponding included angle can be defined, but the invention is not limited thereto.

In some embodiments, the antenna structure 100 may cover an operating Frequency Band (Operational Frequency Band) between 2400MHz and 2500MHz, and the principles thereof may be as follows. Feeding Energy (Feeding Energy) from a Signal Source (not shown) can enter from any two of the first Feeding port FP1, the second Feeding port FP2, the third Feeding port FP3, and the fourth Feeding port FP4 to excite the antenna structure 100. The second Radiation portion 130 can be coupled and excited by the first Radiation portion 120 to enhance a Radiation Pattern (Radiation Pattern) of the antenna structure 100. With this design, the antenna structure 100 will support at least 2.4GHz wide band WLAN (Wireless Local Area Network) operation.

In some embodiments, the antenna structure 100 may operate in either a first mode or a second mode to provide different Polarization (Polarization) directions. In the first mode, the first Feeding port FP1 and the third Feeding port FP3 are both Enabled (Enabled or in use), and the second Feeding port FP2 and the fourth Feeding port FP4 are Disabled (Disabled or not in use), wherein a first Feeding Phase Difference (Feeding Phase Difference) may exist between the first Feeding port FP1 and the third Feeding port FP 3. In the second mode, the second feed port FP2 and the fourth feed port FP4 are both enabled, and the first feed port FP1 and the third feed port FP3 are both disabled, wherein a second feed phase difference exists between the second feed port FP2 and the fourth feed port FP 4. For example, the first feeding phase difference and the second feeding phase difference may be respectively equal to 0 degree, 45 degrees, 90 degrees, 135 degrees, or 180 degrees, but not limited thereto. By selecting appropriate feed ports and adjusting the feed phase difference therebetween, the antenna structure 100 can provide various polarization directions.

In some embodiments, the element dimensions of the antenna structure 100 may be as follows. The radius R1 of the first radiation portion 120 may be substantially equal to 0.25 times the guiding wavelength (i.e., λ g/4, wherein the guiding wavelength λ g is defined in the dielectric substrate 140 and is adjusted according to the dielectric constant of the dielectric substrate 140) of the operating band of the antenna structure 100. The radius R2 of the second radiating portion 130 may be substantially equal to 0.25 times the free-space wavelength (i.e., λ f/4, where "free-space wavelength λ f" is defined in free space) of the operating frequency band of the antenna structure 100. For example, the radius R2 of the second radiation portion 130 may be approximately 2 times the radius R1 of the first radiation portion 120. The width of the coupling gap GC1 between the second radiation part 130 and the first radiation part 120 may be substantially equal to 0.05 times the free-space wavelength (λ f/20) of the operation band of the antenna structure 100. The thickness H1 of the dielectric substrate 140 may be between 0.4mm and 1.6 mm. The Dielectric Constant (Dielectric Constant) of the Dielectric substrate 140 may be between 2 and 16. A first included angle θ 1 between the second wider portion 165 of the second feeding part 160 and the first wider portion 155 of the first feeding part 150 may be substantially equal to 45 degrees. A second included angle θ 2 between the third wide portion 175 of the third feeding part 170 and the second wide portion 165 of the second feeding part 160 may be substantially equal to 45 degrees. A third included angle θ 3 between the fourth wide portion 185 of the fourth feeding part 180 and the third wide portion 175 of the third feeding part 170 may be substantially equal to 45 degrees. The above range of element sizes is derived from a number of experimental results, which help to optimize the Tunable Polarization (Tunable Polarization), the operating Bandwidth (Operational Bandwidth), and the Impedance Matching (Impedance Matching) of the antenna structure 100.

Fig. 4 shows a perspective view of an antenna structure 400 according to an embodiment of the invention (the ground element 110 and the dielectric substrate 140 are omitted for simplicity of illustration). Fig. 4 is similar to fig. 2. In the embodiment of fig. 4, a first radiating portion 420 of the antenna structure 400 is substantially in the shape of a regular octagon. In other embodiments, the first radiation portion 420 may be a regular N-polygon, where N may be a multiple of 8, or may be any integer greater than or equal to 16. Different shapes of the first radiating portion 420 may be used to fine tune the impedance matching of the antenna structure 400, depending on actual measurements. The remaining features of the antenna structure 400 of fig. 4 are similar to those of the antenna structure 100 of fig. 1, 2, and 3, so that similar operation effects can be achieved in both embodiments.

Fig. 5 shows a perspective view of an antenna structure 500 according to an embodiment of the invention (the ground element 110 and the dielectric substrate 140 are omitted for simplicity of illustration). Fig. 5 is similar to fig. 2. In the embodiment of fig. 5, a first radiation portion 520 of the antenna structure 500 further has a first Notch (Notch) 521, a second Notch 522, a third Notch 523, and a fourth Notch 524, which correspond to the first feeding portion 150, the second feeding portion 160, the third feeding portion 170, and the fourth feeding portion 180, respectively. For example, each of the first notch 521, the second notch 522, the third notch 523, and the fourth notch 524 may substantially present a triangle shape, but is not limited thereto. The addition of the first gap 521, the second gap 522, the third gap 523, and the fourth gap 524 may be used to fine tune the impedance matching of the antenna structure 500 according to actual measurement results. The remaining features of the antenna structure 500 of fig. 5 are similar to those of the antenna structure 100 of fig. 1, 2, and 3, so that similar operation effects can be achieved in both embodiments.

Fig. 6 is a perspective view of an antenna structure 600 according to an embodiment of the invention. Fig. 7 shows a side view of an antenna structure 600 according to an embodiment of the invention. Fig. 6 and 7 are similar to fig. 1 and 3. In the embodiments of fig. 6 and 7, a dielectric substrate 640 of the antenna structure 600 is a three-layer circuit board and has an upper layer 641, an intermediate layer 642 and a lower layer 643, and the antenna structure 600 further includes a first Conductive Via Element (Conductive Via Element) 691, a second Conductive Via Element 692, a third Conductive Via Element 693 and a fourth Conductive Via Element 694. The first, second, third, and fourth conductive through- members 691, 692, 693, and 694 all penetrate at least partially through the dielectric substrate 640. In addition, a first feeding element 650, a second feeding element 660, a third feeding element 670, and a fourth feeding element 680 of the antenna structure 600 are disposed in the middle layer 642 of the dielectric substrate 640, and may be disposed between the first radiating element 120 and the ground element 110. The first conductive through via 691 is coupled between the first feeding portion 650 and the first connection point CP1 on the first radiating portion 120. The second conductive through-element 692 is coupled between the second feeding portion 660 and the second connection point CP2 on the first radiation portion 120. The third conductive through member 693 is coupled between the third feeding part 670 and a third connection point CP3 on the first radiation part 120. The fourth conductive through element 694 is coupled between the fourth feeding part 680 and a fourth connection point CP4 on the first radiating part 120. This design of embedding all the feeding portions and the conductive vias in the dielectric substrate 640 can increase the integration and manufacturing flexibility of the antenna structure 600. The remaining features of the antenna structure 600 of fig. 6 and 7 are similar to those of the antenna structure 100 of fig. 1, 2 and 3, so that similar operation effects can be achieved in both embodiments.

The present invention provides a novel antenna structure. Compared with the prior art, the invention has the advantages of multi-polarization, small size, wide frequency band, low manufacturing cost and the like, so the invention is very suitable for being applied to various 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 7. The present invention may include only any one or more features of any one or more of the embodiments of fig. 1-7. 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 to be used in a sequential order, but merely to distinguish between 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 (20)

1. An antenna structure comprising:

a ground element;

a first radiation section;

a dielectric substrate having a first surface and a second surface opposite to each other, wherein the first radiating portion is disposed on the first surface, and the grounding element is disposed on the second surface;

a second radiation part adjacent to the first radiation part and separated from the first radiation part;

a first feed-in part having a first feed-in port and coupled to the first radiation part;

a second feeding part having a second feeding port and coupled to the first radiation part;

a third feeding part having a third feeding port and coupled to the first radiation part; and

a fourth feeding part having a fourth feeding port and coupled to the first radiation part;

wherein the antenna structure covers an operating frequency band.

2. The antenna structure of claim 1 wherein the operating band is between 2400MHz and 2500 MHz.

3. The antenna structure of claim 1, wherein the first radiating portion exhibits a circular shape.

4. The antenna structure of claim 3, wherein the radius of the first radiating portion is approximately equal to 0.25 guide wavelengths of the operating band.

5. The antenna structure of claim 1, wherein the first radiating portion exhibits a regular octagon shape.

6. The antenna structure according to claim 1, wherein the first radiating portion further has a first notch, a second notch, a third notch and a fourth notch, which correspond to the first feeding portion, the second feeding portion, the third feeding portion and the fourth feeding portion, respectively.

7. The antenna structure of claim 1, wherein the second radiating portion has another circular shape, and the area of the second radiating portion is larger than the area of the first radiating portion.

8. The antenna structure of claim 7, wherein the radius of the second radiating portion is approximately equal to 0.25 free-space wavelengths of the operating band.

9. The antenna structure of claim 1, wherein the second radiating portion is substantially parallel to the first radiating portion, and a coupling gap is formed between the second radiating portion and the first radiating portion.

10. The antenna structure of claim 9 wherein the width of the coupling gap is approximately equal to 0.05 free-space wavelengths of the operating band.

11. The antenna structure according to claim 1, wherein the lengths of the first feeding element, the second feeding element, the third feeding element and the fourth feeding element are substantially equal.

12. The antenna structure according to claim 1, wherein the first feed-in part comprises a first narrow portion and a first wide portion, the first feed-in port is coupled to a first connection point on the first radiating part via the first narrow portion and the first wide portion, the second feed-in part comprises a second narrow portion and a second wide portion, the second feed-in port is coupled to a second connection point on the first radiating part via the second narrow portion and the second wide portion, the third feed-in part comprises a third narrow portion and a third wide portion, the third feed-in port is coupled to a third connection point on the first radiating part via the third narrow portion and the third wide portion, the fourth feed-in part comprises a fourth narrow portion and a fourth wide portion, and the fourth feed-in port is coupled to a fourth connection point on the first radiating part via the fourth narrow portion and the fourth wide portion.

13. The antenna structure of claim 12 wherein the second wider portion and the first wider portion form a first angle therebetween, the third wider portion and the second wider portion form a second angle therebetween, and the fourth wider portion and the third wider portion form a third angle therebetween.

14. The antenna structure according to claim 1, wherein the first feeding element is coupled to a first connection point on the first radiating element, the second feeding element is coupled to a second connection point on the first radiating element, the third feeding element is coupled to a third connection point on the first radiating element, the fourth feeding element is coupled to a fourth connection point on the first radiating element, a first included angle is defined between the second connection point and the first connection point, a second included angle is defined between the third connection point and the second connection point, and a third included angle is defined between the fourth connection point and the third connection point, wherein the first included angle, the second included angle, and the third included angle are substantially equal to 45 degrees.

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

a first conductive through element coupled between the first feeding part and a first connection point on the first radiation part;

a second conductive through element coupled between the second feeding part and a second connection point on the first radiating part;

a third conductive through element coupled between the third feeding part and a third connection point on the first radiating part; and

and the fourth conductive through element is coupled between the fourth feed-in part and a fourth connection point on the first radiation part.

16. The antenna structure of claim 15, wherein the first conductive via element, the second conductive via element, the third conductive via element, and the fourth conductive via element all at least partially penetrate the dielectric substrate.

17. The antenna structure according to claim 15, wherein the first feeding element, the second feeding element, the third feeding element and the fourth feeding element are disposed between the first radiating element and the ground element.

18. The antenna structure of claim 1 wherein the antenna structure operates in a first mode or a second mode to provide different polarization directions.

19. The antenna structure of claim 18, wherein in the first mode, the first feeding port and the third feeding port are enabled, the second feeding port and the fourth feeding port are disabled, and there is a first feeding phase difference between the first feeding port and the third feeding port.

20. The antenna structure of claim 18, wherein in the second mode, the second feeding port and the fourth feeding port are enabled, the first feeding port and the third feeding port are disabled, and a second feeding phase difference exists between the second feeding port and the fourth feeding port.

Images