Patent Grant
12206181
This application claims priority of Taiwan Patent Application No. 111117561 filed on May 11, 2022, the entirety of which is incorporated by reference herein.
The disclosure generally relates to an antenna system, and more particularly, to an antenna system with a switchable radiation pattern.
With the advancements being made in mobile communication technology, mobile devices such as portable computers, mobile phones, multimedia players, and other hybrid functional portable electronic devices have become more common. To satisfy consumer demand, mobile devices can usually perform wireless communication functions. Some devices cover a large wireless communication area; these include mobile phones using 2G, 3G, and LTE (Long Term Evolution) systems and using frequency bands of 700 MHz, 850 MHz, 900 MHz, 1800 MHz, 1900 MHz, 2100 MHz, 2300 MHz, and 2500 MHz. Some devices cover a small wireless communication area; these include mobile phones using Wi-Fi systems and using frequency bands of 2.4 GHz, 5.2 GHz, and 5.8 GHz.
Wireless access points are indispensable elements for mobile devices in a room to connect to the Internet at a high speed. However, since an indoor environment can experience serious signal reflection and multipath fading, wireless access points should process signals from a variety of transmission directions simultaneously. Accordingly, it has become a critical challenge for current designers to design a small-size and omnidirectional antenna system in the limited space of a wireless access point.
In an exemplary embodiment, the invention is directed to an antenna system that includes a signal feeding element, a first antenna element, a second antenna element, a first selection circuit, a second selection circuit, a first transmission line, a second transmission line, a third transmission line, a fourth transmission line, a fifth transmission line, and a sixth transmission line. The feeding element is respectively coupled to a first connection point and a second connection point. The first antenna element is coupled to a third connection point. The second antenna element is coupled to a fourth connection point. The first selection circuit selects one of the first transmission line, the second transmission line, and the third transmission line as a first target transmission line. The selected first target transmission line is coupled between the third connection point and the first connection point. The second selection circuit selects one of the fourth transmission line, the fifth transmission line, and the sixth transmission line as a second target transmission line. The selected second target transmission line is coupled between the fourth connection point and the second connection point.
The invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:
In order to illustrate the purposes, features and advantages of the invention, the embodiments and figures of the invention are shown in detail as follows.
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. This document does 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” means the value is within an acceptable error range. One skilled in the art can solve the technical problem within a predetermined error range and achieve the proposed technical performance. Also, the term “couple” is intended to mean either an indirect or direct electrical connection. Accordingly, if one device is coupled to another 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 provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
Furthermore, spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The 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 apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly.
The signal feeding element 110 may be implemented with one or more feeding metal elements. For example, the signal feeding element 110 may be coupled to an RF (Radio Frequency) module (not shown) for exciting the antenna system 100. The signal feeding element 110 is respectively coupled to a first connection point FP1 and a second connection point FP2. The shapes and types of the first antenna element 121 and the second antenna element 122 are not limited in the invention. For example, each of the first antenna element 121 and the second antenna element 122 may be a monopole antenna, a dipole antenna, a patch antenna, a loop antenna, a PIFA (Planar Inverted F Antenna), or a hybrid antenna. The first antenna element 121 is coupled to a third connection point FP3. The second antenna element 122 is coupled to a fourth connection point FP4.
The shapes and types of the first transmission line 151, the second transmission line 152, the third transmission line 153, the fourth transmission line 154, the fifth transmission line 155, and the sixth transmission line 156 are not limited in the invention. The first transmission line 151, the second transmission line 152, the third transmission line 153, the fourth transmission line 154, the fifth transmission line 155, and the sixth transmission line 156 may have the same lengths or different lengths. For example, if the first transmission line 151, the second transmission line 152, and the third transmission line 153 have the same lengths, the fourth transmission line 154, the fifth transmission line 155, and the sixth transmission line 156 will have different lengths. Alternatively, if the fourth transmission line 154, the fifth transmission line 155, and the sixth transmission line 156 have the same lengths, the first transmission line 151, the second transmission line 152, and the third transmission line 153 will have different lengths. In some embodiments, the length of the fourth transmission line 154 is longer than or equal to the length of the first transmission line 151, the length of the fifth transmission line 155 is substantially equal to the length of the second transmission line 152, and the length of the sixth transmission line 156 is shorter than or equal to the length of the third transmission line 153.
The first selection circuit 130 may select one of the first transmission line 151, the second transmission line 152, and the third transmission line 153 as a first target transmission line. The selected first target transmission line is coupled between the third connection point FP3 and the first connection point FP1. Furthermore, the second selection circuit 140 may select one of the fourth transmission line 154, the fifth transmission line 155, and the sixth transmission line 156 as a second target transmission line. The selected second target transmission line is coupled between the fourth connection point FP4 and the second connection point FP2. For example, the first selection circuit 130 and the second selection circuit 140 may perform the aforementioned selection processes according to a user input or a control signal of a processor. It should be noted that the first transmission line 151, the second transmission line 152, the third transmission line 153, the fourth transmission line 154, the fifth transmission line 155, and the sixth transmission line 156 are configured to provide the same feeding phases or different feeding phases. For example, if the first transmission line 151, the second transmission line 152, and the third transmission line 153 provide the same feeding phases, the fourth transmission line 154, the fifth transmission line 155, and the sixth transmission line 156 will provide different feeding phases. Alternatively, if the fourth transmission line 154, the fifth transmission line 155, and the sixth transmission line 156 provide the same feeding phases, the first transmission line 151, the second transmission line 152, and the third transmission line 153 will provide different feeding phases. According to practical measurements, the antenna system 100 of the invention can provide an almost omnidirectional radiation pattern by using the first selection circuit 130 and the second selection circuit 140.
The following embodiments will introduce different configurations and detailed structural features of the antenna system 100. It should be understood that these figures and descriptions are merely exemplary, rather than limitations of the invention.
The length of the second feeding line 162 may be substantially equal to the length of the first feeding line 161. The first feeding line 161 is coupled between the first connection point FP1 and the signal feeding element 110. The second feeding line 162 is coupled between the second connection point FP2 and the signal feeding element 110. In some embodiments, each of the first feeding line 161 and the second feeding line 162 substantially have a variable-width straight-line shape for impedance matching adjustments, but it is not limited thereto. The third antenna element 123 is coupled to the first connection point FP1. The fourth antenna element 124 is coupled to the second connection point FP2.
The first selection circuit 130 includes a first switch element 134 and a second switch element 135. Each of the first switch element 134 and the second switch element 135 may be an SP3T (Single Port Three Throw) switch element. Specifically, the first switch element 134 and the second switch element 135 are configured to select one of the first transmission line 151, the second transmission line 152, and the third transmission line 153 as the first target transmission line coupled between the third connection point FP3 and the first connection point FP1.
The second selection circuit 140 includes a third switch element 144 and a fourth switch element 145. Each of the third switch element 144 and the fourth switch element 145 may be an SP3T switch element. Specifically, the third switch element 144 and the fourth switch element 145 are configured to select one of the fourth transmission line 154, the fifth transmission line 155, and the sixth transmission line 156 as the second target transmission line coupled between the fourth connection point FP4 and the second connection point FP2.
The fifth antenna element 125 is coupled to a fifth connection point FP5. The third selection circuit 170 may select one of the seventh transmission line 191, the eighth transmission line 192, and the ninth transmission line 193 as a third target transmission line. The selected third target transmission line is coupled between the fifth connection point FP5 and the third connection point FP3. Specifically, the third selection circuit 170 includes a fifth switch element 174 and a sixth switch element 175. Each of the fifth switch element 174 and the sixth switch element 175 may be an SP3T switch element. For example, the length of the tenth transmission line 194 may be longer than or equal to the length of the fourth transmission line 154, the length of the fourth transmission line 154 may be longer than or equal to the length of the first transmission line 151, and the length of the first transmission line 151 may be longer than or equal to the length of the seventh transmission line 191, but they are not limited thereto. In addition, the second transmission line 152, the fifth transmission line 155, the eighth transmission line 192, and the eleventh transmission line 195 may substantially have the same lengths.
The sixth antenna element 126 is coupled to a sixth connection point FP6. The fourth selection circuit 180 may select one of the tenth transmission line 194, the eleventh transmission line 195, and the twelfth transmission line 196 as a fourth target transmission line. The selected fourth target transmission line is coupled between the sixth connection point FP6 and the fourth connection point FP4. Specifically, the fourth selection circuit 180 includes a seventh switch element 184 and an eighth switch element 185. Each of the seventh switch element 184 and the eighth switch element 185 may be an SP3T switch element. For example, the length of the twelfth transmission line 196 may be shorter than or equal to the length of the sixth transmission line 156, the length of the sixth transmission line 156 may be shorter than or equal to the length of the third transmission line 153, and the length of the third transmission line 153 may be shorter than or equal to the length of the ninth transmission line 193, but they are not limited thereto.
It should be understood that in response to a variety of use requirements, the antenna system 200 may further include more antenna elements, more selection circuits, and more transmission lines. Other features of the antenna system 200 of
Each of the first antenna element 321, the second antenna element 322, the third antenna element 323, the fourth antenna element 324, the fifth antenna element 325, the sixth antenna element 326, the seventh antenna element 421, the eighth antenna element 422, the ninth antenna element 423, the tenth antenna element 424, the eleventh antenna element 425, and the twelfth antenna element 426 may be implemented with a dipole antenna. The above antenna elements may be distributed over a top surface and a bottom surface of a dielectric substrate (in order to simplify the figure, the dielectric substrate is not displayed in
The first selection circuit 330 includes a first switch element 334 and a second switch element 335, and it is switchable between the first transmission line 351, the second transmission line 352, and the third transmission line 353, so as to select a first target transmission line. The second selection circuit 340 includes a third switch element 344 and a fourth switch element 345, and it is switchable between the fourth transmission line 354, the fifth transmission line 355, and the sixth transmission line 356, so as to select a second target transmission line. The third selection circuit 370 includes a fifth switch element 374 and a sixth switch element 375, and it is switchable between the seventh transmission line 391, the eighth transmission line 392, and the ninth transmission line 393, so as to select a third target transmission line. The fourth selection circuit 380 includes a seventh switch element 384 and an eighth switch element 385, and it is switchable between the tenth transmission line 394, the eleventh transmission line 395, and the twelfth transmission line 396, so as to select a fourth target transmission line.
In some embodiments, the antenna system 300 operates in either a first mode, a second mode, or a third mode. In the first mode, the first transmission line 351, the fourth transmission line 354, the seventh transmission line 391, and the tenth transmission line 394 are selected as the first target transmission line, the second target transmission line, the third target transmission line, and the fourth target transmission line, respectively. In the second mode, the second transmission line 352, the fifth transmission line 355, the eighth transmission line 392, and the eleventh transmission line 395 are selected as the first target transmission line, the second target transmission line, the third target transmission line, and the fourth target transmission line, respectively. Furthermore, in the third mode, the third transmission line 353, the sixth transmission line 356, the ninth transmission line 393, and the twelfth transmission line 396 are selected as the first target transmission line, the second target transmission line, the third target transmission line, and the fourth target transmission line, respectively.
In some embodiments, the element sizes of the antenna system 300 will be described as follows. The first transmission line 351, the sixth transmission line 356, the seventh transmission line 391, and the twelfth transmission line 396 may have the same lengths, which may be from 0.25 to 0.31 wavelength (0.25λ-0.31λ) of the operational frequency band of the antenna system 300. The third transmission line 353, the fourth transmission line 354, the ninth transmission line 393, and the tenth transmission line 394 may have the same lengths, which may be from 0.69 to 0.85 wavelength (0.69λ-0.85λ) of the operational frequency band of the antenna system 300. The second transmission line 352, the fifth transmission line 355, the eighth transmission line 392, and the eleventh transmission line 395 may have the same lengths, which may be from 0.16 to 0.19 wavelength (0.16λ-0.19λ) of the operational frequency band of the antenna system 300. The distance D1 between the third antenna element 323 and the fourth antenna element 324 may be from 0.24 to 0.3 wavelength (0.24λ-0.3λ) of the operational frequency band of the antenna system 300. The distance D2 between the fifth antenna element 325 and the first antenna element 321 may be from 0.04 to 0.06 wavelength (0.04λ-0.06λ) of the operational frequency band of the antenna system 300. The first angle θ1 may be from 10 to 20 degrees, such as about 15 degrees. The second angle θ2 may be from 10 to 20 degrees, such as about 15 degrees. The above ranges of element sizes are calculated and obtained according to many experiment results, and they help to optimize the operational bandwidth and the impedance matching of the antenna system 300. Other features of the antenna system 300 of
Each of the first antenna element 521 and the second antenna element 522 may be a square patch antenna. In addition, each of the first floating metal element 598 and the second floating metal element 599 may substantially have a circular shape, and they are completely separate from the first antenna element 521 and the second antenna element 522. Specifically, the first floating metal element 598 is adjacent to the first antenna element 521, so as to increase the radiation gain of the first antenna element 521, and the second floating metal element 599 is adjacent to the second antenna element 522, so as to increase the radiation gain of the second antenna element 522. It should be noted that the term “adjacent” or “close” over the disclosure means that the distance (spacing) between two corresponding elements is smaller than a predetermined distance (e.g., 10 mm or shorter), but often does not mean that the two corresponding elements directly touch each other (i.e., the aforementioned distance/spacing therebetween is reduced to 0).
The invention proposes a novel antenna system. In comparison to the conventional design, the invention has at least the advantages of switchable radiation pattern, small size, and low manufacturing cost. Therefore, the invention is suitable for application in a variety of communication devices.
Note that the above element sizes, element shapes, and frequency ranges are not limitations of the invention. An antenna designer can fine-tune these settings or values according to different requirements. It should be understood that the antenna system of the invention is not limited to the configurations of
Use of ordinal terms such as “first”, “second”, “third”, etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having the same name (but for use of the ordinal term) to distinguish the claim elements.
While the invention has been described by way of example and in terms of the preferred embodiments, it should be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
| Number | Date | Country | Kind |
|---|---|---|---|
| 111117561 | May 2022 | TW | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 20050110683 | Song | May 2005 | A1 |
| 20130093634 | Rowson | Apr 2013 | A1 |
| 20130335290 | Desclos et al. | Dec 2013 | A1 |
| 20150155621 | Desclos | Jun 2015 | A1 |
| Number | Date | Country |
|---|---|---|
| 200723600 | Jun 2007 | TW |
| Number | Date | Country | |
|---|---|---|---|
| 20230369759 A1 | Nov 2023 | US |
