Patent Application
20170352945
This Application claims priority of Taiwan Patent Application No. 105208204 filed on Jun. 1, 2016, the entirety of which is incorporated by reference herein.
The disclosure generally relates to a communication device, and more particularly, to a communication device and an antenna structure therein.
With advancements 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 and Bluetooth 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 the room to connect to the Internet at a high speed. However, since indoor environments have serious signal reflection and multipath fading, wireless access points should process signals from a variety of directions simultaneously. Accordingly, it has become a critical challenge for antenna designers to design an almost omnidirectional antenna structure in the limited space of wireless access points.
In a preferred embodiment, the disclosure is directed to a communication device including a system ground plane, a signal source, an antenna structure, a radiation adjustment plane, and a first tuning metal element. The signal source is coupled to the system ground plane. The antenna structure is coupled to the signal source. The radiation adjustment plane is configured to adjust the radiation of the antenna structure. The first tuning metal element is disposed adjacent to the antenna structure, and is configured to modify the radiation pattern of the antenna structure.
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 detailed structure and element arrangement of the communication device 100 will be described in the following embodiments and figures. It should be understood that these embodiments and figures are just exemplary, rather than limitations of the scope of the patent application.
In the embodiment of
The first tuning metal element 240 is float and adjacent to the antenna structure 220. The first tuning metal element 240 and the antenna structure 220 are completely separated from each other. The mutual coupling is induced between the first tuning metal element 240 and the antenna structure 220. The first tuning metal element 240 may substantially have an L-shape, a quarter-arc-shape (as shown in
With respect to antenna theory, the feeding radiation element 221 and the grounding radiation element 222 of the antenna structure 220 are both disposed parallel to the X-axis, and their resonant currents are also parallel to the X-axis, such that the radiation pattern of the antenna structure 220 has nulls in the +X-axis direction and the −X-axis direction. In order to arrange the antenna structure 220 toward the desired radiation pattern, the invention adds at least one of the first tuning metal element 240 and the second tuning metal element 250. With such a design, the mutual coupling is induced between the first tuning metal element 240 and the feeding radiation element 221 of the antenna structure 220, and the first coupling current flows through the second portion 242 of the first tuning metal element 240 and is parallel to the Y-axis. Similarly, the mutual coupling is induced between the second tuning metal element 250 and the grounding radiation element 222 of the antenna structure 220, and the second coupling current flows through the fourth portion 252 of the second tuning metal element 250 and is parallel to the Y-axis. Since the first coupling current of the first tuning metal element 240 and the second coupling current of the second tuning metal element 250 are both perpendicular to the direction of the resonant current of the antenna structure 220, these coupling currents can compensate for the pattern nulls of the antenna structure 220 in the +X-axis direction and the −X-axis direction. Accordingly, the communication device 200 has relatively uniform antenna gain in a variety of directions in which energy concentration is required.
In some embodiments, the operation frequency band of the antenna structure 220 is from 57 GHz to 66 GHz, and the related element sizes are as follows. The length L1 of the first portion 241 of the first tuning metal element 240 is from 1/9 to ⅓ wavelength (λ/9 to λ/3) of the operation frequency band, and is preferably ¼ wavelength (λ/4). The length L2 of the second portion 242 of the first tuning metal element 240 is about ½ wavelength (λ/2) of the operation frequency band. The length L3 of the third portion 251 of the second tuning metal element 250 is from 1/9 to ⅓ wavelength (λ/9 to λ/3) of the operation frequency band, and is preferably ¼ wavelength (λ/4). The length L4 of the fourth portion 252 of the second tuning metal element 250 is about ½ wavelength (λ/2) of the operation frequency band. Specifically, the length L1 and the length L3 are used to control the amount of mutual coupling between the antenna structure 220 and the corresponding tuning metal element, and the length L2 and the length L4 are used to control the resonant frequency of the corresponding tuning metal element. The distance D1 between the first portion 241 of the first tuning metal element 240 and the feeding radiation element 221 is from 1/20 to ⅓ wavelength (λ/20 to λ/3) of the operation frequency band, and is preferably ⅕ wavelength (λ/5). The distance D2 between the second portion 242 of the first tuning metal element 240 and the feeding radiation element 221 is from 1/20 to ½ wavelength (λ/20 to λ/2) of the operation frequency band, and is preferably ⅛ wavelength (λ/8). The distance D3 between the third portion 251 of the second tuning metal element 250 and the grounding radiation element 222 is from 1/20 to ⅓ wavelength (λ/20 to λ/3) of the operation frequency band, and is preferably ⅕ wavelength (λ/5). The distance D4 between the fourth portion 252 of the second tuning metal element 250 and the grounding radiation element 222 is from 1/20 to ½ wavelength (λ/20 to λ/2) of the operation frequency band, and is preferably ⅛ wavelength (λ/8). The above element sizes are calculated and obtained according to many simulation results, and they can optimize the antenna gain and radiation pattern of the communication device 200.
In the embodiment of
As to the element sizes, the length L5 of the radiation adjustment plane 330 is longer than or equal to the distance D5 between the antenna structure 320 and the system ground plane 310. The length L5 of the radiation adjustment plane 330 is arranged for adjusting the radiation pattern of the antenna structure 320. For example, if the length L5 of the radiation adjustment plane 330 approximates the distance D5 between the antenna structure 320 and the system ground plane 310, the radiation pattern of the antenna structure 320 can cover a relatively large spatial angle (e.g., a zenith angle from 0 to 120 degrees); conversely, if the length L5 of the radiation adjustment plane 330 is longer than the distance D5 between the antenna structure 320 and the system ground plane 310, the radiation pattern of the antenna structure 320 can cover a relatively small spatial angle (e.g., a zenith angle from 0 to 90 degrees). The distance between the antenna structure 320 and the radiation adjustment plane 330 is from 0.1 to 0.5 wavelength (0.1λ to 0.5λ) of the operation frequency band of the antenna structure 320, and it helps to generate constructive interferences.
Note that the above element sizes, element parameters, 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 communication device and antenna structure of the invention are 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 is to 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 |
|---|---|---|---|
| 105208204 | Jun 2016 | TW | national |
