Patent Publication Number: US-11024966-B2

Title: Antenna and terminal device having same

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to Chinese Patent Application No. 201811458116.4 filed on Nov. 30, 2018, the disclosure of which is hereby incorporated herein by reference in its entirety. 
     BACKGROUND 
     In the field of terminal devices, such as mobile phones and other mobile terminals, with the development trend of full screens and narrow bezels, and the increasing number of antennas in terminal devices, the working space for the antennas in the terminal device has become more limited. 
     SUMMARY 
     The present disclosure relates to the field of communications, and more specifically to an antenna and a terminal device having the same. 
     According to a first aspect of the present disclosure, there is provided an antenna, applicable in a terminal device having a metal body, where the antenna includes a first feed point, a second feed point and a first grounding point. The metal body includes a main body and a frame structure connected with the main body. The main body and the frame structure enclose a space to form a receiving area. The frame structure is provided with two slots spaced apart on a bottom thereof, and the two slots divide the frame structure into a first frame, a second frame and a third frame. The second frame and the third frame are disposed respectively on two sides of the first frame. The first feed point and the second feed point are spaced apart from each other in a same side of the main body, and the first grounding point is disposed in the receiving area. The first feed point is electrically connected with a first contact point on the first frame, the second feed point is electrically connected with a second contact point on the second frame; and the first grounding point is electrically connected with a third contact point of the first frame and is also electrically connected with a fourth contact point of the main body. An electrical connection body including the first feed point, the first contact point, the third contact point, the first grounding point, and the fourth contact point constitutes a first antenna, and an electrical connection body including the second feed point, the second contact point, and a junction point of the second frame and the main body constitutes a second antenna. The first grounding point is disposed adjacent to the second antenna. 
     According to a second aspect of the present disclosure, there is provided a terminal device including a metal body, where the metal body includes a main body and a frame structure connected with the main body. The main body and the frame structure enclose a space to form a receiving area. The frame structure is provided with two slots spaced apart on a bottom thereof, and the two slots divide the frame structure into a first frame, a second frame and a third frame. The second frame and the third frame are disposed respectively on two sides of the first frame. An end of the second frame away from the first frame is connected with one side of the main body, and an end of the third frame away from the first frame is connected with the other side of the main body. The first frame is provided with a first contact point and a third contact point, the second frame is provided with a second contact point, and the main body is provided with a fourth contact point. The terminal device further includes an antenna according to the above aspect. 
     It is to be understood that the above general descriptions and the below detailed descriptions are merely exemplary and explanatory, and are not intended to limit the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The accompanying drawings referred to in the specification are a part of this disclosure, and provide illustrative embodiments consistent with the disclosure and, together with the detailed description, serve to illustrate some embodiments of the disclosure. 
         FIG. 1  is a schematic structural diagram of an antenna according to some embodiments of the present disclosure; 
         FIG. 2  is a detailed schematic diagram showing a partial structure of the antenna provided in  FIG. 1 ; 
         FIG. 3A  is a block diagram showing a matching circuit of the antenna provided in  FIG. 2 ; 
         FIG. 3B  is another block diagram showing a matching circuit of the antenna provided in  FIG. 2 ; 
         FIG. 4  is another detailed schematic diagram showing a partial structure of the antenna provided in  FIG. 1 ; 
         FIG. 5  is a schematic structural diagram of another antenna according to some embodiments of the present disclosure; 
         FIG. 6  is a schematic structural diagram of still another antenna according to some embodiments of the present disclosure; and 
         FIG. 7  is a graph showing performance of an antenna according to some embodiments of the present disclosure, illustrating S 11  of a first antenna and a second antenna and isolation between the first antenna and the second antenna. 
     
    
    
     DETAILED DESCRIPTION 
     Examples will be described in detail herein, with the illustrations thereof represented in the drawings. When the following descriptions involve the drawings, like numerals in different drawings refer to like or similar elements unless otherwise indicated. The embodiments described in the following examples do not represent all embodiments consistent with the present disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the present disclosure as detailed in the appended claims. 
     The terms used in the present disclosure are for the purpose of describing particular examples only, and are not intended to limit the present disclosure. Terms determined by “a,” “the” and “said” in their singular forms in the present disclosure and the appended claims are also intended to include plurality, unless clearly indicated otherwise in the context. It should also be understood that the term “and/or” as used herein is and includes any and all possible combinations of one or more of the associated listed items. 
     It is to be understood that, although terms “first,” “second,” “third” and the like may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish one category of information from another. For example, without departing from the scope of the present disclosure, first information may be referred as second information; and similarly, second information may also be referred as first information. Depending on the context, the word “if” as used herein may be interpreted as “when” or “upon” or “in response to determining”. 
     Various embodiments of the present disclosure can improve performance of antennas working in restricted spaces. As the bandwidth of the terminal device becomes increasingly wider, the requirements on the environment become ever more demanding and the bezels become narrower, it may be difficult for a single antenna to cover the entire frequency band. Dual antennas have found more applications. However, it is desired to further improve isolation and efficiency of the dual antennas. 
       FIG. 1  is a schematic structural diagram of an antenna according to some embodiments of the present disclosure. The antenna of this example is applied to a terminal device having a metal body, and the terminal device can be a mobile terminal, such as a mobile phone, a tablet computer or the like, or can be a fixed terminal. 
     Referring to  FIG. 1 , the metal body  100  of the terminal device may include a main body  110  and a frame structure  120  connected with the main body  110 . The main body  110  and the frame structure  120  enclose a space to form a receiving area  130 . The frame structure  120  is provided with two slots  121  on a bottom thereof, and the two slots  121  are spaced apart. In the example, the two slots  121  divide the frame structure  120  into a first frame  122 , a second frame  123 , and a third frame  124 . The second frame  123  and the third frame  124  are disposed respectively on two sides of the first frame  122 . Further, in the example, the first frame  122  is provided with a first contact point  1221  and a third contact point  1222 , the second frame  123  is provided with a second contact point  1231 , and the main body  110  is provided with a fourth contact point  111 . 
     Taking the terminal device being a mobile phone as an example, the metal body  100  is a middle frame of the mobile phone, and the bottom of the frame structure  120  refers to a bottom of the mobile phone. The shape and size of the slots  121  can be set according to design requirements of the mobile phone. 
     In this example, the main body  110  and the frame structure  120  are all metal parts. The main body  110  has a cuboid or cubic structure, and the frame structure  120  is connected with both sides of the bottom of the main body  110 . Specifically, the second frame  123  is connected with one side of the main body  110 , and the third frame  124  is connected with the other side of the main body  110 . In this example, one end of the second frame  123  away from the slot  121  (the slot  121  between the first frame  122  and the second frame  123 ) is connected with one side of the main body  110 , and one end of the third frame  124  away from the slot  121  (the slot  121  between the first frame  122  and the third frame  124 ) is connected with the other side of the main body  110 . 
     In this example, the receiving area  130  can be a quadrilateral area, such as a rectangular area, a square area, or an area of other shapes. 
     Referring to  FIG. 1 , the antennas  200  may include a first feed point  1 , a second feed point  2 , and a first grounding point  3 . The first feed point  1  and the second feed point  2  are provided in the same side of the main body  110  (as shown in  FIG. 1 , the right half of the main body  110 ) and spaced apart from each other, and the first grounding point  3  is disposed in the receiving area  130 . In this example, the first feed point  1  is electrically connected with the first contact point  1221 , the second feed point  2  is electrically connected with the second contact point  1231 , and the first grounding point  3  is electrically connected with the third contact point  1222 , and is also electrically connected with the fourth contact point  111  on the main body  110 . 
     An electrical connection body formed by the first feed point  1 , the first contact point  1221 , the third contact point  1222 , the first grounding point  3 , and the fourth contact point  111  constitutes a first antenna, and an electrical connection body formed by the second feed point  2 , the second contact point  1231 , and a junction point  1232  of the second frame  123  and the main body  110  constitutes a second antenna. In addition, the first grounding point  3  of the example is disposed adjacent to the second antenna. 
     In the example of the present disclosure, the first feed point  1  and the second feed point  2  of the dual antenna  200  are provided in the same side of the main body  110  and spaced apart from each other, the first frame  122  is used to implement the first antenna, the second frame  123  is used to implement the second antenna, and an end of the first antenna adjacent to the second antenna is grounded, which improves the isolation between the first antenna and the second antenna and radiation efficiencies of the first antenna and the second antenna. 
     Optionally, the first feed point  1  and the second feed point  2  are spaced apart and disposed in one side of the main body  110  adjacent to the second frame  123  (that is, right half of the main body  110 ). Optionally, the first feed point  1  and the second feed point  2  are spaced apart and disposed in one side of the main body  110  adjacent to the third frame  124  (that is, left half of the main body  110 ). This example is further described by taking the first feed point  1  and the second feed point  2  being spaced apart and disposed in one side of the main body  110  adjacent to the second frame  123  as an example. 
     Referring to  FIG. 1 , in this example, the first grounding point  3  is disposed over an end of the first frame  122  adjacent to the second frame  123 . 
     The position of the first contact point  1221  and the third contact point  1222  on the first frame  122  can be selected according to design requirements on performance such as frequency band of the first antenna. 
     Referring to  FIG. 1 , in this example, the first contact point  1221  is disposed at an end of the first frame  122  adjacent to the third frame  124 , and the third contact point  1222  is disposed at an end of the first frame  122  adjacent to the second frame  123 . 
     The position of the second contact point  1231  on the second frame  123  can be selected according to design requirements on performance such as frequency band of the second antenna. Optionally, the second contact point  1231  is disposed on a side of the second frame  123  away from the first frame  122 . 
     In addition, in this example, the fourth contact point  111  is spaced apart from the first feed point  1  and the second feed point  2 , respectively. Referring to  FIG. 1  again, in this example, the fourth contact point  111  is disposed on a side of the main body  110  facing the receiving area  130 . Of course, the fourth contact point  111  may also be disposed at other positions of the main body  110 , and specifically, the position of the fourth contact point  111  on the main body  110  can be selected according to design requirements on performance such as the frequency band of the first antenna, the isolation between the first antenna and the second antenna, and the like. 
     In this example, the antenna  200  further includes a first trace  4 , a second trace  5 , and a third trace  6 . The first feed point  1  is electrically connected with the first contact point  1221  through the first trace  4 , and the second feed point  2  is electrically connected with the second contact point  1231  through the second trace  5 , and the first grounding point  3  is electrically connected with the third contact point  1222  and the fourth contact point  111  through the third trace  6 . 
     The shape and size of the first trace  4  and the shape and size of the third trace  6  can be selected according to design requirements on performance such as the frequency band of the first antenna, and the shape and size of the second trace  5  can be selected according to design requirements on performance such as the frequency band of the second antenna. 
     Referring also to  FIG. 1 , the first trace  4  may include a first segment and a second segment. The first segment is connected with the first contact point  1221 . The second segment has one end connected with one end of the first segment away from the first contact point  1221 , and the other end connected with the first feed point  1 . In this example, the first segment and the second segment are disposed as a bending member, that is, a certain angle is formed between the first segment and the second segment. By adopting such a configuration, the performance of the first antenna can be improved. Optionally, the first segment is perpendicularly connected with the first frame  122 . Referring to  FIG. 1 , in this example, the third trace  6  is perpendicularly connected with a side of the first frame  122  and the main body  110  facing the receiving area  130 , respectively. 
     In some embodiments, a frequency range of the first antenna is (800 MHz, 2170 MHz). That is, the frequency band of the first antenna is greater than or equal to 800 MHz, and less than or equal to 2170 MHz, which can achieve coverage of low and intermediate frequency bandwidths. A frequency range of the second antenna is (2300 MHz, 2690 MHz). That is, the frequency band of the second antenna is greater than or equal to 2300 MHz, and less than or equal to 2690 MHz, which can achieve coverage of high frequency bandwidths. 
     The form of the first antenna and the second antenna can be designed as needed. For example, in some embodiments, the first antenna is in the form of a loop. Of course, the first antenna can also be designed in other forms as needed. 
     In some embodiments, the second antenna is in the form of an Inverted-F-Antenna (IFA). Of course, the second antenna can also be designed in other forms as needed. 
     In this example, the first antenna is in the form of a loop, and the second antenna is in the form of an IFA. 
     Further, in this example, a first matching circuit  7  is connected in series between the first grounding point  3  and the third contact point  1222  and/or between the first grounding point  3  and the fourth contact point  111 . Referring to  FIG. 2 , in some embodiments, a first matching circuit  7  is connected in series between the first grounding point  3  and the fourth contact point  111 . Specifically, referring to  FIG. 3A , the first matching circuit  7  may include a resistor-inductor-capacitor (RLC) circuit  71  and a switch  72  configured to control the RLC circuit  71 . The RLC circuit  71  includes a resistor, a capacitor, and an inductor. By switching the RLC circuit  71  to different impedance levels with the switch  72 , the first antenna can achieve coverage of low frequency bandwidths. 
     In one specific example, referring to  FIG. 3B , the RLC circuit  71  includes a first RLC sub-circuit  711 , a second RLC sub-circuit  712 , a third RLC sub-circuit  713 , and a fourth RLC sub-circuit  714 . The switch  72  is a single-pole four-throw switch, and the single-pole four-throw switch is used to control the first matching circuit  7  to select one or more of the first RLC sub-circuit  711 , the second RLC sub-circuit  712 , the third RLC sub-circuit  713 , and the fourth RLC sub-circuit  714 . 
     Optionally, the first RLC sub-circuit  711 , the second RLC sub-circuit  712 , the third RLC sub-circuit  713 , and the fourth RLC sub-circuit  714  have different impedances. By controlling one of the first RLC sub-circuit  711 , the second RLC sub-circuit  712 , the third RLC sub-circuit  713 , and the fourth RLC sub-circuit  714  to be switched on and connected in series between the first grounding point  3  and the fourth contact point  111  with the single-pole four-throw switch, the frequency bands of the first antenna can fully cover low and intermediate frequency bandwidths. 
     In some embodiments, referring to  FIG. 4 , the antenna  200  may further include a tuning inductor  8 . The first matching circuit  7  is connected in series with the tuning inductor  8  between the fourth contact point  111  and the first grounding point  3  to shift the resonance frequency of the first antenna at 2170 MHz to lower frequency, thereby increasing the isolation between the first antenna and the second antennas. 
     In addition, the second antenna may include a second matching circuit between the fourth contact point  111  and the second contact point  1231 . The bandwidth and frequency offset of the second antenna can be adjusted by adjusting the position of the second contact point  1231  on the second frame  123  and adjusting the second matching circuit of the second antenna. 
     To further optimize the isolation between the first antenna and the second antenna, referring to  FIG. 5 , the antenna  200  may further include a second grounding point  9 . The second grounding point  9  is disposed in the receiving area  130 , and spaced apart from the first grounding point  3 . The second grounding point  9  is electrically connected with a fifth contact point  1223  of the first frame  122  and is electrically connected with a sixth contact point  112  of the main body  110 . 
     Optionally, the second grounding point  9  is disposed between the first grounding point  3  and the second frame  123 . Further, the fifth contact point  1223  is disposed between the third contact point  1222  and the second frame  123 , and the sixth contact point  112  is disposed between the fourth contact point  111  and a junction point  1232  of the main body  110  and the second frame  123 . 
     The position of the fifth contact point  1223  on the first frame  122  and the position of the sixth contact point  112  on the main body  110  can be selected according to design requirements on the isolation between the first antenna and the second antenna. Optionally, the fifth contact point  1223  is disposed at an end of the first frame  122  adjacent to the second frame  123 . Optionally, the sixth contact point  112  can be disposed on a side of the main body  110  facing the receiving area  130 . 
     Further, in this example, the antenna  200  also includes a fourth trace  10 . The second grounding point  9  is electrically connected with the fifth contact point  1223  through the fourth trace  10 , and is electrically connected to the sixth contact point  112  through the fourth trace  10 . The size of the fourth trace  10  can be set according to design requirements on the isolation between the first antenna and the second antenna. 
     Referring to  FIG. 6 , in some embodiments, the antenna  200  also includes a slit  11  disposed on a bottom side of the main body  110  and adjacent to the second frame  123  and/or the third frame  124 . The opening of the slit  11  faces the receiving area. The slit  11  is provided to optimize the performance of the first antenna and the second antenna. The size of the slit  11  and the position of the slit  11  on the main body  110  can be set according to requirements on performance of the first antenna and the second antenna. 
     The material of each of the above traces can be copper or other metal such as silver, aluminum or some other suitable options. Optionally, the trace is made of copper foil. It is to be noted that the present disclosure does not limit the material of the trace, and any material capable of signal transmission is within the protection scope of the present disclosure. Each trace of the present disclosure is patterned in a corresponding region. 
       FIG. 7  is a graph showing the performance of the antenna according to some embodiments of the present disclosure. Si  1  (return loss characteristics) of the first antenna and the second antenna and isolation between the first antenna and the second antenna are illustrated. In the graph, the abscissa is the resonant frequency, and for S 11 , the ordinate is the value of Si  1  in dB, and for the isolation, the ordinate is the isolation value. From  FIG. 7 , it can be observed that the value of S 11  of the first antenna and the second antenna are both relatively small, thus the radiation efficiencies of the first antenna and the second antenna are high. In addition, the smaller the isolation value is, the better the isolation is. It can also be observed from  FIG. 7  that the third valley of the S 11  curve of the first antenna corresponds to a resonant frequency of smaller than 2170 MHz. In a case where the first matching circuit  7  and the tuning inductor  8  are not included in the first antenna, the third valley of a corresponding S 11  curve of the first antenna corresponds to a resonant frequency of 2170 MHz. Therefore, in the example of the present disclosure, the resonance frequency of the first antenna at 2170 MHz band is shifted to lower frequency, and the isolation between the first antenna and the second antenna is increased. 
     Various embodiments of the present disclosure can have one or more of the following advantages: by arranging the first feed point and the second feed point of the dual antenna together, implementing the first antenna with the first frame, implementing the second antenna with the second frame, and grounding the end of the first antenna adjacent to the second antenna, it can improve the isolation between the first antenna and the second antenna and the radiation efficiencies of the first antenna and the second antenna. 
     In the present disclosure, the terms “installed,” “connected,” “coupled,” “fixed” and the like shall be understood broadly, and can be either a fixed connection or a detachable connection, or integrated, unless otherwise explicitly defined. These terms can refer to mechanical or electrical connections, or both. Such connections can be direct connections or indirect connections through an intermediate medium. These terms can also refer to the internal connections or the interactions between elements. The specific meanings of the above terms in the present disclosure can be understood by those of ordinary skill in the art on a case-by-case basis. 
     In the description of the present disclosure, the terms “one embodiment,” “some embodiments,” “example,” “specific example,” or “some examples,” and the like can indicate a specific feature described in connection with the embodiment or example, a structure, a material or feature included in at least one embodiment or example. In the present disclosure, the schematic representation of the above terms is not necessarily directed to the same embodiment or example. 
     Moreover, the particular features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, various embodiments or examples described in the specification, as well as features of various embodiments or examples, can be combined and reorganized. 
     While this specification contains many specific implementation details, these should not be construed as limitations on the scope of any claims, but rather as descriptions of features specific to particular implementations. Certain features that are described in this specification in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. 
     Moreover, although features can be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination can be directed to a subcombination or variation of a subcombination. 
     It is intended that the specification and embodiments be considered as examples only. Other embodiments of the disclosure will be apparent to those skilled in the art in view of the specification and drawings of the present disclosure. That is, although specific embodiments have been described above in detail, the description is merely for purposes of illustration. It should be appreciated, therefore, that many aspects described above are not intended as required or essential elements unless explicitly stated otherwise. 
     Various modifications of, and equivalent acts corresponding to, the disclosed aspects of the example embodiments, in addition to those described above, can be made by a person of ordinary skill in the art, having the benefit of the present disclosure, without departing from the spirit and scope of the disclosure defined in the following claims, the scope of which is to be accorded the broadest interpretation so as to encompass such modifications and equivalent structures. 
     It should be understood that “a plurality” or “multiple” as referred to herein means two or more. “And/or,” describing the association relationship of the associated objects, indicates that there may be three relationships, for example, A and/or B may indicate that there are three cases where A exists separately, A and B exist at the same time, and B exists separately. The character “/” generally indicates that the contextual objects are in an “or” relationship. 
     In the present disclosure, it is to be understood that the terms “lower,” “upper,” “under” or “beneath” or “underneath,” “above,” “front,” “back,” “left,” “right,” “top,” “bottom,” “inner,” “outer,” “horizontal,” “vertical,” and other orientation or positional relationships are based on example orientations illustrated in the drawings, and are merely for the convenience of the description of some embodiments, rather than indicating or implying the device or component being constructed and operated in a particular orientation. Therefore, these terms are not to be construed as limiting the scope of the present disclosure. 
     Moreover, the terms “first” and “second” are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, elements referred to as “first” and “second” may include one or more of the features either explicitly or implicitly. In the description of the present disclosure, “a plurality” indicates two or more unless specifically defined otherwise. 
     In the present disclosure, a first element being “on” a second element may indicate direct contact between the first and second elements, without contact, or indirect geometrical relationship through one or more intermediate media or layers, unless otherwise explicitly stated and defined. Similarly, a first element being “under,” “underneath” or “beneath” a second element may indicate direct contact between the first and second elements, without contact, or indirect geometrical relationship through one or more intermediate media or layers, unless otherwise explicitly stated and defined. 
     Some other embodiments of the present disclosure can be available to those skilled in the art upon consideration of the specification and practice of the various embodiments disclosed herein. The present application is intended to cover any variations, uses, or adaptations of the present disclosure following general principles of the present disclosure and include the common general knowledge or conventional technical means in the art without departing from the present disclosure. The specification and examples can be shown as illustrative only, and the true scope and spirit of the disclosure are indicated by the following claims.