Abstract:
An antenna structure of an information communication terminal, the antenna structure including: a frame having a three dimensional shape; an antenna pattern formed in the frame; and a circuit lumped element mounted on a surface of the antenna pattern. In the antenna structure, an antenna is directly provided on the frame such that a sufficient antenna characteristic can be ensured in a small space, thereby realizing a slim and miniaturized information communication terminal.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of Korean Patent Application No. 2008-24368, filed Mar. 17, 2008 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    Aspects of the present invention relate to an antenna structure, and more particularly, to an antenna structure having a three dimensional shape that enables a compact configuration. 
         [0004]    2. Description of the Related Art 
         [0005]    With recent developments in wireless communication techniques, information communication terminals (such as mobile phones, personal data assistants (PDAs), global positioning systems (GPSs), portable multimedia players (PMPs), etc.) have been popularized and generalized, and studies have been actively conducted to make the information communication terminals even more compact than present. In particular, in manufacturing slim and miniaturized information communication terminals, a design of an antenna of the terminals is particularly important. As the information communication terminals are gradually slimmed and miniaturized, an ability to mount parts is further reduced. Furthermore, in order to cope with multiple wireless services, a single information communication terminal includes a plurality of antennas. However, there is a space limitation in the installation of the multiple antennas in an information communication terminal. For example, volume occupancy of a printed board assembly (PBA) on an information communication terminal gradually increases as the information communication terminals are slimmed and miniaturized. 
         [0006]    In order to manufacture slim and miniaturized information communication terminals, there has been proposed a printed circuit board (PCB) patch type antenna, in which an antenna pattern is realized on a PCB and a radio frequency (RF) switch is mounted on the PCB as necessary. However, a PCB patch type antenna having high efficiency cannot be realized, and there is little space for the installation of the PCB in the information communication terminals. 
         [0007]    Meanwhile, attempts have been conducted to realize an antenna by attaching a conductive metal sheet on a frame having a three dimensional shape. However, since the metal sheet type composite antenna is made by a press process, there is a difficulty in forming a metal sheet type antenna pattern having a complex and minute shape. For example, presently, a minute antenna pattern that can be realized in the metal sheet type composite antenna has a width of only 0.8 mm. Also, since the structure of the antenna pattern formed in the metal sheet type composite antenna is formed by heat stacking, there is difficulty in soldering additional circuit lumped elements on the metal sheet type composite antenna. Furthermore, since the heat stacking occupies space, the heat stacking is not suitable for miniaturizing the antenna pattern structure. Moreover, there is a difficulty in forming an antenna pattern having a length sufficient to design an antenna due to the size limitation of a surface of the frame of the information communication terminal. 
       SUMMARY OF THE INVENTION 
       [0008]    Aspects of the present invention provide an antenna structure that is suitable for information communication terminals that are gradually miniaturized. 
         [0009]    According to an aspect of the present invention, there is provided an antenna structure of an information communication terminal, the antenna structure including: a frame having a three dimensional shape; an antenna pattern formed in the frame; and a circuit lumped element mounted on a surface of the antenna pattern. 
         [0010]    According to another aspect of the present invention, there is provided an antenna structure of an information communication terminal, the antenna structure including: a frame having a three dimensional shape and at least one groove; and an antenna pattern formed in the frame, wherein a portion of the antenna pattern is formed on a surface of the at least one groove. 
         [0011]    In an aspect of the invention, the portion of the antenna pattern may be formed in a lengthwise direction of one of the grooves. 
         [0012]    In an aspect of the invention, the portion of the antenna pattern may be formed in a direction perpendicular to the lengthwise direction of one of the grooves. 
         [0013]    In an aspect of the invention, the circuit lumped element may be a resistor, a capacitor, and/or an inductor. 
         [0014]    In an aspect of the invention, the antenna structure may further include a matching circuit mounted on a surface of the antenna pattern. 
         [0015]    In an aspect of the invention, the antenna structure may further include a radio frequency (RF) signal transformation tuner mounted on a surface of the antenna pattern. 
         [0016]    In an aspect of the invention, the antenna structure may further include an RF module mounted on a surface of the antenna pattern. 
         [0017]    According to another aspect of the present invention, there is provided an information communication terminal, including: a frame having a three dimensional shape; and an antenna pattern formed inside the frame. 
         [0018]    Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which: 
           [0020]      FIG. 1  is a schematic perspective view of an antenna structure according to an embodiment of the present invention; 
           [0021]      FIG. 2  is a schematic perspective view of an antenna structure according to another embodiment of the present invention; 
           [0022]      FIG. 3A  is a cross-sectional view of a width of a conventional antenna pattern as a comparative example; 
           [0023]      FIG. 3B  is a cross-sectional view of a width of an antenna pattern in the antenna structure of  FIG. 2 ; 
           [0024]      FIG. 4  is a graph showing an S parameter characteristic of the antenna structure of  FIG. 2 ; 
           [0025]      FIG. 5  is a schematic perspective view of an antenna structure according to another embodiment of the present invention; 
           [0026]      FIG. 6A  is a cross-sectional view of a width of a conventional antenna pattern as a comparative example; 
           [0027]      FIG. 6B  is a cross-sectional view of an antenna pattern in a lengthwise direction of the antenna structure of  FIG. 5 ; 
           [0028]      FIG. 7  is a graph showing an S parameter characteristic of the antenna structure of  FIG. 5 ; and 
           [0029]      FIG. 8  is a schematic perspective view of an antenna structure according to another embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0030]    Reference will now be made in detail to the present embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures. 
         [0031]      FIG. 1  is a schematic perspective view of an antenna structure  100  according to an embodiment of the present invention. Referring to  FIG. 1 , the antenna structure  100  includes a frame  110  having a three dimensional shape, an antenna pattern  120  formed in the antenna structure  100 , and a circuit lumped element  130  mounted on the antenna pattern  120 . 
         [0032]    The three dimensional shape frame  110  may be a molded structure of an information communication terminal (for example, a molded case of a mobile phone, a PDA, a GPS, a PMP, etc.). The antenna pattern  120  is formed as a conductive metal pattern in the frame  110 . For example, if the frame  110  is a molded case of an information communication terminal (such as a mobile phone), the antenna pattern  120  may be formed in an inner side of the frame  110 , (i.e., within the molded case). Such an antenna pattern  120  may be formed using a molded interconnect device (MID) method in which a three dimensional electrical circuit is realized on a surface of a frame. However, it is understood that aspects of the present invention are not limited to the various MID methods. For example, the metal pattern may be formed by compressing a metal sheet. The circuit lumped element  130  includes a resistor  131 , a capacitor  132 , and an inductor  133 , which are compositely mounted on an outer side of the frame  110  and connected to the antenna pattern  120  through openings on the frame  110 . In a case where the antenna pattern  120  cannot be formed in a pattern having a sufficient length on a surface of the frame  110  due to a space limitation, a multi-band characteristic of an antenna may be realized by compositely using the circuit lumped element  130 . 
         [0033]      FIG. 2  is a schematic perspective view of an antenna structure  200  according to another embodiment of the present invention. Referring to  FIG. 2 , the antenna structure  200  includes a frame  210  having a three dimensional shape, and an antenna pattern  220  formed on the frame  210 . 
         [0034]    The frame  210  may be a molded structure of an information communication terminal (for example, a molded case of a mobile phone, a PDA, a GPS, a PMP, etc.). The frame  210  according to the current embodiment (i.e., the molded structure) includes at least one long groove  210   a . For example, if the frame  210  is a molded case of an information communication terminal (such as a mobile phone), the long groove  210   a  may be formed on an inner side of the frame  210  (i.e., within the molded case of the mobile phone). The antenna pattern  220  is formed on the frame  210  using a conductive metal pattern. Furthermore, at least a portion of the antenna pattern  220  is formed to extend along a lengthwise direction of at least one of the long grooves  210   a , and a cross-section of the antenna pattern  220  has a corrugated shape in a widthwise direction of the antenna pattern  220 . That is, the antenna pattern  220  is formed in a corrugated shape by bending in a width direction  290  of the antenna pattern  220 . Such an antenna pattern  220  may be formed by, for example, using an MID method, though it is understood that aspects of the present invention are not limited thereto, as described above. 
         [0035]      FIG. 3A  is a cross-sectional view of a width of a conventional antenna pattern.  FIG. 3B  is a cross-sectional view of a width of the antenna pattern  220  in the antenna structure  200  of  FIG. 2 , for example, taken along the widthwise direction  290 . Referring to  FIGS. 3A and 3B , if a conventional antenna pattern formed on a flat surface of a frame is 2.5 mm, the corresponding antenna pattern  220 , according to aspects of the present invention, formed on surfaces of two long grooves  210  has a width of 4.0 mm because portions of the antenna pattern  220  bend in the width direction  290  of the antenna pattern  220 . In this manner, the antenna structure  200  according to the current embodiment can widen the width of the antenna pattern  220  by forming the long grooves  210  on the frame  210  that has a limited surface area. While shown as being rectangular in shape, it is understood that the corrugated cross section can have triangular, circular, or other shapes. 
         [0036]      FIG. 4  is a graph showing an S parameter characteristic of the antenna structure  200  of  FIG. 2 . Referring to  FIG. 4 , the dotted line indicates an S parameter characteristic curve of the conventional antenna structure having a relatively narrow width as compared to that of the antenna structure  200 , and the solid line indicates an S parameter characteristic curve of an antenna structure  200  according to the current embodiment. Referring to  FIG. 4 , the antenna structure  200  according to the current embodiment can achieve a greater broadband by sufficiently widening the width of the antenna pattern  220 . 
         [0037]    Referring to  FIG. 2  again, the shown antenna structure  200  further includes the circuit lumped element  130  on a surface of the antenna pattern  220 . The circuit lumped element  130  includes one or more of a resistor  131 , a capacitor  132 , and an inductor  133 . The circuit lumped element  130  is described above in regards to the embodiment illustrated in  FIG. 1 , and thus, the description thereof will not be repeated herein. In the current embodiment, while the circuit lumped element  130  is not required in all aspects of the invention, multi-band characteristics of an antenna may be readily realized by using the circuit lumped element  130 . 
         [0038]      FIG. 5  is a schematic perspective view of an antenna structure  300  according to another embodiment of the present invention. Referring to  FIG. 5 , the antenna structure  300  includes a frame  310  having a three dimensional shape and an antenna pattern  320  formed in the frame  310 . The frame  310  may be a molded frame of an information communication terminal (for example, a molded case of a mobile phone, a PDA, a GPS, a PMP, etc.). The frame  310  according to the current embodiment (i.e., the molded frame) includes at least one long groove  310   a . For example, if the frame  310  is a molded case of an information communication terminal (such as a mobile phone), the long groove  310   a  may be formed on an inner side of the frame  310  (i.e., within the molded case). The antenna pattern  320  is formed in the frame  310  using a conductive metal pattern. Furthermore, at least a portion of the antenna pattern  320  is formed across a lengthwise direction of at least one of the long grooves  310   a , and a cross-section of the antenna pattern  320  in a lengthwise direction  390  of the antenna pattern  320  has a corrugated shape. That is, the antenna pattern  320  is formed in a corrugated shape by bending in the lengthwise direction  390  of the antenna pattern  320 . Such an antenna pattern  320  may be formed by, for example, using an MID method, though it is understood that aspects of the present invention are not limited thereto, as described above. 
         [0039]      FIG. 6A  is a cross-sectional view of a width of a conventional antenna pattern as a comparative example.  FIG. 6B  is a cross-sectional view of the antenna pattern  320  in the lengthwise direction  390  of the antenna structure  300  of  FIG. 5 . Referring to  FIGS. 6A and 6B , if a length of a conventional antenna pattern formed on a flat surface of a frame is 15 mm, the corresponding antenna pattern  320 , according to aspects of the present invention, formed on surfaces of two long grooves  310   a  has a length of 25 mm because the antenna pattern  320  is bent in the lengthwise direction  390  (refer to  FIG. 5 ) of the antenna pattern  320 . In this manner, the antenna structure  200  according to the current embodiment can lengthen the antenna pattern  200  by forming the long grooves  310  on the frame  310  that has a limited surface area. 
         [0040]      FIG. 7  is a graph showing an S parameter characteristic of the antenna structure  300  of  FIG. 5 . Referring to  FIG. 7 , the dotted line indicates an S parameter characteristic curve of a conventional antenna structure having a relatively short length as compared to that of the antenna structure  300 , and the solid line indicates an S parameter characteristic curve of the antenna structure  300  according to the current embodiment. Referring to  FIG. 7 , the antenna structure  300  according to the current embodiment can ensure a band characteristic in a low frequency region by sufficiently lengthening the length of the antenna pattern  320 . That is, the antenna structure  300  according to the current embodiment can increase a band characteristic in a low frequency region by securing a sufficient length of the antenna pattern  320  on the frame  310  that has a limited surface area. 
         [0041]    Referring to  FIG. 5  again, the antenna structure  300  further includes the circuit lumped element  130  on a surface of the antenna pattern  320 . The circuit lumped element  130  includes at least one of the resistor  131 , the capacitor  132 , and the inductor  133 . The circuit lumped element  130  is described in the foregoing embodiment, and thus, the description thereof will not be repeated herein. In the current embodiment, the circuit lumped element  130  is not required in all aspects of the invention. However, multi-band characteristics of an antenna may be readily realized by using the circuit lumped element  130 . 
         [0042]      FIG. 8  is a schematic perspective view of an antenna structure (not shown) according to another embodiment of the present invention. Referring to  FIG. 8 , the antenna structure includes a frame  410 , an antenna pattern  420  formed in the frame  410 , a radio frequency (RF) chip  450  and circuits  460  mounted on the frame  410 . 
         [0043]    The frame  410  may be, for example, a molded structure of an information communication terminal (for example, a molded case of a mobile phone, a PDA, a GPS, a PMP, etc.). The antenna pattern  420  is formed of a conductive metal pattern in the frame  410 . The antenna pattern  420  may bend in a lengthwise direction and/or a widthwise direction of the antenna pattern  420  as in the foregoing embodiments. In the current embodiment, the RF chip  450  and the circuits  460 , used by an antenna, are directly mounted on a portion of the antenna pattern  420 . The circuits  460  may include a resistor, a capacitor, an inductor, a matching circuit, and/or an RF signal transformation tuner, which are realized by mounted parts on a surface of the antenna pattern  420 . The numerical references  461  and  462  denote illustrative examples of a circuit lumped element, a matching circuit, and an RF signal transformation tuner. In this manner, since circuits of an antenna are directly mounted on the frame  410 , a matching circuit, an RF signal transformation tuner, and an RF module can be integrally mounted on an antenna structure. Thus, a space occupied by the antenna structure in an information communication terminal that uses the frame  410  as a main frame can be minimized. 
         [0044]    In the current embodiment, a matching circuit, an RF signal transformation tuner, and an RF module are described as integrally mounted on the antenna structure  400 . However, it is understood that aspects of the present invention are not limited thereto. That is, the matching circuit, the RF signal transformation tuner, and the RF module may be selectively mounted on the antenna structure  400 . 
         [0045]    Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.