Abstract:
A phase shifter including a substrate, a plurality of first transmission lines, a plurality of second transmission lines, and a coupling portion is described. After the phase shifter feeds a signal into the first transmission lines, the first transmission lines assign the signal to the second transmission lines. Moreover, the coupling portion moves to change an area of the second transmission lines shielded by the coupling portion, so as to change the phase of the signal transferred by each of the second transmission lines.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a phase shifter. More particularly, the present invention relates to a phase shifter having a movable coupling portion. 
         [0003]    2. Related Art 
         [0004]    With the development of wireless communication technology, wireless communication products are playing an increasingly important role in people&#39;s daily life. Meanwhile, the demands on the communication products have been transited from mere voice and message transmission in the past to image transmission, online browsing, and so on. Moreover, the products are required to be light, thin, short, small and provided with various types of communication services, instead of neglecting the appearance in the past. The current situation shows that the communication products are developing towards broadband and multiplexing integration. Therefore, antennae used for transmitting/receiving signals must have a wide bandwidth, so as to achieve a high transmission speed and provide multiple communication services. 
         [0005]    Phase shifters, generally used in the fields such as communication, gauging instruments, and control, can be widely applied, but also have many problems to be solved. For example, a type of phase shifter applicable to various base station antennae is still in need; the signal coupling efficiency is low due to the structure of the metal material; different phases cannot be output simultaneously, and the phase of an output signal can only be changed at a single output portion under the control of a phase shifter; or noises are generated during the phase shift in a contact signal transmission mode. In addition, the common phase shifters all have a huge size, and are complicated to fabricate due to the metal structures thereof. 
       SUMMARY OF THE INVENTION 
       [0006]    Accordingly, the present invention is directed to a phase shifter, so as to solve the above problem that different phases cannot be output simultaneously and meanwhile eliminate noises generated during the phase shift by adopting a non-contact signal transmission mode. 
         [0007]    A phase shifter including a substrate, a plurality of second transmission lines, a coupling portion, and a plurality of output portions is provided. The substrate is formed with a plurality of first transmission lines and an input portion, in which the first transmission lines are respectively coupled to the input portion, for transmitting a signal received by the input portion. The second transmission lines are formed on the substrate, and each has a first end electrically connected to one of the first transmission lines correspondingly. The coupling portion, disposed corresponding to and moving relative to the second transmission lines to change an area of the second transmission lines shielded by the coupling portion, is used for coupling the signal received by each of the second transmission lines, so as to change the phase of the signal transmitted by each of the second transmission lines. Each of the output portions is electrically connected to a second end of each of the second transmission lines, for receiving the signal output by the corresponding second transmission line. 
         [0008]    The phase shifter of the present invention further includes a plurality of power distribution units electrically connected to the plurality of first transmission lines, so as to assign the signal received by the input portion to the first transmission lines for transmission. 
         [0009]    In the phase shifter of the present invention, the coupling portion is a step-like dielectric plate formed by connecting a plurality of dielectric materials having a length greater than that of the second transmission lines. Of course, the coupling portion may also be a step-like metal plate formed by connecting a plurality of metal materials having a length greater than that of the second transmission lines. 
         [0010]    The phase shifter of the present invention controls the area of each of the second transmission lines shielded by the coupling portion, such that after the coupling portion that shields different areas of the second transmission lines couples the signal received by the second transmission lines, the second transmission lines output signals with different phases. In addition, the phase of the signal output by each of the second transmission lines is changed by moving the coupling portion. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The present invention will become more fully understood from the detailed description given herein below for illustration only, and thus are not limitative of the present invention, and wherein: 
           [0012]      FIG. 1  is a schematic view of a first embodiment of the present invention; 
           [0013]      FIG. 2  is another schematic view of the first embodiment of the present invention; and 
           [0014]      FIG. 3  is a schematic view of a second embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0015]      FIG. 1  is a schematic view of a first embodiment of the present invention. Referring to  FIG. 1 , the phase shifter  100  includes a substrate  21 , a plurality of power distribution units  22 , a plurality of second transmission lines  23 , a coupling portion  24 , and a plurality of output portions  29 . 
         [0016]    The substrate  21  is formed with a plurality of first transmission lines  25  and an input portion  26 , in which the first transmission lines  25  transmit a signal fed in by the input portion  26 . The phase shifter  100  is disposed inside a case  27 . The case  27  includes a signal feed-in portion  28  for feeding the signal into the input portion  26 . Further, the signal feed-in portion  28  penetrates a side surface  27   a  of the case  27  and is connected to the substrate  21 . The signal feed-in portion  28  has an inner signal line  28   a  and an outer wrapping metal  28   b , in which the outer wrapping metal  28   b  is connected to the side surface  27   a  of the case  27 , and the inner signal line  28   a  is connected to the input portion  26  on the substrate  21 . The power distribution units  22  are electrically connected to the first transmission lines  25 , so as to assign the signal received by the input portion  26  to the first transmission lines  25  for transmission. 
         [0017]    The second transmission lines  23  each has a first end electrically connected to one of the first transmission lines  25 , and a second end electrically connected to one of the output portions  29  correspondingly. Each of the output portions  29  receives the signal output by the corresponding second transmission line  23 . The second transmission lines  23 , having the same length and arranged in parallel, are formed on the substrate  21  with an equal spacing from the output portions  29 . The case  27  further includes a plurality of signal feed-out portions  30  for receiving and feeding out the signal transmitted by the output portions  29 . The signal feed-out portions  30  penetrate another side surface  27   b  opposite to the side surface  27   a  of the case  27  and are connected to the substrate  21 . Each of the signal feed-out portions  30  has an inner signal line  30   a  and an outer wrapping metal  30   b , in which the outer wrapping metal  30   b  is connected to the side surface  27   b  of the case  27 , and the inner signal line  30   a  is connected to one of the output portions  29  on the substrate  21 . The signal feed-out portions  30  feed out the signal through the output portions  29 . Each of the second transmission lines  23  is a serpentine metal line, and of course, may be a rectangular metal line or in other geometrical shapes. 
         [0018]    The coupling portion  24  has two movable portions  24   a  perpendicular to two sides of the coupling portion  24  respectively. The two movable portions  24   a  penetrate and are exposed out of two openings  27   d  in two side surfaces  27   c  of the case  27 . The coupling portion  24  is driven to move through the two movable portions  24   a  exposed out of the two openings  27   d . In addition, the coupling portion  24 , disposed corresponding to and moving relative to the second transmission lines  23  to change an area of the second transmission lines  23  shielded by the coupling portion  24 , is used for coupling the signal received by each of the second transmission lines  23 , so as to change the phase of the signal transmitted by each of the second transmission lines  23 .  FIG. 2  is another schematic view of the first embodiment of the present invention. Referring to  FIGS. 2 and 1 , the position on each of the second transmission lines  23  shielded by the coupling portion  24  is changed, so the shielded area of each second transmission line  23  is different. Therefore, in  FIGS. 1 and 2 , the phase of the signal output by each of the second transmission lines is different. 
         [0019]    The coupling portion  24  is a step-like dielectric plate formed by connecting a plurality of dielectric materials having a length greater than that of the second transmission lines  23 . Of course, the coupling portion  24  may also be a step-like metal plate formed by connecting a plurality of metal materials having a length greater than that of the second transmission lines  23 . The coupling portion  24  has two movable portions  24   a  perpendicular to two sides of the coupling portion  24 . In addition, the two movable portions  24   a  penetrate and are exposed out of two openings  27   d  in two side surfaces  27   c  of the case  27 . 
         [0020]    In the phase shifter  100  of the present invention, a signal is fed by the signal feed-in portion  28  into the input portion  26  on the substrate  21 , and the energy of the signal is uniformly distributed to the plurality of first transmission lines  25  through the plurality of power distribution units  22 . When the signal on each of the first transmission lines  25  is transmitted to one of the second transmission lines  23  correspondingly, the coupling portion  24  is driven to move through the control of the two movable portions  24   a , so as to shield different areas of the second transmission lines  23 . As such, the coupling portion  24  that shields different areas of the second transmission lines  23  couples the signal received by each of the second transmission lines  23 , changes the phase of the signal, and transmits the signal to each of the output portions  29 . Afterward, the signal is fed out for transmission by each of the signal feed-out portions  30  corresponding to each of the output portions  29 . Thereby, the phase angle of the signal output by each of the output portions  29  differs from one another. Further, in the phase shifter  100  of the present invention, the position on each of the second transmission lines  23  shielded by the coupling portion  24  is changed by moving the coupling portion  24 , so the shielded area of each second transmission line  23  is different, and thus the phase of the signal output by each of the output portions  29  is changed accordingly. 
         [0021]      FIG. 3  is a schematic view of a second embodiment of the present invention. Referring to  FIG. 3 , the structure of the phase shifter  100  of this embodiment has been disclosed in the first embodiment, so the same parts can be known by comparison and will not be repeated herein again. This embodiment is characterized in the following aspects. The second transmission lines  23 , having the same length and arranged step-like, are formed on the substrate  21  with a progressive spacing from the output portions  29 . Besides, the coupling portion  24  is a rectangular dielectric plate formed by connecting a plurality of dielectric materials having a length greater than that of the second transmission lines  23 . Of course, the coupling portion  24  may also be a rectangular metal plate formed by connecting a plurality of metal materials having a length greater than that of the second transmission lines  23 .