Patent Publication Number: US-10790596-B2

Title: Smart antenna assembly

Description:
FIELD OF THE PRESENT DISCLOSURE 
     The present disclosure relates to an antenna, and more particularly to a smart antenna assembly. 
     CROSS-REFERENCE TO RELATED PATENT APPLICATION 
     This application claims the benefit of priority to Taiwan Patent Application No. 107108094, filed on Mar. 9, 2018. The entire content of the above identified application is incorporated herein by reference. 
     BACKGROUND OF THE PRESENT DISCLOSURE 
     At present, antennas used in ordinary network/communication products, for example, dipole antennas, usually have omnidirectional radiation patterns. However, when a position of such a product is fixed, signal transmission and reception can only rely on fixed radiation, which results in poor signal performance and reduced transmission speed. 
     In addition, a conventional antenna design uses multiple fixed-position antennas to control an overall radiation pattern. However, this approach has met considerable design limitations due to space constraints and cost considerations. 
     Further, a conventional antenna has only one polarization direction, for example, a horizontal polarization direction or a vertical polarization direction. Therefore, antenna signals cannot be transmitted effectively. 
     SUMMARY OF THE PRESENT DISCLOSURE 
     In response to the above-referenced technical inadequacies, the present disclosure provides a smart antenna assembly. 
     In certain aspects, the present disclosure provides an antenna assembly including a first antenna device. The first antenna device includes a first polarization antenna, a second polarization antenna, a first switch unit, a first control terminal and a second control terminal. The first polarization antenna includes a first antenna, a first reflection element disposed on a first side of the first antenna, and a second reflection element disposed on a second side of the first antenna. The second polarization antenna includes a second antenna, a third reflection element disposed on a third side of the second antenna, and a fourth reflection element disposed on a fourth side of the second antenna. The first switch unit includes a first switch element electrically connected to the first reflection element, a second switch element electrically connected to the second reflection element, a third switch element electrically connected to the third reflection element, and a fourth switch element electrically connected to the fourth reflection element. The first control terminal is used for turning on the first switch element and the third switch element. The second control terminal is used for turning on the second switch element and the fourth switch element. 
     One of the beneficial effects of the present disclosure is that, through the technical features of “the first control terminal is used to turn on the first switch element and the third switch element, and the second control terminal is used to turn on the second switch element and the fourth switch element,” the smart antenna assembly can change its radiation pattern. 
     These and other aspects of the present disclosure will become apparent from the following description of the embodiment taken in conjunction with the following drawings and their captions, although variations and modifications therein can be affected without departing from the spirit and scope of the novel concepts of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure will become more fully understood from the detailed description and the accompanying drawings, in which: 
         FIG. 1  is a schematic diagram of a first smart antenna device of a smart antenna assembly according to an embodiment of the present disclosure. 
         FIG. 2  is a schematic diagram of the first smart antenna device of the smart antenna assembly implemented on a substrate according to an embodiment of the present disclosure. 
         FIG. 3  is a perspective assembled view of the first smart antenna device of the smart antenna assembly according to an embodiment of the present disclosure. 
         FIG. 4  is a perspective exploded view of the first smart antenna device of the smart antenna assembly according to an embodiment of the present disclosure. 
         FIG. 5  is a functional block diagram of the smart antenna assembly according to an embodiment of the present disclosure. 
         FIG. 6  is another functional block diagram of the smart antenna assembly according to an embodiment of the present disclosure. 
         FIG. 7A  is a schematic radiation pattern diagram of a first polarization antenna when each of first to fourth switch elements is in a non-conducting state. 
         FIG. 7B  is a schematic radiation pattern diagram of a second polarization antenna when each of the first to fourth switch elements is in a non-conducting state. 
         FIG. 8A  is a schematic radiation pattern diagram of the first polarization antenna when the first and third switch elements are in a conducting state, and the second and fourth switch elements are in a non-conducting state. 
         FIG. 8B  is a schematic radiation pattern diagram of the second polarization antenna when the first and third switch elements are in a conducting state, and the second and fourth switch elements are in a non-conducting state. 
         FIG. 9A  is a schematic radiation pattern diagram of the first polarization antenna when the second and fourth switch elements are in a conducting state, and the first and third switch elements are in a non-conducting state. 
         FIG. 9B  is a schematic radiation pattern diagram of the second polarization antenna when the second and fourth switch elements are in a conducting state, and the first and third switch elements are in a non-conducting state. 
         FIG. 10  is a schematic diagram of a second smart antenna device of the smart antenna assembly according to one embodiment of the present disclosure. 
         FIG. 11  is a perspective assembled view of the second smart antenna device of the smart antenna assembly according to one embodiment of the present disclosure. 
         FIG. 12  is a perspective exploded view of the second smart antenna device of the smart antenna assembly according to one embodiment of the present disclosure. 
         FIG. 13  is a schematic perspective view of the first smart antenna device and the second smart antenna device arranged adjacent to each other according to an embodiment of the present disclosure. 
         FIG. 14  is a functional block diagram of the smart antenna assembly according to an embodiment of the present disclosure. 
         FIG. 15A  is a schematic radiation pattern diagram of the first polarization antenna. 
         FIG. 15B  is a schematic radiation pattern diagram of the second polarization antenna. 
         FIG. 16A  is a schematic radiation pattern diagram of the third polarization antenna. 
         FIG. 16B  is a schematic radiation pattern diagram of the fourth polarization antenna. 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS 
     The present disclosure is more particularly described in the following examples that are intended as illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. Various embodiments of the present disclosure are now described in detail. Referring to the drawings, like numbers, if any, indicate like components throughout the views. As used in the description herein and throughout the claims that follow, the meaning of “a”, “an”, and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein and throughout the claims that follow, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise. Moreover, titles or subtitles can be used in the specification for the convenience of a reader, which shall have no influence on the scope of the present disclosure. Additionally, some terms used in this specification are more specifically defined below. 
     The terms used in this specification generally have their ordinary meanings in the art, within the context of the present disclosure, and in the specific context where each term is used. Certain terms that are used to describe the present disclosure are discussed below, or elsewhere in the specification, to provide additional guidance to the practitioner regarding the description of the present disclosure. For convenience, certain terms can be highlighted, for example using italics and/or quotation marks. The use of highlighting has no influence on the scope and meaning of a term; the scope and meaning of a term is the same, in the same context, whether or not it is highlighted. It will be appreciated that the same thing can be expressed in more than one way. Consequently, alternative language and synonyms can be used for any one or more of the terms discussed herein, and no special significance is to be placed upon whether or not a term is elaborated or discussed herein. Synonyms for certain terms can be provided. A recital of one or more synonyms does not exclude the use of other synonyms. The use of examples anywhere in this specification including examples of any terms discussed herein is illustrative only, and in no way limits the scope and meaning of the present disclosure or of any exemplified term. Likewise, the present disclosure is not limited to various embodiments given in this specification. 
     Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. In the case of conflict, the present document, including any definitions given herein, will prevail. 
     While numbering terms such as “first”, “second” or “third” can be used in this disclosure to describe various components, signals or the like, the terms are for distinguishing one component from another component, or one signal from another signal only, and are not intended to, nor should they be construed to impose any other substantive descriptive limitations on the components, signals or the like. 
     First, reference is made to  FIG. 1 , which is a schematic diagram of a first smart antenna device of a smart antenna assembly according to an embodiment of the present disclosure. It should be noted that the smart antenna assembly A of the present disclosure can preferably include a first smart antenna device  1  and a second smart antenna device  2  (as shown in  FIG. 13 ). Nevertheless, a smart antenna assembly A including only the first smart antenna device  1 , that is, without the second smart antenna device  2 , can still be implemented. The embodiment(s) in which the smart antenna assembly A includes a first smart antenna device  1  are described as follows. 
     Referring again to  FIG. 1 , the present disclosure provides a smart antenna assembly A, which includes a first smart antenna device  1 . The first smart antenna device  1  can include a first polarization antenna  11 , a second polarization antenna  12 , a first switch unit  13 , a first control terminal P 1  and a second control terminal P 2 . For example, the polarization direction of the first polarization antenna  11  and the polarization direction of the second polarization antenna  12  are different from each other. In certain embodiments, the polarization directions of the first polarization antenna  11  and the second polarization antenna  12  are substantially orthogonal to each other. In addition, in one embodiment, the first polarization antenna  11  can be a horizontal polarization antenna, and the second polarization antenna  12  can be a vertical polarization antenna. However, the present disclosure is not limited thereto. In certain embodiments, referring again to  FIG. 1 , the first polarization antenna  11  can include a first antenna  111 , a first reflection element  112  disposed on a first side (for example, the right side) of the first antenna  111 , and a second reflection element  113  disposed on a second side (for example, the left side) of the first antenna  111 . The second polarization antenna  12  can include a second antenna  121 , a third reflection element  122  disposed on a third side (for example, the right side) of the second antenna  121 , and a fourth reflection element  123  disposed on a fourth side (for example, the left side) of the second antenna  121 . For example, the first antenna  111  and the second antenna  121  can be collectively implemented by a dipole antenna. The first antenna  111  and the second antenna  121  can generate at least one operating frequency band, and the frequency range of the operating frequency band can be between 5150 MHz and 5850 MHz, so that the first smart antenna device  1  is operable within the 5G Wireless Local Area Network (WLAN) band. However, the present disclosure is not limited thereto. In other embodiments, the smart antenna assembly A can be a dual-frequency (2.4G/5G) dual-polarization antenna. That is, each of the first antenna  111  and the second antenna  121  has two operating frequency bands, for example, an operating frequency band between 5150 MHz and 5850 MHz, and an operating frequency band between 2400 MHz and 2500 MHz. However, the present disclosure is not limited thereto. In addition, it should be noted that in the following embodiments, the first antenna  111  and the second antenna  121  with operating frequency band ranges between 5150 MHz and 5850 MHz are provided as examples and for illustration purpose only. 
     In certain embodiments, referring again to  FIG. 1 , the first reflection element  112  and the second reflection element  113  can be respectively disposed in parallel on two opposite sides (for example, the right and left sides) of the first antenna  111 . The third reflection element  122  and the fourth reflection element  123  can be respectively disposed in parallel on opposite sides (for example, the right side and left side) of the second antenna  121 . In this way, the radiation pattern of the first antenna  111  can be changed by conducting one of the first reflection element  112  and the second reflection element  113 . And the radiation pattern of the second antenna  121  can be changed by conducting one of the third reflection element  122  and the fourth reflection element  123 . The details of the radiation pattern changes are specified in the following embodiments. 
     In certain embodiments, referring again to  FIG. 1 , preferably, the distance between the first reflection element  112  and the first antenna  111  is between one-eighth and one-fourth of the wavelength of the operating frequency of the first antenna  111 , that is, between 0.125λ and 0.25λ. The distance between the second reflection element  113  and the first antenna  111  is between one-eighth and one-fourth of the wavelength of the operating frequency of the first antenna  111 , that is, between 0.125λ and 0.25λ. The distance between the third reflection element  122  and the second antenna  121  is between one-eighth and one-fourth of the wavelength of the operating frequency of the second antenna  121 , that is, between 0.125λ and 0.25λ. The distance between the fourth reflection element  123  and the second antenna  121  is between one-eighth and one-fourth of the wavelength of the operating frequency of the second antenna  121 , that is, between 0.125λ and 0.25λ. In certain embodiments, the above-referenced operating frequency can be the center frequency of the operating frequency band of the smart antenna assembly A. However, the present disclosure is not limited thereto. In certain embodiments, when the antenna(s) of the smart antenna assembly A is a dual-frequency dual-polarization antenna, the center frequency of a higher operating frequency band supported by the smart antenna assembly A can be selected as the operating frequency of the smart antenna assembly A. Therefore, the distances between the first antenna  111  and the reflection elements are shorter, so that the overall volume of the smart antenna assembly A is reduced. In other words, when the first polarization antenna  11  supports a first operating frequency band and a second operating frequency band, the second polarization antenna  12  supports a third operating frequency band and a fourth operating frequency band, the center frequency of the first operating frequency band is higher than the center frequency of the second operating frequency band, and the center frequency of the third operating frequency band is higher than the center frequency of the fourth operating frequency band, the distance between the first reflection element  112  and the first antenna  111  can be between one-eighth and one-fourth of the wavelength of the center frequency of the first operating frequency band of the first antenna  111 , the distance between the second reflection element  113  and the first antenna  111  can be between one-eighth and one-fourth of the wavelength of the center frequency of the first operating frequency band of the first antenna  111 , the distance between the third reflection element  122  and the second antenna  121  can be between one-eighth and one-fourth of the wavelength of the center frequency of the third operating frequency band of the second antenna  121 , and the distance between the fourth reflection element  123  and the second antenna  121  can be between one-eighth and one-fourth of the wavelength of the center frequency of the third operating frequency band of the second antenna  121 . In certain embodiments, more preferably, the distance between the first reflection element  112  and the first antenna  111  is the same as the distance between the second reflection element  123  and the first antenna  111 . And the distance between the third reflection element  122  and the second antenna  121  is the same as the distance between the fourth reflection element  123  and the second antenna  121 . In certain embodiments, the first operating frequency band is the same as the third operating frequency band, and the second operating frequency band is the same as the fourth operating frequency band. However, the present disclosure is not limited thereto. 
     In certain embodiments, referring again to  FIG. 1 , the first switch unit  13  can include a first switch element  131  electrically connected to the first reflection element  112 , a second switch element  132  electrically connected to the second reflection element  113 , a third switch element  133  electrically connected to the third reflection element  122 , and a fourth switch element  134  electrically connected to the fourth reflection element  123 . For example, at least one of the first switch element  131 , the second switch element  132 , the third switch element  133  and the fourth switch element  134  can be a diode or a metal-oxygen-semiconductor field-effect transistor (MOSFET). However, the present disclosure is not limited thereto. In certain embodiments, other types of unidirectional switch elements can also be used. In addition, it should be noted that, the first switch element  131 , the second switch element  132 , the third switch element  133  and the fourth switch element  134  can be respectively connected in series to the conducting path of the first reflection element  112 , the conducting path of the second reflection element  113 , the conducting path of the third reflection element  122 , and the conducting path of the fourth reflection element  123 . Thereby, the first switch element  131 , the second switch element  132 , the third switch element  133  and the fourth switch element  134  can be used to respectively control the conducting of the first reflection element  112 , the second reflection element  113 , the third reflection element  122  and the four reflection elements  123 . 
     In certain embodiments, referring again to  FIG. 1 , one of the first control terminal P 1  and the second control terminal P 2  can output a first direct current (DC) signal. In certain embodiments, for example, the first control terminal P 1  can be electrically connected to the first reflection element  112  and the third reflection element  122 , and the second control terminal P 2  can be electrically connected to the second reflection element  113  and the fourth reflection element.  123 . Thereby, the first direct current signal can be inputted into the first reflection element  112  and the third reflection element  122  at the same time, or be inputted into the second reflection element  113  and the fourth reflection element  123  at the same time. It should be noted that, when the first control terminal P 1  and the second control terminal P 2  are directly electrically connected to diodes, each reflection element will become a director. Therefore, preferably, the first control terminal P 1  and the second control terminal P 2  are indirectly electrically connected to the diodes through the reflection elements. 
     In certain embodiments, when the first control terminal P 1  outputs the first direct current signal, the first control terminal P 1  can be used to turn on the first switch element  131  and the third switch element  133 . When the second control terminal P 2  outputs the first direct current signal, the second control terminal P 2  can be used to turn on the second switch element  132  and the fourth switch element  134 . In this way, the first reflection element  112  and the third reflection element  122 , or the second reflection element  113  and the fourth reflection element  123  can be selectively configured to be conductive at the same time, so as to control the radiation pattern of the first antenna  111  and the second antenna  121 . 
     Reference is made again to  FIG. 1 , and also to  FIG. 2  to  FIG. 4 .  FIG. 2  is a schematic diagram of the first smart antenna device  1  of the smart antenna assembly A implemented on a substrate according to an embodiment of the present disclosure.  FIG. 3  is a perspective assembled view of the first smart antenna device  1  of the smart antenna assembly A according to an embodiment of the present disclosure.  FIG. 4  is a perspective exploded view of the first smart antenna device  1  of the smart antenna assembly A according to an embodiment of the present disclosure. Specifically, the smart antenna assembly A can further include a first substrate  11 S and a second substrate  12 S. The first polarization antenna  11  can be disposed on the first substrate  11 S, and the second polarization antenna  12  can be disposed on the second substrate  12 S. The first substrate  11 S and the second substrate  12 S are arranged substantially perpendicular to each other. In certain embodiments, a first predetermined included angle θ 1  between the first substrate  11 S and the second substrate  12 S is between 80 degrees and 100 degrees. It should be noted that, when the first substrate  11 S and the second substrate  12 S are arranged substantially perpendicular to each other, an antenna isolation can be maximized, so as to reduce radiation signal interference. In certain embodiments, each of the first substrate  11 S and the second substrate  12 S can be a microwave substrate. The microwave substrate can be, for example, a printed circuit board (PCB). The first polarization antenna  11  and the polarization antennas  12  can be fabricated respectively on the first substrate  11 S and the second substrate  12 S by using etching techniques. However, the present disclosure is not limited thereto. 
     Referring again to  FIG. 1  and  FIG. 2 , in certain embodiments, the first reflection element  112  can include a first section  1121  and a second section  1122 . The first switch element  131  can be electrically connected between the first section  1121  and the second section  1122 . The second reflection element  113  can include a third section  1131  and a fourth section  1132 . The second switch element  132  can be electrically connected between the third section  1131  and the fourth section  1132 . The third reflection element  122  can include a fifth section  1221  and a sixth section  1222 . The third switch element  133  can be electrically connected between the fifth section  1221  and the sixth section  1222 . The fourth reflection element  123  can include a seventh section  1231  and an eighth section  1232 . The fourth switch element  134  can be electrically connected between the seventh section  1231  and the eighth section  1232 . It is also noted that any following embodiments of the present disclosure with each of the first, second, third and fourth switch elements  131  to  134  being a diode are provided for illustration purpose only. 
     Referring again to  FIG. 1  and  FIG. 2 , the first control terminal P 1  can be electrically connected to the first section  1121  of the first reflection element  112 . The first section  1121  of the first reflection element  112  can be electrically connected to the anode of the diode  131 . The cathode of the diode  131  can be electrically connected to the second section  1122  of the first reflection element  112 . The first section  1121  of the first reflection element  112  can be electrically connected to the fifth section  1221  of the third reflection element  122 . The fifth section  1221  of the third reflection element  122  can be electrically connected to the anode of the diode  133 . The cathode of the diode  133  can be electrically connected to the sixth section  1222  of the third reflection element  122 . In addition, it is worth noting that the second section  1122  of the first reflection element  112  and the sixth section  1222  of the third reflection element  122  can be electrically connected to ground. Further, the second control terminal P 2  can be electrically connected to the third section  1131  of the second reflection element  113 , and the third section  1131  of the second reflection element  113  can be electrically connected to the anode of the diode  132 . The cathode of the diode  132  can be electrically connected to the fourth section  1132  of the second reflection element  113 . The third section  1131  of the second reflection element  113  can be electrically connected to the seventh section  1231  of the fourth reflection element  123 . The seventh section  1231  of the fourth reflection element  123  can be electrically connected to the anode of the diode  134 . The cathode of the diode  134  can be electrically connected to the eighth section  1232  of the fourth reflection element  123 . In addition, it is worth noting that the fourth section  1132  of the second reflection element  113  and the eighth section  1232  of the fourth reflection element  123  can be electrically connected to ground. Further, it is also worth noting that when the first polarization antenna  11  and the second polarization antenna  12  are respectively disposed on the first substrate  11 S and the second substrate  12 S, via holes V or other kinds of conducting sheets can be used so that the first section  1121  of the first reflection element  112  is electrically connected to the fifth section  1221  of the third reflection element  122 , and that the third section  1131  of the second reflection element  113  can be electrically connected to the seventh section  1231  of the fourth reflection element  123 . However, the present disclosure is not limited thereto. 
     Referring again to  FIG. 1  and  FIG. 2 , the first antenna  111  can further include a first radiating portion  1111 , a second radiating portion  1112 , and a first feeding element  1113  for receiving a first radio frequency (RF) signal. The first feeding element  1113  can have a first signal feeding terminal F 1  and a first ground terminal F 2 . The first signal feeding terminal F 1  can be electrically connected to the first radiating portion  1111 . The first ground terminal F 2  can be electrically connected to the second radiating portion  1112 . The second radiating portion  1112  can be electrically connected to the second section  1122  of the first reflection element  112  and the fourth section  1132  of the second reflection element  113 . In certain embodiments, as shown in  FIG. 1  and  FIG. 2 , the first feeding element  1113  can be a first coaxial cable  1113 ′. The first coaxial cable  1113 ′ can have the first signal feeding terminal F 1  and the first ground terminal F 2 . Therefore, the first coaxial cable  1113 ′ can be used to feed the first radio frequency signal to the first antenna  111 . In addition, it should be noted that, in order to make the figures of the present disclosure easily understandable, the first feeding element  1113  in  FIG. 1  is represented by an alternative symbol to indicate the structure of the coaxial cable shown in  FIG. 2 , as well as the electrical connection configuration of the signal transmission therein. However, the present disclosure is not limited thereto. 
     Referring again to  FIG. 1  and  FIG. 2 , the second antenna  121  can further include a third radiating portion  1211 , a fourth radiating portion  1212 , and a second feeding element  1213  for receiving a second radio frequency signal. The second feeding element  1213  can have a second signal feeding terminal F 3  and a second ground terminal F 4 . The second signal feeding terminal F 3  can be electrically connected to the third radiating portion  1211 , and the second ground terminal F 4  can be electrically connected to the fourth radiating portion  1212 . The fourth radiating portion  1212  is electrically connected to the sixth section  1222  of the third reflection element  122  and the eighth section  1232  of the fourth reflection element  123 . In certain embodiments, as shown in  FIG. 1  and  FIG. 2 , the second feeding element  1213  can be a second coaxial cable line  1213 ′. The second coaxial cable  1213 ′ can have the second signal feeding terminal F 3  and the second ground terminal F 4 . Therefore, the second coaxial cable  1213 ′ can be used to feed the second radio frequency signal to the second antenna  121 . 
     Referring again to  FIG. 1  and  FIG. 2 , in certain embodiments, the second section  1122  of the first reflection element  112  and the fourth section  1132  of the second reflection element  113  can share a common ground with the second radiating portion  1112  of the first antenna  111 . The sixth section  1222  of the third reflection element  122  and the eighth section  1232  of the fourth reflection element  123  can share a common ground with the fourth radiating portion  1212  of the second antenna  121 . Therefore, the second section  1122  of the first reflection element  112  and the fourth section  1132  of the second reflection element  113  can be electrically connected to the second radiating portion  1112  of the first antenna  111 . Further, the sixth section  1222  of the third reflection element  122  and the eighth section  1232  of the fourth reflection element  123  can be electrically connected to the fourth radiating section  1212  of the second antenna  121 . However, the present disclosure is not limited thereto. 
     Further, referring again to  FIG. 1  and  FIG. 2 , in certain embodiments, the first smart antenna device  1  can further include a first radio frequency choke unit  14  electrically connected between the second section  1122  of the first reflection element  112  and the second radiating portion  1112  of the first antenna  111 , a second radio frequency choke unit  15  electrically connected between the fourth section  1132  of the second reflection element  113  and the second radiating portion  1112  of the first antenna  111 , a third radio frequency choke unit  16  electrically connected between the sixth section  1222  of the third reflection element  122  and the fourth radiating portion  1212  of the second antenna  121 , and a fourth radio frequency choke unit  17  electronically connected between the eighth section  1232  of the fourth reflection element  123  and the fourth radiating section  1212  of the second antenna  121 , so as to filter noise and protect the diodes  131  to  134 . 
     Further, referring again to  FIG. 1  to  FIG. 4 , the first radio frequency choke unit  14 , the second radio frequency choke unit  15 , the third radio frequency choke unit  16  and the fourth radio frequency choke unit  17  can be surface-mount devices (SMD), and can be respectively connected to the first substrate  11 S and the second substrate  12 S through surface-mounting processes. However, the present disclosure is not limited thereto. In certain embodiments, the first radio frequency choke unit  14  can include a first radio frequency choke element  141  and a second radio frequency choke element  142  connected in series with each other. The first radio frequency choke element  141  and the second radio frequency choke element  142  can be connected by a wire (not labeled in the figures) disposed between the first radio frequency choke element  141  and the second radio frequency choke element  142 . The first radio frequency choke element  141  can be electrically connected to the second section  1122  of the first reflection element  112 . The second radio frequency choke element  142  can be electrically connected to the second radiating portion  1112  of the first antenna  111 . Preferably, the first radio frequency choke element  141  can abut against an edge of the second section  1122  of the first reflection element  112 , and the second radio frequency choke element  142  can abut against an edge of the second radiating portion  1112  of the first antenna  111 . Further, the second radio frequency choke unit  15  can include a third radio frequency choke element  151  and a fourth radio frequency choke element  152  connected in series with each other. The third radio frequency choke element  151  and the fourth radio frequency choke element  152  can be connected by a wire (not labeled in the figure) disposed between the third radio frequency choke element  151  and the fourth radio frequency choke element  152 . The third radio frequency choke element  151  can be electrically connected to the fourth section  1132  of the second reflection element  113 . The fourth radio frequency choke element  152  can be electrically connected to the second radiating portion  1112  of the first antenna  111 . Preferably, the third radio frequency choke element  151  can abut against an edge of the fourth section  1132  of the second reflection element  113 , and the fourth radio frequency choke element  152  can abut against an edge of the second radiating portion  1112  of the first antenna  111 . Further, the third radio frequency choke unit  16  can include a fifth radio frequency choke element  161  and a sixth radio frequency choke element  162  connected in series with each other. The fifth radio frequency choke element  161  and the sixth radio frequency choke element  162  can be connected by a wire (not labeled in the figure) disposed between the fifth radio frequency choke element  161  and the sixth radio frequency choke element  162 . The radio frequency choke element  161  can be electrically connected to the sixth section  1222  of the third reflection element  122 , and the sixth radio frequency choke element  162  can be electrically connected to the fourth radiating portion  1212  of the second antenna  121 . Preferably, the fifth radio frequency choke element  161  can abut against an edge of the sixth section  1222  of the third reflection element  122 , and the sixth radio frequency choke element  162  can abut against an edge of the fourth radiation part  1212  of the second antenna  121 . Further, the fourth radio frequency choke unit  17  can include a seventh radio frequency choke element  171  and an eighth radio frequency choke element  172  connected in series with each other. The seventh radio frequency choke element  171  and the eighth radio frequency choke element  172  can be connected by a wire (not labeled in the figure) disposed between the seventh radio frequency choke element  171  and the eighth radio frequency choke element  172 . The seventh radio frequency choke element  171  can be electrically connected to the eighth section  1232  of the fourth reflection element  123 . The eighth radio frequency choke element  172  can be electrically connected to the fourth radiation part  1212  of the second antenna  121 . Preferably, the seventh radio frequency choke element  171  can abut against an edge of the eighth section  1232  of the fourth reflection element  123 , and the eighth radio frequency choke element  172  can abut against an edge of the fourth radiation part  1212  of the second antenna  121 . Thereby, the technical features of radio frequency choke elements abutting against adjacent reflection elements (the first reflection element  112 , the second reflection element  113 , the third reflection element  122  and the fourth reflection element  123 ) and abutting against adjacent antenna elements (the first antenna  111  and the second antenna  121 ) can prevent the antenna elements (the first antenna  111  and the second antenna  121 ) from generating stubs affecting antenna resonant frequencies and impedance matchings. Further, the technical feature can also prevent reflection elements (the first reflection element  112 , the second reflection element  113 , the third reflection element  122  and the fourth reflection element  123 ) from generating stubs affecting antenna pattern switching performance, that is, antenna gain. 
     In certain embodiments, as shown in  FIG. 1  and  FIG. 2 , the radio frequency choke elements  151 ,  152 ,  161 ,  162 ,  171 ,  172 ,  181  and  182  can be inductors. However, the present disclosure is not limited thereto. Further, preferably, for the purpose of further filtering noise, choke elements L can be disposed between the first control terminal P 1  and the first section  1121  of the first reflection element  112 , and between the second control terminal P 2  and the third section  1131  of the second reflection element  113 . Further, choke elements L can also be disposed between the first section  1121  of the first reflection element  112  and the fifth section  1221  of the third reflection element  122 , and between the third section  1131  of the second reflection element  113  and the seventh section  1231  of the fourth reflection element  123 . In certain embodiments, a choke element L can be an inductor. However, the present disclosure is not limited thereto. 
     Next, referring again to  FIG. 1 , details of radiation pattern change is further described as follows. One of the first control terminal P 1  and the second control terminal P 2  can output a first direct current signal. In certain embodiments, when the first direct current signal causes the diodes  131  to  134  to be non-conducting, the first antenna  111  and the second antenna has substantially omnidirectional radiation. When the diode  131  and the diode  133  are conducted and the diode  132  and the diode  134  are not conducted, the radiation patterns of the first antenna  111  and the second antenna  121  can be changed to be one radiating toward a first direction (for example, a left direction). Further, when the diode  132  and the diode  134  of the first smart antenna device  1  are conducted, and the diode  131  and the diode  133  are not conducted, the radiation patterns of the first antenna  111  and the second antenna  121  can be changed to be one radiating toward a second direction (for example, a right direction). 
     Furthermore, it is worth noting that the smart antenna assembly A can further include a first reflection structure R 1  and a second reflection structure R 2 . The first reflection structure R 1  can be disposed on one side (for example, an upper side) of the second antenna  121 , and the second reflection structure R 2  can be disposed on the other side (for example, the lower side) of the second antenna  121 . In this way, the gain of the first smart antenna device  1  of the smart antenna assembly A can be adjusted, and a radiation pattern can be compressed. 
     Next, reference is made to  FIG. 5 .  FIG. 5  is a functional block diagram of a smart antenna assembly A according to an embodiment of the present disclosure. The smart antenna assembly A can further include a switching circuit  4  and a radio frequency circuit  3 . The radio frequency circuit  3  can be electrically connected to the switching circuit  4  to transmit a control signal to the switching circuit  4 . Further, the radio frequency circuit  3  can also be electrically connected to the first smart antenna device  1  to transmit the first direct current signal to one of the first control terminal P 1  and the second control terminal P 2 . In certain embodiments, the switching circuit  4  can be electrically connected to the feed receiving elements of the first polarization antenna  11  and the second polarization antenna  12 . The switching circuit  4  can select one of the first polarization antenna  11  and the second antennas  12  according to the control signal, so as to transmit a first radio frequency signal of the radio frequency circuit  3  to the first polarization antenna  11 , or to transmit a second radio frequency signal of the transmission radio frequency circuit  3  to the second polarization antenna  12 . In other words, by adopting the switching circuit  4 , a radio frequency signal can be selectively transmitted to one of the first polarization antenna  11  and the second polarization antenna  12 . That is, one of the first polarization antenna  11  and the second polarization antenna  12  is selectively turned on. In certain embodiments, the first polarization antenna  11  can be a horizontal polarization antenna, the second polarization antenna  12  can be a vertical polarization antenna, and the switching circuit  4  can switch polarization antennas to transmit a radio frequency to an appropriate polarization antenna for signal transmission according to the control signal. That is, the switching circuit  4  can be used to switch the polarization direction of the first smart antenna device  1 . 
     Reference is made to  FIG. 6 , which is another functional block diagram of a smart antenna assembly A according to an embodiment of the present disclosure. In certain embodiments, when the first polarization antenna  11  and the second polarization antenna  12  of the first smart antenna device  1  not only have a first/third operating frequency band between 5150 MHz and 5850 MHz, but further have a second/fourth operating frequency band between 2400 MHz and 2500 MHz, the smart antenna assembly A can further include a diplexer  5 . Further, the diplexer  5  can be electrically connected between the switching circuit  4  and the first smart antenna device  1 . The diplexer  5  can operate in the first/third operating frequency band and the second/fourth operating frequency band of the first smart antenna device  1 . The radio frequency circuit  3  can further include a radio frequency transceiver (not shown in the figure) for the first/third operating frequency band and a radio frequency transceiver (not shown in the figure) for the second/fourth operating frequency band. 
     Further, reference is made to  FIG. 7A  to  FIG. 9B .  FIG. 7A  is a schematic radiation pattern diagram of the first polarization antenna  11  when each of the first to fourth switch elements  131  to  134  is in a non-conducting state.  FIG. 7B  is a schematic radiation pattern diagram of the second polarization antenna  12  when each of the first to fourth switch elements  131  to  134  is in a non-conducting state.  FIG. 8A  is a schematic radiation pattern diagram of the first polarization antenna  11  when the first and third switch elements  131  and  133  are in a conducting state, and the second and fourth switch elements  132  and  134  are in a non-conducting state.  FIG. 8B  is a schematic radiation pattern diagram of the second polarization antenna  12  when the first and third switch elements  131  and  133  are in a conducting state, and the second and fourth switch elements  132  and  134  are in a non-conducting state.  FIG. 9A  is a schematic radiation pattern diagram of the first polarization antenna  11  when the second and fourth switch elements  132  and  134  are in a conducting state, and the first and third switch elements  131  and  133  are in a non-conducting state.  FIG. 9B  is a schematic radiation pattern diagram of the second polarization antenna  12  when the second and fourth switch elements  132  and  134  are in a conducting state, and the first and third switch elements  131  and  133  are in a non-conducting state. Embodiments in which the first polarization antenna  11  being a horizontal polarization antenna, and the second polarization antenna  12  being a vertical polarization antenna are provided as follows and for illustrative purpose only. 
     As shown in  FIG. 7A  and  FIG. 7B , when the radio frequency circuit  3  does not provide the first direct current signal to the first control terminal P 1  or the second control terminal P 2 , the first switch element  131 , the second switch element  132 , the third switch element  133  and the fourth switch element  134  are not conducted. The switching circuit  4  can select one of the first polarization antenna  11  and the second polarization antenna  12  according to the control signal from the radio frequency circuit  3 , so as to transmit a first radio frequency signal to the first polarization antenna  11 , or to transmit a second radio frequency signal to the second polarization antenna  12 , so that the radiation pattern of one of the first polarization antenna  11  and the second polarization antenna  12  can be an omnidirectional radiation. 
     As shown in  FIG. 8A  and  FIG. 8B , when the first switch element  131  and the third switch element  133  are turned on by the first control terminal P 1  to be conducted, and the switching circuit  4  selects one of the first polarization antenna  11  and the second polarization antenna  12 , the radiation pattern of the first smart antenna device  1  can be one directing toward a first direction (for example, the negative direction of the X axis). That is, the switching circuit  4  can selectively use the first polarization antenna  11  or the second polarization antenna  12  according to the control signal from the radio frequency circuit  3 , and causes the radiation pattern of the first polarization antenna  11  or the second polarization antenna  12  to be directed toward a first direction. 
     As shown in  FIG. 9A  and  FIG. 9B , when the second switch element  132  and the fourth switch element  134  are turned on by the second control terminal P 2  to be conducted, and the switching circuit  4  selects one of the first polarization antenna  11  and the second polarization antenna  12 , the radiation pattern of the first smart antenna device  1  can be one directing toward a second direction (for example, the positive direction of the X axis). That is, the switching circuit  4  can selectively use the first polarization antenna  11  or the second polarization antenna  12  according to the control signal from the radio frequency circuit  3 , and causes the radiation pattern of the first polarization antenna  11  or the second polarization antenna  12  to be directed toward a second direction. 
     Thereby, by comparing  FIG. 8A  and  FIG. 8B  with  FIG. 9A  and  FIG. 9B , it can be derived that the radio frequency circuit  3  selects one of the first control terminal P 1  and the second control terminal P 2  to output a first direct current signal, so that the first smart antenna device  1  can generate radiation patterns with opposite radiation directions, for example, the first direction (the negative direction of the X axis) and the second direction (the positive direction of the X axis) are opposite to each other. 
     Next, reference is made to  FIG. 10  to  FIG. 12 .  FIG. 10  is a schematic diagram of the second smart antenna device  2  of the smart antenna assembly A according to one embodiment of the present disclosure.  FIG. 11  is a perspective assembled view of the second smart antenna device  2  of the smart antenna assembly A according to one embodiment of the present disclosure.  FIG. 12  is a perspective exploded view of the second smart antenna device  2  of the smart antenna assembly A according to one embodiment of the present disclosure. 
     Referring again to  FIG. 10  to  FIG. 12 , the second smart antenna device  2  can include a third polarization antenna  21 , a fourth polarization antenna  22 , a second switch unit  23 , a third control terminal P 3  and a fourth control terminal P 4 . The third polarization antenna  21  can include a third antenna  211 , a fifth reflection element  212  disposed on a fifth side of the third antenna  211 , and a sixth reflection element  213  disposed on a sixth side of the third antenna  211 . The fourth polarization antenna  22  can include a fourth antenna  221 , a seventh reflection element  222  disposed on a seventh side of the fourth antenna  221 , and an eighth reflection element  223  disposed on an eighth side of the fourth antenna  221 . 
     In certain embodiments, as described above, the third antenna  211  and the fourth antenna  221  can generate at least one operating frequency band or two operating frequency bands. Preferably, the smart antenna assembly A can further include a third substrate  21 S and a fourth substrate  22 S. The third polarization antenna  21  can be disposed on the third substrate  21 S. The fourth polarization antenna  22  can be disposed on the fourth substrate  22 S. The third substrate  21 S and the fourth substrate  22 S are substantially perpendicular to each other. However, in certain embodiments, a second predetermined included angle θ 2  between the third substrate  21 S and the fourth substrate  22 S is between 80 degrees and 100 degrees. Nevertheless, the present disclosure is not limited thereto. 
     Referring again to  FIG. 10  to  FIG. 12 , the second switch unit  23  can include a fifth switch element  231  electrically connected to the fifth reflection element  212 , a sixth switch element  232  electrically connected to the sixth reflection element  213 , a seventh switch element  233  electrically connected to the seventh reflection element  222 , and an eighth switch element  234  electrically connected to the eighth reflection element  223 . At least one of the fifth switch element  231  to the eighth switch element  234  can be a diode or a MOSFET. Further, the third control terminal P 3  can be used to turn on the fifth switch element  231  and the seventh switch element  233 , and the fourth control terminal P 4  can be used to turn on the sixth switch element  232  and the eighth switch element  234 . Further, one of the third control terminal P 3  and the fourth control terminal P 4  can output a second direct current signal. 
     Referring again to  FIG. 10  to  FIG. 12 , in certain embodiments, the third control terminal P 3  can be electrically connected to the fifth reflection element  212  and the seventh reflection element  222 , and the fourth control terminal P 4  can be electrically connected to the sixth reflection element  213  and the eighth reflection element  223 . Thereby, the fifth reflection element  212  and the seventh reflection element  222  can be inputted with the second direct current signal at the same time, or the sixth reflection element  213  and the eighth reflection element  223  can be inputted with the second direct current signal at the same time. When the third control terminal P 3  outputs the second direct current signal, the third control terminal P 3  can be used to turn on the fifth switch element  231  and the seventh switch element  233 . When the fourth control terminal P 4  outputs the second direct current signal, the fourth control terminal P 4  can be used to turn on the sixth switch element  232  and the eighth switch element  234 . In this way, the fifth reflection element  212  and the seventh reflection element  222 , or the sixth reflection element  213  and the eighth reflection element  223 , can be selectively conducted at the same time, so as to control the radiation patterns of the third antenna  211  and the fourth antenna  221 . In certain embodiments, when the fifth switch element  231  and the seventh switch element  233  are turned on by the third control terminal P 3 , and the switching circuit  4  selects either the third polarization antenna  21  or the fourth polarization antenna  22 , the radiation pattern of the second smart antenna device  2  is one directing toward a third direction (the positive direction of the Y axis). When the sixth switch element  232  and the eighth switch element  234  are turned on by the fourth control terminal P 4 , and the switching circuit  4  selects either the third polarization antenna  21  or the fourth polarization antenna  22 , the radiation pattern of the second smart antenna device  2  is one directing toward a fourth direction (the negative direction of the Y axis). In certain embodiments, the third direction and the fourth direction are opposite to each other. In addition, it is worth noting that the radiation patterns generated by the second smart antenna device  2 , which direct toward the third direction and the fourth direction, are preferably different from the radiation patterns generated by the first smart antenna device  1 , which direct toward the first direction and the second direction. That is, the first direction (for example, the negative direction of the X axis), the second direction (for example, the positive direction of the X axis), the third direction (for example, the positive direction of the Y axis) and the fourth direction (for example, the negative direction of the Y axis) are different from each other. In certain embodiments, the first direction and the second direction are substantially perpendicular to the third direction and the fourth direction. In addition, embodiments of each of the fifth, sixth, seventh and eighth switch elements  231 - 234  being a diode as described herein serve as examples for illustrative purpose only. 
     Referring again to  FIGS. 10 to 12 , the fifth reflection element  212  can include a ninth section  2121  and a tenth section  2122 . The diode  231  can be electrically connected between the ninth section  2121  and the tenth section  2122 . The sixth reflection element can include an eleventh section  2131  and a twelfth section  2132 . The diode  232  can be electrically connected between the eleventh section  2131  and the twelfth section  2132 . The seventh reflection element  222  can include a thirteenth section  2221  and a fourteenth section  2222 . The diode  233  can be electrically connected between the thirteenth section  2221  and the fourteenth section  2222 . The eighth reflection element  223  can include a fifteenth section  2231  and a sixteenth section  2232 . The diode  234  can be electrically connected between the fifteenth section  2231  and the sixteenth section  2232 . The third control terminal P 3  can be electrically connected to the ninth section  2121  of the fifth reflection element  212 . The ninth section  2121  of the fifth reflection element  212  can be electrically connected to the anode of the diode  231 . The cathode of the diode  231  can be electrically connected to the tenth section  2122  of the fifth reflection element  212 . The ninth section  2121  of the fifth reflection element  212  is electrically connected to the thirteenth section  2221  of the seventh reflection element  222 . The thirteenth section  2221  of the seventh reflection element  222  is electrically connected to the anode of the diode  233 . The cathode of the diode  133  is electrically connected to the fourteenth section  2222  of the seventh reflection element  222 . The fourth control terminal P 4  is electrically connected to the eleventh section  2131  of the sixth reflection element  213 . The eleventh section  2131  of the sixth reflection element  213  is electrically connected to the anode of the diode  232 . The cathode of the diode  232  is electrically connected to the twelfth section  2132  of the sixth reflection element  213 . The eleventh section  2131  of the sixth reflection element  213  is electrically connected to the fifteenth section  2231  of the eighth reflection element  223 . The fifteenth section  2231  of the eighth reflection element  223  is electrically connected to the anode of the diode  234 . The cathode of the diode  234  is electrically connected to the sixteenth section  2232  of the eighth reflection element  223 . 
     Further, as shown in  FIG. 10 , the third antenna  211  can further include a fifth radiating portion  2111 , a sixth radiating portion  2112 , and a third feeding element  2113  for receiving a third radio frequency signal. The third feeding element  2113  can have a third signal feeding terminal F 5  and a third ground terminal F 6 . The third signal feeding terminal F 5  can be electrically connected to the fifth radiating portion  2111 . The third ground terminal F 6  can be electrically connected to the sixth radiating portion  2112 . The sixth radiating portion  2112  is electrically connected to the tenth section  2122  of the fifth reflection element  212  and the twelfth section  2132  of the sixth reflection element  213 . The fourth antenna  221  can further include a seventh radiating portion  2211 , an eighth radiating portion  2212 , and a fourth feeding element  2213  for receiving a fourth radio frequency signal. The fourth feeding element  2213  can have a fourth signal feeding terminal F 7  and a fourth ground terminal F 8 . The fourth signal feeding terminal F 7  can be electrically connected to the seventh radiating portion  2211 . The fourth ground terminal F 8  can be electrically connected to the eighth radiating portion  2212 . The eighth radiating portion  2212  is electrically connected to the fourteenth section  2222  of the seventh reflection element  222  and the sixteenth section  2232  of the eighth reflection element  223 . In addition, in  FIG. 10 , an alternative symbol is used to represent the structure of the coaxial cable, so as to indicate the electrical connection configuration of the signal transmission. However, the present disclosure is not limited thereto. 
     In certain embodiments, as shown in  FIG. 10 , the second smart antenna device  2  can also include a fifth radio frequency choke unit  24 , a sixth radio frequency choke unit  25 , a seventh radio frequency choke unit  26  and an eighth radio frequency choke unit  27 . The functions and effects of such are similar to the afore-mentioned first radio frequency choke unit  14 , second radio frequency choke unit  15 , third radio frequency choke unit  16  and fourth radio frequency choke unit  17 , and therefore are not described herein. It should be noted that although a schematic diagram of the second smart antenna device  2  being implemented on a substrate is not shown in the drawings, such an implementation can be similar to that shown in  FIG. 2 , differing only in element labels. 
     Referring again to  FIGS. 11 and 12 , it is worth noting that the smart antenna assembly A can further include a third reflection structure R 3  and a fourth reflection structure R 4 . The third reflection structure R 3  can be disposed on one side (for example, an upper side) of the fourth antenna  221 , and the fourth reflection structure R 4  can be disposed on the other side (for example, the lower side) of the fourth antenna  221 . In this way, the gain of the second smart antenna device  2  of the smart antenna assembly A can be adjusted, and a radiation pattern can be compressed. 
     Next, referring to  FIG. 13 , which is a schematic perspective view of a first smart antenna device  1  and a second smart antenna device  2  arranged adjacent to each other according to an embodiment of the present disclosure. In this way, by adopting the first smart antenna device  1  together with the second smart antenna device  2 , the smart antenna assembly A can generate a radiation pattern in a first direction (for example, the negative direction of the X axis), second direction (for example, the positive direction of the X axis), a third direction (for example, the positive direction of the Y axis) and a fourth direction (for example, the negative direction of the Y axis). 
     For example, the first substrate  11 S is arranged substantially parallel to the third substrate  21 S, and the second substrate  12 S and the fourth substrate  22 S are arranged substantially perpendicular to each other. In certain embodiments, preferably, the first substrate  11 S and the third substrate  21 S can be disposed on the same plane, that is, the first polarization antenna  11  and the third polarization antenna  21  are coplanar. In certain embodiments, the distance from a center of symmetry of the first smart antenna device  1  to a center of symmetry of the second smart antenna device  2  can be defined as an electrical length. The electrical length equals to a wavelength of the lowest operating frequency in the operating frequency band where the smart antenna assembly A operates. 
     Further, through the arrangement of the substrates discussed above, the polarization direction of the first polarization antenna  11  and the polarization direction of the second polarization antenna  12  are substantially orthogonal to each other, and the polarization direction of the third polarization antenna  21  and the polarization direction of the fourth polarization antenna  22  are substantially orthogonal to each other. In certain embodiments, the polarization direction of the first polarization antenna  11  and the polarization direction of the third polarization antenna  21  are substantially the same, and the polarization direction of the second polarization antenna  12  and the polarization direction of the fourth polarization antenna  22  are substantially the same. In other words, in certain embodiments, the first polarization antenna  11  and the third polarization antenna  21  can be horizontal polarization antennas, and the second polarization antenna  12  and the fourth polarization antenna  22  can be vertical polarization antennas. 
     Next, reference is made to  FIG. 14 , which is a functional block diagram of a smart antenna assembly A according to an embodiment of the present disclosure. Preferably, in certain embodiments, the smart antenna assembly A can further include a radio frequency circuit  3  and a switching circuit  4 . The radio frequency circuit  3  can be electrically connected to the switching circuit  4  to transmit a control signal to the switching circuit  4 . The switching circuit  4  can be electrically connected to the first polarization antenna  11 , the second polarization antenna  12 , the third polarization antenna  21  and the fourth polarization antenna  22 . The switching circuit  4  can select one of the first polarization antenna  11  and the second polarization antenna  12  according to the control signal to transmit a first radio frequency signal to the first polarization antenna  11 , or to transmit a second radio frequency signal to second polarization antenna  12 . Further, the switching circuit  4  can select one of the third polarization antenna  21  and the fourth polarization antenna  22  according to the control signal, so as to transmit a third radio frequency signal to the third polarization antenna  21 , or to transmit a fourth radio frequency signal to the fourth polarization antenna  22 . Further, the radio frequency circuit  3  can be electrically connected to the first smart antenna device  1  to transmit the first direct current signal to one of the first control terminal P 1  and the second control terminal P 2 . The radio frequency circuit  3  can also be electrically connected to the second smart antenna device  2  to transmit the second direct current signal to one of the third control terminal P 3  and the fourth control terminal P 4 . 
     In addition, it is worth noting that, in certain embodiments, when the third antenna  211  and the fourth antenna  221  of the second smart antenna device  2  have at least two operating frequency bands, the smart antenna assembly A can further include a diplexer (not shown in the figure). The diplexer can be electrically connected between the switching circuit  4  and the first and second smart antenna devices  1  and  2 . The diplexer can be used to switch between the operating frequency band of the first smart antenna device  1  and the operating frequency band of the second smart antenna device  2  according to the control signal. Thereby, at first, the radio frequency circuit  3  can provide a control signal, the switching circuit  4  can select the direction of polarization, and the diplexer can then activate the first smart antenna device  1  and the second smart antenna device  2  according to the control signal. And then, the direction of the radiation pattern of the smart antenna assembly A can be selected based on the inputting of the first direct current signal and the second direct current signal. Next, reference is made again to  FIGS. 1, 10, 13 and 14 , and is further made to  FIG. 15A  to  FIG. 16B .  FIG. 15A  is a schematic radiation pattern diagram of the first polarization antenna  11 .  FIG. 15B  is a schematic radiation pattern diagram of the second polarization antenna  12 .  FIG. 16A  is a schematic radiation pattern diagram of the third polarization antenna  21 .  FIG. 16B  is a schematic radiation pattern diagram of the fourth polarization antenna  22 . When none of the first to fourth switch elements  131  to  134  is conducting, the switching circuit  4  can select one of the first polarization antenna  11  and the second polarization antenna  12  according to the control signal from the radio frequency circuit  3 , so as to transmit a first radio frequency signal to the first polarization antenna  11  or to transmit a second radio frequency signal to the second polarization antenna  12 . The radiation pattern of one of the first polarization antenna  11  and the second polarization antenna  12  is an omnidirectional radiation. For example, as shown in  FIGS. 15A and 15B , the first polarization antenna  11  can generate an omnidirectional radiation pattern as delineated by the H 1 -omni line, and the second polarization antenna  12  can generate an omnidirectional radiation pattern as delineated by the V 1 -omni line. 
     Further, referring again to  FIGS. 1, 10 and 13-16B , when the first switch element  131  and the third switch element  133  are turned on by the first control terminal P 1  to be conducted, and the switching circuit  4  selects one of the first polarization antenna  11  and the second polarization antenna  12 , the radiation pattern of the first smart antenna device  1  can be one directing toward a first direction (for example, the negative direction of the X axis). For example, as shown in  FIGS. 15A and 15B , the first polarization antenna  11  can produce a radiation pattern as delineated by the H 1 -Dir 1  line, and the second polarization antenna  12  can produce a radiation pattern as delineated by the V 1 -Dir 1  line. Further, when the second switch element  132  and the fourth switch element  133  are turned on by the second control terminal P 2  to be conducted, and the switching circuit  4  selects one of the first polarization antenna  11  and the second polarization antenna  12 , the radiation pattern of the first smart antenna device  1  can be one directing toward a second direction (for example, the positive direction of the X axis). For example, as shown in  FIGS. 15A and 15B , the first polarization antenna  11  can produce a radiation pattern as delineated by the H 1 -Dir 2  line, and the second polarization antenna  12  can produce a radiation pattern as delineated by the V 1 -Dir 2  line. 
     Further, reference is made again to  FIGS. 1, 10 and 13-16B . When none of the fifth switch element  231 , sixth switch element  232 , seventh switch element  233  and eighth switch element  234  is turned on to be conducted, the switching circuit  4  can select one of the third polarization antenna  21  and the fourth polarization antenna  22  according to the control signal from the radio frequency circuit  3 , so as to transmit a third radio frequency signal to the third polarization antenna  21  or to transmit a fourth radio frequency signal to the fourth polarization antenna  22 . The radiation pattern of one of the first polarization antenna  11  and the second polarization antenna  12  is an omnidirectional radiation. For example, as shown in  FIGS. 16A and 16B , the third polarization antenna  21  can generate an omnidirectional radiation pattern as delineated by the H 2 -omni line, and the fourth polarization antenna  22  can generate an omnidirectional radiation pattern as delineated by the V 2 -omni line. 
     Further, referring again to  FIGS. 1, 10 and 13-16B , when the fifth switch element  231  and the seventh switch element  233  are turned on by the third control terminal P 3  to be conducted, and the switching circuit  4  selects one of the third polarization antenna  21  and the fourth polarization antenna  22 , the radiation pattern of the second smart antenna device  2  can be one directing toward a third direction (for example, the positive direction of the Y axis). For example, as shown in  FIGS. 16A and 16B , the third polarization antenna  21  can produce a radiation pattern as delineated by the H 2 -Dir 1  line, and the fourth polarization antenna  22  can produce a radiation pattern as delineated by the V 2 -Dir 1  line. Further, when the sixth switch element  232  and the eighth switch element  234  are turned on by the fourth control terminal P 4 , and the switching circuit  4  selects one of the third polarization antenna  21  and the fourth polarization antenna  22 , the radiation pattern of the second smart antenna device  2  can be one directing toward a fourth direction (for example, the negative direction of the Y axis). For example, as shown in  FIGS. 16A and 16B , the third polarization antenna  21  can produce a radiation pattern shown in H 2 -Dir 2  line, and the fourth polarization antenna  22  can produce a radiation pattern shown in V 2 -Dir 2  line. 
     Thereby, based on the radiation pattern diagrams in  FIGS. 15A to 16B , it can be derived that by adopting the first smart antenna device  1  together with the second smart antenna device  2 , not only a polarization direction of the smart antenna assembly A can be selected, but also four radiation patterns, each having a direction different from the directions of other radiation patterns, can be produced. In other words, in certain embodiments, the first smart antenna device  1  can produce a horizontal polarization direction, and the second smart antenna device  2  can produce a vertical polarization direction. In certain embodiments, the first smart antenna device  1  can produce a vertical polarization direction, and the second smart antenna device  2  can produce a horizontal polarization direction. In certain embodiments, the first smart antenna device  1  can produce a horizontal polarization direction, and the second smart antenna device  2  can produce a horizontal polarization direction. In certain embodiments, the first smart antenna device  1  can produce a vertical polarization direction, and the second smart antenna device  2  can produce a vertical polarization direction. In addition, the radiation pattern of the smart antenna assembly A can also be adjusted to be one directing to the first direction (for example, the negative direction of the X axis), the second direction (for example, the positive direction of the X axis), the third direction (for example, the positive direction of the Y axis), or the fourth direction (for example, the negative direction of the Y axis) according to needs. 
     Further, referring again to  FIG. 15A  and  FIG. 16A , when the first smart antenna device  1  selects the first polarization antenna  11  (for example, a horizontal polarization antenna), and the second smart antenna device  2  selects the third antenna  21  (for example, a horizontal polarization antenna), radiation patterns having similar pattern shape and directing to four different directions (the first, second, third and fourth directions) can be produced according to the outputting of direct current signals from the first to fourth control terminals P 1  to P 4 . Thereby, when a user&#39;s device transmits and receives signals in the first to fourth directions, the user can have the same user experience. In addition, referring to  FIG. 15B  and  FIG. 16B , when the first smart antenna device  1  selects the second polarization antenna  12  (for example, a vertical polarization antenna), and the second smart antenna device  2  selects the fourth polarization antenna  22  (for example, a vertical polarization antenna), radiation patterns having similar pattern shape and directing to four different directions (the first, second, third and fourth directions) can be produced according to the outputting of direct current signals from the first to fourth control terminals P 1  to P 4 . In other words, the smart antenna assembly A provided by the present disclosure can not only generate four different radiation patterns in the same polarization direction, but also generate different radiation patterns in different polarization directions. 
     One of the beneficial effects of the present disclosure is that, through the technical features of “the first control terminal P 1  is used to turn on the first switch element  131  and the third switch element  133 , and the second control terminal P 2  is used to turn on the second switch element  132  and the fourth switch element  134 ,” the smart antenna assembly A can change its radiation pattern. That is, the first control terminal P 1  and the second control terminal P 2  can be used to adjust two different radiation patterns of the smart antenna assembly A. Therefore, the smart antenna assembly A provided by the present disclosure is an antenna structure having at least one omnidirectional radiation and two directional radiations. 
     Further, through the technical feature of “the switching circuit  4  selects one of the first polarization antenna  11  and the second polarization antenna  12  based on a control signal, so as to transmit a first radio frequency signal to the first polarization antenna  11 , or to transmit a second radio frequency signal to the second polarization antenna  12 ,” the smart antenna assembly A provided by the present disclosure can switch its polarization direction. That is, it can select a horizontal polarization antenna or a vertical polarization antenna based on practical requirement, and thereby has Multi-input Multi-output (MIMO) properties. 
     Furthermore, by adopting a second smart antenna device  2 , the smart antenna assembly A provided by the present disclosure can produce four radiation patterns having different directions. Also, by adopting a switching circuit  4 , a polarization direction of the smart antenna assembly A can be switched. That is, in certain embodiments, a polarization direction of the smart antenna assembly A can be selected first, and then the direction of the radiation pattern of the smart antenna assembly A is selected based on needs, so as to cover all the radiation directions. 
     Moreover, since the first polarization antenna  11  is disposed on the first substrate  11 S, and the second polarization antenna  12  is disposed on the second substrate  12 S, the smart antenna assembly A provided by the present disclosure can be disposed at any position deemed necessary according to practical requirements. In other words, by arranging the first switch element  131 , second switch element  132 , third switch element  133 , fourth switch element  134 , first control terminal P 1  and second control terminal P 2  on the first substrate  11 S and the second substrate  12 S, and using the feeding lines of the first coaxial cable  1113 ′ and the second coaxial cable  1213 ′, the smart antenna assembly A can be easily disposed at any position deemed necessary or possible according to practical requirements, thereby increasing product design flexibility and use flexibility. 
     The foregoing description of the exemplary embodiments of the present disclosure has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the present disclosure to the precise forms disclosed. Many modifications and variations are possible in light of the above teaching. 
     The embodiments were selected and described in order to explain the principles of the present disclosure and their practical application so as to enable others skilled in the art to utilize the present disclosure and various embodiments and with various modifications as are suited to the particular use contemplated. Alternative embodiments will become apparent to those skilled in the art to which the present disclosure pertains without departing from its spirit and scope.