Patent Publication Number: US-9843111-B2

Title: Antennas including an array of dual radiating elements and power dividers for wireless electronic devices

Description:
TECHNICAL FIELD 
     The present inventive concepts generally relate to the field of wireless communications and, more specifically, to antennas for wireless communication devices. 
     BACKGROUND 
     Wireless communication devices such as cell phones and other user equipment may include antennas that may be used to communicate with external devices. These antennas may produce broad radiation patterns. Some antenna designs, however, may facilitate irregular radiation patterns whose main beam is directional. 
     SUMMARY 
     Various embodiments of the present inventive concepts include a wireless electronic device including a plurality of dual radiating elements, each of which includes a first radiating element and a second radiating element. The wireless electronic device may include a plurality of power dividers, a respective one of which is associated with a respective one of the plurality of dual radiating antennas, and may be configured to divide a power of a signal into a first portion of the power and a second portion of the power, and may be configured to apply the signal at the first portion of the power to the respective first radiating element and to apply the signal at the second portion of the power to the respective second radiating element. The wireless electronic device may be configured to resonate at a resonant frequency corresponding to a respective first radiating element and/or a respective second radiating element of at least one of the plurality of dual radiating antennas when excited by the signal transmitted by at least one of the plurality of dual radiating antennas. 
     According to various embodiments, a respective one of the plurality of dual radiating antennas may be configured such that a first polarization of the signal at the first portion of the power applied to the first radiating element is orthogonal to a second polarization of the signal at the second portion of the power applied to the second radiating element. According to various embodiments, a third polarization of a respective first radiating element of a first one of the plurality of dual radiating antennas may be orthogonal to a fourth polarization of a respective first radiating element of a second one of the plurality of dual radiating antennas that is adjacent the first one of the plurality of dual radiating antennas. According to various embodiments, a fifth polarization of a respective second radiating element of the first one of the plurality of dual radiating antennas may be orthogonal to a sixth polarization of a respective second radiating element of the second one of the plurality of dual radiating antennas that is adjacent the first one of the plurality of dual radiating antennas. According to various embodiments, the third polarization may be orthogonal to the fifth polarization, and/or the fourth polarization may be orthogonal to the sixth polarization. 
     According to various embodiments, the wireless electronic device may include a first subarray comprising a first plurality of the dual radiating antennas and a first plurality of power dividers, a respective one of which is associated with a respective one of the first plurality of the dual radiating antennas. The wireless electronic device may include a second subarray including a second plurality, exclusive of the first plurality, of the dual radiating antennas and a second plurality of power dividers, a respective one of which is associated with a respective one of the second plurality of the dual radiating antennas. In some embodiments, the first subarray and/or the second subarray may be configured to transmit multiple-input and multiple-output (MIMO) communication and/or diversity communication. 
     According to various embodiments, the plurality of dual radiating antennas may be further configured such that a seventh polarization of signals at each of the first radiating elements of the first plurality of the dual radiating antennas of the first subarray may be orthogonal to an eighth polarization of signals at each of the first radiating elements of the second plurality of the dual radiating antennas of the second subarray. The plurality of dual radiating antennas may be configured such that a ninth polarization of signals at each of the second radiating elements of the first plurality of the dual radiating antennas of the first subarray may be orthogonal to a ninth polarization of signals at each of the second radiating elements of the second plurality of the dual radiating antennas of the second subarray. 
     According to various embodiments, the first plurality of power dividers of the first subarray may be each configured to provide the signal at the first portion of the power of the signal that is greater than zero. The second plurality of power dividers of the second subarray may be each configured to provide the signal at the second portion of the power of the signal that is greater than zero. 
     According to various embodiments, the first plurality of power dividers of the first subarray may be each configured to provide the signal at the first portion of the power of the signal that is greater than zero, and/or the second plurality of power dividers of the second subarray may be each configured to provide the signal at the second portion of the power of the signal that is greater than zero, in response to a signal strength of the signal being less than a first threshold. In some embodiments, the first plurality of power dividers of the first subarray may be each configured to provide all of the power of the signal to the first radiating element and the second plurality of power dividers of the second subarray may be each configured to provide all of the power of the signal to the second radiating element, or the first plurality of power dividers of the first subarray may be each configured to provide all of the power of the signal to the second radiating element and the second plurality of power dividers of the second subarray may be each configured to provide all of the power of the signal to the first radiating element. 
     According to various embodiments, the first plurality of power dividers of the first subarray may be each configured to provide all of the power of the signal to the first radiating element and the second plurality of power dividers of the second subarray may be each configured to provide all of the power of the signal to the second radiating element, or the first plurality of power dividers of the first subarray may be each configured to provide all of the power of the signal to the second radiating element and the second plurality of power dividers of the second subarray may be each configured to provide all of the power of the signal to the first radiating element, in response to a signal strength of the signal being greater than a first threshold and less than a second threshold. 
     According to various embodiments, a selected one of the first plurality of power dividers of the first subarray or the second plurality of power dividers of the second subarray may be configured to provide all of the power of the signal to a respective first radiating element and zero power to a respective second radiating element of a respective dual radiating antenna or may be configured to provide all of the power of the signal to a respective second radiating element and zero power to a respective first radiating element of a respective dual radiating antenna. The remaining ones of the first plurality of power dividers of the first subarray and the second plurality of power dividers of the second subarray, exclusive of the selected one, may be configured to provide zero power to respective first radiating elements and respective second radiating elements of respective dual radiating antennas. 
     According to various embodiments, the selected one of the first plurality of power dividers of the first subarray or the second plurality of power dividers of the second subarray may be configured to provide all of the power of the signal to the respective first radiating element and zero power to the respective second radiating element of the respective dual radiating antenna or may be configured to provide all of the power of the signal to the respective second radiating element and zero power to the respective first radiating element of the respective dual radiating antenna, in response to a signal strength of the signal being greater than a second threshold. 
     According to various embodiments, the wireless electronic device may include a control signal that is applied to the respective one of the plurality of power dividers and that provides an indication of a value of the first portion of the power and/or the second portion of the power. In some embodiments, the wireless electronic device may include a controller that is configured to generate the control signal. 
     According to various embodiments, the first radiating element may include a first dielectric block, and/or the second radiating element may include a second dielectric block. According to various embodiments, the first radiating element may include a first patch element, and/or the second radiating element may include a second patch element. 
     According to various embodiments, the wireless electronic device may include a plurality of first striplines and a plurality of second striplines. A respective one of the plurality of the first striplines and a respective one of the plurality of the second striplines may be electrically coupled to a respective one of the plurality of power dividers. A respective one of the plurality of the first striplines may be associated with the first radiating element of the respective one of the plurality of dual radiating antennas, and/or a respective one of the plurality of the second striplines may associated with the second radiating element of the respective one of the plurality of dual radiating antennas. 
     According to various embodiments, the wireless electronic device may include a first conductive layer including a plurality of first slots, and/or a second conductive layer including the plurality of first striplines. A respective one of the plurality of first slots may be associated with a respective one of the plurality of first striplines. The wireless electronic device may include a third conductive layer with the plurality of second striplines and/or a fourth conductive layer with a plurality of second slots. A respective one of the plurality of second slots may be associated with a respective one of the plurality of second striplines. The first, second, third, and fourth conductive layers may be arranged in a face-to-face relationship, separated from one another by first, second, and third dielectric layers, respectively. 
     According to various embodiments a wireless electronic device may include first, second, third, and fourth conductive layers arranged in a face-to-face relationship, separated from one another by first, second, and third dielectric layers, respectively. The wireless electronic device may include a plurality of first radiating elements and/or a plurality of second radiating elements. The first conductive layer may include a plurality of first slots, the second conductive layer may include a plurality of first striplines, the third conductive layer may include a plurality of second striplines, and/or the fourth conductive layer may include a plurality of second slots. In some embodiments, respective ones of the plurality of second radiating elements may be associated with and at least partially overlap respective ones of the plurality of first radiating elements. In some embodiments, a respective one of the plurality of first radiating elements may be associated with and at least partially overlap a respective one of the plurality of the first slots, and/or a respective one of the plurality of second radiating elements may be associated with and at least partially overlaps a respective one of the plurality of the second slots. In some embodiments, the wireless electronic device may be configured to resonate at a resonant frequency corresponding to at least one of the plurality of the first radiating elements and/or at least one of the plurality of second radiating elements when excited by a signal transmitted and/or received though the first stripline and/or second stripline. According to various embodiments, a first one of the plurality of the first radiating elements and a respective first one of the plurality of the second radiating elements may be configured such that a first polarization of the signal at the first one of the plurality of the first radiating elements is orthogonal to a second polarization of the signal at the respective first one of the plurality of the second radiating elements. 
     According to various embodiments, a second one of the plurality of the first radiating elements and a respective second one of the plurality of the second radiating elements may be configured such that a third polarization of the signal at the second one of the plurality of the first radiating elements is orthogonal to a fourth polarization of the signal at the respective second one of the plurality of the second radiating elements. The first one of the plurality of the first radiating elements and the respective second one of the plurality of the first radiating elements may be adjacent to one another, and/or the first one of the plurality of the second radiating elements and the respective second one of the plurality of the second radiating elements may be adjacent to one another. In some embodiments, the third polarization may be orthogonal to the first polarization. 
     According to various embodiments, the wireless electronic device may include a plurality of power dividers. A respective one of the plurality of the power dividers may be electrically coupled to a respective one of the plurality of the first striplines and a respective one of the plurality of the second striplines. A respective one of the plurality of the first striplines may be configured to receive the signal at the first portion of a power of the signal from a respective one of the power dividers and/or a respective one of the plurality of the second striplines may be configured to receive the signal at a second portion of the power of the signal from the respective one of the power dividers. The wireless electronic device may include a fifth conductive layer including the plurality of first radiating elements, and/or a sixth conductive layer including the plurality of second radiating elements. The plurality of first radiating elements may include a plurality of first patch elements, and/or the plurality of second radiating elements may include a plurality of second patch elements. 
     According to various embodiments, the wireless electronic device may include a controller that is configured to generate a control signal that is applied to the respective one of the plurality of the power dividers and that provides an indication of a value of the first portion of the power and/or a second portion of the power. According to various embodiments, the plurality of first radiating elements may include a plurality of first dielectric blocks on the first conductive layer. A respective one of the plurality of the first dielectric blocks may at least partially overlap a respective one of the plurality of first slots. The plurality of second radiating elements may include a plurality of second dielectric blocks on the fourth conductive layer, and/or a respective one of the plurality of the second dielectric blocks may at least partially overlap a respective one of the plurality of second slots. 
     Other devices and/or operations according to embodiments of the inventive concepts will be or become apparent to one with skill in the art upon review of the following drawings and detailed description. It is intended that all such additional devices and/or operations be included within this description, be within the scope of the present inventive concepts, and be protected by the accompanying claims. Moreover, it is intended that all embodiments disclosed herein can be implemented separately or combined in any way and/or combination. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this application, illustrate certain embodiment(s). In the drawings: 
         FIG. 1A  illustrates a single patch antenna on a printed circuit board (PCB), according to various embodiments of the present inventive concepts. 
         FIG. 1B  illustrates a plan view of the single patch antenna of  FIG. 1A , according to various embodiments of the present inventive concepts. 
         FIG. 1C  illustrates radiation patterns at two different phases for the single patch antenna of  FIGS. 1A and 1B , according to various embodiments of the present inventive concepts. 
         FIG. 2  illustrates the single patch antenna of  FIGS. 1A and 1B  in a wireless electronic device, according to various embodiments of the present inventive concepts. 
         FIG. 3A  illustrates the radiation pattern around a wireless electronic device such as a smartphone, including the single patch antenna of  FIG. 2 , according to various embodiments of the present inventive concepts. 
         FIG. 3B  illustrates the absolute far field gain, at 15.1 GHz excitation, along a wireless electronic device including the single patch antenna of  FIG. 2 , according to various embodiments of the present inventive concepts. 
         FIG. 4A  illustrates a single dielectric resonator antenna (DRA) on a printed circuit board (PCB), according to various embodiments of the present inventive concepts. 
         FIG. 4B  illustrates a plan view of the single DRA on a printed circuit board (PCB) of  FIG. 4A , according to various embodiments of the present inventive concepts. 
         FIG. 4C  illustrates the radiation pattern at two different phases of the single DRA of  FIGS. 4A and 4B , according to various embodiments of the present inventive concepts. 
         FIG. 5A  illustrates a dual radiating element antenna including two radiating elements with the same polarization, according to various embodiments of the present inventive concepts. 
         FIG. 5B  illustrates a dual radiating element antenna including two radiating elements with orthogonal polarization, according to various embodiments of the present inventive concepts. 
         FIGS. 6A and 6B  illustrate dual patch antennas, according to various embodiments of the present inventive concepts. 
         FIG. 7A  illustrates the front side of a wireless electronic device such as a smartphone, including the dual patch antenna of  FIG. 5B ,  FIG. 6A , and/or  FIG. 6B  according to various embodiments of the present inventive concepts. 
         FIG. 7B  illustrates the radiation pattern associated with a patch antenna element on the front side of a wireless electronic device such as a smartphone of  FIG. 7A , according to various embodiments of the present inventive concepts. 
         FIG. 8A  illustrates the back side of a wireless electronic device such as a smartphone, including the dual patch antenna of  FIG. 5B ,  FIG. 6A , and/or  FIG. 6B  according to various embodiments of the present inventive concepts. 
         FIG. 8B  illustrates the radiation pattern associated with a patch antenna element on the back side of a wireless electronic device such as a smartphone of  FIG. 8A , according to various embodiments of the present inventive concepts. 
         FIG. 9  illustrates the absolute far field gain, at 15.1 GHz excitation, along a wireless electronic device including the dual patch antenna of  FIG. 6A  and/or  FIG. 6B , according to various embodiments of the present inventive concepts. 
         FIGS. 10A and 10B  illustrate the absolute far field gain using different signal feeding schemes, at 15.1 GHz excitation, along a wireless electronic device including the dual patch antenna of  FIG. 6A  and/or  FIG. 6B , according to various embodiments of the present inventive concepts. 
         FIGS. 11A and 11B  illustrate dual DRA antennas, according to various embodiments of the present inventive concepts. 
         FIG. 12A  illustrates the front side of a wireless electronic device such as a smartphone, including an array of dual patch antenna elements of  FIG. 6A  and/or  FIG. 6B , according to various embodiments of the present inventive concepts. 
         FIG. 12B  illustrates the back side of a wireless electronic device such as a smartphone, including an array of dual patch antenna elements of  FIG. 6A  and/or  FIG. 6B , according to various embodiments of the present inventive concepts. 
         FIGS. 13A-13C  illustrate the radiation pattern around the wireless electronic device, including a dual patch array antenna of  FIGS. 12A and 12B , according to various embodiments of the present inventive concepts. 
         FIG. 14  illustrates a wireless electronic device with a metal ring antenna, according to various embodiments of the present inventive concepts. 
         FIG. 15  illustrates a wireless electronic device with a metal ring antenna as well as dual radiating element array antenna, according to various embodiments of the present inventive concepts. 
         FIG. 16  illustrates a wireless electronic device with a metal ring antenna as well as dual radiating element Multiple Input and Multiple Output (MIMO) array antenna, according to various embodiments of the present inventive concepts. 
         FIGS. 17A and 17B  illustrate the radiation patterns around the wireless electronic device for various subarrays of the dual patch MIMO array antenna including the antenna of  FIG. 16 , according to various embodiments of the present inventive concepts. 
         FIG. 18  illustrates a wireless electronic device such as a cell phone including one or more antennas according to any of  FIGS. 1 to 17B and 19 to 34 , according to various embodiments of the present inventive concepts. 
         FIG. 19  illustrates a wireless electronic device including an array of dual radiating element antennas, according to various embodiments of the present inventive concepts. 
         FIG. 20  illustrates a plurality of dual radiating element antennas according to  FIG. 19  and power dividers, according to various embodiments of the present inventive concepts. 
         FIG. 21  illustrates dual radiating element antennas according to  FIG. 19  and power dividers along with a controller for diversity combining systems, according to various embodiments of the present inventive concepts. 
         FIG. 22  illustrates a plurality of dual radiating element antennas according to  FIG. 19  and power dividers for MIMO systems, according to various embodiments of the present inventive concepts. 
         FIG. 23  illustrates a power divider, according to various embodiments of the present inventive concepts. 
         FIGS. 24A-24C  illustrate the absolute far field gain at different points along the power divider of  FIG. 23 , according to various embodiments of the present inventive concepts. 
         FIG. 25  illustrates a switch for selecting different feeding schemes, according to various embodiments of the present inventive concepts. 
         FIGS. 26A-26C  illustrate the absolute far field gain for different feeding schemes using the switch of  FIG. 25 , according to various embodiments of the present inventive concepts. 
         FIG. 27  illustrates antenna coverage provided by a dual radiating element antenna array of  FIGS. 19 to 22 , according to various embodiments of the present inventive concepts. 
         FIG. 28  illustrates signals received by dual radiating element antenna with subarrays, according to various embodiments of the present inventive concepts. 
         FIG. 29A  illustrates a dual patch MIMO antenna array of  FIG. 22 , according to various embodiments of the present inventive concepts. 
         FIGS. 29B to 29E  illustrate the radiation pattern around the wireless electronic device, including a dual patch MIMO antenna array of  FIG. 29A , according to various embodiments of the present inventive concepts. 
         FIG. 30A  illustrates a dual patch MIMO antenna array including power dividers, according to various embodiments of the present inventive concepts. 
         FIGS. 30B and 30C  illustrate the radiation pattern around the wireless electronic device including a dual patch MIMO antenna array including the power divider of  FIG. 30A , according to various embodiments of the present inventive concepts. 
         FIGS. 31A and 31B  illustrate a dual patch MIMO antenna subarrays, according to various embodiments of the present inventive concepts. 
         FIG. 32  illustrates operations that may be performed by a controller for the dual patch MIMO antenna subarrays of  FIGS. 20-22, 31A and/or 31B , according to various embodiments of the present inventive concepts. 
         FIG. 33  illustrates a flowchart for determining modes of operating any of the antennas of  FIGS. 19-22, 29A, 30A, 31A , and/or  31 B, according to various embodiments of the present inventive concepts. 
         FIG. 34  illustrates a dual patch antenna array of any of  FIGS. 19-22, 29A, 30A, 31A , and/or  31 B, according to various embodiments of the present inventive concepts. 
     
    
    
     DETAILED DESCRIPTION 
     The present inventive concepts now will be described more fully with reference to the accompanying drawings, in which embodiments of the inventive concepts are shown. However, the present application should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and to fully convey the scope of the embodiments to those skilled in the art. Like reference numbers refer to like elements throughout. 
     The contents of U.S. patent application Ser. No. 14/681,432 filed on Apr. 8, 2015 are replicated herewith in the Specification of the present application under the heading “Antenna Including Dual Radiating Elements” and as well as corresponding to  FIGS. 1A to 18  of the present application. Additional embodiments are described in the section under the heading “Antenna Including an Array of Dual Radiating Elements and Power Dividers” and may be combined with any of the previous embodiments. Additionally,  FIGS. 19 to 34  have been added herewith and may be combined with any of previous  FIGS. 1A to 18 . 
     Antenna Including Dual Radiating Elements 
     A patch antenna is commonly used in microwave antenna design for wireless electronic devices such as mobile terminals. A patch antenna may include a radiating element on a printed circuit board (PCB). As used herein, a PCB may include any conventional printed circuit board material that is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces. The PCB may comprise laminate, copper-clad laminates, resin-impregnated B-stage cloth, copper foil, metal clad printed circuit boards and/or other conventional printed circuit boards. In some embodiments, the printed circuit board is used for surface mounting of electronic components thereon. The PCB may include one or more integrated circuit chip power supplies, integrated circuit chip controllers and/or other discrete and/or integrated circuit passive and/or active microelectronic components, such as surface mount components thereon. The PCB may comprise a multilayered printed wiring board, flexible circuit board, etc., with pads and/or metal traces that are on the surface of the board and/or on intervening layers of the PCB. 
     Patch antenna designs may be compact in size and easy to manufacture since they may be implemented as printed features on PCBs. A dielectric resonator antenna (DRA) is also commonly used in microwave antenna design for wireless electronic devices such as mobile terminals. The DRA may include a radiating element such as a flux couple on a PCB with a dielectric block on the flux couple. 
     Various wireless communication applications may use patch antennas and/or DRAs. Patch antennas and/or DRAs may be suitable for use in the millimeter band radio frequencies in the electromagnetic spectrum from 10 GHz to 300 GHz. Patch antennas and/or DRAs may each provide radiation beams that are quite broad. A potential disadvantage of patch antenna designs and/or DRA designs may be that the radiation pattern is directional. For example, if a patch antenna is used in a mobile device, the radiation pattern may only cover half the three dimensional space around the mobile device. In this case, the antenna produces a radiation pattern that is directional, and may require the mobile device to be directed towards the base station for adequate operation. 
     Various embodiments described herein may arise from the recognition that the patch antenna and/or the DRA may be improved by adding another radiating element on or near the opposite side of the printed circuit board, producing a dual patch antenna and/or a dual DRA design. The dual radiating elements may improve the antenna performance by producing a radiation pattern that covers the three-dimensional space around the mobile device. 
     Referring now to  FIG. 1A , the diagram illustrates a single patch antenna  110  on a printed circuit board (PCB)  109 . The PCB  109  includes a first conductive layer  101 , a second conductive layer  102 , and a third conductive layer  103 . The first, second, and/or third conductive layers ( 101 ,  102 ,  103 ) may be arranged in a face-to-face relationship. The first, second, and third conductive layers ( 101 ,  102 ,  103 ) are separated from one another by a first dielectric layer  107  and/or a second dielectric layer  108 , respectively. A first radiating element  104  may be in the first conductive layer  101 . A stripline  106  may be in the third conductive layer of the single patch antenna  110 . A ground plane  105  may be in the second conductive layer  102 . The ground plane  105  may include an opening or slot  112 . The width of the slot  112  may be W ap . A signal may be received and/or transmitted through the stripline  106 , causing the single patch antenna  110  to resonate. 
     Referring now to  FIG. 1B , a plan view of the single patch antenna  110  of  FIG. 1A  is illustrated. The first radiating element  104  may have a length L and width W. The first radiating element  104  may overlap the stripline  106 . The stripline may overlap a slot  112  in the ground plane of the single patch antenna  110 . The slot  112  in the ground plane of the single patch antenna  110  may have width W ap  and/or length L ap . In some embodiments, the stripline  106  may extend beyond the first radiating element  104 , for a length L s  from the slot  112 . 
     Electromagnetic properties of the described antenna structures may be determined by physical dimensions and/or other parameters. For example, parameters such as stripline width, stripline positioning, dielectric layer thickness, dielectric layer permittivity, dimensions W ap  and/or length L ap  of the slot in the ground plane, and/or dimensions L and/or W of the first radiating element  104  may affect the electromagnetic properties of antenna structures and subsequently the antenna performance. In some embodiments, the relative permittivity of the first dielectric layer  107  may be ∈τ 1  while the relative permittivity of the second dielectric layer may be ∈τ 2 . ∈τ 2  may be different from ∈τ 1 . 
     Referring now to  FIG. 1C , radiation patterns for two different phases of the single patch antenna  110  of  FIGS. 1A and 1B  are illustrated. The radiation patterns at phase φ=0° and phase φ=90° are illustrated. Both radiation patterns appear to be broad and symmetric. However, the radiation patterns are directional, mostly covering one half the space around the antenna. In other words, if the single patch antenna  110  is placed in a mobile device, one side of the mobile device would have excellent performance while the opposite side of the mobile device would have poor performance. This directional behavior of the single patch antenna may provide good performance in certain orientations with respect to a base station and/or poor performance in other orientations with respect to the base station. 
     Referring now to  FIG. 2 , a wireless electronic device  201  that includes the single patch antenna  110  of  FIGS. 1A and 1B  is illustrated. The single patch antenna  110  is positioned along an edge of the wireless electronic device  201 . Other components may be included in the wireless electronic device  201 , but are not illustrated for purposes of simplicity. The polarization of the single patch antenna  110  may be in the direction indicated by arrow  202  in  FIG. 2 , such as, for example, towards the top of the wireless electronic device  201 . 
     Referring now to  FIG. 3A , the radiation pattern around a wireless electronic device  201  including the single patch antenna  110  of  FIGS. 1A and 1B  is illustrated. When the single patch antenna  110  is excited at 15.1 GHz, an irregular radiation pattern is formed around the wireless electronic device  201 . The radiation pattern around the wireless electronic device  201  exhibits directional distortion with broad, even radiation covering one half the space around the antenna but poor radiation around the other half of the antenna. Hence, this antenna may not be suitable for communication at this frequency since some orientations exhibit poor performance. 
     Referring now to  FIG. 3B , the absolute far field gain, at 15.1 GHz excitation, along a wireless electronic device  201  including the single patch antenna  110  of  FIG. 2  is illustrated. The axis Theta represents the y-z plane while the axis Phi represents the x-y plane around the wireless electronic device  201  of  FIG. 2 . Similar to the resulting radiation pattern of  FIG. 3A , the absolute far field gain exhibits satisfactory gain characteristics in one direction around the wireless electronic device  201 , such as, for example, spanning broadly in the x-y plane. However, in the y-z plane, good absolute far field gain results are obtained in one direction, for example, 90° to 180° around the wireless electronic device  201 , but poor absolute far field gain results are obtained in the opposite direction in the y-z plane, for example, 0° to 90° around the wireless electronic device  201 . 
     Referring now to  FIG. 4A , the diagram illustrates a single dielectric resonator antenna (DRA)  410  on a printed circuit board (PCB)  409 . The PCB  409  includes a first conductive layer  401  and/or a second conductive layer  402 . The first and second conductive layers ( 401 ,  402 ) may be arranged in a face-to-face relationship. The first and second conductive layers ( 401 ,  402 ) may be separated from one another by a dielectric layer  403 . The dielectric layer  403  may be a single layer or a multilayer insulating material or a material that is a very poor conductor of electric current. The dielectric layer  403  may be formed of oxide, nitride, and/or insulating metal oxides such as hafnium oxide, aluminum oxide, and/or the like. The dielectric layer  403  may have a thickness H d . A radiating element  405  may be in the first conductive layer  401 . The radiating element  405  may comprise a flux couple. The radiating element  405  may include an opening or slot  412 . A dielectric block  406  may be on the radiating element  405 , remote from the dielectric layer  403 . The dielectric block  406  may have a length L and height H. A stripline  404  may be in the second conductive layer  402  of the DRA  410 . The width of the slot  412  may be W ap . A signal may be received and/or transmitted through the stripline  404 , causing the DRA  410  to resonate. 
     Referring now to  FIG. 4B , a plan view of the DRA  410  of  FIG. 4A  is illustrated. The dielectric block  406  may have a length L and width W. In some embodiments, the length L and width W may be equal. The dielectric block  406  may overlap the stripline  404 . The stripline  404  may overlap a slot  412  in the radiating element  405  of the DRA  410 . The slot  412  in the radiating element  405  of the DRA  410  may have a width W ap  and/or a length L ap . In some embodiments, the stripline  404  may extend beyond the dielectric block  406  for a length L s  from the slot  412 . 
     Electromagnetic properties of the described DRA antenna structure may be determined by physical dimensions and other parameters. For example, parameters such as stripline  404  width, stripline  404  positioning, dielectric layer  403  thickness H d , dielectric layer permittivity ∈τ, dimensions W ap  and/or a length L ap  of the slot  412  in the radiating element  405 , and/or dimensions L and/or W of the dielectric block  406  may affect the electromagnetic properties of DRA antenna structures and subsequently the antenna performance. 
     Referring now to  FIG. 4C , radiation patterns for two different phases of the DRA  410  of  FIGS. 4A and 4B  are illustrated. The radiation patterns at phase φ=0° and phase φ=90° are illustrated. Both radiation patterns appear to be broad and symmetric. However, the radiation patterns are directional, mostly covering one half the space around the antenna. In other words, if the DRA  410  is placed in a mobile device, one side of the mobile device would have excellent performance while the opposite side of the mobile device would have poor performance. This directional behavior of the DRA antenna may provide good performance in certain orientations with respect to a base station and/or poor performance in other orientations with respect to the base station. 
       FIGS. 5A and 5B , may include the single patch antenna of  FIGS. 1A and 1B , and/or the single DRA of  FIGS. 4A and 4B . Referring now to  FIG. 5A , a dual radiating element antenna  500  including two radiating elements with the same polarization is illustrated. The dual radiating element antenna  500  may be on a PCB  507  and include a first radiating element  501  and a second radiating element  502 . An electronics circuit package  503  may be included in the PCB  507 , between the first radiating element  501  and the second radiating element  502 . In some embodiments, the first radiating element  501  may include the first radiating element  104  of  FIG. 1A . In some embodiments, the first radiating element  501  may include the radiating element  405  of  FIG. 4A . The electronics circuit package  503  may include circuits for transmitting and/or receiving signals, circuits for adjusting the polarization of signals, impedance matching circuits, and/or a power divider  506  for signal splitting and/or switching. The power divider  506  may be electrically coupled and/or connected to components in the electronics circuit package  503  and/or to a stripline associated with the dual radiating element antenna  500 . Arrows  504  and  505  illustrate the respective polarizations of signals at the first radiating element  501  and the second radiating element  502 . In this case, a signal at the first radiating element  501  has a same polarization  504  as the polarization  505  of a signal at the second radiating element  502 . Since the first and second radiating elements  501  and  502  have the same polarization, high mutual coupling between the antenna elements may result. This high mutual coupling may result in disturbance of the signals at each of the first radiating element  501  and the second radiating element  502 , causing radiation pattern distortion. In some embodiments, the signal at the first radiating element  501  may cancel and/or interfere with the signal at the second radiating element  502 . In other words, in this configuration signals with the same polarization at the first and second radiating elements  501  and  502 , the antenna elements may not work properly together. Changing polarization of the signals may improve performance of this antenna, as will be discussed with respect to  FIG. 5B . 
     Referring now to  FIG. 5B , a dual radiating antenna  500  including two radiating elements with orthogonal polarization is illustrated. The electronics circuit package  503  may include circuits for configuring the polarization of signals at the first and second radiating elements  501  and  502 . The polarization of a signal may be associated with a physical orientation of the signal. Arrows  504  and  505  illustrate the respective polarizations of signals at the first radiating element  501  and the second radiating element  502 . In this case, a signal at the first radiating element  501  has polarization  504  that is orthogonal to the polarization  505  of the signal at the second radiating element  502 . Since the signal at the first radiating element  501  is orthogonal to the signal at the second radiating element  502 , the antenna elements may work together to form an omni-directional radiation pattern. The radiation pattern for the upper half of the antenna at the first radiating element  501  may be orthogonal to the radiation pattern for the lower half of the antenna at the second radiating element  502 , providing high isolation such as, for example −35 dB.  FIG. 5B  illustrates the polarization of the signals as a non-limiting example. In some embodiments, the polarization of the signal may be based on linear polarization, circular polarizations, Right Hand Circular Polarization (RHCP) or Left Hand Circular Polarization (LHCP), and/or elliptical polarization. 
     Still referring to  FIGS. 5A and 5B , in various embodiments described herein, performance of the dual radiating antenna  500  with orthogonal signal polarization may be improved by including a power divider  506  circuit in the electronics package  503 . As discussed earlier, a signal may be received and/or transmitted through the stripline associated with an antenna. A power divider  506  may be electrically connected and/or coupled to the stripline. A power divider  506  may operate to split the signal that is received and/or transmitted through the stripline. For example, a power divider  506  may be configured to control a power of the signal received at the stripline that is applied to the first radiating element  501  and/or the second radiating element  502 . In other words, a first portion of the power of the signal may be applied to the first radiating element  501  for a first period of time and/or a second portion of the power of the signal may be applied to the second radiating element  502  for a second period of time. In some embodiments, the first period of time may overlap and/or be congruent in time with the second period of time. In some embodiments, the first time period may not overlap the second time period. In some embodiments, the power divider  506  may be configured to provide a first portion of the power of the signal to the first radiating element  501  that is orthogonal to the second portion of the power of the signal to the second radiating element  502 . In some embodiments, the power divider  506  may be configured to provide all of the power of the signal at the stripline to the first radiating element  501  for a first period of time and to provide all of the power of the signal at the stripline to the second radiating element  502  for a second period of time. The first and second time periods may not overlap with one another when the power divider  506  switches between providing all of the power of the signal at the stripline to the first radiating element  501  or the second radiating element  502 . Switching between applying power to the first radiating element  501  and the second radiating element  502  may occur periodically in time and/or according to a predefined time-based function. 
     In some embodiments, any of the power splitting operations may be constant over time or may vary over time. The mode of operation of the power divider  506  may switch between a first mode of providing different portions of the signal power to each of the first and second radiating elements  501  and  502  to a second mode of providing all of the power of the signal at the stripline to the first and second radiating elements  501  and  502  for different periods of time. The mode of operation of the power divider  506  may be controlled based on communication channel conditions, user selection, and/or a predetermined pattern of operation. 
     In some embodiments, the first and second radiating elements  501  and/or  502  of  FIGS. 5A and 5B  may comprise first and/or second patch elements. Now referring to  FIG. 6A , a dual patch antenna  600  is illustrated. The dual patch antenna  600  may include a first conductive layer  612  and a second conductive layer  614 . The first and second conductive layers ( 612 ,  614 ) may be arranged in a face-to-face relationship. The first and second conductive layers ( 612 ,  614 ) may be separated from one another by a first dielectric layer  604 . A first patch element  605  may be in a fourth conductive layer  611 . A second patch element  606  may be in a fifth conductive layer  613 . A stripline  602  may be in the second conductive layer  612  of the dual patch antenna  600 . A ground plane  601  may be in the first conductive layer  612 . The ground plane may include an opening or slot  607 . The width of the slot  607  may be W ap . The width of the slot  607  may control impedance matching of the dual patch antenna  600  to the wireless electronic device  201 . In some embodiments, a conductive layer  615  may be between dielectric layers  617  and  618 . Conductive layer  615  may include a PCB ground plane  616  associated with a PCB. In some embodiments, the PCB ground plane  616  may include a slot  626  of width W ap . In some embodiments, the slot  607  may overlap with the first patch element  605  and/or the second patch element  606 . In some embodiments, the slot  607  may overlap with the stripline  602 . In some embodiments, the slot  607  may laterally overlap with the first patch element  605  and/or the second patch element  606 . In some embodiments, the slot  607  may laterally overlap with the stripline  602 . A signal may be received and/or transmitted through the stripline  602 , causing the dual patch antenna  600  to resonate. In some embodiments, the second patch element  606  may have a different corresponding stripline. The two striplines may each correspond to a different patch element and thus may be used by the power divider  506  of  FIG. 5  to separately provide signals to the first patch element  605  and/or the second patch element  606 . 
     Still referring to  FIG. 6A , a power divider may be associated with the dual patch antenna  600 . The power divider is not illustrated in  FIG. 6A  for simplicity. The power divider may be internal or external to the dual patch antenna  600  but is electrically connected and/or coupled to the stripline  602 . The power divider may be configured to control a power of the signal that is applied to the first patch element  605  and/or the second patch element  606 . The first patch element  605  and/or the second patch element  606  may be configured such that a first polarization of the signal at the first patch element  605  is orthogonal to a second polarization of the signal at the second patch element  606 . 
     In some embodiments, the first and second radiating elements  501  and/or  502  of  FIGS. 5A and 5B  may comprise first and/or second patch elements. Now referring to  FIG. 6B , a dual patch antenna  600  is illustrated. The dual patch antenna  600  may include a first conductive layer  612  and a second conductive layer  614 . The first and second conductive layers ( 612 ,  614 ) may be arranged in a face-to-face relationship. The first and second conductive layers ( 612 ,  614 ) may be separated from one another by a first dielectric layer  604 . A first patch element  605  may be in a fourth conductive layer  611 . The first conductive layer  612  and the fourth conductive layer  611  may be arranged in a face-to-face relationship separated by a second dielectric layer  603 . A second patch element  606  may be in a fifth conductive layer  613 . A stripline  602  may be in the second conductive layer  612  of the dual patch antenna  600 . A ground plane  601  may be in the second conductive layer  612 . The ground plane may include an opening or first slot  607 . The width of the slot  607  may be W ap . The width of the slot  607  may control impedance matching of the dual patch antenna  600  to the wireless electronic device  201 . In some embodiments, the slot  607  may overlap with the first patch element  605  and/or the second patch element  606 . In some embodiments, the slot  607  may overlap with the stripline  602 . In some embodiments, the slot  607  may laterally overlap with the first patch element  605  and/or the second patch element  606 . In some embodiments, the slot  607  may laterally overlap with the stripline  602 . A signal may be received and/or transmitted through the stripline  602 , causing the dual patch antenna  600  to resonate. In some embodiments, the second patch element  606  may have a different corresponding stripline  620  in a third conductive layer  619 . In some embodiments, the second patch element  606  may have a different ground plane  622  in a sixth conductive layer  621 . The ground plane  622  may include a second slot  623  in the sixth conductive layer  621 . In some embodiments, the sixth conductive layer  621  may be separated from the third conductive layer  619  by a fourth dielectric layer  624 . The sixth conductive layer  621  may be separated from the fifth conductive layer  613  by a sixth dielectric layer  625 . The two striplines  602 ,  620  may each correspond to a different patch element  605 ,  606 , respectively and thus may be used by the power divider  506  of  FIG. 5  to separately provide signals to the first patch element  605  and/or the second patch element  606 . 
     Still referring to  FIG. 6B , a power divider may be associated with the dual patch antenna  600 . The power divider is not illustrated in  FIG. 6B  for simplicity. The power divider may be internal or external to the dual patch antenna  600  but is electrically connected and/or coupled to the first stripline  602  and/or the second stripline  620 . The power divider may be configured to control a power of the signal that is applied to the first patch element  605  and/or the second patch element  606 . The first patch element  605  and/or the second patch element  606  may be configured such that a first polarization of the signal at the first patch element  605  is orthogonal to a second polarization of the signal at the second patch element  606 . 
     Still referring to  FIG. 6B , the dual patch antenna  600  may be included in a Printed Circuit Board (PCB). In some embodiments, the dual patch antenna  600  may include a PCB ground plane  616  in a seventh conductive layer  615 . The seventh conductive layer  615  may be separated from the second conductive layer  614  by a third dielectric layer  617 . The seventh conductive layer  615  may be separated from the third conductive layer  619  by a fifth dielectric layer  618 . 
     Referring to  FIG. 7A , the front side of a wireless electronic device  201 , such as a smartphone, including the dual patch antenna of  FIG. 5B ,  FIG. 6A , and/or  FIG. 6B  is illustrated. The wireless electronic device  201  may be oriented such that the front or top side of the mobile device is in a face-to-face relationship with the first conductive layer  611  of  FIG. 6A  and/or  FIG. 6B . The wireless electronic device  201  may include the dual patch antenna  600  of  FIG. 6A  and/or  FIG. 6B  with first patch element  605 . Arrow  701  illustrates the direction of polarization of the signals at the first patch element  605 . 
     Referring to  FIG. 7B , the radiation pattern associated with first patch element  605  on the front side of the wireless electronic device  201  of  FIG. 7A  is illustrated. When the first patch element  605  is excited at 15.1 GHz, an evenly distributed radiation pattern is formed around the wireless electronic device  201 . The radiation pattern around the wireless electronic device  201  exhibits little directional distortion with broad, encompassing radiation covering the space around front and back of the antenna. Although the radiation pattern of  FIG. 7B  is illustrated for the case when the first patch element  605  is excited, the presence of the second patch element  606  of  FIG. 6A  and/or  FIG. 6B  improves performance of the antenna by producing covering the space around both the front and the back of the antenna. 
     Referring to  FIG. 8A , the back side of a wireless electronic device  201 , such as a smartphone, including the dual patch antenna of  FIG. 5B ,  FIG. 6A  and/or  FIG. 6B , is illustrated. The wireless electronic device  201  may be oriented such that the back or bottom side of the mobile device is in a face-to-face relationship with the third conductive layer  613  of  FIG. 6A  and/or  FIG. 6B . The wireless electronic device  201  may include the dual patch antenna  600  of  FIG. 6A  and/or  FIG. 6B  with second patch element  606 . Arrow  801  illustrates the direction of polarization of the signals at the second patch element  606 . The polarization  701  of the first patch element  605  of  FIG. 7A  is orthogonal to the polarization  801  of the second patch element  606  of  FIG. 8A . 
     Referring to  FIG. 8B , the radiation pattern associated with second patch element  606  on the back side of the wireless electronic device  201  of  FIG. 8A  is illustrated. When the second patch element  606  is excited at 15.1 GHz, an evenly distributed radiation pattern is formed around the wireless electronic device  201 . The radiation pattern around the wireless electronic device  201  exhibits little directional distortion with broad, encompassing radiation covering the space around both the front and back of the antenna. Although the radiation pattern of  FIG. 8B  is illustrated for the case when the second patch element  606  is excited, the presence of the first patch element  605  of  FIG. 6A  and/or  FIG. 6B  improves performance of the antenna by producing covering the space around both the front and the back of the antenna. 
     Referring to  FIG. 9 , the absolute far field gain, at 15.1 GHz excitation, along a wireless electronic device including the dual patch antenna of  FIG. 6A  and/or  FIG. 6B , is illustrated. The absolute far field gain of  FIG. 9  is associated with simultaneous excitation from a power divider applied to both the first patch element  605  and the second patch element  606  of the dual patch antennas of  FIGS. 6 to 8B . In this case, approximately half the signal power was provided to excite the first patch element  605  and approximately half the signal power was provide to excite the second patch element  606 . 
     Still referring to  FIG. 9 , the axis Theta represents the y-z plane while the axis Phi represents the x-y plane around the wireless electronic device  201  of  FIGS. 7A and 7B . The absolute far field gain exhibits satisfactory gain characteristics in directions radiating from both the front face and the back face of the wireless electronic device  201 . For example, excellent gain characteristics with −35 dB isolation may be obtained in both directions of the z-axis. However, the far field gain appears to be less in both directions of the x-axis, corresponding to the sides of the mobile device. Compared to the single patch antenna of  FIGS. 3A and 3B ,  FIGS. 7A and 7B  illustrate that the dual patch antenna may provide significantly larger coverage space due to the effects of the first and second patch elements  605  and  606  and/or orthogonal polarization of signals. In other words, the single patch antenna produced a radiation pattern that was substantially directed from one direction (i.e. from one face) of the mobile device whereas the dual patch antenna produces a radiation pattern that is substantially directed from two different directions, for example, from both the front and back faces of the mobile device. 
       FIGS. 10A and 10B  illustrate the absolute far field gain using different signal feeding schemes, at 15.1 GHz excitation, along a wireless electronic device including the dual patch antenna of  FIG. 6A  and/or  FIG. 6B . As discussed in detail above, a power divider may be used to switch the signal excitation between the first and second patch elements  605  and  606 . In this example configuration, the power divider provides most of the power of the signal to the first patch element  605  of  FIG. 6A  and/or  FIG. 6B  for a first period of time, illustrated in the results of  FIG. 10A . The power divider may provide most of the power of the signal to the second patch element  606  of  FIG. 6A  and/or  FIG. 6B  for a second period of time, illustrated in the results of  FIG. 10B . Compared to the approximately equal power division of  FIG. 9 , the peak gain increases by 2 dB-3 dB when using this switching feeding scheme. The switch feeding scheme may tune the antenna to better fit channel characteristics such as periodic noise disturbances. In some embodiments, switching the feeding from the first patch element to the second patch element may be based on directional channel measurements. For example, a pilot signal from a base station may be used to determine better performance between feeding to the first patch element versus the second patch element. 
     Referring to  FIG. 11A , a dual dielectric resonator antenna (DRA)  1100  is illustrated. The dual DRA  1100  may include a first conductive layer  1112  and a second conductive layer  1114 . The first and second conductive layers ( 1112 ,  1114 ) may be arranged in a face-to-face relationship. The first and second conductive layers ( 1112 ,  1114 ) may be separated from one another by a first dielectric layer  1104 . A first flux couple may be in the first conductive layer  1112 . A second flux couple may be in a fourth conductive layer  1121 . A first dielectric block  1108  may be on the first conductive layer  1112 , opposite the first dielectric layer  1104 . A second dielectric block  1109  may be on the fourth conductive layer  1121 , opposite a fourth dielectric layer  1118 . A stripline  1102  may be in the second conductive layer  1114  of the dual DRA  1100 . A ground plane  1101  may be in the second conductive layer  1112 . The ground plane  1101  may include an opening or slot  1107 . The width of the slot  1107  may be W ap . In some embodiments, the slot  1107  may laterally overlap the first dielectric block  1108  and/or the second dielectric block  1109 . In some embodiments, the slot  1107  may overlap the stripline  1102 . A signal may be received and/or transmitted through the stripline  1102 , causing the dual DRA  1100  to resonate. Some embodiments may include a ground plane  1120  including a second slot  1110  in the fourth conductive layer  1121 . In some embodiments, the first dielectric block  1108  may overlap the first slot  1107  and/or the second dielectric block  1109  may overlap the second slot  1110 . In some embodiments, factors such as the relative permittivity of the first dielectric block  1108  and/or the second dielectric block  1109  may affect the electromagnetic properties of the dual DRA antenna  1100  and/or subsequently affect the antenna performance. In some embodiments, the first radiating element  501  of  FIG. 5B  may include a first flux couple and/or the first dielectric block  1108  of  FIG. 11A . Similarly, the second radiating element  502  of  FIG. 5B  may include a second flux couple and/or the second dielectric block  1109  of  FIG. 11A . The dual DRA  1100  of  FIG. 11A  provides similar performance results as illustrated in  FIGS. 7B, 8B, 9, 10A , and/or  10 B. In some embodiments, the dual DRA  1100  of  FIG. 11A  may provide better performance with wider bandwidth when compared to the dual path antenna  600  of  FIG. 6A  and/or  FIG. 6B . 
     Still referring to  FIG. 11A , a power divider may be associated with the DRA  1100 . The power divider is not illustrated in  FIG. 11A  for simplicity. The power divider may be internal or external to the DRA  1100  but is electrically connected and/or coupled to the stripline  1102 . The power divider may be configured to control a power of the signal that is applied to the first dielectric block  1108  and/or the second dielectric block  1109 . The first dielectric block  1108  and/or the second dielectric block  1109  may be configured such that a first polarization of the signal at the first dielectric block  1108  is orthogonal to a second polarization of the signal at the second dielectric block  1109 . 
     Referring to  FIG. 11B , a dual dielectric resonator antenna (DRA)  1100  is illustrated. The dual DRA  1100  may include a first conductive layer  1112  and a second conductive layer  1114 . The first and second conductive layers ( 1112 ,  1114 ) may be arranged in a face-to-face relationship. The first and second conductive layers ( 1112 ,  1114 ) may be separated from one another by a first dielectric layer  1104 . A first flux couple may be in the first conductive layer  1112 . A second flux couple may be in a fourth conductive layer  1121 . A first dielectric block  1108  may be on the first conductive layer  1112 , opposite the first dielectric layer  1104 . A second dielectric block  1109  may be on the fourth conductive layer  1121 , opposite a fourth dielectric layer  1118 . A stripline  1102  may be in the second conductive layer  1114  of the dual DRA  1100 . A ground plane  1101  may be in the second conductive layer  1112 . The ground plane  1101  may include an opening or slot  1107 . The width of the slot  1107  may be W ap . In some embodiments, the slot  1107  may laterally overlap the first dielectric block  1108  and/or the second dielectric block  1109 . In some embodiments, the slot  1107  may overlap the stripline  1102 . A signal may be received and/or transmitted through the stripline  1102 , causing the dual DRA  1100  to resonate. Some embodiments may include a ground plane  1120  including a second slot  1110  in the fourth conductive layer  1121 . In some embodiments, the first dielectric block  1108  may overlap the first slot  1107  and/or the second dielectric block  1109  may overlap the second slot  1110 . In some embodiments, a second stripline  1120  may be included in a third conductive layer  1119 . The third conductive layer  1119  may be separated from the sixth conductive layer  1121  by a fourth dielectric layer  1124 . 
     Still referring to  FIG. 11B , the dual DRA  1100  may be included in a Printed Circuit Board (PCB). In some embodiments, the dual DRA  1100  may include a PCB ground plane  1116  in a seventh conductive layer  1115 . The seventh conductive layer  1115  may be separated from the second conductive layer  1114  by a third dielectric layer  1117 . The seventh conductive layer  1115  may be separated from the third conductive layer  1119  by a fifth dielectric layer  1118 . 
     In some embodiments, factors such as the relative permittivity of the first dielectric block  1108  and/or the second dielectric block  1109  may affect the electromagnetic properties of the dual DRA antenna  1100  and/or subsequently affect the antenna performance. In some embodiments, the first radiating element  501  of  FIG. 5B  may include a first flux couple and/or the first dielectric block  1108  of  FIG. 11B . Similarly, the second radiating element  502  of  FIG. 5B  may include a second flux couple and/or the second dielectric block  1109  of  FIG. 11B . The dual DRA  1100  of  FIG. 11B  provides similar performance results as illustrated in  FIGS. 7B, 8B, 9, 10A , and/or  10 B. In some embodiments, the dual DRA  1100  of  FIG. 11B  may provide better performance with wider bandwidth when compared to the dual path antenna  600  of  FIG. 6A  and/or  FIG. 6B . 
     Still referring to  FIG. 11B , a power divider may be associated with the DRA  1100 . The power divider is not illustrated in  FIG. 11B  for simplicity. The power divider may be internal or external to the DRA  1100  but is electrically connected and/or coupled to the stripline  1102 . The power divider may be configured to control a power of the signal that is applied to the first dielectric block  1108  and/or the second dielectric block  1109 . The first dielectric block  1108  and/or the second dielectric block  1109  may be configured such that a first polarization of the signal at the first dielectric block  1108  is orthogonal to a second polarization of the signal at the second dielectric block  1109 . 
       FIGS. 12A and 12B  illustrate a wireless electronic device  201  such as a smartphone including an array of dual patch antennas of  FIG. 6A  and/or  FIG. 6B . Referring to  FIG. 12A , the front side of a wireless electronic device  201  including an array of first patch antenna elements  605   a - 605   h  is illustrated. The polarization of the signals at first patch antenna elements  605   a - 605   h  is indicated by arrow  1201 . Now referring to  FIG. 12B , the back side of a wireless electronic device  201  including an array of second patch elements  606   a - 606   h  is illustrated. The polarization of the signals at second patch antenna elements  606   a - 606   h  is indicated by arrow  1202 . In some embodiments, polarization  1201  may be orthogonal to polarization  1202 . Although  FIGS. 12A and 12B  are described in the context of the dual patch antenna of  FIG. 6A  and/or  FIG. 6B  as a non-limiting example, the array may include the first and second radiating elements of  FIGS. 5A and 5B , and/or the first and second flux couples and first and second dielectric blocks of the DRA antenna of  FIG. 11A , according to some embodiments. 
       FIGS. 13A-13C  illustrate the radiation pattern around the wireless electronic device  201 , including a dual patch array antenna of  FIGS. 12A and 12B . Referring to  FIG. 13A , when the dual patch array antenna is excited, an evenly distributed radiation pattern is formed around the wireless electronic device  201 . The radiation pattern around the wireless electronic device  201  exhibits little directional distortion along the z-axis with broad, encompassing radiation, symmetrically covering the space around the front side and back side of the wireless electronic device  201 . Referring to  FIGS. 13B and 13C , although a broad radiation pattern is exhibited in  FIG. 13A  with respect to the front and back faces of the wireless electronic device  201 , poor gain characteristics and distortion may be present in the direction of the x-axis. 
     The dual patch antenna and/or the dual DRA described herein may be suitable for use at millimeter band radio frequencies in the electromagnetic spectrum, for example, from 10 GHz to 300 GHz. In some embodiments, if may be desirable for the wireless electronic device  201  to transmit and/or receive signals in the cellular band of 850 to 1900 MHz. Referring now to  FIG. 14 , a wireless electronic device  201  including a metal ring antenna  1402  is illustrated. The metal ring antenna may extend along an outer edge of the PCB  109 . The metal ring antenna may be spaced apart and electrically isolated from the PCB  109 . The metal ring antenna  1402  may be coupled to PCB  109  through grounding components  1403  and  1404 . The metal ring antenna may be configured to resonate at a frequency in the cellular band of 850 to 1900 MHz that is different from the millimeter band of the dual patch antenna and/or the dual DRA. 
     Referring to  FIG. 15 , a wireless electronic device  201  with the metal ring antenna  1402  of  FIG. 14  as well as the dual patch array antenna of  FIGS. 12A and 12B  is illustrated.  FIG. 15  illustrates a front view of the mobile device and thus illustrates first patch antenna elements  605   a - 605   h . Corresponding second patch antenna elements may be located on the back side of the wireless electronic device  201 . Although  FIG. 15  is described in the context of the dual patch antenna array of  FIGS. 12A and 12B  as a non-limiting example, the array may include the first and second radiating elements of  FIGS. 5A and 5B , and/or the first and second flux couples of  FIG. 11A  and/or the first and second dielectric blocks of the DRA antenna of  FIG. 11A , according to some embodiments. 
     Referring to  FIG. 16 , a wireless electronic device with a metal ring antenna as well as a dual patch Multiple Input and Multiple Output (MIMO) array antenna is illustrated.  FIG. 16  illustrates the dual patch array antenna of  FIG. 15 , with an array dual patch antennas configured in subarrays for MIMO operation. For example, patch antenna elements  605   a  to  605   d  comprise MIMO subarray  1601  whereas patch antenna elements  605   e  to  605   h  comprise MIMO subarray  1602 . Although not illustrated in  FIG. 16 , corresponding second patch antenna elements  606   a  to  606   h  may be present on the back side of the wireless electronic device  201 . Arrows  1603  indicate the direction of polarization of MIMO subarray  1601  whereas arrows  1604  indicates the direction of polarization of MIMO subarray  1602 . Corresponding second patch antenna elements  606   a  to  606   d  on the back of the wireless electronic device  201  and associated with MIMO subarray  1601 , may have a direction of polarization that is orthogonal to the direction indicated by  1603 . Likewise, corresponding second patch antenna elements  606   e  to  606   h  on the back of the wireless electronic device  201  and associated with MIMO subarray  1602 , may have a direction of polarization that is orthogonal to the direction indicated by  1604 . Although  FIG. 16  is described in the context of the dual patch antenna of  FIG. 6A  and/or  FIG. 6B  as a non-limiting example, the MIMO array antenna may include the first and second radiating elements of  FIGS. 5A and 5B , and/or the first and second flux couples of  FIG. 11A  and/or the first and second dielectric blocks of the DRA antenna of  FIG. 11B , according to some embodiments. 
     Referring to  FIG. 17A , the radiation patterns around the wireless electronic device  201  for the dual patch MIMO subarray  1601  of  FIG. 16  is illustrated. Arrow  1701  indicates the polarization of the first patch antenna elements in the dual patch MIMO subarray  1601  and arrow  1702  indicates the polarization of the second patch antenna elements in the dual patch MIMO subarray  1601 . The radiation pattern around the wireless electronic device  201  exhibits little directional distortion on the z-axis with broad, encompassing radiation covering the space around the front side and back side of the wireless electronic device  201 . 
     Referring to  FIG. 17B , the radiation patterns around the wireless electronic device  201  for dual patch MIMO subarray  1602  of  FIG. 16  is illustrated. Arrow  1703  indicates the polarization of the first patch antenna elements in the dual patch MIMO subarray  1602  and arrow  1704  indicates the polarization of the second patch antenna elements in the dual patch MIMO subarray  1602 . The radiation pattern around the wireless electronic device  201  exhibits little directional distortion on the z-axis with broad, encompassing radiation covering the space around the front side and back side of the wireless electronic device  201 . 
     Referring to  FIG. 18 , a wireless electronic device  1800  such as a cell phone including one or more antennas according to any of  FIGS. 1 to 17B  is illustrated. The wireless electronic device  1800  may include a processor  1801  for controlling the transceiver  1802 , power divider  1807 , and/or one or more antennas  1808 . The one or more antenna  1808  may include the patch antenna  600  of  FIG. 6A  and/or  FIG. 6B , the DRA  1100  of  FIG. 11A  and/or  FIG. 11B , and/or the metal ring antenna  1402  of  FIGS. 14 to 16 . The wireless electronic device  1800  may include a display  1803 , a user interface  1804 , and/or memory  1806 . In some embodiments, the power divider  1807  may be part of an electronic circuit package  503  of  FIG. 5A . 
     The above discussed antenna structures for millimeter band radio frequency communication with dual radiating elements may produce uniform radiation patterns with respect to the front face and back face of a mobile device. The dual patch antennas and/or the dual DRA antenna may control the radiation pattern of the antenna. A collection of the dual radiating elements arranged in an array may provide MIMO communication in addition to omni-directional radiation patterns. In some embodiments, the polarization of the first radiating element of the dual radiating element antenna may be orthogonal to the second radiating element, improving far field gain. In some embodiments, a power divider may be used in conjunction with dual radiating element antenna to improve coverage of the antenna. In some embodiments, a metal ring antenna may be used in conjunction with the dual radiating element antenna for cellular frequency communication. The described inventive concepts create antenna structures with omni-directional radiation, wide bandwidth, and/or multi-frequency use. 
     Antenna Including an Array of Dual Radiating Elements and Power Dividers 
     Various wireless communication applications may use a dual radiating element antenna. The dual radiating element antenna may be suitable for use in the millimeter band radio frequencies in the electromagnetic spectrum from 10 GHz to 300 GHz. The dual radiating element antenna may provide radiation beams that are quite broad. A potential disadvantage of dual radiating element antennas is that the path loss may be high. For example, if a dual radiating element antenna is used in a mobile device, the radiation pattern around the mobile device may not have enough peak gain for the desired application. 
     Various embodiments described herein may arise from a recognition that a single dual radiating element antenna may be improved by adding other dual radiating element antennas to produce a dual radiating element antenna array design. The array of dual radiating element antennas may improve the antenna performance by producing high gain signals that cover the three-dimensional space around the mobile device. Further performance improvements may be obtained by adding a plurality of power dividers to control power to various elements in the array of dual radiating element antennas based on signal conditions. 
       FIGS. 1 to 18  have been discussed above and include embodiments related to antennas with dual radiating elements.  FIGS. 19 to 34  will now discuss antennas including an array of dual radiating elements and power dividers. Referring now to  FIG. 19 , a wireless electronic device  1901  including an array of dual radiating element antennas is illustrated. The top side of the wireless electronic device  1901  is illustrated, which includes the first radiating elements  1902   a  to  1902   h . Corresponding seconding radiating elements are located on the opposite, bottom side of the wireless electronic device  1901  and are not illustrated in  FIG. 19 . 
     Referring now to  FIG. 20 , a wireless electronic device  1901  including a plurality of dual radiating element antennas  2002  and a plurality of power dividers  2008  is illustrated. Each of the dual radiating element antennas  2002  may include a first radiating element  2004  and a second radiating element  2006 . In some embodiments, the first radiating element  2004  and/or the second radiating element  2006  may include a patch element. In some embodiments, the first radiating element  2004  and/or the second radiating element  2006  may include a dielectric block on a conductive layer. The plurality of dual radiating element antennas  2002  may be arranged in an array  2001  of dual radiating element antennas. The plurality of power dividers  2008  may be arranged in an array  2005  of power dividers. 
     Still referring to  FIG. 20 , a signal  2010  may be input into a power divider  2008 . The power divider  2008  may be configured to divide a power of the signal  2010  into a first portion of the power and/or a second portion of the power. The power divider  2008  may apply the signal  2010  at the first portion of the power  2012  to the first radiating element  2004  and/or the power divider  2008  may apply the signal  2010  at the second portion of the power  2014  to the second radiating element  2006 . In some embodiments, the power divider may divide the power evenly between the first radiating element  2004  and the second radiating element  2006 , i.e. 50% of the power may be applied to the first radiating element  2004  and 50% of the power may be applied the second radiating element  2006 . In some embodiments, the portions of power may be divided unevenly by the power divider, i.e. a higher portion of the power may be applied to the first radiating element  2004  or a higher portion of the power may be applied to the second radiating element  2006 . In some embodiments, all of the power (i.e. 100%) may be applied to the first radiating element  2004  or all of the power (i.e. 100%) may be applied to the second radiating element  2006 . 
     In some embodiments, a respective one of the plurality of dual radiating antennas  2002  may be configured such that a first polarization of the signal at the first portion of the power  2012  applied to the first radiating element  2004  is orthogonal to a second polarization of the signal at the second portion of the power  2014  applied to the second radiating element  2006 . In some embodiments, a third polarization of a respective first radiating element  2004  of a first one of the plurality of dual radiating antennas may be orthogonal to a fourth polarization of a respective first radiating element  2004  of a second one of the plurality of dual radiating antennas that is adjacent the first one of the plurality of dual radiating antennas. A fifth polarization of a respective second radiating element  2006  of the first one of the plurality of dual radiating antennas may be orthogonal to a sixth polarization of a respective second radiating element  2006  of the second one of the plurality of dual radiating antennas that is adjacent the first one of the plurality of dual radiating antennas. In some embodiments, the third polarization may be orthogonal to the fifth polarization, and/or the fourth polarization may be orthogonal to the sixth polarization. 
     Referring now to  FIG. 21 , dual radiating element antennas and power dividers along with a controller for diversity combining systems are illustrated. Diversity combining is a technique applied to combine the multiple received signals of a diversity reception device into a single improved signal. For this diversity combining system, the same input signal  2110  is received at multiple power dividers  2102 . The power dividers  2102  divide the power of the input signal  2110  between the first radiating element  2106  and the second radiating element  2108 . In some embodiments, the power divider may be configured and/or controlled by a controller  2104 . The controller  2104  may generate one or more control signals  2105  that control the amount and/or portion of the power of the input signal  2110  that is applied by the power divider to the first radiating element  2106  and the second radiating element  2108 . The control signal  2105  may provide an indication of a value of the first portion of the power  2012  and/or the second portion of the power  2014  of the input signal  2110  that is applied by the power divider to the first radiating element  2106  and the second radiating element  2108 . 
     Referring now to  FIG. 22 , a plurality of dual radiating element antennas  2206   a ,  2206   b  and power dividers  2204   a ,  2204   b  for Multiple Input and Multiple Output (MIMO) systems are illustrated. For the MIMO system, signal A    2212  may be associated with dual radiating element antenna  2206   a  and signal B    2214  may be associated with dual radiating element antenna  2206   b . Signal A    2212  and signal B    2214  may be subjected to different phases and/or channel characteristics. Signal A    2212  is input into power divider  2204   a  and may be different from input signal B , which is input into power divider  2204   b . Power divider  2204   a  may divide the power of the signal A    2212  and apply signal A    2212  at a first portion of the signal power  2216  to the first radiating element  2208   a  and apply signal A    2212  at a second portion of the signal power  2218  to the second radiating element  2210   a . Similarly, power divider  2204   b  may divide the power of the signal B    2214  and apply signal B    2214  at a first portion of the signal power  2220  to the first radiating element  2208   b  and apply signal B    2214  at a second portion of the signal power  2222  to the second radiating element  2210   b.    
     Referring now to  FIG. 23 , an embodiment of a power divider  2008  of  FIG. 20  is illustrated in detail. The power divider  2008  may be coupled to an input signal P 1  and may provide outputs P 2  and P 3 . In some embodiments, the power divider  2008  may be the shape of concentric rings with a length of λ/4 on a top half of the outer ring between the input P 1  and output P 2  and a length of λ/4 on a bottom half of the outer ring between the input P 1  and output P 3 . In some embodiments, the inner ring may be a length of λ/2. An impedance matching element 2·Z 0  may be coupled to P 2  and/or P 3  near the inner ring. In some embodiments, the outer ring may have an impedance characteristic sqrt(2)*Z 0 . 
       FIGS. 24A-24C  illustrate the absolute far field gain at different points along the power divider of  FIG. 23 . Referring now to  FIG. 24A , the absolute far field gain at 15.1 GHz excitation at a first radiating element of a dual radiating element antenna, of a signal at output P 2  of the power divider  2008  of  FIG. 23  is illustrated. Referring now to  FIG. 24B , the absolute far field gain at 15.1 GHz excitation at a second radiating element of a dual radiating element antenna, of a signal at the output P 3  of the power divider  2008  of  FIG. 23  is illustrated. Referring now to  FIG. 24C , the overall absolute far field gain at 15.1 GHz excitation of a dual radiating element antenna is illustrated. 
     Referring now to  FIG. 25 , a switch  2502  for selecting different feeding schemes is illustrated. In some embodiments, different antenna feeding schemes may be used based on the channel situation. In other words, a feeding scheme may be selected to tune the antenna pattern in response to the channel conditions. Tuning the antenna pattern may include selecting one or more dual radiating element antennas for excitation by the input signals and/or selecting one or more first and/or second radiating elements for excitation by the input signals. In some embodiments, the switch  2502  may be integrated as part of the power divider of  FIGS. 20 to 22 . In some embodiments, the switch  2502  may be part of the controller  2104  of  FIG. 21  and/or controller  2202  of  FIG. 22 . A control signal  2506  from the controller of  2104  of  FIG. 21  and/or from controller  2202  of  FIG. 22  may control operation of switch  2502 . The switch  2502  may be configured to select output  2510  and/or  2512  to controller the antenna feeding scheme of the wireless electronic device  2504 . For example, selecting one or more dual radiating element antennas for excitation by the input signals may be controlled by input  2514  to the wireless electronic device  2504 . Selecting one or more first and/or second radiating elements for excitation by the input signals may be controlled by input  2516  to the wireless electronic device  2504 . 
       FIGS. 26A-26B  illustrate the absolute far field gain for different feeding schemes using the switch of  FIG. 25 . In some embodiments, switch  2502  of  FIG. 25  may be configured as a default feeding scheme to feed all elements in an array of dual radiating element antennas. Referring to  FIG. 26A , the absolute far field gain is illustrated for a default feeding scheme which includes exciting first and second radiating elements of one or more dual radiating element antennas. In some embodiments, the switch  2502  of  FIG. 25  of may be configured to selectively feed the first radiating element of one or more dual radiating element antennas. Referring to  FIG. 26B , the absolute far field gain is illustrated for the case of selectively feeding the first radiating element of one or more dual radiating element antennas. In some embodiments, the switch  2502  of  FIG. 25  may be configured to selectively feed the second radiating element of one or more dual radiating element antennas. Referring to  FIG. 26C , the absolute far field gain is illustrated for the case of selectively feeding the second radiating element of one or more dual radiating element antennas. 
       FIG. 27  illustrates antenna coverage provided by a dual radiating element antenna array of  FIG. 19 . A wireless electronic device  2702 , such as a mobile phone, may include a dual radiating element antenna array. Use of an array of dual radiating element antennas may increase the overall antenna gain when compared to a single dual radiating element antenna. In some embodiments, the high gain may translate into a relatively narrow beam width of the antenna coverage area  2704 , reducing overall coverage around the mobile device. A beam steering function may achieved by use of a phased array of dual radiating element antennas, as will be illustrated in  FIGS. 28 to 31B . A phased array may maintain a good signal link when incoming signals arrive from different angles. 
       FIG. 28  illustrates signals received by dual radiating element antenna with subarrays  2808  and  2810  in a wireless electronic device  2702 . Referring to  FIG. 28 , antenna subarrays  2808  and  2810  may be tuned to different channel characteristics from different base stations  2804  and  2806 . For example, antenna subarray  2808  may be tuned to signals received from base station  2804  whereas antenna subarray  2810  may be tuned to signals received from base station  2806 . Similarly, antenna subarrays  2808  and  2810  may be tuned for transmission to base stations  2804  and  2806 , respectively. Tuning of antenna subarrays  2808  and  2810  may include controlling power to the first and/or second radiating elements and/or selecting one or more dual radiating element antennas in the respective antenna subarray. Base stations  2804  and/or  2806  may include various types of base stations such as macro-cell base stations, microcell base stations, pico-cell base stations, and/or femto-cell base stations. 
       FIG. 29A  illustrates a dual patch MIMO antenna array  2901 . The dual patch MIMO antenna array  2901  may include a first dual patch MIMO antenna including a first patch  2902  and a second patch  2904 . The dual patch MIMO antenna array  2901  may include a second dual patch MIMO antenna including a first patch  2906  and a second patch  2908 . In some embodiments, the first patches  2902  and  2906  may correspond to a front face of the wireless electronic device  1901  of  FIG. 19 , such as a mobile phone. The signal applied to the first patch  2902  may be orthogonal to the signal applied to the second patch  2904 . Similarly, the signal applied to the first patch  2906  may be orthogonal to the signal applied to the second patch  2908 . Moreover, in some embodiments, the signal applied to the first patch  2902  of a first dual patch MIMO antenna may be orthogonal to a signal applied to an adjacent first patch  2906  of a second dual patch MIMO antenna and/or the signal applied to the second patch  2904  of a second dual patch MIMO antenna may be orthogonal to a signal applied to an adjacent second patch  2908  of a second dual patch MIMO antenna. 
       FIGS. 29B to 29E  illustrate radiation patterns attributed to various elements of the wireless electronic device  1901 , including the dual patch MIMO antenna array of  FIG. 29A . Referring now to  FIG. 29B , the radiation pattern attributed to the second patch  2908  of  FIG. 29A  is illustrated. The radiation pattern is directed towards the back face of the wireless electronic device  1901 . Referring now to  FIG. 29C , the radiation pattern attributed to the first patch  2902  of  FIG. 29A  is illustrated. The radiation pattern is directed towards the front face of the wireless electronic device  1901 . The black arrow of  FIG. 29C  illustrates the polarization of the signals at the first patch  2902 . Referring now to  FIG. 29D , the radiation pattern attributed to the first patch  2906  of  FIG. 29A  is illustrated. The radiation pattern is directed towards the front face of the wireless electronic device  1901 . The black arrow of  FIG. 29D  illustrates the polarization of the signals at the first patch  2906 . Referring now to  FIG. 29E , the radiation pattern attributed to the second patch  2904  of  FIG. 29A  is illustrated. The radiation pattern is directed towards the back face of the wireless electronic device  1901 . The black arrow of  FIG. 29E  illustrates the polarization of the signals at the second patch  2904 . 
       FIG. 30A  illustrates a dual patch MIMO antenna array  2901  including power dividers associated with respective dual patch antennas. The dual patch MIMO antenna array  2901  may include a first dual patch MIMO antenna including a first patch  2902  and a second patch  2904 . The dual patch MIMO antenna array  2901  may include a second dual patch MIMO antenna including a first patch  2906  and a second patch  2908 . In some embodiments, the signal applied to the first patch  2902  may be orthogonal to the signal applied to the second patch  2904 . Similarly, the signal applied to the first patch  2906  may be orthogonal to the signal applied to the second patch  2908 . Moreover, in some embodiments, the signal applied to the first patch  2902  of a first dual patch MIMO antenna may be orthogonal to a signal applied to an adjacent first patch  2906  of a second dual patch MIMO antenna. A power divider  3002  may be associated with the first dual patch MIMO antenna and may be configured to divide a power of a signal  3001  into a first portion of the power and a second portion of the power. The power divider  3002  may apply the signal  3001  at the first portion of the power to the respective first patch  2902  and to apply the signal at the second portion of the power to the respective second patch  2904 . A power divider  3004  may be associated with the second dual patch MIMO antenna and may be configured to divide a power of a signal  3003  into a first portion of the power and a second portion of the power. The power divider  3004  may apply the signal  3003  at the first portion of the power to the respective first patch  2906  and to apply the signal at the second portion of the power to the respective second patch  2908 . 
       FIGS. 30B and 30C  illustrate the radiation pattern around the wireless electronic device  1901 , including a dual patch MIMO antenna array  2901  and power dividers  3002  and  3004  of  FIG. 30A . Referring now to  FIG. 30B , the radiation pattern associated with a first dual patch antenna including the first patch  2902  and second patch  2904  is illustrated. The radiation pattern spans both the front face and back face of the wireless electronic device  1902  since the power divider  3002  apply the signal  3001  at the first portion of the power to the first patch  2902  and/or applies the signal  3001  at the second portion of the power to the second patch  2904 . The black arrows illustrate the polarization of the signals at the first patch  2902  and the second patch  2904 . Referring now to  FIG. 30C , the radiation pattern associated with a second dual patch antenna including the first patch  2906  and second patch  2908  is illustrated. The radiation pattern spans both the front face and back face of the wireless electronic device  1902  since the power divider  3004  apply the signal  3003  at the first portion of the power to the first patch  2906  and/or applies the signal  3003  at the second portion of the power to the second patch  2908 . The black arrows illustrate the polarization of the signals at the first patch  2906  and the second patch  2908 . 
       FIGS. 31A and 31B  illustrate dual patch MIMO antenna subarrays  3102  and  3104  on a wireless electronic device  1901 . Referring now to  FIG. 31A , dual patch MIMO antenna subarrays for diversity combining applications are illustrated. A signal  3101  may be input into the first subarray  3102 . The signal  3101  may be applied to one or more of the dual patch antennas in the first subarray  3102 . In some embodiments, the signal  3101  may be applied to a first patch  3106   a  and/or a second patch  3106   b  of a first dual patch antenna, a first patch  3108   a  and/or a second patch  3108   b  of a second dual patch antenna, a first patch  3110   a  and/or a second patch  3110   b  of a third dual patch antenna, and/or a first patch  3112   a  and/or a second patch  3112   b  of a fourth dual patch antenna of the first subarray  3102 . Likewise, a signal  3103  may be applied to one or more of the dual patch antennas in the second subarray  3104 . In some embodiments, the signal  3103  may be applied to a first patch  3114   a  and/or a second patch  3114   b  of a first dual patch antenna, a first patch  3116   a  and/or a second patch  3116   b  of a second dual patch antenna, a first patch  3118   a  and/or a second patch  3118   b  of a third dual patch antenna, and/or a first patch  3120   a  and/or a second patch  3120   b  of a fourth dual patch antenna of the second subarray  3104 . 
     Referring now to  FIG. 31B , dual patch MIMO antenna subarrays  3102  and  3104  for diversity combining applications including power dividers are illustrated. The two subarrays  3102  and  3104  may be controlled separately based on signal characteristics, reducing power consumption and/or increasing coverage efficiently. For example, signal  3122  may be applied to subarray  3102  and/or signal  3124  may be applied to subarray  3104 . Subarray  3102  and  3104  may correspond to subarrays  2808  and  2810  of  FIG. 28  and may receive signals from different base stations and/or on channels with different propagation characteristics. 
     Still referring to  FIG. 31B , in some embodiments, a signal  3122  may be applied to power dividers  3107 ,  3109 ,  3111 , and/or  3113  of subarray  1302 . Power divider  3107  may divide the power of the signal  3122  and apply the signal at the first portion of the power to the first patch  3106   a  and/or apply the signal at the second portion of the power to the second patch  3106   b . Power divider  3109  may divide the power of the signal  3122  and apply the signal at the first portion of the power to the first patch  3108   a  and/or apply the signal at the second portion of the power to the second patch  3108   b . Power divider  3111  may divide the power of the signal  3122  and apply the signal at the first portion of the power to the first patch  3110   a  and/or apply the signal at the second portion of the power to the second patch  3110   b . Power divider  3113  may divide the power of the signal  3122  and apply the signal at the first portion of the power to the first patch  3112   a  and/or apply the signal at the second portion of the power to the second patch  3112   b.    
     Still referring to  FIG. 31B , in some embodiments, a signal  3124  may be applied to power dividers  3115 ,  3117 ,  3119 , and/or  3121  of subarray  1304 . Power divider  3115  may divide the power of the signal  3124  and apply the signal at the first portion of the power to the first patch  3114   a  and/or apply the signal at the second portion of the power to the second patch  3114   b . Power divider  3117  may divide the power of the signal  3124  and apply the signal at the first portion of the power to the first patch  3116   a  and/or apply the signal at the second portion of the power to the second patch  3116   b . Power divider  3119  may divide the power of the signal  3124  and apply the signal at the first portion of the power to the first patch  3118   a  and/or apply the signal at the second portion of the power to the second patch  3118   b . Power divider  3121  may divide the power of the signal  3124  and apply the signal at the first portion of the power to the first patch  3120   a  and/or apply the signal at the second portion of the power to the second patch  3120   b.    
       FIG. 32  illustrates operations that may be performed by a controller for the dual patch MIMO antenna subarrays of  FIGS. 20-22, 31A and/or 31B . Referring to block  3202 , a subarray of a dual patch MIMO antenna may transmit and/or receive a signal with an omni-directional pattern and/or a random phase. At block  3204 , the wave direction and/or signal strength of an received signal may be detected. The received signal may be evaluated to determine the quality of the signal strength. The quality of the signal may be determined in relative terms such as “weak signal”, “good signal” and/or “very good signal”. In some embodiments the quality of the signal may be based on thresholds for the signal strength. Thresholds may be fixed and/or vary over time and may be absolute thresholds or a percentage of a given quality. If the received signal is determined to be a “weak signal”, at block  3206 , the dual patch MIMO antenna may use beam forming mode, thus utilizing one or more subarrays and first and/or second radiating elements. In some embodiments, this beam forming mode may provide 9 dB of gain for a four antenna array, compared to a conventional antenna. If the received signal is determined to be a “good signal”, at block  3208 , the dual patch MIMO antenna may use a single subarray with a random phase pattern. In some embodiments, use of a single subarray may provide a 3 dB gain and/or 50% savings in power, when compared to a conventional antenna. If the received signal is determined to be a “very good signal”, at block  3210 , the dual patch MIMO antenna may use a single subarray with a single radiating element. In some embodiments, use of a single subarray with a single radiating element may provide a power savings of 87.5%, compared to a conventional antenna. 
       FIG. 33  illustrates a flowchart for determining modes of operating any of the antennas of  FIGS. 19-22, 29A, 30A, 31A , and/or  31 B, according to various embodiments of the present inventive concepts. Referring now to  FIG. 33 , one or more signals may be received at a plurality of dual radiating antennas, at block  3302 . At block  3304 , the signal strength of the received signals may be compared to a first threshold. If the signal strength is not greater than the first threshold, beam forming mode may be used by the antennas at block  3306 . Specifically, beam forming mode may configure each of the power dividers of  FIGS. 19-22, 29A, 30A and/or 31B  for the first subarray to provide the signal at a first portion of the power of the signal that is greater than zero, and configure each of the power dividers of the second subarray to provide the signal at a second portion of the power of the signal that is greater than zero. 
     Still referring to  FIG. 33 , at block  3304 , if the signal strength is greater than the first threshold, the signal strength may be evaluated with respect to a second threshold at block  3308 . If the signal strength is not greater than the second threshold, subarray switching mode may be used by the antennas at block  3310 . Subarray switching mode may include use of one subarray of the plurality of dual radiating antennas and/or may include using the first radiating elements or the second radiating elements of the subarray of dual radiating antennas. Specifically, the power dividers of  FIGS. 19-22, 29A, 30A and/or 31B  for the first subarray may be each configured to provide all of the power of the signal to the first radiating element and the power dividers of the second subarray may be each configured to provide all of the power of the signal to the second radiating element, or the power dividers of the first subarray may be each configured to provide all of the power of the signal to the second radiating element and/or the power dividers of the second subarray may be each configured to provide all of the power of the signal to the first radiating element. 
     Still referring to  FIG. 33 , at block  3308 , if the signal strength is greater than the second threshold, single element mode may be used by the antennas at block  3312 . Single element mode may include using a first or second radiating element of one dual radiating antenna. More specifically, in single element mode, a selected one of the power dividers of the first subarray or the power dividers of the second subarray may be configured to provide all of the power of the signal to a respective first radiating element and zero power to a respective second radiating element of a respective dual radiating antenna or may be configured to provide all of the power of the signal to a respective second radiating element and zero power to a respective first radiating element of a respective dual radiating antenna. In single element mode, the remaining ones of the power dividers of the first subarray and the power dividers of the second subarray, exclusive of the selected one, may be configured to provide zero power to respective first radiating elements and respective second radiating elements of respective dual radiating antennas. 
       FIG. 34  illustrates a dual patch antenna array of any of  FIGS. 19-22, 29A, 30A, 31A , and/or  31 B. Referring now to  FIG. 34 , four dual radiating antennas  3400   a ,  3400   b ,  3400   c , and  3400   d , configured in a dual patch antenna array in a wireless electronic device  1901  of any of  FIGS. 19-22, 29A, 30A, 31A , and/or  31 B are illustrated. Dual radiating antenna  3400   a  will now be described in detail. Dual radiating antennas  3400   b ,  3400   c , and  3400   d  are similar in structure to  3400   a  and will not be described in detail in the interest of brevity. 
     The first dual patch antenna  3400   a  may include a first conductive layer  3412  and a second conductive layer  3414 . The first and second conductive layers ( 3412 ,  3414 ) may be arranged in a face-to-face relationship. The first and second conductive layers ( 3412 ,  3414 ) may be separated from one another by a first dielectric layer  3404 . A first patch element  3405   a  may be in a fourth conductive layer  3411 . The first conductive layer  3412  and the fourth conductive layer  3411  may be arranged in a face-to-face relationship separated by a second dielectric layer  3403 . A second patch element  3406   a  may be in a fifth conductive layer  3413 . A stripline  3402   a  may be in the second conductive layer  3412  of the first dual patch antenna  3400   a . A ground plane  3401  may be in the second conductive layer  3412 . The ground plane may include an opening or first slot  3407   a . The width of the slot  3407   a  may be W ap . The width of the slot  3407   a  may control impedance matching of the dual patch antenna  3400   a  to the wireless electronic device  1901 . In some embodiments, the slot  3407   a  may overlap with the first patch element  3405   a  and/or the second patch element  3406   a . In some embodiments, the slot  3407   a  may overlap with the stripline  3402   a . In some embodiments, the slot  3407   a  may laterally overlap with the first patch element  3405   a  and/or the second patch element  3406   a . In some embodiments, the slot  3407   a  may laterally overlap with the stripline  3402   a . A signal may be received and/or transmitted through the stripline  3402   a , causing the first dual patch antenna  3400   a  to resonate. In some embodiments, the second patch element  3406   a  may have a different corresponding stripline  3420   a  in a third conductive layer  3419 . In some embodiments, the second patch element  3406   a  may have a different ground plane  3422  in a sixth conductive layer  3421 . The ground plane  3422  may include a second slot  3423   a  in the sixth conductive layer  3421 . In some embodiments, the sixth conductive layer  3421  may be separated from the third conductive layer  3419  by a fourth dielectric layer  3424 . The sixth conductive layer  3421  may be separated from the fifth conductive layer  3413  by a sixth dielectric layer  3425 . The two striplines  3402   a ,  3420   a  may each correspond to a different patch element  3405   a ,  3406   a , respectively and thus may be used by the power divider  2008  of  FIG. 20  to separately provide signals to the first patch element  3405   a  and/or the second patch element  3406   a.    
     Still referring to  FIG. 34 , a power divider may be associated with the first dual patch antenna  3400   a . The power divider is not illustrated in  FIG. 34  for simplicity. The power divider may be internal or external to the first dual patch antenna  3400   a  but is electrically connected and/or coupled to the first stripline  3402   a  and/or the second stripline  3420   a . The power divider may be configured to control a power of the signal that is applied to the first patch element  3405   a  and/or the second patch element  3406   a . The first patch element  3405   a  and/or the second patch element  3406   a  may be configured such that a first polarization of the signal at the first patch element  3405   a  is orthogonal to a second polarization of the signal at the second patch element  3406   a.    
     Still referring to  FIG. 34 , the first dual patch antenna  3400   a  may be included in a Printed Circuit Board (PCB). In some embodiments, the first dual patch antenna  3400   a  may include a PCB ground plane  3416  in a seventh conductive layer  3415 . The seventh conductive layer  3415  may be separated from the second conductive layer  3414  by a third dielectric layer  3417 . The seventh conductive layer  3415  may be separated from the third conductive layer  3419  by a fifth dielectric layer  3418 . 
     The above discussed antenna structures for millimeter band radio frequency communication with dual radiating element antenna arrays may improve antenna performance by producing high gain signals that cover the three-dimensional space around a mobile device with uniform radiation patterns. In some embodiments, further performance improvements may be obtained by adding a plurality of power dividers to control various elements in the array of dual radiating element antennas based on signal conditions. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes,” “including,”, “having,” and/or variants thereof, when used herein, specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. 
     It will be understood that when an element is referred to as being “coupled,” “connected,” or “responsive” to another element, it can be directly coupled, connected, or responsive to the other element, or intervening elements may also be present. In contrast, when an element is referred to as being “directly coupled,” “directly connected,” or “directly responsive” to another element, there are no intervening elements present. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     Spatially relative terms, such as “above,” “below,” “upper,” “lower,” “top,” “bottom,” and the like, may be used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” other elements or features would then be oriented “above” the other elements or features. Thus, the term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. Well-known functions or constructions may not be described in detail for brevity and/or clarity. 
     It will be understood that, although the terms “first,” “second,” etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. Thus, a first element could be termed a second element without departing from the teachings of the present embodiments. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which these embodiments belong. It will be further understood that terms, such as those defined in commonly-used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly-formal sense unless expressly so defined herein. 
     Many different embodiments have been disclosed herein, in connection with the above description and the drawings. It will be understood that it would be unduly repetitious and obfuscating to literally describe and illustrate every combination and subcombination of these embodiments. Accordingly, the present specification, including the drawings, shall be construed to constitute a complete written description of all combinations and subcombinations of the embodiments described herein, and of the manner and process of making and using them, and shall support claims to any such combination or subcombination. 
     In the drawings and specification, there have been disclosed various embodiments and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation.