Patent Publication Number: US-11050160-B2

Title: Planar-shaped antenna devices, antenna arrays, and fabrication

Description:
RELATED APPLICATIONS 
     This application is related to and claims the benefit of earlier filed U.S. Provisional Patent Application Ser. No. 62/486,133 entitled “PLANAR-SHAPED ANTENNA DEVICE AND ANTENNA ARRAYS,” filed on Apr. 17, 2017, the entire teachings of which are incorporated herein by this reference. 
    
    
     GOVERNMENT RIGHTS 
     This invention was made with Government support under Award No. N00014-17-1-2008 awarded by the Office of Naval Research. The government may have certain rights in the invention. 
    
    
     BACKGROUND 
     Conventional antenna devices have been used to convey RF energy to a target recipient. For example, one type of antenna device is a so-called patch antenna. 
     A patch antenna (also known as a rectangular microstrip antenna) is a type of radio antenna with a low profile, which can be mounted on a flat surface. It consists of a flat rectangular sheet or “patch” of metal, mounted over a larger sheet of metal called a ground plane. They are the original type of microstrip antenna in which two metal sheets together form a resonant piece of microstrip transmission line with a length of approximately one-half wavelength of the radio waves. The radiation mechanism in a microstrip line arises from discontinuities at each truncated edge of the microstrip transmission line. The radiation at the edges causes the antenna to act slightly larger electrically than its physical dimensions, so in order for the antenna to be resonant, a length of microstrip transmission line slightly shorter than one-half a wavelength at the frequency is used. 
     BRIEF DESCRIPTION OF EMBODIMENTS 
     Conventional patch antennas suffer from deficiencies. For example, a conventional patch antenna may be substantially planar and suitable for use on a respective printed circuit board. However, conventional patch antennas operate in a resonant mode, rendering the conventional patch antenna unable to operate in a high gain mode. In other words, although planar in nature, a conventional patch antenna does not provide high signal gain, limiting its usefulness in many wireless applications. 
     This disclosure further includes the observation that conventional antennas such as reflector antennas, horn antennas, etc., may provide high gain. However, such antennas are heavy, bulky, and large in profile, which results in high manufacturing costs and difficulty for fabrication and integration. 
     In contrast to conventional antenna devices, embodiments herein include a novel planar, high-gain antenna. The substantially planar antenna devices described herein are light-weight, low-cost, and easily integrated/fabricated on a respective circuit board or other suitable substrate. 
     More specifically, in one example embodiment, the antenna device as described herein includes a first metal layer and a second metal layer. The second metal layer is spaced apart from the first metal layer. The first metal layer includes an opening (such as a slot or other shape) through which to transmit RF (Radio Frequency) energy to the second metal layer. The second metal layer is operable to reflect the RF energy received through the opening back to a surface of the first metal layer. The first metal layer is operable to reflect the RF energy (received from the reflection off the second metal layer) in a direction past the second metal layer through a communication medium such as air to a target recipient. 
     A combination of the first metal layer and the second metal layer form a highly directional antenna in which a main lobe of the directional antenna radiates in a direction approximately orthogonal to a planar surface of the first metal layer and the second metal layer. 
     In accordance with further embodiments, a planar surface area of the first metal layer is disposed orthogonal with respect to a direction of the RF energy passing through the opening to the second metal layer. The surface area of the first metal layer is sufficiently larger than a surface area of the second metal layer to reflect the RF energy past the second metal layer into the communication medium. In other words, in one embodiment, the first metal layer is operable to reflect RF energy such that at least a portion of it (the reflected energy) passes outside a periphery of the second metal layer (as opposed to being blocked or reflected again by the second metal layer which would cause resonance). 
     In yet further embodiments, a surface area of the first metal layer is substantially greater than a surface area of the second metal layer; the first metal layer and the second metal layer are planar and disposed in parallel with respect to each other. For example, in accordance with more specific embodiments, the surface area of the first metal layer is at least 3 times greater than a surface area of the second metal layer. This helps to ensure that the antenna device operates in a reflective mode as opposed to a resonant mode. In other words, when the surface area of the first metal layer is sufficiently larger (at least twice as large) than a surface area of the second metal layer, the combination of the first metal layer and the second metal layer operate in a non-resonant operational mode to convey RF energy in a desired direction from the antenna device. 
     As previously discussed, the opening in the first metal layer can be a slot or other suitable shaped opening. The second metal layer is disposed directly above the slot (such as on a different substrate) to reflect energy received from the slot back to a facing of the first metal layer. In accordance with further embodiments, the slot is wider than the width of the second metal surface. 
     In accordance with further embodiments, a lengthwise axis of the slot is disposed perpendicular to a transmission line (such as a microstrip line) on which RF energy is conveyed from a driver circuit to the opening in the first metal layer. 
     The thickness of a spacer separating the first metal layer and the second metal layer can be any suitable value such that the corresponding antenna device including a combination of the first metal layer, spacer (such as air), and the second metal layer is substantially planar. In one embodiment, the space separating the first metal layer and the second metal layer is less than 25% of the wavelength of the RF energy transmitted through the opening. 
     The antenna device as described herein can be disposed on any suitable substrate. In one embodiment, the first metal layer is disposed on a printed circuit board. The second metal layer is fabricated above the first metal layer. 
     Further, note that the antenna device as described herein can be used individually and as a source from which to transmit or receive RF energy. 
     Additionally, in accordance with further embodiments, multiple planar antenna devices as described herein can used as a feeding antenna such as for transmitarray and reflectarray antennas. 
     Horn antennas or open-ended waveguides are typically used as feeding antennas for transmitarray and reflectarray antennas. In such an instance, the distance from the feeding antenna to the array is very large (e.g. several wavelengths). As a result, conventional transmitarray and reflectarray are typically bulky and heavy. Using an array of antenna devices as a feeding antenna (instead of horn antennas or open-ended waveguides), the distance from the feeding antenna to the array can be reduced by a factor of 10 or more (e.g. because the antenna devices described herein is sub-wavelength in size). 
     Further embodiments herein include a fabricator (such as manufacturing facility, assemblers, technicians, machines, computers, etc.) operable to fabricate a surface area of the first metal layer to be orthogonal to a direction in which to receive the RF energy through the opening (slot), the surface area of the first metal layer is sufficiently larger than a surface area of the second metal layer to reflect the RF energy past the second metal layer to a target device in a communication medium. In one embodiment, as previously discussed, the fabricator fabricates a surface area of the first metal layer to be at least 3 times greater than a surface area of the second metal layer. 
     In accordance with further embodiments, the fabricator is operable to fabricate the first metal layer and the second metal layer fabricated to be planar and disposed in parallel with respect to each other. 
     In yet further embodiments, the fabricator is operable to fabricate a surface area of the first metal layer to be sufficiently larger than a surface area of the second metal layer such that the combination of the first metal layer and the second metal layer operate in a non-resonant operational mode. The fabricator disposes the second metal layer directly above the slot. 
     In yet further embodiments, the fabricator is operable to dispose a lengthwise axis of the slot to be disposed perpendicular to a transmission line on which the RF energy is conveyed from a driver circuit to the opening (slot). 
     Further embodiments herein include fabricating a combination of the first metal layer and the second metal layer to form a directional antenna in which a main lobe of the directional antenna extends in an orthogonal direction from a planar surface of the first metal layer. 
     In still further embodiments, the fabricator fabricates the first metal layer to convey at least a portion of the RF energy outside a periphery of the second metal layer to a communication medium. 
     In accordance with further embodiments, the fabricator: couples the first metal layer to a ground reference voltage; receives a substrate including a first facing and a second facing; disposes the first metal layer on the first facing of the substrate; and disposes a feed line (feed network) on the second facing, the feed line operable to convey a signal to the opening to transmit the RF energy. 
     In still further embodiments, the opening is a first opening in the first metal layer; the RF energy is first RF energy. The fabricator method further performs operations of: fabricating a third metal layer to be spaced apart from the first metal layer; and disposing a second opening in the first metal layer, the second opening operable to transmit second RF (Radio Frequency) energy to the third metal layer, the third metal layer operable to reflect the second RF energy received through the second opening back to the first metal layer, the first metal layer operable to reflect the second RF energy from the third metal layer in a direction past the third metal layer to the communication medium. 
     In yet further embodiments, in a so-called wide band configuration, the third metal layer resides in a same plane as the second metal layer; and the first metal layer is planar, both the second metal layer and the third metal layer parallel to the first metal layer. The fabricator: disposes a substrate between the first metal layer and a combination of the second metal layer and the third metal layer; fabricates a fifth metal layer on the substrate to be disposed between the first metal layer and the third metal layer; and fabricates a sixth metal layer on the substrate to be disposed between the first metal layer and the fourth metal layer. 
     In still further embodiments, a combination of the first opening, the first metal layer, and the second metal layer are operable to output the first RF energy at a first carrier frequency; and a combination of the second opening, the first metal layer, and the third metal layer are operable to support output the first RF energy at a second carrier frequency. 
     In one embodiment, the fabricator: fabricates the second metal layer as a first patch antenna element operable to support emission of the first RF energy; and fabricates the third metal layer as a second patch antenna element of multiple patch antenna elements that are collectively operable to support emission of the second RF energy. As previously discussed, the fabricator can be configured to fabricate the first patch antenna element to be substantially larger in surface area size than the second patch antenna element. 
     These and other more specific embodiments are disclosed in more detail below. 
     Note that any of the resources as discussed herein can include one or more computerized devices, mobile playback devices, servers, base stations, wireless playback equipment, playback management systems, workstations, handheld or laptop computers, or the like to carry out and/or support any or all of the method operations disclosed herein. In other words, one or more computerized devices or processors can be programmed and/or configured to operate as explained herein to carry out the different embodiments as described herein. 
     Yet other embodiments herein include software programs to perform the steps and operations summarized above and disclosed in detail below. One such embodiment comprises a computer program product including a non-transitory computer-readable storage medium (i.e., any computer readable hardware storage medium or hardware storage media disparately or co-located) on which software instructions are encoded for subsequent execution. The instructions, when executed in a computerized device (hardware) having a processor, program and/or cause the processor (hardware) to perform the operations disclosed herein. Such arrangements are typically provided as software, code, instructions, and/or other data (e.g., data structures) arranged or encoded on a non-transitory computer readable storage media such as an optical medium (e.g., CD-ROM), floppy disk, hard disk, memory stick, memory device, etc., or other a medium such as firmware in one or more ROM, RAM, PROM, etc., and/or as an Application Specific Integrated Circuit (ASIC), etc. The software or firmware or other such configurations can be installed onto a computerized device to cause the computerized device to perform the techniques explained herein. 
     Accordingly, embodiments herein are directed to a method, system, computer program product, etc., that supports operations as discussed herein. 
     One embodiment includes a computer readable storage media and/or a system having instructions stored thereon to facilitate fabrication of an antenna device as discussed herein. For example, in one embodiment, the instructions, when executed by computer processor hardware, cause the computer processor hardware (such as one or more processor devices) to: fabricate a first metal layer; fabricate a second metal layer; space the first metal layer from the second metal layer; produce the first metal layer to include an opening through which to transmit RF (Radio Frequency) energy to the second metal layer, the second metal layer operable to reflect the RF energy received through the opening back to the first metal layer, the first metal layer operable to reflect the RF energy off the second metal layer in a direction past the second metal layer to a communication medium. 
     The ordering of the steps above has been added for clarity sake. Note that any of the processing steps as discussed herein can be performed in any suitable order. 
     Other embodiments of the present disclosure include software programs and/or respective hardware to perform any of the method embodiment steps and operations summarized above and disclosed in detail below. 
     It is to be understood that the system, method, apparatus, instructions on computer readable storage media, etc., as discussed herein also can be embodied strictly as a software program, firmware, as a hybrid of software, hardware and/or firmware, or as hardware alone such as within a processor (hardware or software), or within an operating system or a within a software application. 
     As discussed herein, techniques herein are well suited for use in the field of content playback and specifically identification of desirable and undesirable portions of content. Moreover, embodiments herein impact all applications involving transmitting/receiving electromagnetic signals with improved performance (e.g. higher data rate) and reduced cost, size and weight. A few examples are listed below: 5G wireless communication systems, satellite and space communication systems, automobile radar systems, wireless network on chips (e.g. chip to chip communication), phased array systems (operating at the frequency bands of RF/microwave, millimeter-wave, THz, infrared, and visible). However, it should be noted that embodiments herein are not limited to use in such applications and that the techniques discussed herein are well suited for other applications as well. 
     Additionally, note that although each of the different features, techniques, configurations, etc., herein may be discussed in different places of this disclosure, it is intended, where suitable, that each of the concepts can optionally be executed independently of each other or in combination with each other. Accordingly, the one or more present inventions as described herein can be embodied and viewed in many different ways. 
     Also, note that this preliminary discussion of embodiments herein purposefully does not specify every embodiment and/or incrementally novel aspect of the present disclosure or claimed invention(s). Instead, this brief description only presents general embodiments and corresponding points of novelty over conventional techniques. For additional details and/or possible perspectives (permutations) of the invention(s), the reader is directed to the Detailed Description section and corresponding figures of the present disclosure as further discussed below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an example diagram illustrating a side view of a wireless antenna device according to embodiments herein. 
         FIG. 2  is an example diagram illustrating a top view of a wireless antenna device according to embodiments herein. 
         FIG. 3  is an example diagram illustrating a three-dimensional view of a wireless antenna device according to embodiments herein. 
         FIG. 4  is an example diagram illustrating operation of the wireless antenna device according to embodiments herein. 
         FIG. 5  is an example diagram illustrating a first example radiation pattern of RF energy emitted from a wireless antenna device according to embodiments herein. 
         FIG. 6  is an example diagram illustrating a second example radiation pattern of RF energy emitted from a wireless antenna device according to embodiments herein. 
         FIG. 7  is an example diagram illustrating a third example radiation pattern of RF energy emitted from a wireless antenna device according to embodiments herein. 
         FIG. 8A  is an example top view diagram illustrating a first antenna device in a wideband configuration system according to embodiments herein. 
         FIG. 8B  is an example side view diagram illustrating attributes of a first antenna device in the wideband configuration system according to embodiments herein. 
         FIG. 9A  is an example diagram illustrating return loss power distribution from the first antenna device across multiple frequencies according to embodiments herein. 
         FIG. 9B  is an example diagram illustrating gain of the first antenna device across multiple frequencies according to embodiments herein. 
         FIG. 10  is an example diagram illustrating an example radiation pattern of the first antenna device according to embodiments herein. 
         FIG. 11A  is an example top view diagram illustrating a second antenna device in the wideband configuration system (including multiple antenna elements) according to embodiments herein. 
         FIG. 11B  is an example side view diagram illustrating attributes of the second antenna system according to embodiments herein. 
         FIG. 12A  is an example diagram illustrating return loss from an antenna system (of  FIG. 11B ) across multiple frequencies according to embodiments herein. 
         FIG. 12B  is an example diagram illustrating gain of an antenna system (of  FIG. 11B ) across multiple frequencies according to embodiments herein. 
         FIG. 13  is an example diagram illustrating an example radiation pattern of one of the element in an antenna system (of  FIG. 11B ) according to embodiments herein. 
         FIG. 14A  is an example top view diagram illustrating a third antenna system (including multiple antenna elements) according to embodiments herein. 
         FIG. 14B  is an example side view diagram illustrating attributes of the third antenna system according to embodiments herein. 
         FIG. 15  is an example diagram illustrating attributes of the feeding network of the multi-band antenna system (third system,  FIG. 14B ) according to embodiments herein. 
         FIG. 16  is an example diagram illustrating a fabrication layer to implement the feeding network of the multi-band antenna system (third system,  FIG. 14B ) according to embodiments herein. 
         FIG. 17  is an example diagram illustrating an example radiation pattern of the multiple-band antenna system (third system,  FIG. 14A ) according to embodiments herein. 
         FIG. 18  is a diagram illustrating example computer architecture to execute operations according to embodiments herein. 
         FIG. 19  is an example diagram illustrating a method according to embodiments herein. 
     
    
    
     The foregoing and other objects, features, and advantages of the invention will be apparent from the following more particular description of preferred embodiments herein, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, with emphasis instead being placed upon illustrating the embodiments, principles, concepts, etc. 
     DETAILED DESCRIPTION 
     Now, more specifically, with reference to the figures,  FIG. 1  is an example diagram illustrating a side view of an antenna device according to embodiments herein. 
     In this example embodiment, antenna device  100  includes a first metal layer  120 - 1  disposed on surface  121 - 1  (reflector) of substrate  160 . The antenna device  100  also includes a second metal layer  120 - 2  disposed on surface  121 - 2  (patch antenna element) disposed on substrate  170 . 
     As shown, the metal layer  120 - 2  is spaced apart (such as using a dielectric material or air) from metal layer  120 - 1 ; a surface  121 - 2  of metal layer  120 - 2  faces the surface  121 - 1  of the metal layer  120 - 1 . 
     Each of the metal layers  120  can be fabricated from any suitable combination of one or more metals such as copper, aluminum, tin, etc. 
     Each of the substrate  160  and  170  can be fabricated from any suitable dielectric material such as ceramic, epoxy, etc. 
     In general, dielectric material is insulating material or a very poor conductor of electric current. When dielectric material is placed in an electric field, practically no current flows in them because, unlike metals, they have no loosely bound, or free, electrons that may drift through the material. 
     Further in this example embodiment, as further described herein, a surface area of the metal layer  120 - 1  is sufficiently greater in size than a surface area of the metal layer  120 - 2  to emit wireless energy in a direction as indicated by the Z-axis (or, more specifically, direction  497 ). 
     As previously discussed, in contrast to conventional antenna devices, antenna device  100  is a novel multi-layer, substantially planar, non-resonant (or reflective), type of high-gain antenna. In contrast to conventional antenna devices, such a planar antenna device (apparatus, system, etc.) is light-weight, low-cost, and easily integrated/fabricated on a respective circuit board or other suitable substrate. 
     As further shown, the antenna device  100  can be driven using driver  110 . The driver  110  can be disposed on the substrate  160  or other suitable substrate. 
     Feed line  150  (such as a microstrip line, waveguide, or feeding network, etc.) conveys RF energy from the driver  110  to the slot  141  (opening) of the antenna device  100 . As further discussed herein, the antenna device  100  outputs wireless RF energy substantially in a direction  497  as indicated by the z-axis. 
     In accordance with further embodiments, the substrate  160  is a printed circuit board substrate (non electrically conductive and/or insulation-type material such as one or more layers of epoxy and traces) on which the antenna device  100  is fabricated. 
     In one embodiment, the metal layer  120 - 1  is connected to a ground voltage reference. 
     As further shown in  FIG. 1 , metal layer  120 - 2  is disposed directly over the slot  141  (such as an opening, gap, channel, port, window, etc.). In one embodiment, the slot  141  is an opening in which to launch RF energy in a direction toward the metal layer  120 - 2 . 
     In accordance with further embodiments, as previously discussed, the metal layer  120 - 2  is spaced apart with respect to the first metal layer  120 - 1  via the dielectric layer  122  (insulator such as air or other non-conducting or nearly non-conducting material). 
     As further described herein, a combination of the first metal layer  120 - 1  and the second metal layer  120 - 2  combine to form directional antenna device  100  in which the beam of the directional antenna  100  radiates substantially in a direction orthogonal to planar surface  121 - 1  (generally along z-axis and direction  497 ). Thus, a planar surface  121 - 1  area of the first metal layer  120 - 1  is disposed orthogonal with respect to a direction  497  of RF energy passing through the slot  141  to the second metal layer  120 - 2 . 
       FIG. 2  is an example diagram illustrating a top view of a wireless antenna device and stacking of a second metal layer with respect to a first metal layer according to embodiments herein. 
     As shown, the surface area of the first metal layer  120 - 1  (as viewed along z-axis) is sufficiently and/or substantially larger than a surface area of the second metal layer  120 - 2 . 
     In general, slot  141  emits wireless RF energy to the metal layer  120 - 2 . Metal layer  120 - 2  reflects the RF energy to the metal layer  120 - 1 . The metal layer  120 - 2  reflects the energy from metal layer  120 - 2  in a direction substantially along the z-axis into a respective communication medium such as air. 
     Each of the metal layer  120 - 1  and metal layer  120 - 2  can be any suitable sized surface area. In one embodiment, as shown, the surface area of the metal layer  120 - 1  is at least 3 times larger than a surface area of the metal layer  120 - 2 . 
     As previously discussed, the slot  141  can be any suitable shaped opening. In one embodiment, the slot  141  (opening) is rectangular. 
     As further shown, in one embodiment, the second metal layer  120 - 2  is disposed directly above and centered with respect to the slot  141 . This enables surface  121 - 2  of the metal layer  120 - 2  to reflect RF energy received from the slot  141  (i.e., opening) back to a facing (surface  121 - 1 ) of the first metal layer  120 - 1 . Alternatively, note that the second metal layer  120 - 2  can be offset with respect to the slot  141 . 
     In accordance with further embodiments, a lengthwise axis (such as along the x-axis) of the slot  141  is disposed perpendicular to a lengthwise axis (y-axis) of the feedline  150  (such as a microstrip line or other suitable transmission line) on which RF energy is conveyed from the driver  110  to the slot  141  of the first metal layer  120 - 1 . 
     As further shown, by way of non-limiting example embodiment, the length of slot  141  is greater in size (along the x-axis) than the width of the second metal layer  120 - 2  along the x-axis. As further shown, in one embodiment, the width of slot  141  along the y-axis is substantially smaller in size than the width of the second metal layer  120 - 2  along the x-axis. 
     The length and width of the slot  141  can be any suitable values and vary depending on the embodiment. 
       FIG. 3  is an example diagram illustrating a three-dimensional view of the antenna device according to embodiments herein. 
     As shown in  FIG. 3 , the second metal layer  120 - 2  is spaced apart with respect to the first metal layer  120 - 1  by the thickness, T. 
     Assume that the wavelength value, WL (or Lambda), represents a wavelength of a corresponding RF signal conveyed from the driver  110  over the feedline  150  to the slot  141 . 
     In accordance with certain embodiments, the thickness or spacing, T, can be set to any suitable dimension. In one embodiment, the thickness or spacing, T, is set to a value such as between 0.001 and 0.5*WL or greater; the length L 1  and L 2  can be any suitable dimension such as greater than 0.125*WL; the length L 3  and L 4  can be any suitable dimension such as greater than 0.1*WL. 
     By way of non-limiting example embodiment, assume in this example embodiment that the frequency of the corresponding RF signal is 5 GHz. In such an instance, the wavelength is approximately 60 mm (millimeters). Each of the lengths L 1  and L 2  are each 50 mm (0.83*WL). Each of the lengths L 3  and L 4  are each 21.8 mm (0.36*WL). The thickness T is 7.4 mm (0.12*WL). 
     However, as previously discussed, these values may vary depending on the embodiment. 
     Note further that the thickness, T, of the spacer (or spacing) separating the first metal layer  120 - 1  and the second metal layer  120 - 2  can be any suitable value such that a shape of the corresponding antenna device  100  including a combination of the first metal layer  120 - 1  and the second metal layer  120 - 2  is substantially planar. In other words, the thickness is relatively small compared to L 1  and/or L 2 . 
     In one embodiment, respective spacer material, air, vacuum, etc., separating the first metal layer  120 - 1  and the second metal layer  120 - 2  is less than 25% of the wavelength of the RF energy transmitted through the slot  141 . 
     When the surface area (L 1 ×L 2 ) of the first metal layer  120 - 1  is sufficiently larger than a surface area (L 3 ×L 4 ) of the second metal layer  120 - 2 , the combination of the first metal layer  120 - 1  and the second metal layer  120 - 2  operate in a non-resonant or reflective operational mode to convey a respective RF energy in a desired direction from the antenna device  100 . 
     As previously discussed, in one embodiment, the surface area of the first metal layer  120 - 1  in the X-Y plane is at least 3 times greater than a surface area of the second metal layer  120 - 2  in the X-Y plane. This ensures that the antenna device  100  operates in a reflective mode as opposed to a resonant mode. 
       FIG. 4  is an example diagram illustrating reflective operation of the wireless antenna device according to embodiments herein. 
     In this example embodiment, the driver  110  transmits the signal  405  through the feedline  150  to the slot  141 . 
     The energy associated with the signal  405  wirelessly passes through the slot  141  (opening) of the first metal layer  120 - 1  as wireless RF energy  415 . The RF energy  415  strikes the surface  121 - 2  of the second metal layer  120 - 2 . 
     The second metal layer  120 - 2  reflects the received RF energy  410  as RF energy  420  back to the surface  121 - 1  of the metal layer  120 - 1 . As further shown, the surface  121 - 1  of the metal layer  120 - 1  reflects the received RF energy  420  as reflected RF energy  430  (in the Z-axis, or direction  497 ) to a communication medium such as air. 
     Note that the antenna device  100  can include additional metal layer  493  (spaced from substrate  160 ) to reduce an amount of RF energy transmitted from antenna device  100  in direction  498 . 
     In one embodiment, because the surface area  121 - 2  of the second metal layer  120 - 2  is substantially smaller than the surface area of surface  121 - 1  of metal layer  120 - 1 , the surface  121 - 1  of the first metal layer  120 - 1  is operable to reflect the RF energy  420  such that corresponding RF energy  430  passes outside a periphery (peripheral edges) of the second metal layer  120 - 2  (as opposed to being blocked or reflected again by the second metal layer  120 - 2 ) to a respective communication medium such as air to a recipient. 
     Further, note that the antenna device  100  as described herein can be used individually, and as a source from which to transmit or receive RF energy. 
     Additionally, in accordance with further embodiments, multiple planar antenna devices (similar to antenna device  100 ) as described herein can be can be formed as an array for use as a feeding antenna for transmitarray and reflectarray antennas. 
     Note that conventional horn antennas or open-ended waveguides are typically used as feeding antennas for transmit array and reflect array antennas. In such a conventional instance, the distance from the feeding antenna to the array is very large (e.g. several wavelengths). As a result, conventional transmit array and reflect array are typically bulky and heavy. 
     In contrast to conventional arrays, using an array of antenna device  100  (apparatus, system, etc.) as a feeding antenna (instead of horn antennas or open-ended waveguides), the distance from the feeding antenna to the array can be reduced by a factor of 10 or more (e.g., the distance between the feeding and the array is sub-wavelength). 
       FIG. 5  is an example diagram illustrating a first example radiation pattern from the wireless antenna device according to embodiments herein. 
     Assume that the antenna device  100 - 1  (a first example instance of antenna device  100 ) has the following dimensions:
 
 T= 0.12*WL (7.4 mm),
 
 L 1= L 2=0.83*WL (50 mm), and
 
 L 3= L 4=0.36*WL (21.8 mm).
 
     Assume that the frequency of the signal  405  is 5 GHz. 
     In such an instance, the antenna device  100 - 1  produces the radiation pattern  510  and pattern  520  in which directivity is 9.1 dB, maximum aperture directivity is 9.4 dB, and aperture efficiency is 93.3% on the z-axis. 
       FIG. 6  is an example diagram illustrating a second example radiation pattern from a wireless antenna device according to embodiments herein. 
     Assume that the antenna device  100 - 2  (second example instance the antenna device  100 ) has the following dimensions:
 
 T= 0.12*WL (7.4 mm),
 
 L 1= L 2=1.67*WL (100.2 mm), and
 
 L 3= L 4=0.36*WL (21.8 mm).
 
     Assume that the frequency of the signal  405  is 5 GHz. 
     In such an instance, the antenna device  100 - 2  produces the radiation pattern  610  and pattern  620  in which directivity is 15 dB, maximum aperture gain is 15.4 dB, and aperture efficiency is 91.2% on the z-axis. 
       FIG. 7  is an example diagram illustrating a third example radiation pattern from a wireless antenna device according to embodiments herein. 
     Assume that the antenna device  100 - 3  has the following dimensions:
 
 T= 0.12*WL (7.4 mm),
 
 L 1=6.67*WL (400.2 mm),
 
 L 2=1.67*WL (100.2 mm), and
 
 L 3= L 4=0.36*WL (21.8 mm).
 
     Assume that the frequency of the signal  410  is 5 GHz. 
     In such an instance, the antenna device  100 - 3  produces the radiation pattern  710  and pattern  720  in which directivity is 21.6 dB, and aperture efficiency is &gt;99% on the z-axis. 
     As discussed herein, the proposed antenna device can be constructed by two metal layers separated by a small distance (subwavelength such as a half the wavelength of the driver signal). One metal layer functions as the reflector and one metal layer functions as the radiating element and sub-reflector. Through the combined effect of these two layers, embodiments herein achieve a radiation aperture efficiency of 90% or even higher. Compared to conventional high-gain antennas such as horn and reflector antennas, the proposed antenna device  100  is substantially planar with sub-wavelength overall profile, which makes it easy for fabrication and integration as well as low-cost and light-weight. Other unique features include: 
     1. The antenna device  100  can be implemented on all available platforms for planar high frequency circuits including printed circuit board (PCB), integrated circuits (CMOS, Bi-CMOS, GaAs, GaN microwave monolithic integrated circuit (MMIC)), low-temperature co-fired ceramic (LTCC), liquid-crystal polymer (LCP). 
     2. The antenna device  100  can be applied for systems operating at the radio-frequency (RF)/microwave, terahertz (THz), infrared (IR), visible, and even higher. 
     3. The antenna device  100  can support electromagnetic signals with arbitrary polarizations (e.g. linear, circular, elliptical). 
     4. The antenna device  100  can be used as the feeding antenna for transmitarray and reflectarray antennas. 
       FIG. 8A  is an example top view diagram illustrating a type of antenna system according to embodiments herein. 
     As shown in this example embodiment, antenna device  800  includes metal layer  820 - 2  (such as a patch antenna element) disposed over metal layer  820 - 1 . Additional details of the antenna device  800  are discussed below in  FIG. 8B . 
       FIG. 8B  is an example side view diagram illustrating an antenna system according to embodiments herein. 
     Note that the antenna device  800  in  FIG. 8B  operates in a similar manner as the antenna device  100  as previously discussed in  FIG. 1 . 
     In one embodiment, the antenna device  800  operates in a first predetermined frequency band such as between 18 and 30 GHz. 
     More specifically, as shown in  FIG. 8B , antenna device  800  includes a stacking and spacing of substrate  860 , substrate  865  (optional), and substrate  870 . In one embodiment, the substrates are spaced apart via air layers, although any suitable material can be used to separate substrates. 
     Further in this example embodiment, metal layer  820 - 1  is disposed on substrate  860 . Metal layer  820 - 2  (patch antenna element) is disposed on substrate  870 . 
     Metal layer  820 - 1  includes opening  841  in which to emit an RF signal  805  conveyed from resource  810 . More specifically, during operation, the resource  810  (such as a driver) produces signal  805  (such as a RF signal) conveyed over feed line  850  to the opening  841 . The location  808  of the feed line  805  acts as a radiation source from which RF energy  811  (from signal  805 ) is wirelessly transmitted through substrate  860  (such as a dielectric material) and opening  841  of metal layer  820 - 1  (disposed on substrate  860 ). 
     Metal layer  820 - 2  receives RF energy  811  and reflects the received RF energy  811  as RF energy  821  back through substrate  865  (when present) to metal layer  820 - 1  as shown. Metal layer  820 - 1  reflects the RF energy  821  as RF energy  831  approximately in direction  895  from antenna device  800  to a remote communication device. 
     As previously discussed, note again that the antenna device  800  can include a respective reflector  893  (such as metal layer) to limit an amount of RF energy that is transmitted in direction  896  such as to a remote resource such as communication device  817 . 
       FIG. 9A  is an example diagram illustrating return loss from an antenna device across multiple frequencies according to embodiments herein. 
     Graph  910  illustrates the return loss of the antenna device  800  (i.e. returned power to the source of a respective input signal for different carrier frequencies transmitted from antenna device  800 ). In general, as indicated by graph  910 , the antenna device  800  is suitable to transmit RF energy at carrier frequencies between 18 and 30 GHz. 
       FIG. 9B  is an example diagram illustrating gain of an antenna device across multiple frequencies according to embodiments herein. 
     In this example embodiment, graph  920  illustrates that the gain provided by antenna device  800  is above a threshold value for different signals from antenna device  800  transmitted at carrier frequencies 18-30 GHz. Thus, as indicated by graph  920 , the antenna device  800  is suitable to transmit RF energy at carrier frequencies between 18 and 30 GHz. 
       FIG. 10  is an example diagram illustrating an example radiation pattern of an antenna device according to embodiments herein. 
     Graph  1000  indicates gain associated with antenna device  800  (such as without reflector  893 ) at different angular orientations with respect to the antenna device  800 . As shown, antenna device  800  transmits RF signals mainly in direction  895 . As previously discussed, antenna device  800  can include reflector  893  to reduce an amount of wireless RF transmitted in direction  896 . 
       FIG. 11A  is an example top view diagram illustrating a second device according to embodiments herein. 
     As shown, antenna device  1100  includes multiple metal layers including patch antenna elements associated with antenna element  1181 ,  1182 ,  1183 , and  1184  disposed over metal layer  1120 - 1 . Thus, antenna device  1100  can be configured to include multiple patch antenna elements to transmit and receive RF energy. 
       FIG. 11B  is an example side view diagram illustrating an antenna system according to embodiments herein. 
     In this example embodiment, each of the antenna elements  1181 ,  1182 , etc., in the antenna device  1100  in  FIG. 11B  operates in a similar manner as the antenna device  100  as previously discussed in  FIG. 1 . However, a combination of or individual antenna elements  1181 ,  1182 , etc., of the antenna device  1100  operate(s) in a second predetermined frequency band such as between 30 and 50 GHz. 
     More specifically, as shown in  FIG. 11B , antenna device  1100  includes a stacking of substrate  1160 , substrate  1165 , and substrate  1170 . In one embodiment, the substrates are spaced apart via air layers or dielectric material. 
     Metal layer  1120 - 1  of antenna device  1100  is disposed on substrate  1160 . In this example embodiment, metal layer  1120 - 1  includes multiple openings  1141 - 1 ,  1141 - 2 , etc., associated with each of the antenna elements  1181 ,  1182 , etc. 
     As further discussed below, opening  1141 - 1  in metal layer  1120 - 1  provides a location (with respect to feed line  1150 ) from which to transmit/receive RF energy associated with antenna element  1181  (such as a combination of patch antenna element  1121 - 1 , coupling structure  1131 - 1 , and patch antenna element  1122 - 1 ); opening  1141 - 2  provides a location (with respect to feed line  1150 ) from which to transmit/receive RF energy associated with antenna element  1182  (such as a combination of patch antenna element  1121 - 2 , coupling structure  1131 - 2 , and patch antenna element  1122 - 2 ); and so on. 
     During operation, the source  1110  (such as a driver) produces signal  1105  (such as an RF signal) conveyed over feed line  1150  to the openings  1141 - 1 ,  1141 - 2 , etc. 
     The location  1108 - 1  of the feed line  1105  acts as a radiation source from which RF energy  1111 - 1  (from signal  1105 ) is transmitted through opening  1141 - 1  to antenna element  1181 . A combination of patch antenna element  1121 - 1 , coupling structure  1131 - 1 , and patch antenna element  1122 - 1  of antenna element  1181  reflects the received RF energy  1111 - 1  as RF energy  1111 - 2  to the metal layer  1120 - 1 . Metal layer  1120 - 1  reflects the received RF energy  1111 - 2  and reflects it approximately in direction  1195  as RF energy  1111 - 3  from antenna device  1100 . 
     Additionally, the location  1108 - 2  of the feed line  1105  acts as a radiation source from which RF energy  1112 - 1  (generated from signal  1105 ) through opening  1141 - 2  is transmitted through to antenna element  1182 . A combination of patch antenna element  1121 - 2 , coupling structure  1131 - 2 , and patch antenna element  1122 - 2  associated with antenna element  1182  reflects the received RF energy  1112 - 1  as RF energy  1112 - 2  to the metal layer  1120 - 1 . Metal layer  1120 - 1  reflects the received RF energy  1112 - 2  and reflects it approximately in direction  1195  as RF energy  1112 - 3  from antenna device  1100 . 
     Each of the four antenna elements  1181 ,  1182 ,  1183 , and  1184  in substrate  1165  and  1170  operate in a similar manner to produce an overall wireless signal transmitted from antenna device  1100 . 
     In a similar manner as previously discussed, the antenna device  1100  can include a respective reflector  1193  (such as metal layer) to limit or reduce an amount of RF energy that is transmitted in direction  1196  from antenna device  1100 . 
       FIG. 12A  is an example diagram illustrating power distribution from an antenna device across multiple frequencies according to embodiments herein. 
     More specifically, graph  1210  of  FIG. 12A  illustrates transmission power of a respective input signal for different carrier frequencies transmitted from antenna elements of antenna device  1100 . In general, as shown, the antenna device  1100  is suitable to transmit RF energy at carrier frequencies in a band between 30 and 50 GHz. 
       FIG. 12B  is an example diagram illustrating gain of an antenna device across multiple frequencies according to embodiments herein. 
     Graph  1220  illustrates that the gain provided by antenna device  1100  is above a threshold value for different carrier frequencies 30-50 GHz transmitted from antenna device  1100 . 
       FIG. 13  is an example diagram illustrating an example radiation pattern of an antenna device according to embodiments herein. 
     Graph  1300  indicates gain associated with antenna device  1100  at different angular orientations with respect to the antenna device  1100 . As shown, antenna device  1100  transmits RF signals mainly in direction  1195 . 
       FIG. 14A  is an example top view diagram illustrating attributes of a multi-band antenna system according to embodiments herein. 
     In this example embodiment, the antenna device  1400  includes a combination of a antenna element (such as metal layer  820 - 2 ) associated with antenna device  800  (of  FIG. 8B ) and antenna elements  1181 ,  1182 ,  1183 , and  1184  associated with antenna device  1100  (of  FIG. 11 ) to operate in multiple different bands. 
     For example, the metal layer  820 - 2  (such as a patch antenna element) supports wireless emissions of data in a first carrier frequency band (such as between 18-30 GHz); in a manner as previously discussed, the combination of antenna elements  1181 ,  1182 ,  1183 , and  1184  support wireless emissions of data in a second carrier frequency band (such as between 30-50 GHz). 
       FIG. 14B  is an example side view diagram illustrating attributes of a multi-band antenna system according to embodiments herein. 
     As shown, the antenna device  1400  includes a combination of antenna device  800  and antenna device  1100 . In this example embodiment, the metal layer  820 - 2  (such as a patch antenna element) associated with antenna element  1483  supports wireless emissions of data in a first carrier frequency band (such as between 18-30 GHz); the combination of antenna elements  1181 ,  1182 , etc., support wireless emissions of data in a second carrier frequency band (such as between 30-50 GHz). 
     Accordingly, antenna device  1400  operates in a dual band or broadband mode. 
       FIG. 15  is an example diagram illustrating attributes of the multi-band antenna system according to embodiments herein. 
     In one embodiment, the feedline  1450  (or feed network associated with the antenna device  1400 ) disposed on bottom of substrate  1160  includes low pass filter  1530 , high pass filter  1510 - 1 , and high pass filter  1510 - 2 . 
     In this example embodiment, the source (such as a transmitter and/or receiver) inputs RF signal  1405  to feed line  1450 . 
     Via respective filtering applied to the RF signal  1405 , the low pass filter  1530  conveys a first band (such as between 18-30 GHz) of frequencies of signal  1405  through the opening  841  (in metal layer  1120 - 1 ) to the metal layer  820 - 2 . 
     Via respective filtering applied to the RF signal  1405 , the high pass filter  1510 - 1  conveys a second band of frequencies (such as between 30-50 GHz) of signal  1405  through the openings  1142 - 1  and  1142 - 3  in metal layer  1120 - 1  to the respective antenna element  1181  (combination of patch antenna element  1121 - 1 , coupling structure  1131 - 1 , and patch antenna element  1122 - 1 ) and antenna element  1183  of antenna device  1400 . 
     Via respective filtering applied to the RF signal  1405 , the high pass filter  1510 - 2  conveys a second band of frequencies (such as between 30-50 GHz) of signal  1405  through the openings  1142 - 2  and  1142 - 4  in the metal layer  1120 - 1  to the respective antenna elements  1182  (combination of patch antenna element  1121 - 2 , coupling structure  1131 - 2 , and patch antenna element  1122 - 2 ) and antenna element  1184 . 
       FIG. 16  is an example diagram illustrating a top view of a fabrication layer (or feeding network) to implement the multi-band antenna system according to embodiments herein. 
     In this example embodiment, the feed line  1450  (and corresponding feed network) disposed on bottom of substrate  1160  of antenna device  1400  provides connectivity of resource  1410  (such as transmitter and/or receiver) to respective openings  1141 - 1 ,  1141 - 2 ,  841 , etc., disposed in metal layer  1120 - 1 . In the example embodiment shown, feed line  1150  and corresponding feeding network (associated with antenna device  1400 ) is a metal layer disposed on the bottom surface of substrate  1160 . 
     The different shapes associated with the high pass filters  1510 - 1  and  1510 - 2  as well as low pass filter  1530  provide filtering of signal  1405  such that respective openings receive the appropriate input RF signal. In a manner as previously discussed, via transmission of the lower frequencies of the input signal  1405  through low pass filter  1530  to the opening  841 , the antenna element  1483  (such as patch antenna element  820 - 2 ) supports conveyance of wireless data in direction  1495  from antenna device  1400 . 
     Via transmission of the higher frequencies of the input signal  1405  through high pass filter  1510 - 1  to the openings  1442 - 1 ,  1442 - 3 , etc., the corresponding antenna elements  1481  and  1483  support conveyance of wireless data in direction  1495  from antenna device  1400 . 
     Via transmission of the higher frequencies of the input signal  1405  through high pass filter  1510 - 2  to the openings  1442 - 2  and  1442 - 4 , the corresponding antenna elements  1482  and  1484  support conveyance of wireless data in direction  1495  from antenna device  1400 . 
       FIG. 17  is an example diagram illustrating an example radiation pattern of the multiple-band antenna device according to embodiments herein. 
     As shown in graph  1700 , the metal layer  820 - 2  (patch antenna element) supports wireless emissions at 24 GHz (such as for a first predetermined band between 18-30 GHz). 
     The antenna element  1181  (combination of patch antenna element  1121 - 1 , coupling structure  1131 - 1 , and patch antenna element  1122 - 1 ), antenna element  1182  (combination of patch antenna element  1121 - 2 , coupling structure  1131 - 2 , and patch antenna element  1122 - 2 ), antenna element  1483 , and antenna element  1484  associated with antenna device  1400  support wireless emissions at 40 GHz (such as for a second predetermined band between 30-50 GHz). 
     The graph  1700  illustrates that both antenna systems (such as patch antenna element  820 - 1  and antenna elements  1181 ,  1182 ,  1183 , and  1184 ) provide high gain in the direction  1495  from antenna device  1400 . In a similar manner as previously discussed, the antenna device  1400  can include a reflector  1493  to reduce RF energy transmitted in direction  1496 . 
       FIG. 18  is an example block diagram of a computer system for implementing any of the operations as discussed herein according to embodiments herein. 
     Any of the resources as discussed herein can be configured to include a processor and executable instructions to carry out the different operations as discussed herein. 
     As shown, computer system  1850  (such as a respective server resource) of the present example can include an interconnect  1811  that couples computer readable storage media  1812  such as a non-transitory type of media (i.e., any type of hardware storage medium) in which digital information can be stored and retrieved, a processor  1813 , I/O interface  1814 , and a communications interface  1817 . I/O interface  814  supports connectivity to repository  1480  and input resource  1892 . 
     Computer readable storage medium  1812  can be any hardware storage device such as memory, optical storage, hard drive, floppy disk, etc. In one embodiment, the computer readable storage medium  1812  stores instructions and/or data. 
     As shown, computer readable storage media  1812  can be encoded with fabrication management application  140 - 1  (e.g., including instructions) to carry out any of the operations as discussed herein. 
     During operation of one embodiment, processor  1813  accesses computer readable storage media  1812  via the use of interconnect  1811  in order to launch, run, execute, interpret or otherwise perform the instructions in fabrication management application  140 - 1  stored on computer readable storage medium  1812 . Execution of the fabrication management application  140 - 1  produces fabrication management process  140 - 2  to carry out any of the operations and/or processes as discussed herein. 
     Those skilled in the art will understand that the computer system  1850  can include other processes and/or software and hardware components, such as an operating system that controls allocation and use of hardware resources to fabrication management application  140 - 1 . 
     In accordance with different embodiments, note that computer system may be or included in any of various types of devices, including, but not limited to, a mobile computer, a personal computer system, a wireless device, base station, phone device, desktop computer, laptop, notebook, netbook computer, mainframe computer system, handheld computer, workstation, network computer, application server, storage device, a consumer electronics device such as a camera, camcorder, set top box, mobile device, video game console, handheld video game device, a peripheral device such as a switch, modem, router, set-top box, content management device, handheld remote control device, any type of computing or electronic device, etc. The computer system  850  may reside at any location or can be included in any suitable resource in any network environment to implement functionality as discussed herein. 
     Functionality supported by the different resources will now be discussed via flowcharts in  FIG. 19 . Note that the steps in the flowcharts below can be executed in any suitable order. 
       FIG. 19  is a flowchart  1900  illustrating an example method according to embodiments. Note that there will be some overlap with respect to concepts as discussed above. 
     In processing operation  1910 , a fabricator (such as executing the fabrication management application  140 - 1 ) of antenna device  100  fabricates first metal layer  120 - 1  such as on substrate  160 . 
     In processing operation  1920 , the fabricator fabricates second metal layer  120 - 2  such as on substrate  170 . 
     In processing operation  1930 , the fabricator spaces the first metal layer  120 - 1  from the second metal layer  120 - 2 . 
     In processing operation  1940 , the fabricator produces the first metal layer  120 - 1  to include an opening (slot  141 ) through which to transmit RF energy to the second metal layer  120 - 2 . The second metal layer  120 - 2  is operable to reflect the RF energy received through the opening back to the first metal layer  120 - 1 . The metal layer  120 - 1  is operable to reflect the RF energy reflected off the second metal layer in a direction past the second metal layer  120 - 2  to a communication medium. 
     FURTHER EXAMPLE EMBODIMENTS 
     Note that further embodiments herein include any of one or more of the following limitations. 
     For example, further embodiments herein include a method comprising: 
     fabricating a first metal layer; fabricating a second metal layer; spacing the first metal layer from the second metal layer; and producing the first metal layer to include an opening through which to transmit RF (Radio Frequency) energy to the second metal layer, the second metal layer operable to reflect the RF energy received through the opening back to the first metal layer, the first metal layer operable to reflect the RF energy off the second metal layer in a direction past the second metal layer to a communication medium. 
     In one embodiment, the method further comprises: fabricating a surface area of the first metal layer to be orthogonal to a direction in which to receive the RF energy through the opening, the surface area of the first metal layer being sufficiently larger than a surface area of the second metal layer to reflect the RF energy past the second metal layer to the communication medium. 
     In accordance with further embodiments, the method further comprises: 
     fabricating a surface area of the first metal layer to be substantially greater than a surface area of the second metal layer, the first metal layer and the second metal layer fabricated to be planar and disposed in parallel with respect to each other. 
     In accordance with yet further embodiments, a surface area of the first metal layer is at least 3 times greater than a surface area of the second metal layer. 
     In accordance with further embodiments, the method includes: fabricating a surface area of the first metal layer to be sufficiently larger than a surface area of the second metal layer such that the combination of the first metal layer and the second metal layer operate in a non-resonant operational mode. 
     In still further embodiments, the opening is a slot, the method further comprising: disposing the second metal layer directly above the slot. 
     In still further embodiments, the slot is fabricated to be wider than the second metal surface. 
     Further method embodiments herein include disposing a lengthwise axis of the slot to be disposed perpendicular to a transmission line on which the RF energy is conveyed from a driver circuit to the opening. 
     In accordance with yet further embodiments, the method includes: fabricating a thickness of a spacer separating the first metal layer and the second metal layer to be less than 25% of a wavelength of the RF energy received through the opening. 
     In accordance with further embodiments, the method includes disposing the first metal layer on a printed circuit board. 
     In accordance with further embodiments, the method includes: fabricating a combination of the first metal layer and the second metal layer combine to form a directional antenna in which a main lobe of the directional antenna extends in an orthogonal direction from a planar surface of the first metal layer. 
     In yet further embodiments, the second metal layer is fabricated as a patch antenna element configured to operate in a reflective mode. 
     In accordance with still further embodiments, the method includes: coupling the first metal layer to a ground reference voltage; receiving a substrate including a first facing and a second facing; and disposing the first metal layer on the first facing of the substrate; disposing a feed ling on the second facing, the feed line operable to convey a signal to the opening to transmit the RF energy. 
     Yet further method embodiments herein include: 
     fabricating a third metal layer to be spaced apart from the first metal layer; and disposing a second opening in the first metal layer, the second opening operable to transmit second RF (Radio Frequency) energy to the third metal layer, the third metal layer operable to reflect the second RF energy received through the second opening back to the first metal layer, the first metal layer operable to reflect the second RF energy from the third metal layer in a direction past the third metal layer to the communication medium. In one embodiment, the third metal layer resides in a same plane as the second metal layer; and the first metal layer is planar, both the second metal layer and the third metal layer parallel to the first metal layer. 
     In accordance with still further embodiments, the method herein includes: disposing a substrate between the first metal layer and a combination of the second metal layer and the third metal layer; fabricating a fifth metal layer on the substrate to be disposed between the first metal layer and the third metal layer; and fabricating a sixth metal layer on the substrate to be disposed between the first metal layer and the fourth metal layer. 
     In yet further embodiments, a combination of the first opening, the first metal layer, and the second metal layer are operable to output the first RF energy at a first carrier frequency; and a combination of the second opening, the first metal layer, and the third metal layer are operable to support output the first RF energy at a second carrier frequency. 
     Yet further method embodiments herein include: fabricating the second metal layer as a first patch antenna element operable to support emission of the first RF energy; and fabricating the third metal layer as a second patch antenna element of multiple patch antenna elements that are collectively operable to support emission of the second RF energy. Additionally, method embodiments includes: fabricating the first patch antenna element to be substantially larger in surface area size than the second patch antenna element. 
     Note again that techniques as discussed herein are well suited for use in different types of antenna devices. However, it should be noted that embodiments herein are not limited to use in such applications and that the techniques discussed herein are well suited for other applications as well. 
     Based on the description set forth herein, numerous specific details have been set forth to provide a thorough understanding of claimed subject matter. However, it will be understood by those skilled in the art that claimed subject matter may be practiced without these specific details. In other instances, methods, apparatuses, systems, etc., that would be known by one of ordinary skill have not been described in detail so as not to obscure claimed subject matter. Some portions of the detailed description have been presented in terms of algorithms or symbolic representations of operations on data bits or binary digital signals stored within a computing system memory, such as a computer memory. These algorithmic descriptions or representations are examples of techniques used by those of ordinary skill in the data processing arts to convey the substance of their work to others skilled in the art. An algorithm as described herein, and generally, is considered to be a self-consistent sequence of operations or similar processing leading to a desired result. In this context, operations or processing involve physical manipulation of physical quantities. Typically, although not necessarily, such quantities may take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared or otherwise manipulated. It has been convenient at times, principally for reasons of common usage, to refer to such signals as bits, data, values, elements, symbols, characters, terms, numbers, numerals or the like. It should be understood, however, that all of these and similar terms are to be associated with appropriate physical quantities and are merely convenient labels. Unless specifically stated otherwise, as apparent from the following discussion, it is appreciated that throughout this specification discussions utilizing terms such as “processing,” “computing,” “calculating,” “determining” or the like refer to actions or processes of a computing platform, such as a computer or a similar electronic computing device, that manipulates or transforms data represented as physical electronic or magnetic quantities within memories, registers, or other information storage devices, transmission devices, or display devices of the computing platform. 
     While this disclosure has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present application as defined by the appended claims. Such variations are intended to be covered by the scope of this present application. As such, the foregoing description of embodiments of the present application is not intended to be limiting. Rather, any limitations to the invention are presented in the following claims.