The present disclosure generally relates to antenna assemblies configured for reception of television signals, such as high definition television (HDTV) signals.
The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Many people enjoy watching television. Recently, the television-watching experience has been greatly improved due to high definition television (HDTV). A great number of people pay for HDTV through their existing cable or satellite TV service provider. In fact, many people are unaware that HDTV signals are commonly broadcast over the free public airwaves. This means that HDTV signals may be received for free with the appropriate antenna.
According to various aspects, exemplary embodiments are provided of antenna assemblies. In one exemplary embodiment, an antenna assembly generally includes at least one antenna element having first and second electrical paths. The antenna assembly may also include at least one reflector element spaced-apart from the antenna element for reflecting electromagnetic waves generally towards the antenna element.
Further aspects and features of the present disclosure will become apparent from the detailed description provided hereinafter. In addition, any one or more aspects of the present disclosure may be implemented individually or in any combination with any one or more of the other aspects of the present disclosure. It should be understood that the detailed description and specific examples, while indicating exemplary embodiments of the present disclosure, are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
The following description is merely exemplary in nature and is in no way intended to limit the present disclosure, application, or uses.
As shown in
In one example, the antenna assembly 100 may include a 75-ohm RG6 coaxial cable 124 fitted with an F-Type connector (although other suitable communication links may also be employed). Alternative embodiments may include other coaxial cables or other suitable communication links.
As shown in
In some embodiments, the tapered loop antenna element has an outer diameter of about two hundred twenty millimeters and an inner diameter of about eighty millimeters. Some embodiments include the inner diameter being offset from the outer diameter such that the center of the circle defined generally by the inner perimeter portion 144 (the inner diameter's midpoint) is about twenty millimeters below the center of the circle defined generally by the outer perimeter portion 140 (the outer diameter's midpoint). Stated differently, the inner diameter may be offset from the outer diameter such that the inner diameter's midpoint is about twenty millimeters below the outer diameter's midpoint. The offsetting of the diameters thus provides a taper to the tapered loop antenna element 104 such that it has at least one portion (a top portion 126 shown in
With continued reference to
The end portions 128 include fastener holes 132 in a pattern corresponding to fastener holes 136 of the PCB balun 112. Accordingly, mechanical fasteners (e.g., screws, etc.) may be inserted through the fastener holes 132, 136 after they are aligned, for attaching the PCB balun 112 to the tapered loop antenna element 104. Alternative embodiments may have differently configured fastener holes (e.g., more or less, different shapes, different sizes, different locations, etc.). Still other embodiments may include other attachment methods (e.g., soldering, etc.).
As shown in FIGS. 4 and 7-10, the illustrated tapered loop antenna element 104 is substantially planar with a generally constant or uniform thickness. In one exemplary embodiment, the tapered loop antenna element 104 has a thickness of about 3 millimeters. Other embodiments may include a thicker or thinner antenna element. For example, some embodiments may include an antenna element with a thickness of about 35 micrometers (e.g., 1 oz copper, etc.), where the antenna element is mounted, supported, or installed on a printed circuit board. Further embodiments may include a free-standing, self-supporting antenna element made from aluminum, copper, etc. having a thickness between about 0.5 millimeters to about 5 millimeters, etc. In another exemplary embodiment, the antenna element comprises a relatively thin aluminum foil that is encased in a supporting plastic enclosure, which has been used to reduce material costs associated with the aluminum.
Alternative embodiments may include an antenna element that is configured differently than the tapered loop antenna element 104 shown in the figures. For example, other embodiments may include a non-tapered loop antenna element having a centered (not offset) opening. Additional embodiments may include a loop antenna element that defines a full generally circular loop or hoop without spaced-apart free end portions 128. Further embodiments may include an antenna element having an outer periphery/perimeter portion, inner periphery/perimeter portion, and/or opening sized or shaped differently, such as with a non-circular shape (e.g., ovular, triangular, rectangular, etc.). The antenna element 104 (or any portion thereof) may also be provided in various configurations (e.g., shapes, sizes, etc.) depending at least in part on the intended end-use and signals to be received by the antenna assembly.
A wide range of materials may be used for the antenna element 104. By way of example only, the tapered loop antenna element 104 may be formed from a metallic electrical conductor, such as aluminum, copper, stainless steel or other alloys, etc. In another embodiment, the tapered loop antenna element 104 may be stamped from sheet metal, or created by selective etching of a copper layer on a printed circuit board substrate.
In regard to the size of the reflector and the spacing to the antenna element, the inventors hereof note the following. The size of the reflector and the spacing to the antenna element strongly impact performance. Placing the antenna element too close to the reflector provides an antenna with good gain, but narrows impedance bandwidth and poor VSWR (voltage standing wave ratio). Despite the reduced size, such designs are not suitable for the intended broadband application. If the antenna element is placed too far away from the reflector, the gain is reduced due to improper phasing. When the antenna element size and proportions, reflector size, baffle size, and spacing between antenna element and reflector are properly chosen, there is an optimum configuration that takes advantage of the near zone coupling with the electrically small reflector element to produce enhanced impedance bandwidth, while mitigating the effects of phase cancellation. The net result is an exemplary balance between impedance bandwidth, directivity or gain, radiation efficiency, and physical size.
In this illustrated embodiment, the reflector 108 is generally square with four perimeter sidewall portions 164. Alternative embodiments may include a reflector with a different configuration (e.g., differently shaped, sized, less sidewall portions, etc.). The sidewalls may even be reversed so as to point opposite the antenna element. The contribution of the sidewalls is to slightly increase the effective electrical size of the reflector and improve impedance bandwidth.
Dimensionally, the reflector 108 of one exemplary embodiment has a generally square surface 160 with a length and width of about 228 millimeters. Continuing with this example, the reflector 108 may also have perimeter sidewall portions 164 each with a height of about 25.4 millimeters relative to the surface 160. The dimensions provided in this paragraph (as are all dimensions set forth herein) are mere examples provided for purposes of illustration only, as any of the disclosed antenna components herein may be configured with different dimensions depending, for example, on the particular application and/or signals to be received or transmitted by the antenna assembly. For example, another embodiment may include a reflector 108 having a baffle, lip, or perimeter sidewall portions 164 having a height of about ten millimeters. Another embodiment may have the reflector 108 having a baffle, lip in the opposite direction to the antenna element. In such embodiment, it is possible to also add a top to the open box, which may serve as a shielding enclosure for a receiver board or other electronics.
With further reference to
As shown in
As shown in
As shown by
The housing 116 may be formed from various materials. In some embodiments, the housing 116 is formed from plastic. In those embodiments in which the antenna assembly is intended for use as an outdoor antenna, the housing may be formed from a weather resistant material (e.g., waterproof and/or ultra-violet resistant material, etc.). In addition, the housing 116 (or bottom portion thereof) may also be formed from a material so as to provide the bottom surface of the housing 116 with a relatively high coefficient of friction. This, in turn, would help the antenna assembly 100 resist sliding relative to the surface (e.g., top surface of television as shown in
In some embodiments, the antenna assembly may also include a digital tuner/converter (ATSC receiver) built into or within the housing. In these exemplary embodiments, the digital tuner/converter may be operable for converting digital signals received by the antenna assembly to analog signals. In one exemplary example, a reflector with a reversed baffle and cover may serve as a shielded enclosure for the ATSC receiver. The shielded box reduces the effects of radiated or received interference upon the tuner circuitry. Placing the tuner in this enclosure conserves space and eliminates (or reduces) the potential for coupling between the antenna element and the tuner, which may otherwise negatively impact antenna impedance bandwidth and directivity.
In various embodiments, the antenna assembly 100 is tuned (and optimized in some embodiments) to receive signals having a frequency associated with high definition television (HDTV) within a frequency range of about 470 megahertz and about 690 megahertz. In such embodiments, narrowly tuning the antenna assembly 100 for receiving these HDTV signals allows the antenna element 104 to be smaller and yet still function adequately. With its smaller discrete physical size, the overall size of the antenna assembly 100 may be reduced so as to provide a reduced footprint for the antenna assembly 100, which may, for example, be advantageous when the antenna assembly 100 is used indoors and placed on top of a television (e.g.,
Exemplary operational parameters of the antenna assembly 100 will now be provided for purposes of illustration only. These operational parameters may be changed for other embodiments depending, for example, on the particular application and signals to be received by the antenna assembly.
In some embodiments, the antenna assembly 100 may be configured so as to have operational parameters substantially as shown in
In addition,
In addition, an antenna assembly may also be configured with fairly forgiving aiming. In such exemplary embodiments, the antenna assembly would thus not have to be re-aimed or redirected each time the television channel was changed.
As another example,
In this example embodiment of the antenna assembly 800, the rotatably convertible support 888 allows the antenna assembly 800 to be supported on a horizontal surface from a vertical surface depending on whether the support 888 is in a first or second configuration. For example,
By way of example, a user may rotate the support 888 to convert the support 888 from the first configuration (
With continued reference to
The support 888 also include a second stop 893 (
In addition helping retain the support 888 in either the first or second configuration, the stops may also help provide a tactile and/or audible indication to the user to stop rotating the upper or lower portion of the support 888 relative to the other portion. For example, as a user is reconfiguring or converting the support 888 from the first or second configuration to the other configuration, the user may feel and/or hear an audible click as the corresponding first or second stop 890, 893 is engaged into the corresponding opening 891, 892.
As shown in
The antenna assemblies 300 (
Other exemplary embodiments of antenna assemblies for mounting outdoors are illustrated in
The antenna assemblies 500 and 600 include reflectors 508 and 608. Unlike the generally solid planar surface of reflectors 108 and 208, the reflectors 508 and 608 have a grill or mesh surface 560 and 660. The reflector 508 also includes two perimeter flanges 564, while the reflector 608 includes two perimeter flanges 664. A mesh reflector is generally preferred for outdoor applications to reduce wind loading. With outdoor uses, size is generally less important such that the mesh reflector may be made somewhat larger than the equivalent indoor models to compensate for the inefficiency of the mesh. The increased size of the mesh reflector also removes or reduces the need for a baffle, which is generally more important on indoor models that tend to be at about the limit of the size versus performance curves.
Any of the various embodiments shown in
According to some embodiments, an antenna element for signals in the very high frequency (VHF) range (e.g., 170 Megahertz to 216 Megahertz, etc.) may be less circular in shape but still based on an underlying electrical geometry of antenna elements disclosed herein. A VHF antenna element, for example, may be configured to provide electrical paths of more than one length along an inner and outer periphery of the antenna element. The proper combination of such an element with an electrically small reflector may thus result in superior balance of directivity, efficiency, bandwidth, and physical size as what may be achieved in other example antenna assemblies disclosed herein.
For example,
The antenna element 704 has an outer periphery or perimeter portion 740 and an inner periphery or perimeter portion 744. The outer periphery or perimeter portion 740 is generally rectangular. The inner periphery or perimeter portion 744 is also generally rectangular. In addition, the antenna element 704 also includes a tuning bar 793 disposed or extending generally between the two side members 794 of the antenna element 704. The tuning bar 793 is generally parallel with the top member 795 and bottom members 796 of the antenna element 704. The tuning bar 793 extends across the antenna element 704, such that the antenna element 704 includes a lower generally rectangular opening 748 and an upper generally rectangular opening 749. The antenna element 704 further includes spaced-apart end portions 728.
With the tuning bar 793, the antenna element 704 includes first and second electrical paths of different lengths, where the shorter electrical path includes the tuning bar 793 and the longer electrical path does not. The longer electrical path is defined by an outer loop of the antenna element 704, which includes the antenna element's spaced-apart end portions 728, bottom members 796, side members 794, and top member 795. The shorter electrical path is defined by an inner loop of the antenna element 704, which includes the antenna element's spaced-apart end portions 728, bottom members 796, portions of the side members 794 (the portions between the tuning bar 793 and bottom members 796), and the tuning bar 793. By a complex coupling theory, the electrical paths defined by the inner and outer loops of the antenna element 704 allow for efficient operation within the VHF bandwidth range of about 170 Megahertz to about 216 Megahertz in some embodiments. With the greater efficiency, the size of the antenna assembly may thus be reduced (e.g., 75% size reduction, etc.) and still provide satisfactory operating characteristics.
The tuning bar 793 may be configured (e.g., sized, shaped, located, etc.) so as to provide impedance matching for the antenna element 704. In some example embodiments, the tuning bar 793 may provide the antenna element 704 with a more closely matched impedance to a 300 ohm transformer.
In one particular example, the end portions 728 of the antenna element 704 are spaced apart a distance of about 2.5 millimeters. By way of further example, the antenna element 704 may be configured to have a width (from left to right in
With continued reference to
Accordingly, embodiments of the present disclosure include antenna assemblies that may be scalable to any number of (one or more) antenna elements depending, for example, on the particular end-use, signals to be received or transmitted by the antenna assembly, and/or desired operating range for the antenna assembly. By way of example only, another exemplary embodiment of an antenna assembly includes four tapered loop antenna elements, which are collectively operable for improving the overall range of the antenna assembly.
Other embodiments relate to methods of making and/or using antenna assemblies. Various embodiments relate to methods of receiving digital television signals, such as high definition television signals within a frequency range of about 174 megahertz to about 216 megahertz and/or a frequency range of about 470 megahertz to about 690 megahertz. In one example embodiment, a method generally includes connecting at least one communication link from an antenna assembly to a television for communicating signals to the television that are received by the antenna assembly. In this method embodiment, the antenna assembly (e.g., 100, etc.) may include at least one antenna element (e.g., 104, etc.) and at least one reflector element (e.g., 108, etc.). In some embodiments, there may be a free-standing antenna element without any reflector element, where the free-standing antenna element may provide good impedance bandwidth, but low directivity for very compact solutions that work in high signal areas. In another example, a method may include rotating a portion of a support (e.g., support 888, etc.) to a first or a second configuration, where the support in the first configuration allows an antenna assembly to be supported on a horizontal surface and the support in the second configuration allows the antenna assembly to be supported on a vertical surface.
The antenna assembly may include a balun (e.g., 112, etc.) and a housing (e.g., 116, etc.). The antenna assembly may be operable for receiving high definition television signals having a frequency range of about 470 megahertz and about 690 megahertz. The antenna element may have a generally annular shape with an opening (e.g., 148, etc.). The antenna element 104 (along with reflector size, baffle, and spacing) may be tuned to at least one electrical resonant frequency for operating within a bandwidth ranging from about 470 megahertz to about 690 megahertz. The reflector element may be spaced-apart from the antenna element for reflecting electromagnetic waves generally towards the antenna element and generally affecting impedance bandwidth and directionality. The antenna element may include spaced-apart first and second end portions (e.g., 128, etc.), a middle portion (e.g., 126, etc.), first and second curved portions (e.g., 150, 152, etc.) extending from the respective first and second end portions to the middle portion such that the antenna element's annular shape and opening are generally circular. The first and second curved portions may gradually increase in width from the respective first and second end portions to the middle portion such that the middle portion is wider than the first and second end portions and such that an outer diameter of the antenna element is offset from a diameter of the generally circular opening. The first curved portion may be a mirror image of the second curved portion. A center of the generally circular opening may be offset from a center of the generally circular annular shape of the antenna element. The reflector element may include a baffle (e.g., 164, etc.) for deflecting electromagnetic waves. The baffle may be located at least partially along at least one perimeter edge portion of the reflector element. The reflector element may include a substantially planar surface (e.g., 160, etc.) that is substantially parallel with the antenna element, and at least one sidewall portion (e.g., 164, etc.) extending outwardly relative to the substantially planar surface generally towards the tapered loop antenna element. In some embodiments, the reflector element includes sidewall portions along perimeter edge portions of the reflector element, which are substantially perpendicular to the substantially planar surface of the reflector element, whereby the sidewall portions are operable as a baffle for deflecting electromagnetic wave energy.
Embodiments of an antenna assembly disclosed herein may be configured to provide one or more of the following advantages. For example, embodiments disclosed herein may provide antenna assemblies that are physically and electrically small but still capable of operating and behaving similar to physically larger and electrically larger antenna assemblies. Exemplary embodiments disclosed may provide antenna assemblies that are relatively small and unobtrusive, which may be used indoors for receiving signals (e.g., signals associated with digital television (of which high definition television signals are a subset), etc.). By way of further example, exemplary embodiments disclosed herein may be specifically configured for reception (e.g., tuned and/or targeted, etc.) for use with the year 2009 digital television (DTV) spectrum of frequencies (e.g., HDTV signals within a first frequency range of about 174 megahertz and about 216 megahertz and signals within a second frequency range of about 470 megahertz and about 690 megahertz, etc.). Exemplary embodiments disclosed herein may thus be relatively highly efficient (e.g., about 90 percent, about 98 percent at 545 MHz, etc.) and have relatively good gain (e.g., about eight dBi maximum gain, excellent impedance curves, flat gain curves, relatively even gain across the 2009 DTV spectrum, relatively high gain with only about 25.4 centimeter by about 25.4 centimeter footprint, etc.). With such relatively good efficiency and gain, high quality television reception may be achieved without requiring or needing amplification of the signals received by some exemplary antenna embodiments. Additionally, or alternatively, exemplary embodiments may also be configured for receiving VHF and/or UHF signals.
Exemplary embodiments of antenna assemblies (e.g., 100, 200, etc.) have been disclosed herein as being used for reception of digital television signals, such as HDTV signals. Alternative embodiments, however, may include antenna elements tuned for receiving non-television signals and/or signals having frequencies not associated with HDTV. Other embodiments may be used for receiving AM/FM radio signals, UHF signals, VHF signals, etc. Thus, embodiments of the present disclosure should not be limited to receiving only television signals having a frequency or within a frequency range associated with digital television or HDTV. Antenna assemblies disclosed herein may alternatively be used in conjunction with any of a wide range of electronic devices, such as radios, computers, etc. Therefore, the scope of the present disclosure should not be limited to use with only televisions and signals associated with television.
Numerical dimensions and specific materials disclosed herein are provided for illustrative purposes only. The particular dimensions and specific materials disclosed herein are not intended to limit the scope of the present disclosure, as other embodiments may be sized differently, shaped differently, and/or be formed from different materials and/or processes depending, for example, on the particular application and intended end use.
Certain terminology is used herein for purposes of reference only, and thus is not intended to be limiting. For example, terms such as “upper”, “lower”, “above”, “below”, “upward”, “downward”, “forward”, and “rearward” refer to directions in the drawings to which reference is made. Terms such as “front”, “back”, “rear”, “bottom” and “side”, describe the orientation of portions of the component within a consistent, but arbitrary, frame of reference which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and words of similar import. Similarly, the terms “first”, “second” and other such numerical terms referring to structures do not imply a sequence or order unless clearly indicated by the context.
When introducing elements or features and the exemplary embodiments, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of such elements or features. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements or features other than those specifically noted. It is further to be understood that the method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
Disclosure of values and ranges of values for specific parameters (such frequency ranges, etc.) are not exclusive of other values and ranges of values useful herein. It is envisioned that two or more specific exemplified values for a given parameter may define endpoints for a range of values that may be claimed for the parameter. For example, if Parameter X is exemplified herein to have value A and also exemplified to have value Z, it is envisioned that parameter X may have a range of values from about A to about Z. Similarly, it is envisioned that disclosure of two or more ranges of values for a parameter (whether such ranges are nested, overlapping or distinct) subsume all possible combination of ranges for the value that might be claimed using endpoints of the disclosed ranges. For example, if parameter X is exemplified herein to have values in the range of 1-10, or 2-9, or 3-8, it is also envisioned that Parameter X may have other ranges of values including 1-9, 1-8, 1-3, 1-2, 2-10, 2-8, 2-3, 3-10, and 3-9.
The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the gist of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.
Number | Date | Country | Kind |
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PCT/US08/61908 | Apr 2008 | US | national |
This application is a continuation-in-part of presently allowed U.S. patent application Ser. No. 12/050,133 filed Mar. 17, 2008, which, in turn, was a continuation-in-part of U.S. Patent Design Patent Application No. 29/304,423 filed Feb. 29, 2008 (now U.S. Design Pat. No. D598,433 issued Aug. 18, 2009) and also claimed the benefit of U.S. Provisional Patent Application No. 60/992,331 filed Dec. 5, 2007 and U.S. Provisional Patent Application No. 61/034,431 filed Mar. 6, 2008. This application is also a continuation-in-part of U.S. patent application Ser. No. 12/040,464 filed Feb. 29, 2008, which, in turn, claimed the benefit of U.S. Provisional Patent Application No. 60/992,331 filed Dec. 5, 2007. This application is also a continuation-in-part of presently allowed U.S. Design Patent Application No. 29/305,294 filed March 17, 2008, which, in turn, was a continuation-in-part of U.S. patent application Ser. No. 12/040,464 and was a continuation of presently allowed U.S. patent application Ser. No. 12/050,133. This application is a continuation-in-part of PCT International Application No. PCT/US08/061908 filed Apr. 29, 2008, which, in turn, claimed priority to U.S. Provisional Patent Application No. 60/992,331 filed Dec. 5, 2007, U.S. Provisional Patent Application No. 61/034,431 filed Mar. 6, 2008, U.S. patent application Ser. No. 12/040,464 filed Feb. 29, 2008, and U.S. patent application Ser. No. 12/050,133 filed Mar. 17, 2008. The entire disclosures of the above applications are incorporated herein by reference.
Number | Date | Country | |
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60992331 | Dec 2007 | US | |
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60992331 | Dec 2007 | US |
Number | Date | Country | |
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Parent | 12050133 | Mar 2008 | US |
Child | 12606636 | US | |
Parent | 29304423 | Feb 2008 | US |
Child | 12050133 | US | |
Parent | 12040464 | Feb 2008 | US |
Child | 29304423 | US |