Dual-polarization patch antenna system

Abstract

A switchable dual-polarized patch antenna with improved cross-polarization isolation for simultaneously radiating horizontally and vertically polarized signals is described. A planar conductor is arranged with first and second terminals spaced apart vertically on a portion of the planar conductor, radiating a vertically polarized signal component with a 0-degree phase shift from one of the two terminals and a vertically polarized signal component with a 180-degree phase shift from the other of the two terminals. A hybrid coupler can provide the 180-degree phase shift. The horizontally polarized signal is radiated from a third terminal spaced apart horizontally on another portion of the planar conductor and coupled to a horizontally polarized signal source. The direction of the 180-degree phase shift for the first and second components of the vertically polarized signal is selectable. The direction of the phase shift for the horizontally polarized signal is also selectable.

Description

Technical Field

[0001] The present antenna relates to a patch antenna, but is not limited thereto, and particularly relates to a dual-polarization patch antenna that is suitable for telecommunications and improves the cross-polarization separation of simultaneous radiation of horizontal and vertical sine wave signals.

Background Art

[0002] A patch (or microstrip) antenna generally includes a flat metal plate mounted on a larger metal ground plane. The flat metal plate is usually rectangular, and the metal layer is generally separated using a dielectric spacer. The flat metal plate has a length and width optimized to achieve a desired input impedance and frequency response. A dual-polarization patch antenna can be configured to simultaneously radiate sine wave signals of horizontal polarization and vertical polarization. Dual-polarization patch antennas are common because of their simple design, thin profile, light weight, and low cost. Exemplary dual-polarization patch antennas are shown in FIGS. 1A and 1B.

[0003] Furthermore, multiple patch antennas on the same printed circuit board can be used by a high-gain array antenna, a phased array antenna, or a holographic metasurface antenna (HMA), and the radiation waveform beam of a radio frequency (RF) signal or a microwave frequency signal can be electronically formed and / or controlled by a large array of patch antennas. Exemplary HMA antennas and beams of radiation waveforms are shown in FIGS. 1C and 1D. Historically, individual patch antennas have been physically grouped closely together to form and control a beam of the radiation waveform of a sine wave signal of horizontal and / or vertical polarization. However, since the dual-polarization patch antennas used for the radiation of millimeter-wave RF signals are physically close to each other, the cross-polarization isolation of the signals of horizontal and vertical polarization radiated simultaneously may be impaired by mutual coupling. Therefore, new designs are constantly required for performance improvement, reduction of mutual coupling, and further cost reduction. The present invention has been made in view of at least such points, and the object thereof is as follows.

Brief Description of the Drawings

[0004]

Figure 1A

Figure 1B

Figure 1C

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Figure 2F

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Embodiments for Carrying Out the Invention

[0005] The present invention will be described in more detail below with reference to the accompanying drawings, which form a part of this specification and exemplarily show specific embodiments in which the present invention can be implemented. However, the present invention can be embodied in many different forms and should not be construed as limited to the embodiments shown herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of the present invention to those skilled in the art. In particular, the present invention can be embodied as a method or an apparatus. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware forms. Therefore, the following detailed description should not be construed in a limiting sense.

[0006] Throughout this specification and the claims, unless the context clearly dictates otherwise, the following terms take the meanings explicitly associated with them in this specification. As used herein, the phrase "in one embodiment" does not necessarily refer to the same embodiment, although it may. Similarly, as used herein, the phrase "in another embodiment" does not necessarily refer to a different embodiment, although it may. As used herein, the term "or" is an inclusive "or" operator and is synonymous with the term "and / or" unless the context clearly dictates otherwise. The term "based on" is not exclusive and allows for being based on additional factors not described unless the context clearly dictates otherwise. Further, throughout this specification, the meanings of "a", "an", and "the" include plural references. Also, the meaning of "in" includes "in" and "on".

[0007] To provide a basic understanding of some aspects of the present invention, embodiments of the present invention will now be briefly described. This brief description is not intended as an extensive overview. Nor is it intended to identify key or critical elements or to delineate or narrow the scope thereof. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later.

[0008] Briefly stated, various embodiments are directed to an antenna arranged as a dual-polarization patch antenna for simultaneously radiating separate horizontally polarized sine wave signals and vertically polarized sine wave signals having improved cross-polarization separation between the horizontal and vertical polarized sine wave signals. An exemplary patch antenna includes a planar conductor arranged in a radiating dual-polarization mode having a first terminal and a second terminal spaced vertically on the planar conductor to radiate a component of a vertically polarized signal with a 0-degree phase shift from one of two terminals and another component of the vertically polarized signal with a 180-degree phase shift from the other of the two terminals. A vertically polarized sine wave signal source is coupled to the two terminals to provide a first component and a second component of the vertically polarized signal. Further, a hybrid coupler is connected to at least one of the vertically polarized sine wave signal source and the first or second terminal to provide a 180-degree phase shift between the first component and the second component of the vertically polarized signal.

[0009] Also, a horizontally polarized sine wave signal source is coupled to a third terminal spaced horizontally on the planar conductor to provide a horizontally polarized signal that can be simultaneously radiated from the third terminal. The radiation of the first and second components of the vertically polarized signal having a 180-degree phase shift difference improves the cross-polarization separation between the vertically polarized signal and the horizontally polarized signal simultaneously radiated from the dual-polarization patch antenna.

[0010] Furthermore, the direction of the 180-degree phase shift of the first and second components of the vertically polarized signal can be arbitrarily selected by choosing whether either the first component or the second component is coupled in series with a 180-degree hybrid coupler. Also, for the horizontally polarized signal, other 180-degree phase shift directions can be arbitrarily selected.

[0011] In one or more embodiments, the dual-polarization patch antenna includes an opening (hole) formed at the center of a planar conductor. The radiation of the horizontally polarized sine wave signal is controlled by comparing the individual impedance values of two elements. One end of the two elements is coupled by a third terminal located at the center of the opening, and the other ends are separately coupled to opposite edges of the opening. A horizontally polarized sine wave signal source, for example, an alternating current (AC) signal source, is coupled to the third terminal located at the center of the opening. Further, when the impedance values of both elements are substantially equal, the radiation of the provided signal by the antenna and / or the mutual coupling of other signals by the third terminal are invalidated. Also, when the impedance value of one of the two elements is substantially larger than the impedance value of the other element, the provided signal is radiated.

[0012] In one or more embodiments, the positive waveform of the horizontally polarized signal is radiated toward an element having an impedance value that is substantially smaller than the other impedance value of the other element. In this way, the phase of the radiated horizontally polarized signal can be shifted by 180 degrees based on whether one of the two elements provides an impedance value that is substantially smaller than the impedance value provided by the other element.

[0013] In one or more embodiments, the first element provides a fixed impedance value and the second element provides a variable impedance value. Further, the variable impedance value of the second element can be provided by one or more of an electronic switch, a mechanical switch, a variable capacitor, a relay, etc. In one or more embodiments, when the switch is conducting (closed), its variable impedance value is relatively small, for example, 1 ohm, and when the switch is non-conducting (open), the variable impedance value can be infinite. Therefore, when the variable impedance value of the non-conducting switch is substantially larger (infinite) than the fixed impedance value of the first element, the horizontally polarized signal is radiated by the antenna to the third terminal. Conversely, when the switch of the second element is conducting and its variable impedance value is substantially equal to the fixed impedance value, the horizontally polarized signal is not radiated.

[0014] In one or more embodiments, the fixed impedance value can be provided in the manufacture of the dual-polarization patch antenna to a metal wire, metal trace, planar extended segment, resistor, capacitor, inductor, etc. that provides a known (fixed) impedance value between the first or second element, e.g., the third terminal located at the center and the edge of the opening. Further, in one or more embodiments, during the manufacture of the dual-polarization patch antenna, the low value (conductive) of the variable impedance value provided by one of the two elements is selected to be substantially equivalent to the fixed impedance value provided by the other of the two elements or the low value (conductive) of the other variable impedance value. Further, the high value (non-conductive) of the variable impedance value provided by one of the two elements is selected to be substantially greater than the fixed impedance value provided by the other of the two elements or the low value (conductive) of the other variable impedance value.

[0015] In one or more embodiments, the direct current (DC) ground is coupled to one or more portions of the planar conductor so as to assist in impedance matching, radiation pattern, and be part of the bias for one or more elements. Also, in one or more embodiments, the shape of the opening formed in the planar conductor can include rectangle, square, triangle, circle, curve, ellipse, quadrilateral, polygon, etc.

[0016] In one or more embodiments, the length of the opening is one-half of the wavelength (λ) of the signal. Also, in one or more embodiments, the signal is composed of a radio frequency signal, a microwave frequency signal, etc. Further, a horizontally polarized sine wave signal and / or a vertically polarized sine wave signal can be provided by an electronic circuit, a signal generator, a waveguide, etc.

[0017] Furthermore, in one or more embodiments, a holographic metasurface antenna (HMA) is used that employs a plurality of switchable patch antennas as scattering elements and radiates a beam formed and controlled based on the provided AC signal. And any signal radiated by any of the plurality of switchable patch antennas, or by other resonant structures, is not mutually coupled to the switchable patch antennas whose switches are operating in the conductive state (closed state).

[0018] Also, in one or more embodiments, in order to further reduce the mutual coupling between closely located antennas, e.g., an array of antennas in an HMA, the distance between the planar conductors of these antennas can be arranged to be less than or equal to a value obtained by dividing the length of the radiation waveform of the provided signal by 3, and less than or equal to a value obtained by dividing the length of the waveform by 11.

[0019] FIG. 1A shows a schematic side view of an exemplary prior art embodiment of a non-switching dual-polarization patch antenna. Further, FIG. 1B shows a schematic top view of the exemplary embodiment. As shown, the dual-polarization patch antenna is composed of an upper planar (flat) plate 113 of a conductive material such as metal, or a “patch”, mounted on a larger planar plate 114 of metal that operates as a ground plane, and is well-known in the prior art. These two planar conductors are arranged to form a resonant portion of a microstrip transmission line, and the upper planar conductor is arranged to have a length of approximately one-half of the length of the signal waveform assuming that the patch antenna radiates. The vertically polarized sine wave signal input to the upper planar plate 113 is provided to a terminal 112 offset from the center of the upper planar plate. Similarly, the horizontally polarized sine wave signal input to the upper planar plate 113 is separately provided to a terminal 111 offset from the center of the upper planar plate. Radiation of the vertically polarized sine wave signal waveform and the horizontally polarized sine wave signal waveform occurs partly due to discontinuities at the truncated edges of the upper planar conductor (patch). Also, since radiation occurs at the truncated edges of the upper patch, the patch antenna acts slightly larger than its physical dimensions. Therefore, for the patch antenna to resonate (where the capacitive load is equal to the inductive load), the length of the upper planar conductor (patch) is typically arranged to be slightly shorter than one-half of the wavelength of the radiation waveform.

[0020] In some embodiments, when using a dual-polarization patch antenna at microwave frequencies, the wavelengths of the vertically polarized signal and the horizontally polarized signal are short enough that the physical dimensions of the dual-polarization patch antenna can be made small enough to be mounted on a portable wireless device such as a mobile phone. Also, the dual-polarization patch antenna can be manufactured directly on the substrate of a printed circuit board.

[0021] In one or more embodiments, the HMA can generate an object wave using an arrangement of controllable scattering elements (antennas). Also, in one or more embodiments, these controllable antennas can use individual electronic circuits such as variable capacitors having two or more different states. Thus, by changing the state of the electronic circuit for one or more of the controllable antennas, the object wave can be changed. A control function such as a hologram function can be used to define the current state of an individual controllable antenna for a particular object wave. In one or more embodiments, the hologram function can be pre-determined or dynamically created in real-time in response to various inputs and / or conditions. In one or more embodiments, a library of predetermined hologram functions can be provided. In one or more embodiments, any type of HMA capable of generating the beams described herein can be used.

[0022] FIG. 1C shows one embodiment of a prior art HMA in the form of a surface scattering antenna 100 (i.e., HMA) that includes a plurality of scattering elements (antennas) 102a, 102b distributed along a wave propagation structure 104 or other arrangement through which a reference wave 105 can be delivered to the scattering elements. The wave propagation structure 104 can be, for example, a microstrip, coplanar waveguide, parallel plate waveguide, dielectric rod or slab, closed or tubular waveguide, substrate integrated waveguide, or any other structure that can support the propagation of the reference wave 105 along or within the structure. The reference wave 105 is input into the wave propagation structure 104. The scattering elements 102a, 102b can include scattering elements embedded within, disposed on the surface of, or disposed within the evanescent proximity of the wave propagation structure 104. Examples of such scattering elements include those disclosed in U.S. Pat. Nos. 9,385,435, 9,450,310, 9,711,852, 9,806,414, 9,806,415, 9,806,416, and 9,812,779, and U.S. Patent Application Publication Nos. 2017 / 0127295, 2017 / 0155193, and 2017 / 0187123, all of which are hereby incorporated by reference in their entirety. Also, any other suitable type or arrangement of scattering elements can be used.

[0023] The surface scattering antenna can also include at least one feed connector 106 configured to couple the wave propagation structure 104 to a feed structure 108 coupled to a reference wave source (not shown). The feed structure 108 can be any other structure that can provide an electromagnetic signal that can be launched into the wave propagation structure 104 via a transmission line, waveguide, or feed connector 106. The feed connector 106 can be, for example, a coaxial - microstrip connector (e.g., SMA - PCB adapter), coaxial - waveguide connector, mode matching transition, etc.

[0024] The scattering elements 102a, 102b are adjustable scattering antennas having electromagnetic properties adjustable in response to one or more external inputs. The adjustable scattering elements can be elements adjustable in response to a voltage input (e.g., a bias voltage for an active element (varactor, transistor, diode, etc.), or an element incorporating an adjustable dielectric material (ferroelectric or liquid crystal, etc.)), a current input (e.g., direct injection of charge carriers into an active element), an optical input (e.g., illumination of a photoactive material), a field input (e.g., a magnetic field for an element including a non-linear magnetic material), a mechanical input (e.g., MEMS, actuator, hydraulic), or the like. In the schematic example of FIG. 1C, a scattering element adjusted to a first state having a first electromagnetic property is depicted as the first element 102a, and a scattering element adjusted to a second state having a second electromagnetic property is depicted as the second element 102b. The depiction of the scattering elements having first and second states corresponding to the first and second electromagnetic properties is not intended to be limiting. Embodiments can provide scattering elements that are discretely adjustable to select from a discrete plurality of states corresponding to a discrete plurality of different electromagnetic properties, or continuously adjustable to select from a continuum of states corresponding to a continuum of different electromagnetic properties.

[0025] In the example of FIG. 1C, the scattering elements 102a, 102b have first and second couplings to a reference wave 105 that are functions of the first and second electromagnetic properties, respectively. Due to the first and second couplings, the first and second scattering elements 102a, 102b generate a plurality of scattered electromagnetic waves having amplitudes that are functions (e.g., proportional) of their respective first and second couplings in response to the reference wave 105. Further, FIG. 1D shows an exemplary embodiment of a beam of electromagnetic waves generated by the HMA shown in FIG. 1C. The superposition of the scattered electromagnetic waves constitutes, in this example, an electromagnetic wave depicted as an object wave 110 radiated from the surface scattering antenna 100.

[0026] FIG. 1E shows an embodiment of an exemplary dual-polarization surface-scattering antenna having a plurality of variable capacitors to form an exemplary holographic metasurface antenna (HMA). An HMA in the form of a surface-scattering antenna 100' including a plurality of scattering elements (antennas) 102a, 102b distributed along wave-propagation structures 104a and 104b or other arrangements can be sent to the scattering elements through reference waves 105a and 105b. The wave-propagation structures 104a, 104b can be, for example, microstrip, coplanar waveguide, parallel-plate waveguide, dielectric rod or slab, closed or tubular waveguide, substrate-integrated waveguide, or any other structure that can support the propagation of reference waves 105a, 105b along or within the structure. The reference waves 105a and 105b are input into the wave-propagation structures 104a and 104b. The scattering elements 102a, 102b can include scattering elements embedded within, disposed on the surface of, or within the evanescent proximity of the wave-propagation structures 104a, 104b. Also, any other suitable type or arrangement of scattering elements can be used.

[0027] The surface-scattering antenna 100' can also include at least two feed connectors 106a and 106b configured to couple the wave-propagation structures 104a and 104b to feed structures 108a and 108b coupled to a reference-wave source (not shown). The feed structures 108a and 108b can be any other structure that can provide an electromagnetic signal that can be launched into the wave-propagation structures 104a and 104b through transmission lines, waveguides, or the feed connectors 106a and 106b. The feed connectors 106a and 106b can be, for example, coaxial-microstrip connectors (e.g., SMA-PCB adapters), coaxial-waveguide connectors, mode-matching transitions, etc.

[0028] The scattering elements 102a, 102b are adjustable scattering antennas having electromagnetic properties adjustable in response to one or more external inputs. The adjustable scattering elements can be elements adjustable in response to a voltage input (e.g., a bias voltage for an active element (variable capacitor, transistor, diode, etc.), or an element incorporating an adjustable dielectric material (ferroelectric or liquid crystal, etc.)), a current input (e.g., direct injection of charge carriers into an active element), a light input (e.g., illumination of a photoactive material), a field input (e.g., a magnetic field for an element including a nonlinear magnetic material), a mechanical input (e.g., MEMS, actuator, hydraulic), or the like. In the schematic example of FIG. 1E, a scattering element adjusted to a first state having a first electromagnetic property is depicted as the first element 102a, and a scattering element adjusted to a second state having a second electromagnetic property is depicted as the second element 102b. The depiction of the scattering elements having first and second states corresponding to the first and second electromagnetic properties is not intended to be limiting. Embodiments can provide scattering elements that are discretely adjustable to select from a discrete plurality of states corresponding to a discrete plurality of different electromagnetic properties, or continuously adjustable to select from a continuum of states corresponding to a continuum of different electromagnetic properties.

[0029] In the example of FIG. 1E, the scattering elements 102a, 102b each have first and second couplings to reference waves 105a, 105b that are functions of the first and second electromagnetic properties. Due to the first and second couplings, the first and second scattering elements 102a, 102b generate a plurality of scattered electromagnetic waves having amplitudes that are functions (e.g., proportional) of their respective first and second couplings in response to the reference waves 105a, 105b.

[0030] Furthermore, FIG. 1F shows an exemplary embodiment of an independent dual-polarization beam of the electromagnetic waveform pattern radiated by the holographic metasurface antenna (HMA) shown in FIG. 1E. The superposition of the scattered electromagnetic waves constitutes, in this example, the electromagnetic waves depicted as object waves 110a and 110b radiated from the surface scattering antenna 100'.

[0031] Also, as shown in FIGS. 1E and 1F, the HMA100´ is arranged to provide a dual polarization signal, e.g., simultaneous emission of horizontal and vertical polarization signals coupled to the same elements 102a and 102b. In this way, the HMA100´ can generate a separate horizontally polarized beam 110a that can be scanned independently of the vertically polarized beam 110b.

[0032] FIGS. 1C and 1E show a one-dimensional array of the scattering elements 102a, 102b. It will be appreciated that two-dimensional or three-dimensional arrays can also be used. Also, these arrays can have different shapes. Further, the array shown in FIG. 1C is a regular array of the scattering elements 102a, 102b having an equidistant spacing between adjacent scattering elements, but other arrays can be irregular or can have different or variable spacings between adjacent scattering elements. Also, an ASIC (Application Specific Integrated Circuit) 109 can be used to control the operation of the columns of the scattering elements 102a, 102b. Further, a control unit 116 can be used to control the operation of one or more ASICs that control one or more rows within the array.

[0033] The array of the scattering elements 102a, 102b can be used to generate a far-field beam pattern that at least approximates a desired beam pattern by applying a modulation pattern (e.g., a hologram function H) to the scattering elements that receive a reference wave (ψ ref ) from a reference wave source. It will be recognized that the modulation pattern or hologram function is illustrated as a sine wave, but non-sine wave functions (including non-repeating or irregular functions) can also be used.

[0034] In at least some embodiments, the hologram function H (i.e., the modulation function) is the complex conjugate of the reference wave and the object wave, i.e., ψ ref * ψ objIs equal to. In at least some embodiments, the surface scattering antenna can be adjusted to provide, for example, a selected beam direction (e.g., beam steering), a selected beam width or shape (e.g., a fan or pencil beam with a wide or narrow beam width), a selected arrangement of nulls (e.g., null steering), a selected arrangement of multiple beams, a selected polarization state (e.g., linear, circular or elliptical polarization), a selected total phase, or any combination thereof. Alternatively, or additionally, embodiments of the surface scattering antenna can be adjusted to provide a selected near-field radiation profile, e.g., to provide near-field focusing or near-field nulls.

[0035] Also, although not shown, the present invention is not limited to variable capacitance as a control element that enables a signal to be radiated from the scattering element. Rather, many different types of control elements can be employed in this way. For example, in one or more other embodiments, a field effect transistor (FET), a microelectromechanical system (MEMS), a bipolar junction transistor (BJT), etc. can be employed instead to enable the scattering element to turn on and off the emission of a signal.

[0036] Furthermore, the term "dual polarization" is used to refer to two orthogonal polarizations that can simultaneously radiate signals from the same antenna. In this specification, horizontal polarization and vertical polarization are used as two exemplary orthogonal polarizations, but dual polarization applies to any other type of two orthogonal polarizations. For example, a +45-degree tilted polarization and a -45-degree polarization are two orthogonal polarizations that can be provided to simultaneously radiate signals. Also, a left-handed circular polarization and a right-handed circular polarization can be generated by connecting a 90-degree hybrid coupler to two feed lines that provide signals. [Illustrative Operating Environment]

[0037] FIG. 2A shows a schematic top view of an exemplary dual-polarization patch antenna 200A. Two terminals 220A and 222A are vertically spaced on a planar conductor 202, and these are coupled to a vertically polarized sine wave signal source 208. Terminal 224A is horizontally spaced on the planar conductor 202, and these are coupled to a horizontally polarized sine wave signal source 210. Further, a DC ground can be coupled to the planar conductor 202. Also, the planar conductor 202 is mounted on a larger planar conductor 204 that operates as a ground plane for the planar conductor 202.

[0038] Furthermore, at terminal 220A, a component of the vertically polarized signal is radiated with a phase shift of 0 degrees. As shown, terminal 220A is coupled in series with the vertically polarized signal source 208. At terminal 222A, another component of the vertically polarized signal having a phase shift of 180 degrees is radiated. Terminal 222A is coupled in series with a hybrid coupler having a 180-degree phase shift with respect to the vertically polarized signal source 208. Also, a horizontally polarized signal is radiated from terminal 224A coupled in series with the horizontally polarized signal source 210. Further, the two components of the horizontally polarized signal and the vertically polarized signal can be radiated simultaneously by the dual-polarization patch antenna 200A.

[0039] FIG. 2B shows a schematic top view of an exemplary dual-polarization patch antenna 200B. Two terminals 220B and 222B are vertically spaced on a planar conductor 202, and these are separately coupled to a vertically polarized sine wave signal source 208. Terminal 224B is horizontally spaced on the planar conductor 202, and these are coupled to a horizontally polarized sine wave signal source 210. Further, a DC ground can be coupled to the planar conductor 202. Also, the planar conductor 202 is mounted on a larger planar conductor 204 that operates as a ground plane for the planar conductor 202.

[0040] Furthermore, at terminal 220B, a component of the vertically polarized signal is radiated with a phase shift of 0 degrees. As shown, terminal 220B is coupled in series with the vertically polarized signal source 208. At terminal 222B, another component of the vertically polarized signal having a phase shift of 180 degrees is radiated. Terminal 222B is coupled in series with a hybrid coupler having a 180-degree phase shift with respect to the vertically polarized signal source 208.

[0041] Also, a horizontally polarized signal is radiated from terminal 224B coupled in series with the horizontally polarized sine wave signal source 210. Also, terminal 224B operates as an impedance comparator between the impedance value Z1 of the component element 230 and the impedance value Z2 of the component element 232. These component elements are coupled between the central terminal 224B and the opposing edges of the opening 234 located at the center of the planar conductor 202. In one or more embodiments, at least one of the impedance values is variable between a high value and a low value, while the other impedance value is fixed at a low value. In one or more embodiments, one of the impedance values Z1 or Z2 is a fixed impedance value, and the other is a variable impedance value that can be switched between a low value substantially equal to the fixed impedance value and a high value substantially greater than the fixed impedance value. Also, in one or more embodiments, both of the impedance values Z1 and Z2 are variable impedance values. Further, the two components of the horizontally polarized signal and the vertically polarized signal can be radiated simultaneously by the dual-polarized patch antenna 200B.

[0042] FIG. 2C shows a schematic top view of an exemplary dual-polarized patch antenna 200C. Two terminals 220C and 222C are arranged vertically spaced on the planar conductor 202, and these are separately coupled to the vertically polarized sine wave signal source 208. Terminal 224C is arranged horizontally spaced on the planar conductor 202, and these are coupled to the horizontally polarized sine wave signal source 210. Further, a DC ground can be coupled to the planar conductor 202. Also, the planar conductor 202 is mounted on a larger planar conductor 204 that operates as a ground plane for the planar conductor 202.

[0043] Furthermore, at terminal 220C, a component of the vertically polarized signal having either a 0-degree or 180-degree phase shift can be selectively radiated. As shown, terminal 220C is coupled in parallel to hybrid coupler 206 and two switches SW1 and SW2, and is coupled to vertically polarized signal source 208. At terminal 222C, the other component of the vertically polarized signal having either a 0-degree or 180-degree phase shift can be selectively radiated. Terminal 222C is also coupled in parallel to hybrid coupler 206 and two switches SW1 and SW2, and is coupled to vertically polarized signal source 208. The opposite opening and closing of the two switches selects whether terminals 220C and 222C radiate components of the vertically polarized signal, and if so, which of the two terminals radiates the component with a 0-degree phase shift or the other component with a 180-degree phase shift. Also, a horizontally polarized signal is radiated from terminal 224C coupled in series with horizontally polarized sine wave signal source 210. Furthermore, the two components of the horizontally polarized signal and the vertically polarized signal can be radiated simultaneously by dual-polarized patch antenna 200C.

[0044] FIG. 2D shows a schematic top view of an exemplary dual-polarized patch antenna 200D. Two terminals 220D and 222D are vertically spaced apart on planar conductor 202, and these are separately coupled to vertically polarized sine wave signal source 208. Terminal 224D is horizontally spaced apart on planar conductor 202, and these are coupled to horizontally polarized sine wave signal source 210. Furthermore, a DC ground can be coupled to planar conductor 202. Also, planar conductor 202 is mounted on a larger planar conductor 204 that operates as a ground plane for planar conductor 202.

[0045] Furthermore, at terminal 220D, a component of a vertically polarized signal having either a 0-degree or 180-degree phase shift can be selectively radiated. As shown, terminal 220D is coupled in parallel to hybrid coupler 206, two switches SW1 and SW2, and is coupled to vertically polarized signal source 208. At terminal 222D, the other component of the vertically polarized signal having either a 0-degree or 180-degree phase shift can be selectively radiated. Terminal 222D is also coupled in parallel to hybrid coupler 206, two switches SW1 and SW2, and is coupled to vertically polarized signal source 208. The opposite opening and closing of the two switches selects whether terminals 220D and 222D radiate components of the vertically polarized signal, and if so, which of the two terminals radiates the component with a 0-degree phase shift or the other component with a 180-degree phase shift.

[0046] Also, a horizontally polarized signal is radiated from terminal 224D coupled in series with horizontally polarized sine wave signal source 210. Also, terminal 224D operates as an impedance comparator between the impedance value Z1 of component 230 and the impedance value Z2 of component 232. These components are coupled between central terminal 224D and the opposing edges of opening 234 located at the center of planar conductor 202. In one or more embodiments, at least one of the impedance values is variable between a high value and a low value, while the other impedance value is fixed at a low value. In one or more embodiments, one of the impedance values Z1 or Z2 is a fixed impedance value, and the other is a variable impedance value switchable between a low value substantially equal to the fixed impedance value and a high value substantially greater than the fixed impedance value. Also, in one or more embodiments, both of the impedance values Z1 and Z2 are variable impedance values. Further, the two components of the horizontally polarized signal and the vertically polarized signal can be radiated simultaneously by dual-polarized patch antenna 200D.

[0047] FIG. 2E shows a schematic side view of an exemplary switchable dual-polarization patch antenna when the separate impedance values (Z1 and Z2) of element 230 and element 232 are substantially equal to each other at terminal 224E. In this case, the antenna is not radiating a horizontally polarized signal.

[0048] FIG. 2F shows a schematic side view of an exemplary switchable dual-polarization patch antenna, indicating that at terminal 224F, the impedance value Z1 of element 230 is substantially greater than the impedance value Z2 of element 232 (open switch - infinity). Thus, due to the large difference in impedance values, when radiated by the antenna, the waveform of the horizontally polarized signal is provided with a 0-degree phase shift (216a, 216b).

[0049] FIG. 2G shows a schematic side view of an exemplary switchable dual-polarization patch antenna, indicating that the impedance value Z2 of element 230 is substantially greater than the impedance value Z1 of element 232 (open switch - infinity). Thus, due to the large difference in impedance values, when radiated by the antenna, the waveform of the horizontally polarized signal is provided with a 180-degree phase shift (216a´, 216b´). [General Operation]

[0050] FIG. 3 shows a flowchart illustrating the operation of a dual-polarization patch antenna that simultaneously radiates horizontal and vertical polarization signals with improved cross-polarization isolation. Starting from the start block, the process moves to block 302 where a component of the vertically polarized signal with a 0-degree phase shift is provided to the first terminal. At block 304, another component of the same vertically polarized signal with a 180-degree phase shift is provided to the second terminal. Proceeding to block 306, the horizontally polarized signal is provided to the third terminal. Moving to block 308, the two components of the horizontally polarized signal and the vertically polarized signal with a 180-degree phase shift difference are simultaneously radiated by a dual-polarization patch antenna with improved cross-polarization isolation. Next, the process returns to the execution of other operations.

[0051] FIG. 4A shows a flowchart 400 showing the operation of a dual-polarization patch antenna having a switchable element for selecting a phase shift of a horizontally polarized signal in order to improve cross-polarization separation during simultaneous radiation of a vertically polarized signal and a horizontally polarized signal. Shifting from the start block, the process proceeds to block 402 where two impedance elements having substantially equal impedances are coupled to the terminals of an aperture at the center of a planar conductor. The terminals are coupled to a horizontally polarized sine wave signal source, but since the impedance values of the two elements are relatively equal, the horizontally polarized signal is not radiated from the terminals. Shifting to decision block 404, a determination is made as to whether one of the elements is selected and exhibits a substantially greater impedance than the other element, for example, whether one of the elements is a switch that is opened. If the determination is affirmative, the process proceeds to block 406 where the direction of a 180-degree phase shift of the horizontally polarized signal is selected by choosing which of the two elements provides a substantially greater impedance than the other element. At block 408, the selected element provides a substantially greater impedance and the horizontally polarized signal is radiated in the selected direction with a 180-degree phase shift. Next, the process returns to the execution of other operations.

[0052] Figure 4B shows a flowchart 420 of the operation of a dual-polarization patch antenna having a switchable element for selecting a phase shift for the radiation of two components of a vertically polarized signal in order to improve cross-polarization separation during simultaneous radiation of a vertically polarized signal and a horizontally polarized signal. Shifting from the start block, the process proceeds to block 422 where two switches connected in parallel to a vertically polarized sine wave signal source and a hybrid coupler are selectively opened to prevent a vertically polarized signal from being coupled to either of two terminals on the plane of the antenna. When transitioning to decision block 424, a determination is made as to whether to selectively close one of the two switches to enable radiation of the vertically polarized signal. If the determination is affirmative, the process proceeds to block 426 where the direction of a 180-degree phase shift of the vertically polarized signal is selected by choosing which of the two switches to close. At block 428, the selected switch is closed, one component of the vertically polarized signal is coupled to the hybrid coupler, and a 180-degree phase shift is provided when that component is radiated at one terminal. Further, the other components of the vertically polarized signal are provided with a 0-degree phase shift when radiated at the other terminal. Next, the process returns to the execution of other operations.

[0053] Figure 5 shows a schematic diagram of an apparatus for controlling the simultaneous radiation of horizontal and vertical polarization signals by a dual-polarization patch antenna having improved cross-polarization separation according to one or more embodiments of the present invention.

[0054] Figure 5 shows a schematic diagram of an exemplary apparatus 500 used to operate a switchable dual-polarization patch antenna 502. A variable impedance control unit 506 is used to control the conductive and non-conductive states of a switching component (not shown) included in the switchable patch antenna 502 that disables or enables the simultaneous radiation of vertically polarized and horizontally polarized signals by the antenna. The vertically polarized signal and the horizontally polarized signal may be provided by one or more of signal sources 504. Also, a DC ground 508 is coupled to the switchable patch antenna 502.

[0055] It will be understood that each block of the flowchart, and combinations of blocks of the flowchart (or the operations described above with respect to one or more systems or combinations of systems), can be implemented by computer program instructions. These program instructions can be provided to a processor for manufacturing a machine, such that the instructions executed on the processor create means for performing the operations specified in the flowchart block or blocks. The computer program instructions can be executed by a processor to cause a series of operational steps to be performed for generating a computer-implemented process that provides steps for performing the operations specified in the flowchart block or blocks when executed on the processor. Also, the computer program instructions can cause at least some of the operational steps shown in the flowchart blocks to be executed in parallel. Further, some of the steps can be executed across multiple processors, as may occur in a multiprocessor computer system. Additionally, one or more blocks or combinations of blocks illustrated in the flowchart can be executed concurrently with other blocks or combinations of blocks, or in a different order than that illustrated, without departing from the scope or spirit of the present invention.

[0056] Furthermore, in one or more steps or blocks, instead of a computer program, it can be implemented using application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), programmable logic arrays (PALs), etc., or a combination thereof, such as embedded logic hardware. The embedded logic hardware can directly execute the embedded logic to execute some or all of the operations in one or more steps or blocks. Also, in one or more embodiments (not shown), some or all of the operations of one or more steps or blocks can be executed by a hardware microcontroller instead of a CPU. In one or more embodiments, the microcontroller can directly execute its own embedded logic to execute operations and access its internal memory and its external input / output interfaces (e.g., hardware pins and / or a wireless transceiver), such as a system-on-chip (SOC).

[0057] The above specification, examples, and data provide a complete description of the manufacture and use of the present invention. Since many embodiments of the present invention can be made without departing from the spirit and scope of the present invention, the present invention resides in the following appended claims.

Description of Reference Numerals

[0058] 200A Dual-Polarization Patch Antenna 202 Planar Conductor 204 Planar Conductor 208 Vertically Polarized Sinusoidal Signal Source 210 Horizontally Polarized Sinusoidal Signal Source 220A, 222A, 224A Terminals

Claims

1. An apparatus for controlling the emission of a signal, comprising: an antenna, wherein the antenna comprises: a planar conductor electrically insulated from other ground planes; a first signal source providing a vertically polarized signal, wherein a first component of the vertically polarized signal is provided with a 0-degree phase shift at a first terminal, a second component of the vertically polarized signal is provided with a 180-degree phase shift at a second terminal, and the first terminal and the second terminal are vertically spaced apart from each other and individually arranged on a part of the planar conductor; a second signal source providing a horizontally polarized signal to a third terminal, wherein the third terminal is horizontally spaced apart from the first terminal and the second terminal and individually arranged on another part of the planar conductor; an opening located in the other part of the planar conductor, wherein the third terminal is arranged at the center of the other part of the planar conductor; a first element coupled between an edge of the planar conductor and the third terminal, and a second element coupled between an opposite edge of the planar conductor and the third terminal; and when a first impedance value of the first element matches a second impedance value of the second element, the horizontally polarized signal is not radiated by the antenna; when one of the first impedance value or the second impedance value is 1 ohm and the other is infinite, the horizontally polarized signal is radiated by the antenna; the vertically spaced positions of the first terminal and the second terminal and the 180-degree phase shift difference between the first and second components of the vertically polarized signal provide cross-polarization separation when the vertically polarized signal and the horizontally polarized signal are simultaneously radiated by the antenna; an apparatus.

2. A hybrid coupler coupled between the vertical polarization signal and one of the first terminal or the second terminal, the hybrid coupler providing a 180-degree phase shift between the first component and the second component of the vertical polarization signal The apparatus according to claim 1, further comprising **Claim 3** A DC ground coupled to one or more portions of the planar conductor to improve impedance matching and radiation pattern and to provide at least a portion of the bias current to one or more elements of the antenna The apparatus according to claim 1, further comprising **Claim 4** One or more signal sources arranged to provide the horizontal polarization signal and the vertical polarization signal, the one or more signal sources further comprising one or more of a signal generator, a waveguide, or an electronic circuit further comprising The one or more signal sources provide the horizontal polarization signal and the vertical polarization signal at one or more frequencies that are one of a radio signal frequency or a microwave signal frequency The apparatus according to claim 1 **Claim 5** A first switch coupled between the first terminal and the vertical polarization signal, and a second switch coupled between the second terminal and the vertical polarization signal A hybrid coupler coupled in parallel between the first switch and the second switch, the hybrid coupler providing a 180-degree phase shift between the first component and the second component further comprising When the first switch is closed and the second switch is open, the first component of the vertical polarization signal is radiated at the first terminal with a 0-degree phase shift, and the second component of the vertical polarization signal is radiated at the second terminal with a 180-degree phase shift When the first switch is open and the second switch is closed, the first component of the vertical polarization signal is radiated from the first terminal with a 180-degree phase shift, and the second component of the vertical polarization signal is radiated from the second terminal with a 0-degree phase shift. The apparatus according to claim 1.

6. Further comprising a control unit that executes an operation, The operation includes selectively opening one of the first and second switches, closing the other of the first and second switches, and providing the 180-degree phase shift to one of the first component or the second component of the vertical polarization signal. The apparatus according to claim 5.

7. One or more of the first element or the second element provide a variable impedance value using one of a switch, a variable capacitor, or another variable impedance device, according to the apparatus of claim 1.

8. One of the first element or the second element provides a fixed impedance value, according to the apparatus of claim 1.

9. Further comprising a control unit that executes an operation, The operation is, changing at least one of the first impedance value or the second impedance value to match each other, changing at least one of the first impedance value or the second impedance value not to match each other, including, The apparatus according to claim 1.

10. Each of the first element and the second element is arranged to further include one of a switch, an electronic switch, a variable capacitor, a fixed impedance device, or a variable impedance device, according to the apparatus of claim 1.

11. The device according to claim 1, wherein the opening further includes a two-dimensional shape that is one of a rectangle, a square, a triangle, a circle, a curved shape, an ellipse, a quadrilateral, or a polygon.

12. The device according to claim 1, further comprising a holographic metasurface antenna (HMA) including a plurality of the antennas arranged to emit a plurality of vertically polarized signals and horizontally polarized signals in a beam shape.

13. A method for controlling signal radiation by an antenna, comprising: providing a planar conductor electrically insulated from other ground planes; using a first signal source to provide a vertically polarized signal, wherein a first component of the vertically polarized signal is provided to a first terminal with a phase shift of 0 degrees, a second component of the vertically polarized signal is provided to a second terminal with a phase shift of 180 degrees, and the first terminal and the second terminal are spaced apart vertically and individually arranged on a portion of the planar conductor; using a second signal source to provide a horizontally polarized signal to a third terminal, wherein the third terminal is horizontally spaced apart from other portions of the planar conductor and is individually arranged away from the first terminal and the second terminal; using an opening located in the other portion of the planar conductor, wherein the third terminal is arranged at the center of the other portion of the planar conductor; using a first element coupled between an edge of the planar conductor and the third terminal and a second element coupled between an opposite edge of the planar conductor and the third terminal; including when a first impedance value of the first element matches a second impedance value of the second element, the horizontally polarized signal is not radiated by the antenna, and when one of the first impedance value or the second impedance value is 1 ohm and the other is infinite, the horizontally polarized signal is radiated by the antenna; The vertically spaced-apart positions of the first and second terminals individually, and the 180-degree phase shift difference between the first and second components of the vertical polarization signal, provide cross-polarization separation when the vertical polarization signal and the horizontal polarization signal are simultaneously radiated by the antenna. Method.

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