Metasurface antennas and metasurface structures for antennas

Abstract

A metasurface structure for an antenna. The metasurface structure includes a plurality of subwavelength units that can manipulate or control the amplitude, phase, polarization, frequency, and momentum of radiated electromagnetic waves. The metasurface structure can be operably coupled with a waveguide to provide a metasurface antenna. The metasurface structure or the metasurface antenna can be connected with a controller for controlling the metasurface structure or the metasurface antenna.

Description

Technical Field

[0001] The present invention generally relates to metasurface structures for antennas and metasurface antennas including metasurface structures. Background Technology

[0002] Electromagnetic waves (EM) are a fundamental component of various technological fields, including electronics, photonics, telecommunications, and quantum systems.

[0003] Generally speaking, electromagnetic waves have five basic characteristics: polarization. Amplitude A, frequency f, momentum k, and (initial) phase These fundamental properties of electromagnetic waves can be applied to space. It is a function of time t. For example, the electric field of a plane wave can be expressed as...

[0004] Electromagnetic wave-related technologies are closely related to controlling and utilizing these fundamental properties of electromagnetic waves. Traditional electromagnetic wave manipulation techniques mainly rely on the cumulative propagation effect in naturally occurring dielectric materials, such as lenses, optical modulators, and waveplates. These optical components are typically bulky and curved, making them unsuitable for modern integrated electronic and photonic systems. Summary of the Invention

[0005] In a first aspect of the invention, a metasurface structure for an antenna is provided. The metasurface structure includes multiple subwavelength units capable of manipulating or controlling the amplitude, phase, polarization, frequency, and momentum (i.e., all five properties mentioned above) of electromagnetic waves during radiation. The subwavelength units may be referred to as "superatoms." It should be noted that while the metasurface structure includes multiple subwavelength units capable of manipulating or controlling all five listed properties, the metasurface structure does not necessarily operate or control all five properties simultaneously; rather, it can operate or control any one or more (at most, all) of these properties simultaneously. For example, the multiple subwavelength units can be controlled by a controller to manipulate or control the amplitude, phase, polarization, frequency, and / or momentum (e.g., all five properties) of the radiated electromagnetic waves.

[0006] In some implementations, multiple subwavelength units can manipulate or control the amplitude, phase, polarization, frequency, and momentum (i.e., all five properties) of electromagnetic waves.

[0007] In some implementations, multiple subwavelength units can be used to selectively manipulate or control the amplitude, phase, polarization, frequency, and / or momentum of electromagnetic waves. For example, multiple subwavelength units can be operated to manipulate or control only one or a portion of the five characteristics at a time (i.e., not all of them).

[0008] In some implementations, multiple subwavelength units can be used to dynamically manipulate or control the amplitude, phase, polarization, frequency, and / or momentum of electromagnetic waves (i.e., one or more of these five properties).

[0009] In some embodiments, multiple subwavelength units can simultaneously operate or control at least two of the amplitude, phase, polarization, frequency, and momentum of the electromagnetic wave. For example, in some embodiments, multiple subwavelength units can simultaneously operate or control two or more of these five characteristics.

[0010] In some embodiments, multiple subwavelength units can independently manipulate or control at least two of the amplitude, phase, polarization, frequency, and momentum of the electromagnetic wave. In other words, in some embodiments, multiple subwavelength units can independently operate or control two or more of these five characteristics.

[0011] In some embodiments, each of the plurality of subwavelength units can be selectively operated (e.g., controlled and selectively operated) in a first operating state and a second operating state to facilitate manipulation or control of the amplitude, phase, polarization, frequency, and / or momentum of the electromagnetic wave. Each of the plurality of subwavelength units can be selected to operate in one or more other operating states, or can be selected not to operate in one or more other operating states. In some embodiments, the first operating state includes a radiating state, wherein the corresponding subwavelength unit radiates electromagnetic waves; the second operating state includes a non-radiating state, wherein the corresponding subwavelength unit does not radiate electromagnetic waves. In some embodiments, the first operating state includes a first radiating state, and the second operating state includes a second radiating state different from the first radiating state. For example, the first radiating state and the second radiating state may correspond to different electromagnetic wave radiation ranges.

[0012] In some embodiments, multiple subwavelength units are arranged in an array. In some embodiments, the multiple subwavelength units are substantially aligned.

[0013] In some embodiments, multiple subwavelength units can be arranged in a one-dimensional array. In some embodiments, multiple subwavelength units can be arranged in a two-dimensional array. For example, multiple subwavelength units can be arranged generally in one or more rows, one or more columns. The multiple subwavelength units in the array can be spaced evenly or unevenly.

[0014] In some embodiments, each of the plurality of subwavelength units includes: a first slot formed on or in a conductive layer, operable to radiate electromagnetic waves; a second slot formed on or in a conductive layer, operable to radiate electromagnetic waves; a first control device operably coupled to the first slot to facilitate selective control of the first slot in a radiating state (where the first slot radiates electromagnetic waves) and a non-radiating state (where the first slot does not radiate electromagnetic waves); and a second control device operably coupled to the second slot for controlling the second slot to operate selectively in a radiating state (where the second slot radiates electromagnetic waves) and a non-radiating state (where the second slot does not radiate electromagnetic waves). The first and second control devices may be controlled by a controller, respectively. In some examples, each subwavelength unit may selectively operate in two or more of the following operating states: (1) both the first and second slots are in a radiating state; (2) the first slot is in a radiating state while the second slot is in a non-radiating state; (3) the first slot is in a non-radiating state while the second slot is in a radiating state; and (4) both the first and second slots are in a non-radiating state.

[0015] In some embodiments, the first and second grooves are substantially the same in shape and / or size. In some embodiments, the first and second grooves are oriented differently. In some embodiments, both the first and second grooves are annular in shape. For example, the annular shape can be substantially elliptical, substantially circular, substantially oblong, substantially elliptical, substantially triangular, substantially rectangular (e.g., square), substantially polygonal, etc.

[0016] In some embodiments, the first groove (such as a ring) extends generally along a first axis, and the second groove (such as a ring) extends generally along a second axis. The first and second axes may be arranged at a non-zero angle (i.e., not parallel). In some embodiments, the first and second axes may be at an angle of approximately 90 degrees.

[0017] In some implementations, the first slot can be used to radiate electromagnetic waves having a first characteristic polarization state (e.g., a first linear polarization state), and the second slot can be used to radiate electromagnetic waves having a second characteristic polarization state (e.g., a second linear polarization state) orthogonal to the first characteristic polarization state (e.g., the first linear polarization state).

[0018] In some embodiments, the first slots of the plurality of subwavelength units have substantially the same orientation. In some embodiments, the first slots of the plurality of subwavelength units have substantially the same shape and / or size. In some embodiments, the second slots of the plurality of subwavelength units have substantially the same orientation. In some embodiments, the second slots of the plurality of subwavelength units have substantially the same shape and / or size. In some embodiments, the first control devices of the plurality of subwavelength units have substantially the same basic structure. In some embodiments, the second control devices of the plurality of subwavelength units have substantially the same basic structure.

[0019] In some embodiments, the first control device includes at least two control elements operably coupled to the first slot to influence the operation of the first slot, and the second control device includes at least two control elements operably coupled to the second slot to influence the operation of the second slot. The at least two control elements of the first control device and the at least two control elements of the second control device may be controlled by a controller. In one example, the controller may provide a first control signal to control the at least two control elements of the first control device and a second control signal to control the at least two control elements of the second control device.

[0020] In some embodiments, at least two control elements of the first control device include a first semiconductor element and a second semiconductor element, each element being selectively operable in an ON state and an OFF state to influence the operation of the first slot, thereby affecting the operating state of the corresponding subwavelength unit. The first and second semiconductor elements of the first control device may include semiconductor diodes, such as PIN diodes. In some examples, the first and second semiconductor elements of the first control device may be arranged to operate simultaneously in an ON or OFF state.

[0021] In some embodiments, at least two control elements of the second control device include a first semiconductor element and a second semiconductor element, each element being selectively operable in an on-state and an off-state to influence the operation of the second slot, thereby affecting the operating state of the corresponding subwavelength unit. The first and second semiconductor elements of the second control device may include semiconductor diodes, such as PIN diodes. In some examples, the first and second semiconductor elements of the second control device may be arranged to operate simultaneously in an on-state or an off-state.

[0022] In some embodiments, a first semiconductor element of the first control device is connected across a first trench portion of the first trench, and a second semiconductor element of the first control device is connected across a second trench portion of the first trench. In some embodiments, the first trench portion and the second trench portion of the first trench are located on opposite sides of the first trench (e.g., two opposite long sides).

[0023] In some embodiments, a first semiconductor element of the second control device is connected across a first slot portion of the second slot, and a second semiconductor element of the second control device is connected across a second slot portion of the second slot. In some embodiments, the first slot portion of the second slot and the second slot portion of the second slot are located on opposite sides of the second slot (e.g., two opposite long sides).

[0024] In some embodiments, a first semiconductor element and a second semiconductor element of the first control device are arranged substantially along the axis of the first control device. The first semiconductor element and the second semiconductor element of the second control device are also arranged substantially along the axis of the second control device. The axes of the first and second control devices may be arranged at a non-zero angle (i.e., not parallel). In some examples, the axes of the first and second control devices may be arranged at approximately 90 degrees. Optionally, the axis of arrangement of the first control element is substantially perpendicular to the first axis. Optionally, the axis of arrangement of the second control element is substantially perpendicular to the second axis.

[0025] In some embodiments, the first and second semiconductor elements of the first control device are biased in the same bias state. The bias state can be a positive bias state or an unbiased state.

[0026] In some embodiments, the first and second semiconductor elements of the second control device are biased in the same bias state. The bias state can be a positive bias state or an unbiased state.

[0027] In a second aspect of the invention, an antenna is provided that includes the metasurface structure described in the first aspect. The antenna may include one or more of the metasurface structures described in the first aspect.

[0028] In a third aspect of the invention, a metasurface antenna is provided, comprising: a waveguide for guiding electromagnetic waves and a metasurface structure of the first aspect described above, operably coupled to the waveguide. The metasurface structure is used to modulate the electromagnetic waves and radiate the modulated electromagnetic waves from the waveguide. The metasurface antenna may include one or more of the metasurface structures of the first aspect described above.

[0029] In some implementations, the metasurface structure is at least partially integrated with the waveguide.

[0030] In some implementations, the waveguide includes a substrate-integrated waveguide.

[0031] In some embodiments, the substrate-integrated waveguide includes: a dielectric substrate, a first conductive layer disposed on one side of the dielectric substrate, a second conductive layer disposed within or on the dielectric substrate, and a plurality of conductive elements disposed within the dielectric substrate and electrically connecting the first and second conductive layers. The dielectric substrate may include one or more substrate layers. The second conductive layer may be embedded in the dielectric substrate or disposed on the other side of the dielectric substrate. The thickness of the first conductive layer may be uniform or non-uniform. The thickness of the second conductive layer may be uniform or non-uniform. The substrate layers of the dielectric substrate may have uniform or non-uniform thicknesses. The plurality of conductive elements may include metal vias and / or metal pillars that at least partially extend through the dielectric substrate. A metasurface structure is at least partially disposed on or within the first conductive layer (e.g., etched into the first conductive layer). In some embodiments, a first trench and a second trench of a plurality of subwavelength units of the metasurface structure are formed (e.g., etched) in or on the first conductive layer.

[0032] In some implementations, multiple conductive elements are arranged in multiple rows (e.g., multiple generally parallel rows).

[0033] In some implementations, each of the multiple subwavelength units of the metasurface structure is operatively coupled to two or more conductive elements.

[0034] In some embodiments, the second conductive layer includes a bias circuit having multiple bias circuit portions. Each of the multiple bias circuit portions is operatively coupled to one of a plurality of subwavelength units of the metasurface structure. The bias circuit portions can bias the first and second semiconductor elements of the first control device under the same bias state. The bias circuit portions can bias the first and second semiconductor elements of the second control device under the same bias state.

[0035] In some implementations, waveguides can be used to guide electromagnetic waves, while metasurface structures can be used to radiate modulated electromagnetic waves from the waveguide into free space.

[0036] In some implementations, the waveguide is generally planar.

[0037] In some implementations, electromagnetic waves include guided waves (e.g., in-plane guided waves), while modulated electromagnetic waves include radiating space waves (e.g., out-of-plane propagating waves).

[0038] In some embodiments, the first and second semiconductor elements of the first control device for the plurality of subwavelength units of the metasurface structure, and the first and second semiconductor elements of the second control device, are arranged to be controlled by a controller to selectively operate in an on state and an off state, respectively, to operate accordingly with each of the plurality of subwavelength units (e.g., radiating state and non-radiating state; first and second radiating states, etc.).

[0039] In a fourth aspect of the invention, a metasurface antenna system is provided, comprising the metasurface antenna described in the third aspect above, and a controller operatively coupled to the metasurface antenna to control its operation. The controller may be the controller mentioned in the first aspect above and / or the controller mentioned in the third aspect above.

[0040] The controller may include one or more of the following: CPU, MCU, GPU, logic circuit, Raspberry Pi chip, digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), and / or digital or analog circuits configured to interpret and / or execute program instructions and / or process signals and / or information and / or data. In some embodiments, the controller includes one or more field-programmable gate arrays.

[0041] In some implementations, the controller may provide control signals to the subwavelength units, particularly their control devices / control elements, to influence the operation of the subwavelength units.

[0042] In some implementations, the controller is arranged (e.g., programmed) to provide a set of control signals to multiple subwavelength elements of the metasurface antenna to influence the operation of the multiple subwavelength elements in space and time, thereby facilitating manipulation or control of the amplitude, phase, polarization, frequency, and / or momentum of electromagnetic waves. The set of control signals can provide multiple time-coded sequences to enable or facilitate beam steering, focusing, data communication, etc.

[0043] In a fifth aspect of the invention, a device / system comprising the metasurface structure described in the first aspect is provided. This device / system may be a communication device / system, a sensing device / system, an imaging device / system, an optical device / system, an information processing (e.g., providing) device / system, an information encoding device / system, etc. The device / system may include one or more of the metasurface structures described in the first aspect.

[0044] In a sixth aspect of the invention, an apparatus / system comprising the antenna described in the second aspect is provided. This apparatus / system may be a communication apparatus / system, a sensing apparatus / system, an imaging apparatus / system, an optical apparatus / system, an information processing (e.g., providing) apparatus / system, an information encoding apparatus / system, etc. The apparatus / system may include one or more antennas described in the second aspect.

[0045] In a seventh aspect of the invention, an apparatus / system comprising the metasurface antenna of the third aspect described above is provided. This apparatus / system may be a communication apparatus / system, a sensing apparatus / system, an imaging apparatus / system, an optical apparatus / system, an information processing (e.g., providing) apparatus / system, an information encoding apparatus / system, etc. The apparatus / system may include one or more metasurface antennas of the third aspect described above.

[0046] In an eighth aspect of the invention, an apparatus / system comprising the metasurface antenna system of the fourth aspect described above is provided. This apparatus / system may be a communication apparatus / system, a sensing apparatus / system, an imaging apparatus / system, an optical apparatus / system, an information processing (e.g., providing) apparatus / system, an information encoding apparatus / system, etc. The apparatus / system may include one or more of the metasurface antenna systems of the fourth aspect described above.

[0047] Other features and aspects of the invention will become apparent from the detailed description and accompanying drawings of the specific embodiments. Any feature described herein relating to one aspect or embodiment may be appropriately and suitably combined with any other feature described herein relating to any other aspect or embodiment.

[0048] The degree terms used herein, such as “generally,” “approximately,” “roughly,” or similar terms, are used, depending on the context, to explain one or more of the following: manufacturing tolerances, degradation, trends, tendencies, imperfections in actual conditions, etc. For example, when a value is modified by degree terms such as “approximately,” this expression could include the value ±15%, ±10%, ±5%, ±2%, or ±1%.

[0049] Unless otherwise stated, the terms “connection,” “coupling,” “installation,” or similar terms are intended to include direct and indirect connections, couplings, installations, etc. Attached Figure Description

[0050] Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings:

[0051] Figure 1 This is a schematic diagram of a metasurface structure used for an antenna in some embodiments of the present invention;

[0052] Figure 2 This is a schematic diagram of a metasurface antenna in some embodiments of the present invention;

[0053] Figure 3 This is a block diagram of the controller in some embodiments of the present invention;

[0054] Figure 4A This is a schematic diagram of a metasurface antenna in one embodiment of the present invention;

[0055] Figure 4B yes Figure 4A A partially enlarged image of the metasurface antenna shows the anisotropic superatoms of the metasurface antenna;

[0056] Figure 5 yes Figure 4A Frequency offset measurements of a metasurface antenna at different modulation frequencies in one example;

[0057] Figure 6 yes Figure 4A A schematic diagram of a metasurface antenna independently manipulating electromagnetic fluctuations in one example;

[0058] Figure 7 It is used in an example Figure 4A A schematic diagram of a metasurface antenna independently manipulating the phase of electromagnetic waves;

[0059] Figure 8 Here is an example showing the use of Figure 4A The situation where metasurface antennas independently manipulate the amplitude of electromagnetic waves;

[0060] Figure 9 This is a schematic diagram illustrating the use of [something] in one example. Figure 4A Metasurface antennas can independently manipulate the polarization of electromagnetic waves;

[0061] Figure 10 This is a schematic diagram illustrating the use of [something] in one example. Figure 4A Metasurface antennas simultaneously manipulate electromagnetic wave characteristics;

[0062] Figure 11 Is using Figure 4A A schematic diagram of an airy beam with a harmonic frequency of m = -1 generated in free space by a metasurface antenna;

[0063] Figure 12 It is to display the required aperture phase profile and Figure 4A A plot of the corresponding normalized time offsets at different locations of the metasurface antenna metaatom in one example;

[0064] Figure 13 These are electric field intensity diagrams measured at different harmonic frequencies on the xz plane;

[0065] Figure 14 yes Figure 4A A schematic diagram of a metasurface antenna focusing light (electromagnetic wave) at a harmonic frequency of m = -1 in one example;

[0066] Figure 15 It is a display Figure 4A The superatomic positions of the metasurface antenna and the required normalized local momentum k x / ξ mThe graph of the functional relationships, where F1 = (-100mm, 80mm), F2 = (-70mm, 80mm), F3 = (-40mm, 80mm), F4 = (-10mm, 80mm), F5 = (20mm, 80mm);

[0067] Figure 16 Here is an example showing the electric field strength measured along a line of z = 80 mm at the m = -1 harmonic frequency as the focal spot scans from F1 to F5.

[0068] Figure 17 These are a series of schematic diagrams showing, in one example, the corresponding measured electric field strengths of focal spots F1 to F5 on the xz plane at the m = -1 harmonic frequency;

[0069] Figure 18 It is a diagram showing the use of in one example. Figure 4A Metasurface antennas directly generate electromagnetic waves carrying information in free space;

[0070] Figure 19 It is a diagram showing the use of in one example. Figure 4A The metasurface antenna directly generates two independently modulated electromagnetic waves, carrying different digital data streams;

[0071] Figure 20 yes Figure 4A A schematic diagram of the corresponding measured radiation modes of the metasurface antenna at harmonic frequencies of m = -1 (CH1) and m = -2 (CH2);

[0072] Figure 21 This is a diagram showing the use of [something] in one example. Figure 4A The inherent directional modulation characteristics of the metasurface antenna at the fundamental frequency;

[0073] Figure 22 It is a schematic diagram showing... Figure 4A The measured radiation pattern of the metasurface antenna, and the measured decoded constellation diagram when the receiver is located in different directions in one example;

[0074] Figure 23 yes Figure 4A A schematic diagram of the configuration of a metasurface antenna in one example;

[0075] Figure 24 This is a schematic diagram showing the representation of the "0 / 1" Spatiotemporal Coding (STC) matrix, which represents... Figure 4A The radiative and nonradiative states of the superatoms in a metasurface antenna during a modulation period;

[0076] Figure 25 It is a schematic diagram showing... Figure 4AThe time series of each superatom of the metasurface antenna in one example with time offset t i ;

[0077] Figure 26 yes Figure 4A A schematic diagram illustrating the working principle of a metasurface antenna, used in one example for wavefront manipulation of harmonic frequencies;

[0078] Figure 27 yes Figure 4A A schematic diagram of a metasurface antenna undergoing frequency shifting in one example;

[0079] Figure 28 It is a schematic diagram showing... Figure 4A In one example, the metasurface antenna converts the guided wave into a propagating wave at the fundamental frequency (m=0);

[0080] Figure 29 It is a schematic diagram showing the randomization of the STC matrix to suppress higher harmonic frequencies in one example;

[0081] Figure 30 It is a diagram showing the use of in one example. Figure 4A The metasurface antenna operates with independent polarization at the fundamental frequency;

[0082] Figure 31 It is a diagram showing the use of an example. Figure 4A The metasurface antenna is independently momentum-controlled at the fundamental frequency;

[0083] Figure 32 It is a diagram showing the use of an example. Figure 4A The metasurface antenna is independently phase-controlled at the fundamental frequency;

[0084] Figure 32 It is used in an example Figure 4A A schematic diagram of a metasurface antenna performing independent phase control of the fundamental frequency;

[0085] Figure 33 It is used in an example Figure 4A A schematic diagram of a metasurface antenna performing independent amplitude operation on the fundamental frequency;

[0086] Figure 34 This is a schematic diagram showing, in one example, the one-to-one mapping between the QPSK symbol set, the transmitted signal set, and the STC matrix set ((m=+1 harmonic frequency radiation)) in a constellation diagram;

[0087] Figure 35It is a schematic diagram showing, in one example, the digital baseband signal, the corresponding modulation free space waveform, and the STC film (fundamental frequency) required for different modulation formats (2ASK, 2PSK, and 16QAM);

[0088] Figure 36 This is a schematic diagram illustrating the use of shared aperture technology in one example to... Figure 4A The metasurface antenna emits two independently modulated electromagnetic waves;

[0089] Figure 37 This is a schematic diagram showing the synthesis process of an STC film used for dual-channel wireless communication in one example;

[0090] Figure 38 This is a schematic diagram of the measurement radiation mode of a general metasurface antenna at harmonic frequencies of m = -1 (CH1) and m = -2 (CH2) (with the main beam directions of CH1 and CH2 pointing at (0°, 30°));

[0091] Figure 39 This is a schematic diagram of the measurement radiation mode of a general metasurface antenna at harmonic frequencies of m = -1 (CH1) and m = -2 (CH2) (the main beam directions of CH1 and CH2 are pointing at (30°, -30°));

[0092] Figure 40 This is a diagram showing the use of [something] in one example. Figure 4A In the BPSK scheme of the metasurface antenna, the two equivalent sinusoidal amplitude envelopes propagated on the fundamental frequency are time-controlled to generate two highly directional beams with a phase difference of 180° in the wide side direction.

[0093] Figure 41 This is a graph showing the relationship between the phase difference and the observation direction θ in two radiation scenarios in one example.

[0094] Figure 42 This is a diagram showing the use of [something] in one example. Figure 4A Metasurface antennas directly generate fundamental frequency BPSK modulated electromagnetic waves;

[0095] Figure 43 yes Figure 4A The theoretical power modes of metasurface antennas and Figure 4A The graph shows the relationship between the error vector magnitude (EVM) associated with the metasurface antenna and the observation direction θ.

[0096] Figure 44 This is a schematic diagram showing, in one example, the receiver being positioned in different directions (the main beam direction of the metasurface antenna is scanned to 30°). Figure 4A Measurement radiation modes and measurement decoding constellation diagrams of metasurface antennas;

[0097] Figure 45 yes Figure 4A A schematic diagram of the measurement radiation mode of the metasurface antenna, and a measurement decoding constellation diagram of the receiver in different directions (the main beam direction of the metasurface antenna is scanned to -30°) in an example;

[0098] Figure 46 This is a schematic diagram of a traditional beam scanning transmission system;

[0099] Figure 47 yes Figure 4A A schematic diagram of the measurement radiation mode of the metasurface antenna operating at the m = -1 harmonic frequency, and a measurement decoding constellation diagram with the receiver located in different directions in one example;

[0100] Figure 48A This is a schematic diagram showing a measurement used in one example. Figure 4A A device for measuring the radiation modes of metasurface antennas;

[0101] Figure 48B yes Figure 4A Photographs of the corresponding measurement setup for the surface antenna radiation mode measurement in the superconducting magnet.

[0102] Figure 49 This is a photo of the measurement setup of a dual-channel wireless communication link test platform as an example;

[0103] Figure 50 yes Figure 4A Theoretical and experimental far-field radiation mode diagrams of metasurface antennas under radiation at the m=+1 harmonic frequency;

[0104] Figure 51 This is a schematic diagram showing the STC matrix for polarization control at the m = +1 harmonic frequency. In one example, the polarization includes (|x>, |y>, |u>, |v>, |LCP> and |RCP>).

[0105] Figure 52 This is a schematic diagram showing the STC matrix for polarization control at the m=0 harmonic frequency. In one example, the polarization includes (|x>, |y>, |u>, |v>, |LCP> and |RCP>).

[0106] Figure 53 It's a table, shown in an example. Figure 4A Theoretical and measurement results of six representative polarizations and their components |u> and |u> were obtained from the metasurface antenna. Detailed Implementation

[0107] Figure 1A metasurface structure 102 for use as an antenna in certain embodiments of the present invention is shown. The metasurface structure 102 includes a plurality of subwavelength units (e.g., superatoms, denoted as "U") that can be used to manipulate or control the amplitude, phase, polarization, frequency, and / or momentum of radiated electromagnetic waves. Depending on the embodiment, the metasurface structure 102 can manipulate or control one, two, three, four, or all of the five properties (amplitude, phase, polarization, frequency, and momentum). The metasurface structure 102 can be operatively connected to a controller 10. The controller 10 can provide control signals to the metasurface structure 102 to facilitate the manipulation or control of the amplitude, phase, polarization, frequency, and / or momentum of the electromagnetic waves.

[0108] In some embodiments, the metasurface structure 102 or the subwavelength unit can selectively manipulate or control the amplitude, phase, polarization, frequency, and / or momentum of the electromagnetic wave. Depending on the embodiment, the metasurface structure 102 can selectively manipulate or control one, two, three, or four of the five listed properties (amplitude, phase, polarization, frequency, and momentum) simultaneously.

[0109] In some embodiments, the metasurface structure 102 or subwavelength unit can dynamically manipulate or control the amplitude, phase, polarization, frequency, and / or momentum of electromagnetic waves. Depending on the embodiment, the metasurface structure 102 can dynamically manipulate or control one, two, three, or four of the five listed properties (amplitude, phase, polarization, frequency, and momentum).

[0110] In some embodiments, the metasurface structure 102 or subwavelength unit can simultaneously manipulate or control the amplitude, phase, polarization, frequency, and / or momentum of electromagnetic waves. Depending on the embodiment, the metasurface structure 102 can simultaneously manipulate or control two, three, four, or all five listed characteristics (amplitude, phase, polarization, frequency, and momentum).

[0111] In some embodiments, the metasurface structure 102 or the subwavelength unit can independently manipulate or control the amplitude, phase, polarization, frequency, and / or momentum of the electromagnetic wave. Depending on the embodiment, the metasurface structure 102 can independently manipulate or control at least two of the five listed properties (amplitude, phase, polarization, frequency, and momentum).

[0112] In some implementations, the metasurface structure 102 or the subwavelength unit can independently, simultaneously and dynamically control at least two of the five listed properties (amplitude, phase, polarization, frequency and momentum).

[0113] Each subwavelength unit of the metasurface structure 102 can selectively operate in different operating states (e.g., controlled by the controller 10 to operate in different operating states) to manipulate or control the amplitude, phase, polarization, frequency, and / or momentum of electromagnetic waves. For example, each subwavelength unit can selectively operate in a radiating state (radiating electromagnetic waves) and a non-radiating state (not radiating electromagnetic waves). For example, each subwavelength unit can selectively be in a strong radiating state and a weak radiating state. The electromagnetic waves radiated by the various subwavelength units of the metasurface structure 102 can be combined in time and space to form the resulting electromagnetic wave.

[0114] In some embodiments, the subwavelength units of the metasurface structure 102 can be arranged in an array, such as a one-dimensional array or a two-dimensional array. For example, the subwavelength units can be arranged generally in one or more rows, one or more columns. The subwavelength units can be spaced uniformly or non-uniformly.

[0115] The subwavelength units of the metasurface structure 102 can have substantially the same structure. In some embodiments, each subwavelength unit includes: at least two trenches formed on or in a conductive layer, each trench being operatively radiating electromagnetic waves, and a respective control device, each control device being operatively coupled to one of the at least two trenches to facilitate selective control of the operation of the respective trench in a radiating state (radiating electromagnetic waves) and a non-radiating state (not radiating electromagnetic waves).

[0116] In some examples, at least two slots of the same subwavelength unit may be fully radiating to radiate electromagnetic waves. In some examples, only one or part of the at least two slots of the same subwavelength unit may be radiating to radiate electromagnetic waves. In some examples, at least two slots of the same subwavelength unit may be fully non-radiating. A control device may be operatively connected to controller 10 and thus controlled by controller 10. In some embodiments, at least two slots of the same subwavelength unit may have substantially the same shape and / or size. For example, the shape of each slot in the at least two slots of the same subwavelength unit may be annular, substantially elliptical, substantially circular, substantially oblong, substantially elliptical, substantially triangular, substantially rectangular (e.g., square), substantially polygonal, etc. In some embodiments, each slot in the at least two slots of the same subwavelength unit may have different orientations. For example, one slot may extend substantially along an axis, while the other slot may extend substantially along another axis at an angle (e.g., acute angle, right angle, etc.) to the axis. In one example, the angle is approximately 90 degrees. In some embodiments, each of at least two slots in the same subwavelength unit can radiate electromagnetic waves in its respective polarization state. For example, one slot may be used to radiate electromagnetic waves having a first characteristic polarization state (such as a first linear polarization state), while the other slot may be used to radiate electromagnetic waves having a second characteristic polarization state (such as a second linear polarization state) orthogonal to the first characteristic polarization state. For each subwavelength unit, its control device may include at least two control elements operatively coupled to the corresponding slot for influencing the operation of the corresponding slot. The at least two control elements of the control device may be controlled by controller 10. For example, the controller may provide control signals to one of the control devices respectively.

[0117] The control elements of the control device can be semiconductor elements, each of which can be selectively in an "on" and "off" state to affect the operation of the corresponding slot to which the control element is operatively coupled. In some examples, the semiconductor elements can be semiconductor diodes, such as PIN diodes. In some examples, the semiconductor elements of the same control device in the subwavelength unit can be arranged (e.g., controlled by controller 10) to operate simultaneously in an on or off state. In some embodiments, the semiconductor elements of the same control device in the subwavelength unit are biased in the same bias state (e.g., forward bias, unbiased, etc.). In some embodiments, each control element can be connected across a slot portion of its corresponding slot. For example, each slot can include two control elements, each connected across a slot portion of the slot. The two slot portions can be arranged on opposite long sides of a slot that is annular in shape. In some implementations, for each subwavelength unit, two control elements of one slot are arranged generally along an axis (in some examples, this axis is generally perpendicular to the axis extending from the corresponding slot), while two control elements of the other slot are arranged generally along another axis (in some examples, this axis is generally perpendicular to the axis extending from the corresponding slot), which is at an angle (e.g., an acute angle, a right angle, etc.) to the axis. In one example, this angle is approximately 90 degrees.

[0118] Figure 2 A metasurface antenna 200 according to certain embodiments of the present invention is shown. The metasurface antenna 200 includes a metasurface structure 202 and a waveguide 204 operatively coupled to the metasurface structure. In some embodiments, the metasurface structure 202 is... Figure 1 The metasurface structure 102 (controller 20 can correspond to) Figure 1 (Controller 10 in the middle). Waveguide 204 can be used to guide electromagnetic waves, and metasurface structure 202 can be used to modulate electromagnetic waves and radiate modulated electromagnetic waves.

[0119] In some implementations, waveguide 204 can be used to guide electromagnetic waves, while metasurface structure 202 can be used to radiate modulated electromagnetic waves from the waveguide into free space. For example, the electromagnetic waves can be in-plane waves (such as in-plane guided waves), while the modulated electromagnetic waves can be out-of-plane waves (such as out-of-plane propagating waves).

[0120] In some implementations, the metasurface structure 202 may be integrated at least partially with the waveguide 204.

[0121] Waveguide 204 may be generally planar. For example, waveguide 204 may be a substrate-integrated waveguide. In some embodiments, the substrate-integrated waveguide may include: a dielectric substrate, a conductive layer disposed on one side of the dielectric substrate, another conductive layer disposed in (e.g., embedded therein) or disposed on (e.g., disposed on the other side of the dielectric substrate) the dielectric substrate, and a plurality of conductive elements (vias, holes, pillars, etc.) disposed in the dielectric substrate (e.g., extending at least partially through the dielectric substrate) and electrically connecting the two conductive layers. The thickness of the conductive layers may be uniform or non-uniform. The dielectric substrate may have one or more layers, each with a uniform or non-uniform thickness. The conductive elements may be arranged in multiple rows (e.g., multiple generally parallel rows).

[0122] The metasurface structure 202 is at least partially disposed on or within a conductive layer on one side of the dielectric substrate (e.g., etched into the conductive layer). For example, trenches for the subwavelength units of the metasurface structure 202 may be formed in or on the conductive layer (e.g., etched). In some embodiments, each subwavelength unit of the metasurface structure 202 is operatively coupled to two or more conductive elements (e.g., each trench is operatively coupled to at least one conductive element). Another conductive layer may include a bias circuit having multiple bias circuit portions, each operatively coupled to a respective subwavelength unit of the metasurface structure 202. The bias circuit portions may bias semiconductor elements of the same control device in the corresponding subwavelength units under the same bias state. In some embodiments, the semiconductor elements of the control device for the subwavelength units of the metasurface structure 202 are arranged to be controlled by the controller 20 to selectively operate in an on state and an off state, respectively, to operate each respective subwavelength unit of the metasurface structure 202.

[0123] Figure 3 A controller 300 according to certain embodiments of the present invention is shown. The controller 300 can be used as... Figure 1 Controller 10 or Figure 2 The controller 20 in the middle.

[0124] Controller 300 generally includes suitable components for receiving, storing, and executing appropriate computer instructions, commands, and / or code. The main components of controller 300 are processor 302 and memory 304. Processor 302 may include one or more of the following: CPU, MCU, GPU, logic circuitry, Raspberry Pi chip, digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), or any other digital or analog circuitry configured to interpret and / or execute program instructions and / or process signals and / or information and / or data. Memory 304 may include one or more volatile memories (such as RAM, DRAM, SRAM, etc.), one or more non-volatile memories (such as ROM, PROM, EPROM, EEPROM, FRAM, MRAM, FLASH, SSD, NAND, NVDIMM, etc.), or any combination thereof. Appropriate computer instructions, commands, codes, information, and / or data may be stored in memory 304. Computer instructions for performing or facilitating the performance of embodiments of the methods of the present invention may be stored in memory 304. For example, control signals (e.g., spatiotemporally encoded sequences, spatiotemporally encoded matrices, spatiotemporally encoded films, etc.) used to control the operation of subwavelength units (e.g., their control elements) of the metasurface structure can be stored in memory 304. In some embodiments, processor 302 and memory (storage) 304 can be integrated together (i.e., memory 304 is embedded in processor 302). In some embodiments, processor 302 and memory (storage) 304 can be separate (and operably connected). Controller 300 can establish power and / or data communication with the metasurface structure, for example, via one or more of cables, buses, wires, electrical conductor arrangements, etc. Those skilled in the art will understand that... Figure 3 The controller 300 shown is just an example; in different embodiments, the controller 300 may have different configurations (e.g., including additional components, etc.).

[0125] The controller 300 may be part of a computing system, computing device, etc. It is also understood that any suitable computing system architecture may be used when the methods and systems of the present invention are implemented wholly or partially by a computing system. This may include stand-alone computers, network computers, dedicated or non-dedicated hardware devices, etc. When using the terms "computing system" and "computing device," these terms are intended to include (but are not limited to) any suitable arrangement of computer or information processing hardware capable of performing the described functions.

[0126] The following disclosure relates to some embodiments of the invention, which pertain to metasurface antennas operable to manipulate the fundamental characteristics of electromagnetic waves. These embodiments can be considered as... Figure 1 metasurface structures 102 and / or Figure 2 A more specific implementation of the metasurface antenna 200.

[0127] The inventors of this invention have discovered that metasurfaces can realize wave-matter interaction within ultrathin artificial surfaces, thus providing a paradigm shift for electromagnetic wave manipulation. Furthermore, metasurfaces can manipulate the fundamental properties of electromagnetic waves, potentially revolutionizing various electromagnetic wave-based applications such as optics, telecommunications, materials engineering, and quantum systems. Nevertheless, the inventors have recognized that simultaneously and independently controlling multiple fundamental properties of electromagnetic waves, particularly all of them, with high integrability and / or programmability, is a challenging task. The inventors believe it is necessary to provide a "universal" metasurface capable of simultaneously and independently controlling certain, preferably all, fundamental properties of electromagnetic waves.

[0128] The inventors of this invention recognized through research that, due to various challenges, it remains difficult to realize metasurfaces capable of manipulating all the fundamental properties of electromagnetic waves. For example, most existing metasurfaces are passive, with their functions pre-defined and unchangeable once fabricated. However, many modern electromagnetic wave applications, such as communications, holographic displays, and LiDAR (Light Detection and Ranging), require dynamic, active control to adapt to the environment and / or process information. While some tunable metasurfaces integrating active functional materials have been explored to achieve dynamic wave control in response to external stimuli (including electrical bias, mechanical deformation, optical pumping, and / or thermal excitation), these tunable metasurfaces mostly control only one or two wave characteristics due to insufficient degrees of freedom in component geometry and external control variables, making it impossible to adjust all fundamental properties. Moreover, since the control of these fundamental properties of electromagnetic waves is usually intercoupled, it is difficult to manipulate independent wave characteristics. Although unique geometries and co-optimization with active materials can decouple amplitude and phase modulation, the complexity of the design and insertion loss increase exponentially with increasing degrees of freedom in control.

[0129] The inventors of this invention have realized through research that temporally controlled metasurfaces (STMMs) are a technique that can be used to engineer electromagnetic waves in both space and time. Specifically, temporally controlled metasurfaces can incorporate a time dimension into conventional metasurface designs, thereby enabling various physical phenomena and wave manipulations in frequency-momentum space. However, to date, only limited control of temporally controlled metasurfaces has been verified. The inventors of this invention have recognized that existing temporally controlled metasurface techniques may not be able to utilize radiation apertures to control all the fundamental properties of electromagnetic waves, particularly the inability to achieve simultaneous and independently programmable radiation characteristics.

[0130] The following embodiments of the present invention relate to a universal metasurface antenna capable of dynamically, simultaneously, independently, and precisely controlling all five fundamental properties of radiated electromagnetic waves. In some embodiments, the universal metasurface antenna, capable of controlling all fundamental properties of radiated electromagnetic waves, may control only one or more fundamental properties of the radiated electromagnetic waves. In some embodiments, the universal metasurface antenna can further enhance spatially and temporally varied wave characteristics, thereby enabling the generation of more complex waveforms, beamforming, direct information processing, etc. In some embodiments, the universal metasurface antenna can directly generate modulated electromagnetic waves carrying digital information, thereby fundamentally simplifying the architecture of information transmission systems. In some embodiments, all wave manipulation and information modulation are achieved by spatiotemporally switching the on-off coded states of the metasurface antenna's metaatoms (subwavelength units). The metasurface antennas in these embodiments provide better electromagnetic wave and information manipulation capabilities, which may be particularly useful in applications such as next-generation wireless systems, cognitive sensing, imaging, quantum optics, and quantum information science.

[0131] Figure 4A A metasurface antenna 400 according to one embodiment of the present invention is shown. Figure 4B Showing more details Figure 4A Part of the supersurface antenna 400.

[0132] In this embodiment, the metasurface antenna 400 generally includes a substrate-integrated waveguide 404 and a metasurface structure 402 operatively coupled to the substrate-integrated waveguide 404. The substrate-integrated waveguide 404 can be used to receive and guide in-plane electromagnetic waves (guided waves). The metasurface structure 402 is used to extract and modulate in-plane electromagnetic waves and radiate out-of-plane modulated electromagnetic waves (propagating waves). In this embodiment, the metasurface structure 402 is integrated with the substrate-integrated waveguide 404.

[0133] In this embodiment, as Figure 4B As shown, the substrate integrated waveguide 404 includes a dielectric substrate, an upper conductive layer disposed on top of the dielectric substrate, a lower conductive layer embedded in the dielectric substrate, and multiple rows of parallel metal vias disposed in the dielectric substrate and electrically connecting the two conductive layers.

[0134] In this embodiment, the metasurface structure 402 includes multiple subwavelength units (i.e., superatoms) that can be used to manipulate or control the amplitude, phase, polarization, frequency, and momentum of radiated electromagnetic waves. Because the metasurface structure 402 can manipulate or control all these properties of electromagnetic waves, the metasurface antenna 400 can be referred to as a universal metasurface antenna 400. In this example, the metasurface structure 402 can independently, simultaneously, and dynamically manipulate or control two or more amplitudes, phases, polarizations, frequencies, and momentum of electromagnetic waves for radiation. In one example, each of the multiple subwavelength units can selectively operate in a first operating state and a second operating state (e.g., a radiating state and a non-radiating state, or a stronger radiating state and a weaker radiating state) to facilitate manipulation or control of the amplitude, phase, polarization, frequency, and / or momentum of the electromagnetic waves.

[0135] like Figure 4A As shown, the subwavelength units are generally arranged in an array, and their structures are largely identical. Specifically, each subwavelength unit includes: two generally rectangular annular slots etched into the conductive layer on the substrate integrated waveguide 404; two PIN diodes operatively coupled to one of the generally rectangular annular slots; and two additional PIN diodes operatively coupled to the other generally rectangular annular slot. The PIN diodes operatively coupled to the corresponding rectangular annular slots help control the selective operation of the slots in a radiating state (radiating electromagnetic waves) and a non-radiating state (not radiating electromagnetic waves).

[0136] Two rectangular annular slots of the same subwavelength unit are substantially identical in shape and size, but oriented differently. Specifically, one slot extends substantially along one axis, and the other slot extends substantially along another axis. The two axes are aligned at approximately 90 degrees. The two rectangular annular slots can radiate electromagnetic waves with orthogonal characteristic polarization states (each slot can radiate electromagnetic waves with its own characteristic polarization state). For each of the two rectangular annular slots, two corresponding PIN diodes are connected across two opposite slot portions on opposite long sides of the respective slot. In this example, the two PIN diodes of one rectangular annular slot are arranged substantially along a first axis (generally perpendicular to the extension axis of the corresponding slot), while the two PIN diodes of the other rectangular annular slot are arranged substantially along a second axis (generally perpendicular to the extension axis of the corresponding slot). The first and second axes are substantially perpendicular.

[0137] PIN diodes can be controlled by control signals (such as a spatiotemporally encoded sequence of "0" and "1") provided by a controller (such as a field-programmable gate array, not shown in the figure). Specifically, in this embodiment, each PIN diode can selectively operate in an on and off state to affect the operation of the corresponding slot to which it is operably coupled. Two PIN diodes in the same slot can be controlled by the same control signal, or otherwise arranged to operate simultaneously in an on or off state, thereby selectively operating the corresponding slot in a radiating or non-radiating state. PIN diodes in the same slot can be biased to the same bias state (forward bias, no bias, etc.) by a bias circuit (or a portion thereof). In this embodiment, the bias circuit is formed or arranged in the lower conductive layer of the substrate integrated waveguide 404.

[0138] The following description further details various aspects or example operations of the metasurface antenna 400. The metasurface antenna 400 used herein may be referred to as a general-purpose metasurface antenna 400.

[0139] The figures will be referenced in a different order than the order in which they appear. Therefore, for ease of explanation, a brief description of each figure will be provided before further explanation.

[0140] Figures 4A to 9 Overall, this involves a general-purpose metasurface antenna 400 for independently controlling all fundamental electromagnetic wave characteristics. Specifically, Figure 4A The Universal Metasurface Antenna 400 is shown. In short, as... Figure 4A As shown, slotted superatoms are arranged on top of the substrate-integrated waveguide 404 to convert guided waves into propagating waves with software-defined characteristics. A 1-bit "0 / 1" spatiotemporal coding sequence is used to switch the superatoms between radiative ("1") and non-radiative ("0") states, thereby controlling the fundamental properties of the radiated wave. In this example, only the momentum of the target harmonic frequency (m = +1 harmonic in this case) matches the momentum of free space; other unwanted higher-order harmonics are suppressed in both the waveguide and free space without phase matching. Figure 4B The configuration of the anisotropic superatom is shown, which includes two annular slots tilted at ±45°, each slot containing a pair of PIN diodes. Figure 5 The measured frequency shift is shown at different modulation frequencies. Figure 5 The illustration shows the measured spectrum in dB at a modulation frequency of 1.8 MHz. Figures 6 to 9 This demonstrates the control of electromagnetic wave characteristics by the Universal Metasurface Antenna 400. Specifically, Figure 6 Momentum control is involved. Figure 7 Involves phase control, Figure 8 Involves amplitude control, Figure 9Polarization control is involved. In these examples, control is achieved by adjusting or tuning the time gradient, respectively. Reference time offset t i＝1 This is achieved by the duty cycle τ, the time gradient of polarization |u>, |v>, and the reference time offset. Figures 6 to 9 In the example, the input frequency and modulation frequency are f0 = 23.5 GHz and f... M =1.8MHz.

[0141] Figure 10 This relates to the general-purpose metasurface antenna 400, which is used to simultaneously manipulate various characteristics of radiated electromagnetic waves. Figure 10 It contains 9 images in 3 rows and 3 columns. Specifically, Figure 10 Figures a through c in the first row show the measurement results of the far-field radiation mode of the general metasurface antenna at the fundamental frequency and polarization |x>, with the main beam scanned to -40°, 0° and 40°, respectively. Figure 10 Figures d to f in the second row show the far-field radiation mode measurement results of the general metasurface antenna under fundamental frequency and polarization |u> conditions, with its main beam scanned to -40°, 0° and 40° respectively. Figure 10 Figures g to i in the second row show the far-field radiation mode measurements of the general metasurface antenna when the extracted propagation wave frequency becomes the +1 harmonic, with polarization |u>. The main beam is scanned to -40°, 0°, and 40°, respectively. The three lines in each figure represent the amplitude control of the radiated propagation wave. In this example, the input frequency and modulation frequency are f0 = 23.5 GHz and f... M =1.2MHz.

[0142] Figures 11 to 17 Related to the Universal Metasurface Antenna 400, this antenna utilizes spatially varying wave characteristics for more complex beamforming. Specifically, Figure 11 A general-purpose metasurface antenna 400 is shown for generating an Airy beam at the m=-1 harmonic frequency in free space. In this example, the Airy beam requires a spatially varying phase profile. like Figure 12 As shown. Figure 12 The aperture phase profile required to display the Airy wavefront, and the corresponding normalized time offset of the 400 metaatoms at different locations. Figure 13 The electric field intensity measured on the xz plane at different harmonic frequencies is shown. Figure 13 In the diagram, the dashed line represents the theoretical parabolic trajectory of the Airy beam, x = az. 2 (In this example, the acceleration factor a = 0.003). Only the target harmonic frequency m = -1 has a high field strength; other harmonic frequencies are highly suppressed in free space. Figure 14A general-purpose metasurface antenna 400 is shown, arranged to focus light at the m = -1 harmonic frequency. In this example, the local momentum or output angle of the propagating wave extracted from all the metaatoms of the metasurface antenna 400 is different. Figure 15 This shows the normalized local momentum k required for different focal spot locations from F1 to F5. x / ξ m Functional relationships with superatomic positions, where F1 = (-100mm, 80mm), F2 = (-70mm, 80mm), F3 = (-40mm, 80mm), F4 = (-10mm, 80mm) and F5 = (20mm, 80mm). Figure 16 The electric field strength measurements at the harmonic frequencies are displayed as the focal spot scans from F1 to F5. Figure 17 The corresponding electric field strengths measured on the xz plane at different focal spots F1 to F5 at harmonic frequencies are shown.

[0143] Figures 18 to 22 This relates to the general-purpose metasurface antenna 400, which is used for information modulation with time-varying wave characteristics. Specifically, Figure 18 A general-purpose metasurface antenna 400 for directly generating information-carrying electromagnetic waves in free space is shown. Figure 18 The diagram also shows the decoded constellation diagrams and eye diagrams at the receiver, measured at the m=+1 harmonic frequency, for QPSK (left) and 16QAM (right) fundamental frequency, as well as the one-to-one mapping between the transmitted digital information stream, the radiated information carrier in free space (2PSK in this example), and the animated STC matrix (STC film) used for communication at the m=+1 harmonic frequency. Other modulation schemes and the STC films required for the fundamental frequency are shown in [link to documentation]. Figure 34 and Figure 35 . Figure 19 A general-purpose metasurface antenna 400 is demonstrated for directly generating two independent modulated waves carrying different digital data streams. Two designated users located at different locations can simultaneously and independently receive information from the general-purpose metasurface antenna. In this example, the STC film required for multi-channel operation is as follows: Figure 37 As shown. Figure 20 The measured radiation modes of the general metasurface antenna 400 at harmonic frequencies of m = -1 (CH1) and m = -2 (CH2) are shown. Figure 20 The inset on the right shows the decoded constellation diagram of the two channels as measured at the receiver. More results on multiplexing in different beam directions can be found... Figure 38 and Figure 39 . Figure 21 A general-purpose metasurface antenna 400 with inherent directional modulation characteristics at the fundamental frequency is demonstrated. In this example, only the target user in the direction of the main beam can successfully decode the information, while eavesdroppers in other locations will completely lose the information. Figure 21The measured radiation patterns of the general metasurface antenna are shown, as well as the measured decoded constellation diagrams when the receiver is located in different directions. Figures 44 to 47 The physical layer secure communication links in other main beam directions were verified. Figures 18 to 22 In this context, "CW" stands for continuous wave; "Dig.Info" refers to digital information; "Mod" refers to modulation; "Ant." refers to antenna; "VSA" refers to vector signal analyzer; "CH" refers to channel; and "EVM" refers to error vector amplitude.

[0144] Figures 23 to 26 This relates to a general-purpose metasurface antenna 400, which is used for frequency-shifted wave operation. Specifically, Figure 23 The configuration of a general-purpose metasurface antenna 400 is shown, with its superatom array located on top of a waveguide. In this embodiment, each superatom includes two ±45° tilted slots for radiating two orthogonal characteristic polarizations and states. Each slot is embedded with a PIN diode controlled by an external FPGA control signal to switch the superatom between radiating (coded element "1") and non-radiating (coded element "0") states in real time. Figure 24 The diagram shows the form of a "0 / 1" STC matrix, representing the radiative / non-radiative states of all superatoms within a modulation period. Each slot opening has its own independent time-coded sequence. The STC matrix consists of two parts: the upper and lower parts correspond to the slot opening and polarized radiation, respectively. Figure 25 The time series of each superatom is shown, with a time offset of t. i . Figure 26 The working principle of a general-purpose metasurface antenna 400 for harmonic frequency wavefront manipulation is shown. The extracted total phase shift of the wave consists of two parts: the guided wave... Phase accumulation and time-space control caused by propagation The resulting abrupt phase shift. Time shifts applied to superatoms can control the momentum and phase of target harmonic frequencies.

[0145] Figure 27 A general-purpose metasurface antenna 400 for frequency shifting is shown. Specifically, Figure 27 This demonstrates how a universal metasurface antenna 400 upconverts the input frequency f0 to f0+f in free space. M In this example, the input frequency and modulation frequency are f0 = 23.5 GHz and f... M =1.2MHz. Figure 27 The measured input and residual spectra of the waveguide, as well as the output spectrum in free space, are also shown. In this example, due to the significant momentum mismatch between the waveguide and free space, the harmonic frequencies in the waveguide and free space are 25 dB and 21 dB lower than the fundamental frequency, respectively. Due to the waveguide-to-propagation conversion of the metasurface antenna, the residual power of the waveguide at the fundamental frequency is 14.7 dB lower than the input power.

[0146] Figures 28 to 33 A general-purpose metasurface antenna 400 was demonstrated, which can perform wave operation without frequency shifting. Specifically, Figure 28 This illustrates the conversion or translation of a guided wave to a propagating wave at the fundamental frequency (m=0). In this example, the time-controlled mechanism forms an equivalent sinusoidal amplitude envelope along the metasurface aperture length of the metasurface antenna 400. The n=-1 spatial harmonic is a fast wave and radiates into free space with software-defined arbitrary wave characteristics. Figure 29 The randomization of the STC matrix is ​​shown to suppress higher-order harmonic frequencies. Figures 30 to 33 This demonstrates the independent electromagnetic wave characteristics manipulated at the fundamental frequency. Specifically, Figure 30 Related to polarization control, Figure 31 Related to momentum control. Figure 32 Related to phase control, Figure 33 This relates to amplitude control. In these examples, control is achieved by adjusting the equivalent spatial period Λ, the spatial offset Δx of the amplitude envelope, the modulation depth M, and the spatial period and spatial offset of the polarizations |u> and |v>, respectively.

[0147] Figure 34 and 35 This relates to the general-purpose metasurface antenna 400, which is used for information processing with time-varying wave characteristics. Specifically, Figure 34 This demonstrates the one-to-one correspondence between the QPSK symbol set, the transmitted signal set, and the STC matrix set (in this example, the radiation of the m=+1 harmonic frequency) in the constellation diagram. Figure 35 The digital baseband signal, the corresponding modulation free space waveform, and the STC film (in this example, the baseband frequency) required for different modulation formats (including 2ASK, 2PSK, and 16QAM) are shown.

[0148] Figures 36 to 39 This relates to a general-purpose metasurface antenna 400 for multi-channel wireless communication. Specifically, Figure 36 This demonstrates a shared aperture technique for transmitting two independent modulated waves using a universal metasurface antenna, where each sub-metasurface is responsible for generating one modulated waveform. Figure 37 This paper demonstrates the synthesis process of STC films for dual-channel wireless communication. In short, in this example, the bitstream of each sub-metallic surface is first mapped onto the corresponding STC film according to the desired switched harmonic frequency, polarization, and signal modulation format. The final STC film for dual-channel multiplexing is the sum of the two STC films for the two interleaved sub-metallic surfaces. Figure 38 and 39 The measured radiation modes of the universal metasurface antenna at harmonic frequencies of m = -1 (CH1) and m = -2 (CH2) are demonstrated. Figure 38 and 39In the middle, the main beam directions of CH1 and CH2 point to (0°, 30°) and (30°, -30°) respectively. Figure 38 and 39 The illustration on the right shows the decoded constellation diagram of the two channels as measured by the receiver.

[0149] Figures 40 to 43 This relates to the 400 general-purpose metasurface antenna that employs BPSK scheme-based directional modulation. Specifically, Figure 40 This concept explains how the fundamental frequency time-of-use (BFSU) mode imparts two equivalent sinusoidal amplitude envelopes to generate two highly directional beams with a 180° phase difference along the wide side of the BPSK scheme. The spatial offset of the two equivalent sinusoidal amplitude envelopes is Δx = Λ / 2. Figure 40 The illustration shows the STC matrix required to generate this spatial amplitude envelope at the fundamental frequency. Figure 41 The relationship between the phase difference between two radiation cases and the observation direction θ is shown. Figure 42 This conceptually illustrates a universal metasurface antenna 400 for directly generating BPSK modulated waves at the baseband frequency. In this example, only the target user located in the direction of the main beam will receive the correct phase change (information), while an eavesdropper located at an angle will decode a garbled constellation. Figure 43 The theoretical power modes of the universal metasurface antenna and the EVM are shown as a function of the observation direction.

[0150] Figures 44 to 47 Further results regarding the use of the Universal Metasurface Antenna 400 for physical layer secure communication are presented. Specifically, Figure 44 and 45 The measurement radiation modes and measurement decoding constellation diagrams of the universal metasurface antenna 400 are shown when the receiver is located in different directions. The main beam direction of the universal metasurface antenna 400 is scanned to 30° respectively. Figure 44 ) and -30° Figure 45 As shown in the figure, only receivers in the main beam direction can successfully decode information from the general-purpose metasurface antenna 400. Figure 46 This concept illustrates a conventional beam-scanning transmission system in which free-space radiation carries the same time-varying wave characteristics (information) in all directions. Figure 47 The measured radiation modes of a general-purpose metasurface antenna 400 operating at the m=-1 harmonic frequency are shown, along with the measurement decoding constellation diagrams when the receiver is positioned in different directions. In this example, the receiver successfully decodes information outside the main beam.

[0151] Figures 48A to 49 The setup used to identify the Universal Metasurface Antenna 400 prototype was demonstrated. Specifically, Figure 48A and 48BA schematic diagram and photograph of the measurement apparatus used to measure the radiation modes of the metasurface antenna 400 prototype are shown. Figure 49 A dual-channel wireless communication link test platform is shown, in which a general-purpose metasurface antenna can directly and simultaneously generate two independent modulated waves with different information. Two horn antennas connected to two vector signal analyzers (VSAs) are used for receiving and demodulating the signals. Figures 48A to 49 In this context, "DUT" stands for Device Under Test; "VNA" stands for Vector Network Analyzer; and "Rx" stands for Receiver.

[0152] Figure 50 The theoretical and experimental far-field radiation modes of the m=+1 harmonic frequency radiation of the Universal Metasurface Antenna 400 are shown.

[0153] Figure 51 and 52 The STC matrix for achieving polarization control in the metasurface antenna 400 is shown. Specifically, Figure 51 The “0 / 1” STC matrix required for polarization control at the m = +1 harmonic frequency is shown. Figure 52 Display the “0 / 1” STC matrix required for m=0 fundamental frequency polarization control for different polarizations (including |x>, |y>, |u>, |v>, |LCP>, and |RCP>).

[0154] Figure 53 Theoretical and measured components of six representative polarizations (including |x>, |y>, |u>, |v>, |LCP>, and |RCP>) obtained using a metasurface antenna 400 are shown.

[0155] After a brief overview of the accompanying drawings, further details regarding various aspects or example operations of the metasurface antenna 400 are now provided.

[0156] Operation of basic electromagnetic wave characteristics

[0157] The general-purpose metasurface antenna 400 in this embodiment can independently control some or all of the basic electromagnetic wave characteristics (amplitude, phase, polarization, frequency, and momentum).

[0158] Regarding frequency control, the inventors of this invention recognized that frequency control is generally challenging because it requires changing the energy of photons, and existing frequency control methods based on nonlinear bulk media suffer from weak nonlinear effects and strict phase-matching conditions (PMC). In this regard, the universal metasurface antenna 400 includes multiple space-time coded (STC) metaatoms to facilitate (i) time modulation of the nonlinear effects and (ii) time-space modulation of the newly generated wave to free space, thereby mitigating PMC. Figure 4ASpecifically, the periodic switching of the superatomic radiation state can provide an infinite number of harmonic frequencies f0+mf. M , where m is an integer. In one example, the same time series with a position-dependent time offset is applied to the superatom ( Figure 25 According to the time-shifting properties of the Fourier transform, the shift in the time domain corresponds to a linear phase shift of -2πmf in the frequency domain. M t i Therefore, the total phase shift of the radiated propagating wave (PW) consists of two parts ( Figure 26 (i) Phase accumulation during guided wave (GW) propagation (here ξ) GW Sudden phase shift caused by air conditioning when the wave number in the waveguide is (ξi) and ξi is (ξi) The corresponding linear momentum of the radiated propagating wave along the x-direction is k. x (f0+mf M )=ξ GW +k ST ,,in This is the additional momentum imparted by the air conditioning system. In one example ( Figure 4A This momentum is used to compensate for the momentum mismatch between the waveguide and free space at the target m = +1 harmonic frequency, i.e., -ξ. m＝+1 <ξ GW +k ST <ξ m＝+1 , where ξ m＝+1 It is the free-space wavenumber at the m=+1 harmonic frequency. Due to the significant momentum mismatch, other unwanted harmonics are not supported and suppressed in free space and waveguides. Figure 27 In this way, the Universal Metasurface Antenna 400 can simultaneously achieve near-perfect waveguide-to-propagation conversion and frequency shifting. Figure 5 This shows how to change the modulation frequency f M The spectrum of the propagating wave was measured at different frequency shift values ​​(from -1.8MHz to +1.8MHz, with a step size of 0.6MHz).

[0159] The general-purpose metasurface antenna 400 can also perform momentum control on electromagnetic waves. Assuming an applied time gradient... If θ is a constant, then the radiated propagating wave has a definite radiation angle θ. r =sin -1 (k x / ξ m Therefore, the momentum and corresponding output angle of the radiated propagating wave can be adjusted by changing the applied time gradient. Figure 6 ).

[0160] The general-purpose metasurface antenna 400 can also perform phase control on electromagnetic waves. Because... While maintaining a fixed time gradient, the initial phase of the extracted propagating wave can be adjusted from 0° to 360° by changing the reference time shift (the first superatomic phase shift). Figure 7 ).

[0161] The general-purpose metasurface antenna 400 can also perform amplitude control on electromagnetic waves. The power distribution of harmonic frequencies typically depends on the encoding of the time series. The amplitude of the extracted propagating wave can be adjusted by changing the duty cycle τ of the rectangular time series. Figure 8 ).

[0162] The general-purpose metasurface antenna 400 can also control the polarization of electromagnetic waves. In one example, the general-purpose metasurface antenna 400 can generate arbitrary polarization by applying independent STC matrices to the ±45° tilted slot openings to change the amplitude ratio and phase difference of the extracted U-polarization and V-polarization components. In one example, six representative polarizations (|x>, |y>, |u>, |v>, |LCP> (left-handed circular polarization) and |RCP> (right-handed circular polarization) are provided as examples of polarization controllability. Figure 9 ). Figure 51 and 52 The required STC matrix is ​​provided.

[0163] The general-purpose metasurface antenna 400 can also independently manipulate all characteristics of the radiated propagating wave without changing the frequency. In one example, by utilizing the time-averaging effect of the time-spaced modulation, an equivalent sinusoidal amplitude distribution is formed at the fundamental frequency. Figures 28 to 33 Thus, the n=-1 spatial harmonic becomes a fast wave. It is converted into a propagating wave, and its wave characteristics can be independently controlled by a 1-bit time-limited control. Figures 28 to 33 Further details on this topic will be provided below.

[0164] The universal metasurface antenna 400 can simultaneously control various characteristics of electromagnetic waves. To demonstrate this, we obtained the far-field radiation pattern of the universal metasurface antenna 400. Figure 10 Each figure presents three different amplitude radiation scenarios to demonstrate independent amplitude controllability. Figure 10 The graphs in the same row represent radiated waves with the same wave characteristics but different linear momentum, with corresponding beam angles ranging from -40°, 0° to +40°, verifying the synchronous control of amplitude and momentum. Polarization changes from |x> in the first row of graphs to |u> in the second row, thus allowing simultaneous control of amplitude, momentum, and polarization. The output frequency further changes from the fundamental frequency (m=0) in the second row of graphs to the m=+1 harmonic frequency in the third row of graphs (while all other wave characteristics remain unchanged). Therefore, this example verifies that the universal metasurface antenna 400 can simultaneously control amplitude, momentum, polarization, and frequency.

[0165] Electromagnetic wave manipulation and information modulation

[0166] The general-purpose metasurface antenna 400 can generate relatively complex structured light with spatially and temporally varying wave characteristics. In some examples, the metasurface antenna 400 can achieve arbitrary beam manipulation to generate Airy beams and light focusing. Figure 11 and 14 ).

[0167] In one example, the required spatial phase change for the Airy wavefront is (-x). 3 / 2 ( Figure 12 To generate the parabolic caustic x∝z 2 To achieve this spatially varying phase distribution at the m = -1 harmonic frequency, superatoms ( Figure 12 The space-dependent time offset was introduced in ). Figure 13 The electric field intensity distribution measured at different harmonic frequencies is shown. It can be seen that the universal metasurface antenna 400 can extract and shape radio waves into an accelerating, non-diffractive Airy beam with a well-defined parabolic trajectory. Furthermore, other unwanted harmonic frequencies are also highly suppressed in free space.

[0168] In one example, the metasurface antenna 400 can also shape the extracted wave into a shape with spatially varying momentum characteristics k. x (x) light focusing application ( Figure 14 In this example, the metasurface antenna directs the focus from F1 to F5 at the m = -1 harmonic frequency. Figures 15 to 17 The required spatial momentum and the one-dimensional and two-dimensional electric field intensity distributions measured under different focusing conditions at the m = -1 harmonic frequency are shown. It can be seen that the metasurface antenna 400 can extract and shape the propagating wave into a predetermined focus, the position of which can be defined by software according to the applied STC matrix.

[0169] These examples demonstrate the flexible and agile beamforming capabilities of the Universal Metasurface Antenna 400, which could be particularly useful in sensing, imaging, and wireless power transmission applications.

[0170] The general-purpose metasurface antenna 400 can realize or facilitate information manipulation by generating time-varying wave characteristics. Figure 18 By loading an animated STC matrix (also known as "STC film"), the universal metasurface antenna 400 can directly generate modulated waveforms with time-varying amplitude and phase characteristics and map them to the desired digital information stream. Figure 18 ). Figure 18The decoded constellation diagram and eye diagram of the receiver are also shown when information is transmitted at harmonic frequencies of m=+1 and m=0. The information manipulation capabilities of the general-purpose metasurface antenna 400 have been verified for different information modulation schemes, including phase shift keying (PSK) and quadrature amplitude modulation (QAM). Figure 34 and 35 These two approaches require time-varying phase and time-varying amplitude and phase characteristics, respectively. Existing transmitters typically rely on a heterodyne structure consisting of a series of active / passive RF modules (including digital-to-analog converters, modulators, mixers, filters, phase shifters, and antenna arrays) to generate this modulated wave in free space, shaping a propagating wave with time-varying amplitude and phase (information-carrying) characteristics. In contrast, the universal metasurface antenna 400, as a single component or device, can directly generate the same modulated wave in a single step. This provides a different communication mode at the physical layer, offering advantages such as simpler structure, higher integration, lower cost, and / or lower power consumption.

[0171] Furthermore, the Universal Metasurface Antenna 400's control over other electromagnetic wave characteristics (momentum, frequency, and polarization) provides more opportunities for realizing Space Division Multiplexing (SDM), Frequency Division Multiplexing (FDM), and Polarization Division Multiplexing (PDM), thereby enabling the establishment of multiple independent channels and increasing communication capacity.

[0172] We established an SDM-FDM-PDM combined data transmission link ( Figure 19 and Figure 49 The general-purpose metasurface antenna 400 can simultaneously transmit two independent channels with different beam directions (-30° and +30° for SDM), different polarizations (|u> and |v> for PDM), different frequencies (m=-1 and m=-2 harmonics for FDM), and different information modulation schemes (QPSK and 8PSK). To this end, a shared aperture method was developed to enable the general-purpose metasurface antenna 400 to achieve this complex wave and information operation. Figures 36 to 39 ). Measured far-field radiation patterns ( Figure 20 ) and the decoding constellation diagram on the receiver ( Figure 20 The illustration on the right verifies that the Universal Metasurface Antenna 400 can achieve simultaneous and independent multiplexing.

[0173] In traditional transmitter architectures, radiated electromagnetic waves from different directions possess the same time-varying wave characteristics (information). Therefore, eavesdroppers, by using sufficiently sensitive receivers, can even recover information in the sidelobe region. Figure 46 and 47 In one example, the universal metasurface antenna 400 can provide an inherently directional modulation (IDM) phenomenon at the fundamental frequency. This unique IDM characteristic is attributed to the direction-dependent phase control of the universal metasurface antenna 400. Figures 40 to 43 To verify this, a communication link was established through which the general-purpose metasurface antenna 400 directly transmitted a modulated wave of the baseband 8PSK signal. Figure 21 ). Figure 22 The diagram shows the measured radiation patterns and decoding constellation diagrams when the receiver is positioned in different directions. It can be seen that the receiver can only successfully decode information in the direction of the main beam of the universal metasurface antenna (information outside the main beam is completely lost). This IDM effect can be used to effectively mitigate malicious eavesdropping attacks from different directions, establishing physical layer security on top of wireless communication. IDM is an inherent characteristic of the universal metasurface antenna 400, requiring no optimization or performance trade-offs, and can typically achieve physically secure communication links through conventional methods.

[0174] Wave manipulation with frequency shift

[0175] In this example, the theoretical model of the waveguide-integrated metasurface antenna is extended to a more generalized model by considering polarization factors. In this example, the metasurface is represented or described by an array of subwavelength scatterers with discrete metasurface properties. The general-purpose metasurface antenna 400 includes a slot-based metaatom array etched along the x-axis on a conductive layer on top of the substrate-integrated waveguide. Figure 23 In this example, the anisotropic slotted superatom is equivalent to a magnetic dipole fed by two orthogonally oriented waveguides, which can extract energy from the waveguides and radiate it into free space. The wave characteristics of the extracted |u> and |v> components can be independently controlled by applying independent control voltages to the PIN diodes within the superatom. Figure 24 The i-th superatom is in x. i Excited polarization magnetic dipole moment with |u> and |v> components at position for

[0176]

[0177] Where is the magnetic polarization Jones matrix at instant t. H i This is the magnetic field of the reference guided wave within the waveguide. Because the radiation state of the superatom has a time period T... M It turns on and off periodically, therefore the magnetic polarization is a periodic function of time, satisfying... It can be decomposed into a Fourier series.

[0178]

[0179] Where f M =1 / T M The modulation frequency. Fourier coefficients. The calculation formula is:

[0180]

[0181] Substituting formula (2) into formula (1) yields the result.

[0182]

[0183] According to formula (4), it can be determined that the periodic ON-OFF switching of the superatom can generate an infinite number of harmonic frequencies with a frequency interval of f. M This nonlinear effect provides an opportunity to control the frequency characteristics of electromagnetic waves. Furthermore, time-spaced modulation introduces equivalent magnetic polarization at the m-th harmonic frequency. This provides additional degrees of freedom for controlling other properties of electromagnetic waves. Once the excitation magnetic polarization of each superatom is known, the radiation modes of the universal metasurface antenna 400 in free space can be obtained.

[0184] In one example, the same rectangular time series was applied to all superatoms. Figure 25 (Δt=0). The corresponding magnetic polarization can be expressed as:

[0185]

[0186] Wherein, P0 is the constant magnetic polarization of the superatom when it is in a radiative state. It is the duty cycle of |u> and |u> components, defined as the ratio of the time the superatom is in the coupled state (“1”) to the modulation time period. Substituting formula (5) into formula (3), the equivalent magnetic polarization of the i-th superatom at the m-th harmonic frequency is... for

[0187]

[0188] As can be seen from equation (6), the magnetic polarization amplitude of each harmonic is the duty cycle used. The function. To further achieve phase control, the superatom introduces a time delay. ( Figure 25 Equivalent magnetic polarization Become

[0189]

[0190] Comparing equations (6) and (7), an additional phase term is introduced into the equivalent magnetic polarization at the m-th harmonic frequency. This phase term depends on the applied time delay. Figure 26 In this way, the amplitude and phase of the excited magnetic polarization can be decoupled and controlled independently.

[0191] Arbitrary polarization can be decomposed into a linear combination of two perfectly orthogonal polarization bases (such as and ), and vice versa. In this example, the anisotropic superatom comprises a pair of ±45° tilted elliptical slots with a large aspect ratio, and the associated radiative electric field polarization is perpendicular to the longer side ( Figure 23 By applying independent STC matrices to the ±45° tilted slots in each cell, the amplitude and phase content of the extracted |u> and |v> components can be independently controlled, thus enabling the universal metasurface antenna 400 to produce arbitrary polarization. Specifically, the ±45° tilted slot openings adopt the same time gradient. This ensures that the |u> and |v> components have the same momentum and output direction. Different initial time delays and duty cycles can be used for ±45° tilted slots to control the amplitude ratio and phase difference of the radiated |u> and |v> components respectively. The general-purpose metasurface antenna 400 is equipped with different STC matrices (…). Figure 51 This produces six representative polarizations, including |x>, |y>, |u>, |v>, |LCP>, and |RCP>. Figure 9 ).

[0192] For completeness, the theoretical radiation modes of the general metasurface antenna 400 will be described in further detail.

[0193] In one example, the discrete dipole method is used to calculate the far-field radiation modes of the universal metasurface antenna 400. In this example, the magnetic dipole moment is used as a weighting factor in the array factor calculation. In this example, each metaatom can be considered as two magnetic dipoles tilted at ±45°, and its far-field radiation can be expressed as...

[0194]

[0195] Where θ is the observation direction relative to the metasurface normal. The superatom mode is simulated as a cosine function cosθ. Substituting equations (4) and (7) into (S1), the following results are obtained:

[0196]

[0197] By superimposing the radiation fields of all the superatoms, the far-field radiation mode of the Universal Metasurface Antenna 400 can be obtained.

[0198]

[0199]

[0200] Assuming time gradient It is a constant, and formula (S3) can be further expressed as

[0201]

[0202] The beam radiation direction (output angle) of the propagating wave is the direction in which the extracted waves of all superatoms undergo constructive interference:

[0203]

[0204] Only when the momentum matching condition is met Only when the desired momentum is met can the extracted propagating wave form a collimated beam in free space. This is due to different momentum values. Different harmonic frequencies will be introduced, so a spatiotemporal sequence can be designed such that only the harmonic frequencies of interest satisfy the momentum matching condition in free space. In one example, the beam directions of other unwanted harmonics are not in the visible light region, so these harmonics will not radiate into free space. Figure 50 The theoretical and measured far-field radiation modes for a universal metasurface used for m = +1 harmonic radiation are shown. The theoretical and measured far-field radiation modes are similar. This verifies the effectiveness of the developed method for calculating far-field radiation modes.

[0205] For completeness, further derivation details of formula (6) are also provided.

[0206] The equivalent magnetic polarization of the i-th superatom at the m-th harmonic frequency in formula (6) The derivation is as follows:

[0207]

[0208] Wave manipulation without frequency shift

[0209] For wave manipulation at the fundamental frequency (m=0), the equivalent magnetic polarization caused by time-controlled operation in equation (3) can be simplified to:

[0210]

[0211] It can be determined that the equivalent magnetic polarization at the fundamental frequency is the time-averaged magnetic polarization of one modulation period. Specifically, when using a general rectangular time series, the equivalent magnetic polarization at the fundamental frequency in formula (7) can be simplified to: Time-space modulation can generate an equivalent amplitude of magnetic polarization without introducing phase shift or fundamental momentum. In one example, to facilitate the conversion of the fundamental guided wave to a propagating wave, sinusoidal amplitude modulation is generated along the waveguide length using the equivalent magnetic polarization, causing the n=-1 space harmonic to become rapid and radiate into free space. Figure 28 ).

[0212]

[0213] In the formula, is the modulation depth of the |u> and |v> components. Λ is the spatial period of the sinusoidal amplitude envelope. The radiation of the equivalent magnetic dipole can be regarded as spatial sampling of the reference guided wave at each superatomic position.

[0214] In one example, the momentum of the n = -1 spatial harmonic along the x-direction is k. x =ξ gw -2π / Λ, which matches the momentum of free space, provided that -1 < k x / ξ0<1. The corresponding output angle of the spatial harmonic of n=-1 is Furthermore, in order to suppress higher harmonic frequencies, while maintaining the equivalent sinusoidal modulation of the superatoms, the applied time delay and time series were randomized. Figure 29 Because the momentum of higher harmonic frequencies is inconsistent with that of free space and the waveguide, undesirable higher harmonic frequencies (m≠0) are significantly suppressed. This is achieved by changing the applied STC matrix ( Figure 31 The spatial period can be changed, thereby adjusting the momentum and corresponding output angle of the extracted propagating wave. The spatial shift characteristic of the Fourier transform can be used to control the phase of the extracted propagating wave. Similar to the time shift characteristic, but in the spatial domain, a spatial shift Δx can lead to a phase shift of 2πnΔx / Λ in the nth-order spatial harmonic. In one example, applying different spatial displacements Δx to the sinusoidal amplitude envelope will result in different phases in the radiated n=-1 spatial harmonic. Figure 32 In one example, the power extracted by each superatom from the waveguide is modulated with a sinusoidal amplitude. The modulation efficiency is directly proportional to the modulation depth M. Therefore, the amplitude of the propagating wave extracted by the universal metasurface antenna can be adjusted. Figure 33 In one example, the general-purpose metasurface antenna 400 can generate arbitrary polarization by controlling the amplitude ratio and phase difference of the extracted wave and components. For this purpose, an equivalent sinusoidal amplitude distribution with the same spatial period can be applied to a ±45° tilted slot, thus ensuring that the extracted components have the same output angle in free space. Applying different spatial translations and modulation depths to the ±45° tilted slot allows control of the amplitude ratio and phase difference of the components, respectively. For example, the general-purpose metasurface antenna 400 can be loaded with different STC matrices (…). Figure 52 This yields six representative polarizations: |x>, |y>, |u>, |v>, |LCP>, and |RCP>. Figure 30 ).

[0215] Airy Beam Generation

[0216] For the generation of collimated propagating waves, the waves extracted from all metaatoms radiate at the same output angle, thus exhibiting asymptotic phase distribution along the x-direction. In one example, the metasurface antenna 400 can generate electromagnetic waves with more complex spatially varying phase characteristics for producing Airy beams. The desired phase profile of the metasurface antenna 400 along the line should conform to the following equation to produce a parabolic trajectory under ray optics and quasi-axis approximation conditions:

[0217]

[0218] Where a is the acceleration factor, ξ m This is the free-space wavenumber of the target m-th harmonic frequency. The corresponding theoretical trajectory is a parabolic wake with the value x = az. 2 For the general-purpose metasurface antenna 400, the phase distribution of the extracted wave at the m-th harmonic frequency is the sum of the guided wave cumulative phase shift and the equivalent phase shift imparted by the time-spaced mechanism, expressed as: ( Figure 26 Combining formula (10), the normalized time shift required for the universal metasurface antenna 400 is given by the following formula.

[0219]

[0220] For example, Figure 12 The time-shift results for generating an Airy beam with an acceleration factor a = 0.003 at a harmonic frequency of m = -1 are shown.

[0221] Light Focusing

[0222] In one example, the universal metasurface antenna 400 can extract and convert light into the desired focal point F = (x) in free space. F , z F ()( Figure 14 Based on geometric relationships and geometric rays, the extracted linear momentum of the propagating wave should satisfy...

[0223]

[0224] To achieve the linear momentum of the extracted propagating wave, the required time gradient is:

[0225]

[0226] In one example, the universal metasurface antenna 400 is considered to produce different predetermined focal points from F1 to F5 at the m = -1 harmonic frequency (the required spatial variation linear momentum is as follows). Figure 15 (As shown). The corresponding one-dimensional and two-dimensional field strength distributions at the m=-1 harmonic frequency are shown in the figure. Figure 16 and 17 .

[0227] Shared-aperture metasurface for multi-channel communication

[0228] In one example, the universal metasurface antenna 400 can be divided into two interwoven sub-metasurfaces ( Figure 36 Each sub-metasurface is fitted with an independent STC film, which generates a specific modulation waveform corresponding to a communication channel. In one example, the superatomic lattice of the sub-metallic surface is 0.31λ0 (λ0 is the free-space wavelength at 23.5 GHz). The sub-metasurfaces exhibit no higher-order diffraction in free space. Figure 21 The resulting universal metasurface antenna 400 can be viewed as a combination of two interwoven sub-metasurfaces sharing a single radiation aperture above the waveguide to produce two independent modulation channels. In one example, two distinct time gradients are applied to the two sub-metallic surfaces, and the equivalent momentum imparted by the time-varying mechanism propels the m = -1 and m = -2 harmonic frequencies into free space, with output angles of -30° and 30° for the two sub-metallic surfaces, respectively. The amplitude and phase contents (carried information) of the two extracted propagating waves can be independently controlled by applying duty cycles and reference time shifts according to the transmitted binary bit streams of the two channels. The polarization states of the two radiated beams can be controlled by applying different spatiotemporal coding sequences to the ±45° tilted slots of each sub-metallic surface.

[0229] Figure 37 An example of the STC film synthesis process supporting a dual-channel SDM-FDM-PDM data transmission link is shown. In this example, the bitstream of each sub-metal plane is mapped onto the corresponding STC film according to the desired conversion harmonic frequency, polarization, and signal modulation format. The final STC film of the dual-channel multiplexed circuit is the sum of the two STC films of the two interlaced sub-metal planes. Following the same shared aperture technique, the radiation directions of CH1 and CH2 can be further adjusted to (0°, 30°) and (30°, -30°), respectively. This can be achieved by changing the time gradient applied to the two sub-metal planes, thereby altering the momentum characteristics of the extracted propagating wave. Measured radiation modes ( Figure 38 and Figure 39 Decoding constellation diagram of the two channels at the receiving end and the receiving end () Figure 38 and Figure 39 The right-hand illustration verifies the SDM-FDM-PDM data transmission link. This demonstrates that shared aperture technology can integrate the functions of multiple sub-metasurfaces into a single aperture, thereby expanding the wave and information processing capabilities of the universal metasurface antenna 400.

[0230] Inherent directional modulation

[0231] The direction-dependent phase characteristics at the fundamental frequency can be explained from the perspective of spatial Fourier transform. The aperture field distribution of the metasurface and its spatial spectrum (far-field radiation mode in free space) F(θ) conform to the Fourier transform relation. Where A(x) is the equivalent spatial amplitude envelope transmitted by the time-space mechanism in equation (9). In one example, the spatial amplitude envelope introduces a spatial translation Δx( Figure 40 The aperture field distribution becomes... The relevant far-field radiation mode is

[0232]

[0233] As can be seen from equation (14), the spatial translation Δx of the amplitude envelope introduces an additional phase shift Δφ(θ) = -(ξ) for the phase mode. gw -ξ0sinθ)Δx, without affecting the power mode of the general metasurface antenna. Furthermore, the introduced phase shift Δφ is a function of the observation direction; that is, with a fixed spatial translation Δx of the amplitude envelope, different directions will have different phase shifts. In a special case (as a special case), when the main beam direction is... At that time, the main beam direction θ r The phase shift is

[0234] For ease of explanation, the BPSK modulation scheme will be used as an example to demonstrate the directional information modulation of the general metasurface antenna 400. Figure 40 This example shows two equivalent sinusoidal amplitude envelopes, arranged to produce highly directional beams with the same amplitude and a 180° phase difference in the 0-degree direction, mapped to digital information "0" and "1" respectively. For this purpose, the two equivalent sinusoidal amplitude envelopes share the same spatial period ∧, but with a spatial offset Δx = Λ / 2. According to formula (12), Figure 41 The figure shows the phase difference as a function of the observation direction θ for two radiation scenarios. It can be seen from the figure that an ideal 180° phase difference is produced in the main beam direction (wide side in this example), while a significant deviation occurs when deviating from the wide side direction. To directly generate the BPSK modulated waveform, an animated STC matrix (STC film) is applied to the general-purpose metasurface antenna 400 according to the required transmission "0 / 1" digital stream. Figure 42 ). Figure 43The theoretical radiated power pattern of the universal metasurface antenna is further shown (see also the related derivation under "Wave Manipulation with Frequency Shift") and the error vector magnitude (EVM) calculated in different observation directions in a noise-free environment. It can be seen that the power received by the eavesdropper in non-main beam directions is much weaker. Furthermore, unlike the target user (receiver), an eavesdropper at an off-angle will perceive incorrect phase changes (information) in the main beam direction, resulting in a corrupted constellation diagram. It is envisioned that the inherent directional modulation characteristics of the universal metasurface antenna 400 can also be applied to other higher-order modulation formats, such as 8PSK and QAM.

[0235] For completeness, further details of the derivation of equation (14) are also provided.

[0236] The aperture field distribution E(x) and its spatial spectrum (i.e., the far-field radiation mode in free space) F(θ) are a pair of Fourier transforms.

[0237]

[0238] Where A(x) is the equivalent sinusoidal amplitude envelope assigned by the fundamental frequency time-space regulation. Based on the spatial shift characteristics of the Fourier transform (similar to time shift characteristics, but in the spatial domain), the following results can be obtained:

[0239]

[0240] Then, spatial motion is introduced into the spatial amplitude envelope. The aperture field of the metasurface antenna becomes... Please note that spatial shifts in the amplitude envelope do not affect the propagation of the guided wave. The phase. Combining with formula (S8), then

[0241]

[0242] As can be seen from formula (S9), the spatial translation Δx of the amplitude envelope will bring a direction-dependent phase shift Δφ(θ) to the radiation mode. gw -ξ0sinθ)Δx.

[0243] prototype

[0244] Figure 4BThe configuration of the anisotropic superatoms of the metasurface antenna 400 is shown. In this example, for ease of integration with other components, a waveguide is integrated into the substrate as a waveguide structure, which uses multiple rows of parallel metal vias and a thin dielectric substrate to achieve a generally rectangular and planar waveguide. Two elliptical slots with ±45° inclination are etched on the top metal surface of the substrate-integrated waveguide. The cell size along the x-direction is 2 mm, equivalent to 0.158λ0. Each slot is a linearly polarized magnetic dipole whose extracted electric field polarization is perpendicular to the long side of the slot. By adjusting the geometry of the slots, the slot superatoms can be designed in a non-resonant state. Four PIN diodes (MACOMMADP-000907-14020x) span the slot capacitance gap of each superatom. A DC bias circuit is integrated into the cell design. This circuit includes a fan-shaped bias line (for RF choke) on the bottom bias circuit and control vias connecting the top superatom to the bottom bias circuit. In this example, via gates in the substrate-integrated waveguide are used as control vias to mitigate the perturbation of the bias network on the guided wave. Two PIN diodes in the same slot are biased in the same state, while PIN diodes in slots with different tilts are biased and controlled independently. In one example, the general-purpose metasurface antenna 400 includes 41 superatoms and 164 PIN diodes. In this example, an FPGA control board (ALTERA Cyclone IV) is operationally coupled to the general-purpose metasurface antenna 400 to control its operation. The FPGA control board generates 82 independent control signals (two independent control signals for each anisotropic superatom) to control the on-off state of the PIN diodes and the radiation state of the superatoms.

[0245] The radiation characteristics of the superatoms were modeled and simulated using the ANSYS HFSS numerical simulator based on the finite element method. Under forward bias (state "0"), the PIN diodes were simulated as a series connection of a resistor R = 8 Ω and an inductor L = 30 pH; under unbiased bias (state "1"), the PIN diodes were simulated as a series connection of a capacitor C = 0.052 pF and an inductor L = 30 pH. A waveport was used to excite the fundamental frequency TE of the substrate-integrated waveguide. 10 model.

[0246] For example, a general-purpose metasurface antenna 400 was fabricated using commercial multilayer printed circuit board (PCB) technology. Two Rogers 5880 substrates, with thicknesses of 1.575 mm and 0.787 mm respectively, were used for substrate-integrated waveguides and bias circuitry, bonded together with Rogers 4450F thin film. A total of 164 PIN diodes were then mounted in the gaps of the slots via reflow soldering. The radiation mode of the general-purpose metasurface antenna was measured in a microwave anechoic chamber using a reconfigurable robotic arm measurement system. Figure 48A and 48BIn one example, a signal generator (Agilent E8267D) emits a 23.5 GHz monochromatic wave to feed a universal metasurface antenna; a horn antenna is connected to a vector network analyzer (VNA, Keysight N9041B) to detect the electromagnetic waves radiated from the metasurface. A robotic arm grips the linearly polarized horn antenna, which can rotate from -90° to 90° along a user-defined circular path to measure the radiation modes of the universal metasurface antenna 400. By physically rotating the linearly polarized horn antenna, different polarization components of the electromagnetic wave can be measured.

[0247] To illustrate the information operation of a general-purpose metasurface antenna, an indoor wireless communication experiment was conducted. Figure 49 In this example, a microwave signal generator (Agilent E8267D) is used at the transmitting end to generate a monochromatic wave at a frequency of 23.5 GHz, which serves as the feed for the general-purpose metasurface antenna 400. The general-purpose metasurface antenna 400 directly generates and transmits a modulated wave with time-varying amplitude and phase characteristics (information) into free space. Random binary bit streams with different modulation formats (QPSK, 8PSK, and 16QAM) are generated and mapped to the corresponding STC film in the FPGA. At the receiving end, a linearly polarized pyramidal horn antenna connected to a vector signal analyzer (VSA, Keysight N9041B) is used to receive and demodulate the propagating wave from the general-purpose metasurface antenna 400. The vector signal analyzer recovers the received digital information and provides real-time constellation diagrams, eye diagrams, signal-to-noise ratio (SNR), and EVM performance. In this example, the distance between the general-purpose metasurface antenna and the receiving horn antenna is approximately 1.2 meters, the modulation frequency is set to 0.5 MHz, and the switching speed of the PIN diode is 10 MHz. In the multiplexing wireless communication experiment, the general-purpose metasurface antenna 400 generates two independent channels in different directions. Figure 49 On the receiver side, two horn antennas with different polarizations are located in the two main beam directions. The horns are connected to two VSAs for decoding the digital information of the two channels. Table 1 shows some characteristics of the metasurface antenna 400 embodiment.

[0248] Table 1 - Some characteristics of the Metasurface Antenna 400 embodiment

[0249]

[0250] The general-purpose metasurface antenna 400 embodiment can dynamically, simultaneously, independently, and precisely manipulate all the fundamental properties of electromagnetic waves in a software-defined manner. In this embodiment, the metasurface antenna 400 operates at microwave frequencies and utilizes PIN diodes as active elements. In this embodiment, the metasurface antenna 400 includes a subwavelength metaatom array located on top of a substrate integrated waveguide (SIW). Each metaatom includes two ±45° tilted slots for radiating two orthogonal eigenpolarization states (+45° linear polarization) and (45° linear polarization) in free space. Each slot can be independently switched in real time between a radiating state (“1”) and a non-radiating state (“0”) via a PIN diode. In this embodiment, the radiating state of the metaatom is time-modulated with a time period, and the injected monochromatic wave has a frequency of V. In this embodiment, an independent time-coded sequence applied to all metaatoms forms a two-dimensional (2D) “0 / 1” spatiotemporal coding (STC) matrix, which is controlled by a field-programmable gate array (FPGA). Our STC metasurface antenna can extract in-plane guided waves (GW) and convert them into out-of-plane propagating waves (PW) with arbitrary wave characteristics.

[0251] As will be understood by those skilled in the art, the present invention is not limited to the general metasurface antenna 400 embodiment.

[0252] More generally, some embodiments of the present invention provide a universal metasurface antenna whose metasurface structure (having multiple subwavelength elements) can control the radiation of one or more or all of the fundamental properties of electromagnetic waves, including amplitude, phase, polarization, frequency, and momentum. Some embodiments of the present invention provide a universal metasurface, which is a waveguide-fed temporally controlled metasurface capable of extracting and modulating guided waves into desired out-of-plane free-space waves. Some embodiments of the present invention incorporate PIN diodes in each superatom of the metasurface or metasurface antenna to switch elements between coupled (“1”) and uncoupled (“0”) states. In some embodiments, the coupling state of the superatom can be dynamically controlled by a controller (e.g., a field-programmable gate array (FPGA)) according to a pre-designed time sequence. Some embodiments of the present invention provide a universal metasurface antenna capable of dynamically, simultaneously, independently, and / or precisely manipulating one or more or all of the fundamental properties of electromagnetic waves. In some embodiments, the universal metasurface antenna further facilitates spatially and temporally varied wave characteristics, thereby enabling the generation of more complex waveforms, beamforming, direct information manipulation, etc. In some implementations, universal metasurface antennas can generate non-diffractive Airy beams and near-field focused beams. In some implementations, universal metasurface antennas can directly generate modulated waves carrying information, fundamentally simplifying the structure of information transmission systems. In some implementations, the complex wave and information processing of metasurface antennas is achieved by spatiotemporally switching the on-off encoded states of the metaatoms in the antenna metasurface structure. In some implementations, metasurface antennas possess multifunctionality and powerful electromagnetic wave and information manipulation capabilities, making them applicable to various fields ranging from next-generation information systems, cognitive sensing, and imaging to quantum optics and quantum information science.

[0253] Some embodiments of the present invention may have one or more of the following exemplary functions and applications. Some embodiments of the present invention may have one or more additional or alternative functions and / or applications not described or illustrated. For example, some embodiments of metasurface antennas can dynamically, simultaneously, independently, and precisely manipulate all fundamental properties of electromagnetic waves, including amplitude, phase, momentum, frequency, and polarization. For example, some embodiments of metasurface antennas can facilitate information manipulation by directly generating modulated waveforms with flexible wave characteristics, which may lead to a paradigm shift in new information transmission architectures. For example, some embodiments of metasurface antennas can achieve orbital angular momentum control (e.g., in two-dimensional cases). For example, some embodiments of metasurface antennas may include one or more of the following advantages, including full-dimensional wave controllability, inherently information-oriented modulation, simplified coding schemes (e.g., 1-bit), no sideband contamination, and potential on-chip integration, making metasurface antennas a highly attractive driving force for next-generation high-capacity and high-security information systems, cognitive sensing, imaging, and other applications.

[0254] Some embodiments of the present invention may include one or more of the following example advantages. Some embodiments of the present invention may include one or more additional or alternative advantages not described or illustrated. For example, some embodiments may provide a single metasurface device capable of manipulating multiple (e.g., all) fundamental properties (amplitude, phase, momentum, frequency, and polarization) of electromagnetic waves. For example, some embodiments alleviate or overcome one or more of the following problems: (i) the functionality of existing passive metasurfaces cannot be changed once fabricated; (ii) existing tunable metasurfaces lack sufficient degrees of freedom in terms of the geometric parameters of the elements and lack external control variables capable of supporting the adjustment of all wave characteristics; (iii) manipulation of independent electromagnetic wave characteristics is challenging because the control of these characteristics is often intercoupled. Some embodiments of the present invention provide a metasurface antenna that can dynamically, simultaneously, independently, and / or precisely manipulate all fundamental properties of electromagnetic waves, e.g., in a software-defined manner. Some embodiments of the present invention achieve complex and complete waveform control by simply switching the operating state of the metaatom (radiative and non-radiative; on and off) (e.g., 1-bit).

[0255] Those skilled in the art will understand that variations and / or modifications can be made to the embodiments described and / or illustrated in this invention to provide other embodiments of the invention. Therefore, the embodiments described and / or illustrated in this invention should be considered exemplary in all respects, not restrictive. Examples of optional features of certain embodiments of the invention are provided in the abstract and description. Some embodiments of the invention may include one or more of these optional features (some of which are not specifically illustrated in the figures). Some embodiments of the invention may lack one or more of these optional features (some of which are not specifically illustrated in the figures). In some implementations, the structure of the device may differ from that illustrated. For example, the shape, size, form, etc., of the metasurface structure and / or associated antenna and antenna system may differ from those illustrated. Metasurface structures and / or associated antennas and antenna systems can be used to process electromagnetic waves of different frequencies, not limited to microwaves. "Light" mentioned in some examples can be electromagnetic waves such as microwaves, millimeter waves, etc. Metasurface structures and / or associated antennas and antenna systems can be applied to various application areas (such as devices / systems), such as, but not limited to, cellular (e.g., 5G, 6G or above) communication, contactless sensing, RFID systems, Li-Fi (light-based internet access), lidar systems, etc. It is important to note that in embodiments where the metasurface structure includes subwavelength units capable of manipulating or controlling all five basic electromagnetic wave properties (amplitude, phase, polarization, frequency, and momentum), the metasurface structure does not always need to manipulate or control all five properties simultaneously; rather, the metasurface structure can manipulate or control any one or more or all of these properties simultaneously (i.e., the metasurface structure has the ability to manipulate or control all five properties, but during operation, it can arrange to manipulate or control any one or more (at most all five) properties).

Claims

1. A metasurface structure for an antenna, comprising: Multiple subwavelength units can manipulate or control the amplitude, phase, polarization, frequency, and momentum of radiated electromagnetic waves; Each of the plurality of subwavelength units comprises: The first trench, formed on or in the conductive layer, can radiate electromagnetic waves; the first trench can be used to radiate electromagnetic waves with a first characteristic polarization state. The second groove is formed on or in the conductive layer and can radiate electromagnetic waves; the second groove can be used to radiate electromagnetic waves with a second characteristic polarization state orthogonal to the first characteristic polarization state. A first control device operably coupled to the first slot for facilitating selective control of switching the first slot between radiating and non-radiating states; and A second control device operably coupled to the second tank for facilitating selective control of switching between the second tank in a radiating state and a non-radiating state; The first control device and the second control device can be controlled by a controller.

2. The metasurface structure according to claim 1, wherein the plurality of subwavelength units can dynamically manipulate or control electromagnetic... Wave amplitude, phase, polarization, frequency and / or momentum.

3. The metasurface structure according to claim 1, wherein the plurality of subwavelength units can simultaneously manipulate or control electromagnetic waves. At least two of the amplitude, phase, polarization, frequency, and momentum.

4. The metasurface structure according to claim 1, wherein the plurality of subwavelength units can independently manipulate or control electromagnetic waves. At least two of the amplitude, phase, polarization, frequency, and momentum.

5. The metasurface structure according to claim 1, wherein the plurality of subwavelength units can be dynamically, independently, and simultaneously Manipulate or control at least two of the amplitude, phase, polarization, frequency, and momentum of an electromagnetic wave.

6. The metasurface structure according to claim 1, wherein each of the plurality of subwavelength units is selectively... Switching between a first operating state and a second operating state facilitates control over the amplitude, phase, polarization, frequency, and / or amplitude of electromagnetic waves. The manipulation or control of momentum.

7. The metasurface structure according to claim 1, wherein: Both the first groove and the second groove are annular in shape; and The first slot and the second slot have different directions.

8. The metasurface structure according to claim 7, wherein: The first groove extends along the first axis; The second groove extends along the second axis; and The first axis and the second axis are arranged at a non-zero angle.

9. The metasurface structure according to claim 8, wherein the non-zero angle is 90 degrees.

10. The metasurface structure according to claim 8, wherein: The first slots of the plurality of subwavelength units have the same shape, size, and / or orientation; and The second slots of the plurality of subwavelength units have the same shape, size and / or orientation.

11. The metasurface structure according to claim 1, wherein: The first control device includes at least two control elements operably coupled to the first slot for influencing the operation of the first slot; as well as The second control device includes at least two control elements operably coupled to the second slot for influencing the operation of the second slot.

12. The metasurface structure according to claim 11, wherein: The at least two control elements of the first control device include a first semiconductor element and a second semiconductor element, each of the first semiconductor element and the second semiconductor element being selectively operable in an on state and an off state; as well as The at least two control elements of the second control device include a first semiconductor element and a second semiconductor element, each of which can selectively operate in an on state and an off state.

13. The metasurface structure according to claim 12, wherein: The first semiconductor element and the second semiconductor element of the first control device are arranged to operate simultaneously in the on state or the off state; as well as The first semiconductor element and the second semiconductor element of the second control device are arranged to operate simultaneously in the on state or the off state.

14. The metasurface structure according to claim 12, wherein: The first semiconductor element and the second semiconductor element of the first control device include positive and negative PIN diodes; and The first semiconductor element and the second semiconductor element of the second control device include positive and negative PIN diodes.

15. The metasurface structure according to claim 12, wherein: The first semiconductor element of the first control device is connected across a first slot portion of the first slot, and the second semiconductor element of the first control device is connected across a second slot portion of the first slot. as well as The first semiconductor element of the second control device is connected across the first slot portion of the second slot, and the second semiconductor element of the second control device is connected across the second slot portion of the second slot.

16. The metasurface structure according to claim 15, wherein: in, The first groove portion and the second groove portion of the first groove are located on opposite sides of the first groove; and The first groove portion of the second groove and the second groove portion of the second groove are located on opposite sides of the second groove.

17. The metasurface structure according to claim 16, wherein: The first semiconductor element and the second semiconductor element of the first control device are arranged along the axis of the first control device; The first semiconductor element and the second semiconductor element of the second control device are arranged along the axis of the second control device; as well as The axes of the first control device and the second control device are arranged at a non-zero angle.

18. The metasurface structure according to claim 12, wherein: The first semiconductor element and the second semiconductor element of the first control device are biased or arranged in the same bias state; and / or The first semiconductor element and the second semiconductor element of the second control device are biased or arranged in the same bias state.

19. The metasurface structure of claim 1, wherein the plurality of subwavelength units are arranged in an array and aligned.

20. A metasurface antenna, comprising: A waveguide is operable to guide electromagnetic waves; as well as Metasurface structures, the metasurface structures comprising: Multiple subwavelength units can manipulate or control the amplitude, phase, polarization, frequency, and momentum of radiated electromagnetic waves; Each of the plurality of subwavelength units comprises: The first groove is formed on or in the conductive layer and can radiate electromagnetic waves. The second groove is formed on or in the conductive layer and can radiate electromagnetic waves. A first control device operably coupled to the first slot for facilitating selective control of switching the first slot between radiating and non-radiating states; and A second control device operably coupled to the second tank for facilitating selective control of switching between the second tank in a radiating state and a non-radiating state; The first control device and the second control device can be controlled by a controller; The metasurface structure is operably coupled to the waveguide, and the metasurface structure is operably modulated and radiated with electromagnetic waves. The electromagnetic waves include in-plane waves, while the modulated electromagnetic waves include out-of-plane waves.

21. The metasurface antenna of claim 20, wherein the metasurface structure is at least partially integrated with the waveguide.

22. The metasurface antenna of claim 20, wherein the waveguide comprises a substrate-integrated waveguide.

23. The metasurface antenna according to claim 22, wherein: The substrate integrated waveguide includes: Dielectric substrate; A first conductive layer is disposed on one side of the dielectric substrate; A second conductive layer disposed within or on the dielectric substrate, and Multiple conductive elements are arranged in the dielectric substrate and electrically connected to the first conductive layer and the second conductive layer; and The metasurface structure is at least partially disposed on or within the first conductive layer.

24. The metasurface antenna of claim 23, wherein each of the plurality of subwavelength units of the metasurface structure is operatively coupled to two or more of the conductive elements.

25. The metasurface antenna of claim 23, wherein the second conductive layer includes a bias circuit having a plurality of bias circuit portions, each of the bias circuit portions being operatively coupled to one of the plurality of subwavelength units of the metasurface structure.

26. A metasurface antenna system, comprising: The metasurface antenna according to claim 21, and A controller operably coupled to the metasurface antenna to control the operation of the metasurface antenna.

27. The metasurface antenna system of claim 26, wherein the controller comprises one or more field-programmable gate arrays.

28. The metasurface antenna system of claim 26, wherein the controller is arranged to provide control signals to a plurality of subwavelength elements of the metasurface antenna to influence or control the operation of the plurality of subwavelength elements of the metasurface antenna in space and time, thereby facilitating manipulation or control of the amplitude, phase, polarization, frequency and / or momentum of electromagnetic waves.

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