Active Metasurface

Abstract

An active metasurface antenna and a method of using the same are disclosed. In some embodiments, the metasurface has a plurality of tuneable radiating antenna elements, each tuneable radiating antenna element comprising a tuning element configured to tune each tuneable radiating antenna element, and an amplifier coupled in parallel to the tuning element.

Description

Technical Field

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[0001] (Related Applications) This application claims priority to U.S. Patent Application No. 18 / 605,089, filed on March 14, 2024, which claims the benefit of U.S. Provisional Patent Application No. 63 / 452,846, filed on March 17, 2023, titled "Folded Iris Active Metasurfaces", and U.S. Provisional Patent Application No. 63 / 525,773, filed on July 10, 2023, titled "High-Performance Active Metasurfaces", and these applications are hereby incorporated by reference in their entirety.

[0002] (Technical Field) Embodiments of the present disclosure relate to wireless communication, and more particularly, the embodiments disclosed herein relate to active metasurface antennas.

Background Art

[0003] Metasurface antennas have recently emerged as another example of electronically steerable antennas that generate steerable beams from a lightweight and low-cost planar physical platform. Such metasurface antennas have recently been used in multiple applications such as satellite communication.

[0004] Metasurface antennas can include metamaterial antenna elements that can selectively couple energy from a feed wave to generate a beam that can be controlled for use in communication. These antennas can achieve performance comparable to phased array antennas from inexpensive and easily manufacturable hardware platforms.

[0005] In some electronically steerable antennas, the radiating antenna element includes a tuning element to control its operation. These tuning elements can be nonlinear devices that tune the antenna element as part of the process of generating a beam with the antenna element.

[0006] An active metasurface antenna and a method of using the same are disclosed. In some embodiments, the metasurface comprises a metasurface having a plurality of tuneable radiating antenna elements, each tuneable radiating antenna element including a gap, a pair of conductors disposed within the gap, a transistor coupled to the pair of conductors, a tuning element configured to tune each tuneable radiating antenna element, a capacitor coupled in series with the tuning element, and an amplifier coupled in parallel with the tuning element and the capacitor, wherein the first terminals of the tuning element and the amplifier are coupled to the first terminals of the transistor and the capacitor, and the output terminal of the amplifier is coupled to the second terminal of the transistor.

[0007] In some other embodiments, the antenna comprises a metasurface having radiating antenna elements and amplifiers configured to amplify the signals from the radiating antenna elements. In some embodiments, for each of the radiating antenna elements, the metasurface includes an antenna element and at least one of the following: a low-noise amplifier (LNA) coupled to a patch antenna and configured to amplify the signal received by the patch antenna for each radiating antenna element; a power amplifier (PA) coupled to the patch antenna and configured to amplify the signal transmitted from one radiating antenna element by the patch antenna; and a tuneable coupler coupled to the patch antenna using a wire cage. The coupler includes tuneable slots for coupling feeds to each radiating antenna element and tuning elements coupled to the tuneable slots for tuning the tuneable slots.

[0008] In several other embodiments, the antenna comprises a metasurface having a plurality of radiating antenna elements. In some embodiments, each of the plurality of radiating antenna elements includes: a cavity back antenna; at least one of a low-noise amplifier (LNA) coupled to the cavity back antenna and configured to amplify the signal received by the cavity back antenna for each radiating antenna element, and a power amplifier (PA) coupled to the cavity back antenna and configured to amplify the signal for transmission from one radiating antenna element by the cavity back antenna; and a tuneable coupler coupled to the cavity back antenna using a first wire cage having a first plurality of vias. The coupler may include tuneable slots for coupling feeds to each of the radiating antenna elements, and tuning elements coupled to the tuneable slots for tuning the tuneable slots.

[0009] Embodiments of the present invention and their advantages can be best understood by referring to the following description used in conjunction with the accompanying drawings. These drawings do not in any way limit any modifications of form and detail that can be made to the embodiments by those skilled in the art without departing from the spirit and scope of the embodiments of the present invention. [Brief explanation of the drawing]

[0010] [Figure 1] This is an exploded view of several embodiments of a flat panel antenna.

[0011] [Figure 2] This figure shows an example of a communication system including one or more antennas according to several embodiments.

[0012] [Figure 3A] This is a top view of the folding slot according to several embodiments of a radiating antenna element. [Figure 3B] This is a side view of a folding slot according to several embodiments of a radiating antenna element.

[0013] [Figure 4] FIG. 2 shows some embodiments of a radiation antenna element having a die with a resonator element, a capacitor, and an amplifier.

[0014] [Figure 5] FIG. 8 shows an alternative arrangement of the die along the length of the slot near the end of the slot.

[0015] [Figure 6] FIG. 14 is an exemplary diagram of using two dies for noise cancellation applications.

[0016] [Figure 7A] FIG. 20 is a top view of some embodiments of a unit cell of a metasurface structure. [Figure 7B] FIG. 23 is a side view of some embodiments of a unit cell of a metasurface structure.

[0017] [Figure 8A] FIG. 29 is a diagram showing some other embodiments of the unit cell. [Figure 8B] FIG. 32 is a diagram showing some other embodiments of the unit cell.

[0018] [Figure 9A] FIG. 38 is a diagram showing some other embodiments of a unit cell having an integrated varactor (resonator element) and an amplifier. [Figure 9B] FIG. 41 is a diagram showing some other embodiments of a unit cell having an integrated varactor (resonator element) and an amplifier. <000Q088>

[0019] [Figure 10] FIG. 47 is a block diagram of some embodiments of a metasurface configuration of a single die.

[0020] [Figure 11A] FIG. 53 is a side view of some embodiments of a unit cell of a metasurface structure. [Figure 11B]These are top views of several embodiments of a unit cell of a metasurface structure. [Figure 11C] These are top views of several embodiments of a unit cell of a metasurface structure.

[0021] [Figure 12A] Figures 11A to 11C are side views showing several embodiments of modified versions of the unit cell. [Figure 12B] Figures 11A to 11C are top views showing several embodiments of modified versions of the unit cell.

[0022] [Figure 13A] This is a side view of several embodiments of a radiating antenna element having an integrated varactor and LNA / PA. [Figure 13B] This is a top view of several embodiments of a radiating antenna element having an integrated varactor and LNA / PA.

[0023] [Figure 14A] This is a block diagram of several embodiments of a single diode that can be used in a metasurface configuration. [Figure 14B] This is a block diagram of several embodiments of a single diode that can be used in a metasurface configuration. [Modes for carrying out the invention]

[0024] In the following description, numerous details are given in order to provide a more complete description of the embodiments of the disclosure. However, it will be apparent to those skilled in the art that the teachings disclosed herein can be carried out without these specific details. In other instances, in order not to obscure the disclosure, well-known structures and devices are shown in the form of block diagrams rather than in detail.

[0025] This paper describes an antenna having an active metasurface with a high-performance configuration and a method of using the same. In some embodiments, the active metasurface includes an amplifier (PA / LNA) used in transmit and receive modes to amplify the signal. In some embodiments, the antenna includes a metasurface antenna with a single-layer amplifier incorporated into the metasurface to amplify the signal.

[0026] In some embodiments, the antenna has an active metasurface configuration having low reflection loss. This specification discloses an active metasurface that significantly reduces the reflection loss of these structures.

[0027] The following disclosure describes embodiments of antenna devices that may be part of the terminals described herein, followed by details of active metasurfaces with amplifiers integrated into the metasurface, high-performance active metasurfaces, and active metasurfaces having low reflection loss.

[0028] (Example of an antenna embodiment) The technology described herein can be used with various satellite antennas, such as flat-panel satellite antennas. Several embodiments of such flat-panel antennas are disclosed herein. In some embodiments, the flat-panel satellite antenna is part of a satellite terminal. The flat-panel antenna includes one or more arrays of antenna elements on an antenna aperture.

[0029] In some embodiments, the antenna aperture is a metasurface antenna aperture, such as the antenna aperture described below. In some embodiments, the antenna element comprises a radio frequency (RF) radiating antenna element. In some embodiments, the antenna element includes a tunable device for tuning the antenna element. Examples of such tunable devices include, for example, diodes and varactors as described in U.S. Patent No. 11,489,266, entitled "Metasurface Antennas Manufactured with Mass Transfer Technologies," issued November 1, 2022. In some other embodiments, the antenna element comprises a liquid crystal (LC) based antenna element, such as the one disclosed in U.S. Patent No. 9,887,456, entitled "Dynamic Polarization and Coupling Control from a Steerable Cylindrically Fed Holographic Antenna," issued February 6, 2018, or other RF radiating antenna elements. For example, but not limited to, other tuning devices such as tuning capacitors, tuning capacitance dies, package dies, micro-electromechanical systems (MEMS) devices, or other tuning capacitance devices may be placed in the antenna aperture or other locations in the variations of the embodiments described herein.

[0030] While the embodiments in this disclosure can derive several examples in communications, some embodiments can be implemented in a variety of receiving, transmitting, and / or sensing, or other similar applications. Some embodiments may include devices for sensing devices such as radar, lidar, sensors, and those in autonomous vehicle applications (but not limited to these), as well as any other applications that can utilize the attributes of the active metasurface according to various embodiments disclosed and undisclosed in this disclosure.

[0031] In some embodiments, an antenna aperture having one or more arrays of antenna elements is composed of a plurality of segments coupled together. In some embodiments, when coupled together, the combination of segments forms a group of antenna elements (e.g., a closed ring of antenna elements concentric with respect to the antenna feed). For more information on antenna segments, see U.S. Patent No. 9,887,455, “Aperture Segmentation of a Cylindrical Feed Antenna,” issued 6 February 2018.

[0032] Figure 1 shows exploded views of several embodiments of a flat panel antenna. Referring to Figure 1, the antenna 100 comprises a radome 101, a core antenna 102, an antenna support plate 103, an antenna control unit (ACU) 104, a power supply unit 105, a terminal housing platform 106, a COMM (communication) module 107, and an RF chain 108.

[0033] The radome 101 is the upper part of the housing that encloses the core antenna 102. In some embodiments, the radome 101 is made of a weather-resistant and radio wave-transparent material to allow the beam generated by the core antenna 102 to extend outside the radome 101.

[0034] In some embodiments, the core antenna 102 comprises an aperture having RF radiating antenna elements. These antenna elements function as radiators (or slot radiators). In some embodiments, the antenna elements comprise scattering metamaterial antenna elements. In some embodiments, the antenna elements comprise both receiving (Rx) and transmitting (Tx) irises, or slots, interleaved and distributed across the entire surface of the antenna aperture of the core antenna 102. Such Rx and Tx irises can be in groups of two or more sets, each set for a band that is controlled separately and simultaneously. An example of an antenna element having such irises is described in U.S. Patent No. 10,892,553, entitled "Broad Tunable Bandwidth Radial Line Slot Antenna," issued on January 12, 2021.

[0035] In some embodiments, the antenna element comprises an iris (iris aperture), and the antenna aperture is used to generate a shaped main beam using excitation from a cylindrical feed to radiate the iris aperture through a tunable element (e.g., a diode, varactor, patch, etc.). In some embodiments, the antenna element can be excited to radiate a horizontally polarized or vertically polarized electric field at a desired scan angle.

[0036] In some embodiments, tunable elements (e.g., diodes, varactors, patches, etc.) are arranged on each iris slot. The amount of power radiated from each antenna element is controlled by applying a voltage to the tunable element using a controller in the ACU 104. Traces to each tunable element in the core antenna 102 are used to supply voltage to the tunable element. This voltage tunes or detunes the capacitance and, consequently, the resonant frequency of the individual elements, thereby performing beamforming. The required voltage depends on the tunable element used. Taking advantage of this characteristic, in some embodiments, the tunable element (e.g., diodes, varactors, LCs, etc.) integrates an on / off switch for energy transmission from the feed wave to the antenna element. When the switch is turned on, the antenna element radiates electromagnetic waves like an electrically small dipole antenna. It should be noted that the teachings herein are not limited to having a unit cell that operates binary with respect to energy transmission. For example, in some embodiments where the varactor is the tunable element, there are 32 tuning levels. As another example, in some embodiments where the LC is a tunable element, there are 16 tuning levels.

[0037] To tune an antenna element (e.g., a tunable resonant element / slot), the voltage between the tunable element and the slot can be modulated. By adjusting the voltage, the capacitance of the slot (e.g., a tunable resonator / slot) changes. Therefore, by changing the capacitance, the reactance of the slot (e.g., a tunable resonator / slot) can be changed. The resonant frequency of the slot also changes according to the following equation.

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[0038] In particular, the generation of a focused beam by a metamaterial array of antenna elements can be explained by the phenomena of constructive and destructive interference, which are well known in the art. Individual electromagnetic waves, if they are in phase when they meet in free space, are added together (constructive interference) to generate a beam, and if they are out of phase when they meet in free space, they cancel each other out (destructive interference). If the slots of the core antenna 102 are arranged such that each consecutive slot is located at a different distance from the excitation point of the feed wave, the scattered waves from the antenna elements will have a different phase from the scattered waves of the previous slot. In some embodiments, if the slots are spaced at quarter wavelength intervals, each slot scatters a wave with a phase delay of quarter from the previous slot. In some embodiments, different patterns of constructive and destructive interference can be generated by controlling which antenna elements are turned on or off (i.e., changing the pattern of which antenna elements are turned on and which are turned off), or by controlling which of a plurality of tuning levels is used, and the antenna can change the direction of its beam.

[0039] In some embodiments, the core antenna 102 includes coaxial feeding used to provide cylindrical wave feeding via input feeding, such as described in U.S. Patent No. 9,887,456, entitled "Dynamic Polarization and Coupling Control from a Steerable Cylindrically Fed Holographic Antenna," issued on February 6, 2018, or U.S. Patent No. 11,489,266, entitled "Metasurface Antennas Manufactured with Mass Transfer Technologies," issued on November 1, 2022. In some embodiments, cylindrical wave feeding feeds the core antenna 102 from a central point with excitation that spreads cylindrically outward from the feeding point. In other words, cylindrical feeding is concentrically fed, propagating outward. Nevertheless, the shape of the cylindrically fed antenna around the cylindrical feeding can be circular, square, or any other shape. In some other embodiments, the cylindrically fed antenna aperture generates inwardly propagating fed waves. In such cases, the radio waves most inevitably originate from a circular structure.

[0040] In some embodiments, the core antenna comprises multiple layers. These layers include one or more substrate layers that form the RF radiating antenna element. In some embodiments, these layers may also include impedance matching layers (e.g., wide-angle impedance matching (WAIM) layers), one or more spacer layers, and / or dielectric layers. Such layers are well known in the art.

[0041] The antenna support plate 103 is coupled to the core antenna 102 and provides support for the core antenna 102. In some embodiments, the antenna support plate 103 includes one or more waveguides and one or more antenna feeds, providing the core antenna 102 with one or more feeds used by the antenna elements of the core antenna 102 to generate one or more beams.

[0042] The ACU104 is coupled to the antenna support plate 103 and provides a control unit for the antenna 100. In some embodiments, these control units include a control unit for the drive electronics for the antenna 100 and a matrix drive circuit for controlling a switching array scattered throughout the array of RF radiating antenna elements. In some embodiments, the matrix drive circuit drives each antenna element individually from the others, using a unique address for applying voltage to the tunable elements of the antenna elements. In some embodiments, the drive electronics of the ACU104 include a commercially available LCD control unit used in professional television equipment to regulate the voltage of each antenna element.

[0043] More specifically, in some embodiments, the ACU 104 supplies an array of voltage signals to the tunable elements of the antenna element to create a modulation or control pattern. The control pattern tunes the elements to different states. In some embodiments, the ACU 104 uses the control pattern to control which antenna elements are turned on or off (or which tuning levels are used) and which phase and amplitude levels are controlled at the operating frequency. The elements are selectively detuned for frequency operation by the voltage application. In some embodiments, multi-state control is used in which various elements are turned on and off at various levels, moving closer to a sinusoidal control pattern as opposed to a square wave (i.e., a sinusoidal gray-shaded modulation pattern).

[0044] In some embodiments, the ACU104 also includes one or more processors that run software for performing some of the control operations. The ACU104 can control one or more sensors (e.g., a GPS receiver, a 3-axis compass, a 3-axis accelerometer, a 3-axis gyroscope, a 3-axis magnetometer, etc.) to provide position and orientation information to the processor. Position and orientation information may also be provided to the processor by other systems of the earth station and / or may not be part of the antenna system.

[0045] Antenna 100 also includes a COMM (communication) module 107 and an RF chain 108. The communication module 107 includes one or more modems that enable Antenna 100 to communicate with various satellite and / or cellular systems, in addition to a router that selects an appropriate network route based on metrics (e.g., QoS (Quality of Service) metrics, e.g., signal strength, delay, etc.). The RF chain 108 converts analog RF signals into digital format. In some embodiments, the RF chain 108 comprises electronic components that may include amplifiers, filters, mixers, attenuators, and detectors.

[0046] The antenna 100 also includes a power supply unit 105 for supplying power to various subsystems or components of the antenna 100.

[0047] The antenna 100 also includes a terminal housing platform 106 that forms the housing at the bottom of the antenna 100. In some embodiments, the terminal housing platform 106 comprises several components that are coupled to other parts of the antenna 100, including a radome 101, in order to enclose the core antenna 102.

[0048] Figure 2 shows an example of a communication system including one or more antennas as described herein. Referring to Figure 2, the vehicle 200 includes antenna 201. In some embodiments, antenna 201 comprises antenna 100 of Figure 1. In some embodiments, the vehicle 200 may comprise any one of several vehicles, including, but not limited to, automobiles (e.g., cars, trucks, buses, etc.), marine vehicles (e.g., boats, ships, etc.), and aircraft (e.g., crew jets, military jets, small craft, etc.). Antenna 201 can be used for communication whether the vehicle 200 is stationary or moving. Antenna 201 can be used for communication to fixed locations, for example, remote industrial sites (mining, oil, gas) and / or remote renewable energy sites (solar power plants, wind power plants, etc.).

[0049] In some embodiments, the antenna 201 can communicate with one or more communication infrastructures (e.g., satellites, cellular networks (e.g., the Internet), etc.). For example, in some embodiments, the antenna 201 can communicate with satellites 220 (e.g., GEO satellites) and 221 (e.g., LEO satellites), a cellular network 230 (e.g., LTE, etc.), and network infrastructure (e.g., edge routers, the Internet, etc.). For example, in some embodiments, the antenna 201 includes one or more satellite modems (e.g., GEO modems, LEO modems, etc.) to enable communication with various satellites such as satellite 220 (e.g., GEO satellites) and satellite 221 (e.g., LEO satellites), and one or more cellular modems to communicate with the cellular network 230. For another example of an antenna communicating with one or more communication infrastructures, see U.S. Patent No. 11,818,606, titled "Multiple Aspects of Communication in a Diverse Communication Network," issued November 14, 2023.

[0050] In some embodiments, the antenna 201 performs dynamic beam steering to facilitate communication with various satellites. In such cases, the antenna 201 can dynamically change the direction of the beam it generates to facilitate communication with different satellites. In some embodiments, the antenna 201 includes multi-beam beam steering, which allows the antenna 201 to generate two or more beams simultaneously, thereby enabling the antenna 201 to communicate with two or more satellites at the same time. Such functionality is often used when switching between satellites (e.g., performing a handover). For example, in some embodiments, the antenna 201 generates and uses a first beam for communication with satellite 220 and simultaneously generates a second beam to establish communication with satellite 221. After establishing communication with satellite 221, the antenna 201 stops generating the first beam to end communication with satellite 220 and simultaneously switches to communication with satellite 221 using the second beam. For further details on multibeam communications, please refer to U.S. Patent No. 11,063,661, entitled "Beam Splitting Hand Off Systems Architecture," issued on July 13, 2021.

[0051] In some embodiments, the antenna 201 uses path diversity to allow a communication session occurring on one communication path (e.g., satellite, cellular, etc.) to continue during and after a handover to another communication path (e.g., another satellite, another cellular system, etc.). For example, if the antenna 201 is communicating with satellite 220 and switches to satellite 221 by dynamically changing the beam direction, the session with satellite 220 is coupled with the session occurring with satellite 221.

[0052] Accordingly, the antennas described herein can be part of a satellite terminal enabling ubiquitous communication and multiple different communication connections. In some embodiments, the antenna 201 comprises a metasurface RF antenna having multiple RF radiating antenna elements tuned to a desired frequency using an RF antenna element driving circuit. The driving circuit may include a driving transistor (e.g., thin-film transistor (TFT) (e.g., CMOS, NMOS, etc.), low-temperature or high-temperature polysilicon transistor, memristor, etc.), a micro-electromechanical system (MEMS) circuit, or other circuit for driving a voltage to the RF radiating antenna elements. In some embodiments, the driving circuit comprises an active matrix driving unit. In some embodiments, the frequency of each antenna element is controlled by an applied voltage. In some embodiments, this applied voltage is also stored in each antenna element (pixel circuit) until the next voltage write cycle.

[0053] Single-layer active metasurface Embodiments disclosed herein include an antenna having an active metasurface, in which an amplifier is incorporated into the metasurface to amplify signals received by and / or transmitted by the metasurface. In some embodiments, the metasurface comprises a single layer of tunable radiating antenna elements. In some embodiments, the tunable radiating antenna elements include a gap (e.g., a slot) as a means of realizing a single-layer active metasurface. In some embodiments, the amplifier is coupled across the gap. The amplifier receives an input signal at its input terminal, amplifies it, and provides the amplified signal at its output terminal. In some embodiments, the input terminal of the amplifier is coupled (e.g., connected) to two points of the antenna element to sample data (or input signal), while the output terminal of the amplifier excites the radiating portion (at its two points) of the antenna with the amplified signal. The input terminal of the amplifier may be coupled to a portion of the radiating portion of the antenna element, and the output terminal of the amplifier may be coupled to another portion of the radiating portion of the antenna.

[0054] In some embodiments, the gap comprises a slot. In some embodiments, the slot comprises a folding slot, which includes a pair of conductor folding sections within the slot. The folding conductors are coupled to a transistor. In some embodiments, the folding slots of multiple tuneable radiating antenna elements within a metasurface are single-layered. In some embodiments, the transistor comprises a gate, a source, and a drain, the gate and drain being coupled to either side or the edge of the slot extending longitudinally along the edge of the slot, and the source being coupled to the pair of folding conductors of the folding slot.

[0055] In some embodiments, tuning elements are coupled to each tunable radiating antenna element to tune the folding slots. In some embodiments, a capacitor is coupled in series with the tuning element (e.g., connected), and an amplifier is coupled in parallel with the series-coupled tuning element and capacitor (e.g., connected). In some embodiments, the tuning element includes a varactor. In some embodiments, the capacitor comprises a metal-insulator-metal (MIM) capacitor. In some embodiments, the combination of tuning element, capacitor, and amplifier is contained in a single die that spans and is coupled (e.g., connected) over a portion of each folding slot. In some embodiments, the terminals of the tuning element and amplifier are coupled to the gates of transistors coupled to the folding slots as described above, and the other terminals of the capacitor and amplifier are coupled to the drains of those transistors.

[0056] Figures 3A and 3B show top and side views of folding slots in several embodiments of a radiating antenna element. Such a radiating element can be part of the metasurface of an antenna. Referring to Figures 3A and 3B, the conductor 302 includes a slot (iris) 301. In some embodiments, the conductor 302 includes copper or any other metal or conductive material. The slot 301 includes two conductors 301A and 301B that extend through the central portion of the slot 301 as the slot 301 extends in the longitudinal direction. A transistor having a drain 305, a source 306 and a gate 307 is coupled (e.g., connected) to the slot 301. In some embodiments, the transistor is connected to conductors 301A and 301B, which are the folding portion of the slot 301. In some embodiments, the source 306 of the transistor is connected to the folding portion of the slot 301, which is short-circuited and connected to the side edge of the slot 301. In Figure 3A, two irises are stacked horizontally. In some embodiments, the electric field may be weaker at the edge of slot 301, so connecting the folded conductors 301A and 301B to the body of conductor 302 may or may not change the electric field distribution. In some embodiments, the drain 305 of the transistor is connected or coupled to one side of slot 301 (the upper edge of the slot in Figure 3A), and the gate 307 is connected or coupled to the other side of slot 301 (the lower edge of the slot in Figure 3A). This topology can be used, for example, for common-source amplification on a radiating antenna element (e.g., by a common-source amplifier).

[0057] In some embodiments, the die 303 is coupled to the width of the slot 301 and coupled across (over) the width of the slot 301. In some embodiments, the die 303 includes a tuning element (e.g., a varactor, MEMS, patch, etc.) for tuning the slot 301. In some embodiments, the die 303 includes a capacitor (e.g., an MIM, a capacitor in series with the tuning element, etc.). In some embodiments, the die 303 includes an amplifier (e.g., a common-source amplifier, a common-drain amplifier, etc.). In some embodiments, the die 303 includes a tuning element, a capacitor, and an amplifier.

[0058] In some embodiments, the die 303 is coupled to the width of the slot 301 at a central position along the length of the slot 301, and in some embodiments, it is coupled across (on top of) the width of the slot 301. However, this central positioning is not a requirement, and in some other embodiments, the die 303 is coupled to the width of the slot 301 at other positions along the length of the slot 301, and in some embodiments, it is positioned across (on top of) the width of the slot 301. In various embodiments, the position or arrangement of the die 303 (e.g., varactor + MIM capacitor + amplifier) ​​can be changed inside or relative to the slot 301 (aperture).

[0059] Figure 5 shows an alternative die arrangement along the length of slot 301, near the end of slot 301. Referring to Figure 5, in some embodiments, the slot has a length and width, and a die 501, for example, a single die, is coupled across its width at a position offset from the center of its length. Die 501 can be die 303 in Figures 3A and 3B. Note that the die 501 arrangement in Figure 5 is an example, and die 501 can be positioned at different locations along its length, for example, based on the voltage and current that vary within slot 301. This is particularly useful when configuring slot 301 to a desired frequency, as losses can be controlled. In such cases, depending on the different amplifier, MIM, and varactor components that can be used in the die, the die can be selectively positioned, e.g., moved or offset, from the center of slot 301, allowing slot 301 to operate properly at the desired frequency.

[0060] Figure 3B shows several embodiments of a stack-up located below a metasurface. The techniques disclosed herein are not limited to using the stack-up shown in Figure 3B, but can be used with other stack-ups. Referring to Figure 3B, the stack-up 320 includes a substrate 321 coupled to a conductor 302. In some embodiments, the substrate 321 comprises a printed circuit board (PCB). However, the substrate 321 may include other materials. A coupler 323 is coupled to the substrate 321, and a waveguide 322 is coupled to the coupler 323. In some embodiments, the waveguide 322 propagates the fed signal that coupler 323 couples to the substrate 321, where the fed signal propagates to the slot 301 as a radiating antenna element and interacts with the slot 301.

[0061] In some embodiments, die 303 provides an advanced design of tuning and amplification topologies for the two purposes of tuning and amplification. In some embodiments, the topology includes a series connection of tuning elements (varactors) and fixed capacitors (MIM capacitors) and an amplifier connected in parallel with tuning elements such as varactors and fixed capacitors connected in series.

[0062] Figure 4 shows several embodiments of a foldable slot antenna element having a die comprising a tuning element, a capacitor, and an amplifier. This die can be used as die 303 in Figures 3A and 3B. Referring to Figure 4, the varactor 411 is connected or coupled in series with the MIM capacitor 412. The input of the varactor 411 is coupled to terminal 421, and the MIM capacitor 412 is coupled to terminal 422. In some embodiments, the amplifier 413 is connected or coupled in parallel to the series connection of the varactor 411 and the MIM capacitor 412. In some embodiments, terminal 422 connecting the amplifier 413 to the MIM capacitor 412 is connected or coupled to the drain 305 of the transistor, and terminal 421 connecting the amplifier 413 to the varactor 411 is connected or coupled to the gate 307 of the transistor. In some embodiments, the amplifier 413 is a single-transistor amplifier in which the drain (D) of terminal 421 is connected or coupled to the gate 307, and the gate (G) of terminal 422 is connected or coupled to the drain 305. Amplifier 413 can be of different types. For example, amplifier 413 can be, but is not limited to, a Class A, Class AB, high-power, low-power, or Tx / Rx amplifier. Conductor 420 functions as a reference voltage and a virtual AC (RF) ground.

[0063] In some embodiments, the tuning operation for tuning the radiating antenna element is performed using a varactor 411 and a MIM capacitor 412. Figure 4 also shows the arrangement of the amplifier 413 and the rest of the die. In some embodiments, the amplifier 413 is arranged in parallel with the resonator of the radiating antenna element that, together with the varactor 411 and the MIM capacitor 412, constitutes slot 301. The amplifier 413 acts on the received signal or the transmitted signal, respectively, when slot 301 is used for reception (when the antenna receives a signal) or transmission (when the antenna transmits a signal). The side view of the antenna element is the same as in Figure 3B.

[0064] During operation, in some embodiments, during transmission, the fed signal propagates through a waveguide and, via a coupler, is tuned by a varactor (or other type of tuning element) and coupled to a folding slot that is amplified by an amplifier (e.g., a power amplifier) ​​within the die, and then transmitted by a radiating antenna element. During reception, while the varactor tunes the folding slot, the antenna element receives the signal amplified by an amplifier (e.g., a low-noise amplifier) ​​within the die, and is then coupled from the tuneable folding slot to the waveguide.

[0065] In some embodiments, two or more dies (e.g., die 303) can be coupled to a slot for noise cancellation purposes. For example, Figure 6 shows the use of two dies for noise cancellation applications. The two dies may include different amplifier combinations for noise cancellation applications. In some embodiments, each die includes a varactor, an MIM capacitor, and an amplifier as described above in Figures 4 and 5. In some embodiments, the amplifiers of die 610 and die 611 are different, but the varactor and MIM capacitor are the same. Alternatively, the varactor and MIM capacitor of die 610 and die 611 are different, but the amplifiers are the same. However, in some other embodiments, the components of die 610 and die 611 are different from each other. Other configurations are intended to be within the scope of this disclosure.

[0066] From a noise perspective, noise from a common-gate (CG) amplifier exhibits different polarities at its source and drain nodes. In some embodiments, the noise at the source terminal further drives an antenna, exciting the same standing wave noise voltage distribution across the slot, and thus resulting in the same noise polarity at the input of the common-source (CS) stage. After passing through the CS path, the noise polarity changes. Ultimately, the noise polarity becomes the same at the CG / CS output. As a result, the noise (from the CG amplifier) ​​is canceled out.

[0067] Referring to Figure 6, dies 610 and 611 are connected or coupled above a slot 601 containing folded conductors 631 and 632, in some embodiments. A gap 620 exists between the folded conductors 631 and 632 such that their ends are not electrically connected. In some embodiments, a current null is established at the center of the folding slot 601 by removing a small portion of the conductor in the gap 620. As a result, the central part of the antenna is opened, allowing the application of various CG / CS bias voltages without impairing the antenna's characteristics. In some embodiments, the gap can be reduced to about 100-200 micrometers. The gap 620 provides the option to operate two amplifiers within the slot for noise cancellation purposes.

[0068] In some embodiments, one terminal of die 610 is connected to or coupled to the gate 607 of a first transistor whose source 606 is short-circuited to a folded conductor 631, the other terminal of die 610 is connected to or coupled to the drain 605 of the first transistor, one terminal of die 611 is connected to or coupled to the gate 617 of a second transistor whose source 616 is short-circuited to a folded conductor 632, and the other terminal of die 611 is connected to or coupled to the drain 615 of the second transistor. In some other embodiments, one terminal of die 610 is connected to or coupled to the gate 607 of a first transistor whose source 606 is shorted to a folded conductor 631, the other terminal of die 610 is connected to or coupled to the drain 605 of the first transistor, one terminal of die 611 is connected to or coupled to the source 616 of a second transistor whose gate 617 is shorted to a folded conductor 632, and the other terminal of die 611 is connected to or coupled to the drain 615 of the second transistor. The side view of the antenna element in Figure 6 is the same as in Figure 3B, except that there are two dies instead of one.

[0069] One or more advantages of the one or more metasurface embodiments having folding slots described herein include improved gain / noise temperature performance of the receiving (Rx) antenna, reduced power consumption, reduced complexity in manufacturing the active metasurface, a more highly integrated terminal design, and a smaller height profile.

[0070] High-performance active metasurface Several embodiments described herein include antenna element architectures connected in series with a power amplifier as high-performance transmit (Tx) and receive (Rx) unit cells in active metasurfaces. In some embodiments, a power amplifier having high gain and high power-added efficiency is integrated with the radiating unit cell for use in transmit mode (when the antenna transmits a signal), while in receive mode (when the antenna receives a signal), an amplifier having low noise figure, moderate gain, and extremely low power consumption is integrated with the radiating element. Many structures, including active radiating elements, tunable elements, matching circuits, antenna elements, couplers, etc., can be used in active metasurfaces, but many of these cannot achieve one or more performance indicators. For example, there are many challenges and trade-offs, such as stability, power consumption, gain, noise figure, size, tunability (direct modulation), and power-added efficiency, and only a few designs can successfully overcome these challenges. Several embodiments disclosed herein include active metasurface unit cells that perform well in Tx and Rx modes and can be used in active metasurface structures.

[0071] Some embodiments of the disclosed metasurface unit cell include one or more of the following novel features: 1) Insulation between the antenna radiator, coupler, and waveguide is improved. As a result, radiation within the waveguide is reduced and the reflection coefficient is improved. 2) A coupler that is well-designed to prevent spurious radiation from the coupler into free space. Furthermore, instability can be avoided by reducing the coupling between the antenna and the coupler. In this way, power amplifiers (PAs) and low-noise amplifiers (LNAs) can be designed more flexibly and easily due to their unconditional stability. 3) High gain, low noise figure, and high power-added efficiency. High performance can be achieved due to design flexibility. 4) In Tx, the signal is first modulated, then amplified by a power amplifier, and transmitted by an electrically small antenna. In Rx, the signal is received by the antenna, amplified with a low noise figure using an LNA, and the amplified signal is modulated by a varactor. Using an amplifier in receive mode improves the noise figure because there is a loss element (such as a varactor) after the LNA.

[0072] Due to size constraints, antennas are electrically small, having low resistance and high capacitance, which significantly reduces efficiency. In some embodiments, wide-angle impedance matching (WAIM) improves efficiency by matching the antenna impedance to the impedance of free space. Also, designing electrically small antennas close to the Chu limit improves the efficiency of the metasurface unit cell. Embodiments disclosed herein have one or more improvements. A. Transmitting (Tx) side: 1. Improved power addition efficiency, 2. Low power consumption, 3. High gain, 4. Unconditional stability, 5. Low mutual coupling between antenna, coupler and waveguide, 6. High efficiency. B. Receiving (Rx) side: 1. Extremely low noise figure and high gain / noise performance, 2. High gain, 3. Unconditional stability, 4. Low power consumption, 5. Low mutual coupling between antenna, coupler and waveguide, 6. High efficiency, 7. Improved tunability.

[0073] In some embodiments, the unit cell has four main components: a tunable coupler, an LNA / PA with matching circuits, an antenna, and a WAIM. The coupler tunes the magnitude and phase of the signal coming from the waveguide (in the case of Tx) or the antenna / LNA (in the case of Rx). In Tx, the PA amplifies the signal with high gain and high power-added efficiency. In Rx, the LNA amplifies the signal with low noise performance and moderate gain. The antenna transmits / receives signals in Tx / Rx modes, respectively. The WAIM also improves efficiency by converting the free-space impedance to an impedance that can better match the antenna impedance. The WAIM also improves the metasurface performance for wide scans.

[0074] In some embodiments, the antenna includes a metasurface having a radiating antenna element and an amplifier configured to amplify the signal for the radiating antenna element. In some embodiments, each of the radiating antenna elements includes a ground patch antenna. However, the techniques disclosed herein are not limited to ground patch antennas. For example, in some embodiments, the radiating antenna element may include, but is not limited to, a spiral antenna, a loop antenna, and any other electrically small antenna having an efficiency-bandwidth product close to the Chu limit. In some embodiments, each of the radiating antenna elements also includes one or both of a low-noise amplifier (LNA) coupled to the antenna and configured to amplify the signal after it has been received by the antenna, and a power amplifier (PA) coupled to the antenna and configured to amplify the signal transmitted by the antenna. In some embodiments, the ground patch antenna is electrically short-circuited to a ground plane (e.g., metal or other conductive layer). In some embodiments, the ground patch antenna is electrically short-circuited to a ground plane using a plurality of vias (e.g., conductors, wires).

[0075] In some embodiments, the antenna also includes a tuneable coupler coupled to a patch antenna using a wire (via) cage (e.g., a via cage having multiple vias). The coupler may include tuneable slots for coupling feeds to a radiating antenna element, and tuning elements (e.g., varactors, MEMS, etc.) coupled to the tuneable slots for tuning the tuneable slots. In some embodiments, the LNA is coupled between the tuning elements (e.g., varactors, etc.) and the patch antenna.

[0076] In some embodiments, a set of vias traverses the substrate and is coupled to or toward a first side of a conductive layer containing slots, and one or more transmission lines (e.g., microstrip lines). The conductive layer is coupled to one side of the substrate, and the one or more transmission lines are coupled to or toward a second side of the substrate that is different from or opposite to the first side of the substrate. In some embodiments, a tuning element (e.g., a varactor) is coupled across a slot on the second side of the conductive layer that is different from or opposite to the first side of the conductive layer. The tuning element is coupled to the second side of the substrate and can be connected to or coupled to at least one of these one or more transmission lines at positions across and across the slots. In some embodiments, the tuning element is coupled to the conductive layer using vias in a wire cage. In some embodiments, the conductive layer is a ground layer.

[0077] Figures 7A and 7B show top and side views of several embodiments of a unit cell of a metasurface structure. Referring to Figures 7A and 7B, the metasurface structure includes a varactor (or tunable element) 703, a tunable slot 706 which is part of a coupler 700, an LNA 720 / PA 730, a patch (static) antenna 702 grounded using a wire (e.g., via) wall 760, and a WAIM 762. In some embodiments, the coupler 700 is housed in a via cage 761 containing a plurality of vias (wires). The via cage 761 traverses the substrate 701 from a microstrip line 705 to a metal layer 710. In some embodiments, the patch antenna 702 is electrically grounded using a via (wire) wall 760 containing a plurality of vias (wires).

[0078] During operation, the input signal is received by a patch antenna 702 mounted on the substrate 701. At this point, no modulation (e.g., amplitude and / or phase shift for beamforming) is applied to the received signal. In some other embodiments, other types of radiating antenna elements can be used. The received signal is then carried to the LNA 720 via a microstrip line 704 (or other transmission line (e.g., CPW)) mounted on the substrate 701, where the received signal is amplified. A microstrip line 705 (or other transmission line) mounted on the substrate 701 transmits the amplified signal from the LNA 720, and its energy is coupled to the waveguide 707 via a tunable (coupling) element / slot 706 in the metal layer 710. At this stage, while the amplified received signal is coupled to the waveguide 707, modulation (e.g., holographic modulation) is applied and its phase and / or amplitude is adjusted for beamforming using a tuning element coupled across the tunable slot 706 and loaded into the tunable slot. In some embodiments, the tuning element is a varactor 703, and this architecture assumes that all varactors within each unit cell are individually controllable. Therefore, the varactor 703 (or another type of tuning element) can adjust the impedance to introduce a phase shift in the signal and perform modulation. The hologram is created in the coupling layer and not in the radiating element.

[0079] During transmission, the wave propagates through waveguide 707 to tuneable slot 706 and is phase-shifted as it is coupled to microstrip 705 via tuneable slot 706. Varactor 703 is tuned to modulate the transmitted signal (e.g., creating a hologram in the coupling layer rather than the radiating element). The modulated signal is coupled to microstrip line 705 and travels through PA 730, where the transmitted signal is amplified and then passed through microstrip line 704 to patch antenna 702, which radiates the transmitted signal. Note that LNA 720 and PA 730 are separate electronic components, although they are shown together for convenience in Figures 7A and 7B.

[0080] In this configuration, the radiating portion of the metasurface is isolated from the waveguide 707, thereby enabling stable high gain. Stability is unconditional because the coupling between the input and output of PA730 / LNA720 is significantly reduced. Another advantage of this configuration is that the coupler does not radiate by having a via (wire) cage 761 with multiple vias (wires). The via cage 761 can be designed or configured to reduce, and potentially avoid, interference between radiation from the coupler 700 and the patch antenna 702. In some embodiments, the spacing between vias in the via cage 761 is not greater than the diameter or thickness of the vias themselves.

[0081] In some embodiments, where the antenna is electrically small and has low radiation resistance, electrically small means that the antenna size is small compared to the operating wavelength (proportional to the reciprocal of the frequency). In some embodiments, the electrically small antenna is designed to provide the highest possible radiation resistance (close to the Chu limit) across the target frequency band, thereby improving efficiency. In some embodiments, these characteristics are due to a via (or wire) wall 760 that electrically shorts the rear end of the patch antenna 702. Since the varactor 703 is positioned after the LNA 720 in receive (Rx) mode, the noise figure of this configuration is extremely low.

[0082] Figures 8A and 8B show several other embodiments of the unit cell. To reduce costs, in some embodiments, the varactor can be placed on a printed circuit board (PCB) (or other board) by using pads and connecting vias. Manufacturing costs can be reduced by connecting components such as the varactor (tuning element), LNA / PA, and patch antenna after the stack-up has been created. In this new configuration as well, the slot (iris) can be tuned by the varactor (tuning element) placed on the PCB. The coupler, LNA / PA, antenna, and WAIM remain largely unchanged.

[0083] Figures 8A and 8B show derivative architectures of the concepts in Figures 7A and 7B in several embodiments. Referring to Figures 8A and 8B, the difference in this architecture is that the varactor moves to the upper or adjacent to, continuous with, near, and / or above the microstrip layer while maintaining the load and tuning to the coupling slot on the bottom surface of the substrate. This architecture has the advantage that all discrete components (e.g., varactor, LNA, PA, etc.) are located on the same side of the substrate, simplifying the manufacturing process for this architecture. Furthermore, the drive circuits required for varactor tuning and LNA driving are on the same side as the discrete components. This arrangement further reduces manufacturing complexity. As shown in Figures 8A and 8B, through vias can also be used to couple or connect the varactor to the tunable slot on the bottom surface of the substrate and load the varactor.

[0084] Referring to Figures 8A and 8B, in some embodiments, during operation, a static patch antenna 802 mounted on the substrate 801 receives the input signal. At this point, the received signal is not modulated (e.g., amplitude and / or phase shift for beamforming). In some other embodiments, other types of antenna elements can be used. The received signal is then transmitted to the LNA 820 via a microstrip line 804 (or other transmission line e.g., CPW) mounted on, positioned, or coupled to the substrate 801, where the received signal is amplified. A microstrip line 805 (or other transmission line) coupled to the substrate 801 transmits the amplified signal from the LNA 820, and its energy is coupled to the waveguide 807 via a tunable coupling element / slot 806 in the metal layer 810. At this stage, while the amplified received signal is coupled from the microstrip line 805 to the waveguide 807 via the tunable slot 806, modulation is applied and its phase and / or amplitude is tuned for beamforming through the use of a tuning element that is coupled across the microstrip line on the substrate 801 and loads the tunable slot 806. In some embodiments, the tuning element is a varactor 803, and this architecture assumes that the varactors in all unit cells are individually controllable. Thus, the varactor 803 can tune its impedance to cause a phase shift in the signal in order to perform modulation.

[0085] According to some embodiments, during operation and transmission, the wave propagates through waveguide 807 to tuneable slot 806 and is phase-shifted when coupled to microstrip 805 via tuneable slot 806. Varactor 803 is tuned to modulate the transmitted signal (e.g., creating a hologram in the coupling layer rather than the radiating element). The modulated signal is coupled to microstrip 805 and travels through PA 830, where the transmitted signal is amplified and passed through microstrip line 804 to patch antenna 802, which radiates the transmitted signal. Note that, although shown together in Figures 8A and 8B for convenience, in some embodiments, LNA 820 and PA 830 are separate electronic components.

[0086] Similar to Figures 7A and 7B, the couplers in Figures 8A and 8B do not radiate by having a via (wire) cage 861 having a plurality of vias (wires) coupled or otherwise attached between the metal layer 810 and both microstrip lines 816 and 805. The via cage 861 is designed or configured to reduce and potentially avoid interference between radiation from the coupler 800 and the patch antenna 802. In some embodiments, the spacing between vias in the via cage 861 is not greater than the diameter or thickness of the vias themselves.

[0087] In some embodiments, the varactor is located in the die with one or both of the LNA and PA. Figures 9A and 9B show some embodiments in which the LNA / PA and varactor (tuning element) are integrated for further cost reduction. In some embodiments of this configuration, the varactor still tunes the reactance across the slot (iris), and there are two connecting vias 962, 963 connecting the varactor 903 to the slot (in parallel). This allows the slot 906 to tune to a resonant frequency.

[0088] In some embodiments, the varactor 903 and LNA 920 / PA 930 are designed together on a single die to reduce their size and cost. This also reduces losses, increases efficiency, and improves the noise figure (in Rx). Figure 10 is a block diagram of several embodiments of a single-die metasurface configuration. High-performance metasurface structures are implemented using specific couplers, varactors, LNAs / PAs, and antennas, but different designs can be achieved by modifying / changing the coupler or antenna. Referring to Figure 10, the slot (coupling iris) 1001 is coupled to a tunable coupler 1000, which includes a single die 1002 having one or both of the varactor 1010 and LNA / PA 1011. The tunable coupler 1000 is coupled to the antenna 1003. Note that, although shown together for convenience in Figure 10, in some embodiments, the LNA and PA of the LNA / PA 1011 are separate electronic components.

[0089] In some of the embodiments described above, the following advantages are included: extremely low noise figure and higher gain / noise performance in receive (Rx) mode; high gain with unconditional stability; high efficiency; excellent tuning; and / or compatibility with PCB design processes for low-cost design.

[0090] Low reflection loss active metasurface Several embodiments include active metasurface configurations with low reflection loss. In transmit (Tx) mode, integrating power amplifiers (PAs) into the metasurface structure of each slot (iris) can result in high reflection loss due to bilateral radiation of the slot. This power loss not only reduces efficiency but can also damage active elements behind the antenna, such as amplifiers. Similarly, efficiency can be reduced in receive (Rx) mode. In some embodiments, active metasurfaces significantly reduce the reflection loss of these structures.

[0091] Integrated amplifiers with slots can cause significant power reflection to the source because the slots have bilateral radiation. This is more pronounced in Tx modes where the power amplifier has high gain. In some embodiments, antenna architectures solve the problem of reflection loss in active metasurfaces. In some embodiments, the disclosed structures include an active amplifier element (PA / LNA), a tunable element (e.g., a varactor), a matching circuit (e.g., for load matching), an antenna element (e.g., a patch antenna), a coupler (e.g., a slot (iris) as a tunable coupler coupling energy to the PA or LNA), and a WAIM. In addition to reflection reduction, in some embodiments, these configurations with low reflection loss can provide good stability (e.g., unconditionally stable when faced with environmental changes (e.g., environmental temperature changes)), low power consumption, high gain, low noise figure (in Rx), fine tuning (direct modulation), and high power added efficiency (in Tx). In some embodiments, the antenna is designed based on metrics related to low power consumption, high gain, low noise figure (in Rx), fine tuning (direct modulation), and / or high power added efficiency (in Tx), and the trade-offs associated with each of these.

[0092] The following are novel features of several embodiments of a metasurface unit cell having an antenna element with an amplifier (e.g., LNA, PA, etc.) and a varactor (or other tuning element) for use in antennas with low reflection loss: 1) Improve the insulation between the radiator (patch antenna, etc.), coupler, and waveguide. As a result, radiation inside the waveguide is reduced, and reflection becomes extremely low. 2) Due to design flexibility, it has high gain, low noise figure, and high power addition efficiency. 3) In Tx, the signal is first modulated, then amplified by a power amplifier, and transmitted by the antenna. In Rx, the signal is first received by the antenna, amplified using an LNA to achieve a low noise figure, and then the amplified signal is modulated by a varactor. The presence of a loss element (varactor) after the LNA improves the noise figure.

[0093] The low reflection loss embodiments described herein offer one or more improvements: on the transmitting (Tx) side, low coupling between the antenna and the waveguide and high efficiency; and on the receiving (Rx) side, extremely low noise figure, low coupling between the antenna and the waveguide and high efficiency.

[0094] In some embodiments, the unit cell includes a tunable coupler, an LNA / PA having matching circuits, an antenna, and a WAIM. The coupler tunes the magnitude and phase of signals coming from the waveguide (in the case of Tx) or the antenna / LNA (in the case of Rx). The PA in Tx amplifies the signal with high gain and high power-added efficiency. In Rx, the LNA amplifies the signal with low noise performance and moderate gain. The antenna transmits / receives signals in Tx / Rx modes, respectively. The WAIM also improves efficiency by converting the free-space impedance to an impedance that can better match the antenna impedance. The WAIM also improves the metasurface performance for wide scans.

[0095] Figures 11A–11C show several embodiments of top and side views of a unit cell of a metasurface structure. The top view is shown in different layers (Z1 and Z2). The structures disclosed in Figures 11A–11C include a tunable slot, cavity, LNA / PA (for receiving / transmitting), patch antenna, and WAIM, which are part of a tunable coupler. In some embodiments of this configuration, the radiating section (antenna and cavity formed by via (e.g., wire) cage) is isolated from the waveguide section, thereby achieving stable high gain. Stability is unconditional due to the significantly low coupling between the input and output of the PA / LNA.

[0096] Figures 11A and 11B show top and side views of several embodiments of a unit cell of a metasurface structure. Referring to Figures 11A and 11B, the waveguide 1107 propagates the fed radio waves into the metasurface structure. A metal layer 1110 is coupled to the waveguide 1107 and includes a tuneable slot 1106. A substrate 1101 is coupled to the top of the metal layer 1110. The metal layer 1111 is coupled to the top of the substrate 1101 and includes a slot on the tuneable slot 1106 and a gap on the cavity 1171, which together with the antenna 1102 forms a cavity back antenna. The metal layer 1111 is coupled to the metal layer 1110 by two via (wire) cages 1160 and 1161, each having multiple vias (conductors (e.g., wires)). The via cage 1161 is part of the tuneable coupler 1100. The via cage 1160 is the side around the cavity 1171. The substrate 1170 is coupled to the top of the metal layer 1111. A microstrip (or other transmission line) 1105 is coupled to the top of the substrate 1170 and to the LNA 1120 / PA 1130. The LNA 1120 / PA 1130 is coupled to the metal layer 1111. In some embodiments, the LNA 1120 / PA 1130 is electrically connected to the metal layer 1111 using connecting vias 1163 (or other conductors). The LNA 1120 / PA 1130 is coupled to the antenna 1102 using a microstrip 1104 coupled to the top surface of the substrate 1170. Note that although they are shown together in Figures 11A and 11B for convenience, the LNA 1120 and PA 1130 are separate electronic components.

[0097] The metasurface structure includes a varactor (or tuneable element) 1103, a tuneable slot 1106 which is part of a tuneable coupler 1100, an LNA 120 / PA 1130, an antenna 1102 having a cavity 1171 formed by a via cage 1160, and a WAIM 1162. In some embodiments, the antenna 1102 comprises a patch antenna.

[0098] During operation, the input signal is received by the antenna 1102 mounted on the substrate 1170. At this point, the received signal is not modulated (e.g., amplitude and / or phase shift for beamforming). In some other embodiments, other types of radiating antenna elements can be used. The received signal is then carried to the LNA 1120 via a microstrip line 1104 (or other transmission line (e.g., CPW)) mounted on the substrate 1101, where the received signal is amplified. A microstrip line 1105 (or other transmission line) mounted on the substrate 1101 transmits the amplified signal from the LNA 1120, and its energy is coupled to the waveguide 1107 via a tunable (coupling) element / slot 1106 in the metal layer 1110. At this stage, while the amplified received signal is coupled to waveguide 1107, modulation (e.g., hologram modulation) is applied and coupled across tuneable slot 1106, and its phase and / or amplitude is tuned for beamforming using a tuning element that loads the tuneable slot. In some embodiments, the tuning element is a varactor 1103, and this architecture assumes that varactors in all unit cells can be controlled individually. Thus, the varactor 1103 (or another type of tuning element) can be tuned to tune its impedance to cause a phase shift in the signal in order to perform modulation. The hologram is created in the coupling layer and not in the radiating element.

[0099] During transmission, the wave propagates through waveguide 1107 to tuneable slot 1106 and is phase-shifted when coupled to microstrip 1105 via tuneable slot 1106. Varactor 1103 is tuned to modulate the transmitted signal (for example, by creating a hologram in the coupling layer rather than the radiating element). The modulated signal is coupled to microstrip 1105 and travels through PA 1130, where the transmitted signal is amplified and passed to antenna 1102 via microstrip line 1104, where antenna 1102 radiates the transmitted signal. Note that LNA 1120 and PA 1130 are separate electronic components, although they are shown together for convenience in Figures 11A and 11B.

[0100] In this configuration, the radiating portion of the metasurface is isolated from the waveguide 1107, thereby achieving stable high gain. Stability is unconditional because the coupling between the input and output of PA1130 / LNA1120 is significantly reduced. Another advantage of this configuration is that the coupler does not radiate due to the presence of a via (wire) cage 1161 having multiple vias (wires). The via cage 1161 is designed to reduce and potentially avoid interference between radiation from the coupler 1100 and the patch antenna 1102. In some embodiments, the spacing between vias in the via cage 1161 is not greater than the diameter or thickness of the vias themselves.

[0101] Another feature of this structure is its low reflectivity. By creating a cavity-shaped coupler, reflection toward the waveguide during iris transitions can be reduced in the Tx mode. Lower reflection toward the waveguide side results in high efficiency in both Tx and Rx modes. The cavity beneath the patch antenna helps with antenna matching and increases radiation efficiency.

[0102] Due to size limitations, the antenna is electrically small, resulting in low radiation resistance. In some embodiments, electrically small antennas are designed to provide greater possible radiation resistance, thereby increasing efficiency. Since the varactor 1103 is placed after the LNA 1120 in receive (Rx) mode, the noise figure of this configuration is extremely low.

[0103] Figures 12A and 12B show top and side views of several embodiments of modified versions of the unit cell shown in Figures 11A-11C. In this case, the patch antenna is not part of the antenna element. Referring to Figures 12A and 12B, the waveguide 1207 propagates the fed radio waves to the metasurface structure. The metal layer 1210 is coupled to the waveguide 1207 and includes a tunable slot 1206. The substrate 1201 is coupled to the top of the metal layer 1210. Microstrip lines (or other transmission lines) 1204, 1205, and 1216 are coupled to the top of the substrate 1201 and are coupled to the LNA 1220 / PA 1230. Microstrip lines 1204 and 1205 form slots above the tunable slot 1206. Microstrip lines 1204 and 1216 form gaps above the cavity of the cavity back antenna 1202. Microstrip lines 1204 and 1216 are coupled to the metal layer 1210 by via (wire) walls, each having multiple vias (e.g., conductors (e.g., wires)), forming a via cage 1260. The cavity of the cavity back antenna 1202 is formed by the metal layer 1210, the via cage 1260, and the microstrip lines 1204 and 1216. Microstrip lines 1204 and 1205 are coupled to the metal layer 1210 by a via (wire) cage 1261, each having multiple vias (e.g., conductors (e.g., wires)). The via cage 1261 is part of the tuneable coupler 1200. Microstrip lines (or other transmission lines) 1204, 1205, and 1216 are also coupled to the LNA 1220 / PA 1230 using port 1, source (S), and port 2, respectively, to couple to the cavity back antenna 1202. Although shown together in Figures 12A and 12B for convenience, please note that LNA1220 and PA1230 are separate electronic components.

[0104] The metasurface structure includes a tuneable slot 1206 (which is part of the tuneable coupler 1200), a varactor (or another type of tuneable element) 1203 coupled across the tuneable slot 1206, an antenna 1202 having a cavity formed by an LNA 1220 / PA 1230, and a via cage 1260, and a WAIM 1262.

[0105] To reduce costs, in some embodiments, the LNA1220 / PA1230 can be directly connected or coupled to the center of the top layer slot. Although the LNA1220 / PA1230 is shown directly coupled to the center of the cavity back antenna in Figure 12B, this is not mandatory, and its position can be shifted, for example, to change the matching of the LNA1220 / PA1230.

[0106] In some embodiments, in Tx mode (when transmitting a signal), the gate and drain ports of the PA (along with their matching circuits) are connected to port 1 and port 2, respectively. The source (S) is ground. When the open-end slot on top of the coupler 1200 is excited in Tx mode (from the feed propagating from waveguide 1207 through the tuned coupler 1200), a small voltage difference is generated between the gate (port 1) and source (S) of the PA 1230. This voltage is amplified and travels across the slot on the cavity to excite the cavity-back antenna 1202.

[0107] In some embodiments, in Rx mode (when receiving a signal), the gate and drain ports of the LNA 1220 (along with their matching circuits) are connected to or coupled to port 2 and port 1, respectively. The voltage across the cavity back antenna 1202 is amplified with low noise, and the amplified signal is passed across the open-ended slot on top of the coupler 1200. This signal is transmitted through the coupler 1200 to the waveguide 1207. Since the antenna used here is a cavity back antenna, there is no back radiation into the waveguide 1207. This significantly reduces reflection losses, which are advantageous when the gain of the LNA 1220 is high.

[0108] Although not shown in Figures 12A and 12B, note that in some embodiments, the gate (G) is coupled to the input or otherwise represents the input, the drain (D) is coupled to the output or otherwise represents the output, and the source (S) is coupled to a common ground plane. An example of this arrangement is shown in Figures 14A and 14B, which are described in more detail below.

[0109] Figures 13A and 13B show side and top views of radiating antenna elements in several embodiments in which a varactor is integrated into the LNA / PA for further cost reduction. Referring to Figures 13A and 13B, the waveguide 1307 propagates the fed radio waves to the metasurface structure. The metal layer 1310 is coupled to the waveguide 1307 and includes a tunable slot 1306. The substrate 1301 is coupled to the top of the metal layer 1310. Microstrip lines (or other transmission lines) 1304, 1305, and 1316 are coupled to the top of the substrate 1301 and are coupled to the LNA 1320 / PA 1330. Microstrip lines 1304 and 1305 form slots above the tunable slot 1106. Microstrip lines 1304 and 1316 form gaps above the cavity of the cavity-back antenna 1302. Microstrip lines 1304 and 1316 are coupled to the metal layer 1310 by via (wire) walls, each having multiple vias (conductors (e.g., wires)), forming a via cage 1360. The cavity of the cavity back antenna 1302 is formed by the metal layer 1310, the via cage 1360, and the microstrip lines 1304 and 1316. Microstrip lines 1304 and 1305 are coupled to the metal layer 1310 by a via (wire) cage 1361, each having multiple vias (conductors (e.g., wires)). The via cage 1361 is part of the tuneable coupler 1300. Microstrip lines (or other transmission lines) 1304, 1305, and 1316 are also coupled to the LNA 1320 / PA 1330 using port 1, source(s), and port 2, respectively, to couple to the cavity back antenna 1302.

[0110] The metasurface structure includes a tunable slot 1306 (which is part of the tunable coupler 1300), a varactor (or another type of tunable element) 1303 coupled across the tunable slot 1306, an LNA 1320 / PA 1330, an antenna 1302 having a cavity formed by a via cage 1360, and a WAIM 1362. For convenience, they are shown together in Figures 13A and 13B, but it should be noted that the LNA 1320 and PA 1330 are separate electronic components in some embodiments. In some embodiments of this configuration (as opposed to the configurations in Figures 12A and 12B), the radiating antenna element / unit cell operates as a radiating antenna element / unit cell in which the varactor 1303 still tunes the reactance across the tunable slot (iris) 1306. In some embodiments, the varactor 1303 and LNA1320 / PA1330 can be designed together on a single die to reduce their size and lower cost. This also reduces losses, increases efficiency, and improves the noise figure (in Rx). This configuration is cost-effective because the LNA1320 / PA1330 and varactor 1303 are designed on an integrated PCB (substrate 1301). Furthermore, the cavity-back antenna 1302 operates so that radiation is not radiated backward, resulting in extremely low reflection losses.

[0111] Figures 14A and 14B are block diagrams of several embodiments of a single-dia varactor that can be used in a metasurface configuration (e.g., Figures 13A and 13B). Referring to Figures 14A and 14B, the varactor 1410 is integrated between the gate and source of the power amplifier 1411 in Tx mode and between the drain and source of the low-noise amplifier 1433 in Rx mode. By integrating these two components, significant cost reductions are possible. In some embodiments, the varactor 1410 comprises a variable P-cell 1410A (e.g., a PIN diode, pn junction) and a MIM (metal-insulator-metal) capacitor 1410B.

[0112] Accordingly, embodiments of active metasurfaces having low reflection loss described herein may have one or more of the following advantages: extremely low reflection loss, low noise figure and moderate to high gain at Rx, high gain with unconditional stability at Tx, high efficiency, high tuning, and compatibility with PCB design processes for low-cost design.

[0113] There are several exemplary embodiments described herein.

[0114] Embodiment 1 is an antenna comprising a metasurface having a plurality of tuneable radiating antenna elements. Each of the tuneable radiating antenna elements includes a gap, a pair of conductors arranged in the gap, a transistor coupled to the pair of conductors, a tuning element configured to tune each of the tuneable radiating antenna elements, a capacitor coupled in series with the tuning element, and an amplifier coupled in parallel with the tuning element and the capacitor, wherein the first terminals of the tuning element and the amplifier are coupled to the first terminals of the transistor and the capacitor, and the output terminal of the amplifier is coupled to the second terminal of the transistor.

[0115] Example 2 is the antenna of Example 1, which optionally includes the configuration where the plurality of tuneable radiating antenna elements within the metasurface are single-layered.

[0116] Example 3 is the antenna of Example 1, in which the gap may optionally include a slot.

[0117] Embodiment 4 is the antenna of Embodiment 3, in which the above-mentioned slots can optionally include a folding slot.

[0118] Embodiment 5 is the antenna of Embodiment 4, which optionally includes the fact that the transistor is a field-effect transistor (FET) having a gate, source, and drain, the gate and drain are coupled to both sides of the slot, and the source is coupled to a pair of conductors in the folded slot.

[0119] Embodiment 6 is an antenna of Embodiment 4, which optionally includes the following: the transistor is a bipolar junction transistor (BJT) having a base, emitter, and collector, the base and collector are coupled to both sides of the slot, and the emitter is coupled to a pair of conductors in the folded slot.

[0120] Example 7 is an antenna of Example 1, which optionally includes the tuning element including a varactor, the capacitor including an MIM capacitor, and the tuning element, the capacitor, and the amplifier being part of a single die.

[0121] Example 8 is the antenna of Example 1, which optionally includes a capacitor that is an MIM capacitor.

[0122] Example 9 is an antenna of Example 1, which optionally includes the tuning element, capacitor, and amplifier being part of a single die.

[0123] Example 10 is an antenna of Example 9, which optionally includes a slot having length and width, and a single die being coupled across the width of the slot in a central portion along its length.

[0124] Example 11 is an antenna of Example 9, which optionally includes a slot having length and width, and a single die being coupled across its width at a position offset from the central portion of its length.

[0125] Example 12 is an antenna comprising a metasurface having a plurality of tuneable radiating antenna elements. Each tuneable radiating antenna element includes a folding slot, a first and second pair of conductors arranged within the slot, with a gap in the slot between the first and second pairs of conductors, a first transistor coupled to the first pair of conductors, a second transistor coupled to the second pair of conductors, and a first die coupled to the first transistor across the first slot, wherein the first die includes a first tuning element configured to tune each tuneable radiating antenna element, a first capacitor coupled in series with the first tuning element, and a first amplifier coupled in parallel with the first tuning element and the first capacitor, and includes a second die coupled to the second transistor across the first slot, wherein the second die includes a second tuning element for tuning each tuneable radiating antenna element, a second capacitor coupled in series with the second tuning element, and a second amplifier coupled in parallel with the second tuning element and the second capacitor.

[0126] Example 13 is an antenna of Example 12, which optionally includes a first transistor being a field-effect transistor (FET) having a first gate, a first source, and a first drain, wherein the first gate and the first drain are coupled on opposite sides of the slot and the first source is coupled to a first pair of conductors in the folding slot, and a second transistor being an FET having a second gate, a second source, and a second drain, wherein the second gate and the second drain are coupled on opposite sides of the slot and the second source is coupled to a second pair of conductors in the folding slot.

[0127] Embodiment 14 is an antenna of Embodiment 13, which optionally includes a first amplifier having a first input and a first output coupled to the first gate and first drain of a first transistor, respectively, and a second amplifier having a second input and a second output coupled to the second gate and second drain of a second transistor, respectively.

[0128] Embodiment 15 is an antenna of Embodiment 12 in which the first and second transistors are bipolar junction transistors (BJTs), the first transistor comprising a bipolar junction transistor (BJT) having a first base, a first emitter, and a first collector, the first base and the first collector coupled on opposite sides of the slot, and the first emitter coupled to a first pair of conductors of the folding slot, and optionally further comprising a second transistor comprising a BJT having a second base, a second emitter, and a second collector, the second base and the second collector coupled on opposite sides of the slot, and the second emitter coupled to a second pair of conductors of the folding slot.

[0129] Embodiment 16 is an antenna comprising a metasurface having radiating antenna elements and an amplifier configured to amplify signals for the radiating antenna elements. For each radiating antenna element, the metasurface includes an antenna element and at least one of the following: a low-noise amplifier (LNA) coupled to a patch antenna and configured to amplify the signal received by the patch antenna of each radiating antenna element; a power amplifier (PA) coupled to a patch antenna and configured to amplify the signal for transmission from one radiating antenna element by the patch antenna; and a tuneable coupler coupled to the patch antenna using a wire cage. The coupler includes a tuneable slot for coupling a feed to each radiating antenna element and a tuning element coupled to the tuneable slot to tune the tuneable slot.

[0130] Example 17 is an antenna of Example 16, which optionally includes a wire cage comprising a via cage having multiple vias.

[0131] Example 18 is the antenna of Example 16, which optionally includes the antenna element being electrically short-circuited to the ground plane.

[0132] Example 19 is an antenna of Example 18, which optionally includes the antenna element being electrically short-circuited to the ground plane using a second set of vias.

[0133] Example 20 is an antenna of Example 16, which optionally includes a first plurality of vias traversing the substrate and coupled to a first side of a conductive layer including slots and to one or more transmission lines, the conductive layer being coupled to one side of the substrate, and one or more transmission lines being coupled to a second side of the substrate opposite the first side of the substrate.

[0134] Example 21 is an antenna of Example 20, which optionally includes the coupling of a tuning element across a slot on the second side of the conductive layer opposite to the first side of the conductive layer.

[0135] Embodiment 22 is an antenna of Embodiment 20, which optionally includes a tuning element located on a second side surface of the substrate and coupled to at least one of one or more transmission lines at positions above and across the slots.

[0136] Example 23 is an antenna of Example 22, which optionally includes the coupling of a tuning element to a conductive layer using vias within a wire cage.

[0137] Example 24 is an antenna of Example 20, which optionally includes the conductive layer being a ground layer.

[0138] Example 25 is an antenna of Example 16, which optionally includes a varactor as a tuning element.

[0139] Example 26 is the antenna of Example 25, which optionally includes the coupling of the LNA between the varactor and the patch antenna.

[0140] Example 27 is an antenna of Example 26, optionally including that the varactor is located in the die together with either or both the LNA and PA.

[0141] Example 28 is an antenna comprising a metasurface having a plurality of radiating antenna elements. Each of the plurality of radiating antenna elements comprises: a cavity back antenna; at least one of a low-noise amplifier (LNA) coupled to the cavity back antenna and configured to amplify the signal received by the cavity back antenna of each radiating antenna element, and a power amplifier (PA) coupled to the cavity back antenna and configured to amplify the signal for transmission from one radiating antenna element by the cavity back antenna; and a tuneable coupler coupled to the cavity back antenna using a first wire cage having a first plurality of vias. The tuneable coupler includes a tuneable slot for coupling a feed to each radiating antenna element, and a tuning element coupled to the tuneable slot for tuning the tuneable slot.

[0142] Example 29 is an antenna of Example 28, which optionally includes the first wire cage containing a plurality of vias.

[0143] Example 30 is an antenna of Example 28, which optionally includes a cavity back antenna having a cavity formed by a second wire cage.

[0144] Example 31 is an antenna of Example 30, which optionally includes a second wire cage containing multiple vias.

[0145] Embodiment 32 is an antenna of Embodiment 28, which optionally includes a first plurality of vias traversing the substrate, coupling one or more transmission lines to a first side of a conductive layer including slots, the conductive layer being coupled to one side of the substrate, one or more transmission lines being coupled to a second side of the substrate opposite to the first side of the substrate, and a tuning element being coupled across slots on the second side of the conductive layer opposite to the first side of the conductive layer.

[0146] Example 33 is an antenna of Example 32, which optionally includes a first plurality of vias traversing the substrate, coupling a first side of a conductive layer containing slots to one or more transmission lines, the conductive layer being coupled to one side of the substrate, one or more transmission lines being coupled to a second side of the substrate opposite to the first side of the substrate, and one or both of the LNA and PA being located on the second side of the substrate and connected to at least one of the one or more transmission lines at a position spanning the slots above the slots.

[0147] Embodiment 34 is an antenna of Embodiment 33, which optionally includes the tuning element being located on one or both of the LNA and PA, on the second side of the substrate, and in a position spanning the slots.

[0148] Example 35 is an antenna of Example 28, which optionally includes a varactor as a tuning element.

[0149] Example 36 is an antenna of Example 35, which optionally includes a varactor that includes a tunable P-cell and is coupled to a capacitor.

[0150] Example 37 is an antenna of Example 28, which optionally includes a metal-insulator-metal (MIM) capacitor.

[0151] The methods and tasks described herein can be performed by a computer system and can be fully automated. In some cases, the computer system may include multiple separate computers or computing devices (e.g., physical servers, workstations, storage arrays, cloud computing resources, etc.) that communicate and interoperate over a network to perform the functions described. Each such computing device typically includes a processor (or more processors) that executes program instructions or modules stored in memory or other non-temporary computer-readable storage media or devices (e.g., solid-state storage devices, disk drives, etc.). The various functions disclosed herein may be embodied in such program instructions or implemented in application-specific circuits (e.g., ASICs or FPGAs) of the computer system. If the computer system includes multiple computing devices, these devices may, but are not required, be in the same location. The results of the disclosed methods and tasks can be permanently stored by converting a physical storage device, such as a solid-state memory chip or magnetic disk, into different states. In some embodiments, the computer system may be a cloud-based computing system in which processing resources are shared by multiple different business entities or other users.

[0152] Depending on the embodiment, certain operations, events, or functions of any of the processes or algorithms described herein may be performed in different sequences, added, integrated, or excluded together (for example, not all of the described operations or events are necessary for the implementation of the algorithm). Furthermore, in certain embodiments, the operations or events may be performed simultaneously, for example, not sequentially, but through multithreaded processing, interrupt processing, or by multiple processors or processor cores or other parallel architectures.

[0153] The various exemplary logic blocks, modules, routines, and algorithmic steps described in the embodiments disclosed herein can be implemented as electronic hardware (e.g., ASIC or FPGA devices), computer software running on computer hardware, or a combination of both. Furthermore, the various illustrative logic blocks and modules described with respect to the embodiments disclosed herein can be implemented or executed by machines such as processor devices, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. The processor device may be a microprocessor, but alternatively, the processor device may be a controller, microcontroller, or state machine, or a combination thereof. The processor device may include electronic circuits configured to process computer-executable instructions. In another embodiment, the processor device includes an FPGA or other programmable device that performs logic operations without processing computer-executable instructions. Processor devices can also be implemented as a combination of computer devices, for example, as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors working in conjunction with a DSP core, or any other such configuration. Although this specification has primarily described digital technologies, processor devices may also include primarily analog components. For example, some or all of the technologies described herein can be implemented in analog circuits or mixed analog and digital circuits. Computing environments can include, but are not limited to, any type of computer system, including, for example, a microprocessor, a mainframe computer, a digital signal processor, a portable computing device, a device controller, or a computer system based on a computer engine within a device.

[0154] Elements of methods, processes, routines, or algorithms described in relation to embodiments disclosed herein may be implemented directly in hardware, in software modules executed by a processor device, or a combination of both. The software modules may reside in any other form of RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disks, removable disks, CD-ROMs, or non-temporary computer-readable storage media. An exemplary storage medium may be coupled to the processor device so that the processor device can read information from and write information to the storage medium. Alternatively, the storage medium may be integrated with the processor device. The processor device and storage medium may reside in an ASIC. The ASIC may reside in a user terminal. Alternatively, the processor device and storage medium may reside as discrete components of a user terminal.

[0155] In particular, conditional expressions used herein, such as “can,” “could,” “might,” “may,” and “eg,” generally convey that a particular embodiment includes certain features, elements, or steps, and other embodiments do not, unless otherwise explicitly indicated or understood in the context in which they are used. Therefore, such conditional expressions generally do not imply that features, elements, or steps are required to some extent in one or more embodiments, or that there is a logic determining whether these features, elements, or steps are included in or should be performed in any particular embodiment, based on the presence or absence of other inputs or instructions. Words such as “comprising,” “including,” and “having” are synonymous and used in an inclusive, unrestricted manner, not excluding additional elements, features, actions, or operations. Furthermore, the word "or," when used, for example, is used to connect a list of elements, and the word "or" is used in an inclusive sense (not exclusive) to mean one, some, or all of the elements in the list.

[0156] Disjunctive expressions such as "at least one of X, Y, or Z" are generally understood in contexts where they are commonly used to indicate that an item, term, etc., can be any of X, Y, or Z, or any combination thereof (e.g., X, Y, or Z), unless otherwise explicitly indicated. Therefore, such disjunctive expressions are generally not intended, and should not be intended, to require that a particular embodiment must each contain at least one X, at least one Y, and at least one Z.

[0157] The above detailed description illustrates, describes, and points out new features that may be added to various embodiments, and it is understood that various omissions, substitutions, and modifications in the form and details of the illustrated devices or algorithms may be made without departing from the spirit of this disclosure. As is recognizable, some features may be used or carried out separately from others, so that certain embodiments described herein may be carried out in a form that does not provide all of the features and benefits shown herein. The scope of the specific embodiments disclosed herein is indicated not by the above specification but by the appended claims. All modifications that occur within the meaning and scope of the equivalents of the claims shall be incorporated within those scopes. [Explanation of Symbols]

[0158] 301 slots 301A, 301B Conductor - Foldable 302 Conductors (e.g., copper) 303 Die 305 Transistor Drain 306 Transistor Source 307 Transistor Gate

Claims

1. It is an antenna, A metasurface having multiple tunable radiating antenna elements, Each of the aforementioned tunable radiating antenna elements is The gap, A pair of conductors arranged within the gap, A transistor coupled to the aforementioned pair of conductors, A tuning element configured to tune each of the aforementioned tunable radiating antenna elements, A capacitor coupled in series with the aforementioned tuning element, An amplifier coupled in parallel to the aforementioned tuning element and the aforementioned capacitor, Includes, An antenna in which the tuning element and the first terminal of the amplifier are coupled to the first terminals of the transistor and the capacitor, and the output terminal of the amplifier is coupled to the second terminal of the transistor.

2. The antenna according to claim 1, wherein the plurality of tuneable radiating antenna elements within the metasurface are single-layered.

3. The antenna according to claim 1, wherein the gap includes a slot.

4. The antenna according to claim 3, wherein the slot includes a folding slot.

5. The antenna according to claim 4, wherein the transistor is a field-effect transistor (FET) having a gate, a source, and a drain, the gate and drain being coupled to both sides of the slot, and the source being coupled to a pair of conductors of the folding slot.

6. The antenna according to claim 4, wherein the transistor is a bipolar junction transistor (BJT) having a base, an emitter, and a collector, the base and collector being coupled to both sides of the slot, and the emitter being coupled to a pair of conductors of the folding slot.

7. The antenna according to claim 1, wherein the tuning element includes a varactor, the capacitor includes an MIM capacitor, and the tuning element, the capacitor and the amplifier are part of a single die.

8. It is an antenna, A metasurface comprising a radiating antenna element and an amplifier configured to amplify the signal from the radiating antenna element, For each of the aforementioned radiating antenna elements, the metasurface is Antenna element and below; A low-noise amplifier (LNA) coupled to a patch antenna and configured to amplify the signal received by the patch antenna for each of the radiating antenna elements, A power amplifier (PA) coupled to the patch antenna and configured to amplify the signal transmitted from one of the radiating antenna elements by the patch antenna, At least one of the following, A tuneable coupler coupled to the patch antenna using a wire cage, Includes, The aforementioned coupler, Each of the aforementioned radiating antenna elements is provided with a tunable slot for coupling the fed radio waves, A tuning element coupled to the aforementioned tunable slot to tune the aforementioned tunable slot, Antennas, including

9. The antenna according to claim 8, wherein the wire cage includes a via cage having a plurality of vias.

10. The antenna according to claim 8, wherein the antenna element is electrically short-circuited to the ground plane.

11. The antenna according to claim 10, wherein the antenna element is electrically short-circuited to a ground plane using a second plurality of vias.

12. The antenna according to claim 8, wherein the first plurality of vias traverse the substrate and are coupled to a first side of a conductive layer including the slots and to one or more transmission lines, the conductive layer is coupled to one side of the substrate, and the one or more transmission lines are coupled to a second side of the substrate opposite to the first side of the substrate.

13. The antenna according to claim 12, wherein the tuning element is coupled across the slot on the second side of the conductive layer, which is opposite to the first side of the conductive layer.

14. The antenna according to claim 12, wherein the tuning element is located on the second side surface of the substrate and is coupled to at least one of the one or more transmission lines at a position above and across the slot.

15. The antenna according to claim 14, wherein the tuning element is coupled to the conductive layer using vias in the wire cage.

16. It is an antenna, A metasurface having multiple radiating antenna elements, Each of the plurality of radiating antenna elements is Cavity back antenna and below: A low-noise amplifier (LNA) coupled to the cavity back antenna and configured to amplify the signals received by the cavity back antenna from each of the radiating antenna elements, A power amplifier (PA) coupled to the cavity back antenna and configured to amplify the signal for transmission from one of the radiating antenna elements by the cavity back antenna, At least one of the following, A tuneable coupler coupled to the cavity back antenna using a first wire cage having a first plurality of vias, Includes, The aforementioned coupler is, Each of the aforementioned radiating antenna elements is provided with a tunable slot for coupling the fed radio waves, A tuning element coupled to the tuning slot in order to tune the tuning slot, Antennas, including

17. The antenna according to claim 16, wherein the first wire cage includes a plurality of vias.

18. The antenna according to claim 16, wherein the cavity back antenna includes a cavity formed by a second wire cage.

19. The antenna according to claim 18, wherein the second wire cage includes a plurality of vias.

20. A first plurality of vias traverse the substrate, and a first side of the conductive layer including the slots is coupled to one or more transmission lines, the conductive layer is coupled to one side of the substrate, and the one or more transmission lines are coupled to a second side of the substrate opposite to the first side of the substrate. The antenna according to claim 16, further comprising the tuning element coupled across the slot to the second side of the conductive layer opposite to the first side of the conductive layer.

21. The antenna according to claim 20, wherein a first plurality of vias traverse the substrate, coupling a first side of a conductive layer including the slots to one or more transmission lines, the conductive layer is coupled to one side of the substrate, the one or more transmission lines are coupled to a second side of the substrate opposite to the first side of the substrate, and one or both of the LNA and PA are located on the second side of the substrate and connected to at least one of the one or more transmission lines at a position over and across the slots.

22. The antenna according to claim 21, wherein the tuning element is located on one or both of the LNA and the PA, on the second side of the substrate and across the slot.

Images