A method and apparatus for using Euclidean modulation in an antenna are disclosed. In one embodiment, a method for controlling an antenna comprises mapping a desired modulation to achievable modulation states, mapping modulation values associated with the achievable modulation states to one or more control parameters, and controlling radio frequency (RF) radiating antenna elements using the one or more control parameters to perform beam forming.

A resonant wearable antenna system includes a ground plane and an antenna structure positioned over the ground plane. The ground plane includes a first cloth substrate and an array of metamaterial (MTM) unit cells positioned on the substrate. At least one MTM unit cell includes four four-leaf-clover units arranged in a four-leaf-clover pattern and connected to a center unit. Each four-leaf-clover unit includes four leaf units arranged in a four-leaf-clover pattern and connected to a subcenter unit. The antenna structure includes a second cloth substrate and a conductive pattern positioned over the second cloth substrate. The antenna structure is configured to have a first resonant frequency below 1 GHz and a second resonant frequency higher than the first resonant frequency. The array of MTM unit cells is configured to reflect incident waves, from the antenna structure at the first resonant frequency and the second resonant frequency, in-phase.

A versatile metamaterial reflector is constructed of at least one pair of first and second reflectors each having a frequency-dependent phase shifting of a reflected waveform but together providing, between them, a constant phase difference. As few as two different types of reflectors (for example, a zero and relative pi radian reflector) are used to construct a variety of metamaterial reflectors.

A detection device (DD) is fitted in a system (S) comprising a closed space (EF) with a metallic environment and comprising objects (O) provided with wave-transmitting/receiving identification elements. Said device (DD) comprises an identification reader (LI) which exchanges messages with the identification elements (EI) via a wave-transmitting/receiving antenna (AER), which reader is installed inside the closed space (EF), in order to detect the presence of said waves, and a metasurface (MS1) installed inside the closed space (EF) and configured so as to reflect, according to a first chosen law, waves which originate from the antenna (AER) and are intended for the identification elements (EI) and, according to a second chosen law, waves which originate from the identification elements (EI) and are intended for the antenna (AER).

A system for EMNZ metamaterial-based direct antenna modulation. The system includes a signal generator, a metamaterial switch and an antenna. The signal generator may is configured to generate a microwave signal. The metamaterial switch is configured to generate a modulated microwave signal from the microwave signal. The modulated microwave signal is generated by selectively passing the microwave signal through the metamaterial switch. The metamaterial switch includes a first conductive plate and a first loaded conductive plate. The first loaded conductive plate includes a second conductive plate and a first monolayer graphene. The first monolayer graphene includes a first tunable conductivity. The first monolayer graphene is positioned between the first conductive plate and the second conductive plate. An effective permittivity of the metamaterial switch is configured to be adjusted to a predetermined value. The effective permittivity of the metamaterial switch is adjusted responsive to tuning the first tunable conductivity.

A body part for a motorized land vehicle is provided. The body part includes at least one wall made of a plastic material and including at least one housing forming a cavity for electromagnetic waves, said housing includes: at least one transceiver for transmitting and/or receiving an electromagnetic wave in said housing; at least one adaptable surface capable of reflecting the electromagnetic wave transmitted by the transceiver in a given direction (in a controlled manner) and, conversely, capable of reflecting the electromagnetic wave coming from the exterior of the housing toward the transceiver.

Antennas with tunable elements and methods for using the same are disclosed. In some embodiments, an antenna comprises: a plurality of radio-frequency (RF) radiating antenna elements, wherein each antenna element of the plurality of RF radiating antenna elements comprises a tunable element, circuitry connected to the tuning element to set a voltage on the tunable element. In some embodiments, the circuitry comprises a voltage storage structure, a first transistor having a first gate connected to the voltage storage structure, a first source connected to the tunable element, and a first drain for coupling to a constant voltage source, and a data voltage input terminal operable to apply a voltage to the voltage storage structure and to the first gate to determine current through the first transistor.

Methods and apparatuses for performing optical inspection of varactor diodes in an antenna are disclosed. In some embodiments, the method of testing an antenna having varactor diodes comprises: selecting a plurality of varactor diodes to be placed in a light emitting state; forward biasing the selected varactor diodes to a magnitude at which the selected varactor diodes are to emit light; and detecting one or more faulty varactor diodes of the selected varactor diodes based on their emitted light intensity.

According to various embodiments, a tunable optical device comprises a tunable optical metasurface on a substrate with an integrated driver circuit. In some embodiments, the tunable optical device includes a photon shield layer to prevent optical radiation from disrupting operation of the driver circuit. In some embodiments, the tunable optical device includes a diagnostic circuit to detect and disable defective optical structures of the metasurface. In some embodiments, the tunable optical device includes an integrated heater circuit that maintains a liquid crystal of the metasurface above a minimum operating temperature. In some embodiments, the tunable optical device includes an integrated lidar sequencing controller, a steering pattern subcircuit, and a photodetector circuit.

Disclosed are an active complex spatial light modulation method and apparatus for an ultra-low noise holographic display. The active complex spatial light modulation apparatus includes a substrate and a petal antenna including three petal patterns arranged on the substrate, dividing a complex plane into three phase sections, and modulating the input light into three-phase amplitude values corresponding to the phase sections. The petal antenna may have a point symmetry shape based on the center point of the petal antenna.