Systems and methods for designing, optimizing, patterning, forming, and manufacturing symphotic structures are described herein. A symphotic structure may be formed by identifying a continuous refractive index distribution calculated to convert each of a plurality of input reference waves to a corresponding plurality of output object waves. The continuous refractive index distribution can be modeled as a plurality of subwavelength voxels. The system can calculate a symphotic pattern as a three-dimensional array of discrete dipole values to functionally approximate the subwavelength voxels. A symphotic structure may be formed with a volumetric distribution of dipole structures. A dipole value, such as a dipole moment (direction and magnitude) of each dipole is selected for the volumetric distribution to convert a plurality of input reference waves to a target plurality of output object waves.

An antenna architecture comprises a hybrid beamformer comprising on the one hand, Ny stacked quasi-optical beamformers, each quasi-optical beamformer comprising a parallel-plate waveguide furnished with a linear radiating aperture and integrating a lens and internal horns furnished with beam access ports, each quasi-optical beamformer forming beams in two, transmission and reception, frequency bands, in a first direction in space, and on the other hand, at least one electronic beamformer comprising a combining device linked to Nx phase and amplitude control chains, each phase and amplitude control chain being connected to a respective beam access port of each quasi-optical beamformer, the electronic beamformer forming beams in a second direction in space, orthogonal to the first direction.

Receiving antenna (1) for terahertz radiation (30), comprising an antenna conductor (2) and a first photoconductor (3) connected to the antenna conductor (2) and activatable by light (9), the first photoconductor (3) allowing, in an activated state, an antenna current (28) flowing through the antenna conductor (2) and the first photoconductor (3), characterized in that the receiving antenna (1) comprises at least one second photoconductor (4) connected to the antenna conductor (2) and activatable by light (9), the second photoconductor connected in parallel with the first photoconductor (3) and, in an activated state, allowing an antenna current (28) flowing through the antenna conductor (2) and the second photoconductor (4), wherein at least one respective high-pass filter (8) is connected between each of the photoconductors (3, 4) and the antenna conductor (2). The invention further relates to a receiver for terahertz radiation (30), a terahertz system, and a method for generating and detecting terahertz radiation (30) using such a terahertz system.

A reconfigurable antenna comprises a plurality of antenna feed elements, a plurality of plasma switches respectively associated with the antenna feed elements, and control circuitry for independently operating the plasma switches to selectively activate and deactivate the antenna feed elements. Each plasma switch may comprise a volume of inert gas, and a pair of electrodes spanning the respective volume of inert gas. The reconfigurable antenna may comprise a power supply for supplying a voltage to the pair of electrodes of each of plasma switch sufficient to ignite the respective inert gas volume into a plasma field to deactivate the respective antenna feed element. Each plasma switch may optionally be operated to attenuate each antenna feed element.

A split ring resonator (10) as a unit cell of a passive element includes a conductor (1) made of a metal and having an annular shape split by a first gap (2) and a second gap (3) different from the first gap (2). A first capacitance generated by the first gap (2) is different from a second capacitance generated by the second gap (3).

A system includes a phased array antenna. The phased array antenna includes a rear panel that has: a first array of phase shift elements; and a second array of rear antenna elements. The phased array antenna also includes a front panel that has a third array of front antenna elements. Each of the front antenna elements is electrically coupled to a corresponding one of the rear antenna elements through one of the phase shift elements. When the second array of rear antenna elements receives a radio signal from a base station and the first array of phase shift elements receives an optical control beam from the base station, the third array of antenna elements radiates an output radio signal in a direction indicated by the optical control beam.

Techniques related to a 5.sup.th generation (5G) or pre-5G communication system to support higher data rates after a 4.sup.th generation (4G) communication system such as long term evolution (LTE) ae provided. A reflector is provided that is configured to change a direction of a beam incident in a first direction to a second direction different from the first direction, so that a receiving entity positioned in a shadow area caused by an object can receive the beam. Therefore, the reflector removes the shadow area at which the beam does not arrive in a 5G wireless communication system.

A multi-level antenna array includes a plurality of patch antennas. Each layer of a plurality of layers is separated from other layers by a distance and support a portion of the plurality of patch antennas. Each of a plurality of connectors is associated with one of the plurality of layers for supplying a signal for transmission by the associated layer. A feed network on each of the plurality of layers provides a connection between a connector of the plurality of connectors associated with the layer and the portion of the plurality of patch antennas located on the layer. Each layer of the plurality of layers transmits the signal having a different orthogonal function applied thereto and multiplexes each of the signals having the different orthogonal function applied thereto onto a single transmission beam.

A reconfigurable antenna comprises a plurality of antenna feed elements, a plurality of plasma switches respectively associated with the antenna feed elements, and control circuitry for independently operating the plasma switches to selectively activate and deactivate the antenna feed elements. Each plasma switch may comprise a volume of inert gas, and a pair of electrodes spanning the respective volume of inert gas. The reconfigurable antenna may comprise a power supply for supplying a voltage to the pair of electrodes of each of plasma switch sufficient to ignite the respective inert gas volume into a plasma field to deactivate the respective antenna feed element. Each plasma switch may optionally be operated to attenuate each antenna feed element.

A multi-level antenna array includes a plurality of patch antennas. Each layer of a plurality of layers is separated from other layers by a distance and support a portion of the plurality of patch antennas. Each of a plurality of connectors is associated with one of the plurality of layers for supplying a signal for transmission by the associated layer. A feed network on each of the plurality of layers provides a connection between a connector of the plurality of connectors associated with the layer and the portion of the plurality of patch antennas located on the layer. Each layer of the plurality of layers transmits the signal having a different orthogonal function applied thereto and multiplexes each of the signals having the different orthogonal function applied thereto onto a single transmission beam.