A coherent imaging system including a transmitter and a receiver. The transmitter includes a coherent source and a power splitter for splitting the electromagnetic radiation into a reference and a signal beam. The receiver includes an image forming device and an array of pixels. Each of the pixels include means for collecting at least a portion of the signal beam imaged on the pixel by an image forming device, as a collected signal; means for splitting the collected signal into a plurality of collected signals each having different phase shifts; means for mixing each of the collected signals with the reference beam so as to form a plurality of mixed signals; and means for detecting the mixed signals and outputting a plurality of output electrical signals in response to the mixed signals.

A method for constructing a multifunctional antenna structure configured to generate a plurality of radiation patterns includes determining a desired source field associated with the plurality of radiation patterns, and receiving feed locations for a waveguide to an antenna aperture surface. The method may further include placing a metasurface resonator at a first resonator location that exhibits a minimum error relative to the desired source field and satisfies a maximum error threshold relative to the desired source field. The metasurface resonator may be determined based on the feed locations and a plurality of degrees of freedom for the first resonator location. The method may also include discarding a second resonator location in response to determining that no metasurface resonator at the second resonator location satisfies the maximum error threshold. The plurality of degrees of freedom may include metasurface resonator geometries that exhibit different polarizabilities defined in a candidate library.

A structure includes: a base that includes a first surface and a second surface parallel to a first plane, a third surface and a fourth surface parallel to a second plane orthogonal to the first plane, and a fifth surface and a sixth surface parallel to a third plane orthogonal to the first plane and the second plane; a first conductor that expands along the third plane and that extends along a second direction; a second conductor that expands along the fourth plane and that extends along the second direction; a third conductor that expands along the first plane and that is configured to capacitively connect the first conductor and the second conductor; and a fourth conductor that is configured to be electrically connected to the first conductor and the second conductor. The first conductor, the second conductor, and the third conductor are at least partially exposed to exterior space.

An attachable booster antenna attachable to a coil antenna, includes a body; and an antenna including a multiple resonant antennas arrayed on the body, with each resonant antenna including an insulator layer having first and second surfaces; and first and second loop antennas disposed on the first and second surfaces, respectively, so as to confront each other via the insulator layer. Moreover, the first and second loop antennas each having an opening that discontinue a part of a loop and are arranged such that a closed loop is defined by at least a part of the first loop antenna and at least a part of the second loop antenna in a transparent plane viewed from a normal direction of the insulator layer. Furthermore, in the plan view of the insulator layer, the opening of the first and second loop antennas and the opening of the coil antenna overlap each other.

Disclosed herein is an antenna device that includes a filter layer, an antenna layer, a divider layer, and ground patterns. The antenna layer has first and second radiation conductors and first and second ground pillars that surround the first and second radiation conductors, respectively. Each of the first and second ground patterns has a first area that overlaps a first space surrounded by the first ground pillars, a second area that overlaps a second space surrounded by the plurality of second ground pillars, and a third area that connects the first and second areas. A width of the third area in a width direction perpendicular to an arrangement direction of the first and second areas is smaller than a width of each of the first and second areas in the width direction.

A distributed antenna system comprises: one or more access units configured to receive multiple downlink radio frequency signal sets, and further configured to convert the multiple downlink radio frequency signal sets into multiple downlink optical signal sets; a first wavelength division multiplexing unit configured to multiplex the multiple downlink optical signal sets to generate a first wavelength division multiplexing optical signals; a first wavelength division demultiplexing unit configured to demultiplex the first wavelength division multiplexing optical signals to obtain the multiple downlink optical signal sets; a first optical fiber, coupled between the first wavelength division multiplexing unit and the first wavelength division demultiplexing unit, and configured to transmit the first wavelength division multiplexing optical signal; and multiple first remote units coupled to the first wavelength division multiplexing unit, and configured to convert the multiple downlink optical signal sets into the multiple downlink radio frequency signal sets for transmission.

Examples disclosed herein relate to a radiating structure. The radiating structure has a transmission array structure having a plurality of transmission paths with each transmission path having a plurality of slots and a pair of adjacent transmission paths forming a superelement. Each superelement has a phase control module to control a phase of a transmission signal. The radiating structure also includes a radiating array structure having a plurality of radiating elements configured in a lattice, with each radiating element corresponding to at least one slot from the plurality of slots and the radiating array structure positioned proximate the transmission array structure. A feed coupling structure is coupled to the transmission array structure and adapted for propagation of a transmission signal to the transmission array structure. The transmission signal is radiated through at least one superelement and at least one of the plurality of radiating elements and has a phase controlled by the phase control module in the at least one superelement.

The disclosed structures and methods are directed to antenna systems configured to transmit and receive a wireless signal in and from different directions. A switchable lens antenna has excitation ports radiating radio-frequency (RF) wave into a parallel-plate waveguide structure, and a frequency selective structure (FSS). The antenna presented herein is configured to operate in two modes depending on an initial steering angle of the RF wave propagating in the parallel-plate waveguide structure. When the initial steering angle is about or less than a threshold steering angle, FSS is OFF due to its stubs being electrically disconnected from the parallel-plate waveguide structure. When the initial steering angle is higher than the threshold, FSS is ON with stubs being electrically connected to the parallel-plate waveguide structure. When ON, FSS provides phase variance to the RF wave propagating in the parallel-plate waveguide structure and increases steering angle of the RF wave.

In some examples, an antenna system includes a source antenna and a frequency selective surface (FSS) comprising a first section including a first set of horizontally oriented unit cells, a second section including a second set of horizontally oriented unit cells, and a third section between the first section and the second section, the third section including a set of vertically oriented unit cells, wherein the first section is substantially square in shape, and wherein the second section is substantially square in shape. The source antenna is configured to emit one or more electromagnetic signals through the FSS, wherein the FSS causes the one or more signals to form at least a first beam corresponding to the first section, and wherein the FSS causes the one or more signals to form at least a second beam corresponding to the second section.

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.