Antennas such as flat panel, leaky wave antennas with directional coupler feeds and waveguides are disclosed. In one example, an antenna includes a surface having antenna elements, a guided wave transmission line, and a coupling surface. The guided wave transmission line provides a guided feed wave. The coupling surface is between and separates the guided wave transmission line and the surface having antenna elements. The coupling surface controls coupling of the guided feed wave to the antenna elements. The coupling surface can also spatially filter the guided feed wave to provide a more uniform power density for the antenna elements. The guided feed wave can be a high power density electromagnetic wave or a density radially decaying electromagnetic wave.

An adaptive detection and nulling system includes an antenna or radio frequency aperture, an electronically tunable radome placed over the antenna or radio frequency aperture, the radome including a plurality of scatterers on a substrate, and one or more tunable reactance elements connecting at least two of the scatterers, a microcontroller coupled to the tunable reactive elements and configured to control the reactance values of the one or more tunable reactance elements, and a sensing circuit coupled to the microcontroller, wherein inputs from the sensing circuit are used by the microcontroller to adaptively determine bias voltages to the one or more tunable reactance elements using characterization data of the radome to control the tunable reactance elements to form one or more nulls in a receive radiation pattern of the antenna.

A metasurface includes a dielectric material, a ground plane on a back side of the dielectric material; and at least one conductive element on a top surface of the dielectric material, wherein the at least one conductive element includes at least one of a ground-backed dipole or a slot array.

Methods, systems, and apparatuses, for a millimeter wave filter array are discussed. The filter array includes an array of unit cells formed using a dielectric layer of a dielectric material, the dielectric layer having a first surface and an opposing second surface. Each unit cell includes conductive sidewall layers extending at least partially between the first surface and the second surface of the dielectric layer and defining a resonant space within the dielectric layer. Each unit cell also includes a metallized layer formed on the first surface, covering at least a portion of the resonant space of the dielectric layer and electrically connected to the conductive sidewall layers. Each unit cell includes a radio-frequency input-output (RF I/O) contact formed on the first surface of the dielectric layer.

Methods, systems, and apparatuses, for a millimeter wave filter array are discussed. The filter array includes an array of unit cells formed using a dielectric layer of a dielectric material, the dielectric layer having a first surface and an opposing second surface. Each unit cell includes conductive sidewall layers extending at least partially between the first surface and the second surface of the dielectric layer and defining a resonant space within the dielectric layer. Each unit cell also includes a metallized layer formed on the first surface, covering at least a portion of the resonant space of the dielectric layer and electrically connected to the conductive sidewall layers. Each unit cell includes a radio-frequency input-output (RF I/O) contact formed on the first surface of the dielectric layer.

An electromagnetic shield is disposed in front of a radar. The radar has different angles of view in different directions. The radar has a first angle of view in a first direction and a second angle of view in a second direction. The second angle of view is smaller than the first angle of view. The second direction is orthogonal to the first direction. The electromagnetic shield has a pair of first sides and a pair of second sides. The pair of first sides face each other in the first direction. The pair of second sides face each other in the second direction. The electromagnetic shield includes a dielectric. At least one of the pair of first sides includes a structure having at least one selected from the group consisting of a projecting portion and a recessed portion.

A system for providing information to a magnetic card reader. The system comprises an antenna (in one embodiment comprising a multi-purpose antenna or an antenna module) and a microprocessor for applying a differential signal to the antenna. The differential signal represents data stored in a memory segment of the microprocessor or in a memory connected to the microprocessor. The antenna transmits an alternating magnetic field representing the information the alternating magnetic field is responsive to the differential signal and received by the magnetic card reader.

One example discloses an antenna combination device, comprising: a modulation unit; wherein the modulation unit is configured to be coupled to: a first antenna, having a first set of electromagnetic field lobes and configured to pass a first signal; a second antenna, having a second set of electromagnetic field lobes and configured to pass a second signal; wherein the modulation unit is configured to vary the first signal and the second signal, resulting in a third set of electromagnetic field lobes from a combination of the first and second sets of electromagnetic field lobes; wherein the first, second and third electromagnetic field lobes are in a same plane; and wherein a number of the third set of lobes is less than or equal to either a number of the first set of lobes or a number of the second set of lobes.

Spatial power-combining devices, and in particular, antenna structures for spatial power-combining devices are disclosed. A spatial power-combining device includes a plurality of amplifier assemblies, and each amplifier assembly includes an input antenna structure, an amplifier, and an output antenna structure. At least one of the input antenna structure and the output antenna structure may have a profile that includes tuning features, such as steps or other shapes, configured to tune or match with a desired operating frequency range. The tuning features may be configured with one or both of a signal conductor and a ground conductor of at least one of the input and output antenna structures. The tuning features may be non-symmetric across a particular signal conductor or a ground conductor, and the tuning features of a signal conductor may be non-symmetric with the tuning features of a ground conductor.

A frequency selective surface unit includes dielectric substrate(s), first resonant pattern(s) and second resonant pattern(s). A first resonant pattern is disposed on a dielectric substrate. Each of the first resonant pattern(s) includes a plurality of protruding portions. A second resonant pattern is disposed on the dielectric substrate; and the second resonant pattern and the first resonant pattern have a distance therebetween in a direction parallel to a plane where the dielectric substrate is located and/or a direction perpendicular to the dielectric substrate.