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 antenna device comprises a substrate with an installation surface, with said substrate configured to electrically connect to a ground point; a main antenna connected to the installation surface, wherein the main antenna extends away from the installation surface, has a feeding end for receiving a signal, and is configured to form a resonance current path with the substrate to generate an original radiation field; and a reflector with a shorting end and a free end, wherein the shorting end connects to the installation surface and the reflector extends away from the installation surface; and a switch with a first end, a second end, and a control end, wherein the first end electrically connects to the free end of the reflector, the second end electrically connects to the substrate, and the control end is configured to selectively control the first end and the second end in a conductive connection.

In a meta-structure having multifunctional properties according to an exemplary embodiment of the present invention, a plurality of unit blocks controlling a property of a wave is combined on a plane or in a space in a predetermined pattern to form one structure, at least one of the plurality of unit blocks is formed to have a different size, and a frequency range of a wave controlled is changed according to the size of the unit block.

Resonant frequency stability of passbands or stopbands is provided over varying incidence angles and polarizations in a dual band frequency selective surface (FSS) device. The FSS device comprises an array of fractal unit cells. The fractal elements may comprise single fractal, or double fractal, or convoluted, or split ring resonator slot elements printed on a thin dielectric substrate. Each cell includes a first fractal pattern and a second fractal pattern which interact to provide the improved performance. In one form, a two-screen fractal FSS is etched on both sides of a thin dielectric substrate. The top FSS screen's unit cell has one fractal loop patch element, while the bottom FSS screen's unit cell has a higher order iteration of the same fractal. In another form, two fractal screens are incorporated in one dielectric layer positioned between two substrate layers. In yet another form, two fractal loop slot element FSSs are provided.

An occupancy detection system for at least one vehicle seat includes: an antenna arrangement having an antenna; a control device that applies a radio-frequency transmission signal to, and receives a response signal from, the antenna arrangement; and a transmit array having a plurality of structured metallic layers disposed above each other and extending laterally, each two neighbouring metallic layers isolated from each other by an intermediate dielectric layer. The antenna arrangement transmits a radio-frequency transmission field through the transmit array onto the vehicle seat in response to the transmission signal and receives a radio-frequency response field through the transmit array to generate the response signal. The transmit array is adapted to refract at least one of the transmission field and the response field. The transmit array has a receive section that focuses a response field from a position of a vehicle seat to a position of a receive antenna.

A base station antenna includes a panel that has a ground plane, first and second arrays that have respective first and second sets of linearly arranged radiating elements mounted on the panel, and a decoupling unit positioned between a first radiating element of the first array and a first radiating element of the second array. The decoupling unit includes at least a first sidewall that faces the first radiating element of the first array, a second sidewall that faces the first radiating element of the second array and an internal cavity that is defined in the region between the sidewalls. The first and second sidewalls are electrically conductive and electrically connected to the ground plane.

Integrated antenna structures described herein include, as one example, a multi-layered printed circuit board (PCB), including an artificial magnetic conductor (AMC) cell that includes a backing metal layer defining a first inner layer of the multi-layered PCB and an AMC metal layer defining a second inner layer of the multi-layered PCB. The metal layer defining the second inner layer is separated from at least one edge of the multi-layered PCB, and a planar inverted F antenna (PIFA) surrounds the AMC cell. The AMC metal layer is configured to reflect energy radiated by the PIFA. In some embodiments, the energy radiated by the PIFA includes radio frequency waves that can be used by a receiver to power or charge an electronic device.

Aspects of the present disclosure provide apparatus, methods, processing systems, and computer readable mediums for determining a beamformer to apply to groups of two or more elements of a reconfigurable intelligent surface (RIS). The beamformer is applied to the groups of elements of the RIS to facilitate communications at the operating frequency by re-radiating radio signals via the elements of the RIS. For example, by grouping RIS elements in different manners and applying a beamformer (e.g., precoding weights) to the group as if the group were a single RIS element, the RIS can be reconfigured to behave differently to suit various operating frequencies of the radio signals.

Provided are an intelligent surface and a spatial electromagnetic wave manipulation system. The intelligent surface includes M types of electromagnetic units, where M is greater than or equal to 2. The M types of electromagnetic units are distinguished by at least one of the following: the geometric shape of the electromagnetic unit, the manipulation manner of the electromagnetic unit or the type of an electromagnetic parameter manipulated by the electromagnetic unit.

A radio-frequency identification (RFID) tag with improved sensitivity includes an antenna that receives a radio-frequency (RF) signal and wireless power from an RFID reader. The RFID tag further includes a circuit that varies a reflection coefficient of the antenna to transmit a reflected signal to the reader, the reflected signal having periods of high reflectance when a relatively high amount of the RF signal is reflected, and low reflectance periods when a relatively low amount of the RF signal is reflected. The reflectance of the antenna is sufficiently low during the high reflectance periods to enable wireless power reception during the high reflectance periods.