A reflectarray antenna system includes an antenna feed configured to at least one of transmit and receive a wireless signal occupying a frequency band. The system also includes a reflector having a reflectarray. The reflectarray includes a plurality of reflectarray elements, where each of the reflectarray elements includes a dipole element. The dipole element of at least a portion of the plurality of reflectarray elements comprises a crossed-dipole portion and a looped-dipole portion. The plurality of reflectarray elements can be configured to selectively phase-delay the wireless signal to provide the wireless signal as a coherent beam.

The disclosure relates to suppressing surface waves in a communication device for a wireless communication system. The communication device includes a dielectric layer extending along a plane between a chassis and a glass layer, an antenna element configured to emit a radio wave, and a retroreflective structure extending inside the dielectric layer and being located adjacent to the antenna element, and where the retroreflective structure is configured to reflect the radio wave in an angle non-parallel to the plane. The retroreflective structure hence prevents parasitic channeling of the antenna energy into surface waves in and behind the glass layer and directs the radiation into the desired direction.

Base station antennas include a main module that has a first backplane that includes a first reflector. A vertically-extending array of first radiating elements is mounted to extend forwardly from the first reflector, and at least one first RF port is coupled to the vertically-extending array of first radiating elements. These antennas further include a sub-module that is attached to the first backplane. The sub-module includes a second backplane that has a second reflector that is separate from the first reflector. A vertically-extending array of second radiating elements is mounted to extend forwardly from the second reflector and is transversely spaced-apart from the vertically-extending array of first radiating elements. A plurality of second RF ports are coupled to the vertically-extending array of second radiating elements. The vertically-extending array of first radiating elements and the vertically-extending array of second radiating elements are configured to serve a common sector of a base station.

A planar antenna formed on a front surface of a substrate whose back surface serves as a ground surface, the planar antenna includes: a radiating element; a feeding line connected with the radiating element; a first ground element and a second ground element which are respectively electrically connected to the ground surface and are arranged to be opposed to each other across the feeding line; a first parasitic element extending from the first ground element to surround at least a part of the radiating element; and a second parasitic element extending from the second ground element to surround at least a part of the radiating element from an opposite direction from the first parasitic element, wherein the first ground element and the second ground element serve as impedance matching devices for the feeding line.

A planar antenna formed on a front surface of a substrate whose back surface serves as a ground surface, the planar antenna includes: a radiating element; a feeding line connected with the radiating element; a first ground element and a second ground element which are respectively electrically connected to the ground surface and are arranged to be opposed to each other across the feeding line; a first parasitic element extending from the first ground element to surround at least a part of the radiating element; and a second parasitic element extending from the second ground element to surround at least a part of the radiating element from an opposite direction from the first parasitic element, wherein the first ground element and the second ground element serve as impedance matching devices for the feeding line.

A reflection apparatus includes a base plate, where one side is used to dispose a radiation unit, and the other side is used to dispose a feeding network; a first side plate and a second side plate that are separately connected to the base plate and that are disposed opposite to each other, where the first side plate and the second side plate each extend relative to the base plate and toward the side used to dispose the feeding network; a first return plate connected to the first side plate, where the first return plate extends relative to the first side plate and toward a direction of the feeding network; and a second return plate connected to the second side plate, where the second return plate extends relative to the second side plate and toward the direction of the feeding network.

A reflection apparatus includes a base plate, where one side is used to dispose a radiation unit, and the other side is used to dispose a feeding network; a first side plate and a second side plate that are separately connected to the base plate and that are disposed opposite to each other, where the first side plate and the second side plate each extend relative to the base plate and toward the side used to dispose the feeding network; a first return plate connected to the first side plate, where the first return plate extends relative to the first side plate and toward a direction of the feeding network; and a second return plate connected to the second side plate, where the second return plate extends relative to the second side plate and toward the direction of the feeding network.

A multi-band antenna includes a reflector, and a plurality of first radiating elements on the reflector. The plurality of first radiating elements are configured to radiate a first antenna beam(s) in a first frequency band responsive to at least one feed signal. A passive radiation-filtering element is provided, which extends proximate the first antenna beam(s). The passive radiation-filtering element includes at least one of a low-pass LC circuit, a band-pass LC circuit, and a high-pass LC circuit therein, which is configured to provide a lower frequency-dependent impedance to radiation within the first frequency band relative to radiation at frequencies outside the first frequency band. The passive radiation-filtering element may be configured as a multi-segment fence having capacitive and inductive elements therein, which are electrically coupled in series.

A multi-band antenna includes a reflector, and a plurality of first radiating elements on the reflector. The plurality of first radiating elements are configured to radiate a first antenna beam(s) in a first frequency band responsive to at least one feed signal. A passive radiation-filtering element is provided, which extends proximate the first antenna beam(s). The passive radiation-filtering element includes at least one of a low-pass LC circuit, a band-pass LC circuit, and a high-pass LC circuit therein, which is configured to provide a lower frequency-dependent impedance to radiation within the first frequency band relative to radiation at frequencies outside the first frequency band. The passive radiation-filtering element may be configured as a multi-segment fence having capacitive and inductive elements therein, which are electrically coupled in series.

When three directions perpendicular to each other are defined as x-direction, y-direction and z-direction, the electromagnetic wave reception device is provided with the two or more antenna electrodes extending in the x-direction, the two or more antenna electrodes are arranged parallel to each other and arranged in the z-direction, and the two or more antenna electrodes are connected by the common lead wire, and the antenna electrodes are connected between the two or more antenna electrodes that are adjacent to each other by repeatedly applying a voltage having opposite characteristics to each other, an electromagnetic wave having a resonance frequency determined by the electromagnetic wave velocity and a distance between the antenna electrodes that are adjacent to each other is induced, and the electromagnetic wave is transmitted to a space in the z-direction.