A dual-polarized duplex antenna includes a top-layer dielectric substrate; a metal reflective ground plate below the top-layer dielectric substrate; vertically-placed duplex baluns for duplexing operation between the top-layer dielectric substrate and the metal reflective ground plate; and four dipole arms horizontally printed on an upper surface of the top-layer dielectric substrate. Each of the duplex balun includes a vertical dielectric substrate, a balun feedline printed on a front side of the vertical dielectric substrate, and a ground plane with a printed slot line printed on a reverse side of the vertical dielectric substrate. The balun feedline includes a low-pass filter, a high-pass filter and a microstrip feeding structure serving as a connection. The low-pass filter and the high-pass filter are located on two sides of the slot line, and are connected together by the microstrip feeding structure.

Provided is an antenna element resistant to loss of electrical performance even when water droplets become attached thereto. The antenna element of the present invention is provided with a conductor portion and is characterized in that, at a location on a surface of the conductor portion in which the field intensity during operation is stronger than in other locations, a first dielectric having a thickness of not less than 0.005λ is formed, wherein λ is the vacuum wavelength of the electromagnetic waves of an antenna operation frequency.

Embodiments of the present disclosure provide methods, apparatuses, devices and systems related to the implementation of a multi-layer printed circuit board (PCB) radio-frequency antenna featuring, a printed radiating element coupled to an absorbing element embedded in the PCB. The embedded element is configured within the PCB layers to prevent out-of-phase reflections to the bore-sight direction.

An antenna includes a dielectric substrate, an antenna element formed on a first surface of the dielectric substrate, a ground element formed on a second surface of the dielectric substrate, and a metal conductor plate disposed over, and at a spaced distance from, the first surface of the dielectric substrate, the metal conductor plate being larger than the ground element.

A transmission line having, for example, a first frequency-selecting surface.

Provided is an LC resonant antenna including: an inductor layer provided with a coil-shaped inductor; and a capacitor layer laminated on the inductor layer in a direction of an axis along a coil center of the inductor. The capacitor layer includes a capacitor connected to the inductor. The capacitor includes a pair of electrode plates arranged in parallel at a distance from each other in a laminating direction.

An antenna apparatus includes: a feed line; a first ground layer including surface disposed above or below the feed line and spaced apart from the feed line; and an antenna pattern electrically connected to an end of the feed line and configured to transmit and/or receive a radio frequency (RF) signal, wherein the first ground layer includes a first protruding region protruding in a first longitudinal direction of the surface toward the antenna pattern and at least partially overlapping the feed line above or below the feed line, and second and third protruding regions protruding in the first longitudinal direction from positions spaced apart from the first protruding region in opposite lateral directions of the surface.

Provided is an antenna device which includes: an antenna element (31) that transmits or receives a radio wave; a radome (20) that covers the antenna element (31); and one first wave director (21) or a plurality of first wave directors (21) that is provided on at least any one of an external surface or an internal surface of the radome (20).

An antenna module includes an antenna and a periodic structure. The periodic structure is disposed on one side of the antenna, and includes a plural first pillars, a plural first bridge members, and a plural second pillars. The plural first pillars are arranged at intervals along a one-dimensional array. The plural first bridge members are arranged at intervals along the one-dimensional array, and are connected to a side of the plural first pillars away from the antenna, wherein the plural first bridge members define a second virtual layer. The plural of second pillars are arranged at intervals in parallel with the first pillars and are connected to a side of the plural first bridge members away from the antenna. Each of the second pillars each of and the first pillars adjacent thereto have an offset from each other in the direction perpendicular to the second virtual layer.

An antenna apparatus includes: a feed line; a first ground layer including surface disposed above or below the feed line and spaced apart from the feed line; and an antenna pattern electrically connected to an end of the feed line and configured to transmit and/or receive a radio frequency (RF) signal, wherein the first ground layer includes a first protruding region protruding in a first longitudinal direction of the surface toward the antenna pattern and at least partially overlapping the feed line above or below the feed line, and second and third protruding regions protruding in the first longitudinal direction from positions spaced apart from the first protruding region in opposite lateral directions of the surface.