An antenna module includes a first antenna element disposed at a first dielectric substrate, a second antenna element disposed at a second dielectric substrate, a joint connecting the first dielectric substrate and the second dielectric substrate, and a power supply line. The second dielectric substrate is different from the first dielectric substrate with respect to the normal direction. The power supply line extends from the first dielectric substrate via the joint to the second antenna element and is configured to communicate a radio-frequency signal to the second antenna element. At least a part of the power supply line at the joint is formed in a direction crossing the polarization plane of radio waves radiated by the first antenna element and the second antenna element.

A lensed multi-beam base station antenna may include a plurality of linear arrays of radiating elements, a plurality of reflectors, a sidelobe suppressor, and a lens. Each array may include a plurality of radiating elements (e.g., two or more radiating elements) that extends forwardly from a planar section of a respective reflector. The sidelobe suppressor may comprise radiofrequency (RF) absorber material that absorbs energy that is emitted by a first of the arrays and that is directed toward a reflector underneath a second of the arrays. The sidelobe suppressor may comprise a RF choke that reduces the RF energy emitted by a first of the arrays that is directed toward a reflector underneath a second of the arrays.

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.

A hybrid antenna structure includes a first metal element, a second metal element, a third metal element, a cable, and a proximity sensor. The first metal element has a feeding point. The second metal element is adjacent to and separate from the first metal element. A coupling gap is formed between the second metal element and the first metal element. The third metal element is coupled to a connection point on the second metal element. The proximity sensor is coupled through the cable to the third metal element. The second metal element and the third metal element are used as both a sensing pad and a radiation element.

Technologies directed to overlaid shared aperture array with improved total efficiency are described. One RF structure includes a first antenna with a first set of antenna elements disposed on a first plane of a support structure and a second antenna with a second set of antenna elements disposed on a second plane of the support structure. A set of parasitic antenna elements are disposed on the first plane. Two adjacent antenna elements, including one from the first plurality of antenna elements and another one from the plurality of parasitic antenna elements, are separated by the second distance.

An RF device includes a first antenna set made up of a first antenna and a second antenna, the first and second antennas being planar in shape and both lying in a common first plane, the first antenna being arranged to operate in a first frequency band and the second antenna being arranged to operate in a second frequency band; and a first isolator, the first isolator being planar in shape and lying in the first plane between the first and second antennas, the first isolator having at least one branch that is electrically conductive, the first isolator being electrically floating, the first isolator being arranged to reduce first coupling by electromagnetic radiation between the first and second antennas in the first frequency band and/or in the second frequency band.

According to an aspect, there is provided a passive antenna module for an active-passive antenna system. The passive antenna module includes a chassis for detachably mounting onto an active antenna module. The chassis includes an opening or a cavity for extending at least partially over the active antenna module when the chassis is mounted onto the active antenna module. The passive antenna module includes a ground plane layer arranged within or over said opening or cavity and fixed to the chassis. The ground plane layer includes a metallic or metallized grid. The passive antenna module includes a first antenna array including one or more first antenna elements arranged, in part, over said chassis and adjacent to said opening or cavity and, in part, over said opening or cavity. The chassis and the ground plane layer are adapted to act as ground planes for the first antenna array.

Example embodiments relate to antenna apparatus comprising a feed reflector. According to various, but not necessarily all, embodiments of the invention there is provided an apparatus, comprising: an antenna feed array; a main antenna reflector or lens; and a feed reflector; wherein the feed reflector comprises a concave reflective surface configured to reflect radio-frequency radiation from the antenna feed array towards the main antenna reflector or lens and dimensioned to adjust radio-frequency radiation transmittable from the antenna feed array to the main reflector or lens via the feed reflector by narrowing the spread of the radio-frequency radiation reflected by the feed reflector towards the main antenna reflector or lens. Example embodiments recognise that it is possible to improve gain achieved by antenna apparatus if a properly configured secondary reflector is provided close to a feed or feed array, to modify a radiation pattern which is fed to the main reflector.

An array antenna (A) in a medium (M) comprises a plurality of radiating elements (ER.sub.T) ensuring the transition between the antenna and the medium, the reflectivity of each element depending on a parameter, the reflectivity of a first element being close to that of the medium, the reflectivity of a last element being close to that of the antenna, the reflectivity parameter of the elements varying from one element to the next. A method comprises calculation of a path equal to the sum of the variations of the reflectivity from one element to the next element, optimization of the variation of the reflectivity parameter so that equivalent radar cross-section of the antenna is the lowest possible or the antenna best observes the radiation objectives, determination of the different elements as a function of said parameter, and simulation of the overall reflectivity and/or of the radiation of the antenna.

A radio frequency antenna array uses lenses and RF elements, to provide ground-based coverage for cellular communication. The antenna array can include two spherical lenses, where each spherical lens has at least two associated RF elements. Each of the RF elements associated with a given lens produces an output beam with an output area. Each lens is positioned with the other lenses in a staggered arrangement. The antenna includes a control mechanism configured to enable a user to move the RF elements along their respective tracks, and automatically phase compensate the output beams produced by the RF elements based on the relative distance between the RF elements.