An antenna array assembly comprises a ground plate, an array of radiator elements disposed in a spaced relationship with a first face of the ground plate between first and second substantially parallel conductive walls projecting from the first face of the ground plate, and a first and second conductive plate. Each of the first and second conductive plates is electrically isolated from the ground plate, and each is disposed in an upstanding relationship to the first face of the ground plate in a substantially parallel relationship with the first and second conductive walls. This provides reduced radiation in at least one direction in the hemisphere on the opposite side of the ground plate to the first face.

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.

A transmission line network is provided that includes a slow-wave transmission line to couple a first terminal to a first antenna. The transmission line network also includes a conventional transmission line to couple a second terminal to a second antenna.

An antenna module is provided to reduce the radio waves radiated toward a back lobe of the antenna module, and includes a printed circuit board (PCB) including at least one insulating layer, at least one antenna array disposed on an upper surface of the PCB, and at least one metal structure disposed on the upper surface of the PCB configured to shift a phase of radio waves radiated by the at least one antenna array and flowing along the upper surface of the PCB. The radio wave whose phase is shifted by passing through the metal structure is in a destructive interference relationship with a radio wave which is not affected by the metal structure thereby reducing the radio waves radiated toward a back lobe of the antenna module.

The disclosed embodiments include a monitoring system. The monitoring system includes a wireless device and a holding structure. The wireless device includes communications circuitry that enables wireless communications of data obtained locally by the wireless device, and an antenna coupled to the communications circuitry and configured to radiate signals including information indicative of the obtained data. The holding structure includes an engagement member configured to detachably engage the wireless device, an attachment member configured to detachably attach the engaged wireless device to a surface of an object monitored by the wireless device, and an antenna enhancing structure disposed inside the holding structure and configured to mitigate interference by the surface of the object on the signals radiated by the antenna.

The invention relates to a device (7) for measuring the surface velocity of a fluid (10) flowing in a confined space such as through a pipe or a channel (12), said device (7) comprising a patch antenna (1) with a transmitting area (1a) generating a microwave signal and a receiving area (1b) receiving the microwave signal reflected on the surface of the fluid (10), the device (7) being wherein it comprises an electrically conductive tube (8), called reflector tube, with at least the transmitting area (1a) of the patch antenna (1) mounted at one end (8a) of the reflector tube (8) to reduce the side lobes of the generated microwave signal. The invention also relates to the non-invasive method for measuring the surface velocity of the fluid using said device (7).

A vehicle includes: a roof panel; an antenna disposed on an edge portion of one side the roof panel; and a vector transformer extending from the edge portion of one side of the roof panel to an outside of the roof panel. A surface area of the vector transformer may be smaller than that of the roof panel.

Radar standing wave dampening systems and components are described. In particular, systems and components including an absorber composite including at least one of ceramic filler, magnetic filler, or conductive filler materials are described. Such components can reduce the intensity of standing waves and may also be combined in systems with one or more gradient permittivity tapes or films.

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.

An antenna apparatus includes a ground plate, a radiator, and a signal source. The radiator is disposed on the ground plate. The signal source is configured to feed an electromagnetic wave signal of a first frequency band into the radiator. A first slot and a second slot are disposed on the ground plate. Both slots are closed slots and surround the radiator, and are used to restrain current distribution on the ground plate.