An antenna structure according to an embodiment of the present disclosure includes an antenna unit array including a plurality of antenna units, and a parasitic element disposed to be adjacent to the antenna units and to be electrically and physically separated from the antenna units. Each of the antenna units includes a radiator, and a transmission line including a first transmission line and a second transmission line connected to the radiator in different directions. The parasitic element includes a first parasitic element disposed between the first transmission line and the second transmission line included in the same antenna unit, and a second parasitic element disposed between the first transmission line and the second transmission line included in different neighboring antenna units. The second parasitic element includes a branched portion including a first branched portion and a second branched portion bent in different directions.

Aspects described herein relate to a base station for providing air-to-ground wireless communication over various altitudes. The base station includes a first antenna array comprising one or more antennas configured to form a first cell coverage area extending substantially from a horizon up to a first elevation angle away from the first antenna array to a predetermined distance from the first antenna array. The base station further includes a second antenna array configured at an uptilt elevation angle to form a second cell coverage area extending at least from the first elevation angle to a second elevation away from the second antenna array, wherein the first cell coverage area and the second cell coverage area are concentric to define the ATG cell at least to the predetermined distance and up to a predetermined elevation.

Aspects described herein relate to a base station for providing air-to-ground wireless communication over various altitudes. The base station includes a first antenna array comprising one or more antennas configured to form a first cell coverage area extending substantially from a horizon up to a first elevation angle away from the first antenna array to a predetermined distance from the first antenna array. The base station further includes a second antenna array configured at an uptilt elevation angle to form a second cell coverage area extending at least from the first elevation angle to a second elevation away from the second antenna array, wherein the first cell coverage area and the second cell coverage area are concentric to define the ATG cell at least to the predetermined distance and up to a predetermined elevation.

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 apparatus is provided that includes a set of antenna elements and switching nodes. Each switching node has physical interconnects to a sub-set of the antenna elements for transferring communication signals and the switching nodes have physical interconnects to other switching nodes forming a network of switching nodes for transferring communication signals between switching nodes. The apparatus also includes a controller for controlling operation of switching nodes to control use of the physical interconnects between switching nodes and control creation of different patterns of antenna elements operationally interconnected via multiple operationally interconnected switching nodes.

Provided are systems and methods of using of optical delay lines in RF imagers, e.g., Ultra-wideband (UWB) imagers. In an embodiment, a modulator can be configured to convert radio-frequency signals to optical signal. First and second optical delay lines delay respective first and second optical signals converted by the modulator, and a photodetector can convert the delayed optical signals to at least one electrical signal corresponding to at least one pixel of a radio frequency image. The disclosed systems and methods can also further form a radio-frequency image based on output from the photodetector. In still further embodiments, the photodetector can receive modulated optical signals from an array of optical delays. Also provided are related methods of using the disclosed systems and devices.

Provided are systems and methods of using of optical delay lines in RF imagers, e.g., Ultra-wideband (UWB) imagers. In an embodiment, a modulator can be configured to convert radio-frequency signals to optical signal. First and second optical delay lines delay respective first and second optical signals converted by the modulator, and a photodetector can convert the delayed optical signals to at least one electrical signal corresponding to at least one pixel of a radio frequency image. The disclosed systems and methods can also further form a radio-frequency image based on output from the photodetector. In still further embodiments, the photodetector can receive modulated optical signals from an array of optical delays. Also provided are related methods of using the disclosed systems and devices.

Disclosed is a radar for a vehicle configured to detect objects around a vehicle using an antenna, and the radar includes a substrate-integrated waveguide (SIW) in which a plurality of bent slots is formed, at least one processor electrically connected to the substrate-integrated waveguide, and a differential line electrically connecting the substrate-integrated waveguide to the at least one processor.

There are provided mechanisms for beam forming using an antenna array comprising dual polarized elements. A method comprises generating one or two beam ports. The one or two beam ports are defined by combining at least two non-overlapping subarrays. Each subarray has two subarray ports. The two subarray ports have identical power patterns and mutually orthogonal polarizations. The at least two non-overlapping subarrays are combined via expansion weights. The expansion weights and map the one or two beam ports to subarray ports such that the one or two beam ports have the same power pattern as the subarrays. At least some of the expansion weights have identical non-zero magnitude and are related in phase to form a transmission lobe. The method comprises transmitting signals using said one or two beam ports.

The disclosure relates to a 5.sup.th generation (5G) or pre-5G communication system for supporting a data transmission rate higher than that of a 4.sup.th generation (4G) communication system such as long term evolution (LTE). An electronic device including an antenna in a wireless communication system is provided. The electronic device includes a radiator, a body, and a feeding circuit for transmitting a signal, wherein the radiator is coupled to at least a part of the body, the feeding circuit is coupled to the body to support the body, and the radiator is disposed to be spaced apart from the feeding circuit to form an air gap.