A monopole antenna assembly includes a cable having a cable inner conductor and a cable outer conductor. The monopole antenna assembly includes an antenna base including a ground plane. The ground plane is electrically connected to the cable outer conductor using a compression connection. The monopole antenna assembly includes a monopole radiator having a radiating element and a cable connection element extending from the radiating element. The crimp element is coupled to the cable inner conductor at a compression connection.

In various implementations, designs of relatively simple ultra-wideband STAR front-end systems are provided. For example, such systems may include implementations utilizing a plurality of antenna arms in which a first portion of the arms is configured to transmit and a second portion of the arms is configured to receive. In one implementation, for example, a co-channel simultaneous transmit and receive (STAR) monostatic aperture configuration includes a single-polarized multi-port monostatic co-channel simultaneous transmit and receive (c-STAR) spiral antenna aperture. Other examples are also provided.

In various implementations, designs of relatively simple ultra-wideband STAR front-end systems are provided. For example, such systems may include implementations utilizing a plurality of antenna arms in which a first portion of the arms is configured to transmit and a second portion of the arms is configured to receive. In one implementation, for example, a co-channel simultaneous transmit and receive (STAR) monostatic aperture configuration includes a single-polarized multi-port monostatic co-channel simultaneous transmit and receive (c-STAR) spiral antenna aperture. Other examples are also provided.

A modular monopole for wireless communications includes: an antenna module having a floor, a ceiling and a side wall that form an antenna compartment, wherein at least one antenna resides within the antenna compartment; a radio module having a floor, a ceiling and a side wall that form a radio compartment, wherein at least one remote radio unit (RRU) resides within the radio compartment; and a base. The base, the radio module, and the antenna module are arranged in vertically stacked relationship, with the base below the radio module and the antenna module above the radio module.

Systems and devices relating to antennas and antenna systems. A horizontal omnidirectional antenna has two dipoles with each dipole being in a V-configuration such that the arms of the dipole define an angle. The two dipoles are arranged so that the angles defined by each of the dipoles face and open toward each other. The horizontal omnidirectional antenna can be configured to operate with specific frequency bands. By nesting two instances of this antenna, with one configured for high band frequencies and one configured for low band frequencies, a dualband omnidirectional antenna can be obtained. The resulting antenna is physically compact and can be used in small MIMO systems along with vertical omnidirectional antennas.

An antenna system is provided that includes an antenna having an elongated conducting segment, such as a metal rod. An anisotropic metamaterial surrounds the elongated conducting segment of the antenna. The presence of the metamaterial remarkably expands the VSWR <2. An example antenna is a monopole antenna, such as a quarter-wavelength monopole antenna, surrounded by the metamaterial.

An antenna system is provided that includes an antenna having an elongated conducting segment, such as a metal rod. An anisotropic metamaterial surrounds the elongated conducting segment of the antenna. The presence of the metamaterial remarkably expands the VSWR <2. An example antenna is a monopole antenna, such as a quarter-wavelength monopole antenna, surrounded by the metamaterial.

An antenna device mounted on a roof surface of a vehicle roof includes a ground plate disposed on the roof surface, an antenna ground, a first antenna element, and a second antenna element. The antenna ground is disposed on a plane perpendicular to the ground plate apart from a ground plate surface by a predetermined distance in a direction perpendicular to the ground plate surface. The first antenna element, whose first base end portion is connected to a first predetermined position of the antenna ground, extends from the first base end portion to a first front end portion in a direction moving away from the antenna ground. The second antenna element, whose second base end portion is connected to a second predetermined position of the antenna ground, extends from the second base end portion to a second front end portion in a direction moving away from the antenna ground.

An antenna device mounted on a roof surface of a vehicle roof includes a ground plate disposed on the roof surface, an antenna ground, a first antenna element, and a second antenna element. The antenna ground is disposed on a plane perpendicular to the ground plate apart from a ground plate surface by a predetermined distance in a direction perpendicular to the ground plate surface. The first antenna element, whose first base end portion is connected to a first predetermined position of the antenna ground, extends from the first base end portion to a first front end portion in a direction moving away from the antenna ground. The second antenna element, whose second base end portion is connected to a second predetermined position of the antenna ground, extends from the second base end portion to a second front end portion in a direction moving away from the antenna ground.

Surface elements, such as protrusions, are provided for use on the surface of flow-following apparatuses, such as surface drifters or subsurface drogues, to enhance the hydrodynamic properties of the apparatus and enhance their capabilities to follow fluid motion. The protrusions may comprise helical strakes or splitter plates for optimizing the drag-to-inertia ratio of the flow-following apparatus, with the goal to enhance their flow-following capabilities. In some embodiments, the flow-following apparatus has a generally axisymmetric body shape, such as having a cylindrical, spherical or oblong shape. The flow-following apparatus may further comprise a position tracking device to track flow motion such as ocean currents.