A dipole arm assembly for a low frequency band radiator of a cellular base station antenna comprising: a central shaft; and at least one barrel having a first end, a second end, and a peripheral wall located between the first end and the second end, where the first end includes an end wall provided with an engagement portion, and the barrel is engaged with the central shaft through the engagement portion and disposed about the central shaft.

A dipole arm assembly for a low frequency band radiator of a cellular base station antenna comprising: a central shaft; and at least one barrel having a first end, a second end, and a peripheral wall located between the first end and the second end, where the first end includes an end wall provided with an engagement portion, and the barrel is engaged with the central shaft through the engagement portion and disposed about the central shaft.

Exemplary embodiments are disclosed of antenna assemblies configured for reception of television signals, such as high definition television (HDTV) signals. In an exemplary embodiment, an antenna assembly generally includes a VHF antenna element and a UHF antenna element. The VHF antenna element and the UHF antenna element may be parasitically coupled without a direct ohmic connection between the VHF antenna element and the UHF antenna element. The antenna assembly may be configured to be operable for receiving VHF and UHF high definition television signals without using a diplexer and a VHF balun.

A space deployable antenna apparatus includes an inflatable antenna configurable between a deflated storage position and an inflated deployed position. The inflatable antenna includes collapsible tubular elements coupled together in fluid communication. The collapsible tubular elements in the deployed position include a longitudinally extending boom tubular element, at least one driven tubular conductive element transverse to the boom tubular element, at least one reflector tubular conductive element transverse to the boom tubular element, and at least one director tubular conductive element transverse to the boom tubular element. A foam dispenser is configured to inject a solidifiable foam into the inflatable antenna to configure to the inflated deployed position.

A space deployable antenna apparatus includes an inflatable antenna configurable between a deflated storage position and an inflated deployed position. The inflatable antenna includes collapsible tubular elements coupled together in fluid communication. The collapsible tubular elements in the deployed position include a longitudinally extending boom tubular element, at least one driven tubular conductive element transverse to the boom tubular element, at least one reflector tubular conductive element transverse to the boom tubular element, and at least one director tubular conductive element transverse to the boom tubular element. A foam dispenser is configured to inject a solidifiable foam into the inflatable antenna to configure to the inflated deployed position.

Short, dual-driven groundless antennas are provided. One of the antennas includes a tubular outer conductor, a tubular inner conductor, and an electrical connector that electrically connects an opposite end of the outer conductor to the exterior of the inner conductor. The inner conductor is longitudinally disposed within the hollow axial interior of the outer conductor such that an axial gap exists between the radially inner surface of the outer conductor and the radially outer surface of the inner conductor, and the inner conductor runs at least to the opposite end of the outer conductor. Electrical signals are connected to a driven end of both the outer and inner conductors, where these signals supply power to/from the antenna whenever it is used as a transmitter/receiver, and neither of these signals needs to be connected to an electrical ground.

Short, dual-driven groundless antennas are provided. One of the antennas includes a tubular outer conductor, a tubular inner conductor, and an electrical connector that electrically connects an opposite end of the outer conductor to the exterior of the inner conductor. The inner conductor is longitudinally disposed within the hollow axial interior of the outer conductor such that an axial gap exists between the radially inner surface of the outer conductor and the radially outer surface of the inner conductor, and the inner conductor runs at least to the opposite end of the outer conductor. Electrical signals are connected to a driven end of both the outer and inner conductors, where these signals supply power to/from the antenna whenever it is used as a transmitter/receiver, and neither of these signals needs to be connected to an electrical ground.

Exemplary embodiments are disclosed of antenna assemblies configured for reception of television signals, such as high definition television (HDTV) signals. In an exemplary embodiment, an antenna assembly generally includes a VHF antenna element and a UHF antenna element. The VHF antenna element and the UHF antenna element may be parasitically coupled without a direct ohmic connection between the VHF antenna element and the UHF antenna element. The antenna assembly may be configured to be operable for receiving VHF and UHF high definition television signals without using a diplexer and a VHF balun.

An electromagnetic vector sensor (EMVS) system, having a plurality of EMVS devices consisting of a plurality of loop antenna elements spatially orthogonally integrated with and electrically isolated from a plurality of dipole antenna elements, mounted on a rotatably adjustable platform having a true north orientation, including active circuitry residing in antenna housings, and external executing software programs causing the active circuitry in cooperation with the EMVS device and receivers to determine angle of arrival and resolution of incoming wave vectors and polarization of incoming signals and to perform accurate high frequency geolocation signal processing; the programs which perform calibration and antenna element placement determination operations, also cause the system to collect data of known transmitted high frequency skywave signals, and estimate direction of arrival of unknown signals by detecting, resolving and measuring components of an electric field and a magnetic field at a single point.

An electromagnetic vector sensor (EMVS) system, having a plurality of EMVS devices consisting of a plurality of loop antenna elements spatially orthogonally integrated with and electrically isolated from a plurality of dipole antenna elements, mounted on a rotatably adjustable platform having a true north orientation, including active circuitry residing in antenna housings, and external executing software programs causing the active circuitry in cooperation with the EMVS device and receivers to determine angle of arrival and resolution of incoming wave vectors and polarization of incoming signals and to perform accurate high frequency geolocation signal processing; the programs which perform calibration and antenna element placement determination operations, also cause the system to collect data of known transmitted high frequency skywave signals, and estimate direction of arrival of unknown signals by detecting, resolving and measuring components of an electric field and a magnetic field at a single point.