Abstract: A slotted coaxial antenna design that accomplishes simultaneous UHF and either VHF broadcast, is disclosed. This design combines a DTV channel broadcast system, where the radio frequency signals are in the UHF band (i.e. slotted coaxial UHF antenna), with an NTSC broadcast system where the radio frequency is in the low and mid VHF band (i.e. circularly polarized VHF antenna), using a common antenna aperture.

Abstract: A slotted coaxial antenna design that accomplishes simultaneous DTV and NTSC broadcast with minimal tower windloading is disclosed. In a preferred embodiment, the antenna design includes a VHF slotted coaxial antenna that acts as a framework to house multiple UHF slotted coaxial antennas, wherein the beam tilt of each UHF antenna can be independently adjusted. The one or more UHF slotted coaxial antennas, which each acts as an UHF outer conductor, and the one or more VHF couplers, which surround the VHF inner conductor, configure an arrangement such that the UHF antennas and VHF couplers share a common aperture, namely, the VHF antenna. This antenna design allows for high band VHF/UHF broadcast of DTV and NTSC signals while being easily adaptable to existing slotted coaxial antennas.

Abstract: An antenna for broadband multiplexing is disclosed. The antenna includes a first set of curved dipole members and a second set of curved dipole members arranged in a helical shape. One set of the dipole members is set with approximately 36° between each dipole member in the set. The other set of dipole members is set with approximately 27.5° between each dipole member in the set. The setting of the dipole members at the designated angles increases the bandwidth that the antenna can accommodate.

Abstract: A slotted coaxial antenna design that accomplishes simultaneous UHF and either VHF broadcast, is disclosed. This design combines a DTV channel broadcast system, where the radio frequency signals are in the UHF band (i.e. slotted coaxial UHF antenna), with an NTSC broadcast system where the radio frequency is in the low and mid VHF band (i.e. circularly polarized VHF antenna), using a common antenna aperture.

Abstract: A slotted coaxial antenna design that accomplishes simultaneous DTV and NTSC broadcast with minimal tower wind loading, is disclosed. In a preferred embodiment, the antenna design comprises a VHF slotted coaxial antenna that acts as a framework to house multiple UHF slotted coaxial antennas. The one or more UHF slotted coaxial antennas, which each acts as an UHF outer conductor, and one or more VHF couplers, that surrounds the VHF inner conductor, configures an arrangement such that the UHF antennas and VHF couplers share a common aperture; namely, the VHF antenna. This antenna design allows for high band VHF/UHF broadcast of DTV and NTSC signals while being easily adaptable to existing slotted coaxial antennas.

Abstract: A slotted coaxial antenna design that accomplishes four-way branch feeding without the use of feedlines, is disclosed. In a preferred embodiment, the antenna design is based on a number of layered coaxial feeds where each layer feeds the next outer layer. The internally branch fed slotted coaxial antenna design produces substantially no beam sway over at least four television channels, can accommodate pressurizing for increased power handling, and provides desirable antenna output response performance suitable for digital TV transmission and NTSC antenna systems.

Abstract: A digital signal, beam radiation antenna consisting of a cylindrical mast having an inner tubular conductor and an outer tubular conductor, and means for exciting said inner conductor to establish a traveling wave internal to said antenna. Moreover, there are spaced slots in said outer conductor defining an illumination aperture coupled to the inner conductor and for radiating the beam from the antenna. This establishes the illumination along the aperture so as to produce a high beam tilt of the order of 0.6-3.5 degrees from the horizontal for the beam radiation; further, for varying the phase from layer to layer, such that there are substantially no null variations in the elevation pattern of the beam.

Abstract: A technique and arrangement for lowering the mismatch normally obtained, thereby increasing the bandwidth, in a standard rectangular-to-coaxial waveguide "T" junction coupling in an antenna system, such arrangement including, in a T-junction of a coaxial transmission line to a waveguide transmission line in which measured impedance values in the range of approximate 30 MHz in the UHF band must be within a 1.1:1 circle of voltage standing wave ratio, the improvement which achieves minimal reflection over said range of frequencies, according to which a diconical slug is connected between an upper and lower portion of the coaxial transmission line and mounted for support within the structure of the waveguide transmission line, and in which said diconical slug includes back-to-back conical sections such that the large diameter rims of the sections confront each other.

Abstract: A specially designed, Z-shaped, parasitic dipole is spaced radially outwardly from the slot provided in a cylindrical antenna; a controlled amount of energy which is in a horizontally polarized direction is coupled to the Z-shaped dipole so as to radiate energy into the vertical plane, thus creating a variable circularly polarized antenna capable of adding a selectable amount of vertical component to the horizontal in quadrature; since the dipole element, which parasitically develops its polarized energy, is in the same horizontal plane as the polarized energy emanating from the slot, a good, i.e. constant, axial ratio is maintained throughout the elevation pattern.