Abstract: An antenna installation having a tower including supporting a mast supported adjacent its upper end and in turn being supported adjacent its lower end by a first hinge mechanism for pivotal movement about a first horizontally disposed hinge axis between a generally horizontally disposed lowered and vertically upstanding use positions; an antenna including a boom mounted on said mast and a plurality of antenna elements mounted on said boom to lie within plane disposed generally normal to said mast when in upstanding use position; and a hinge mechanism for supporting the antenna for pivotal movement about a second generally horizontally disposed hinge axis adopted to be disposed parallel to the first hinge axis and including gravity responsive latch means for controlling against pivotal movement of the antenna relative to the mast.

Abstract: An apparatus includes a 3D array of circuit elements and control lines for coupling a remote control device to the circuit elements in the array. Each circuit element is configured to transform from one circuit state to another circuit state in response to a change in a control signal received from one of the control lines. The 3D array includes a region that behaves as a metamaterial in a selected frequency when the circuit elements of the region are in one set of circuit states and as a normal refractive medium in the selected frequency when the circuit elements of the region are another set of circuit states.

Abstract: An aircraft radio antenna assembly including a mast; an omni-directional antenna connected to a first end of the mast; and a pivot and movable latch connection system at a second end of the mast. When the pivot and latch connection system is attached to an aircraft, the mast can be located at a stowed position or pivoted up to a deployed position and latched into the deployed position. The assembly can also include a break-away system to allow part of the antenna assembly to detach without significantly damaging the antenna assembly.

Abstract: An antenna system for an interleaved branch fed antenna is provided, wherein the interleaved branch fed antenna shares the same centerline as a series fed antenna. The antenna systems are easily fed while preserving similar coverage and maintaining similar aperture space.

Abstract: A mounting configuration for a plurality of broadcast antennas that enables location of each antenna above the top of a support structure. Antenna spacing greater than the cross section of the support structure is obtained by mounting the antennas at either end of support beams extending beyond the support structure. Controlling antenna spacing improves RF signal patterns by reducing proximity to and thereby effects of nearby antennas and or support structure. Overturning moments of the antennas are reduced by mounting the antennas to the support beams at desired positions along their length, reducing structural requirements of the antennas and the support structure. Additional support may be obtained by also securing the antennas to a lower support beam.

Abstract: A log-periodic dipole antenna (10) includes a boom (12) which through insulator blocks (15) carries a plurality of elements (13) consisting of element halves (13A, 13B) which extend in opposite directions from the boom (12). Spaced transmission wires (38A, 38B) extend along the boom (12) without crossing each other and yet communicate with alternatingly opposite element halves (13A, 13B) of adjacent elements (13) in view of their connection with brackets (30A, 30B) attached to element halves (13A, 13B). The transmission wires (38A, 38B) are spaced at the point of communication with each element (13) a distance proportional to the impedance of that particular element (13) by virtue of their being attached at different locations along the brackets (30A, 30B).

Abstract: A tower (1) for wind power installations, on which at least one rotor (2) that can be driven by wind can be rotatably supported, has an especially low mass relative to its load-bearing capacity, stability, and rigidity, if it has a tower portion (3), tapering toward the top, with a bulging outer wall (4) that is convex in longitudinal section.

Abstract: A tower for a wireless transmission device including at least one shaft extending upwardly between top and bottom portions, transverse spars extending outwardly from the shaft, at least one brace connected to at least one of the spars and extending between the top and bottom portions, wherein the transverse spars are articulated in relation to the shaft and form, in conjunction with the braces, cells conserving parallelism of the spars.

Abstract: A method of aligning an antenna within a predetermined azimuth direction, in which the antenna is hingeably connected to a support. In response to processed positioning data received by a first global positioning system receiver dish from a global positioning satellite system, the first receiver dish being connected to the antenna and locatable at predetermined first and second positions away from the antenna, the first receiver dish determines an antenna azimuth direction and is moved from the antenna azimuth direction towards the predetermined azimuth direction so as to align the antenna.

Abstract: An antenna system is presented including an electrically conductive radiating mast that extends generally vertical relative to earth ground. The mast has a lower end for receiving RF energy for radiation thereby at an operating RF frequency and an upper end. A plurality of N radial, electrically conductive, wires are provided with each having an inner end and an outer end. The inner ends of the radial wires are electrically connected together and located proximate to the vertical mast. The radial wires are elevated throughout their lengths above the level of earth ground and extend radially outward from the vertical mast. A tuning device, such as an adjustable inductor, is connected to the radial wires for adjusting the impedance thereof such that the radial wires resonate at the operating frequency.

Abstract: An antenna system is presented including an electrically conductive radiating mast that extends generally vertical relative to earth ground. The mast has a lower end for receiving RF energy for radiation thereby at an operating RF frequency and an upper end. A plurality of N radial, electrically conductive, wires are provided with each having an inner end and an outer end. The inner ends of the radial wires are electrically connected together and located proximate to the vertical mast. The radial wires are elevated throughout their lengths above the level of earth ground and extend radially outward from the vertical mast. A tuning device, such as an adjustable inductor, is connected to the radial wires for adjusting the impedance thereof such that the radial wires resonate at the operating frequency.

Abstract: Mast for a source of electromagnetic waves, comprising a number of peripheral rods (1) extending in vertical direction, the peripheral rods being mutually connected by transverse rods (2), and forming a space for accommodating the electromagnetic wave source in, or at the top of, the mast. The mast is provided with a stabilization device for reducing uncontrollable natural vibrations in the event of hypercritical wind speeds, said device being accommodated in, or on top of, the mast. The mast advantageously supports a lining of dishes (7).

Abstract: An antenna system that includes a directional antenna designed to reduce the occurrence of side lobes, thus reducing the possibility of interference with other radio frequencies is disclosed. The directional antenna includes an antenna member and a reflecting tube. The reflective tube is sleeved over the antenna member. The reflective serves to block unwanted radial side lobes. The directional antenna can also include provisions that assist in suspending the antenna member within the reflective tube.

Abstract: An antenna mast is disclosed that has N faces, N corners that are intermediate adjacent faces, and N fins that each include a plurality of bars that extend between a first side and a second side of each fin in a direction opposite to an adjacent one of the plurality of bars. The antenna mast disclosed is lightweight, easy to maneuver and utilizes minimal raw material, while maintaining its structural integrity.

Abstract: An antenna (10) includes a boom (12) which through insulator blocks (15) carries a plurality of elements (13) consisting of element halves (13A, 13B) which extend in opposite directions from the boom (12). The insulator block (15) includes compartments (18) to receive the element halves (13A, 13B) and a pedestal (38) formed below each compartment (18) provides strength to that area of the block (15). The block (15) has opposed sidewalls (22) with surfaces (24) to receive the boom (12). The bands (33) of a clamp hold the boom (12) and are received in the space between the pedestals (29) and the sidewalls (22). A cross-shaped member (27) is also located between the sidewalls (22) to strengthen the block (15) while at the same time reducing the weight thereof.

Abstract: An antenna system is disclosed that includes a mast, waveguides positioned about the mast, and a feed system positioned external to the mast and between adjacent waveguides, such the feed system can be easily serviced. The waveguides include spherical radiator elements that are easy to manufacture, and thus reduce the cost associated with wideband cavity-backed antennas.

Abstract: An antenna mast is disclosed that has N faces, N corners that are intermediate adjacent faces, and N fins that each include a plurality of bars that extend between a first side and a second side of each fin in a direction opposite to an adjacent one of the plurality of bars. The antenna mast disclosed is lightweight, easy to maneuver and utilizes minimal raw material, while maintaining its structural integrity.

Abstract: Equipment and methods for aligning the antennas of two transceivers of a point-to-point wireless millimeter wave communications link and keeping them aligned. Each of two communicating antennas is equipped with a telescopic camera connected to a processor programmed to recognize landscape images. The processors are programmed to remember the pattern of the landscape as it appears when the antennas are aligned. Each of the cameras then view the landscape periodically or continuously and if the landscape in view changes by more than a predetermined amount a signal is provided to indicate a misalignment. An operator can then take corrective action or alternatively the antenna system can be configured for remote or automatic realignment based of feedback from the camera.

Abstract: A distributed antenna array includes a plurality of antenna elements and a plurality of power amplifiers, each power amplifier being operatively coupled with one of the antenna elements and mounted closely adjacent to the associated antenna element, such that no appreciable power loss occurs between the power amplifier and the associated antenna element. Each power amplifier is a relatively low power, relatively low cost per watt linear power amplifier chip. The antenna array may be used in various installations, including cellular, PCS, MMDS, LMDS and in-building communication systems such as LANS or WLANS.

Abstract: An easily-constructed foundation for an antenna support tower is provided that requires no fabricated support surface at the installation site. The foundation is a radial array of prefabricated buildings connected near their inner corners to each other. In a first embodiment, one leg of a multi-legged tower rests on each building, the buildings transferring forces from the tower to the support surface below the buildings. In a second embodiment, a tapered monopole tower is located in the center of the array of buildings. The monopole tower may rest on a prepared surface or may be supported above the support surface. Support structures, each having a central ring and radially extending arms, are attached at the building connection points, one support structure above the other. The monopole tower is positioned within the central ring, transferring lateral loads through the ring and arms to the buildings, negating the need for a moment base.

Abstract: Mast for a source of electromagnetic waves, comprising a number of peripheral rods (1) extending in vertical direction, the peripheral rods being mutually connected by transverse rods (2), and forming a space for accommodating the electromagnetic wave source in, or at the top of, the mast. The mast is provided with a stabilisation device for reducing uncontrollable natural vibrations in the event of hypercritical wind speeds, said device being accommodated in, or on top of, the mast. The mast advantageously supports a lining of dishes (7).

Abstract: An antenna support for a power transmission tower having a vertically disposed mast extending upwardly through the tower with the antenna support being mounted on the upper end of the mast. The weight of antenna support is transferred to the legs of the tower rather than to the mast through the use of support bracing extending between the elongated pipe and the tower. An antenna platform is mounted on the upper end of the mast with the weight thereof being supported by the elongated pipe. The platform is comprised of three triangular-shaped platform sections having mounting rings at the inner ends thereof which are slipped over the upper end of the mast with the lowermost mounting ring resting upon the upper end of the elongated pipe. The antenna support may be mounted on a cellular transmitting/receiving tower or on a guy-wired mast.

Abstract: An antenna tower and support apparatus includes a foundation and a building mounted on the foundation, the building including a plurality of vertically spaced apart building sections (preferably two, three or more), a bottom and a top. A tower is supported upon the top of the building. A plurality of antenna are attached at multiple elevational positions. Each building section has a security area that is separate from the security area of the other building sections. A plurality of antenna portals are provided at least one on each building section. A plurality of antenna cables are provided, each cable extending from an antenna to a security area of a building section via an antenna portal, wherein each security area has at least one antenna cable that extends to it. Each security area has telecommunications equipment that is connected to one of the antenna cables.

Abstract: An apparatus and method for rigidly supporting an antenna mast or other object relative to a structure in a desired position. The apparatus may comprise a first bracket that is affixable to the structure and a second bracket that is slidably affixed to the first bracket and capable of being locked in a desired position relative to the first bracket. A mast-supporting or object-supporting collar or clamp may be rotatably and slidably affixed to the second bracket and is capable of being locked in a desired position relative to the second bracket.

Abstract: An compact and rugged antenna system particularly suited to direction finding includes a plurality of antenna arrays for receiving respective frequency bands and colocated on a mast with separation between antenna arrays along the mast. The mast includes a coil wound of an insulator and functioning as a loaded inductor to shift the mast resonance out of the frequency band of the antenna system. A VHF dipole array having elements shaped to reduce scattering to UHF and SHF arrays is supported on movable arms which allow retraction that reduces height and provides mechanical protection to one or more other arrays as well as damping against vibration by contacting the mast with shaped portions of the dipole elements. The bowtie elements of the UHF array are angled at a central region to optimize array diameter at low UHF frequencies. A finned RF electronics housing is preferably provided which reduces solar loading and dissipates heat from antenna electronics.

Abstract: An all-weather housing for outdoor microwave radio nodes arranged in a network, each node capable of directing or receiving a beam of microwave energy in a selected direction, the housing including a shroud enclosing a transceiver, antenna, switches, and utilities. Each shroud has a radome projecting from the shroud in line of sight relation to other radomes in the network. A microwave radio transceiver is disposed within the shroud, operating on a scheduled transmission and reception basis in accordance with a schedule provided in a control channel amidst data. A ball-shaped microwave refractive lens is located adjacent to the radome, inside of the shroud, with a curved array of feed ports and switches, with the feed ports communicating microwave energy between the transceiver and the radome through the lens in multiple selected directions.

Abstract: An existing monopole is strengthened to accommodate loading associated with additional elements included in over-the-air communications systems by fixing strengthening elements to the exterior surface of the monopole. Monopole strengthening may require base plate strengthening, adding anchor bolts and/or foundation strengthening. This permits an existing monopole to accommodate more elements than were initially envisioned when the monopole was initially erected.

Abstract: An existing monopole is strengthened to accommodate loading associated with additional elements included in over-the-air communications systems by placing expanding foam and aggregate, light weight aggregate concrete, normal weight aggregate concrete or other types of fill material into the hollow bore in the interior of the monopole. Monopole strengthening may equire base plate strengthening, adding anchor bolts and/or foundation strenghtening. This permits an existing monopole to accommodate more elements than were initially envisioned when the monopole was initially erected.

Abstract: A mobile cellular telephone tower comprises a self-propelled base and a tower connected to the base. The tower includes a base segment and at least a first extendable segment operatively connected to a second extendable segment. A winch is connected to the base, and a first cable is connected between the base segment and the first extendable segment to extend the first extendable segment. A second cable is connected between the winch and the second extendable segment to retract the second extendable segment. Cellular telephone network testing equipment mounted on the tower.

Abstract: An easily-constructed foundation for an antenna support tower is provided that requires no fabricated support surface at the installation site. The foundation is a radial array of prefabricated buildings connected near their inner corners to each other. In a first embodiment, one leg of a multi-legged tower rests on each building, the buildings transferring forces from the tower to the support surface below the buildings. In a second embodiment, a tapered monopole tower is located in the center of the array of buildings. The monopole tower may rest on a prepared surface or may be supported above the support surface. Support structures, each having a central ring and radially extending arms, are attached at the building connection points, one support structure above the other. The monopole tower is positioned within the central ring, transferring lateral loads through the ring and arms to the buildings, negating the need for a moment base.

Abstract: A service tower integrates a water tank and an antenna mast into a single structure. The integrated tower structure has a bottom tank for holding water, a top member for mounting the antenna, and a middle transitional section that connects the larger diameter tanker to the smaller mast. A cable is port formed in the bottom end of the mast to receive communications cables from the exterior sidewall of the tank and deliver them to the interior sidewall of the mast. An antenna support is fastened to the mast above the cable port. A hollow support arm is fastened to the mast about an opening forming a passageway from the interior of the mast to the interior of the support arm. Cables are routed through the passageway to the antenna from inside the mast.

Abstract: Broadcast towers used for the co-location of wireless antennas and having a plurality of antenna wires spaced from a support are modified with an insulation system including flexible, non-conductive insulation sleeves to cover the lower section of the antenna wires. These sleeves include an inner tubular member having an inner diameter greater than the outer diameter of the antenna wire and an outer tubular member having an inner diameter greater than the outer diameter of the inner tubular member. An improved cabinet for isolating cables is also described. The cabinet includes a conductive housing having a top wall, a bottom wall, and parallel first and second side walls joining said top and bottom walls, and removable front and back plates. A non-conductive cable support frame is slidable within said housing. The side walls have corresponding attachment means, whereby a side wall of one cabinet can be aligned with and attached to a side wall of another cabinet of the same construction.

Abstract: An antenna system installation comprising a tower/support structure, and an antenna structure mounted at the top of said tower/support structure, said antenna structure comprises a plurality of antenna elements, a plurality of power amplifiers, each power amplifier being operatively coupled with one of said antenna elements and mounted closely adjacent to the associated antenna element, such that no appreciable power loss occurs between the power amplifier and the associated antenna element, each said power amplifier comprising a relatively low power, relatively low cost per watt linear power amplifier chip, a first RF to fiber transceiver mounted at the top of said tower/support structure and operatively coupled with said antenna structure, and a second RF to fiber transceiver mounted adjacent a base portion of said tower/support structure and coupled with said first RF transceiver by an optical fiber cable.

Abstract: An antenna system characterized by decoupling the antenna mast for multiple bands by use of a quarter wave decoupling stub or by the use of a frequency relative trap. As a result the antenna has multiple resonances simultaneously. The foregoing also can be accomplished by selecting antenna mast lengths that are harmonically related to provide a single element with multiple resonances without external devices. A diplexer comprising the combination of high and low pass filters and a broadcast coupler can be connected to the antenna feed point with transceivers operating in the different bands being connected to the high and low pass filters. The simultaneous multiple resonances ensure a matched impedance at the antenna feed point so that when a communications device is connected by a length of coax to the antenna feed point the matched impedance will be maintained at the feed point regardless of the length of the coax.

Abstract: A direction-finding antenna constructed from polymer composite materials which are electrically conductive is shown with the polymer composite materials replacing traditional metal materials. An inherent advantage of replacing metal materials is significantly lower radar reflectivity (radar cross section) and lower weight. The reduced radar reflectivity reduces the range of detectability of the antenna by possible adversaries. Despite significantly lower radar reflectivity, the antenna assembly has direction-finding characteristics which are essentially equivalent to traditional metal antennas.

Abstract: An antenna assembly includes a straw having a substantially linear passageway and a helix base coil with an angled tapered guide, the passageway having a width wider than the widest portion of the angled tapered guide. An antenna element has a stopper portion and a straw. For a vertical retraction and a slanted extension, the antenna element is movable between a slanted position wherein the antenna element is inclined from the housing when the stopper of the antenna element is positioned inside the angled tapered guide of the base coil and a retracted position substantially within the straw inside the radio housing wherein the antenna element is retracted vertically within the straw.

Abstract: A wireless telecommunication antenna mount has a platform which carries a plurality of antennas. The platform is mounted on a pedestal in an angularly adjusted position. The pedestal is mounted on the top of an electric power transmission tower in a position above the tower.

Abstract: A personnel platform assembly and antenna support assembly for wireless communication transmitting and receiving devices such as antennas used in at least cellular telephone networks. The support assembly includes a support frame connectable upon an aerial tower which is adapted for supporting wireless communication transmitting and receiving devices thereupon. A connecting assembly is provided for fixing the support assembly at an above-ground elevation upon the aerial tower and a guide rail is suspended at a distance about the connecting assembly or central column of the tower. The guide rail is adapted for accepting a coupling to the wireless communication transmitting or receiving device and the coupling is continuously positionable along a length of the guide rail for accommodating variable positioning of the wireless communication transmitting or receiving device about the aerial tower.

Abstract: A disk antenna (10) has a base (12). The disk antenna (10) further has a hollow post (14) which is securely fastened at a bottom distal end to the base extending upwardly therefrom. The post (14) has a post base (14A). The post base (14A) is securely connected at a bottom distal end to the base (12) and rotatably connected at a top distal end to a bottom distal end of a post head swivel (14BA) which is rotatably connected at a top distal end to a bottom distal end of a post head (14B) which is securely connected at a top distal end to the dish (16). The disk antenna (10) further has a dish (16). The dish (16) has a dish plate (16A) having a dish cone (16B) centrally located therein. The dish (16) is securely attached to a top distal end of the post (14). The disk antenna (10) further has a primary antenna (18A) which is securely fastened to the dish (16).

Abstract: The present invention relates to radio communications and in particular to antenna structures. There is a growing demand in the radio communication system market to reduce the size and cost of radio communication sites and to reduce the maintenance costs involved. Many radio communication sites are also costly and difficult to maintain especially when dealing with components of the antenna structures which are located near the top of the antenna structures. The present invention attempts to address these problems. The present invention provides an antenna structure comprising a hollow antenna mast having an inside and an outside, a movable module disposed inside the hollow antenna mast and a lifting mechanism. The movable module has at least one antenna and/or at least one RF module. The a lifting mechanism permits the raising and lowering of the movable module inside the hollow antenna mast. Furthermore, the communications equipment can be placed inside the hollow antenna mast.

Abstract: For use with an antenna tower, the antenna tower providing a mount for an active antenna that is subject to misdirection when the antenna tower sways, a system for, and method of, dynamically counteracting sway in the antenna tower. The system includes: (1) a rotation detector that senses a rotation, relative to a fixed reference plane, of a portion of the antenna tower proximate the active antenna and develops a sway signal indicative thereof and (2) antenna beam steering logic, coupled to the rotation detector, that receives the sway signal and modifies a drive signal provided to elements of the active antenna to redirect a beam projecting therefrom, the drive signal thereby compensated for the rotation to counteract the sway in the antenna tower. The system may form a portion of a wireless communications station.

Abstract: The multidimensional cellular mobile telecommunication system extends the usage of existing cellular mobile telecommunication radio frequencies allocated for ground-based communications to non-terrestrial mobile subscriber stations by adding an overlay of non-terrestrial cells of predetermined geometry and locus in space to the existing ground-based cellular cell site network. The polarization of the signals produced by the non-terrestrial antenna elements is a polarization that is different than and preferably substantially orthogonal to the polarization of the cellular radio signals produced by the ground-based antennas, such as a horizontal polarization, to thereby minimize the possibility of interference with the vertically polarized ground-based radio signals.

Abstract: A deployable and retractable, telescoping style mast assembly and method employs a plurality of tubular sections of differing diameters. The tubular sections are nested one-in-another and are slidable with respect to each other, in a telescoping manner, to provide a deployable/retractable telescoping mast assembly. Retractable pins are provided to retractably extend from a collar coupled to at least one of the tube sections. In their extended state, the retractable pins are adapted to extend through apertures provided in an adjacent tube section. The retractable pins are provided with a head at one end thereof. The head of each pin is adapted to be engaged by a guide coupled to a third tube section upon the third tube section being in a collapsed state. Upon engagement with the pin head, the guide operates to pull the pin into a retracted state so as to retract the pin out of the pin receiving aperture.

Abstract: A stowable and self-deployable array antenna includes flat, rectangular antenna panels hinged side-by-side so that when deployed they are coplanar, and they fold like an accordion for stowing. The deployed array antenna is stiffened by lateral stiffening panels hingedly attached to every other hinge between antenna panels, and to the unhinged ends of the antenna panels. Foldable longitudinal stiffening panels hinged between adjacent lateral stiffening panels. Each hinged connection includes a pair of thin spring elements, corresponding to a portion of a cylinder. The two spring elements of each hinge are spaced apart with their concave sides facing, and with the axes of the defining cylinder parallel. The hinge pivots, when the spring elements buckle, about a line orthogonal to a line extending between the cylinder axes. The hinges are used as the structural elements of self-deployable masts. The mast may have a polygonal cross-section.

Abstract: The invention relates to a structure intended to support a directional apatus such as an antenna placed substantially at the top of a mast. In addition to girders (4) orthogonal to the mast (3), a plurality of elements (12) for wind bracing are provided that extend a plane (P1) defined by the girders (4). Assuming the mast to be in the erected position, each of the wind bracing elements (12) is interposed via removable connection means (13, 14) between one end (8) of the girders, a fixed point (9), which may be at ground level, and the mast, substantially below a zone (15) of the mast (3) above which the directional apparatus (2) is supported. Each wind bracing element is connected to the fixed point (9) by at least one group of guy wires. Each group of guy wires is located in a plane that bisects the dihedron coinciding with the longitudinal (vertical) axis of the mass and passes through the axes of the guy wires.

Abstract: A UHF-TV broadcast system comprising an antenna mounted on an elevated supporting structure for broadcasting UHF-TV to a prescribed region, and a transmission line having a horizontal run leading to the supporting structure for the antenna, and a vertical run leading to the antenna, the transmission line comprising a circular non-coaxial waveguide having an inside diameter large enough to support the propagation of electromagnetic energy therethrough in at least the circular, non-coaxial TE.sub.11 mode, and a multiplicity of conductive elements extending transversely across the interior of the waveguide at intervals along the length of the waveguide perpendicular to the electric field vector of TE.sub.11 -mode energy having a desired polarization, for suppressing unwanted TE.sub.11 -mode energy that is cross-polarized relative to the desired polarization.

Abstract: The invention relates to a device for wind bracing of the vertical members of a lattice mast. It is characterized in that it is provided at its ends (5, 6) with detachable means (8, 9) for joining it to its vertical members, which in turn are provided with complementary means (10).

Abstract: A radiating antenna system (30) comprises a plurality of vertically erect secondary antennae (34) disposed in a pattern about a vertically erect primary antenna (32). An electrically conductive screen (36) which surrounds the pattern of secondary antennae (34) includes partially-buried, partially exposed electrical conductors (54) which have exposed ends (54b) thereof electrically connected to one or more above-ground, loop-forming cables (52). A series of open-ended transmission lines 70 are suspended in an essentially horizontal plane above the ground with each of the transmission lines (70) being electrically connected to a top of an associated secondary antenna (34). The secondary antennae (34) are excited in a manner whereby radiation therefrom essentially cancels sky waves radiated by the primary antenna (32).

Abstract: An omnidirectional multiple-band antenna for use with a plurality of simultaneously operating transceivers wherein a common conductor mast is excited by a plurality of stub-elements arranged therearound and each sized and spaced to excite a half-wave portion of the mast.

Abstract: A method for decreasing radiation from a guy wire located in a strong electromagnetic field is disclosed. The method comprises placing inductive impedances at regular intervals along a guy wire, each interval being less than a half wavelength long. Each inductive impedance is made greater than Z.sub.o but usually less than 5 Z.sub.o where Z.sub.o is the characteristic impedance of the span between inductances. It is shown that induced current distribution in a span between inductances has, say, a negative current in the central portion of the span and positive currents near the two ends of the span. It is this reversal of the direction of the induced current, together with low magnitude, that results in very low re-radiation. In practice the inductive impedances may be constructed by using coils in shunt with guy insulators. In some applications the inductive impedances may take a different form, for example, inductive sleeves or just coils may be used as inductances.