Abstract: A wide beamwidth antenna system (100) having a number of monopole antenna elements (102-108) disposed on at least one surface (111,113) of a single, flexible dielectric substrate (101), a number of antenna feed members (110-116), disposed on the first surface (111) of the dielectric substrate (101), each antenna feed member (110-116) being respectively coupled to one of the monopole antenna elements (102-108), a system feed member (118), disposed on the first surface (111) of the dielectric substrate (101), a first power splitter (120), disposed on the first surface (111) of the dielectric substrate (101) and coupled between the system feed member (118) and the first one of the monopole antennae (102) and a first phase shifter (130), disposed on the first surface (111) of the dielectric substrate (101) and coupled between the first (102) and the second (104) monopole antennae. A ground plane (140) is disposed on a portion of the second surface (113) of the dielectric substrate (101).

Abstract: An energy diversity antenna (100) includes a first antenna (103) and second antenna (113) positioned on a substrate (101). The first antenna is preferably a loop used for receiving radio frequency signals with H-field energy while the second antenna is preferably a monopole used for receiving radio frequency signals with E-field energy. The energy diversity antenna (100) is applicable for use in portable communications devices capable of diversity reception. It is particularly useful in geographic locations where reflections and multipath interference is a problem.

Abstract: An antenna (100) includes a quarter-wave monopole radiating element (110, 110') having a signal feed point end (110A). The antenna (100) further includes a reactive element (150) in the form of a conductive sleeve. The sleeve (150) includes a grounding end (150A) and is coaxially positioned around a portion of the monopole radiating element (110, 110'). A spacer (140) is coaxially situated between the monopole radiating element (110, 110') and the reactive element (150), for electrically insulating the monopole radiating element (110, 110') from the reactive element (150). The spacer (140) is sufficiently dimensioned such that the monopole radiating element is tightly coupled to the reactive element (150) at substantially around the feed point end (150A).

Abstract: A combination battery pack and low profile antenna arrangement for use in conjunction with a two-way portable transceiver includes an enclosure containing an electrical battery with positive and negative electrodes. A pair of terminals are attached to the outer surface of the enclosure and are coupled to the positive and negative electrodes. A low profile antenna structure is disposed within the enclosure and includes a feed point for coupling RF energy to and from the antenna structure. An antenna coupling arrangement is electrically coupled to the feed point for coupling RF energy into and out of the enclosure.

Abstract: An antenna with a first and second portions (16 and 18) that are rotatably movable with respect to each other. The antenna may be rotated from a first position to a second position and from the second position to the first position so that it operates as two antennas while in the first position and as a loop antenna while in the second position.

Abstract: A laminar antenna includes a conductive ground plane (102), a first dielectric lamina (106), a conductive exciter lamina (108), a second dielectric lamina (114), and a conductive radiator lamina (116). The radiator partially overlaps the exciter and the amount of overlap determines the input impedance of the antenna. The laminar antenna can be positioned within the wall of a plastic radio housing (302). Multi-radiator wideband and duplex embodiments of the antenna are also described. In another embodiment, the ground plane extends above the radio housing while the radiator and dielectric laminae wrap around the extended portion of the ground plane.

Abstract: An antenna is provided which includes a half wave helical element RF coupled to a monopole element. The monopole element is situated on the axis of the helical element and extends into the helical element a distance sufficient to permit resonant coupling between the helical element and the monopole element. The monopole element is driven by a source of radio frequency energy such that the helical element coupled thereto is excited by such radio frequency energy.

Abstract: An antenna is provided which includes first and second helical elements which are separated by a dielectric spacer. The first helical element is fed a radio frequency driving signal and the remaining second element is coupled to ground. The first and second elements are coupled together in a fashion which results in a dramatic increase in antenna bandwidth in comparison to prior helical antennas.

Abstract: A low profile antenna comprised of a driven element and a parasitic element spaced above a ground plane. The driven element is connected at one end to the feedpoint of the radio device to which it is attached, the opposite end thereof being free. The parasitic element is connected to the ground plane by its end nearest the feedpoint, the opposite end thereof being free. In the preferred embodiment the parasitic element length and the driven element length are both approximately equal to a quarter wavelength at the operating frequency.

Abstract: A low profile antenna comprised of a driven element and a parasitic element spaced above a ground plane. The driven element is connected at one end to the feedpoint of the radio device to which it is attached, the opposite end thereof being free. The parasitic element is connected to the ground plane by its end nearest the feedpoint, the opposite end thereof being free. In the preferred embodiment the parasitic element length and the driven element length are both approximately equal to a quarter wavelength at the operating frequency.

Abstract: A coaxial dipole antenna includes a first radiator which is approximately one quarter wavelength long. A second radiator exhibits length less than one quarter wave length and is coupled to the feed port by a reactive element which has an electrical reactance which is insufficient to increase the electrical length of the second radiator to one quarter of the wavelength. The length of a dipole antenna is substantially shortened while an effective aperture of one half wavelength is maintained by causing a portion of the transceiver housing to radiate in phase with the antenna.

Abstract: An antenna is provided which exhibits a low profile. The antenna includes a counterpoise of electrically conductive material and a passive element oriented substantially parallel thereto. The ends of the passive element are electrically coupled to the counterpoise surface. An active element of electrically conductive material includes a middle portion and first and second outer end portions. The middle portion is situated adjacent and spaced apart from the passive element by a predetermined distance and in a parallel relationship therewith. The first outer end portion of the active element is bent toward the grounded end of the passive element nearest thereto. The first outer end portion represents a feedpoint of the antenna with respect to the counterpoise. The remaining second outer end portion the active element is bent towards the remaining end of the passive element nearest thereto.

Abstract: An antenna is provided which exhibits an overall shortened length with respect to the length of the conventional sleeve dipole type antenna. The antenna includes an upper radiating element coupled to a tank circuit to induce resonance at a first resonant frequency and further includes a helical element electrically coupled to a sleeve member which cooperate to resonate at a second resonant frequency.

Abstract: An antenna is provided which exhibits a relatively small size and is capable of resonating at two different frequencies. The antenna includes two helically wound elements which resonate at a first resonant frequency. A conductive member extends through and beyond one of the two helical elements to cause the antenna to resonate at a second resonant frequency.

Abstract: A dual mode antenna for a miniature radio transceiver includes a low profile loop antenna structure while mounted on a body and a high efficiency dipole antenna while held in the hand.