Abstract: A monopole antenna is formed of a ground plane, a flat conductor faced to the ground plane and separated from it by a clearance “H”, and a linear conductor that is connected to the flat conductor, extended on the ground plane side in an insulated state from the ground plane, and connected to a signal source. The flat conductor is formed of an inner conductor, and outer conductors disposed on the outer periphery of the inner conductor at a predetermined interval. Set regions of the outer edge of the inner conductor and the inner edges of the outer conductors are interconnected through one or more coupling conductors.

Abstract: On the top surface of conductive ground plate, first holder having first antenna element, second holder having second antenna element, and support having parasitic antenna element are provided such that holders and support confront each other. Respective intermediate sections of antenna elements are folded to shape like “square C” in plural times, so that antenna is formed. The foregoing construction allows low-profiling and downsizing antennas to be used in mobile radio devices.

Abstract: A composite antenna has a conductor ground plate having a preset shape, a plurality of antenna elements faced to each other and separated from the conductor ground plate by predetermined element interval, and feeding terminals for feeding power to the antenna elements via transmission lines in the same phase. The antenna elements and the feeding terminals are disposed symmetrically with respect to the center of the conductor ground plate. Even when the number of operating frequencies is increased to three or more, the composite antenna is thin and small and can provide a predetermined directional characteristic.

Abstract: The antenna of the present invention comprises flat-plate conductive ground plane 1, first antenna element 13 with one end 13a connected to feeding point 2 and intermediate portion 13b folded by a plurality of times, which is extended upward from the ground plane 1, and second antenna element 23 with one end 23a connected to the other end 13c of the first antenna element 13, with intermediate portion 23b formed in symmetrical relation to the first antenna element 13, and also, with the other end 23c connected to the ground plane 1. Thus, it is possible to obtain a small size antenna with the antenna element lowered in height.

Abstract: A monopole antenna is formed of a ground plane, a flat conductor faced to the ground plane and separated from it by a clearance “H”, and a linear conductor that is connected to the flat conductor, extended on the ground plane side in an insulated state from the ground plane, and connected to a signal source. The flat conductor is formed of an inner conductor, and outer conductors disposed on the outer periphery of the inner conductor at a predetermined interval. Set regions of the outer edge of the inner conductor and the inner edges of the outer conductors are interconnected through one or more coupling conductors.

Abstract: A monopole antenna is formed of a ground plane, a flat conductor faced to the ground plane and separated from it by a clearance “H”, and a linear conductor that is connected to the flat conductor, extended on the ground plane side in an insulated state from the ground plane, and connected to a signal source. The flat conductor is formed of an inner conductor, and outer conductors disposed on the outer periphery of the inner conductor at a predetermined interval. Set regions of the outer edge of the inner conductor and the inner edges of the outer conductors are interconnected through one or more coupling conductors.

Abstract: An antenna element includes a conductive ground plane, planar first and second antenna elements, and feeding points. The first antenna element confronts the ground plane at a given interval, and the second antenna element surrounds parts of the outer periphery of the first antenna element at a certain interval. Each one of the feeding points is provided to the first and the second antenna elements for feeding high-frequency signals to those elements. The foregoing construction allows achieving a compact antenna device that can perform a polarization diversity communication.

Abstract: An antenna element includes a conductive ground plane, planar first and second antenna elements, and feeding points. The first antenna element confronts the ground plane at a given interval, and the second antenna element surrounds parts of the outer periphery of the first antenna element at a certain interval. Each one of the feeding points is provided to the first and the second antenna elements for feeding high-frequency signals to those elements. The foregoing construction allows achieving a compact antenna device that can perform a polarization diversity communication.

Abstract: On the top surface of conductive ground plate, first holder having first antenna element, second holder having second antenna element, and support having parasitic antenna element are provided such that holders and support confront each other. Respective intermediate sections of antenna elements are folded to shape like “square C” in plural times, so that antenna is formed. The foregoing construction allows low-profiling and downsizing antennas to be used in mobile radio devices.

Abstract: Monopole antenna 40 of the present invention is formed of ground plane 1, flat conductor 10 faced to ground plane 1 and separated from it by clearance “H“, and linear conductor 3 that is connected to flat conductor 10, extended on the ground plane 1 side in an insulated state from ground plane 1, and connected to a signal source. Flat conductor 10 is formed of inner conductor 11, and outer conductors 12 and 13 disposed on the outer periphery of inner conductor 11 at a predetermined interval. Set regions of the outer edge of inner conductor 11 and the inner edges of outer conductors 12 and 13 are interconnected through one or more coupling conductors 311, 312, 321 and 322.

Abstract: An inverted-F type antenna and a wireless device using the same. The antenna element comprises a grounding conductor plate and a conductor at least a part of which is generally spiral in shape and is disposed above the grounding conductor plate apart from the grounding conductor plate. A stub connects one end of the antenna element with the grounding conductor plate. A feeding point locates on the antenna element at a predetermined distance from one end of the antenna element and a feeder line electrically connects the feeding point with an external circuit. The antenna element is secured on the grounding conductor plate with a support member made of a dielectric material.

Abstract: A composite antenna of the present invention has conductor ground plate 12 having a preset shape, a plurality of antenna elements 16 faced to each other and separated from conductor ground plate 12 by predetermined element interval 220, and feeding terminals 15 for feeding power to antenna elements 16 via transmission lines in the same phase. Antenna elements 16 and feeding terminals 15 are disposed symmetrically with respect to the center of conductor ground plate 12. Even when the number of operating frequencies is increased to three or more, the composite antenna is thin and small and can provide a predetermined directional characteristic.

Abstract: A top-loading monopole antenna apparatus having a feeding point is provided for use in a communication system such as a mobile communication system or the like. The top-loading monopole antenna apparatus includes a grounding conductor, a top-loading electrode, a linear conductor element, and a short-circuit conductor. The grounding conductor is provided so as to oppose the grounding conductor. The linear conductor element electrically connects the feeding point with the top-loading electrode, and the short-circuit conductor electrically connects the top-loading electrode through a reactive element. This antenna structure leads to a height which is lower than that of prior art, and easy impedance matching.

Abstract: The antenna of the present invention comprises flat-plate conductive ground plane 1, first antenna element 13 with one end 13a connected to feeding point 2 and intermediate portion 13b folded by a plurality of times, which is extended upward from the ground plane 1, and second antenna element 23 with one end 23a connected to the other end 13c of the first antenna element 13, with intermediate portion 23b formed in symmetrical relation to the first antenna element 13, and also, with the other end 23c connected to the ground plane 1. Thus, it is possible to obtain a small size antenna with the antenna element lowered in height.

Abstract: A top-loading monopole antenna apparatus having a feeding point is provided for use in a communication system such as a mobile communication system or the like. The top-loading monopole antenna apparatus includes a grounding conductor, a top-loading electrode, a linear conductor element, and a short-circuit conductor. The grounding conductor is provided so as to oppose to the grounding conductor. The linear conductor element electrically connects the feeding point with the top-loading electrode, and the short-circuit conductor electrically connects the top-loading electrode through a reactive element. This antenna structure leads to a height lower than that of prior art, and easy impedance matching.

Abstract: An inverted-F type antenna and a wireless device using the same. The antenna element comprises a grounding conductor plate and a conductor at least a part of which is generally spiral in shape and is disposed above the grounding conductor plate apart from the grounding conductor plate. A stub connects one end of the antenna element with the grounding conductor plate. A feeding point locates on the antenna element at a predetermined distance from one end of the antenna element and a feeder line electrically connects the feeding point with an external circuit. The antenna element is secured on the grounding conductor plate with a support member made of a dielectric material.

Abstract: Preparations of piece parts used in coupling a joint and a feeding fixture together and the assembly work involved are made easy and a less expensive antenna can be realized. The antenna disclosed here includes a case of a wireless device, a holder mounted on the case, a first antenna element accommodated in the holder so as to be freely movable by sliding, a stopper coupled with one end of the first antenna element and connected electrically to the holder by sliding, a cylindrical column like joint formed of an insulating resin and fixed to the other end of the first antenna element, a tubular feeding fixture formed of a metal, electrically connected with the holder by sliding and put in place sheathing the joint, and a second antenna element electrically connected to one end of the feeding fixture.

Abstract: A helical coil and a top-helical type antenna using the same, wherein the helical coil has a plurality of either substantially U-shaped or nearly V-shaped branch portions made of a thin metallic sheet material. The branch portions are connected continuously in a manner to place their open ends alternately inversely, and the branch portions alternatively curve toward an obverse side and a reverse side of the metallic sheet to form each turn of the coil. A method for producing the helical coil includes continuously die cutting a member on a belt-shaped strip of electrically conductive metallic sheet, and alternately placing a plurality of either substantially U-shaped or substantially V-shaped branch portions with their open ends inversely. These substantially U or V-shaped branch portions are then connected with each other in the shape of a letter, with connection to the metallic sheet being held only by linkage portions at opposite sides.