Abstract: A ring antenna has a C-shaped loop element formed on the upper surface of a main body part including a ring-shaped dielectric material having a square cross-sectional shape. A cut part is formed in a portion of this C-shaped loop element, which is formed in the shape of a loop. In addition, an arc-shaped radiation element is formed on the inner circumferential surface of the main body part so as to be concentric with the C-shaped loop element, with a prescribed interval therebetween. The C-shaped loop element is excited by the radiation element. The tip of a feed conductor is connected to a feed part that is connected to one end of the radiation element formed on the lower surface of main body part, and electrical power is fed to the radiation element from the feed conductor.

Abstract: An antenna apparatus that can suppress sensitivity degradation as much as possible to receive AM broadcasts and FM broadcasts even if an antenna height is decreased to 70 mm or less. An antenna board is vertically mounted on a planar antenna base, and a top portion is disposed to stride over the antenna board. An antenna element includes the top portion and an antenna pattern formed on the antenna board. A distance between the antenna base and a lower edge of the top portion is not less than 10 mm, and the lower edge of the top portion is bent downward. The top portion is configured such that an antenna capacitance of the antenna element becomes about 3 pF or more. A received signal from the antenna element is guided to an amplifier board through a connecting wire and amplified. An antenna case is fitted in the antenna base.

Abstract: A helical element, which is operated in the frequency band of FM broadcast, is wound around the outer periphery of a rod-shaped support member 10. A line-shaped element 12, which is operated in the frequency band of terrestrial digital television broadcast, is disposed in a first groove 10a of a predetermined length formed on the outer periphery of the support member 10 from the lower end thereof. With this arrangement, a multi-frequency antenna 1, which is operated in the frequency band of FM broadcast and the frequency band of terrestrial digital television broadcast, can be arranged, and the entire length L of the helical element can be reduced and it can be operated in a plurality of frequency bands with the effect of the line-shaped element 12.

Abstract: The present invention provides a dual-band antenna that can be operated at two frequencies without providing the choke coil. A first element operated in a high-frequency-side band is formed in a surface of a print board using a print pattern. A second element operated in a low-frequency-side band is formed in an upper portion of a rear surface of the print board so as not to overlap the first element. A power is fed to the first element from a power feeding point located at a lower end of the print board, and the power is fed to the second element through a throughhole made in a middle of the first element. The power is fed to the second element from the throughhole through a long and thin power feeding line, and the power feeding line exhibits a high impedance to a high frequency. A slit is formed in the first element corresponding to the power feeding line.

Abstract: Even though an antenna apparatus is low profile to have a height of not more than 70 mm, sensitivity is maximally suppressed from being deteriorated. In an antenna case 10 projecting from a vehicle in a height of not more than 70 mm, an antenna circuit board 30 on which an antenna pattern is formed is uprightly arranged and an amplifier circuit board 34 which amplifies a received signal output from the antenna circuit board 30 are housed. In the antenna circuit board 30, an antenna coil to resonate the antenna pattern in an FM waveband is inserted between the antenna pattern and a feeding point. Therefore, a low-profile antenna pattern having a length which is about 1/20 a wavelength of an FM broadcast resonates the FM band.

Abstract: A wideband antenna including a ground element, and an antenna body provided on the ground element with a predetermined distance. The antenna body includes a feed element and a dielectric substrate, wherein an annular passive element is provided on the top surface of the dielectric substrate with a predetermined gap from the feed element. A plural short-circuit pins are equally spaced on the outer periphery of the passive element, whereby the passive element and the ground element 17 are connected by the short-circuit pins. A slit is formed on the passive element in the vicinity of the short-circuit pins. Since the slit is formed on the passive element, a resonance circuit having a resonance frequency dependant on the shape of the slit is formed on the passive element in the vicinity of the slit, whereby the radiation of the frequency component from the feed element is prevented.

Abstract: An antenna apparatus that can suppress sensitivity degradation as much as possible to receive AM broadcasts and FM broadcasts even if an antenna height is decreased to 70 mm or less. An antenna board is vertically mounted on a planar antenna base, and a top portion is disposed to stride over the antenna board. An antenna element includes the top portion and an antenna pattern formed on the antenna board. A distance between the antenna base and a lower edge of the top portion is not less than 10 mm, and the lower edge of the top portion is bent downward. The top portion is configured such that an antenna capacitance of the antenna element becomes about 3 pF or more. A received signal from the antenna element is guided to an amplifier board through a connecting wire and amplified. An antenna case is fitted in the antenna base.

Abstract: The present invention provides a dual-band antenna that can be operated at two frequencies without providing the choke coil. A first element operated in a high-frequency-side band is formed in a surface of a print board using a print pattern. A second element operated in a low-frequency-side band is formed in an upper portion of a rear surface of the print board so as not to overlap the first element. A power is fed to the first element from a power feeding point located at a lower end of the print board, and the power is fed to the second element through a throughhole made in a middle of the first element. The power is fed to the second element from the throughhole through a long and thin power feeding line, and the power feeding line exhibits a high impedance to a high frequency. A slit is formed in the first element corresponding to the power feeding line.

Abstract: Good electric characteristics are obtained even after an antenna being further incorporated into an antenna apparatus including an antenna case having a limited space. An antenna device 31 is formed on an antenna substrate installed upright in an antenna base 20. A flat antenna unit is fastened to the antenna base 20 so that the flat antenna unit 35 is immediately below the antenna device 31. If the wavelength of a center frequency in an operating frequency band of the flat antenna unit 35 is ?, an interval between an upper surface of the flat antenna unit 35 and a lower end of the antenna device 31 is set to about 0.25? or more. Accordingly, it becomes possible to make directional characteristics of radiation in a horizontal plane of the flat antenna unit 35 non-directive without being affected by the antenna device 31 and also to achieve good gain characteristics.

Abstract: No coupled effects occur even when a plurality of antennas is provided. An insert fitting 12 is formed integrally with an antenna cover such that the insert fitting 12 is arranged overhead of a patch antenna 13 in a position where the gap h satisfies h<<?/4. Further, the width D of the insert fitting 12 and an antenna element 10 secured to the insert fitting 12 is set so as to satisfy D<<?/4, and the insert fitting 12 and the antenna element 10 are extended upwards at a slant. An effect on the emission pattern and electric characteristics of the patch antenna 13 can thereby be prevented even if the antenna element 10 and the insert fitting 12, which are metal conductors, are arranged in proximity to the patch antenna 13.

Abstract: A helical element, which is operated in the frequency band of FM broadcast, is wound around the outer periphery of a rod-shaped support member 10. A line-shaped element 12, which is operated in the frequency band of terrestrial digital television broadcast, is disposed in a first groove 10a of a predetermined length formed on the outer periphery of the support member 10 from the lower end thereof. With this arrangement, a multi-frequency antenna 1, which is operated in the frequency band of FM broadcast and the frequency band of terrestrial digital television broadcast, can be arranged, and the entire length L of the helical element can be reduced and it can be operated in a plurality of frequency bands with the effect of the line-shaped element 12.

Abstract: Even though an antenna apparatus is low profile to have a height of not more than 70 mm, sensitivity is maximally suppressed from being deteriorated. In an antenna case 10 projecting from a vehicle in a height of not more than 70 mm, an antenna circuit board 30 on which an antenna pattern is formed is uprightly arranged and an amplifier circuit board 34 which amplifies a received signal output from the antenna circuit board 30 are housed. In the antenna circuit board 30, an antenna coil to resonate the antenna pattern in an FM waveband is inserted between the antenna pattern and a feeding point. Therefore, a low-profile antenna pattern having a length which is about 1/20 a wavelength of an FM broadcast resonates the FM band.

Abstract: A planar antenna fitted with a reflector of small shape and small depth. A reflector 21 of planar shape is provided at the rear face of a radiator 20 of planar shape made of a triangular loop element. The side sections 21b on both sides of the reflector 21 are bent towards the radiator 20 and the separation .alpha.2 between the leading edges of the side sections 21b and the side edges of the radiator 20 is thereby reduced. In this way, an excellent electrical characteristic of the planar antenna 2 fitted with a reflector and can be achieved by reducing the separation D2 of the radiator 20 and reflector 21.

Abstract: Even though an antenna apparatus is low profile to have a height of not more than 70 mm, sensitivity is maximally suppressed from being deteriorated. In an antenna case 10 projecting from a vehicle in a height of not more than 70 mm, an antenna circuit board 30 on which an antenna pattern is formed is uprightly arranged and an amplifier circuit board 34 which amplifies a received signal output from the antenna circuit board 30 are housed. In the antenna circuit board 30, an antenna coil to resonate the antenna pattern in an FM waveband is inserted between the antenna pattern and a power supply point.

Abstract: A signal divider 1 can be miniaturized in which divided signals do not interfere with each other and, at the same time, DC power does not creep into each other. Since a signal dividing circuit 11 is a lumped constant circuit and each element can be made as a chip element, the signal divider 1 can be miniaturized. A division ratio of divided signal output from a first division output terminal OUT1 and a second division output terminal OUT2 can be set by a circuit A and a circuit B. Since a circuit C is connected in parallel with a series circuit composed of the circuit A and the circuit B to produce resonance at a usage frequency, a sufficient amount of isolation between the first division output terminal OUT1 and the second division output terminal OUT2 can be guaranteed. DC power supplied from the first division output terminal OUT1 and the second division output terminal OUT2 can be prevented from creeping out by the capacitors C2, C4.

Abstract: An object of the present invention is to provide a simple, reasonably-priced patch antenna which can be assembled easily. A pair of first L-shaped holding portions 14b formed on a spacer 14 is inserted into a pair of attachment holes 12c formed in an antenna plate 12, and the antenna plate 12 is slid so that the upper portions of the attachment holes 12c in the antenna plate 12 are gripped between the upper portions of the first L-shaped holding portions 14b and a spacer main body 14a. As a result, the antenna plate 12 is fixed to the spacer 14. Next, a pair of second L-shaped holding portions 14e is inserted into a pair of insertion holes 13d formed in a ground plate 13, and the ground plate 13 is slid so that the lower portions of the insertion holes 13d in the ground plate 13 are gripped between the upper portions of the second L-shaped holding portions 14e and the spacer main body 14a. As a result, the ground plate 13 is fixed to the spacer 14.

Abstract: With the object of forming a compact antenna that operates in a plurality of frequency bands, the pattern of an antenna element (14) that can resonate in a plurality of frequency bands is formed on the outer circumferential surface of an antenna bobbin (12). A parasitic conductor (11) is inserted into an accommodating hole, which is formed substantially along the central axis of this antenna bobbin (12). As a result, an antenna that operates favorably in the frequency bands of AMPS, PCS and GPS can be obtained.

Abstract: An object of the present invention is a small composite antenna that is capable of operating in a plurality of different frequency bands. A first antenna 2 constituting a GPS circularly polarized loop antenna is formed on a dielectric substrate 10. A second antenna 3 constituting an ETC square patch antenna is formed on substantially the same axis as the first antenna 2. An earth pattern is formed in the underside of the dielectric substrate 10, and a recess in whose bottom face an earth pattern is formed so as to lie opposite the second antenna 3 is provided. An arc-shaped feed pattern 4 is electromagnetically coupled to the first antenna 2 so as to supply electricity thereto, whereby this antenna is made to operate as a right-handed circularly polarized antenna. Electricity is supplied by a coaxial cable to the second antenna 3 to cause same to operate as a right-handed circularly polarized antenna.

Abstract: An object of the present invention is to provide a small composite antenna that is capable of operating in a plurality of different frequency bands. A GPS first loop antenna 2 is formed on a dielectric substrate 10. A VICS radio wave beacon second loop antenna 3 is formed on substantially the same axis within the first loop antenna 2. In addition, an ETC patch antenna 4 is formed in the bottom face of a recess 12 provided substantially in the center of the dielectric substrate 10. An earth pattern is formed over the whole of the underside of the dielectric substrate 10. An arc-shaped first feed pattern is electromagnetically coupled to the first loop antenna 2 so as to supply electricity thereto and cause same to operate as a right-handed circularly polarized antenna. An arc-shaped second feed pattern is electromagnetically coupled to the second loop antenna 3 so as to supply electricity thereto.

Abstract: With the object of providing a mobile wireless equipment with a multi-frequency antenna capable of performing communication with a GPS system in addition to conventional communication with mobile wireless systems, an antenna 10 for mobile wireless equipment and a GPS antenna 4 are tightened together by threading an antenna fixing nut 19 onto a holder 7 from within a casing 101, after inserting a holder 7 of the antenna 10 for mobile wireless equipment from above a through-hole 4b of the GPS antenna 4 and inserting the holder 7, which projects from below, from above into an aperture 101a of the casing 101. Also, positioning and fixing of the GPS antenna 4 are performed by engagement of claws 41, 41 formed on the GPS antenna 4 and a positioning boss 42 with claw receiving sections 43, 43 and a boss receiving section 44 formed in the upper part of the casing 101.