Murata Manufacturing Co., Ltd.

Murata Mfg. Co., Ltd.

Murana Mfg. Co. Ltd.

Kenji Asakura

Teruhisa Tsuru

Harufumi Mandai

Seiji Kanba

Koji Shiroki

Tsuyoshi Suesada

Seiji Kanaba

Toshifumi Oida

Haruhumi Mandai

A chip antenna capable of reducing the spiral pitch of an antenna line to be smaller than that of a conventional one. Conductor patterns are electrically connected sequentially in series through via holes so as to form a spiral antenna line. The antenna line has a winding axis which is arranged either in a zigzag manner or along a straight line. Adjacent wound portions have an equal diameter or width or the adjacent portions may have unequal widths. Since adjacent via holes are arranged in a staggered arrangement with each other, the distance between the adjacent via holes is larger than the spiral pitch of the antenna line, allowing the adjacent portions to be closer together than a conventional chip antenna, thereby allowing the resonance frequency to be reduced.

Chip antenna

A portable telephone includes a portable telephone body made from plastic having a receiver, a transmitter, and dial keys, and a chip antenna which is mounted on a circuit board secured at the inside of the portable telephone body and which is electrically connected to an RF section provided on the circuit board in the portable telephone. The chip antenna is disposed near the transmitter at a location where a transmitted electromagnetic signal is unlikely to be affected by the body of a person who is holding the portable telephone.

Mobile communication apparatus

An antenna device, comprising an antenna unit including basic body comprising at least one of dielectric ceramic and magnetic ceramic, at least one conductor disposed at least one of inside and on a surface of the basic body, and a feeding electrode for applying a voltage to the conductor disposed on the surface of the basic body; a mounting board on which the antenna unit is mounted; a ground part in association with the mounting board and adapted to resonate with the antenna unit; and a length in the polarization direction of a radio wave of the ground part being about &lgr;/4 or more, where &lgr; is a wavelength of the radio wave, the basic body comprising a first generally planar sheet having a plurality of spaced, first conductors formed on one major surface thereof and a second generally planar sheet having a plurality of spaced second conductors formed on one major surface thereof; the first and second generally planar sheets being laminated together to form an elongated structure wherein respective pairs of the first and second conductors are coupled to one another to form respective spiral loops of a spiral antenna so that a central axis of the spiral antenna extends generally parallel to a longitudinal direction of the elongated structure; each of the sheets being formed of a material having a permeability of 1<&mgr;<7 or a dielectric constant &egr; of 1<&egr;<130; and a feeding terminal coupled to one end of the spiral antenna so that the antenna unit forms a mono-pole antenna, the antenna unit and the ground part together functioning as a dipole antenna.

Antenna device

The present invention is directed to provide a compact chip antenna for mobile communication comprising a base member which comprises either of a material having a dielectric constant .epsilon. of 1&lt;.epsilon.&lt;130 or a material having a relative permeability .mu. of 1&lt;.mu.&lt;7, at least one conductor formed on the surface of the base member and/or inside the base member, and at least one feeding terminal provided on the surface of the substrate for applying a voltage to the conductor. The conductor comprises a metal mainly containing any one of copper, nickel, silver, palladium, platinum, or gold.

The invention provides a chip-antenna, comprising: a base member including a mounting surface and made of at least one of dielectric ceramic and magnetic ceramic; at least two conductors disposed within said base member or on a surface of said base member, at least a portion of said conductors being substantially perpendicular to the mounting surface of said base member; a feeding electrode for applying a voltage to said conductors and disposed on the surface of said base member; a ground electrode disposed at least one on the surface of and within said base member; one of said conductors being served as a first conductor, one end of which is connected to said feeding electrode; the rest of said conductor being served as a second conductor, one end of which are connected to said ground electrode; and the other end of said first conductor and the other end of said second conductor being connected.

Chip-antenna

A chip antenna in which correct evaluation and inspection of a conductor can be performed regardless of the state of grounding. The chip antenna has a rectangular-prism-shaped substrate formed of a dielectric material comprising, e.g., barium oxide, aluminum oxide and silica. A copper or copper-alloy conductor is spirally wound within the substrate in the longitudinal direction. A feeding terminal for applying a voltage to the conductor and a free terminal are disposed on the surfaces of the conductor. One end of the conductor is attached to the feeding terminal, while the other end is connected to the free terminal.

An antenna device having a power supplying portion 52 mounted on a main wiring substrate 53a and a radiating portion 56a provided in a space between the main wiring substrate 53a and the inner surface of a sheathing case 55, the lower surface of the radiating portion 56a being opposed to the power supplying portion 52.

Antenna device having a radiating portion provided between a wiring

A compact non-directional chip antenna. The chip antenna includes a rectangular-parallelopiped base made of printed circuit boards (specific inductive capacity: about 2 to 6) having a glass epoxy resin or glass fluororesin as main constituents, a conductor, made of copper or a copper alloy, which is wound in the shape of a spiral inside the base along the direction of the length of the base, and a power feeding terminal, for applying a voltage to the conductor, on the surface of the base. One end of the conductor forms a power feeding section and is connected to the power feeding terminal. The other end of the conductor forms a free end inside the base.

Antenna integral with printed circuit board

An antenna apparatus which exhibits excellent mechanical strength and which is protected from heat and moisture, and also which is mountable on a printed wiring board with the provision of a clearance between the apparatus and the board, free from deformation caused by a warp of the board. The antenna apparatus has a rectangular-prism shaped substrate. A feeding terminal and a fixing terminal are disposed at the respective end surfaces in the longitudinal direction of the substrate. Metal strips serving as support terminals are soldered at the respective first ends to the feeding terminal and the fixing terminal, respectively. A coating material formed of a non-metallic material, such as glass, resin or the like, is applied to the surface of the substrate by way of coating, dipping or other method. A coating layer is thus formed on the substrate in a state in which the respective second ends of the metal strips project from the substrate.

Antenna apparatus having a spiral conductor and a coating layer

A miniature chip antenna suitable for use in low-frequency-band mobile communications is disclosed. The chip antenna has a rectangular-prism-shaped base member provided with a mounting surface. Disposed within the base member is a conductor spirally wound along the height of the base member. The base member is formed from e.g., ferrite comprising Ni--Zn having a relative magnetic permeability of 7. The conductor is made from a metal comprising, e.g., Cu, Ni, Ag, Pd, Pt, or Au, and is formed by printing, depositing, laminating or plating. The base member and the conductor are then integrally sintered. A conductor having a rectangular cross section and spirally wound along the height of the base member is thus formed within the base member.

A helical antenna is provided in which a predetermined resonance frequency can be determined at the design stage. The helical antenna includes a conductor which is formed from copper or a copper alloy inside a base in the shape of a rectangular parallelopiped formed from a dielectric material having barium oxide, aluminum oxide and silica as main constituents and which is wound in a helical shape along the length of the base. In such a case, the resonance frequency f0 of the helical antenna and the inductance components L of the conductor satisfy the relationship: ln (L)=A0+A1.times.ln (f0), where ln is a natural logarithm, and A0 and A1 are constants. One end of the conductor is extended onto the surface of the base and forms a power feeding terminal connected to a power feeding terminal formed on the surface of the base for applying a voltage to the conductor, and the other end thereof forms a free end inside the base.

Helical antenna and method of making same

An antenna device is provided in which deterioration of characteristics is prevented and which has improved strength. A chip antenna is inserted into a resin case serving as a support member, and one terminal of the resin case is bonded to a power feeding terminal and another terminal of the case is bonded to a fixation terminal of the chip antenna 2 by solder. The chip antenna is fixed to the resin case so that a gap is provided between the printed circuit board on which the chip antenna is mounted and the chip antenna. Then, by bonding the terminals of the resin case to the printed circuit board by solder, the chip antenna is mounted on the printed circuit board.

A surface mount antenna having increased mechanical strength, and whose properties do not deteriorate when exposed to heat and moisture. The surface mount antenna includes a substrate, and a conductive portion in or on the substrate, with an electrical supply terminal formed on a surface of the substrate in order to apply voltage to the conductive portion. A covering material is provided to cover the substrate by coating, dipping, or the like.

Surface mount antenna

A chip antenna in which desired antenna characteristics can be obtained without restricting the type of at least one of a dielectric material and a magnetic material used for a base member of the antenna, as well as the type of metal material used for a conductor, or without limiting the sintering conditions of the above-described materials. The chip antenna includes a rectangular-prism-shaped base member having a mounting surface. A conductor, e.g. silver, is spirally wound inside the base member. A feeding terminal is formed over surfaces of the base member so as to feed power to the conductor. One end of the conductor is extended to a surface of the base member to form a feeding section, which is connected to the feeding terminal. The other end of the conductor serves as a free end within the base member. The base member is produced by laminating mixture layers made from a mixture of glass essentially consisting of borosilicate having a softening point of approximately 700.degree. C. and ceramic (relative dielectric constant: 60) essentially consisting of barium oxide, neodymium oxide and titanium oxide having a sintering temperature of approximately 1300.degree. C.

Chip antenna and method of making same

A meander line antenna includes a rectangular-parallelopiped base member made from a dielectric material having barium oxide, aluminum oxide, and silica as main components, a meander-shaped conductor having, e.g., 10 corners made of copper or a copper alloy by printing, deposition, pasting, or plating inside the base member, and a power-feed terminal for applying a voltage to the conductor. The meander-shaped conductor is formed in the longitudinal direction of the base member. One end of the conductor is led to a surface of the base member to form a power-feed section and is connected to the power-feed terminal. The other end of the conductor serves as an open end inside the base member.

Growing community of inventors

Shiga-ken, Japan

Kenji Asakura