Murata Manufacturing Co., Ltd.

Takafumi Nasu

Kenichi Ishizuka

Kentaro Mikawa

Tatsuya Hosotani

Katsumi Taniguchi

Makoto Takeoka

Shinya Tachibana

Masaaki Kanao

An antenna device includes first and second radiating elements, a first coil coupled to the first radiating element or a feeding circuit, a second coil coupled to the second radiating element and coupled to the first coil via an electromagnetic field, and an inductor. The first and second radiating elements are coupled to each other via an electric field. The harmonic resonant frequency of a resonance circuit defined by a transformer defined by the first coil and the second coil, the inductor, and the second radiating element exists within a communication frequency range. The harmonic resonant frequency is a (2n+1)th harmonic frequency, where n is an integer equal to or greater than 1.

Antenna device and communication terminal apparatus

An antenna device includes first and second antennas. The first antenna includes a first radiating element connected to a feed circuit to supply a radio-frequency signal, and a first coil connected between the first radiating element and the feed circuit. The second antenna includes a second coil magnetically coupled to the first coil, and a second radiating element connected to the second coil. An impedance of the first antenna is higher than about 50Ω at a resonant frequency of a fundamental of the second antenna.

Antenna device and communication terminal device

An antenna device includes a radiating element, a coupling circuit, and a non-radiating resonant circuit. The coupling circuit includes first and second coupling elements, the first coupling element being connected between a feeder circuit and the radiating element, the second coupling element being coupled to the first coupling element. An end of the second coupling element is grounded, and another end of the second coupling element is connected to the non-radiating resonant circuit. A frequency characteristic of a return loss of the radiating element when seen from the feeder circuit is adjusted by a resonant frequency characteristic of the non-radiating resonant circuit.

Antenna device and electronic equipment

An antenna coupling element includes a first coil connected to a first radiating element and a feeder circuit and a second coil connected to a second radiating element and electromagnetically coupled to the first coil. The first and second coils have a relationship in which a direction of a magnetic field generated in the first coil when a current flows from the first coil toward the first radiating element and a direction of a magnetic field generated in the second coil when a current flows from the second coil toward the second radiating element are opposite to each other. The first and second coils are set such that a resonant frequency of a fundamental wave of the second radiating element with a transformer defined by the first coil and the second coil is lower than a resonant frequency of a fundamental wave of the first radiating element.

Antenna coupling element, antenna device, and communication terminal device

An antenna device includes a first radiating element, a second radiating element having lower radiation efficiency than the first radiating element, a coupling element including first and second coils that are electromagnetically coupled to each other, and first and second phase adjusting elements. The first and second phase adjusting elements induce, at a resonant frequency of the second radiating element, a predetermined proportion of current flowing through the second radiating element to the first radiating element.

Antenna device and electronic apparatus

An antenna apparatus includes first and second antennas. First and second radiating elements include parallel extending portions. A first coil is connected between the first radiating element and a first feed circuit connection portion. A second coil is connected between the second radiating element and a ground conductor. The first and second coils are coupled to each other in additive polarity. A phase adjustment circuit adjusts a phase difference between currents respectively flowing through the first and second radiating elements to greater than or equal to about 90 degrees and less than about 180 degrees in a communication frequency band of the second antenna. Where a frequency of a fundamental of the first radiating element is f1 and a frequency of a fundamental of the second radiating element is f2, f1&#x3e;f2, and 3f2&#x2212;f1&#x3e;f1&#x2212;f2 are satisfied.

Antenna apparatus

An antenna unit includes a coupling element including first and second coils, a feeding radiating element, and a parasitic radiating element. A series circuit including the first coil and a feeder circuit is connected to the feeding radiating element, and the parasitic radiating element is connected to the second coil. A distance between open ends of the parasitic radiating element and a short portion of the feeding radiating element is shorter than a distance between open ends of the parasitic radiating element and a long portion the feeding radiating element. The antenna unit is an antenna for a first frequency band with fundamental wave resonance of the long portion and fundamental wave resonance of the parasitic radiating element, and a second frequency band with higher-order resonance of the parasitic radiating element and resonance of the short portion, the second frequency band being higher than the first frequency band.

Antenna unit and electronic device

An antenna device includes first and second radiating elements, a first coil coupled to the first radiating element or a feeding circuit, and a second coil coupled to the second radiating element and coupled to the first coil via an electromagnetic field. The first and second radiating elements are coupled to each other via an electric field. At a resonant frequency defined by the antenna coupling element and the second radiating element, the absolute value of the phase difference between a current flowing into the second radiating element due to the electromagnetic field of the first coil and the second coil and a current flowing into the second radiating element due to the electric field is equal to or less than about 90 degrees.

A magnetic field coupling element includes conductor patterns stacked with insulating layers interposed therebetween, and interlayer connection conductors that inter-connect the conductor patterns at predetermined positions. The conductor patterns include first, second, third, and fourth conductor patterns, and the interlayer connection conductors include first and second interlayer connection conductors. The first conductor pattern, the second conductor pattern, and the first interlayer connection conductor define a first coil, and the third conductor pattern, the fourth conductor pattern, and the second interlayer connection conductor define a second coil. The first coil and the second coil are disposed in a region of less than about &#x2153; of a stacking height of a multi-layer body including the insulating layers.

Magnetic field coupling element, antenna device, and electronic equipment

A wireless module includes a substrate that includes a first portion, a second portion, and a first flexible portion connecting the first portion and the second portion to each other. The first portion includes a circuit element that is mounted on the first main surface and a circuit including at least the circuit element. The second portion includes a first coil connected to the circuit. The first portion and the second portion face each other. A magnetic sheet is disposed on a second main surface of the second portion, and a battery is disposed between the second main surface of the first portion and the magnetic layer.

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Nagaokakyo, Japan

Takafumi Nasu