Murata Manufacturing Co., Ltd.

Naoki Gochi

Noboru Kato

Jun Sasaki

Katsumi Taniguchi

In antenna device, a coil conductor of an antenna coil module and a conductor layer at least partially overlap. A current flows in the conductor layer to block a magnetic field generated by a current flowing in the coil conductor. A current flows along the periphery of a slit and around the periphery of the conductor layer due to a cut-edge effect. Since magnetic flux does not pass through the conductor layer, magnetic flux attempts to bypass the conductor layer along a path in which the conductor opening of the conductor layer is on the inside and the outer edge of the conductor layer is on the outside. As a result, the magnetic flux generates large loops that link the inside and the outside of a coil conductor of an antenna on a reader/writer side to couple an antenna device and the antenna on the reader/writer side.

Antenna device and method of setting resonant frequency of antenna device

In antenna device, a coil conductor of an antenna coil module and a conductor layer at least partially overlap. A current flows in the conductor layer to block a magnetic field generated by a current flowing in the coil conductor. A current, which flows around the periphery of an opening of the conductor layer, flows along the periphery of a slit and around the periphery of the conductor layer due to a cut-edge effect. Since magnetic flux does not pass through the conductor layer, magnetic flux attempts to bypass the conductor layer along a path in which the conductor opening of the conductor layer is on the inside and the outer edge of the conductor layer is on the outside. As a result, the magnetic flux generates relatively large loops that link the inside and the outside of a coil conductor of an antenna on a reader/writer side.

Growing community of inventors

Nagaokakyo, Japan

Naoki Gochi