An antenna device is provided as a near-field communication antenna device that is configured by arranging a plurality of loop antennas. Each loop antenna includes a plurality of parallel circuits each having a capacitor and a resistance element; and a plurality of looped conductors in a shape of a loop that is divided. The divided looped conductors are connected to each other via the parallel circuits, and the plurality of looped conductors and the plurality of parallel circuits form a loop.

A coil component includes coils in a multilayer body with a rectangular or substantially rectangular parallelepiped shape. The coil component includes outer electrodes, a first coil, and second coils. The first coil includes conductor patterns and via conductors. When the multilayer body is divided by a bisecting line into first and second regions in a longitudinal direction of the multilayer body when viewed in the stacking direction, the first coil is located in the first region. When viewed in the stacking direction, straight lines connecting the via conductors with a first outer electrode and a fourth outer electrode at a minimum distance cross an opening region of the first coil.

The invention provides a miniaturized radio frequency identification tag, which comprises a radio frequency identification chip and an antenna. The antenna comprises a plurality of loop antenna line segments. Each of loop antenna line segments is disposed on a corresponding insulating layer, and electrically connected to the radio frequency identification chip or the other loop antenna line segment via a corresponding conductive through hole. Accordingly, the structure of the antenna is fabricated by multi-layer loop antenna line segments so as to reduce the size of the radio frequency identification tag, effectively.

An RFID tag substrate includes an insulating substrate that has a mounting region in which a semiconductor device is disposed, the mounting region being included in a first surface of the insulating substrate, and a coil that is positioned at an outer edge portion of the insulating substrate. The coil includes a plurality of first coil conductors and a plurality of second coil conductors that are wound such that the first coil conductors and the second coil conductors each have the same number of turns and such that a direction in which the first coil conductors are wound and a direction in which the second coil conductors are wound are opposite to each other. The first coil conductors and the second coil conductors are alternately arranged in a thickness direction of the insulating substrate and connected in series to one another.

A resin molded body with an RFIC package incorporated therein is insert-molded incorporating therein a metal core material and an RFIC element connected to the metal core material. The RFIC element includes a ceramic multi-layer substrate that incorporates therein a coil conductor, and an RFIC chip mounted on a mounting surface of the multi-layer substrate. The RFIC chip is connected to the coil conductor by nano-particle bonding or ultrasonic bonding. The coil conductor is coupled with the core material in a magnetic field coupling scheme.

A compact wireless communication includes a first radiating element and a second radiating element, which define and function as a dipole antenna, a feeder circuit including a wireless IC chip coupled with the first and second radiating elements, and a feeder substrate that is provided with the wireless IC chip. The first radiating element is provided to the feeder substrate. The second radiating element is provided to a substrate other than the feeder substrate.

In some embodiments, an RFID device may include a multilayer reactive strap having a first substrate, a first conductor portion, a second conductor portion, and a first connection. The first conductor portion may enclose a first area and may be disposed on a first side of first substrate. A second conductor portion may enclose a second area and may be disposed on a second side of the first substrate. A first connection may couple the first conductor portion and the second conductor portion together, and may thereby form a multiturn coil that includes both the first conductor portion and the second conductor portion.

A noncontact communication medium includes an antenna coil that is formed on a substrate having a through-hole and induces power with application of a magnetic field from an outside, and a processing circuit that operates using the power induced by the antenna coil. The processing circuit is inserted in the middle of the antenna coil. The antenna coil is wound in a loop shape along an outer periphery of the substrate. An outer peripheral end of the antenna coil is connected to the through-hole. A portion of the antenna coil on the substrate facing a position of the through-hole has a shape recessed to an inner peripheral side of the antenna coil in a winding direction.

A radio IC device includes an electromagnetic coupling module includes a radio IC chip arranged to process transmitted and received signals and a feed circuit board including an inductance element. The feed circuit board includes an external electrode electromagnetically coupled to the feed circuit, and the external electrode is electrically connected to a shielding case or a wiring cable. The shielding case or the wiring cable functions as a radiation plate. The radio IC chip is operated by a signal received by the shielding case or the wiring, and the answer signal from the radio IC chip is radiated from the shielding case or the wiring cable to the outside. A metal component functions as the radiation plate, and the metal component may be a ground electrode disposed on the printed wiring board.

A dual IC card of the present invention includes: an IC module having a contact terminal portion contacting an external machine, a connecting coil configuring a contactless terminal portion by electromagnetic coupling, and an IC chip having a contact communication function and a contactless communication function; an antenna formed along a coil wiring path that defines an inductance and having a coupling coil portion electromagnetically coupling with the connecting coil of the IC module, a main coil portion formed along a coil wiring path that defines an inductance and connected to the coupling coil portion for performing contactless communication with the external machine, and a resistance-increasing portion provided in a section that forms the coil wiring path of at least one of the coupling coil portion and the main coil portion increase electrical resistance in the section; and a plate-like card body in which the antenna is arranged.