Abstract: A wireless communication module includes a controller configured to control wireless communication operations, an antenna module that includes a first antenna device, and a matching circuit configured to perform impedance matching between the controller and the antenna module, wherein the first antenna device includes a heat dissipating sheet with a first pattern that transceives wireless signals by detecting a surrounding magnetic flux.

Abstract: A cover of a mobile device includes a metal structure disposed to cover one surface of the mobile device. The metal structure includes a metal material, and operates as an antenna for a wireless communication of the mobile device.

Abstract: A near-field communication (NFC) card reader may include a monitor configured to measure an amplitude of a magnetic field induced by an antenna; a gain controller configured to determine an amplification gain based on the measured amplitude of the magnetic field and output a gain control signal; a signal restoration unit configured to receive a carrier signal and a data signal that overlaps with the carrier signal via the antenna, and restore the data signal from the received signals; and a variable-gain amplifier configured to amplify the data signal restored by the signal restoration unit according to the gain control signal.

Abstract: A resonance frequency of a near field communication (NFC) antenna module may be set to be equal to a first frequency by a resonance unit included in the NFC antenna module. The NFC module may include a matching circuit connected to the NFC antenna module. The matching circuit may include terminals exposed to the outside such that the antenna module is detachable from the matching circuit.

Abstract: A cover of a mobile device includes a metal structure disposed to cover one surface of the mobile device. The metal structure includes a metal material, and operates as an antenna for a wireless communication of the mobile device.

Abstract: A wireless communication module includes a controller configured to control wireless communication operations, an antenna module that includes a first antenna device, and a matching circuit configured to perform impedance matching between the controller and the antenna module, wherein the first antenna device includes a heat dissipating sheet with a first pattern that transceives wireless signals by detecting a surrounding magnetic flux.

Abstract: A matching circuit of a near field communication (NFC) device includes a resonance unit connected between a first terminal and a second terminal of an antenna. The antenna is responsive to an electromagnetic wave. The resonance unit includes a first capacitor connected between the first terminal and the second terminal of the antenna. A matching unit is configured to perform impedance matching between the antenna and an NFC chip. The matching unit is connected between the first terminal and the second terminal of the antenna.

Abstract: The near field communication (NFC) circuit includes an NFC reader circuit configured to communicate with an outside through an antenna, a resonant and matching circuit connected between the NFC reader circuit and the antenna, an NFC card circuit connected to nodes and configured to communicate with the outside through the antenna, and a processor configured to output a plurality of control signals when the NFC reader circuit is enabled, wherein the NFC card circuit is configured to control a resonant frequency of the antenna in response to the plurality of control signals.

Abstract: A near-field communication (NFC) card reader may include a monitor configured to measure an amplitude of a magnetic field induced by an antenna; a gain controller configured to determine an amplification gain based on the measured amplitude of the magnetic field and output a gain control signal; a signal restoration unit configured to receive a carrier signal and a data signal that overlaps with the carrier signal via the antenna, and restore the data signal from the received signals; and a variable-gain amplifier configured to amplify the data signal restored by the signal restoration unit according to the gain control signal.

Abstract: A method of operating a contactless integrated circuit (IC) card reader includes calculating a first transition time of at least one first magnetic pulse during a first transition interval and calculating a second transition time of a second magnetic pulse during a second transition interval. The first transition time is calculated in a calibration phase, and the second transition time is calculated in a detection phase. A contactless IC card is determined to be within a communication rage of the reader based on a comparison of the first and second transition times.

Abstract: A radio frequency (RF) transmission circuit includes an antenna connection terminal, a plurality of amplifiers connected to the antenna connection terminal in parallel, a plurality of drivers for driving the plurality of amplifiers, and a control circuit configured to control operation of the plurality of drivers based on information indicating a characteristic of a RF signal to be transmitted through the antenna connection terminal.

Abstract: A resonance frequency of a near field communication (NFC) antenna module may be set to be equal to a first frequency by a resonance unit included in the NFC antenna module. The NFC module may include a matching circuit connected to the NFC antenna module. The matching circuit may include terminals exposed to the outside such that the antenna module is detachable from the matching circuit.

Abstract: A matching circuit of a near field communication (NFC) device includes a resonance unit connected between a first terminal and a second terminal of an antenna. The antenna is responsive to an electromagnetic wave. The resonance unit includes a first capacitor connected between the first terminal and the second terminal of the antenna. A matching unit is configured to perform impedance matching between the antenna and an NFC chip. The matching unit is connected between the first terminal and the second terminal of the antenna.

Abstract: A cover of a mobile device includes a metal structure disposed to cover one surface of the mobile device. The metal structure includes a metal material, and operates as an antenna for a wireless communication of the mobile device.

Abstract: A method of operating a contactless integrated circuit (IC) card reader includes calculating a first transition time of at least one first magnetic pulse during a first transition interval and calculating a second transition time of a second magnetic pulse during a second transition interval. The first transition time is calculated in a calibration phase, and the second transition time is calculated in a detection phase. A contactless IC card is determined to be within a communication rage of the reader based on a comparison of the first and second transition times.

Abstract: A radio frequency (RF) transmission circuit includes an antenna connection terminal, a plurality of amplifiers connected to the antenna connection terminal in parallel, a plurality of drivers for driving the plurality of amplifiers, and a control circuit configured to control operation of the plurality of drivers based on information indicating a characteristic of a RF signal to be transmitted through the antenna connection terminal.

Abstract: The near field communication (NFC) circuit includes an NFC reader circuit configured to communicate with an outside through an antenna, a resonant and matching circuit connected between the NFC reader circuit and the antenna, an NFC card circuit connected to nodes and configured to communicate with the outside through the antenna, and a processor configured to output a plurality of control signals when the NFC reader circuit is enabled, wherein the NFC card circuit is configured to control a resonant frequency of the antenna in response to the plurality of control signals.

Abstract: A patch antenna for receiving high frequency wireless signal and a rectenna using the same, more particularly, an impedance-matched patch antenna adopting a slot capacitive coupling structure and a rectenna capable of generating electrical energy from the wireless signals having different frequency band. A rectenna for receiving an A.C. wireless signal carrying electrical energy and converting the wireless signal into a D.C. electrical energy, is comprised of: a patch antenna for receiving the wireless signal comprising an dielectric substrate, a patch that is formed at the upper area of the surface of the dielectric substrate and providing the first frequency response characteristics, a ground plane formed on the other surface of the dielectric substrate, and an impedance matching means providing the second frequency response characteristics; and a rectifying unit that converts the wireless signal, received via the patch antenna, into a D.C. electrical energy by rectifying the wireless signal.

Abstract: An electricity charging module using a hysteresis switch includes a storage capacitor that preliminarily stores electrical energy supplied from an external power source, a charging unit for preventing over-charging or over-discharging through monitoring of the charging state of the rechargeable battery, and a hysteresis switch that has a larger turn-on voltage level than the turn-off voltage level, and located between the storage capacitor and the charging unit, thereby electrically connecting or disconnecting the storage capacitor with the charging unit.

Abstract: An electricity charging module using a hysteresis switch includes a storage capacitor that preliminarily stores electrical energy supplied from an external power source, a charging unit for preventing over-charging or over-discharging through monitoring of the charging state of the rechargeable battery, and a hysteresis switch that has a larger turn-on voltage level than the turn-off voltage level, and located between the storage capacitor and the charging unit, thereby electrically connecting or disconnecting the storage capacitor with the charging unit.