Abstract: A radio frequency (RF) weak magnetic field detection sensor includes a ferromagnetic core, a pickup coil disposed to surround the ferromagnetic core, a substrate that includes an opening, a core pad connected to the ferromagnetic core and a coil pad connected to the pickup coil, and an insulating tube interposed between the ferromagnetic core and the pickup coil. The insulating tube includes a bobbin around which the pickup coil is wound, and a core hole formed to pass through the bobbin and configured to accommodate the ferromagnetic core.

Abstract: A low-loss spiral coil includes a conducting wire wound N turns of which a width of each of wires corresponding to each of sections of the conducting wire is determined by setting an entire width of the conducting wire to be a width of M sections of the conducting wire, and then determining the width of each of the wires such that a resistance of the spiral coil formed based on the width of the M sections is minimized.

Abstract: An apparatus and method for transmitting and receiving magnetic field signals in a magnetic field communication system are provided. The apparatus includes a controller configured to generate a communication signal, matching units that are configured to receive the communication signal and that respectively correspond to different matching frequencies, and loop antennas that are connected to the matching units, respectively, and that are configured to convert communication signals according to the different matching frequencies into magnetic transmission signals in the form of magnetic field energy and to transmit the magnetic transmission signals.

Abstract: Disclosed is a resonator for expanding a transfer distance. A conical resonator includes a metal layer configured to operate according to a resonant frequency, and a dielectric layer coupled to the top or bottom of the metal layer to space the metal layer apart from another metal layer without overlap, wherein the metal layer and the dielectric layer have a Swiss-roll structure, and include an input face to which power is supplied on the bottom and an open face on the top.

Abstract: The atomic magnetometer includes a light source device configured to output a linearly polarized irradiation light and a circularly polarized pump light, a first vapor cell including an alkali metal atom, receiving the linearly polarized irradiation light, and outputting a first transmitted light, a second vapor cell including an alkali metal atom, receiving the linearly polarized irradiation light, and outputting a second transmitted light, a magnetic field application device configured to apply a bias magnetic field in opposite directions to the first vapor cell and the second vapor cell, and a measuring device configured to obtain the magnetic field signal based on a differentiation of a first polarization rotation signal corresponding to a polarization state of the first transmitted light and a second polarization rotation signal corresponding to a polarization state of the second transmitted light.

Abstract: Disclosed is a wireless power transmitting device and method, the wireless power transmitting device including, in response to detection of a power receiver within a predetermined separation distance from a charging pad, a controller configured to generate a magnetic field through a transmission coil with a multilayer structure in which a plurality of coil layers of different sizes are stacked, and a power transmitter configured to wirelessly transmit, to a reception coil of the power receiver, a power signal generated using magnetic fields generated by the plurality of coil layers.

Abstract: A receiver of a wireless power transmission system may include a capacitor-and-inductor configured to receive power from a transmitter using a resonance, at least one capacitor configured to connect to an output node of the receiver, and a plurality of switches configured to control current flow within the receiver. The plurality of switches may be controlled so that the capacitor-and-inductor may be disconnected from the at least one capacitor and the output node at preset periods. Current resonating in the capacitor-and-inductor may increase during disconnection between the at least one capacitor and the output node. The plurality of switches may output the increased current to the battery by connecting the capacitor-and-inductor to the capacitor and the output node after the period, connect at least one capacitor and the output node in series after the period, and operate to reduce root mean square (RMS) current within the receiver.

Abstract: Provided is a wireless power reception apparatus which receives a power from a wireless power transmission apparatus. A wireless power reception apparatus which receives a power from a wireless power transmission apparatus, the wireless power reception apparatus comprising a duty controller configured to control a duty cycle; a power converter configured to convert an effective load resistance according to the duty cycle; a reception resonator configured to receive a power from a transmission coil of the wireless power transmission apparatus, wherein the duty cycle and a current of the transmission coil is adjusted based on a load resistance of the wireless power reception apparatus.

Abstract: Provided is a wireless power reception apparatus for wirelessly receiving power from a wireless power transmission apparatus, the wireless power reception apparatus including a reception coil configured to receive power by a harmonic with an n*f0 frequency that is generated through electromagnetic induction with the wireless power transmission apparatus; a matching circuit configured to transfer the harmonic with the n*f0 frequency to a harmonic generator; the harmonic generator configured to generate at least one harmonic with an m*n*f0 frequency by applying a multiplication factor m to the transferred harmonic with the n*f0 frequency; a filter configured to filter the harmonic with the m*n*f0 frequency; and a harmonic transmission coil configured to transmit the filtered harmonic with the m*n*f0 frequency to the wireless power transmission apparatus, and to attenuate the harmonic with the n*f0 frequency that is generated from the wireless power transmission apparatus.

Abstract: A wireless power receiving apparatus, according to an example embodiment, may include a receiving coil in which a first wire including a copper core and a second wire not including a copper core are wound around a same axis. The second wire may be located at a pitch of the first wire, and a diameter of the second wire may correspond to the pitch of the first wire.

Abstract: Disclosed is a wireless power receiving apparatus capable of controlling an effective load resistance. The wireless power receiving apparatus may include a rectifier configured to generate a rectified voltage based on a magnetic field generated in a wireless power transmitting apparatus, and a controller configured to transmit, to the rectifier, a control signal for controlling a rectified phase of the rectifier to adjust an effective load resistance of the wireless power receiving apparatus.

Abstract: Provided is a wireless power transmission device to reduce an electromagnetic wave except for a signal to be transmitted during wireless power transmission, the wireless power transmission device including a transmitter configured to generate a magnetic field by inputting a high-frequency power signal generated by a transmission circuit into a first coil, a receiver configured to generate an induced current by allowing the generated magnetic field to pass through a second coil, and a reducer configured to reduce a harmonic component of the high-frequency power signal using a third coil inserted on a path between the transmitter and the receiver.

Abstract: Provided are a wireless power transmission device for transmitting power to a wireless power receiving device and the wireless power receiving device for receiving the power from the wireless power transmission device. The wireless power transmission device includes a first coil provided in a first direction; a second coil provided in a second direction that is perpendicular to the first direction, and connected to both ends of the first coil; and a voltage source configured to supply voltage to the first coil and the second coil. The first coil and the second coil may generate an electric field and a magnetic field in response to the voltage being supplied from the voltage source.

Abstract: Disclosed is a magnetic field shielding apparatus including an energy transmitter configured to generate a magnetic field, an energy receiver configured to receive the magnetic field generated by the energy transmitter, and a magnetic shield configured to shield a leaked magnetic field that is not received by the energy receiver, the magnetic shield including at least one closed region through which the leaked magnetic field passes, and at least one open region including a protrusion through which the leaked magnetic field moves to an inside of the magnetic field shielding apparatus after absorbed into the closed region.

Abstract: Provided is an apparatus for reducing an electromagnetic wave in a wireless power transmitter using a reducing coil, the apparatus that may cancel external emission of a magnetic field formed at a transmission coil using the reducing coil based on induced electromotive force.

Abstract: Disclosed is a wireless charging method and apparatus in a two-dimensional (2D) circular array structure that may form charging areas uniform in energy density. The wireless charging method includes receiving a current by a plurality of transmitting coils, and generating a three-dimensional (3D) wireless charging area that is available for wireless charging in a 3D space using a rotating magnetic field and a vertical magnetic field by the transmitting coils that are arranged in a circular form on a 2D plane.

Abstract: Disclosed is a wireless charging apparatus and method, the apparatus including a controller configured to control the wireless charging apparatus, and a transmitter configured to form a rotating magnetic field in a three-dimensional (3D) space in response to a first clock signal and a second clock signal generated under a control of the controller, wherein a phase difference between the first clock signal and the second clock signal is 90 degrees.

Abstract: Provided is a wireless charging apparatus for performing wireless charging of an electronic device including a receiving coil located in a three-dimensional (3D) wireless charging zone using a plurality of transmitting coils arranged in the 3D wireless charging zone and at least one power source configured to supply a current to the plurality of transmitting coils.

Abstract: A coaxial resonance coil having a toroidal shape for wireless power transmission is provided. The coaxial resonance coil may include a central conductive wire used as a power feeding loop for indirectly feeding power to a resonance coil, and an outer conductive wire used as a resonance coil which is wound a plurality of turns in a toroidal shape around the central conductive wire as an axis.

Abstract: A receiver of a wireless power transmission system may include a capacitor-and-inductor configured to receive power from a transmitter using a resonance, at least one capacitor configured to connect to an output node of the receiver, and a plurality of switches configured to control current flow within the receiver. The plurality of switches may be controlled so that the capacitor-and-inductor may be disconnected from the at least one capacitor and the output node at preset periods. Current resonating in the capacitor-and-inductor may increase during disconnection between the at least one capacitor and the output node. The plurality of switches may output the increased current to the battery by connecting the capacitor-and-inductor to the capacitor and the output node after the period, connect at least one capacitor and the output node in series after the period, and operate to reduce root mean square (RMS) current within the receiver.