Abstract: A method and device for controlling a resonant inductor for implementing ZVS in a push-pull parallel resonant inverter is closed. The present disclosure provides A device comprising: a converter including a full-bridge circuit in which a first switch and a second switch form a first leg and a third switch and a fourth switch form a second leg and configured to convert a DC into an AC by turning on or off the switches; a resonant inductor circuit including a resonant inductor and a resonant switch connected in series and connected between two output nodes of the converter; a transmission coil connected in parallel with the resonant inductor circuit; and a controller configured to convert the DC into the AC by providing a switching timing for turning on or off the switches and control a switching timing of the resonant switch based on switching timings of the switches.

Abstract: An image processing-based foreign substance detection method in a wireless charging system and a device performing the method are disclosed. A method for detecting a foreign substance includes an operation of acquiring an image of a charging area of a wireless charging system, an operation of detecting, based on an RGB value of a frame of the image, a foreign substance in the charging area, an operation of discriminating a type of the foreign substance, and an operation of performing power control of the wireless charging system according to the type of the foreign substance.

Abstract: A system for performing magnetic field communication is disclosed. According to one embodiment of the present disclosure, a system for performing magnetic field communication may include a first current mode power supply having a voltage and one or more inductors connected thereto; a power amplifier connected to the first current mode power supply; a first matching impedance unit including a first capacitor connected to the power amplifier; and a first magnetic field antenna including a coil and a resistor connected in parallel with the first matching impedance unit.

Abstract: Provided is a robot charging apparatus to wirelessly charge a robot capable of walking, which includes a plurality of receiving coils fixed to legs of a robot and a transmitting coil moved and provided according to a position of the robot and wirelessly charges the robot in such a manner that the transmitting coil is provided between the plurality of receiving coils and coupled to the receiving coils by a magnetic field output from the transmitting coil.

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 operation method of a first communication node may comprise: receiving one or more polarized radio signals transmitted from a second communication node included in the communication system through one or more receive polarized antennas included in the first communication node; performing a receive polarized antenna alignment state adjustment operation so that a detection result for a magnitude of an electric field excited by the one or more polarized radio signals is maximized; and receiving a first polarized signal transmitted from the second communication node through at least part of the one or more receive polarized antennas based on a result of the receive polarized antenna alignment state adjustment operation.

Abstract: The present disclosure relates to a method and apparatus for performing multiple wireless charging. A method or performing wireless charging according to an embodiment of the present disclosure may comprise: identifying one or more receiving coils subject to wireless charging; setting a plurality of transmission frequencies based on a plurality of receiving coils being identified; and transmitting a wireless power transmission signal to the plurality of receiving coils using a plurality of transmitting coils connected to one inverter. Herein, a wireless power transmission signal transmitted from each transmitting coil belonging to the plurality of transmitting coils may be generated by applying the plurality of transmission frequencies in a pre-configured order.

Abstract: A wireless power transmission resonator using a conducting wire with a vertical rectangular cross-section is disclosed. The wireless power transmission resonator may include a first element including a first element upper part arranged in an upper end of a resonator and a first element lower part arranged in a lower end of the resonator, wherein the first element upper part and the first element lower part each may include a spiral layer having a spiral structure that is wound to face a wide surface of a conducting wire including a vertical rectangular cross-section and a second element arranged in a center of the resonator and between the first element upper part and the first element lower part and including a spiral layer having a spiral structure that is wound to face the wide surface of the conducting wire including the vertical rectangular cross-section.

Abstract: A wireless charging system for attenuating electromagnetic waves is provided. The wireless charging system includes a transmitter including a clock generator configured to generate clock signals having reverse phases from each other, inverters configured to output inverter voltage/current signals having a same magnitude and reverse phases from each other using the clock signals generated by the clock generator, matching portions respectively connected to the inverters and configured to output transmission coil voltage/current signals having a same magnitude and reverse phases from each other using the inverter voltage/current signals, and transmission coils respectively connected to the matching portions and configured to generate magnetic fields towards a reception coil using the transmission coil voltage/current signals.

Abstract: A wireless power transmitter that changes an operation frequency and an operation method of the same are provided. The operation method includes controlling the wireless power transmitter to operate at a first operation frequency included in an operation frequency set, changing an operation frequency of the wireless power transmitter from the first operation frequency to a second operation frequency that is different from an operation frequency of a second wireless power transmitter that is adjacent to the wireless power transmitter for every channel duration, and controlling the wireless power transmitter to operate at the second operation frequency.

Abstract: The present invention relates to a method and apparatus for performing position estimation of multiple receiving coil and wireless power transmission. A method for performing wireless power transmission according to an embodiment of the present disclosure may comprise: calculating a current value flowing through one or more transmitting (Tx) coils by measuring an impedance value of the one or more Tx coils; identifying whether a receiving (Rx) coil associated with the one or more Tx coils exists; when one or more Rx coils exist, calculating a correlation value between a Tx coil and a Rx coil for each of the one or more Rx coils; determining a position of the one or more Rx coils; and performing wireless power transmission to the one or more Rx coils.

Abstract: A method for calculating an altitude of a target through an apparatus for calculating an altitude of the target, which comprises a plurality of MIMO radar virtual antennas, may comprise: receiving electromagnetic waves reflected from the target through a pair of virtual antennas classified into an upper antenna and a lower antenna and alternately arranged in two columns linearly; obtaining range information and phase information of the target from the pair of virtual antennas by analyzing the electromagnetic waves; and calculating altitude information of the target from position information of the pair of virtual antennas, and the range information and the phase information.

Abstract: An atomic magnetometer with an extended measurement bandwidth is disclosed. The atomic magnetometer includes coils configured to transmit incident pump light and a bias magnetic field and a vapor cell positioned between the coils and receiving the pump light and the bias magnetic field transmitted from the coils and irradiation light incident from a direction perpendicular to the coils, wherein the vapor cell includes both a first alkali metal atom and a second alkali metal atom, which are isotopes of one of alkali metals.

Abstract: The present disclosure relates to an image processing method for a multi-dimensional region of interest (ROI) in a wireless charging system. More specifically, the method includes determining whether a surveillance target exists in the multi-dimensional ROI by performing, regarding the surveillance target, the process of removing a false-alarm region and including an excluded ROI.

Abstract: A wireless charging system, a method of removing a foreign object in the wireless charging system, and a computing device performing the method are provided. The wireless charging system includes a transmission coil cover mounted to surround a transmission coil of a transmission device, a reception coil cover mounted to surround a reception coil of a reception device, and a direct current (DC) conducting wire attached to each of the transmission coil cover and the reception coil cover, wherein the wireless charging system may be configured to remove a foreign object attached to the transmission coil cover or the reception coil cover by using a force acting on the DC conducting wire according to a direction of a current flowing in the DC conducting wire and a direction of a magnetic field perpendicular to the direction of the current.

Abstract: Exemplary embodiments provide a radar apparatus having a plurality of antenna elements and enabling to reduce a number of ADCs as long as being allowable according to a bandwidth of the ADC, reduce a chip area occupied by the ADC and interconnections in an integrated circuit, and prevent a synchronization problem between the ADCs by sampling receive signals of multiple channels at once. Frequencies of local oscillation signals used for downconverting receive signals are set to be different from each other by an amount of an offset frequency, so that each of band-limited receive signals obtained through respective RF paths may occupy a different position on a frequency axis of a frequency domain. Downconverted receive signals are combined into a single signal and converted into a single digital signal stream, and a signal processing of the digital signal stream in a digital domain enables to obtain target data.

Abstract: A resonant coil coupled with an electromagnetic field is disclosed. A Fraunhofer resonant coil includes an upper spiral element and a lower spiral element, an upper conical element connected to the upper spiral element and including one or more layers formed of a plurality of plies, a lower conical element connected to the lower spiral element and including one or more layers formed of a plurality of plies, and a feeding device connected to a gap between the upper conical element and the lower conical element and configured to supply power.

Abstract: Provided is a resonant multi-loop antenna circuit for magnetic field communication. The resonant multi-loop antenna circuit includes a first loop antenna and a second loop antenna arranged substantially on a same plane, and a first/a second matching circuit connected in series to the first and the second loop antenna respectively. The first matching circuit may be configured to minimize reactance of the first loop antenna and the first matching circuit connected in series to each other at a first carrier frequency, the second matching circuit may be configured to minimize the reactance of the second loop antenna and the second matching circuit connected in series to each other at a second carrier frequency, and the first loop antenna and the second loop antenna may be arranged so that a center of the first loop antenna is spaced apart from a center of the second loop antenna by a predetermined distance.

Abstract: Provided is a reflector/scatterer arranged around a side lobe beam which is generated from a transmission antenna, in a radiation direction of the side lobe beam, for use in expanding a communication service coverage area.

Abstract: An exemplary embodiment provides a signal receiver device capable of detecting a radio communication signal with a high signal-to-noise ratio while internally canceling an environmental noise. A signal receiver device according to an exemplary embodiment includes a first signal detection element; and a second signal detection element electrically connected to the first signal detection element and provided with a blocking member for attenuating a communication signal among received RF signals. The signal receiver device is configured to output a difference between a first detection signal detected by the first signal detection element and a second detection signal detected by the second signal detection element as a detected receive signal.