摘要:
An apparatus and method for matching impedance of an antenna by using Standing Wave Ratio (SWR) information is provided. While the impedance of the impedance matching unit is controlled, a region of a Smith chart in which initial total impedance of the impedance matching unit and the antenna is located by using an SWR calculated by an SWR operation unit, and the impedance of the impedance matching unit is controlled according to the determined region, thus correctly matching the impedance of the antenna.
摘要:
A method and apparatus for data communication in wireless power transmission are provided. A wireless power transmitter includes a resonance antenna configured to wirelessly transmit a power to a wireless power receiver, and receive a signal from the wireless power receiver, the signal including a sub-carrier. The wireless power transmitter further includes a controller configured to receive the signal from the resonance antenna, and receive data from the wireless power receiver based on the sub-carrier.
摘要:
In an apparatus for recognizing a security code having an electromagnetic band gap (EBG) pattern which uses reflection and transmission characteristics of the EBG pattern, a voltage controlled oscillator generates a signal to a power divider, which divides the power of the signal into halves, and outputs a first signal through a waveguide to be incident on the EBG pattern. The waveguide receives a signal reflected from the EBG pattern and outputs the reflected signal to a phase detector. A circulator outputs the second signal to the phase detector, which detects the phase difference between the reflected signal and the second signal, and outputs phase difference data to a data control unit, which determines whether the security code having the EBG pattern is recognized using the phase difference data. In an alternate embodiment, the voltage control oscillator is controlled to sequentially generate signals using power difference data.
摘要:
An electromagnetic bandgap (EBG) pattern structure includes a nonconductive substrate and a pattern assembly formed on the substrate. The EBG pattern structure also includes regularly arranged closed-loop patterns and open-loop patterns, both of which are made of a conductive material. The EBG pattern structure can be used to manufacture new security products by applying its frequency characteristics to securities or IDs and variously used in security technologies for preventing forgery and alteration because various security codes can be created by adjusting the variables of its EBG pattern.
摘要:
In an apparatus for recognizing a security code having an electromagnetic band gap (EBG) pattern which uses reflection and transmission characteristics of the EBG pattern, a voltage controlled oscillator generates a signal to a power divider, which divides the power of the signal into halves, and outputs a first signal through a waveguide to be incident on the EBG pattern. The waveguide receives a signal reflected from the EBG pattern and outputs the reflected signal to a phase detector. A circulator outputs the second signal to the phase detector, which detects the phase difference between the reflected signal and the second signal, and outputs phase difference data to a data control unit, which determines whether the security code having the EBG pattern is recognized using the phase difference data. In an alternate embodiment, the voltage control oscillator is controlled to sequentially generate signals using power difference data.
摘要:
Disclosed herein is the structure of a Square Quadrifilar Helical antenna (S-QHA). The structure of the S-QHA includes a square column, four radiation elements, and a feed network. The four radiation elements are formed on the square column. The feed network is disposed at the top or bottom of the square column, and feeds signals to the radiation elements at a phase difference of 90 degrees in a clockwise or counterclockwise direction. As a result, the S-QHA according to the present invention can receive circularly polarized signals.
摘要:
In a multi-band U-slot planar antenna, a limited ground plane is provided. A connector includes a ground terminal connected to the ground plane and a feeding terminal for feeding a signal. A planar radiation device includes a feeding point connected to the feeding terminal, a central U-slot having a symmetrical configuration about a central axis thereof, the central axis extending vertically from the feeding point, and at least one pair of auxiliary U-slots symmetrical with each other about the central axis. In the multi-band U-slot planar antenna, alternatively, at least one auxiliary U-slot may have a symmetrical configuration about the central axis.
摘要:
In a multi-band U-slot planar antenna, a limited ground plane is provided. A connector includes a ground terminal connected to the ground plane and a feeding terminal for feeding a signal. A planar radiation device includes a feeding point connected to the feeding terminal, a central U-slot having a symmetrical configuration about a central axis thereof, the central axis extending vertically from the feeding point, and at least one pair of auxiliary U-slots symmetrical with each other about the central axis. In the multi-band U-slot planar antenna, alternatively, at least one auxiliary U-slot may have a symmetrical configuration about the central axis.