Abstract:
An apparatus for optimizing a quality factor Q associated with an electrical resonator system includes an LC resonator and an optimizing circuit for providing a negative resistance. The optimizing circuit is electrically coupled to the resonator circuit, and includes two CMOS transistor pairs with the gates of the PMOS transistors cross-coupled with inputs to the resonator through capacitors, and the gates of the NMOS transistor cross-coupled with the inputs to the resonator through capacitors. The optimizing circuit receives at least one control voltage for varying the negative resistance by selectively biasing the PMOS transistors and NMOS transistors. The optimizing circuit also includes a current source for providing a controlled current to the CMOS transistor pairs. The current source is situated either between a supply voltage and the CMOS transistor pairs, or between the CMOS transistor pairs and a ground reference voltage. A current-control voltage controls the current flowing through the CMOS transistor pairs.
Abstract:
An effective means and apparatus for generating a negative resistance including a circuit element that exhibits an increase in current as the applied voltage is decreased. Other embodiments of the present invention provide electronic means for improving the quality Q factor of on-chip resonators, which enables the creation of high-performance bipolar RF circuits with a minimum of external components.
Abstract:
PURPOSE: A wireless power receiving device, a method for controlling wireless power receiving in the wireless power receiving device and a device thereof are provided to decrease waste of wireless power by not receiving the wireless power when the wireless power is not necessary, without resonance. CONSTITUTION: A wireless power receiving device includes a target resonator(210), a resonator switch(220) and a resonator controller(260). The target resonator includes a capacitor and an inductor, and receives electromagnetic energy from a source resonator. The resonator switch controls resonance of the target resonator by removing capacitance of the capacitor when it is turned on. The resonator controller controls turn-on of the resonator switch when a user requests blocking of wireless power or efficiency of receiving wireless power is lower than predetermined efficiency. [Reference numerals] (220) Resonator switch; (260) Resonator controller
Abstract:
A power supplying apparatus which supplies power from a power source supplying apparatus to a wireless power transmitting apparatus according to the embodiment of the present invention includes a converting unit which receives DC power from the power source supplying apparatus and converts the DC power into AC power. The power supplying apparatus transmits a power control signal for receiving the DC power determined according to a power transmission state variation between the wireless power transmitting apparatus and a wireless power receiving apparatus to the power source supplying apparatus. [Reference numerals] (230) Current sensing part; (240) Oscillator; (250) Converting unit; (260,520) Control unit; (270) Storage unit; (280) DC blocking unit; (290) Transmitting coil unit; (300) Wireless power reception device; (510) AC/DC converting unit; (520) Control unit; (530) DC blocking unit
Abstract:
PURPOSE: A wireless electromagnetic receiver and a wireless power transfer system are provided to increase efficiency of wireless power transfer by using a mechanical solid-state resonator having a high quality factor. CONSTITUTION: A first(210) device is a solid-state mechanical resonator being made of a magnetostrictive material. A second device is a converter converting mechanical energy generated based on oscillation of the mechanical resonator into electrical power. The mechanical resonator is operated by an external electromagnetic field at a resonance frequency of the resonator. The mechanical resonator is made of a magnetostrictive ferrite. The converter maintains a quality factor of the mechanical resonator.
Abstract:
PURPOSE: A wireless electromagnetic receiver and a wireless power transfer system are provided to locate an energy transducer near a resonator for maintaining a quality factor. CONSTITUTION: A wireless electromagnetic receiver comprises a first device(210) oscillating based on an electromagnetic field, and a second device transforming mechanical energy into electric power and being in contact with the first device. The first device is a solid-state mechanical resonator made of a magnetostrictive material. The second device is a transducer which transforms the mechanical energy generated based on the oscillation of the solid-state mechanical resonator into the electric power.
Abstract:
PURPOSE: A device and a method of compensating variable load characteristics are provided to automatically optimize the variable load characteristics according to frequency characteristics. CONSTITUTION: A variable load characteristics compensation device (1) includes a variable capacitor (30), an oscillation unit (40), a control signal generation unit (50), and a characteristics compensation unit (60). The variable capacitor includes a plurality of switching devices and comprises a plurality of capacitor devices in an array form. The oscillation unit generates an oscillation signal by using an inductor and the variable capacitor. The control signal generation unit generates an up-signal or a down-signal according to a compared result after comparing the received oscillation signal and a predetermined reference signal. The characteristics compensation unit controls the capacitance of the variable capacitor using the up-signal or the down-signal. [Reference numerals] (50) Control signal generation unit; (60) Characteristics compensation unit
Abstract:
PURPOSE: A low phase voltage control oscillator using a split ring resonator structure of a meta material is provided to improve phase noise characteristics through the improvement of a Q value using a unit cell of a SRR(Split Ring Resonator) structure. CONSTITUTION: A resonant portion includes a unit cell(210) of a SRR structure. A coupling capacitance value increases using the SRR structure having a property of a LHM(left handed material). The unit cell of the SRR structure comprises a first unit signal line(211), a second unit signal line(212), a third unit signal line(213), and a fourth unit signal line(214). The first unit signal line has an open slit portion(211a) formed on one end portion and an enclosed slit portion(211b) formed on the other one portion.
Abstract:
PURPOSE: A voltage controlled generator is provided to operate in a differential mode and a common mode by independently connecting a complementary active circuit element to both sides of a resonant unit. CONSTITUTION: A first oscillator comprises transistors(M5-M8) such as a complementary active element connected to both ends of a resonant unit(60) of a transformer base through an N-PMOS cross-connection structure. A second oscillator comprises transistors(M1-M4) such as a complementary active element connected to both ends of a resonant unit(60) of a transformer base through a gate coupling structure. A double band voltage controlled oscillator is formed by binding the first and second oscillators.
Abstract:
A transformer-based LC tank with differential-turned structure and the differential-tuned voltage controlled oscillator using the LC tank are provided to improve the quality factor of the resonant cavity by applying the transformer to the LC tank resonant cavity. A differential tuning voltage controlled oscillator comprises a current source portion(110), the first active portion(121), the second active portion(122), and the LC tank resonant cavity. The LC tank resonant cavity generates the resonant frequency and is located between the first active portion and the second active portion. The LC tank resonant cavity comprises the transformer and the first to fourth varactors(Cv11,Cv12,Cv21,Cv22). The first and second varactors are serially connected and the capacitance is controlled into the positive direction. The capacitance of the third and fourth varactors is controlled into the negative direction.