Lg Electronics Inc.

Hong Teuk Kim

Kwy Ro Lee

Byungdu Oh

Young-Hwan Choi

Seung-Hyun Moon

Sergey E Sergeyev

Alexander N Belonozhkin

Hee Sub Lee

Jae Hyoung Park

Young Joon Ko

Young Woo Kwon

Sergey Khvorov

Dong Gu Im

Jae Yup Lee

Yong Kweon Kim

A radio frequency (RF) signal transmission/reception apparatus and an RF signal transmission/reception method are disclosed. The RF signal transmission/reception apparatus is adapted to perform a transmission/reception duplex function using a bi-directional mixer at the IF band or baseband, not at the RF band. When a reception signal of the RF band is passed through the bi-directional mixer, it is converted into a signal in any one of the IF band and the baseband. Also, when a transmission signal in any one of the IF band and the baseband is passed through the bi-directional mixer, it is converted into a signal of the RF band.

Radio frequency signal transmission/reception apparatus and radio frequency signal transmission/reception method

The present disclosure relates to a tuner capable of receiving a television broadcasting signal of a wide band having an operating frequency bandwidth of 48 MHz&#x2dc;1 GHz, wherein the tuner filters a radio frequency (RF) signal outputted from the low noise amplifier using a tunable filter. The tunable filter includes according to an embodiment an inductor and a variable capacitor as passive elements to reject harmonics. The tuner includes a mixer which mixes an output signal of the tunable filter with a local oscillator signal and converts the mixed signal to an In-phase and Quadrature IF signal, where the converted IF signal of I channel and Q channel is processed through an IF signal processor and is converted to an appropriate signal by a demodulator.

Tuner

An impedance control apparatus and method for portable mobile communication terminal is disclosed capable of accurately adjusting impedances relative to environment when the portable mobile communication terminal is being used, wherein an impedance of a first variable impedance matching part is varied to receive a reception impedance correction signal transmitted by a base station and to detect a reception strength, an impedance of the first variable impedance matching part is set by a impedance value of the largest reception strength out of the reception strengths, the portable mobile communication terminal varies the impedance of a second variable impedance matching part to transmit a transmission impedance correction signal to a base station and to allow the base station to detect the reception strength, and the impedance setting of the second variable impedance matching part is performed using the reception strength detected by the base station.

Impedance control apparatus and method for portable mobile communication terminal

An internal antenna of a wireless communication terminal, in which internal style folded monopole antenna is installed, is provided. The internal antenna of a wireless communication terminal includes a folded monopole antenna. The folded monopole antenna includes two folded radiation planes having a quarter wavelength, and reactances loaded to predetermined positions of the two radiation planes. Therefore, a space for installing the antenna in the terminal is minimized, and due to the no directional characteristics, the internal antenna can be applied to a wireless communication system of dual bandwidths.

Internal antenna of wireless communication terminal

A power amplifier for enhancing output efficiency. The power amplifier includes a first amplifier connected to a first power, a second amplifier connected to a second power, a common input impedance matching unit impedance matching inputted signals and outputting the inputted signals to the first amplifier and the second amplifier, a common output impedance matching unit impedance matching and outputting the signals amplified from the first amplifier and the second amplifier, an output impedance matching unit electrically connected between the first amplifier and the common output impedance matching unit, and modifying an output voltage value of the first amplifier to an output voltage value of the second amplifier, and an input impedance matching unit electrically connected between the common input impedance matching unit and the first amplifier, and compensating a phase shift occurring during the voltage modification of the output impedance matching unit.

Power amplifier

A microwave tunable filter having some advantages as follows: a) the integration of MEMS tunable filter and MMIC; b) the very low signal transmission loss and low dispersion; and c) the drastic variation and linear characteristic of frequency by means of MEMS capacitor and an external control signal. The microwave tunable MEMS filter includes a plurality of unit resonant cells, each unit resonant cell being formed by various serial and parallel combination of an inductor, a capacitor, a transmission line, and a variable MEMS capacitor, whereby capacitance variation of the variable MEMS capacitor in the unit resonant cell converts a resonant frequency of the unit resonant cell to thereby convert a center frequency of the filter.

Microwave tunable filter using microelectromechanical (MEMS) system

A magnetometer using a plurality of superconducting quantum interference devices (SQUIDs) includes a detecting part composed of a plurality of SQUIDs each detecting external magnetic flux, converting the detected external flux into a voltage value, and outputting a differential voltage of the converted voltage value, a signal-processing part for modulating, amplifying, and demodulating the differential voltage outputted by the detecting part, and a feedbacking part for converting a signal outputted by the signal-processing part into magnetic flux to feedback the signal to the loop of the SQUIDs.

Magnetometer using two squids

A high frequency signal generator using a superconducting quantum interference device is disclosed including: a magnetic signal generator for supplying a low frequency magnetic signal to a superconducting quantum interference device; a first filter for selectively supplying only the magnetic signal to the superconducting quantum interference device, and preventing a high frequency signal generated from the superconducting quantum interference device from flowing to the magnetic signal generator; the superconducting quantum interference device for frequency-multiplying the magnetic signal generated from the first filter to the high frequency signal of a sinusoidal wave according to the frequency, waveform and amplitude of the magnetic signal; a second filter for preventing the magnetic signal generated from the magnetic signal generator from flowing to a high frequency guide and antenna, and selectively supplying only the high frequency signal generated from the superconducting quantum interference device to the high frequency guide and antenna; and the high frequency guide and antenna for transmitting the high frequency signal supplied through the second filter to the exterior.

High frequency signal generator using superconducting quantum

Microwave harmonic mixer circuit of SQUID(Superconducting Quantum Interference Device) is disclosed, in which a magnetic flux to voltage conversion characteristics of SQUID is used for generating a higher harmonics from an LO(Local Oscillator) signal, and mixing the higher LO harmonics with a radio frequency(RF) signal, including an SQUID for adding a RF(Radio Frequency) signal to a magnetic flux of an LO(Local Oscillator) signal frequency for having a mixing of the frequencies done; a current applying part and a grounding part disposed on both sides of the SQUID and connected to a current source on one side and grounded on the other side respectively for supplying operation current to the SQUID; RF antenna parts one each disposed between the SQUID and the current applying part and the SQUID and the grounding part for feeding a RF signal into the SQUID; an LO signal source and antenna part for applying a flux of an LO signal frequency to the SQUID; and, an IF signal detecting part for detecting an IF(Intermediate Frequency) signal mixed in the SQUID, whereby a flux to voltage conversion characteristics of the SQUID of a superconducting junction is used in modulating the frequency and magnetic flux intensity of the LO signal for generating a dominant LO higher harmonics of very high order and mixing the higher harmonics with a high frequency RF signal in frequency base.

Growing community of inventors

Seoul, South Korea

Hong Teuk Kim