Samsung Electronics Co., Ltd.

Heung-bae Lee

Sang-yoon Jeon

Yun-seong Eo

Hee-Mun Bang

Sung-jae Jung

Seong-soo Lee

Ick-jin Kwon

Jin-Soo Park

Kwang-du Lee

Young-Eil Kim

Chang-Sik Yoo

Bum-Man Kim

Jin-soo Park

Hyung-sun Lim

Do-Hyung Kim

Dong-Hyun Lee

Joon-Hee Lee

Woo-shik Kang

Yong-Hun Kim

Kwy-ro Lee

Chun-deok Suh

Jin-wook Burm

Jinup Lim

Dae-ki Kim

Joongho Choi

Kyu-don Choi

Chong-ouk Kim

Il-ku Nam

Chang-joon Park

Si-gyoung Koo

Je-hyung Yoon

Chan-young Jeong

Seong-sik Song

Andrew Han

A radio frequency (RF) receiver and a method of receiving an RF signal are provided. The RF receiver includes a low-noise amplifying unit which amplifies a received signal while restricting out-of-band interference of the received signal, a sampling unit which performs sampling to convert the amplified signal to a discrete time domain signal, a frequency translation unit which down-converts the discrete time domain signal into a frequency band that enables the discrete time domain signal to be converted into a digital signal and restricts interference from a frequency within an aliasing band according to a sampling frequency, an anti-aliasing filtering unit which prevents aliasing from the down-converted signal, a clock unit which provides the sampling unit, the frequency translation unit, and the anti-aliasing filtering unit with sampling frequencies, and an analog-digital-converter which converts the converted signal into the digital signal.

RF receiver and method to receive, amplify, sample, down convert, anti-aliasing filter, and ADC convert an RF signal

A transmitter and a signal amplifier are provided. The signal amplifier includes a digital-to-analog converter converting an input digital signal into an analog signal, a local oscillator signal generator outputting in-phase and quadrature-phase oscillator signals, a first mixer mixing the analog signal with the in-phase local oscillator signal to output an in-phase high frequency signal, a second mixer mixing the analog signal with the quadrature-phase local oscillator signal to output a quadrature-phase high frequency signal, a main amplifier amplifying the in-phase high frequency signal output from the first mixer, and an auxiliary amplifier amplifying the quadrature-phase high frequency signal output from the second mixer.

Doherty amplifier and transmitter using mixer

An inductor circuit includes a pair of inductors connected in parallel with each other and a switch for turning on and off electric power to one of the pair of inductors. The inductance of the inductor circuit can be varied and the quality factor Q can be improved. Further, RF circuits employing the inductor circuit can generate an intended operating frequency.

Parallel-structured switched variable inductor circuit

A variable inductor is provided, which includes a first lead having both ends to receive a pair of difference signals, a second lead having both ends to receive a pair of the difference signals, and a switch selectively supplying a pair of the difference signals to the second lead by turning on/off according to a control signal. Accordingly, a variable inductor can be implemented that is compact and maximizes the variation rate of inductance.

Variable inductor

An N&#xd7;N multiple-input multiple-output (MIMO) transceiver is provided. The transceiver includes a plurality of transceivers, each including at least one transceiver circuit; an oscillation unit which is configured to generate a differential signal which is supplied to the at least one transceiver circuit; a plurality of buffers, which are mounted in a bypass line between the at least one transceiver circuit and the oscillation unit and are configured to amplify and bypass the differential signal or input and amplify the differential signal; and a buffer control unit which is configured to control the plurality of buffers to bypass or input the differential signal.

NxN multiple-input multiple-output transceiver

A mobile radio frequency identification (mRFID) reader having a receiving circuit is provided. The receiving circuit includes a local oscillator which generates a carrier signal at a predetermined frequency band; a mixer which mixes a tag signal received from a tag with the carrier signal, to lower a frequency of the tag signal; a phase adjusting block which adjusts a phase of the carrier signal by determining a phase of the tag signal; and a control block which processes the tag signal through a series of operations, and controls an operation of the phase adjusting block to compensate for a phase delay of the tag signal according to an output of the processed tag signal. Because the mRFID reader can be provided as small as a half size of a related art reader, a mobile communication terminal accommodating the mRFID reader can be compact-sized. Additionally, because the number of components for the receiving circuit decreases, not only the power consumption but also the unit price can be reduced.

Mobile radio frequency identification (mRFID) reader

A low noise amplifier is provided. The low noise amplifier includes: a low noise amplifying unit amplifying an input signal; a harmonic and noise generating unit disposed in an input terminal of the low noise amplifying unit, for generating a compensating signal for compensating for an intermodulation distortion signal and a thermal noise signal of the input signal to the low noise amplifying unit; and a load unit outputting the amplified input signal generated by the low noise amplifying unit.

Low noise amplifier

Provided is a mixer including: an amplifier amplifying an input signal using at least one amplifier element; a mixing unit mixing the input signal amplified by the amplifier with a local oscillator signal output from a local oscillator. The mixing unit includes at least one pair of switching elements switching the amplifier, and the switching elements are MOSFETs having gates and body nodes to which a same local oscillator signal is applied. Thus, a time required for turning on the switching elements can be reduced, and 1/f noise is also reduced. Also, an overdrive voltage can be increased with respect to local oscillator signals having an identical intensity. Thus, a relatively low voltage operation can be performed.

Mixer

A subharmonic mixer, including an amplification unit for amplifying an input signal using at least one pair of amplification devices connected in parallel and a mixing unit for mixing the amplified signal with local oscillation signals from local oscillators is provided. The mixing unit performs switching over the amplification devices and at least four pairs of switching devices connected in parallel with each other, two pairs of switching devices being connected in parallel with each other and performing switching over one amplification device. The switching devices are supplied with local oscillation signals having different phases respectively, and two switching devices forming a pair are connected in parallel with each other and supplied with local oscillation signals having a 180&#xb0; phase difference therebetween. Accordingly, the switching stage is formed with one stage, the operation is enabled with low-voltage power supplies, and noise performance, linearity, and gain are enhanced.

Subharmonic mixer capable of reducing noise and enhancing gain and linearlty

An integrated circuit having integrated inductors includes at least one pair of transistors, and at least one inductor group which includes a pair of inductors coupled to the at least one pair of the transistor, respectively. The pair of the inductors form a spiral shape on a plane and the inductors arranged symmetrically to each other. Magnetic fluxes, which are generated by current flows along the inductors of the at least one inductor group, are formed in a direction to mutually intensify the magnetic fluxes according to differential signals applied to the at least one transistors from outside. Accordingly, high inductance and high quality factor can be attained owing to the positive magnetic coupling of the inductors.

Integrated circuit having integrated inductors

Disclosed is a dual-band voltage-controlled oscillator using bias switching and output-buffer multiplexing. The dual-band voltage-controlled oscillator includes a power supply unit for supplying a source voltage; plural voltage-controlled oscillation units for outputting different oscillation frequencies according to controls of a certain tuning voltage; plural bias units for generating driving voltages for driving the voltage-controlled oscillation units and supplying the driving voltages to the voltage-controlled oscillation units; and plural buffers for selectively outputting oscillation frequencies of the plural voltage-controlled oscillation units. The present invention implements the dual-band voltage-controlled oscillator through bias switching and output-buffer multiplexing, which brings an advantage of elimination of interference between output frequencies to enhance phase noise characteristics.

Dual-band voltage-controlled oscillator using bias switching and output-buffer multiplexing

A quadrature voltage controlled oscillator having low phase noise and excellent output swing characteristics includes a first voltage controlled oscillator for outputting a positive in-phase output signal and a negative in-phase output signal; a second voltage controlled oscillator for outputting a positive quadrature-phase output signal and a negative quadrature-phase output signal, the second voltage controlled oscillator having a symmetrical structure with the first voltage controlled oscillator and constituting a feedback loop together with the first voltage controlled oscillator; a first constant current source for supplying constant current to the first voltage controlled oscillator in response to the output signals; and a second constant current source for supplying constant current to the second voltage controlled oscillator in response to the output signals.

Quadrature voltage controlled oscillator

A buffer amplifier, which includes a first differential signal amplifier including first and second NMOSFETs (N-type metal-oxide semiconductor field-effect transistors) amplifying differential input signals; a second differential signal amplifier including first and second PMOSFETs (P-type metal-oxide semiconductor field-effect transistors) amplifying the differential input signals; a first feedback resistor including an end commonly connected to drains of the first NMOSFET and the first PMOSFET and the other end commonly connected to gates of the first NMOSFET and the first PMOSFET; a second feedback resistor including an end commonly connected to drains of the second NMOSFET and the second PMOSFET and the other end commonly connected to gates of the second NMOSFET and the second PMOSFET; and a current source providing a bias current for driving the first and second differential signal amplifiers, is provided.

Buffer amplifier

A sigma-delta modulation method with low complexity is provided. To this end, in the present invention, an input signal is forwarded and an output signal is fed back to thus reduce the range of the noise transfer function of the sigma-delta modulator and to lower the frequency offset and the phase noise at low frequencies. A sigma-delta modulator for a frequency synthesizer may include one or more modulation units which are connected in series and perform a sigma-delta modulation to an input signal and a provided accumulated signal using a signal which is weighted with a feedback coefficient; and an output adder which adds an output signal from a terminal section of the modulation units and the input signal, and outputs the added signal for feedback to the modulation units.

Growing community of inventors

Suwon-si, South Korea

Heung-bae Lee