Abstract: A calibration circuit includes a selection unit, a power detector, an analog-to-digital converter and a calibrator. The selection unit is connected to the plurality of channels, selects two channels from among the plurality of channels, provides a test signal to the selected two channels, and receives a test result signal from the selected two channels. The power detector detects power of the selected two channels. The analog-to-digital converter performs an A/D conversion on an output of the power detector. The calibrator calibrates the phases and the gains between the plurality of channels based on an output of the analog-to-digital converter. One of the plurality of channels is set as a reference channel, phases and gains of remaining channels other than the reference channel among the plurality of channels are sequentially optimized based on the reference channel, and a phase and a gain of the reference channel is optimized.

Abstract: A variable gain phase shifter includes an I/Q generator and a vector summation circuit. The I/Q generator generates phase signals based on an input signal. The vector summation circuit adjusts magnitudes and directions of first, second, third and fourth in-phase vectors and first, second, third and fourth quadrature vectors, and generates an output signal by summing the in-phase vectors and the quadrature vectors, based on the phase signals, selection signals and current control signals. The vector summation circuit includes first, second, third and fourth vector summation cells and first, second, third and fourth current control circuits. The first and second vector summation cells adjust the directions of the first and second in-phase vectors and the first and second quadrature vectors. The third and fourth vector summation cells adjust the directions of the third and fourth in-phase vectors and the third and fourth quadrature vectors.

Abstract: A beam-forming circuit includes a multi mode power amplifier, a variable gain low noise amplifier, a variable gain phase shifter and a first switch circuit. The multi mode power amplifier amplifies a first RF intermediate signal generated based on a first RF input signal to generate a first RF output signal and performs a first transmission gain adjustment function based on a first control signal in a transmission mode. The variable gain low noise amplifier amplifies a second RF input signal to generate a second RF intermediate signal and performs a first reception gain adjustment function based on a second control signal in a reception mode.

Abstract: A variable gain phase shifter includes an I/Q generator and a vector summation circuit. The I/Q generator generates phase signals based on an input signal. The vector summation circuit adjusts magnitudes and directions of first, second, third and fourth in-phase vectors and first, second, third and fourth quadrature vectors, and generates an output signal by summing the in-phase vectors and the quadrature vectors, based on the phase signals, selection signals and current control signals. The vector summation circuit includes first, second, third and fourth vector summation cells and first, second, third and fourth current control circuits. The first and second vector summation cells adjust the directions of the first and second in-phase vectors and the first and second quadrature vectors. The third and fourth vector summation cells adjust the directions of the third and fourth in-phase vectors and the third and fourth quadrature vectors.

Abstract: A variable gain phase shifter includes an I/Q generator and a vector summation circuit. The I/Q generator generates phase signals based on an input signal. The vector summation circuit adjusts magnitudes and directions of first, second, third and fourth in-phase vectors and first, second, third and fourth quadrature vectors, and generates an output signal by summing the in-phase vectors and the quadrature vectors, based on the phase signals, selection signals and current control signals. The vector summation circuit includes first, second, third and fourth vector summation cells and first, second, third and fourth current control circuits. The first and second vector summation cells adjust the directions of the first and second in-phase vectors and the first and second quadrature vectors. The third and fourth vector summation cells adjust the directions of the third and fourth in-phase vectors and the third and fourth quadrature vectors.

Abstract: A variable gain phase shifter includes an I/Q generator and a vector summation circuit. The I/Q generator generates phase signals based on an input signal. The vector summation circuit adjusts magnitudes and directions of first, second, third and fourth in-phase vectors and first, second, third and fourth quadrature vectors, and generates an output signal by summing the in-phase vectors and the quadrature vectors, based on the phase signals, selection signals and current control signals. The vector summation circuit includes first, second, third and fourth vector summation cells and first, second, third and fourth current control circuits. The first and second vector summation cells adjust the directions of the first and second in-phase vectors and the first and second quadrature vectors. The third and fourth vector summation cells adjust the directions of the third and fourth in-phase vectors and the third and fourth quadrature vectors.

Abstract: A beam-forming circuit includes a multi mode power amplifier, a variable gain low noise amplifier, a variable gain phase shifter and a first switch circuit. The multi mode power amplifier amplifies a first RF intermediate signal generated based on a first RF input signal to generate a first RF output signal and performs a first transmission gain adjustment function based on a first control signal in a transmission mode. The variable gain low noise amplifier amplifies a second RF input signal to generate a second RF intermediate signal and performs a first reception gain adjustment function based on a second control signal in a reception mode.

Abstract: A wireless electric power transmitter for transmitting electric power for a charging function to a wireless electric power receiver is provided. The wireless electric power transmitter includes an electric power supply unit which supplies electric power; an amplifier which amplifies and outputs the electric power supplied from the electric power supply unit by a preset gain as a magnitude of measured impedance increases; and a transmitter which transmits the amplified electric power to the wireless electric power receiver.

Abstract: A power amplifier includes a common source amplifier and a common gate amplifier circuit. The common source amplifier circuit has a terminal connected to a radio frequency (RF) input terminal and uses a source terminal commonly as an input terminal and an output terminal of the power amplifier. The common gate amplifier circuit has a terminal connected to the common source amplifier circuit and another terminal connected to an RF output terminal, and uses a gate terminal commonly as the input terminal and the output terminal of the power amplifier. The common gate amplifier circuit includes a Doherty amplifier including a main power amplifier and an auxiliary power amplifier that is connected to the main power amplifier in parallel.

Abstract: A power amplifier according to examples includes an amplifying circuit configured to amplify an input signal, a feedback circuit configured to feedback the amplified signal to the amplifying unit, and a feedback controlling circuit configured to control a power of the fed-back signal based on a power of the input signal. The feedback controlling unit performs controlling so that the power of the fed-back signal is increased as the power of the input signal is increased.

Abstract: A power amplifier include an amplifier including at least one field effect transistor (FET) that operates in an amplifying stage configured to amplify an input signal, and a body controller configured to control a bias voltage of a body terminal of the FET based on a power of the input signal. The body controller performs controlling so that the bias voltage of the body terminal is reduced in response to the power of the input signal being increased. Accordingly, such a power amplifier exhibits improved linearity.

Abstract: A power amplifier includes a common source amplifier and a common gate amplifier circuit. The common source amplifier circuit has a terminal connected to a radio frequency (RF) input terminal and uses a source terminal commonly as an input terminal and an output terminal of the power amplifier. The common gate amplifier circuit has a terminal connected to the common source amplifier circuit and another terminal connected to an RF output terminal, and uses a gate terminal commonly as the input terminal and the output terminal of the power amplifier. The common gate amplifier circuit includes a Doherty amplifier including a main power amplifier and an auxiliary power amplifier that is connected to the main power amplifier in parallel.

Abstract: Provided is a power amplifier installed in wireless communication terminals and systems. According to one aspect of the present invention, a reconfigurable power amplifier capable of selecting a wide band frequency is provided. The reconfigurable power amplifier includes input transistors receiving a radio frequency (RF) signal and a reconfigurable adaptive power cell configured to select the wide band frequency by applying a common-gate bias voltage to a plurality of common-gate transistors with a plurality of separate common gates to amplify the RF signal.

Abstract: A power amplifier according to examples includes an amplifying circuit configured to amplify an input signal, a feedback circuit configured to feedback the amplified signal to the amplifying unit, and a feedback controlling circuit configured to control a power of the fed-back signal based on a power of the input signal. The feedback controlling unit performs controlling so that the power of the fed-back signal is increased as the power of the input signal is increased.

Abstract: A power amplifier include an amplifier including at least one field effect transistor (FET) that operates in an amplifying stage configured to amplify an input signal, and a body controller configured to control a bias voltage of a body terminal of the FET based on a power of the input signal. The body controller performs controlling so that the bias voltage of the body terminal is reduced in response to the power of the input signal being increased. Accordingly, such a power amplifier exhibits improved linearity.

Abstract: Provided is a power amplifier installed in wireless communication terminals and systems. According to one aspect of the present invention, a reconfigurable power amplifier capable of selecting a wide band frequency is provided. The reconfigurable power amplifier includes input transistors receiving a radio frequency (RF) signal and a reconfigurable adaptive power cell configured to select the wide band frequency by applying a common-gate bias voltage to a plurality of common-gate transistors with a plurality of separate common gates to amplify the RF signal.

Abstract: A bias circuit may include an envelope detecting unit detecting an envelope of an input signal, a source voltage generating unit generating a source voltage using a power supply voltage, and an envelope amplifying unit receiving the power supply voltage and the source voltage as a driving voltage and amplifying an envelope signal detected by the envelope detecting unit to generate a first bias voltage.

Abstract: A bias circuit may include an envelope detecting unit detecting an envelope of an input signal, a source voltage generating unit generating a source voltage using a power supply voltage, and an envelope amplifying unit receiving the power supply voltage and the source voltage as a driving voltage and amplifying an envelope signal detected by the envelope detecting unit to generate a first bias voltage.

Abstract: A transceiver using resonant coupling and nonlinear effect by plasma wave may include a split ring resonator transmitter and a split ring resonator receiver. The split ring resonator transmitter is formed by a split ring resonator antenna that transmits a clock signal. The split ring resonator receiver receives the clock signal by a resonant coupling, and the split ring resonator receiver is separated from the split ring resonator transmitter by a first distance.

Abstract: A power amplifier may include: an amplification unit amplifying a power level of an input signal, a negative feedback circuit unit connected between an input terminal and an output terminal of the amplification unit and a linearization circuit unit connected between the negative feedback circuit unit and the input terminal of the amplification unit to predistort and linearize a signal from the negative feedback circuit unit, and to provide the signal to the input terminal of the amplification unit.