A circuit module includes a power amplifier, a switch, and a bypass capacitor. The power amplifier has a signal input node coupled to an input signal, a signal output node to generate an output signal, and a power input node coupled to a supply output signal of a supply modulator. The switch is coupled between the power input node of the power amplifier and the bypass capacitor. The bypass capacitor is an equivalently removable bypass capacitor coupled between the switch and a ground level.

Power amplifier module with power supply control. A power amplification control system can include an interface configured to receive a transceiver control signal from a transceiver. The power amplification control system can include a power amplifier control component configured to generate a power amplifier control signal based on the transceiver control signal from the transceiver and a power supply control component configured to generate a power supply control signal based on the transceiver control signal from the transceiver and to generate the power supply control signal based on a local control signal from the power amplifier control component.

Diversity receiver front end system with methods for improving signal processing using tunable matching circuits. The methods can include tuning impedance matching circuits based on frequency bands. For a first path, an impedance can be provided that reduces an in-band noise figure, increases an in-band gain, decreases an out-of-band noise figure, and/or decreases an out-of-band gain. In this way, signals propagated along selectively activated paths between an input of a receiving system and an output of the receiving system can be improved. The signals can be amplified using amplifiers disposed on corresponding paths between the input and output of the receiving system.

A power amplifier can include a carrier amplifier having first and second differential amplification cells with outputs coupled by a primary loop of a carrier transformer, and a peaking amplifier having first and second differential amplification cells with outputs coupled by a primary loop of a peaking transformer. The power amplifier can further include a combiner having a quarter-wave circuit implemented between the secondary loop of the carrier transformer and a secondary loop of the peaking transformer. The quarter-wave circuit can be configured to provide a characteristic impedance, such that the carrier and peaking amplifiers are presented with an impedance that is approximately the same as the characteristic impedance when both of the carrier and peaking amplifiers are turned on, and the carrier amplifier is presented with an impedance that is approximately twice the characteristic impedance when the carrier amplifier is turned on and the peaking amplifier is turned off.

Described herein are systems and methods that manage polarization in coherent optical receivers by using analog signal processing that eliminates the need for ultra-fast, power-hungry ADCs and DSPs and that would require digitization of the full-bandwidth signal path and result in bulky and expensive circuit designs. Various embodiments of the invention provide polarization correction by using an analog polarization correction circuit that implements the equivalent of two matrix operations. This is accomplished by using analog electronics that comprises a combination of variable and unity gain amplifiers to align polarizations of input signals to generate a polarization-corrected output signal that is further aligned with the polarization frame of reference of the receiver.

A power amplification apparatus, a remote radio unit, and a base station are provided to improve power amplification efficiency. The power amplification apparatus includes an envelope modulator, a main power amplifier, and a first auxiliary power amplifier. The envelope modulator is configured to obtain an envelope voltage based on a received envelope signal and output the envelope voltage to the drain of the main power amplifier. The main power amplifier is connected to the envelope modulator and configured to use the envelope voltage as an operating voltage, and is connected to the first auxiliary power amplifier, to output the envelope voltage to a drain of the first auxiliary power amplifier. The first auxiliary power amplifier is configured to use the envelope voltage received from the main power amplifier as an operating voltage.

A system and method for packaging a semiconductor device that includes a wall to reduce electromagnetic coupling is presented. A semiconductor device has a substrate on which a first circuit and a second circuit are formed proximate to each other. An isolation wall of electrically conductive material is located between the first circuit and the second circuit, the isolation wall being configured to reduce inductive coupling between the first and second circuits during an operation of the semiconductor device. Several types of isolation walls are presented.

The present invention relates to a novel and inventive compound device structure for a low noise current amplifier or trans-impedance amplifier. The trans-impedance amplifier includes an amplifier portion, which converts current input into voltage using a complimentary pair of novel n-type and p-type current field-effect transistors (NiFET and PiFET) and a bias generation portion using another complimentary pair of NiFET and PiFET. Trans-impedance of NiFET and PiFET and its gain may be configured and programmed by a ratio of width (W) over length (L) of source channel over the width (W) over length (L) of drain channel (W/L of source channel/W/L of drain channel).

Provided is a power amplification circuit that includes: a first transistor that has an emitter to which a first radio frequency signal is supplied, a base to which a first DC control current or DC control voltage is supplied and a collector that outputs a first output signal that corresponds to the first radio frequency signal; a first amplifier that amplifies the first output signal and outputs a first amplified signal; and a first control circuit that supplies the first DC control current or DC control voltage to the base of the first transistor in order to control output of the first output signal.

Embodiments of the present invention provide a power amplifier, a radio remote unit RRU, and a base station. A multiphase pulse width modulator performs modulation to generate N multiphase pulse-width modulation PWM signals. The multiphase pulse-width modulation PWMn signal may be amplified. The multiphase pulse-width modulation PWMn signal may be filtered and a combination may be performed at a drain or a collector of a power amplifier transistor. According to the new radio frequency amplifier in accordance with the disclosure, envelope feeding loop inductance can be effectively reduced, so that video bandwidth is increased and DPD correction performance is improved.