A network interface device includes an active path between an entry port and a first input/output port. The network interface device also includes a passive path between the entry port and a second input/output port. The network interface device also includes a buffer in the active path configured to absorb, attenuate, terminate, or isolate radio-frequency (RF) signals. The network interface device also includes a switching element in the active path configured to selectively bypass the buffer during normal operating conditions.

A network interface device includes an active path between an entry port and a first input/output port. The network interface device also includes a passive path between the entry port and a second input/output port. The network interface device also includes a buffer in the active path configured to absorb, attenuate, terminate, or isolate radio-frequency (RF) signals. The network interface device also includes a switching element in the active path configured to selectively bypass the buffer during normal operating conditions.

An electronic device is provided. The electronic device includes a communication module and a processor electrically connected to the communication module, wherein the communication module includes an antenna configured to transmit and receive a communication signal, a sensor configured to measure an impedance of the antenna, and a first matching circuit and a second matching circuit electrically connected to the antenna, and the processor is configured to receive information on the impedance of the antenna from the sensor, check control information on at least one of the first matching circuit and second matching circuit corresponding to the impedance of the antenna at least partially based on the received information on the impedance of the antenna, and transmit control information generated at least partially based on the checked control information to at least one of the first matching circuit and the second matching circuit corresponding to the control information.

An electronic device is provided. The electronic device includes a communication module and a processor electrically connected to the communication module, wherein the communication module includes an antenna configured to transmit and receive a communication signal, a sensor configured to measure an impedance of the antenna, and a first matching circuit and a second matching circuit electrically connected to the antenna, and the processor is configured to receive information on the impedance of the antenna from the sensor, check control information on at least one of the first matching circuit and second matching circuit corresponding to the impedance of the antenna at least partially based on the received information on the impedance of the antenna, and transmit control information generated at least partially based on the checked control information to at least one of the first matching circuit and the second matching circuit corresponding to the control information.

A power amplifier module includes a first current source that outputs a first current corresponding to a level control voltage for controlling a signal level of an amplified signal, a second current source that outputs a second current corresponding to the level control voltage, a first transistor in which an input signal and a first bias current are supplied to a base and an emitter is grounded, a second transistor in which an emitter is connected to a collector of the first transistor, the second current is supplied to a base, and a first amplified signal obtained by amplifying the input signal is output from a collector, and a third transistor in which the first current is supplied to a collector, a bias control current or voltage is supplied to a base, and the first bias current is supplied from an emitter to the base of the first transistor.

A power amplifier module includes a first current source that outputs a first current corresponding to a level control voltage for controlling a signal level of an amplified signal, a second current source that outputs a second current corresponding to the level control voltage, a first transistor in which an input signal and a first bias current are supplied to a base and an emitter is grounded, a second transistor in which an emitter is connected to a collector of the first transistor, the second current is supplied to a base, and a first amplified signal obtained by amplifying the input signal is output from a collector, and a third transistor in which the first current is supplied to a collector, a bias control current or voltage is supplied to a base, and the first bias current is supplied from an emitter to the base of the first transistor.

A polar transmitter includes an amplitude path comprising an amplitude signal that corresponds to an amplitude of a vector sum of an in-phase input signal and a quadrature input signal; a phase path comprising a phase modulator configured to phase-modulate a phase signal that corresponds to the phase of the vector sum of the in-phase input signal and the quadrature input signal; a digital power amplifier (DPA) configured to amplify the phase-modulated (PM) input signal based on the amplitude signal; a tunable matching network coupled to an output of the DPA and configured to adjust a load impedance of the DPA; and a controller configured to adjust the matching network based on a look-up table with respect to amplitude and frequency information, where the look-up table indicates a plurality of optimal operation modes of the matching network for specific combinations of amplitude and frequency information.

Provided is a power amplification circuit that includes: an amplifier that amplifies an input signal and outputs an amplified signal; a first bias circuit that supplies a first bias current or voltage to the amplifier; a second bias circuit that supplies a second bias current or voltage to the amplifier; a first control circuit that controls the first bias current or voltage; and a second control circuit that controls the second bias current or voltage. The current supplying capacity of the first bias circuit is different from the current supplying capacity of the second bias circuit.

Provided is a power amplification circuit that includes: an amplifier that amplifies an input signal and outputs an amplified signal; a first bias circuit that supplies a first bias current or voltage to the amplifier; a second bias circuit that supplies a second bias current or voltage to the amplifier; a first control circuit that controls the first bias current or voltage; and a second control circuit that controls the second bias current or voltage. The current supplying capacity of the first bias circuit is different from the current supplying capacity of the second bias circuit.

Power amplification system with adjustable common base bias. A power amplification system can include a cascode amplifier coupled to a radio-frequency input signal and coupled to a radio-frequency output. The power amplification system can further include a biasing component configured to apply one or more biasing signals to the cascode amplifier, the biasing component including a bias controller and one or more bias components. Each respective bias component may be coupled to a respective bias transistor.