Abstract: An apparatus and method for improving the efficiency of a power amplifier operating on the basis of a signal of a large peak-to-average power ratio (PAR). A main amplification part detects envelope values of an input baseband signal, reduces a peak value of the envelope values of the baseband signal to generate a peak reduced signal, amplifies the generated peak reduced signal, and outputs a first amplified signal. An error correction amplification part amplifies an error signal indicating a difference between the baseband signal and the peak reduced signal, and outputs a second amplified signal. A summing part combines the first amplified signal from the main amplification part and the second amplified signal from the error correction amplification part, such that high amplification efficiency is produced and an amplified output signal with reduced spectral regrowth in which an error is corrected can be outputted.

Abstract: A power amplification controlling apparatus and method in a mobile communication system are provided. An amplifying part amplifies an input Radio Frequency (RF) signal with a power supply voltage. A bias adaptation part detects a change in at least one an operation and an environment of the amplifying part, attenuates the RF signal according to the detected change, detecting the envelope of the attenuated signal, and generates a supply voltage control signal according to the envelope. A power supply part changes the power supply voltage in response to the supply voltage control signal.

Abstract: A method is provided for transmitting a signal in a signal transmission apparatus of a communication system. Upon receiving a signal, the signal transmission apparatus determines a mode of the received signal, in which a power amplifier should amplify the signal; generates a mode control signal corresponding to a single mode, if the mode of the received signal is determined as the single mode; amplifies and transmits the received signal in the single mode according to the mode control signal; generates a mode control signal corresponding to a multi-mode, if the mode of the received signal is the multi-mode; and amplifies and transmits the received signal in the multi-mode according to the mode control signal.

Abstract: A power amplification controlling apparatus and method in a mobile communication system are provided. An amplifying part amplifies an input Radio Frequency (RF) signal with a power supply voltage. A bias adaptation part detects a change in at least one an operation and an environment of the amplifying part, attenuates the RF signal according to the detected change, detecting the envelope of the attenuated signal, and generates a supply voltage control signal according to the envelope. A power supply part changes the power supply voltage in response to the supply voltage control signal.

Abstract: A power amplification controlling apparatus and method in a mobile communication system are provided. An amplifying part amplifies an input Radio Frequency (RF) signal with a power supply voltage. A bias adaptation part detects at least one of environmental changes of the amplifying part, attenuates the RF signal according to the detected environmental change, detecting the envelope of the attenuated signal, and generates a supply voltage control signal according to the envelope. A power supply part changes the power supply voltage in response to the supply voltage control signal.

Abstract: Provided is an apparatus for protecting a receiver circuit in a Time Division Duplexing (TDD) wireless communication system. In the protecting apparatus, an antenna switch transmits an output signal of a power amplifier to an antenna feed line and transmits an output signal of the antenna feed line to a low noise amplifier. A status monitor monitors a status of the antenna switch. A mode determiner disables an amplification operation of the power amplifier when a status monitoring signal outputted from the status monitor is an RX mode. Accordingly, the low noise amplifier can be protected from being damaged by the mismatch between the TX signal and the TDD control signals in the system initialization, assembly/disassembly of the boards, and any abnormal environments including the abnormality of the control signal generator.

Abstract: A method and an apparatus for amplifying power in a communication system is disclosed that includes a detection module which detects a power level of a predetermined signal selected from among an input signal and an output signal of a power amplifier and then transmits an operation mode control signal for the power amplifier; a gate bias controller which controls a gate bias of the power amplifier in accordance with the detected power level; and a power amplifier which operates as class B or class A in accordance with control by the gate bias controller to generate a pre-distortion component, offsets a distortion component generated during amplification of the predetermined signal by synthesizing the pre-distortion component with the distortion component, and outputs only the predetermined signal without a distortion component.

Abstract: Provided is a TRAS in a TDD wireless communication system. In the TRAS, a circulator transmits a signal received from a PA to an antenna feed line and a signal received from the antenna feed line to a reflector. The reflector fully reflects the signal received from the circulator when a reflection operation is turned on in transmission mode, and transmits the signal received from the circulator to a wireless switch, such as, an RF switch when the reflection operation is turned off in reception mode. The RF switch transmits or blocks the signal received from the reflector to or from an LNA according to the transmission or reception mode.

Abstract: A system and method for transmitting a signal in a communication system are provided. In the signal transmitting method, a multi-FA signal is generated by combining single FA signals to be transmitted by N FAs. An operation mode is determined for N MMPAs according to a used FA strategy and adjustment of amplification characteristics of the N MMPAs is controlled according to the operation mode. The power of the multi-FA signal is divided by N, the N divided signals are amplified according to the adjusted amplification characteristics, and the power of the amplified N signals is combined.

Abstract: A transmitting apparatus in a TDD wireless communication system is provided. In the transmitting apparatus, a circulator transmits a signal received from a power amplifier to an antenna feed line and transmits a signal received from the antenna feed line to a quarter-wave transmission line. The quarter-wave transmission line is installed in a reception path, for reception isolation in a transmission mode. An RF switch shorts the load of the quarter-wave transmission line to the ground or connects the load of the quarter-wave transmission line to an LNA according to a control signal. The LNA low-noise-amplifies a signal received from the RF switch.

Abstract: A power amplification apparatus and method for amplifying a baseband signal having a high peak-to-average power ratio (PAR) are provided. The power amplification apparatus and method comprise a signal generation section for generating a peak-reduced signal obtained by subtracting a peak value from the baseband signal and an error signal representing a difference between the baseband signal and the peak-reduced signal and for outputting the generated signals; a peak-reduced signal amplification section for amplifying the peak-reduced signal output from the signal generation section in a radio frequency band; an error correction amplification section for amplifying the error signal output from the signal generation section in the radio frequency band; and a summer for coupling and outputting the signal amplified by the peak-reduced signal amplification section and the signal amplified by the error correction amplification section.

Abstract: A power amplification controlling apparatus and method in a mobile communication system are provided. An amplifying part amplifies an input Radio Frequency (RF) signal with a power supply voltage. A bias adaptation part detects at least one of environmental changes of the amplifying part, attenuates the RF signal according to the detected environmental change, detecting the envelope of the attenuated signal, and generates a supply voltage control signal according to the envelope. A power supply part changes the power supply voltage in response to the supply voltage control signal.

Abstract: An apparatus and method for improving the efficiency of a power amplifier operating on the basis of a signal of a large peak-to-average power ratio (PAR). A main amplification part detects envelope values of an input baseband signal, reduces a peak value of the envelope values of the baseband signal to generate a peak reduced signal, amplifies the generated peak reduced signal, and outputs a first amplified signal. An error correction amplification part amplifies an error signal indicating a difference between the baseband signal and the peak reduced signal, and outputs a second amplified signal. A summing part combines the first amplified signal from the main amplification part and the second amplified signal from the error correction amplification part, such that high amplification efficiency is produced and an amplified output signal with reduced spectral regrowth in which an error is corrected can be outputted.