Abstract: An apparatus and a method for an Envelope Elimination and Restoration (EER) power transmitter are provided. The apparatus includes a signal separator for splitting a transmit signal to an amplitude component and a phase component, an orthogonal modulator for modulating the phase component into a Radio Frequency (RF) signal, a bias modulator for linearly amplifying the amplitude component, for determining a bias voltage according to a magnitude of the amplitude component, and for providing a current generated using the determined bias voltage to a high-efficiency power amplifier and the high-efficiency power amplifier for amplifying the RF signal using the linearly amplified amplitude component as a drain bias voltage and using the generated current as a drain bias current.

Abstract: A saturated power amplification apparatus and a method for controlling the same are provided, in which a power device is provided, and an output matcher matches a load impedance of the power device. The load impedance is a complex impedance exceeding an impedance generated during power matching in the saturated power amplification apparatus.

Abstract: A Radio Frequency (RF) front-end apparatus in a wireless communication system is provided. The apparatus includes a plurality of BandPass Filters (BPFs) for band-pass filtering a transmission signal or a reception signal, at least one circulator for dividing a signal transmission path and a signal reception path and at least one switch for controlling the signal transmission path and the signal reception path. The RF front-end apparatus provided by the present invention supports various frequency bands and optionally supports TDD and FDD in a wireless communication system.

Abstract: A saturated power amplification apparatus and a method for controlling the same are provided, in which a power device is provided, and an output matcher matches a load impedance of the power device. The load impedance is a complex impedance exceeding an impedance generated during power matching in the saturated power amplification apparatus.

Abstract: An apparatus and a method for an Envelope Elimination and Restoration (EER) power transmitter are provided. The apparatus includes a signal separator for splitting a transmit signal to an amplitude component and a phase component, an orthogonal modulator for modulating the phase component into a Radio Frequency (RF) signal, a bias modulator for linearly amplifying the amplitude component, for determining a bias voltage according to a magnitude of the amplitude component, and for providing a current generated using the determined bias voltage to a high-efficiency power amplifier and the high-efficiency power amplifier for amplifying the RF signal using the linearly amplified amplitude component as a drain bias voltage and using the generated current as a drain bias current.

Abstract: A Radio Frequency (RF) front-end apparatus in a wireless communication system is provided. The apparatus includes a plurality of BandPass Filters (BPFs) for band-pass filtering a transmission signal or a reception signal, at least one circulator for dividing a signal transmission path and a signal reception path and at least one switch for controlling the signal transmission path and the signal reception path. The RF front-end apparatus provided by the present invention supports various frequency bands and optionally supports TDD and FDD in a wireless communication system.

Abstract: An apparatus and a method are provided for detecting asynchronous transmission in a wireless communication system. In a transmitter, a correlator correlates a baseband transmission sample signal with a preamble signal. A decider detects a peak among correlations received from the correlator and determines whether transmission of the transmission sample signal is asynchronous by comparing a frame reference time with a detection time of the peak.

Abstract: A TDD transceiver for utilizing a Tx mode and an Rx mode simultaneously and a self-diagnostic method therefor. In the TDD transceiver, a transmitter transmits a Tx signal from a Tx path to an antenna. A receiver for processes an Rx signal to a baseband signal. A detector couples the Tx signal in the transmitter and provides the coupled Tx signal to the receiver. A diagnostic portion determines if the TDD transceiver is normal or abnormal using the Tx signal received from the receiver.

Abstract: An apparatus for receiving signals in a base station of a CDMA communication system including a first and a second subordinate base station (Pico-BTS) having a small capacity, each including a transmission-reception antenna, a duplexer connected to the antenna, a transmitter for transmitting a signal through the duplexer to the antenna, a main receiver for receiving a signal from the antenna through the duplexer, and an auxiliary receiver, wherein the main receiver of each of the first and second Pico-BTS divides the signal from the antenna into two subordinate signals, one of which is applied to the main receiver in a normal way and the other is applied to the auxiliary receiver of another Pico-BTS.

Abstract: An output control unit of a mobile communication system includes a transmit up-converter board having first and second mixers responsive to first and second oscillation frequency signals, respectively, for up-converting the frequency of a transmission signal, an attenuator installed between the transmit up-converter board and a final output terminal for controlling output of the up-converted transmission signal order to eliminate unwanted signal characteristic irrespective of amplification and attenuation when the transmission signal is up-converted for transmission and a transceiver slave control unit responsive to the second oscillation frequency signal for generating a control signal for controlling the attenuator, wherein the transceiver slave control unit utilizes an interface unit controlled to produce phase locked loop control data for controlling a local oscillator to generate the second local oscillation frequency of a designated channel, wherein the local oscillator informs the interface unit that i