Abstract: The present invention relates to a wireless transceiver system for supporting a dual mode that simultaneously supports the Frequency Division Duplex (FDD) method and the Time Division Duplex (TDD) method in a certain frequency band. The present system supports the FDD system conducting transmission and reception simultaneously by using different frequency bands for transmission and reception as well as the TDD system temporally alternating transmission and reception by using the common frequency band among an upper frequency band and a lower frequency band used in the FDD system as well as another frequency band adjacent thereto, thereby selectively supporting both of the two communication systems in a wireless transceiver system.

Abstract: The present invention relates to a wireless transceiver system for supporting a dual mode, and more particularly to a wireless transceiver system for supporting a dual mode that simultaneously supports the Frequency Division Duplex (FDD) method and the Time Division Duplex (TDD) method in a certain frequency band. The present system supports the FDD system conducting transmission and reception simultaneously by using different frequency bands for transmission and reception as well as the TDD system temporally alternating transmission and reception by using the common frequency band among an upper frequency band and a lower frequency band used in the FDD system as well as another frequency band adjacent thereto, thereby selectively supporting both of the two communication systems in a wireless transceiver system.

Abstract: Provided are a PLL apparatus for an OFDM system having variable channel band and an operating method thereof. The PLL apparatus includes a frequency divider for dividing an oscillating signal; a phase detector for detecting a phase difference between a reference signal and the divided oscillating signal from the frequency divider and outputting the phase difference signal; a variable loop filter for filtering a phase difference signal outputted from the phase detector; a voltage control oscillator for outputting the oscillator signal to the frequency divider according to the voltage control signal filtered from the variable loop filter; and a variable loop filter controller for varying a filtering band of the variable loop filter according to each of the channel bands.

Abstract: The present invention relates to a scalable bandwidth system and a method of controlling a tunable filter. In the present invention, the scalable bandwidth system inputs, as a control signal of a tunable filter, a voltage corresponding to a section in which the capacitance according to an applied voltage is not practically changed for characteristics of varactor diodes, and inputs each control bit of the control signal to each varactor diode of the tunable filter to adjust the capacitance of each of the varactor diodes, and consequently adjusts the capacitance of the tunable filter by adding the capacitance of the varactor diodes.

Abstract: The present invention relates to an RF repeater used in a time division method, and a method thereof. An RF repeater according to an exemplary embodiment of the present invention receives a downlink signal that is to be transmitted from a base station to a mobile terminal, performs first automatic gain control on the downlink signal, and extracts gain information from the downlink signal on which the first automatic gain control has been performed, on the basis of gain variation information that is the gain information for the downlink signal. Then, the RF repeater performs second automatic gain control on the downlink signal on the basis of the extracted gain information, and performs a control operation such that the downlink signal on which the second automatic gain control has been performed is transmitted to the mobile terminal.

Abstract: Provided are a PLL apparatus for an OFDM system having variable channel band and an operating method thereof. The PLL apparatus includes a frequency divider for dividing an oscillating signal; a phase detector for detecting a phase difference between a reference signal and the divided oscillating signal from the frequency divider and outputting the phase difference signal; a variable loop filter for filtering a phase difference signal outputted from the phase detector; a voltage control oscillator for outputting the oscillator signal to the frequency divider according to the voltage control signal filtered from the variable loop filter; and a variable loop filter controller for varying a filtering band of the variable loop filter according to each of the channel bands.