Abstract:
A method and an apparatus for CQI(Channel Quality Indicator) control for adaptive modulation and coding in an OFDMA system improve capacity and fairness of the OFDMA system by variably controlling a size of a sub carrier group. A valid cluster is selected among clusters including one bin or more which are a plurality of subcarrier groups according to a predetermined standard(S335). An average CINR(Carrier-to-Interference-plus-Noise Ratio) of the valid cluster is calculated(S337). The optimum MCS level of each valid cluster is determined based on the average CINR value(S353). The optimum cluster among the valid clusters is determined based on the optimum MCS level(S373).
Abstract:
Provided is a method and apparatus improving a deterioration of a gain flatness and a phase characteristic that may be incurred while a baseband signal is transformed into a immediate frequency (IF) signal and a radio frequency (RF) signal in a broadband wireless communication system. A sub-band extractor may divide the broadband signal into multiple sub-band signals, may pre-compensate for a gain and a phase delay of each sub-band signals in the baseband, and may combine the pre-compensated sub-band signals into the single broadband signal and thus, the deterioration of the gain flatness and a phase delay flatness that may be incurred while the broadband signal is transformed into the IF signal and the RF to signal, may be improved.
Abstract:
본 발명에 의한 모드 변환 기능이 내장된 안테나는 개구면이 직사각형 형태인 혼(horn) 형상의 혼 안테나부; 및 상기 혼 안테나부의 개구면 반대쪽에서 상기 혼 안테나부의 내부에 위치하며 상기 안테나부와 마이크로 스트립 전송선을 연결하는 적어도 하나 이상의 모드 변환부;를 포함하는 것을 특징으로 하며 마이크로파 및 밀리미터파 대역에서 동작 가능하며 종래에 사용하는 혼 안테나의 제작 방식을 사용하지 않고 정전기 방전에 의한 영향을 차단함으로써 송수신 모듈의 신뢰성을 개선할 수 있으며, 송수신 모듈과 안테나를 연결할 때 발생할 수 있는 제작 오차를 줄일 수 있다.
Abstract:
PURPOSE: A method and an apparatus for generating a pre-distortion signal are provided to extract distortion components of a transmitter by using a reception signal of a reception unit. CONSTITUTION: A reception unit(210) receives a first signal including a distortion signal generated in a transmitter and a transmission signal of a transmission unit(200). The reception unit detects a distortion signal from the first signal, and transmits the information on the detected distortion signal with the first signal. The transmission unit generates a pre-distortion signal by using the first signal and the information on the distortion signal received from the receiver. The transmission unit combines the generated pre-distortion signal with the transmission signal.
Abstract:
PURPOSE: A transceiver using a millimeter wave is provided to predict a loss value easily by determining the output power of a transmission signal based on a reception signal of a receiving end. CONSTITUTION: A transmitter(450) generates a transmission signal from an input signal, and a receiver(480) restores the reception signal received by an antenna. A power detector(417) outputs a control signal to control the output power of the transmission signal based on the power of the reception signal, and an IF upstream mixer(404) of the transmitter up-mixes the analog signal converted from the input signal with an IF local oscillator output signal.
Abstract:
본원발명은 전압 제어 발진기에 관한 것으로, 차등 신호를 발진하기 위해 교차 결합되거나 대칭형으로 구성된 한 쌍의 FET 및 인덕터로 구성된 발진부; 상기 발진부의 출력을 증폭하는 한 쌍의 FET로 구성된 증폭부; 및 상기 증폭부의 한 쌍의 각 FET 소스 단자에 끝이 단락되어 연결된 전송선을 포함하는 것을 특징으로 함으로써, 버퍼 증폭기의 이득을 이용하여 출력을 높일 수 있도록 한다.
Abstract:
PURPOSE: A relay terminal for cell information exchange between adjacent base stations in a cellular system is provided to directly transmit operation information and coexistence information to cells, thereby effectively controlling multi cells. CONSTITUTION: Each transceiving device comprises the following units. An address filter(905) classifies cell information. A mutual work function execution unit transmits the cell information to another transceiving device through an interface. The mutual work function execution unit receives cell information which sets a base station of the cell information as a transmission address from another transceiving device.
Abstract:
본 발명은 인지 무선(Cognitive Radio) 시스템에서의 채널 스위칭 방법, 주파수채널을 관리하는 방법, 이를 이용하는 기지국 및 단말에 관한 것으로, 본 발명에 따른 기지국의 채널 스위칭 방법은 단말과의 통신 채널로 설정된 적어도 하나의 상/하향링크 주파수채널 중에서, 현재 사용될 수 없는 제1 주파수채널을 검출하는 검출단계; 상기 제1 주파수채널에서 제2 주파수채널로 전환하라는 채널스위칭요구메시지를 상기 단말에게 송신하는 채널스위칭요구메시지송신단계; 및 상기 단말로부터, 상기 채널스위칭요구메시지에 따라 채널전환한다는 채널스위칭보고메시지를 수신하면, 상기 제1 주파수채널에서 상기 제2 주파수채널로 전환하는 채널스위칭단계를 포함한다. 본 발명에 따르면, 원래 사용자를 보호함과 동시에 효율적인 채널 변환을 수행할 수 있다. Cognitive radio, WRAN(Wireless Regional Area Network), FDD(Frequency Division Duplexing), TDD(Time Division Duplexing), Channel Switching, Incumbent Protection, Implicit Signaling, Explicit Signaling, Out-band Signaling, OFDM, Channel Scan, Channel Matching, Channel Grouping.명세서
Abstract:
A switched beam forming apparatus is provided to enhance system efficiency and a signal to noise ratio, and improve a signal separation characteristic by reducing power consumption while maximizing an impedance value. A switched beam forming apparatus includes a plurality of antenna devices(101), a switched beam forming circuit(102), a plurality of frequency converters(104), a plurality of switches(107), and a decoding unit and a baseband unit(106). The antenna devices have a plurality of directionalities. The switched beam forming circuit separates signals received from the antenna devices into a plurality of independent beams to output the beams. The frequency converters mixes signals passing through a plurality of paths outputted from the switched beam forming circuit with signals outputted from a local oscillator. The switches connect signals of N-1 paths excluding the signals outputted from the frequency converters to resistors(108). The decoding unit and the baseband unit receive only one directional signal which is not connected to the switches and the resistor from the frequency converters and decode the received signal.