Abstract:
PURPOSE: A system for managing the interference of a control channel is provided to reduce interference between adjacent cells in an environment where different kind of cell is mixed and to allocate wireless resources to transmit a control channel to a macro terminal with reference to wireless information which is received from a femto base station. CONSTITUTION: A femto base station allocates a radio resource about a control channel(410). The femto base station transmits allocated wireless resource information to a macro base station(420). The femto base station transmits a cell ID to the macro base station(430). Wireless resource information is used for allocating a wireless resource about a control channel of the macro base station. The cell ID is a physical layer cell ID or a global ID.
Abstract:
PURPOSE: A system controlling interference between cells in a cellular mobile communication system is provided to use cooperation transmission mode, thereby reducing the intensity of interference between cells transmitted form cooperation cell to a terminal. CONSTITUTION: A receiving unit(410) receives information about a first channel between a serving cell and a terminal and information about a second channel between a cooperated cell neighboring to the serving cell and the terminal form the terminal. A transmission mode determiner(420) determines a cooperated transmission mode with the cooperation cell about the terminal based on information about the first and the second channel. A transmission unit(430) transmits data to the terminal according to the cooperation transmission mode.
Abstract:
본 발명은 이동 단말기가 아이들 모드(Idle mode)에서 자신에게 할당된 페이징 유효 구간(paging available interval) 구간에 깨어나서 페이징 인디케이터(paging indicator) 검출을 수행하기 위한 동기를 획득하는 단계와, 상기 동기 획득 결과에 따라 현재 페이징 유효 구간과 이전 페이징 유효 구간의 서빙(serving) 기지국이 다른 경우, 페이징 제어(paging control) 정보를 획득하는 단계와, 상기 동기 획득 결과에 따라 현재 페이징 유효 구간과 이전 페이징 유효 구간의 서빙(serving) 기지국이 동일한 경우, 자신이 속한 이동 단말기 그룹에 해당하는 페이징 인디케이터를 검출하는 단계 및 상기 검출된 페이징 인디케이터를 이용하여 페이징 제어 정보 획득 여부를 판단하는 단계를 포함하는 페이징 인디케이터 검출 방법을 제공한다. 페이징 인디케이터, 전송, 검출, 아이들 모드
Abstract:
이동통신 시스템에서의 수신확인신호의 송수신장치 및 방법이 개시된다. 수신장치 및 방법은 미리 설정된 요구 패킷 오류율에 따라 예측된 예상 패킷 오류율을 이용하여 수신된 수신확인신호가 수신성공신호일 확률 및 수신실패신호일 확률을 각각 계산하여 수신확인신호가 수신성공신호 또는 수신실패신호인지 여부를 판단한다. 송신장치 및 방법은 수신된 패킷 데이터의 전송전력 및 미리 설정된 요구 패킷 오류율을 기초로 패킷 데이터의 수신성공여부에 대한 수신확인신호 중 수신성공신호를 변조한 제1복소 신호 및 수신실패신호를 각각 변조한 제2복소 신호의 차이가 최대화되도록 수신성공신호 및 수신실패신호의 송신전력을 달리하여 전송하고, 적어도 하나 이상의 패킷 데이터의 수신 성공여부를 나타내는 수신확인신호들을 미리 설정된 요구 패킷 오류율을 이용하여 다른 길이의 부호를 할당하는 가변길이 부호의 단일패킷으로 전송한다. 본 발명에 따르면, 수신성공신호 및 수신실패신호의 비균일성을 고려하여 수신확인신호의 수신 성공률을 높인다. ACK/NACK, 사전확률분포(prior probability distribution), 사후확률분포( posterior probability distribution), 허프만 코드(Huffman code)
Abstract:
PURPOSE: A method and an apparatus for detecting a paging indicator in an orthogonal frequency division based mobile communication system are provided to transmit a paging indicator using a preamble, thereby transmitting a paging indicator without increasing overhead. CONSTITUTION: A method for detecting a paging indicator in an orthogonal frequency division based mobile communication system comprises the following steps. A mobile terminal(110,120) is waked up during a paging available interval assigned to the mobile terminal from an idle mode, synchronization for detecting a paging indicator is obtained. When serving base stations of a current paging available interval and a previous paging available interval are different according to a synchronization obtaining result, paging control information is obtained.
Abstract:
An apparatus and a method for channel estimation and synchronization in an OFDM/OFDMA relay system are provided to improve the deterioration of the channel estimation performance due to delay by estimating a channel between a transmitter and a terminal when receiving data through a relay. A synchronizing device includes an offset storage(1210), a transmission device identifier(1220), a compensator(1230), an estimator and an updating unit. The offset storage stores the carrier frequency offset between each transmission device and the terminal and the timing offset. The transmission device identifier identifies the transmission device transmitting the signal when receiving the signal. The compensator compensates for the carrier frequency offset and the timing offset about the received signal. The estimator estimates the carrier frequency offset and the timing offset between the transmission device and the terminal. The updating unit updates the carrier frequency offset and the timing offset of the identified transmission device stored in an offset storage by the estimated carrier frequency offset and timing offset.
Abstract:
본 발명은 직교주파수분할다중접속(OFDMA) 통신 시스템과 같은 다중 반송파 무선 시스템에서 채널 품질 정보(CQI)를 피드백하기 위해 채널 품질 정보의 보고 주기를 결정하는 방법 및 장치에 관한 것으로, 직교주파수 분할다중 접속(OFDMA)을 기반으로 하는 단말에서의 채널 품질 정보의 피드백을 위한 보고 주기 결정 방법에 있어서, (a) 기지국으로부터 수신된 채널을 통해 채널 이득을 계산하는 단계; (b) 공평성 정도를 결정짓는 변수와 상기 계산된 채널 이득을 이용해 가중치를 계산한 다음 상기 계산된 가중치를 이용해 상기 계산된 채널 이득에 대한 가중 채널 품질을 계산하는 단계; (c) 상기 계산된 가중 채널 품질과 임계치를 비교하는 단계; 및 (d) 상기 가중 채널 품질이 상기 임계치 이상인 경우에만 채널 품질 정보의 피드백을 위해 할당된 무선 자원을 이용해 측정된 채널 품질 정보를 피드백하는 단계를 포함한다. OFDMA, 직교, 주파수, 분할, 다중, CQI, 채널 품질, 피드백, 주기, 전송, 가중 채널 품질
Abstract:
An apparatus and a method for channel estimation and synchronization in an OFDM/OFDMA(Orthogonal Frequency Division Multiplexing Access) relay system are provided to estimate a channel by estimating a propagation delay weight using a conventional pilot signal without a training signal. An apparatus for channel estimation and synchronization in an OFDM/OFDMA relay system includes a pilot extraction unit(410), a propagation delay estimation unit(430), and a weight value estimation unit(440). The pilot extraction unit extracts pilot signals based on a frequency domain signal which is Fourier-transformed after a signal received from a transparent relay is synchronized with a reference signal received from a base station. The propagation delay estimation unit estimates a propagation delayer between the transparent relay and a terminal based on the extracted pilot signal and the reference pilot signal as a predetermined signal value corresponding to the extracted pilot signal. The weight value estimation unit estimates a propagation delay weight value for estimating a channel between the terminal and the transparent relay based on the estimated propagation delay.
Abstract:
An apparatus and a method for transmitting/receiving multi-code word in an SC-FDMA(Single Carrier-Frequency Division Multiple Access) are provided to reduce an interference between symbols in a frequency selective fading environment. A demultiplexer divides a data stream of a user into the M number of sub-streams(S210). The M number of encoders and the M number of QAM(Quadrature Amplitude Modulation) mappers independently perform channel coding and QAM mapping on each of the M number of sub-streams(S220). The M number of QAM-mapped sub-streams are mapped to DFT(Discrete Fourier Transform) indexes by using a DFT mapper(S230). The DEF mapper applies DFT to the mapped signals(S240). The DFT-applied signals are mapped to sub-carriers corresponding to the user by using a sub-carrier mapper(S250). IFFT(Inverse Fast Fourier Transform) is applied to the sub-carrier mapped result signals, which are then transmitted via a transmission antenna(S260).
Abstract:
A method and an apparatus for determining a report period of channel quality information in a multi-carrier wireless system are provided to improve the report success probability of a user in a good channel state by differently giving a report period of CQI(Channel Quality Information) according to a channel state measured by every user terminal. A user terminal receives a factor for determining an equality degree used for each user terminal and various variables such as a threshold value given to each terminal according to priority levels from a base station and stores them in a memory(201). The user terminal calculates a channel gain by using a pilot signal received from the base station(202). The user terminal calculates a statistical expected value with respect to the calculated channel gain, calculates a weight value by using the factor determining the degree of equality, and calculates a weighted channel quality by multiplying the calculated weight value and the channel gain(203). A CQI transmission determining unit of the user terminal compares the calculated weighted channel quality with the received threshold value(204). If the calculated weighted channel quality is larger than the threshold value, the user terminal feeds back the measured channel quality information to the base station(205).