Abstract:
An apparatus and a method for controlling power are provided to control the transmitting power of a terminal in the outside of an FLR(full loading range) by applying power concentration gain according to a distance between a base station and a terminal to a transmitting signal of a modulator. An apparatus for controlling power in a communication system comprises a power amplifier(400), a power controller(500), and a gain controller(200). The power amplifier amplifies transmitting power of a transmitting signal. The power controller controls a gain of the power amplifier using a receiving signal. The gain controller measures a distance between a transmitter transmitting the receiving signal and the apparatus for controlling power, and applies a power concentration gain according to the distance to the transmitting signal.
Abstract:
An apparatus and a method for acquiring synchronization in a mobile communication system are provided to correct synchronization mismatch with other base stations previously by generating a compound clock by itself to be used for the synchronization or compensating for the generated compound clock based on a reception signal when a signal received from an external region is minute such as a noise level. A method for acquiring synchronization for communication with a peripheral device in a mobile communication system comprises the following steps of: generating at least one compound clock having different period and timing offset(S204); searching a period of a preamble from at least one received signal having the preamble and data(S206); searching a usable preamble period as a reference in compensation of the generated compound clock from the searched period of the preamble(S207); and searching the compound clock having the same period as the preamble period as the reference from the generated compound clock and using the searched compound clock as a synchronization signal(S208,S209).
Abstract:
A MIMO(Multi-Input Multi-Output) system of space-time codes using an orthogonal sequence is provided to solve a problem that if there are three or more transmission antennas, space-time codes maintaining orthogonality cannot satisfy a maximum transmission rate, and a decoding complexity is high. A plurality of transmission processors(102) correspond to a plurality of transmission antennas(103). A serial/parallel conversion unit(101) space-time codes input data to generate parallel data corresponding to the plural transmission processors. A real number component processor(110) orthogonal-coding-processes real number component data of corresponding among the parallel data from the serial/parallel conversion unit. An imaginary number component processor(120) orthogonal-coding-processes imaginary number component data of corresponding data among the parallel data from the serial/parallel conversion unit. A synthesizing unit(130) synthesizes output data of the real number component processor and the imaginary number component processor in order to transmit the same via a corresponding transmission antenna. Mappers(111,121) generate a real number component and an imaginary number component of the data, which are inputted through the serial/parallel conversion unit, in non-binary signal value.
Abstract:
An up-link framing apparatus in a mobile communication system and an up-link framing method of the same are provided to minimize an up-link framing period in a system for supporting a shift frame block. A high MAC unit sets a connecting state with a base station. The high MAC unit receives, buffers, and stores a data packet from an upper layer. The high MAC unit generates SDU header information on the buffered data packet and generates MAC PDU. A low MAC unit receives and stored the SDU from the high MAC unit. The low MAC unit stores circular queue head and tail pointer information, analyzes an up-link map received from the base station, and reports an assigning state of a radio resource to the high MAC unit.
Abstract:
본 발명은 OFDMA 시스템에서 하향링크에서 전송된 하이브리드 ARQ 패킷에 대한 응답(Acknowledgement)을 상향링크로 전송하는 방법과 이를 위한 송수신 장치에 관한 것이다. 이를 위하여 본 발명은 서로 다른 스크램블링 코드에 의하여 코드 축을 기준으로 다수로 분할되며, 하향링크 HARQ 패킷의 수신 성공 또는 오류에 대한 응답 신호가 탑재되는 ACK 채널과 다수의 ACK 채널을 코드 축으로 다중화하여 포함하는 ACK 채널 영역; HARQ 패킷의 오류 여부에 대한 응답을 기지국으로 전송할 때 함께 전송될 수 있는 채널 품질 정보인 피드백 정보를 탑재하는 피드백 채널 영역 및 이동 단말기에서 기지국으로 전송하는 데이터가 포함되는 데이터 영역을 이용하여, HARQ 패킷에 대한 응답 신호를 전송하는 방법과 이를 위한 이동 단말기 및 기지국을 제공한다. 본 발명에 의하면, 모든 무선 자원을 사용하여 응답 신호를 전송할 수 있으며, 이동 단말기의 숫자가 적은 경우에는 발생하는 간섭이 감소하게 됨에 따른 상향링크 신호의 신뢰성 향상 효과를 기대할 수 있다. 그리고, 응답을 전송하지 않을 이동 단말기의 숫자를 미리 예측하여 이동 단말기를 추가로 수용하도록 함으로써, 통계적 다중화 이득 효과를 기대할 수 있다. OFDMA, Hybrid ARQ, HARQ, 응답 신호, ARQ 응답, 상향링크 프레임
Abstract:
A method and an apparatus for estimating and compensating an uplink channel in an adaptive OFDMA system are provided to improve a channel estimation performance and a compensation performance by using a pilot tone and a data estimation value. A method for estimating and compensating an uplink channel in an adaptive OFDMA system includes the steps of: after removing data modulation from a received subcarrier by using a data estimation value instead of a pilot; compensates a channel for all subcarriers based on the removing result; estimating and compensating the channel by using a pilot tone variably and fixedly which is included in a data symbol according to the measured channel condition; using the pilot basically for estimating all channels in a synchronizing detection scheme; reducing power used in a real data symbol by using some of transmission power in the pilot; and using the pilot tone and the data estimation value in parallel by using channel information in the fixed data pilot tone.
Abstract:
An OFDMA apparatus having effect on increase in a channel capacity using a grouped orthogonal code signal value and a method thereof are provided to reduce a PAPR(Peak-to-Average Power Ratio) in the OFDMA and improve a performance efficiently by grouping a binary code having orthogonality. An OFDMA apparatus having effect on increase in a channel capacity using a grouped orthogonal code signal value includes the steps of: grouping a binary code having orthogonality in the same subchannel, and using the same in a channel capacity increase; reducing an interference of a similar neighboring subchannel; using a subchannel having a predetermined gap for a grouped orthogonal characteristic; re-using the same orthogonal code by grouping the binary code having the orthogonality and using the same orthogonal group at the subchannel having a gap which is not neighbored; reducing a PAPR in the OFDMA by grouping the orthogonal code; lessening MAI(Multiple Access Interface) by an MUD(Multi User Detection); and performing channel estimation by using a preamble.
Abstract:
응용 서버에게 이동 단말에 대한 착신 서비스를 제공하는 착신 서비스 제공 시스템이 개시된다. 착신 서비스 제공 시스템은 위치 서버와 페이징 제어기를 포함한다. 위치 서버는 휴지 상태의 이동 단말에 대하여 페이징 그룹 식별자를 통해 위치를 관리한다. 한편, 페이징 제어기는 응용 서버로부터 상기 이동 단말에 대한 착신 서비스를 요청받으면 상기 위치 서버에 상기 이동 단말의 상태와 상기 이동 단말의 위치를 조회한다. 그리고, 페이징 제어기는 상기 이동 단말의 상태가 상기 휴지 상태이면 상기 이동 단말이 속한 페이징 그룹에 해당하는 하나 이상의 페이징 제어기에 페이징 요청을 하여 상기 이동 단말이 네트워크 주소를 부여받도록 하며, 상기 네트워크 주소를 상기 응용 서버에 제공한다. 이로써, 착신 서비스 제공 시스템은 휴지 상태의 단말로부터 네트워크 주소에 해당하는 IP 주소를 회수하더라도, 휴지 상태의 단말에 대한 착신 서비스를 지원할 수 있다. 페이징, 휴대인터넷, WiBro, 802.16e, 착신 서비스, 휴지 상태
Abstract:
A method for controlling the amount of used resources in a wireless ad hoc network and a communication device using the method are provided to decide whether radio resources are exclusively used or the resources are less used unfairly, when each node transmits packets in the ad hoc network, and to adjust the amount of used resources according to the decided results, so that the nodes can fairly use the resources. A transmission node measures the amount of delivery data used for transmitting a packet(S410). The transmission node sets backoff time which determines the amount of used radio resources, according to the measured amount of the delivery data(S420-S470). The transmission node participates in a contention for transmitting a next packet by using the backoff time.
Abstract:
휴대 인터넷 시스템의 단말 장치에서 상향 데이터를 처리하는 방법에서, 분류기가 발생된 패킷을 등급별로 분류한다. 패킷이 분류된 후 큐 연산 함수의 정보가 순환 큐에 저장되고, 순환 큐에서 함수의 정보가 추출되면서 대기 큐에 큐잉 동작이 수행된다. 그리고 패킷 처리기가 대기 큐에 대기중인 패킷을 처리하여 송출한다. 휴대 인터넷, 단말, 상향, 순환큐, 타스크릿, 쓰레드