Abstract:
본 발명은 적어도 두 개 이상의 송신 안테나들을 사용하는 통신 시스템에 관한 것으로서, 신호 검출 방법에 있어서, 변조 방식에 상응하는 개수의 심볼들 중 최소 가지 메트릭 값에 상응하는 심볼을 선택하는 과정과, 상기 선택된 심볼에서 최소 가지 메트릭 값에 상응하는 심볼을 선택하는 과정을 송신 안테나 수보다 한번 작은 수만큼 확장하여 후보 심볼을 결정하는 과정과, 상기 후보 심볼의 누적 가지 메트릭 값을 기준값으로 설정하여 상기 기준값 이상의 누적 가지 메트릭 값을 가지는 심볼을 제거하여 마지막 단계까지 제거되지 않고 선택된 경로들 중 최소 누적 가지 메트릭 값을 가지는 경로에 상응하는 심볼을 최종 수신 심볼로 선택하는 과정을 포함한다. QRD-M 알고리즘, 트리 서칭, 변조 방식, 가지 메트릭 값
Abstract:
A multiple carrier based multiple antenna system and an OFDM transmitting method using the same are provided to improve transmission efficiency by applying a SFBC(Space Frequency Block Code) method and a PCC preprocess method using an LCF(Linear Complex Field) code in a multiple antenna environment. A multiple carrier based transmission antenna system converts a signal transmitted by using a plurality of antennas in series or parallel, and encodes the converted signal by a precoding encoder(130). A serial/parallel converter(120) converts the modulated data symbol from series to parallel and transmits the converted data symbol to the precoding encoder. The precoding encoder transmits a coded signal in each antenna and the signal with an opposite phase to the coded signal by using different subcarriers and sets the sub carrier of the coded signal in at least one antenna identical to the subcarrier of the coded signal with the opposite phase of other antennas. The precoding decoder processes the received signal by applying an ML(Maximum Likelihood) method.
Abstract:
An apparatus and a method for transmitting and receiving a signal in a MIMO(Multiple Input Multiple Output) broadband wireless communication system are provided to increase the gain of diversity in an MIMO broadband wireless communication system. A transmitting apparatus in an MIMO broadband wireless communication system comprises: a first encoder(240-1) which Alamouti-encodes complex symbols of Nc/n number, which are to be transmitted through a pair of first antennas, repeatedly n times; a second encoder(240-2) which Alamouti-encodes complex symbols of Nc/n number, which are to be transmitted through a pair of second antennas, repeatedly n times; and plural RF(Radio Frequency) transmitters(260-1 to 260-4) which transmits Alamouti-encoded complex symbols which are mapped on subcarrier of Nc number.
Abstract:
A device for improving IDD(Iterative Detection and Decoding) reception performance in a multi-antenna system and a method thereof are provided to generate an LLR(Long Likelihood Ratio) by performing sorted QR decomposition in the multi-antenna system, thereby reducing complexity without deterioration of performance of a receiving device. A detector(301) estimates a transmission signal by using a signal received through an antenna. An LLR generator(305) generates an LLR by conducting sorted QR decomposition for a signal fed back from a decoder(309) or the transmission signal estimated in the detector(301). A deinterleaver(307) performs a deinterleaving process for the generated LLR, and provides the deinterleaved LLR to the decoder(309).