Abstract:
본 발명은 OFDM 셀룰러 시스템에서의 동기 채널의 전송 방법 및 장치에 관한 것으로, 복수의 주 동기 채널 신호와 부 동기 채널 신호를 포함하는 동기 채널 신호를 다중화하고 상기 동기 채널 신호를 프리코딩할 때 사용할 프리코딩 벡터를 선택한 후, 상기 동기 채널 신호와 상기 프리코딩 벡터를 곱한다. 동기 채널 전송, OFDM 셀룰러 시스템, 빔형성
Abstract:
본 발명은 OFDM 셀룰러 시스템에서의 셀 고유번호 개수 증가에 적합한 동기신호 전송방법 및 동기채널 프레임 구조에 관한 것으로, 무선통신 시스템에서의 순방향 동기신호 전송방법에 있어서, 복수 개의 심볼로 구성되는 프레임을 생성하는 단계와 상기 프레임을 순방향 링크를 통해 전송하는 단계를 포함하고, 상기 프레임은 동일한 시간의 심볼 내의 주파수에 따라 구분된 주동기채널(P-SCH) 및 부동기채널(S-SCH)을 포함하며, 상기 주동기채널과 상기 부동기채널을 이용하여 검출된 코드번호의 패턴에 의해 셀 식별자를 특정하는 것을 특징으로 하며, 일정 시간 범위에서 부동기채널 신호의 반복 패턴이 증가하게 함으로써 단말기의 주파수 오차 추정 성능을 향상시키는 효과가 있다. 주동기채널(P-SCH), 부동기채널(S-SCH), 동기신호, 순방향 링크 프레임
Abstract:
본 발명은 직교 주파수 분할 다중 접속(Orthogonal Frequency Division Multiple Access: 이하, OFDMA) 시스템에서의 하향링크 스케줄링 정보 송/수신 방법 및 장치에 관한 것으로, 이 송신 방법은 OFDMA 시스템의 하향 링크 자원으로 구성된 자원블록들 중에서, 적어도 하나의 자원블록을 각 단말에 할당하는 할당단계; 상기 각 단말에 대해, 상기 할당된 자원블록 중에서 소정의 조건에 따라 자원블록을 선택하는 선택단계; 상기 각 단말에 대해, 상기 단말의 자원할당정보 및 상기 단말을 식별하기 위한 식별정보를 포함하는 스케줄링 정보를 생성하는 생성단계; 및 상기 각 단말에 대해, 선택된 자원블록을 이용하여 상기 단말의 스케줄링 정보를 전송하는 전송단계를 포함한다. 본 발명에 따르면, 스케줄링의 자유도를 줄이지 않으면서 스케줄링 정보의 전송에 사용되는 하향 링크 자원의 량을 줄일 수 있다. OFDM, OFDMA, 하향링크 제어정보, 스케줄링 정보, 자원할당 정보, 개별적 코딩, 그룹별 코딩, 비트맵
Abstract:
프리앰블 생성 장치는 주파수 영역에서 시퀀스를 생성하고, 시퀀스를 푸리에 역변환하여 시간 영역에서 푸리에 역변환 신호를 생성하며, 푸리에 역변환 신호를 인터폴레이션하여 프리앰블을 생성한다. 이를 통해 큰 크기의 DFT/IDFT를 사용하지 않고 프리앰블을 생성할 수 있다. 프리앰블, 채널, 응답
Abstract:
A method for generating a downlink frame and a method for searching a cell are provided to improve efficiency of searching the cell by receiving the downlink frame and to level interference between sectors by scrambling a short sequence to a scrambling sequence. A first shot sequence and a second short sequence indicating the cell group information are generated. A first scrambling sequence and a second scrambling sequence decided by a first synchronization sequence are generated(S510). A third scrambling sequence determined by the first shot sequence is generated. The first shot sequence is scrambled to the first scrambling sequence. The second short sequence is scrambled to the second scrambling sequence and the third scrambling sequence(S520). A second synchronization signal including the scrambled first shot sequence and the scrambled second short sequence is mapped in the frequency domain(S530). An OFDM transmission unit receives the frame of the downlink signal and transmits the frame through the transmission antenna(S540).
Abstract:
A method for generating a downlink frame and a method for searching a cell are provided to improve cell searching performance by reducing interference between sectors by scrambling two sequences with different scrambling codes. A sequence generator generates a plurality of sequences, and a plurality of scrambling sequences and transmits the sequences to the synchronization signal generator(S410). A synchronization signal generator generates a second synchronization signal by using the plurality of sequences received from the sequence generator, and the plurality of scrambling sequences(S420). A frequency mapping device maps the data to be transmitted by using the synchronization signal generated in the synchronization signal generator and transmission traffic data as the time and frequency domains and generates the frame of the downlink signal(S430). The OFDM transmitter receives the frame of the downlink signal and transmits the frame through a transmission antenna(S440).
Abstract:
A method for transmitting signal in wireless communication system using time and frequency domain at the same time is provided to efficiently reduce interference between cells by using a code hopping method. A method for transmitting signal in wireless communication system using time and frequency domain at the same time comprises the following steps: a step for assigning an identical frequency domain discrimination sequence and a unlike time domain discrimination sequence into a plurality of terminals by a resource index according to the first slot in a first slot; and a step for assigning a unlike frequency domain discrimination sequence and a unlike time domain discrimination sequence into a plurality of terminals by a resource index according to the second slot in a second slot.
Abstract:
A method for transmitting ACK/NACK though frequency division multiplexing for transmitting ACK/NACK bit is provided to improve efficiency of down link wireless resource by suggesting an efficient ACK/NACK channel transmitting method. A method for transmitting ACK/NACK though frequency division multiplexing for transmitting ACK/NACK bit supports HARQ(Hybrid Automatic Repeat request) in a wireless communications system supporting multi-user MIMO(Multi Input Multi Output). Mobile stations using an identical upward link resource performs a frequency division multiplexing. Mobile stations using a different upward link each other transmits ACK(ACKnowledgement)/NACK(Negative ACKnowledgement) multiplexed by a code division multiplexing or a frequency division multiplexing.
Abstract:
An apparatus and a method for compensating the frequency offset in a wireless communication system are provided to perform the frequency offset compensation easily as having good performance, by having one compensation coefficient per sub carrier in a frequency domain. According to an apparatus for compensating frequency offset in a wireless communication system, a Fast Fourier Transform part(130) transforms a time domain signal into a frequency domain signal through FFT(Fast Fourier Transform). A frequency offset and channel estimation part(140) extracts a reference signal from the frequency domain signal, and then generates a frequency offset compensation coefficient and estimates a channel. A channel equalizing part(150) compensates frequency offset and performs channel equalization on the basis of the frequency offset compensation coefficient and the channel estimation result of the channel estimation part.
Abstract:
A method and an apparatus for transmitting a downlink pilot signal in a mobile communication system are provided to enable a BS(Base Station) to change a scrambling code allocated to each sector and change an interference sector in each sub frame and randomize interference between the sectors, thereby preventing the continuous deterioration of channel estimation capability generated by the multiple path of the interference sector. A method for transmitting a downlink pilot signal in a mobile communication system comprises the following steps of: generating and transmitting a first downlink pilot signal corresponding to a first sector; generating and transmitting a second downlink pilot signal which corresponds to a second sector and is different from the first downlink pilot signal; and differently generating the first downlink pilot signal and the second downlink pilot signal in each sub frame.