OFCDM 시스템에서 PCSSCG를 이용한 셀 탐색에 관한 연구 = A Study on a Cell search Using PCSSCG in Broadband OFCDM Systems

국문 초록 (Abstract)

비동기 OFCDM 시스템 환경에서 초기 동기을 위한 셀 탐색 방법이 다음과 같이 3단계 방법으로 수행된다. 셀 탐색 1단계에서 보호구간의 상관을 이용한 심볼동기 즉, FFT 윈도우 타이밍 추정과 탐색 2 단계는 주파수영역에서 CSSC(Cell Specific Scrambling Code) 위상 천이성질을 이용한 CPICH(Common Pilot Channel)의 상관을 획득함으로써 프레임 타이밍 및 CSSC그룹을 검출하고 마지막으로 탐색 3 단계에서 그룹 안에 속한 CSSC 위상 즉, 최적의 CSSC를 얻게 된다. 본 논문에서는 탐색 2단계에서 기존의 CPICH만을 이용한 셀 탐색방법을 변형한 PCSSCG(partial cell specific scrambling code group)를 이용하여 성능을 거의 같은 수준으로 유지하면서 이동국의 복잡도를 줄이는 셀 탐색 방법을 제안한다. 제안된 방법은 모의실험을 통하여 기존의 방법과 비교 검증하였다.

다국어 초록 (Multilingual Abstract)

In the asynchrous OFCDM(Orthogonal Frequency and Code Division Multiplexing) system, a three-step cell search algorithm is performed for the initial synchronization in the following three steps: OFCDM symbol timing, i.e., Fast Fourier Transform(FFT) window timing is estimated employing guard interval (GI) correlation in the first step, then the frame timing and CSSC (Cell Specific Scrambling Code) group is detected by taking the correlation of the CPICH(Common Pilot Channel) based on the property yeilded by shifting the CSSC phase in the frequency domain. Finally, the CSSC phase within the group is identified in the third step. This paper proposes a modification code(PCSSCG:Patial Cell Specific Scrambling Code Group) of the conventional CPICH based cell search algorithm in the second step which offers MS(Mobile Station) complexity reductions with the nearly same performance. The proposed method is to be compared and verified through the computer simulation.

참고문헌 (Reference)

1 H. Atarashi, "Variable spreading factor-orthogonal frequency and code division multiplexing (VSF-OFCDM) for broadband packet wireless access" e86-b (e86-b): 2003

2 M. Tanno, "Three-step fast cell search algorithm utilizing common pilot channel for OFCDM broadband packet wireless access" 3,1575 : 2002

3 Y. Ishii, "Three-step cell search algorithm employing synchronization and common pilot channels for OFCDM broadband wireless access" e85-b (e85-b): 2002

4 M. Tanno, "Fast cell search algorithm for system with coexisting cellular and hot-spot cells suitable for OFCDM forward link broadband wireless access" 1,133 : 2003

5 Dae Yong Kim, "A Suitable Cell Search Algorithm Using Separated I/Q Channel Cell Sepcific Scrambling Codes for systems with Coexisiting Cellular and Hot-Spot Cells in Broadband OFCDM Systems" 2004