S-CDMA系统的串行捕获技术

Synchronization is a key technique of any communication system, especially in DS-CDMA（Direct Sequence Spread Spectrum-Code Division Multiple Access）system. The receive data will be totally noise if synchronization is lost. Synchronization technique in DS-CDMA system includes PN code acquisition, tracking, frame synchronization and carrier synchronization. PN code acquisition is the base of other synchronization processing. In this paper, we first describe DS-CDMA system, then summarize acquisition technique in DS-CDMA system, finally analyze several serial acquisition techniques in common use which are single-dwell serial acquisition, multi-dwell serial acquisition and non-continual acquisition in multi-path channel. There are 3 criterions to evaluate acquisition performance: average acquisition time, detection possibility and false possibility. This paper also analyzes the criterions for the acquisition techniques mentioned above.