Improved Design for Slot Synchronization in WCDMA Cell Search

Among the 3G cellular systems being considered, IS-2000 and Wideband Code-Division-Multiple-Access (WCDMA) are both based on direct-sequence code-division multiple-access (DS-CDMA) technology. In these systems, spreading codes are used to differentiate physical channels from the same transmitter, and scrambling codes are used to differentiate transmitters. A mobile station (MS) needs to code and time synchronized to the scrambling code used by the serving cell before any communications with the base station can take place. The synchronization process in W-CDMA can thus be viewed as the five stage process of 1) slot synchronization, 2) frame synchronization and scrambling code group identification, 3) scrambling code identification, 4) frequency acquisition, and 5) cell identification. This paper suggests the improved design of matched filter, used in first stage of WCDMA synchronization.