METHOD AND APPARATUS FOR UPLINK SYNCHRONIZATION IN WIRELESS COMMUNICATIONS

摘要

A method and system for uplink (UL) synchronization of an uplink transmission from a plurality of wireless transmit/receive units (WTRUs) to a Node-B in a code division multiple access (CDMA) system. A Node-B receives a transmission including a UL synchronization (SYNC_UL) sequence from a WTRU. A sampler samples the transmission at a sampling rate which is higher than a chip rate. The samples are down-sampled and the SYNC_UL sequence is detected at a lower rate. A first significant path location of the detected SYNC_UL sequence is determined, and based on the first significant path location, a final significant path location is determined. The final significant path location is quantized and UpPCH_POS is transmitted to the WTRU to adjust a UL transmission timing.