Improved packet data performance for WCDMA using multi-antenna techniques

Multi-antenna systems have been proposed to improve data rates for third-generation networks, such as the highspeed downlink shared channel (HS-DSCH) packet-data mode in the WCDMA system. We consider the impact of incorporating two multiple transmit antenna systems into HS-DSCH. The first uses transmit diversity with channel knowledge at the transmitter together with a single receive antenna, while the second is an open-loop scheme with multiple transmit and receive antennas. In dispersive propagation environments, multiple access and intersymbol interference, resulting from multicode and multi-antenna transmissions, must be handled appropriately to avoid limiting overall performance. We show, through system simulations, that improved system and user throughputs can be obtained in realistic channel conditions due to the combined effects of channel and multiuser diversity.