A Channel Prediction Scheme for Closed Loop Transmit Diversity in High Speed Downlink Packet Access

A closed loop transmit diversity (CLTD) scheme is specified in high speed downlink packet access (HSDPA) to provide high data rates by obtaining a diversity gain in mobile radio channels. However, if mobile channel varies rapidly, i.e. mobile speed becomes faster, it is hard to obtain a diversity gain because of the feedback delay of channel quality information from UEs to NodeB. To mitigate such a performance degradation in the closed loop transmit diversity, we propose a channel prediction scheme. This proposed scheme improves the performance of the closed loop transmit diversity through channel prediction using a channel transition history