摘要: Space-time transmit diversity is mainly designed to combat channel fading in downlink transmission by combining the channel coding and array diversity technique, thus expands communication system capacity and attains diversity gai... 展开 Space-time transmit diversity is mainly designed to combat channel fading in downlink transmission by combining the channel coding and array diversity technique, thus expands communication system capacity and attains diversity gain and coding gain. Most modellings on space-time transmit diversity are based on the assumption that there is single-path arriving at the receive antenna from a transmit antenna. However, there are multipaths to arrive at the receive antenna from a transmit antenna in practice. Conventional space-time transmit diversity scheme where the same spread code is used in transmit antennas has some disadvantages in the practical system and its performance undesirable in multipath Channel. A novel space-time transmit diversity scheme where orthogonal spread codes are used respectively at the transmit antennas is presented to solve this problem. Simulation results reveal that the space-time transmit diversity scheme presented in this paper have much better performance than conventional transmit diversity in multipath channel. We also find that this space-time transmit diversity scheme has better performance as with the increasing of multipath number. 收起