Per-tone chip equalization for space-time block coded single-carrier block transmission DS-CDMA downlink

In this paper, we extend space-time block coding techniques, originally proposed for point-to-point communication links, to point-to-multipoint communication links. In specific, we combine space-time block coding with single-carrier block transmission DS-CDMA for downlink multi-user MIMO communications. Moreover, we propose a pilot-trained space-time chip equalizer that acts on a per-tone basis in the frequency-domain. With M_t transmit antennas at the base station, M_r receive antennas at the mobile station and the order of the multi-path channel, it comes close to extracting the full diversity of order M_t · M_r · (L + 1) in reduced as well as full load settings.