A transmit diversity scheme for channels with intersymbol interference

Alamouti (see Journal of Selective Communications, vol.16, no.8, p.1451-58, 1998) proposes a two branch transmit diversity scheme for channels without intersymbol interference. With two transmit antennas and one receive antenna the scheme provides second order diversity. In this paper we derive a new method which handles the corresponding case when the channel suffers from intersymbol interference. The intersymbol interference can be caused by partial response modulation and/or delay spread in the propagation channel. As in Alamouti's paper, we show that with two transmit and one receive antenna, the same diversity can be achieved as with one transmit and two receive antennas. This new proposed scheme thus achieves full diversity for channels with intersymbol interference.