Space-time-coded OFDM-transmission with spatial interpolation in the presence of severe doppler spread

Space-time codes are a means to gain from spatial diversity with a suitable receiver. Among the large family of space-time codes the class of orthogonal space-time block codes offers the prospect of harvesting the possible diversity gains by low-complexity linear detection, which is equivalent to maximum-likelihood detection. A prominent representative of this class is the Alamouti code. Moreover, accompanied by OFDM frequency-selectivity is seamlessly coped with. Usually, the prerequisite of time-invariant channel conditions must be fulfilled to uphold the orthogonality of the codewords. This constraint is violated in high-mobility environments, where the channel coefficients might change during a space-time codeword. Here, a receiver-side uniform linear array can be employed to generate seemingly time-invariant channels. In this paper, we present an Alamouti space-time coded OFDM system under high Doppler influence assisted by an uniform linear antenna array to compensate for the rapidly fading channel conditions.