Linear precoding under iterative processing for multiple antenna channels

We propose a universal linear precoder for bit-interleaved coded QAM modulations transmitted over frequency non-selective multiple antenna channels. The precoder is based on cyclotomic multi-dimensional rotations and does not require the knowledge of the channel matrix at the transmitter side. The preceding performance analysis is made via the genie method by assuming a receiver with iterative APP detection. We also describe a new singleton bound on the diversity order that takes into account the time-spreading factor of the precoder. This new bound is indispensable to select the precoder size yielding the maximum diversity order while minimizing the detector´s complexity.