Design of Space-Time Multi-Block Codes for MIMO Systems with Linear MMSE Receivers

We consider a multi-input multi-output (MIMO) communication system equipped with a linear minimum mean-square error (MMSE) receiver. We design a full-rate linear space-time block code (STBC) for blocks of data that span several realizations of a block-static fading channel to achieve high diversity gain. The proposed code structures are necessary and sufficient to minimize the detection error probability. They also enable the detection computations to be partitioned into separate blocks such that the normalized complexity is reduced to little more than that for a single block. The additional complexity grows only linearly with $L$, the number of blocks for which the code design covers. Analysis shows that the diversity gain achieved by the code also grows linearly with $L$. This is confirmed by simulation results.