Lattice decoding for cooperative communications using the segment LLL algorithm

Lattice decoding is now an established approach to reduced-complexity decoding in digital communications. How- ever, it is still not fast enough in space-time coded cooperative communications, since the dimension of the equivalent MIMO model can be quite high here. To lighten the burden on decoding, this paper presents novel lattice decoding based on segment LLL reduction. In particular, we propose complex-valued segment LLL reduction resulting in reduced decoding complexity, and prove that it can achieve the optimal diversity-multiplexing tradeoff (DMT). Simulation results demonstrate that near-LLL aided decoding performance is achieved by a moderate number of segments.