SDR Lattice-Reduction-Aided Detector

Communication techniques based on multiple-input multiple-output (MIMO) have been heavily exploited in the past decade, in order to obtain high capacity communication systems, aim to dealing with increasing spectrum scarcity scenarios. In this context, the semidefinite relaxation (SDR) signal detection strategy is promising due to its very near-optimal maximum-likelihood (ML) performance combined with polynomial complexity. However, the SDR detector has proved insufficient for systems with high order modulation, exactly where the recent pre-detection technique by lattice reduction (LR) has demonstrated excellent results in terms of performance-complexity. This paper investigates the performance-complexity tradeoff of the SDR detector under high order modulation in uncorrelated MIMO channels aided by lattice reduction technique applied in the pre-detection stage.