Effects of lattice reordering on Schnorr-Euchner decoding algorithms for MIMO systems

Schnorr-Euchner (SE) decoding algorithm for MIMO sys tems has been shown to approach the performance of Maximum-likelihood decoder with low complexity. There are two kinds of SE decoder, sequential SE and K-best SE. The lattice reordering, as the preprocessing of the SE de coder, is divided into four modes in this paper, according to post-detection signal-to-noise ratio (SNR) and channel noise level. The numerical complexity and stability of each mode are analyzed. Moreover, the effects of the four pre processing modes are analyzed on the sequential SE and the K-best SE, respectively. Simulation results show that the complexity of the sequential SE and the K-best SE can be reduced efficiently, if the preprocessing mode is chosen suitably