Lattice-Reduction-Aided Preprocessing for Physical-Layer Security

This work considers physical-layer security for wireless MIMO communication using different preprocessing approaches. We evaluate two optimization criteria: preprocessing according to the error ratio of the legitimate receiver, which does not take the eavesdropper into account, and preprocessing according to the secrecy rate. Linear preequalization and lattice-reduction-aided preequalization are well-known techniques for the first setting. We propose a novel approach that combines lattice reduction with preprocessing according to the secrecy rate. Numerical simulations are conducted, and the results are used to compare the presented preprocessing variants according to the error ratio of the legitimate receiver and the achieved secrecy rates.