Interference Alignment Schemes Using Latin Square for K <inline-formula> <tex-math notation="LaTeX">$\times$ </tex-math></inline-formula> 3 MIMO X Channel

Abstract

In this paper, we study an interference alignment (IA) scheme with finite time extension and beamformer selection method with low computational complexity for X channel. An IA scheme with a chain structure by the Latin square is proposed for $K \times 3$ multiple-input multiple-output X channel. Since the proposed scheme can have a larger set of possible beamformers than the conventional schemes, its performance is improved by efficient beamformer selection for a given channel realization. Also, we propose a condition number-based beamformer selection method with low computational complexity and its performance improvement is numerically verified.

Keywords

• Beamforming
• degrees of freedom (DoF)
• interference alignment (IA)
• latin square
• multiple-input multiple-output (MIMO)
• X channel