Statistical analysis of user-pairing algorithms in virtual MIMO systems

In this paper a novel algorithm for user-pairing is proposed for virtual multiple-input multiple-output (V-MIMO) systems. Channel orthogonality is utilized to derive an expression for the output SNR (OSNR) in a V-MIMO system. We also show that the V-MIMO OSNR almost surely converges to the OSNR of a single input multiple output transmission as number of receive antennas approach infinity. Applying the statistical properties of orthogonality to independent and identically distributed wireless channels, system performance for the proposed pairing algorithm is evaluated in terms of joint capacity, OSNR loss, throughput fairness, and computational complexity. Numerical results show that the proposed orthogonal pairing algorithm outperforms conventional pairing methods that are oriented to maximize joint capacity.