Pilot Contamination Reduction Scheme in Massive MIMO Multi - cell TDD Systems ⋆

In this paper we consider massive MIMO Multi-cell TDD systems. In order to eliminate the effect of pilot contamination, a new scheme is proposed. In the same cell all transmitted signals from base station or user are multiplied same precoding sequences. The precoding sequences are orthogonal for different cell. The received signals at base station or terminals are multiplied the conjugate transpose of corresponding precoding sequences. Using the new scheme, the effect of pilot contamination is eliminated and SIR grows indefinitely for an unlimited number of base station antennas. When the interference of adjacent cell is very serious and the number of base station antennas is very large, the numerical results show that the new scheme provides noticeable improvement compared with MRC, LP, TSP scheme. Numerical results verify the effectiveness of the new scheme.