Pilot contamination mitigation in TDD massive MIMO systems

Abstract

Massive multiple-input multiple-output (MIMO) systems are expected to achieve significant gains in both energy and spectral efficiency compared to conventional MIMO systems. However, these promising gains are limited by the impact of pilot contamination in TDD multicell massive MIMO. In this paper we address how to counter the problem of pilot contamination and propose an algorithm for pilot sequences allocation. The proposed algorithm takes advantage of the multiplicity of pilot sequences over the number of users in each cell to reduce the effect of pilot contamination. Our results show that the algorithm can significantly improve the spectral efficiency compared to the conventional pilot allocation algorithm.