Pilot design and allocation for multi-cell massive MIMO systems with two-tier receiving

This paper investigates pilot design and allocation in multi-cell massive multiple-input multiple-output systems with two-tier receiving. Based on the analysis of the signal-to-interference-plus-noise ratio (SINR), the discrete Fourier transform vectors are employed in designing pilots with various correlation values, and the pilots are allocated to the cells in a greedy way with the object of maximizing the sum rate upper bound.