  Massive multiple-input multiple-output (MIMO) is a critical technology for
future fifth-generation (5G) systems. Reduced pilot contamination (PC) enhanced
system performance, and reduced inter-cell interference and improved channel
estimation. However, because the pilot sequence transmitted by users in a
single cell to neighboring cells is not orthogonal, massive MIMO systems are
still constrained. We propose channel evaluation using orthogonal pilot reuse
sequences (PRS) and zero forced (ZF) pre-coding techniques to eliminate channel
quality in end users with poor channel quality based on channel evaluation,
large-scale shutdown evaluation, and analysis of maximum transmission
efficiency. We derived the lower bounds on the downlink data rate (DR) and
signal-to-interference noise ratio (SINR) that can be achieved based on PRS
assignment to a group of users where the number of antenna elements mitigated
the interference when the number of antennas reaches infinity. The channel
coherence interval limitation, the orthogonal PRS cannot be allocated to all
UEs in each cell. The short coherence intervals able to reduce the PC and
improve the quality of channel. The results of the modelling showed that higher
DR can be achieved due to better channel evaluation and lower loss.
