Uplink training for pilot decontamination in a multiceli massive MIMO system

In this paper, we investigate pilot contamination in a multiceli massive multiple-input multiple-output (MIMO) system, in which the estimated channel state information (CSI) suffers a crucial difference from the real CSI. Pilot contamination is an obstacle to the achievable rate for users. We propose an uplink training strategy to limit the effect of intercell pilot contamination on channel estimation with low complexity. As a result, the downlink data rate through the reciprocity channels is significantly improved, which is verified by numerical results.