Signals With Sparse Mutual Interference for Sounding Massive MIMO Channels

Abstract

In this paper, we propose a set of new sounding reference signals (SRSs) for time-division duplexing (TDD) massive MIMO systems with channel aging. It is analytically shown that the proposed set of SRSs exhibit superior zero correlation zone (ZCZ) property, which guarantees sparse and marginal interference between each other. Therefore, all SRSs in the set can be transmitted concurrently in a cell with a short SRS period per user to alleviate the channel aging effect. We also investigate the detailed SRS construction to achieve low peak-to-average power ratios (PAPRs). Finally, simulation results are provided to show that the proposed SRSs result in significantly larger downlink throughput than the existing 5G New Radio SRSs.