Channel Estimator Designs For Emerging 5G New Radio Cellular Systems

Abstract

The 5G new radio (NR) cellular system transmits demodulation reference signals (DM-RS) for a user to estimate precoded channel. The DM-RS can be optionally transmitted at various orthogonal frequency division multiplexing (OFDM) symbols. The 5G NR specifications does not explicitly tell how many DM-RS should be used, and needs to be decided by system designers. This work designs various channel estimators for the DM-RS, and based on the MSE performance, proposes an algorithm to decide the number of DM-RS required at a particular user speed.