DMRS Design and Evaluation for 3GPP 5G New Radio in a High Speed Train Scenario

This paper proposes demodulation reference signal (DMRS) designs for the 3GPP 5G New Radio (NR) high speed train scenario. Considering a carrier frequency of 30 GHz, each DMRS design specifies the density and location of the DMRS symbols in the frequency-and time-domains. The proposed DMRS design sets are intended to support accurate channel estimation in a very high mobility environment up to 500 km/h while limiting DMRS overhead to an acceptable level. Throughout extensive link-level simulations, it is shown that satisfactory block error rate (BLER) and spectrum efficiency performances can be achieved by using the proposed DMRS design sets even with severe Doppler shift/spread.