| Title |
An Analysis of Sidelink Throughput in the 5G NR based Cellular V2X Systems |
| DOI |
https://doi.org/10.5573/ieie.2021.58.7.14 |
| Keywords |
V2X; 5G NR; Sidelink; Throughput; DM-RS |
| Abstract |
C-V2X (cellular V2X) technology based on 5G NR (New Radio) is attracting attention as a core technology for autonomous driving or advanced driving services. In order to achieve autonomous driving beyond simple safe driving, it is necessary to ensure stable data throughput at ultra-low latency and high relative speeds. When the relative speed between vehicles is high, since the characteristics of the channel change rapidly, reliable communication in a time varying frequency selective fading environment must be achieved. In order to cope with the time variability of the channel, in the LTE or 5G NR standards, a demodulation reference signal (DM-RS) is transmitted at the transmitting side to be used for channel estimation. In the 5G NR sidelink, 2 to 4 DM-RS symbols can be variably applied per slot. In addition, in 5G NR, variable sub-carrier spacing (SCS) is supported, and accordingly, the slot length can be variously selected, and as a result, the density of the DM-RS symbol on the time axis can be changed. In this paper, the performance of the system was evaluated in terms of data throughput while changing the density of DM-RS density on the time axis by setting the SCS and the number of DM-RS symbols per slot for 5G NR sidelink communication. Data throughput was measured while changing the system configuration for SCS and DM-RS under various Doppler frequencies and delay spread conditions of channels. |