Error Performance of RIS-Assisted NOMA Networks with Imperfect Channel State Information

This paper investigates the impact of imperfect channel state information (ipCSI) on the performance of RIS-assisted NOMA vehicular networks while considering the effect of imperfect successive interference cancellation (ipSIC). Moreover, we present novel closed-form pairwise error probability (PEP) expressions with arbitrary L users. The PEP is used to evaluate the union bound on the bit error rate of NOMA users. Finally, the analysis is supported by numerical and Monte Carlo simulation results. We show that the impact of ipCSI with ipSIC on each user’s error rate performance is great at the high P
s
. We also confirm that the error rate performance of the system decreases with the increase of RUs.