Average Rate and Error Probability Analysis in Short Packet Communications Over RIS-Aided URLLC Systems

In this paper, the average achievable rate and error probability of a reconfigurable intelligent surface (RIS) aided systems is investigated for finite blocklength (FBL) regime. The performance loss due to presence phase errors arising from limited quantization levels as well hardware impairments at RIS elements also discussed. First, composite channel containing direct path plus product reflected channels through characterized. Then, distribution received signal-to-noise ratio (SNR) matched Gamma random variable whose parameters depend on total number elements, channels' loss. Next, by considering FBL regime, expression are identified corresponding elaborated based proposed SNR distribution. Furthermore, impact either or numerical results show that Monte Carlo simulations conform sufficiently large elements. addition, system reliability indicated tightness increases when leveraged particularly only exists. This highlights advantages RIS-aided communications ultra-reliable low-latency systems. difference between Shannon capacity in regime Additionally, required achieve desired will be significantly reduced shifts performed without error.