Performance Evaluation of Soft FFR Scheme in RIS-Aided Ultra Dense Femto-Macrocellular Network

Ultra Dense Network (UDN) and Reconfigurable Intelligent Surface (RIS) are known as latest technologies that can enhance system capacity and performance. Deployment of RIS in UDN can overcome the signal blockages that is common in urban areas where UDN applied. However, due to dense deployed small cells, i.e. femtocell in macrocellular network, co-channel interference in UDN faces challenging problem. Applying RIS in UDN can encounter the interference problems more challenging. This paper applies soft FFR scheme in RIS-aided UDN cellular network to investigate its effects in mitigating interference problems in RIS-aided UDN cellular network. Simulation experiment has been carried to evaluate the performance of such RIS-aided UDN network. Three parameters are used to evaluate the performance of network under study, namely Signal-to- Interference plus Noise Ratio (SINR), throughput and Bit Error Rate (BER). The outcomes of the simulation for the network with soft FFR are compared to the network without FFR scheme, referred to as baseline system. The simulation results show that the SINR of femtocell for the network with soft FFR scheme increases 3.07 dB, throughput increases 9.99 Mbps and BER decreases from 2.96 x 10–<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> to 5.73 X 10-<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sup>• The system with soft FFR scheme outperforms the baseline system and soft FFR is promising to reduce the interference effects in RIS-aided UDN network.