Capacity and Interference Analysis for Heterogeneous Mobile Communication Networks

Abstract

Increasing demand for data traffic in cellular networks has become one of the characteristics of our new lives. However, the spectral efficiency is approaching its theoretical limits. Therefore, further improvements in network capacity require increasing the density of networks. On the other hand, in already existing dense node cellular networks, the gain of cell splitting is extremely limited because of inter-cell interference. Moreover, the high cost of base stations discourages this approach. Therefore, in response to the capacity challenge, the industry is developing a new solution to accommodate the increasing capacity demand. In 4G, LTE-advanced has adopted heterogeneous networks to be the main solution to capacity demand by adding small cells (Pico cells, Femtocells) underlay the large existing cells (micro cells). The novelty of this work is in the integration of RIS with CoMP HetNets under stochastic geometry modeling for single and multi-RIS interference scenarios. Simulation results show that RIS-assisted coordination improves SINR at the cell edge by about 3–4 dB compared to the uncoordinated case. Also, the sum rate increased by around 10–15 bit/s/Hz, in the case without RIS, to nearly 75–85 bit/s/Hz with RIS. To obtain the same BER, the required SNR can be reduced by 5–8 dB by increasing RIS elements.