Soumana Hamadou, A.N.; wa Maina, C.; Soidridine, M.M. Cross-Tier Interference Mitigation for RIS-Assisted Heterogeneous Networks. Technologies2023, 11, 73.
Soumana Hamadou, A.N.; wa Maina, C.; Soidridine, M.M. Cross-Tier Interference Mitigation for RIS-Assisted Heterogeneous Networks. Technologies 2023, 11, 73.
Soumana Hamadou, A.N.; wa Maina, C.; Soidridine, M.M. Cross-Tier Interference Mitigation for RIS-Assisted Heterogeneous Networks. Technologies2023, 11, 73.
Soumana Hamadou, A.N.; wa Maina, C.; Soidridine, M.M. Cross-Tier Interference Mitigation for RIS-Assisted Heterogeneous Networks. Technologies 2023, 11, 73.
Abstract
This study investigates the applications of reconfigurable intelligent surfaces (RIS) in heterogeneous downlink networks (HetNet). Due to the network densification, the small cell base station (SBS) interferes with the macrocell users (MUE). In this paper, we utilize RIS to mitigate cross-tier interference in an HetNet via directional beamforming by adjusting the phase shift of the RIS. We consider an RIS-assisted HetNet consisting of multiple SBS nodes and MUEs that utilize both direct paths and reflected paths. Therefore, the aim of this study is to maximize the sum rate of all MUEs by jointly optimizing the transmit beamforming of the macrocell base station (MBS) and the phase shift of the RIS. An efficient RIS reflecting coefficients-based optimization (RCO) is proposed based on a successive convex approximation approach. Simulation results are provided to show the effectiveness of the proposed scheme in terms of its sum rate in comparison with the scheme HetNet without RIS and the scheme HetNet with RIS but with random phase shifts.
Keywords
RIS; HetNet; Spectral Efficiency; Cross-tier Interference; Optimization; MIMO
Subject
Engineering, Telecommunications
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
