Multi-User Detection (MUD) Scheme for Mitigating Co-Channel-Interference in Heterogeneous 5G Networks

It could be stated that to satisfy the ever-increasing capacity of LTE networks in terms of number of User Equipment (UE) and volume of traffic, Small-Cell architecture seems to be a competitive candidate. However, such systems will be Co Channel Interference (CCI) limited since densification of Base Stations (BS) will enforce reuse of the same frequencies in neighboring geographical regions, resulting in unacceptable levels of CCI. Previous researches has shown that, despite the higher signal power level available due to the reduced cell sizes, Single User Detection (SUD) techniques are still unable to sustain the required performance as a result of low Signal to Noise Interference Ratios of concern. Multi-User Detection (MUD) mechanisms are shown to be a promising solution to yield higher system capacity and acceptable levels of performance where multiple users communicate in the system simultaneously. The main aim of the current study is to highlight a MUD solution for mitigating the unacceptably high levels of CCI in Small Cell networks using the current spectrum allocated for the International Mobile Telecommunications (IMT) services by International Telecommunications Union (ITU). In addition, the proposed work focuses on OFDM framework where the existing Single-User system is extended to Multi-User one in order to improve system performance. Results have clearly depicted this improvement in system performance by the proposed MUD. Keywords: IMT-2020 Systems, 5G, Multi User Systems, Multi User Detection, Small-Cell, Co-Channel-Interference, Massive MIMO, Channel State Information.