Effects of inter cell interference in mixed CSIT down link channel

Abstract

HISTORY In cellular scenario, a multiple-antenna base station (BS) can serve multiple User Equipments (UEs) within same resources by engaging capable MIMO strategies. Though sophisticated multi-user techniques cancel inter-UE interferences, they necessitate up to date Channel State Information on Transmitter (CSIT) side. Different generations of UEs with different feedback mechanisms and the same generation of UEs with different mobility levels lead to the mixed CSIT scenario where BS has complete CSIT of some UEs and outdated or no CSIT of other UEs. This situation leads to inter- UE interferences. In modern cellular networks, there is another dominant source of interference that emerges from the tighter frequency reuse factor and the reduced cell sizes. This type of interference termed as intercell interference severely affects the performance of the system, especially of the cell-edge UEs. STUDY Inspired by its importance, this study explores this scenario of over-dimensioned interference under mixed CSIT scenario for LTE, where the UE faces both inter-UE and inter-cell interferences. We have shown that the performance of standard type 3i MMSE receivers, which are candidate receivers for 3GPP LTE, is severely degraded in this scenario. We recommend the engagement of recently advised low complexity interference-aware receivers in this scenario and show that these receivers have the capability to adapt to these scenarios of over-dimensioned interference, thereby outperforming the candidate receivers of 3GPP LTE. FUTURE REQUIREMENTS Continue the study to further devise methodologies for ideal frequency resources usage considering the viable requirements for genuine execution in reality.