An Efficient Inter-Cell Interference Coordination Scheme in Heterogeneous Cellular Networks

Abstract

As a mainstream technology in the 4G TDD (Time Division Duplex) systems, TD-LTE (Long Term Evolution) introduces heterogeneous network topology, utilizing a diverse set of base stations, to improve spectral efficiency per unit area. In heterogeneous network deployment comprised of macrocell and picocell, inter-cell interference coordination (ICIC) is very important to significantly improve the system and cell-edge throughput. Moreover, variety of complex situation of inter-cell interference (ICI) occurs in heterogeneous TDD LTE cellular networks due to different downlink/uplink (DL/UL) sub-frame configurations of macrocell and picocell. Therefore, this paper proposes an efficient ICIC scheme consisting of four sub-schemes according to relevant interference scenarios based on different sub-frame configurations. The scheme first analyzes interference level and finds out strong interference for each scenario. The basic idea of ICIC is that only primary interfering sources of each scenario avoid using the same frequency resource occupied by interfered victim, and other interfering sources can reuse frequency resource. Numerical results show that our proposed ICIC scheme can not only improve performance of whole region including macrocell area and picocell area, but also significantly achieve higher throughput for cell edge users.