Inter-cell Coordinated Transmission Power Control for IDMA-Based Random Access

Abstract

This paper proposes an inter-cell coordinated transmission power control (TPC) scheme for interleave division multiple access (IDMA)-based random access that supports massive machine-type communications (mMTC) in the fifth generation mobile communication system. In IDMA-based random access, attempts to detect separately multiple packets are made using a successive interference canceller (SIC) at the base station receiver to achieve multi-packet reception. Therefore, the TPC in IDMA-based random access should achieve uniform transmission quality within a cell to actualize mMTC, while taking into account its impact on the signal separation capability during the SIC process and inter-cell interference levels. The proposed scheme is a frequency block-dependent fractional TPC where the overall random access bandwidth is divided into two frequency blocks each of which is allocated to either cell-inner terminals or cell-edge terminals. By coordinating the frequency block usage between neighboring cells, the proposed TPC achieves inter-cell interference statics appropriate for attaining uniform transmission quality within a cell, while the frequency block-dependent fractional TPC achieves appropriate received power distribution among terminals from the viewpoint of the SIC process. Computer simulation results show in quantitative terms the effectiveness of the proposed scheme.