Performance Analysis of Small Cell and Distributed Antenna Systems for Indoor Mobile Communications

Fifth generation (5G) mobile communication systems aim to provide high data rate wireless transmissions and ubiquitous coverage to users but achieving this objective remains a challenge particularly in regions with high user density, such as urban/metropolitan areas and within buildings. To support users in indoor environments, indoor wireless communication systems are required, but frequency spectrum allocations are limited and requires reuse of the limited spectrum. Frequency reuse causes co-channel interference, which is detrimental to the performance and capacity of
indoor systems. In order to design efficient and reliable indoor systems, a thorough understanding of co-channel interference within buildings is vital. This paper presents a comparative study of the performance of indoor deployed small cell base station (SBS) and indoor distributed antenna systems (DAS) in an isolated multi-storey building. Each floor of the building is equipped with either an indoor SBS or an indoor DAS where geographically distributed remote radio heads (RRHs) are connected to a central unit (CU), and frequency reuse
is employed among floors. Signal propagation characteristics within multi-storey buildings and the impact of inter floor interference on system performance is analysed and compared for both systems. The effect of different reuse distances, pathloss exponents, penetration loss and co-channel interference on achievable rate is analysed over a wide range of potential mobile equipment (ME) locations.