Optimizing Power by Combining Small Cells with a Massive MIMO for Maximum Energy Efficiency Under Two Path Loss Models

Currently, we are proceeding towards the 5thgeneration of wireless networks. The 5G is expected to utilize very wide bandwidth and would have the greater capacity compared to 4G. Therefore, the energy efficiency is one of the prominent roles in the design criterion. To achieve the maximum energy efficiency, the typical approaches are to increase the throughput or to decrease the power consumption. Recently, the approach to combine the small cell access points to Massive MIMO has been proved as one efficient way to achieve the maximum energy efficiency. In this work, the approach to combine two type of network, namely Small Cell Access Point (SCA) and Base Station (BS) with Massive MIMO, is considered for designing an energy efficient system. We investigate further this approach by extending the simulation to cover both 3GPP LTE as well as IMT 2020 environment with two different carrier frequencies under three scenarios. The performance is measured and compared with the existing work in terms of total power consumption per subcarrier of both the Base Station (BS) and Small Cell Access Points (SCAs). It is apparent that our proposed method provides the higher information rate at the same total power per sub carrier than the existing work. Additionally, general speaking, the 3GPP path loss model provides the lower total power consumption per sub carrier at BS than IMT-2020, while both path loss models almost has no impact on total power consumption at SCAs, regardless of carrier frequency and the number of antennas adopted in Massive MIMO at BS.