Energy efficient resource allocation in two-tier heterogeneous network with inband full-duplex communications

In this paper we investigate energy-efficient resource allocation in a two-tier orthogonal frequency division multiple access (OFDMA) network with inband full-duplex communications. The base station (BS) assignment, subcarrier and power allocation policies are jointly considered to optimize system's energy efficiency (EE) and to satisfy users' quality of service (QoS) in both uplink and downlink. We formulate the energy efficient resource allocation as a mixed integer and non-convex optimization problem which is generally hard to solve. To deal with this complexity, we first propose two heuristic algorithms for BS assignment and subcarrier allocation, then we transform the main power allocation problem into an equivalent convex one, and address it by Lagrangian dual decomposition method. Simulation results show that our proposed algorithm can considerably increase system's EE as compared to the existing works.