Joint Access Selection and Heterogeneous Resources Allocation in UDNs with MEC Based on Non-Orthogonal Multiple Access

Abstract

The increasing requirements for high data rate and powerful computing have posed new challenges to the wireless networks. Ultra-dense networks (UDNs) and mobile edge computing (MEC) are proposed to combine together as an inspiring solution. In this paper, we investigate the problem of joint access selection (AS) and resource allocation (RA) in UDNs with MEC based on non-orthogonal multiple access (NOMA). Multiple access points (APs) are organized to provide required services for a user equipment (UE). We design a utility function by quantifying the heterogeneous resources of APs and UEs, and then propose an AS algorithm. Proper APs responsible for communication and computation are selected for the UE respectively according to its multiple requirements. Then, to maximize the system energy efficiency (EE), the heterogeneous RA problem is formulated as a mixed-integer non-linear programming (MINP) problem. For ease to resolve, we divide the original problem into two subproblems: subcarriers allocation and power allocation. The quantum behaved particle swarm optimization (QPSO) algorithm is also introduced to derive the solution with low complexity. Finally, the simulation results demonstrate that the proposed scheme has good performance in energy efficiency under UEs requirements.