1 research outputs found
Distributed Cluster Formation and Power-Bandwidth Allocation for Imperfect NOMA in DL-HetNets
In this paper, we consider an non-ideal successive interference cancellation
(SIC) receiver based imperfect non-orthogonal multiple access (NOMA) schemes
whose performance is limited by three factors: 1) Power disparity \&
sensitivity constraints (PDSCs), 2) Intra-cluster interference (ICRI), and 3)
Intercell-interference (ICI). By quantifying the residual interference with a
fractional error factor (FEF), we show that NOMA cannot always perform better
than orthogonal multiple access (OMA) especially under certain receiver
sensitivity and FEF levels. Assuming the existence of an offline/online ICI
management scheme, the proposed solution accounts for the ICI which is shown to
deteriorate the NOMA performance particularly when it becomes significant
compared to the ICRI. Then, a distributed cluster formation (CF) and
power-bandwidth allocation (PBA) approach are proposed for downlink (DL)
heterogeneous networks (HetNets) operating on the imperfect NOMA. We develop a
hierarchically distributed solution methodology where BSs independently form
clusters and distributively determine the power-bandwidth allowance of each
cluster. A generic CF scheme is obtained by creating a multi-partite graph
(MPG) via partitioning user equipments (UEs) with respect to their channel
gains since NOMA performance is primarily determined by the channel gain
disparity of cluster members. A sequential weighted bi-partite matching method
is proposed for solving the resulted weighted multi-partite matching problem.
Thereafter, we present a hierarchically distributed PBA approach which consists
of the primary master, secondary masters, and slave problems...Comment: To appear in IEEE TCO