  -The focus of this paper is targeted towards multi-cell 5G networks which are
composed of HPNs (High Power Node) such as evolved NodeBs (HPNs) that control
signaling and system broadcasting information and of simplified LPNs (Low Power
Node) co-existing in the same operating area and sharing the scare radio
resources. Consequently, greater emphasis is given to Inter-Cell Interference
Coordination (ICIC) based on multi-resource management techniques that take in
particular user association into account. Beside user association to HPNs, this
paper takes also power control and scheduling into consideration. This
addressed problem is remained largely unsolved, mainly due to its non-convex
nature that makes the global optimal solution difficult to obtain. We address
the user association challenge according to the two broadly adopted approaches
in wireless networks: the network-centric approach where user association is
allocated efficiently in a centralized fashion; and the user-centric approach
where distributed allocation prevails for reduced complexity. The scheduling
and HPNs power allocation are solved in a centralized fashion, in order to
reach an optimal solution of the joint optimization problem.
