Self-Organizing Network (SON) technology aims at autonomously deploying,
optimizing and repairing the Radio Access Networks (RAN). SON algorithms
typically use Key Performance Indicators (KPIs) from the RAN. It is shown that
in certain cases, it is essential to take into account the impact of the
backhaul state in the design of the SON algorithm. We revisit the Base Station
(BS) load definition taking into account the backhaul state. We provide an
analytical formula for the load along with a simple estimator for both elastic
and guaranteed bit-rate (GBR) traffic. We incorporate the proposed load
estimator in a self-optimized load balancing algorithm. Simulation results for
a backhaul constrained heterogeneous network illustrate how the correct load
definition can guarantee a proper operation of the SON algorithm.Comment: Wireless Communications Letters, IEEE, 201