  Interference coordination between high-power macros and low-power picos
deeply impacts the performance of heterogeneous networks (HetNets). It should
deal with three challenges: user association with macros and picos, the amount
of almost blank subframe (ABS) that macros should reserve for picos, and
resource block (RB) allocation strategy in each eNB. We formulate the three
issues jointly for sum weighted logarithmic utility maximization while
maintaining proportional fairness of users. A class of distributed algorithms
are developed to solve the joint optimization problem. Our framework can be
deployed for enhanced inter-cell interference coordination (eICIC) in existing
LTE-A protocols. Extensive evaluation are performed to verify the effectiveness
of our algorithms.
