Resource allocation optimization for hybrid access mode in heterogeneous networks

The dynamic optimization problem for radio resource allocation in two-tier heterogeneous networks (HetNets) under the hybrid access mode is researched in this paper. To make the average utility of user throughput arbitrarily close to the optimum and maintain system queue stability under instantaneous and average power constraints, radio resource allocation optimization problem is formulated, and the corresponding solution that takes admission control, cell association, congestion control, subchannel and power allocation into account altogether is proposed, which is based on the Lyapunov optimization framework. The solution decomposes the optimization problem into three subproblems, in which the first two are linear and the third is mixed-integer non-linear. Both analysis and simulation results have verified that the proposal can achieve a significant utility performance gain under maintaining the queue stability with an [O(V), O(1/V)] tradeoff between throughput-utility optimality and traffic queue congestion.