Joint Spectral Efficiency and Power Allocation Optimization in IEEE 802.16m

With today´s limited bandwidth, high data rate services, and energy efficiency requirements, maximizing the spectral efficiency and minimizing the consumed power becomes essential. Investigating the issues impeding spectral efficiency maximization and consumed power minimization for mobile systems is crucial for solving this contemporary problem. This paper aims to optimize the utilization of the scarce mobile spectrum and the amount of power consumption in the multi-cell IEEE 802.16m networks. A return on investment model adopting a utility optimization technique is proposed; the model objective is to increase the revenue of the mobile service providers by maximizing the normalized spectral efficiency and decrease the operational cost by minimizing the power consumed in the network. Based on this model, we propose two phases scheme (distributed and centralized) to solve the joint spectral and power optimization problem. The problem is solved to identify the optimal distributed resources assignment and the central down-link frequency partition configuration that achieves the model objective. Simulation results show that the optimal solution significantly improves the system power consumption while maintaining the normalized spectral efficiency, yet with high computational complexity. Accordingly, an effective suboptimal solution utilizing a polynomial-time heuristic is proposed for practical implementations.