Energy-aware user association in heterogeneous networks with renewable energy supplies

Abstract

To alleviate the burden on power grid in heterogeneous cellular networks, energy harvesting (EH) has inspired thorough research in both academia and industry. However, the mismatched distribution of energy storage and traffic load leads to a bad result that the renewable energy can not be utilized sufficiently. To tackle this issue, we propose an energy-biased-received-power (EBRP) scheme (i.e., users incline to associate with BSs at higher energy level) for energy-load balancing and on-grid energy saving. Taking into account the dynamic EH behavior, a performance analysis of coverage probability and energy efficiency is conducted in a two-tier heterogeneous network with EH enabled personal cells. Numerical and simulation results are provided along with the maximum-biased-received-power (MBRP) scheme. Numerical results show that the reduction of maximum transmit power at base stations is favorable for enhancing energy efficiency. Moreover, it is revealed that the proposed scheme shows superiority in energy-load balancing when the energy efficiency is comparable with that of the MBRP scheme.