we address the optimization problem of maximizing uplink energy efficiency, defined as sum of users bits-per-joule (bpj), in a multi-cell multi-user OFDMA network. Firstly, we propose a non-cooperative distributed scheme, in which mobile stations (MS) in different cells with given subcarrier assignment (SA) adjust the modulation and transmit power non-cooperatively, to optimize its own bpj. An advanced non-cooperative BS-controlled resource allocation scheme, in which the base station in each cell jointly performs SA, modulation adaptation, and power control for MSs in a non-cooperative manner, is proposed. Numerical results illustrate the tradeoff between energy and spectral efficiency, and show the proposed scheme makes great improvement on bpj with marginal loss of throughput as compared to other conventional scheme.
- energy efficiency
- Resource allocation