Energy-aware competitive link adaptation in small-cell networks

This work proposes a distributed power allocation scheme for maximizing the energy efficiency in the uplink of non-cooperative small-cell networks based on orthogonal frequency-division multiple-access technology. This is achieved by modeling user terminals as rational agents that engage in a non-cooperative game in which every terminal selects the power loading so as to maximize its own utility (the user´s throughput per Watt of transmit power) while satisfying minimum rate constraints. In this framework, we prove the existence of a Debreu equilibrium (also known as generalized Nash equilibrium) and we characterize the structure of the corresponding power allocation profile using techniques drawn from fractional programming. To attain the equilibrium in a distributed fashion, we also propose a method based on an iterative water-filling best response process. Numerical simulations are then used to assess the convergence of the proposed algorithm and the performance of its end-state as a function of the system parameters.