A successive coordinated power allocation water-filling algorithm for heterogeneous OFDMA cellular systems

This paper proposes a successive coordinated power allocation (SCPA) scheme for orthogonal frequency division multiple access (OFDMA) systems based on the water-filling algorithm. The model assumes two transmitters belonging to heterogeneous cells, i.e. a macro cell and a micro/pico cell with predefined different power capabilities that cover a common geographical area over a channel that includes path loss and shadowing. The main idea is the reduction of the computation complexity and the minimization of information exchange between the two transmitters while preserving similar performance with the optimal cooperative power allocation (OCPA) joint transmission algorithm, recently proposed in the literature. The algorithms are evaluated via extensive Monte-Carlo simulations. The results show that the proposed algorithm provides similar sum rate than OCPA and presents a higher mean number of serving mobile units while reducing, at the same time, the complexity by roughly to orders of magnitude.