Joint frequency/power update algorithms for self-organizingfemtocell networks

Heterogenous networks are resorted as one of the most promising ways for meeting the rapidly increasing data demand. As the smallest members of heterogenous networks, femto base stations also carry a huge potential for increasing the service quality in indoor areas. However, their unplanned deployment by the end users increases the possibility of having dense femtocell networks with unknown topologies. Therefore, self–organizing methods have great importance in resource allocation of femtocell networks. In this thesis, power and frequency allocation problems are studied for OFDMA femtocell networks. First, we present a power update algorithm for the general wireless networks as an alternative for a well known power control algorithm from the literature. Then, this algorithm and another power control algorithm from the literature are extended for the OFDMA femtocell networks. As opposed to the previous versions, which are applicable only in networks where each base station can have at most one user, the extended algorithms can be used by base stations that have more than one user. Additionally, a frequency allocation scheme is developed in order to increase the maximum achievable SINR in femtocell networks. Furthermore, by merging this scheme with the proposed power update algorithms, we present two joint frequency/power update algorithms with increased performance. Convergence and optimality analyses of all the proposed algorithms are carried out and illustrated with numerical results.