Cooperative self-organized optimal power control for interference mitigation in femtocell networks

The deployment of the latest third generation wireless networks along with the explosive growth of advanced mobile devices demands additional electromagnetic spectrum to support both a growing number of users and new bandwidth intensive applications. Self-organizing features that facilitate deployment, operation and management of femtocells are common requirements of modern standards. Femtocells are designed to be installed by the user in unplanned locations thus it is critical to mitigate the interference created for macrocells as well as that between femtocells. In our research we look at the power control for interference management in femtocell networks using cooperative optimal control theory. We propose a cost index and a quadratic programming framework that takes into consideration path losses between femtocells and enables a solution that arrives to an optimal transmission power in the downlink. Our framework enables femtocell transmitters to set operation points that yield signal quality guarantees for indoor users while managing the interference between femtocells.