Coverage-based cooperative radio resource allocation in mobile communication systems

Abstract

This thesis focuses on applying adaptive system level cooperative coverage to wireless communication networks and proposes an Adaptive Coverage System (ACS) for flexible and resilient radio coverage to handle time-varying geographic traffic distribution, providing better than conventional radio resource allocation results. The ACS utilises antenna arrays called Semi-Smart Antennas to shape cell coverage to alleviate cell overloading and balance loads as equally as possible among cells. Previously work in this field used a Bubble Oscillation Algorithm (BOA) to solve the load balancing problem in the ACS. Modification is made to the core algorithm to enhance its performance for its applications in WCDMA networks, to handle the impact of complex radio propagation environment. The work presented in this thesis then extends into tackling the problem from an optimisation problem point of view. It firstly examines the dynamics of user assignment in a network level and based on these findings, the possibility and approaches towards finding optimal coverage shapes for a mobile network are then presented, including problem formulation, algorithm design, and simulation results. This thesis investigates a system wide cooperative coverage approach to explore the potentials of adaptive coverage systems, has achieved sub-optimal radio resource allocation results, and provides an insight into general network-level radio resource allocation problems and their solutions.