The standard 3G/UMTS has launched the first multimedia applications for mobile phones and tablets. The new standard 4G/LTE (Long Term Evolution) has mobile broadband objective. In this standard a huge effort has been done on automatic network reconfiguration based on customer demand variation in a process called Self-Organizing Network (SON). The work of this thesis lies in this direction. Reconfiguration of networks lies mainly in the direction of models, methods and tools to analyze network Key Performance Indicators and automatically configure its settings. We mainly worked on the air interface parameters such that frequency assignment, emitted power and pattern vertical inclination.In this context, given the high variability of optimization input data issued from the network, this thesis focuses on robust optimization under constraints. The robust optimization refers to a set of processes to provide solutions to combinatorial problems with uncertain and variable scenarios of data over time. The first Section presents the principles of Self-Organizing Network (SON). The second Section concerns the state of the art on robust optimization. The third Section defines the mathematical model to optimize for which traffic data (distribution of customers and throughput requirements on the service area) take variable values over time. A data diagnostic phase on the network operation and a sensitivity analysis of the solutions were made in the fourth Section with several local search algorithms. The fifth Section presents the work of design, development and test of a Tabu Search method and a thorough analysis of SON control methodology proposed for 4G.
Models and algorithms for robust optimization in self-Organizing Networks (SON) of 4G mobile networks (LTE)