Cooperation and migration for future communication networks

Abstract

5G networks will have to address challenges, related to capacity, data rate, latency, connectivity, costs and Quality of Experience (QoE), that LTE-A Long Term Evolution-Advanced) is not able to properly deal with. For this reason, research community is working to identify the set of key technologies that will enable the future mobile network. Three of these technologies fall in the areas of cooperative approaches for wireless networks, Software Defined Networking (SDN), and Network Function Virtualization (NFV). In this thesis work, some original results concerning the aforementioned technologies will be presented, by reserving a greater emphasis to the first one. Specifically, at first, the performance analysis of Multiple-Input Multiple-Output (MIMO) cooperative multiple-relay systems corrupted by Gaussian noise, in the case of naive (non-optimized) approach for the processing at the source and relay nodes, will be presented. Then, the optimal processing design will be faced based on the minimization of the arithmetic mean, over all the substreams, of the symbol error probabilities. At this point, the design of a new equalizer for a Single-Input Single-Output (SISO) Orthogonal-Frequency Division Multiplexing (OFDM) system affected by impulsive noise will be presented and the impact of the joint employment of cooperation and space-time block coding will be shown. At the end, with reference to the migration network primitive, a simplified mathematical model, that unveils the dependence of the total migration time and downtime of the virtual machine memory transfer on the main WAN parameters (such as capacity, buffering, and propagation delay) will be developed