Management of joint radio resources in heterogeneous networks Beyond 3G

Abstract

Heterogeneous Wireless Networks (HWNs) is a term referring to mixed networks made of different Radio Access Technologies (RATs) which aims to achieve the Always Best Connected concept (ABC). Users with multi-mode terminals can connect to di erent radio access technologies such as 802.16, 802.11, HSPA and LTE at the same time. The challenge consists of the choice of the suitable access network from the available RATs list; the decision process is called the Network Selection (NS). The network selection process depends on several parameters such as QoS, mobility, cost, energy battery etc. Several methods and approaches have been proposed to address this issue. Two main contributions are presented in this thesis, the rst one called modi ed-SAW function to deal with the drawbacks of the legacy SAW, the proposed solution outperforms almost all the famous Multi Attribute Decision Making methods and eliminates the problem of rank reversal. The second contribution consists of presenting a framework that allows the users to select the best networks for the whole call session, especially from a mobility perspective. The framework consists of several steps, starting by the path prediction which is done using the Markov model order 2. The second step is to make the network selection on the zones of each predicted path, while the third step is to get the good RAT con guration for each predicted path. We use another function to select one of the best con gurations to be used for all the possible used paths. The results show that our proposal performs very well by eliminating the unnecessary vertical handovers while maintaining a good Quality of Service (QoS).