The surge of mobile data traffic places strain on 3G/4G cellular networks. At high traffic density areas offloading to Wi-Fi costs less than the expansion of the marco network. However the addition of another (moreover non-3GPP) access technology raises interworking issues. One of them is the selection mechanism of the most suitable access technology and access network by the UE. This demo investigates the feasibility of a system where a network entity activates/deactivates cells and selects the point of access for each UE. The objective is to save power by turning off dispensable network elements while also considering QoS requirements.

This article investigates the problem of the allocation of modulation and coding, subcarriers and power to users in LTE. The proposed model achieves inter-cell interference mitigation through the dynamic and distributed self-organization of cells. Therefore, there is no need for any a prior frequency planning. Moreover, a two-level decomposition method able to find near optimal solutions is proposed to solve the optimization problem. Finally, simulation results show that compared to classic reuse schemes the proposed approach is able to pack more users into the same bandwidth, decreasing the probability of user outage.

This work presents a novel approach for the avoidance of cross-tier interference in two-tier networks comprised of Orthogonal Frequency Division Multiple Access (OFDMA) macrocells and femtocells. This new technique is based on the use of Intracell HandOvers (IHOs), and it makes possible that either a macrocell or a femtocell can reassign its sub-channel or power allocation upon the detection of cross-tier interference. Simulation results show that this approach is able to cope with the cross-tier interference issues intrinsic to closed access femtocells, and the increased number of HandOvers (HOs) resulting from open access femtocells.

This work presents 2 novel approaches for the self-organization of Orthogonal Frequency Division Multiple Access (OFDMA) femtocells, in which the femtocell is able to dynamically sense the air interface and tune its sub-channel allocation in order to reduce inter-cell interference and enhance system capacity. In the sensing phase, these techniques make use of either messages broadcast by the femtocells or measurements reported by the users, while in the tuning phase, they provide a good solution for the frequency assignment problem. Results shows that it is recommend to use information collected at the user position (measurement reports), when devising self-organization algorithms for tuning the parameters of femtocells.

In this paper we propose a new traffic engineering scheme to be used jointly with protection in multi-layer, grooming-capable, optical-beared networks. To make the working and protection paths of demands better adapt to changing traffic and network conditions we propose the adaptive multi-layer traffic engineering (AMLTE) scheme that "tailors" i.e., fragments and de-fragments wavelength paths in a fully automatic distributed way.