Radio Access Techniques for Heterogeneous Wireless Networks (RACHEL)

Mobile communications market forecasts an exponential growth of mobile subscriptions and data traffic over the next few years. Such trend is driven by a new generation of wireless users equipment, the proliferation of data rate intensive applications and machines willing to communicate over the mobile networks. Conventional approaches to design cellular networks such as increasing the number of macrocell sites, or enhancing the macrocell radio access features, are widely believed to be insufficient to avoid the foreseeable collapse of currently deployed mobile networks. In this project, a different approach is followed: complementing the conventional macrocell network with small cells (micro-, pico- and femtocells) equipped with lower power nodes and Machine-to-Machine (M2M) communications, thereby creating an Heterogeneous wireless Network (HetNet). Such approach is considered as the most promising way to increase the capacity and data rate of mobile wireless networks. Although an effective solution, HetNets still have a large number of technical challenges unsolved, the most important being the mitigation and coordination of the interferences between macro and small cells. RACHEL is expected to lead to significant progress beyond the current state-of-the-art in a number of radio access techniques for HetNets.