Tools and Techniques for Heterogeneous Networks Coexistence

The world has become interconnected like never before, in diverse and complex ways and his diversity and complexity doesn’t seem to slow down. The increasing demand for higher network capacity and new applications and network presence is putting more pressure on even more growth and interconnection of existing network technologies and toward the research and development of new versatile network architectures that embrace heterogeneity and pervasiveness as an initial design paradigm. This surge in scale and complexity, plus the proliferation of heterogeneous wireless networks, challenges network researchers to come with novel techniques and methodologies that can achieve affordable, credible and reproducible results, for the development and experimentation with the various network architectures and communications protocols involved. It also brings complex challenges that reflect the complexity and diversity of the involved Wireless Networks technologies. For instance we show that LTE/WiFi coexistence problem associated with the current interest in providing unlicensed band access ability LTE networks , is an example of a problem where current research has been dealing with such challenges like Interference management, heterogeneous networks coexistence, and resource allocation. The work conducted as part of this dissertation is with the goal to tackle two main research problems. First, we set to develop a novel Simulation/Emulation framework for enabling large scale and flexible studies of Cognitive/Heterogeneous Wireless Networks and their related characteristics. This framework provides an environment for creative and flexible research experimentation using modern simulation technique. Second, we examined the problem of LTE/WiFi Coexistence as a current example of a complex Heterogeneous Wireless Networks Coexistence problem, and we proposed a novel algorithm that tackles this issue after a detailed review of the proposed solutions and understating of both systems behavior in a coexistence environment. This work was accompanied with a testbed built to allow real validation of coexistence mechanisms, combined with accurate simulation tools that provide relative accuracy from Physical Layer up to the Network Layer.